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1
Clough, Tim J. "Fate of urine nitrogen applied to peat and mineral soils from grazed pastures." Lincoln University, 1994. http://hdl.handle.net/10182/1030.
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This study has provided fundamental information on the fate of urine nitrogen (N) when applied to pasture soils. In this work the three pasture soils used were a Bruntwood silt loam (BW), an old well-developed (lime and fertilizer incorporated and farmed for more than 20 years) peat soil (OP) and a young peat (YP) which was less developed (farmed for about 10 years). Initial soil chemical and physical measurements revealed that the peat soils were acidic, had higher cation exchange capacities, had greater carbon:nitrogen ratios and were better buffered against changes in soil pH than the BW soil. However, the BW soil was more fertile with a higher pH. The peat soils had lower bulk densities and higher porosities. Four experiments were performed. In the first experiment ¹⁵N-labelled urine was applied at 500 kg N ha⁻¹ to intact soil cores of the three soils. Treatments imposed were the presence and absence of a water table at two temperatures, 8°C or 23° C, over 11-14 weeks. ¹⁵N budgets were determined. This first experiment showed that the nitrification rate was faster in the BW soil and was retarded with a water table present. Significant leaching of nitrate occurred at 8°C in the BW soil without a water table. This was reduced when a water table was present. Leaching losses of urine-N were lower in the peat soils than in the BW soil. Apparent denitrification losses (i.e. calculated on a total-N recovery basis) ranged from 18 to 48 % of the ¹⁵N-applied with the greatest losses occurring in the peat soils. The second experiment examined denitrification losses, over 30 days, following the application of synthetic urine-N at 420 kg N ha⁻¹ to small soil cores situated in growth cabinets. The effects of temperature (8°C or 18°C) and synthetic urine (presence or absence) were measured on the BW and OP soils. Nitrous oxide (N₂0) measurements were taken from all soil cores and a sub-set of soil cores, at 18°C, had ¹⁵N-labelled synthetic urine-N applied so that ¹⁵N-labelled nitrogen gases could be monitored. This experiment showed that the application of synthetic urine and increased soil temperature enhanced denitrification losses from both soils. Denitrification losses, at 18°C, as ¹⁵N-labelled nitrogen gases accounted for 24 to 39 % of the nitrogen applied. Nitrous oxide comprised less than half of this denitrification loss. Losses of N₂0 in leachate samples from the soil cores accounted for less than 0.1 % of the nitrogen applied. A third experiment, using Iysimeters, was performed over a 150 day period in the field. The six treatments consisted of the 3 soils with applied synthetic urine, with or without a simulated water table; each replicated three times. Lysimeters were installed in the field at ground level and ¹⁵N-labelled synthetic urine-N was applied (500 kg N ha⁻¹) on June 4 1992 (day 1). Nitrification rates differed between the soils following the trend noticed in the first experiment. As in the first experiment, nitrate was only detected in the leachate from the BW soil and the inclusion of a water table reduced the concentration of nitrate. In the BW soil, the leachate nitrate concentrations exceeded the World Health Organisation's recommended limit (< 10 mg N L-1) regardless of water table treatment. No nitrate was detected in the leachates from the peat soils but there was some leaching of organic-N (< 5 % of N added) in all the peat soil treatments. Denitrification losses were monitored for the first 100 days of the experiment. In the BW soil without a water table, N₂0 production peaked at approximately day 20 and accounted for 3 % of the nitrogen applied. In the peat soils the measured denitrification losses accounted for less than 1 % of the nitrogen applied. Apparent denitrification losses in the peats were, however, calculated to be approximately 50 % of the ¹⁵N-labelled synthetic urine-N applied. It is postulated that the difference between apparent denitrification losses and those measured could have been due to; loss of dinitrogen in leachate, protracted production of dinitrogen below detectable limits, production of denitrification gases after measurements ceased (i.e. days 100 to 150) and entrapment of dinitrogen in soil cores. Due to the apparent denitrification losses being so high, further research into this nitrogen loss pathway was performed. The fourth and final experiment measured denitrification directly using highly enriched (50 atom %) ¹⁵N-labelled synthetic urine-N. It was performed in a growth cabinet held initially at 8°C. The ¹⁵N-labelled synthetic urine was applied at 500 kg N ha⁻¹ to small soil cores of each soil type. Fluxes of N₂0 and ¹⁵N-labelled gases were measured daily for 59 days. On day 42 the temperature of the growth cabinet was increased to 12°C in an attempt to simulate the mean soil temperature at the end of the field experiment. Up to this time, production of nitrogenous gases from the YP soil had been very low. Interpretation of gaseous nitrogen loss in the YP soil was difficult due to the possibility of chemodenitrification occurring. However, in the OP and BW soils, gaseous losses of nitrogen (determined as ¹⁵N-labelled gas) represented 16 and 7 % of the nitrogen applied respectively. Nitrous oxide comprised approximately half of this gaseous nitrogen loss, in both the OP and BW soils. This work implies that urine-N applied to the mineral soil (BW) could potentially threaten the quality of ground water due to nitrate contamination through leaching. In contrast, denitrification appears to be the major loss mechanism from the peat soils, with the production of nitrous oxide being the primary focus for any environmental concern. Future work should examine the fate of the nitrate leached from the BW soil and the potential for dilution, plant uptake or denitrification below a 30 cm soil depth. A better understanding of the denitrification mechanisms could help reduce denitrification and thereby improve the efficiency of nitrogen use and reduce the output of nitrous oxide.
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Ford, Colleen D. "The fate of nitrogen in lactose-depleted dairy factory effluent irrigated onto land." Lincoln University, 2008. http://hdl.handle.net/10182/837.
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A two-year lysimeter study was undertaken to compare the environmental effects (e.g. nitrate leaching and nitrous oxide emissions) of soil applied lactose-depleted dairy factory effluent (LD-DFE) with lactose-rich DFE. The aim of this experiment was to determine the fate of nitrogen from LD-DFE and dairy cow urine applied to a Templeton fine sandy loam soil (Udic Ustrochrept), supporting a herbage cover of ryegrass (Lolium perenne) and white clover (Trifolium repens). Measurements were carried out on the amount of nitrogen lost from the soil via leaching, lost by denitrification, removed by the pasture plants, and immobilized within the soil organic fraction. Further, a comparison between the fate of nitrogen in LD-DFE irrigated onto land under a "cut and carry" system, as opposed to a "grazed" pasture system was undertaken. Lactose-depleted dairy factory effluent was applied at three-weekly intervals during the summer months at rates of 25 and 50 mm, until nitrogen loading targets of 300 and 600 kg N ha⁻¹ yr⁻¹ had been achieved. Measured leaching losses of nitrogen averaged 2 and 7 kg N ha⁻¹ yr⁻¹ for Control 25 and Control 50 treatments; 21, 20 and 58 kg N ha⁻¹ yr⁻¹ for 25 and 50 mm "cut and carry" treatments respectively; and 96 kg N ha⁻¹ yr⁻¹ for the 25 mm "grazed" treatment. The range of nitrate-N leaching loss from LD-DFE plus urine is no different from the lactose-rich DFE nitrate leaching loss. Uptake of nitrogen by the growing pasture averaged 153, 184,340,352,483, and 415 kg N ha⁻¹ yr⁻¹ for Control 25, Control 50, LD-DFE 25 and LD-DFE 50 mm "cut and carry" treatments, and the LD-DFE 25 mm "grazed" treatment, respectively. Denitrification losses were 0.06, 4.4, 1.69, 19.70, and 7.4 kg N ha⁻¹ yr⁻¹ for Control 25, the LD-DFE 25 "cut and carry" treatments, the LD-DFE 25 mm "grazed" treatment, and calculated "paddock losses", respectively. Isotopic nitrogen studies found that 29.4 and 25.8% of applied LD-DFE nitrogen was immobilised in the LD-DFE 25 and LD-DFE 50 "cut and carry" treatments. The results of this experiment confirm the findings of the previous lactose-rich DFE study, in that the effects of grazing stock are of greater environmental concern than the removal of lactose from the effluent waste stream.
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Condron, Leo M. "Chemical nature and plant availability of phosphorus present in soils under long-term fertilised irrigated pastures in Canterbury, New Zealand." Lincoln College, University of Canterbury, 1986. http://hdl.handle.net/10182/1875.
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Soil P fractionation was used to examine changes in soil inorganic and organic P under grazed irrigated pasture in a long-term field trial at Winchmore in Mid-Canterbury. The soil P fractionation scheme used involved sequential extractions of soil with O.5M NaHCO₃ @ pH 8.5 (NaHCO₃ P), 0.1M NaOH (NaOH I P), 1M HCl (HCl P) and 0.1M NaOH (NaOH II P). The Winchmore trial comprised 5 treatments: control (no P since 1952), 376R (376 kg superphosphate ha⁻¹ yr⁻¹ 1952-1957, none since), 564R (564 kg superphosphate ha⁻¹ yr⁻¹ 1952-1957, none since) 188PA (188 kg superphosphate ha⁻¹ yr⁻¹ since 1952) and 376PA (376 kg superphosphate ha⁻¹ yr⁻¹ since 1952: Topsoil (0-7.5cm) samples taken from the different treatments in 1958, 1961, 1965, 1968, 1971, 1974 and 1977 were used in this study. Changes in soil P with time showed that significant increases in soil inorganic P occurred in the annually fertilised treatments (l88PA, 376PA). As expected, the overall increase in total soil inorganic P between 1958 and 1977 was greater in the 376PA treatment (159 µg P g⁻¹) than that in the 188PA treatment (37 µg P g⁻¹). However, the chemical forms of inorganic P which accumulated in the annually fertilised treatments changed with time. Between 1958 and 1971 most of the increases in soil inorganic P in these treatments occurred in the NaHCO₃ and NaOH I P fractions. On the other hand, increases in soil inorganic P in the annually fertilised treatments between 1971 and 1977 were found mainly in the HCl and NaOH II P fractions. These changes in soil P forms were attributed to the combined effects of lime addition in 1972 and increased amounts of sparingly soluble apatite P and iron-aluminium P in the single superphosphate applied during the 1970's. In the residual fertiliser treatments (376R, 564R) significant decreases in all of the soil inorganic P fractions (i.e. NaHCO₃ P, NaOH I P, HCl P, NaOH II p) occurred between 1958 and 1977 following the cessation of P fertiliser inputs in 1957. This was attributed to continued plant uptake of P accumulated in the soil from earlier P fertiliser additions. However, levels of inorganic P in the different soil P fractions in the residual fertiliser treatments did not decline to those in the control which indicated that some of the inorganic P accumulated in the soil from P fertiliser applied between 1952 and 1957 was present in very stable forms. In all treatments, significant increases in soil organic P occurred between 1958 and 1971. The overall increases in total soil organic P were greater in the annually fertilised treatments (70-86 µg P g⁻¹) than those in the residual fertiliser (55-64 µg P g⁻¹) and control (34 µg P g⁻¹) treatments which reflected the respective levels of pasture production in the different treatments. These increases in soil organic P were attributed to the biological conversion of native and fertiliser inorganic P to organic P in the soil via plant, animal and microbial residues. The results also showed that annual rates of soil organic P accumulation between 1958 and 1971 decreased with time which indicated that steady-state conditions with regard to net 'organic P accumulation were being reached. In the residual fertiliser treatments, soil organic P continued to increase between 1958 and 1971 while levels of soil inorganic P and pasture production declined. This indicated that organic P which accumulated in soil from P fertiliser additions was more stable and less available to plants than inorganic forms of soil P. Between 1971 and 1974 small (10-38 µg P g⁻¹) but significant decreases in total soil organic P occurred in all treatments. This was attributed to increased mineralisation of soil organic P as a result of lime (4 t ha⁻¹) applied to the trial in 1972 and also to the observed cessation of further net soil organic P accumulation after 1971. Liming also appeared to affect the chemical nature of soil organic P as shown by the large decreases in NaOH I organic P(78-88 µg P g⁻¹) and concomitant smaller increases in NaOH II organic P (53-65 µg P g⁻¹) which occurred in all treatments between 1971 and 1974. The chemical nature of soil organic P in the Winchmore long-term trial was also investigated using 31p nuclear magnetic resonance (NMR) spectroscopy and gel filtration chromatography. This involved quantitative extraction of organic P from the soil by sequential extraction with 0.1M NaOH, 0.2M aqueous acetylacetone (pH 8.3) and 0.5M NaOH following which the extracts were concentrated by ultrafiltration. Soils (0-7.5cm) taken from the control and 376PA annually fertilised treatments in 1958, 1971 and 1983 were used in this study. 31p NMR analysis showed that most (88-94%) of the organic P in the Winchmore soils was present as orthophosphate monoester P while the remainder was found as orthophosphate diester and pyrophosphate P. Orthophosphate monoester P also made up almost all of the soil organic P which accumulated in the 376PA treatment between 1958 and 1971. This indicated that soil organic P in the 376PA and control treatments was very stable. The gel filtration studies using Sephadex G-100 showed that most (61-83%) of the soil organic P in the control and 376PA treatments was present in the low molecular weight forms (<100,000 MW), although the proportion of soil organic P in high molecular weight forms (>100,000 MW) increased from 17-19% in 1958 to 38-39% in 1983. The latter was attributed to the microbial humification of organic P and indicated a shift toward more complex and possibly more stable forms of organic P in the soil with time. Assuming that the difference in soil organic P between the control and 376PA soils sampled in 1971 and 1983 represented the organic P derived from P fertiliser additions, results showed that this soil organic P was evenly distributed between the high and low molecular weight fractions. An exhaustive pot trial was used to examine the relative availability to plants of different forms of soil inorganic and organic P in long-term fertilised pasture soils. This involved growing 3 successive crops of perennial ryegrass (Lolium perenne) in 3 Lismore silt loam (Udic Ustochrept) soils which had received different amounts of P fertiliser for many years. Two of the soils were taken from the annually fertilised treatments in the Winchmore long term trial (188PA, 376PA) and the third (Fairton) was taken from a pasture which had been irrigated with meatworks effluent for over 80 years (65 kg P ha⁻¹ yr⁻¹). Each soil was subjected to 3 treatments, namely control (no nutrients added), N100 and N200. The latter treatments involved adding complete nutrient solutions with different quantities of N at rates of 100kg N ha⁻¹ (N100) and 200kg N ha⁻¹ (N200) on an area basis. The soil P fractionation scheme used was the same as that used in the Winchmore long-term trial study (i.e. NaHCO₃ P, NaOH I P, HCl P, NaOH II p). Results obtained showed that the availability to plants of different extracted inorganic P fractions, as measured by decreases in P fractions before and after 3 successive crops, followed the order: NaHCO₃ P > NaOH I P > HCl P = NaOH II P. Overall decreases in the NaHCO₃ and NaOH I inorganic P fractions were 34% and 16% respectively, while corresponding decreases in the HCl and NaOH II inorganic P fractions were small «10%) and not significant. However, a significant decrease in HCl P (16%) was observed in one soil (Fairton-N200 treatment) which was attributed to the significant decrease in soil pH (from 6.2 to 5.1) which occurred after successive cropping. Successive cropping had little or no effect on the levels of P in the different soil organic P fractions. This indicated that net soil organic P mineralisation did not contribute significantly to plant P uptake over the short-term. A short-term field experiment was also conducted to examine the effects of different soil management practices on the availability of different forms of P to plants in the long-term fertilised pasture soils. The trial was sited on selected plots of the existing annually fertilised treatments in the Winchmore long-term trial (188PA, 376PA) and comprised 5 treatments: control, 2 rates of lime (2 and 4 t ha⁻¹ ) , urea fertiliser (400kg N ha⁻¹ ) and mechanical cultivation. The above ground herbage in the uncultivated treatments was harvested on 11 occasions over a 2 year period and at each harvest topsoil (0-7.5 cm) samples were taken from all of the treatments for P analysis. The soil P fractionation scheme used in this particular trial involved sequential extractions with 0.5M NaHCO₃ @ pH 8.5 (NaHCO₃ P), 0.1M NaOH (NaOH P), ultrasonification with 0.1M NaOH (sonicate-NaOH p) and 1M HCl (HCl P). In addition, amounts of microbial P in the soils were determined. The results showed that liming resulted in small (10-21 µg P g⁻¹) though significant decreases in the NaOH soil organic P fraction in the 188PA and 376PA plots. Levels of soil microbial P were also found to be greater in the limed treatments compared with those in the controls. These results indicated that liming increased the microbial mineralisation of soil organic P in the Winchmore soils. However, pasture dry matter yields and P uptake were not significantly affected. Although urea significantly increased dry matter yields and P uptake, it did not appear to significantly affect amounts of P in the different soil P fractions. Mechanical cultivation and the subsequent fallow period (18 months) resulted in significant increases in amounts of P in the NaHCO₃ and NaOH inorganic P fractions. This was attributed to P released from the microbial decomposition of plant residues, although the absence of plants significantly reduced levels of microbial P in the cultivated soils. Practical implications of the results obtained in the present study were presented and discussed.
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Jones, Samantha. "Deconstructing the degradation debate : a study of land degradation in the Uluguru Mountains, Tanzania." Thesis, University of East Anglia, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338943.
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Aburas, Murad Milad. "Assessment of Soil Erodibility in Relation to Soil Degradation and land Use in mediterranean Libya." Thesis, University of Newcastle Upon Tyne, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.506543.
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Mare, Boussa Tockville <1979>. "Physical land degradation and loss of soil fertility: soil structural stability and bio-physical indicators." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6638/.
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This study investigates the changes in soil fertility due to the different aggregate breakdown mechanisms and it analyses their relationships in different soil-plant systems, using physical aggregates behavior and organic matter (OM) changes as indicators.
Three case studies were investigated: i) an organic agricultural soil, where a combined method, aimed to couple aggregate stability to nutrients loss, were tested; ii) a soil biosequence, where OM chemical characterisation and fractionation of aggregates on the basis of their physical behaviour were coupled and iii) a soils sequence in different phytoclimatic conditions, where isotopic C signature of separated aggregates was analysed.
In agricultural soils the proposed combined method allows to identify that the severity of aggregate breakdown affected the quantity of nutrients lost more than nutrients availability, and that P, K and Mg were the most susceptible elements to water abrasion, while C and N were mainly susceptible to wetting.
In the studied Chestnut-Douglas fir biosequence, OM chemical properties affected the relative importance of OM direct and indirect mechanisms (i.e., organic and organic-metallic cements, respectively) involved in aggregate stability and nutrient losses: under Douglas fir, high presence of carboxylate groups enhanced OM-metal interactions and stabilised aggregates; whereas under Chestnut, OM directly acted and fresh, more C-rich OM was preserved. OM direct mechanism seemed to be more efficient in C preservation in aggregates.
The 13C natural abundance approach showed that, according to phytoclimatic conditions, stable macroaggregates can form both around partially decomposed OM and by organic-mineral interactions. In topsoils, aggregate resistance enhanced 13C-rich OM preservation, but in subsoils C preservation was due to other mechanisms, likely OM-mineral interactions.
The proposed combined approach seems to be useful in the understanding of C and nutrients fate relates to water stresses, and in future research it could provide new insights into the complexity of soil biophysical processes.
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Harvey, Martin Alan Peter Taylor. "4-chlorobenzoate permeation and degradation in Arthrobacter." Thesis, University of Greenwich, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282671.
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Pascual, GarciÌa de Azilu Unai. "Modelling labour supply and soil quality in shifting cultivation agriculture : a study from YucataÌn, Mexico." Thesis, University of York, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288198.
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Norman, Mark D. P. "Microbiological analysis of soil perturbations associated with opencast coal mining and their consequences for restoration." Thesis, University of East London, 1995. http://roar.uel.ac.uk/3606/.
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The work presented in this thesis was performed firstly to highlight the changes wrought in restored soil systems following the disruptive activities of opencast coal mining, and thereafter to identify, simulate and assess the effects of some typical perturbations associated with these activities. The microbial community was used as a focus for these investigations and the methods of soil adenosine 5'- triphosphate content analysis, dehydrogenase activity analysis and ergosterol content analysis were utilised alongside several other physical and chemical determinations. A field study of restored sites of various ages after cessation of opencast coal mining was undertaken which reinforced the utility of the microbial measurements. Experimentation was performed to investigate the effects of soil storage (at two depths), physical disturbance, compaction and the effects of the different combinations of these perturbations. Novel findings were obtained largely due to the paucity of research addressing the controlled manipulation and careful interpretation of these individual perturbations, and their effects when combined. The storage of soil was found to be the dominant factor influencing the status of the microbial communities upon restoration, and also influencing the development of these communities and the emergent plant biomass, post-restoration. This study found that soil, reinstated after opencast coal mining, becomes quickly dominated by fungi and, under grassland management, this domination then subsides over many years to a more bacterialcharacterised system. Differences were identified between the action of physical disturbance and compaction on stored and unstored soils. The deleterious effect of physical disturbance on unstored soil and the apparent ameliorative effect on soil affected by opencast operations can be interpreted through the change in soil architecture engendered by this treatment. The severe disturbances associated with opencast coal mining were found to affect the soil biota, primarily in terms of enduring environmental change. Thus the study of soil ecology was used as a sensitive indicator of recovery of disturbed land, and the changing energy flow through detrital food-webs was used as a model to follow this recovery process.
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Edwards, Rebecca Jane. "Land degradation and local management strategies in hillside agriculture : a Jamaican case study." Thesis, Royal Holloway, University of London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322071.
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Majara, Ntina. "Land degradation in Lesotho : a synoptic perspective." Thesis, Link to the online version, 2005. http://hdl.handle.net/10019/1645.
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Lemenih, Mulugeta. "Effects of land use changes on soil quality and native flora degradation and restoration in the highlands of Ethiopia : implications for sustainable land management /." Uppsala : Dept. of Forest Soils, Swedish Univ. of Agricultural Sciences, 2004. http://epsilon.slu.se/s306.pdf.
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Tichagwa, Cornelius Gibson. "Land degradation in Mhondoro (Zimbabwe) : an environmental assessment of communal land uses and resource management practice." Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/52911.
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Thesis (MA)--Stellenbosch University, 2002.ENGLISH ABSTRACT: When land loses its intrinsic qualities or suffers a decline in its capabilities it is said to be degraded. Land degradation manifests itself in various forms such as deforestation, soil erosion, land, air and water pollution. In the context of sustainable development land degradation has become one of the world's major concerns. Now, more than ever before, it has become urgent to carry out empirical studies on the nature and extent of land degradation and to come up with appropriate responses to the problem. In much of the developing world communal natural resource management practices are common. It is often assumed that communal exploitation of common property resources such as woodlands, pastures, water sources and wildlife inevitably leads to land degradation. This is due to the belief that humankind would seek to derive maximum benefit from common pool resources without incurring any costs towards the conservation of those resources. This study was an environmental assessment of the impacts of communal land-use systems and common property resources management practices in the Mhondoro communal lands of Zimbabwe. The area has been subject to human settlement for over a century and is regarded as a typical representation of a well-established communal land management system. Several methods were used to make the assessment. These included the following: a questionnaire survey; interviews with key informants; soil and vegetation traverses and field measurements; tree density counts in demarcated plots; calculation of the population density and livestock density for the study area; completion of an environmental evaluation matrix and a communal projects sustainability index checklist; and analysis of geo-referenced time-lapse aerial photography covering a fifteen year period (1982-1997). It was established that serious land degradation had occurred in Chief Mashayamombe's ward in Mhondoro. Degradation manifested itself in the form of soil erosion and stream sedimentation, woodland depletion, pasture degradation and wildlife habitat destruction. Communal land-use and natural resource management practices are only partially to blame for this state of affairs. The fragile nature of the sandy soils of the uplands, the sadie soils of the vlei areas, combined with the fairly high rainfall amounts (annual average 750mm) make the area prone to soil erosion. Rainfall intensity tends to be high in the area and when the rain falls on the poorly vegetated, and highly erodible soils erosion occurs. The land has become severely stressed due to over-utilisation; a population density of 93 people per km2 and livestock density of 110 cattle per km2 were recorded. The land available for communal settlement in the area has been limited in extent. Due to the general poverty of the communal farmers the replacement of nutrients into the cultivated soil has not kept pace with the deteriorating condition of the land. Contrary to popular misconceptions, communal area residents have shown concern for environmental conservation through fallowing their fields, gully reclamation efforts, grazing schemes, woodland preservation and tree growing practices. Remedial and/or mitigatory measures for the environmental recovery of the area could adopt some of these well-established practices and incorporate them in a whole-catchment management strategy. Key words Land degradation, environmental degradation, pollution, environmental assessment, common property resources, communal land uses, sustainable resources management, sustainability indicators, soil erodibility, soil erosivity
AFRIKAANSE OPSOMMING: Wanneer grond sy intrinsieke waarde verloor of 'n afname in sy vermoë toon, kan gesê word dat die grond gedegradeer is. Gronddegradasie manifesteer in verskeie vorme, soos ontbossing, gronderosie, grond, lug en water besoedeling. Gronddegradasie het binne die konteks van volhoubare ontwikkeling wêreldwyd van besondere belang geword. Nou, meer as ooit vantevore, is dit noodsaaklik om empiriese studies uit te voer aangaande die aard en omvang van gronddegradasie, en om vorendag te kom met toepaslike reaksies tot die probleem. Gemeenskaps natuurlike hulpbron bestuur praktyke is algemeen in die ontwikkelende wêreld. Daar word dikwels veronderstel dat uitbuiting van gemeenskaplike eiendoms hulpbronne deur die gemeenskap, soos woude, weivelde, waterbronne en wild, onvermeidelik lei na gronddegradasie. Hierdie aanname het ontwikkel as gevolg van die oortuiging dat die mensdom daarna sal streef om maksimum voordeel te trek uit gemeenskaplike hulpbronne, sonder om enige koste aan te gaan ten opsigte van die bewaring daarvan. Hierdie studie behels 'n omgewings evaluering van die impakte van gemeenskaps grondgebruik sisteme en gemeenskaplike eiendoms hulpbron bestuur praktyke in die Mhondoro gemeenskaplike grond van Zimbabwe. Die area word al vir meer as 'n eeu deur mense bewoon, en word beskou as 'n tipiese voorbeeld van 'n gevestigde gemeenskaps grondbestuur sisteem. Verskeie metodes is toegepas met die evaluering, en sluit in: 'n vraelys opname; onderhoude met sleutel segspersone; grond en plantegroei opnames en veldopnames; boom digtheidstelling in afgebakende persele; berekening van bevolkingsen veedigtheid vir die studiegebied; opstelling van 'n omgewing evaluerings matriks en 'n gemeenskap projek volhoubaarheids indeks kontroleerlys; en 'n analise van geo-referenced time-lapse lugfoto's wat strek oor 'n tydperk van 15 jaar (1982-1997). Daar is vasgestel dat ernstige gronddegradasie voorkom in Hoofman Mashayamombe se wyk in Mhondoro. Degradasie word gemanifesteer in die vorm van gronderosie en stroom sedimentasie, uitputting van woude, weiveld degradasie en die verwoesting van wild habitatte. Gemeenskaps grondgebruik en natuurlike hulpbron bestuurspraktyke is net gedeeltelik verantwoordelik vir die stand van sake. Gronderosie vind plaas ook as gevolg van die sensitiewe aard van die sanderige grond van die hoogland, die sodic grond van die vlei areas, in kombinasie met redelike hoë reënval (gemiddeld 750mm per jaar). Reënval intensiteit in die area is geneig om hoog te wees, en erosie vind plaas wanneer reën val op die hoogs erodeerbare grond wat met yl plantegroei bedek is. Die grond verkeer onder geweldige druk as gevolg van oorbenutting; 'n bevolkingsdigtheid van 93 mense per km2 en veedigtheid van 110beeste per km2 is aangeteken. Die grond beskikbaar vir vestiging van gemeenskappe word in omvang beperk. Die vervanging van grondvoedingstowwe in bewerkte grond hou nie tred met die agteruitgang in die kondisie van die grond nie, as gevolg van die algemene armoede van die gemeenskapsboere. Inwoners van die gemeenskapsarea , teenstrydig met algemene wanopvattings, toon besorgdheid ten opsigte van omgewingsbewaring deur die grond braak te lê, donga herwinnings pogings, wei velds planne, bewaring van woude en praktyke ten opsigte van die groei van bome. Remediërende en/of versagtende maatstawwe vir die herstel van die omgewing kan van hierdie gevestigde praktyke inkorporeer in 'n bestuursstrategie wat die hele opvangsgebied insluit. Sleutelwoorde Gronddegradasi e, omgewingsde gradasi e, besoedeling, omgewingsassessering, gemeenskaplike eiendoms hulpbronne, gemeenskaplike grondgebruik, volhoubare hulpbron bestuur, volhoubaarheids aanwysers, grond erodeerbaarheid, grond verwering.
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Emadodin, Iraj [Verfasser]. "Impacts of land management on soil formation and soil degradation during middle and late holocene in Schleswig-Holstein (Germany) / Iraj Emadodin." Kiel : Universitätsbibliothek Kiel, 2008. http://d-nb.info/1019809760/34.
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Abate, Solomon Wachs Theodore. "Land use dynamics, soil degradation and potential for sustainable use in Metu area, Illubabor region, Ethiopia /." Berne : Institute of Geography, 1994. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Jayasuriya, Rohan Terrence, and rohan jayasuriya@dpi nsw gov au. "Technological Change And Scarcity Of Soil In The Tea Sector Of Sri Lanka." La Trobe University. School of Business, 1998. http://www.lib.latrobe.edu.au./thesis/public/adt-LTU20070420.122921.
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This study analyses the technological change in the aggregate tea sector of Sri Lanka, by contributing to an understanding of total factor productivity change with assessment of the extent and nature of such changes from 1960/61 to 1994/95. The total factor productivity measures are then used to define a conceptually sound measure of the production cost of land degradation, providing insight into the scarcity of soil in the tea sector.
Total factor productivity in the tea sector, increased at an estimated annual rate of 1.82 percent during the study period. This resulted from an estimated annual rate of increase of 0.01 percent in total output and a considerably larger rate of 1.81 percent annual decrease in total input. Thus, the reason for total factor productivity growth was largely due to cost savings associated with decreased use of inputs rather than increased output. Land and capital inputs showed significant negative growth trends, confirming a lack of long-term investment in the tea sector. As expected, all the partial factor productivities showed increases over the study period due to lower use of those individual inputs; the most significant changes occurring in the partial productivities of land and capital inputs. The terms of trade and the returns to costs ratio, exhibited an annual rate of decrease of around 3.7 percent and 1.9 percent, respectively. The producer terms of trade growth rate of -3.7 percent, has been brought about by an estimated annual rate of increase in prices received of 10.6 percent compared with an increase of 14.3 percent in prices paid.
The Sri Lankan tea industry, once pre-eminent in the world, has been going through intermittent crises for a long time due to problems related to low productivity and the high cost of production. The management of the nationalised plantations proved inadequate to meet the task of adjusting to the new challenges of raising productivity and remaining competitive. The contribution of the tea industry to the economy declined. Among other causes, stagnating crop productivity was found to be an important factor. Land degradation in the form of soil erosion, was found to be a serious problem for the entire tea sector.
Careless and ecologically unbalanced agricultural practices, have over the years, led to varying degrees of degradation of the tea soils. However, these physical measures of land degradation do not necessarily reveal an economic or social problem.
In the second part of the study, an attempt is made to quantify the impact that land degradation has on tea production. Based on the theoretical relationship of the impact of technological progress and land degradation on tea production, a regression model was fitted to deconstruct the total factor productivity variable. The objective of this approach is to find an economic value for land degradation by quantifying the extent of this impact on aggregate tea production in Sri Lanka. One of the key points to come out of this estimation exercise, is the difficulty of isolating the impact of individual factors on measured total factor productivity. On the basis of available data and the chosen model, it could be concluded that the impact of technological progress has outweighed the negative effect of land degradation in the tea sector, over the study period. Considering the fact that investment in tea research is mainly on developing varieties of vegetatively propagated clonal tea, and the associated very long gestation periods involved, a much larger lag length of the order of 25-35 years is recommended for the research investment variable, to enable calculation of the marginal internal rate of return to public investment in tea. Importantly, a larger set of data will become available over the next decade or so which will enable appropriate lags to be incorporated in future research on productivity in the tea industry.
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Kakembo, Vincent. "A reconstruction of the history of land degradation in relation to land use change and land tenure in Peddie district, former Ciskei." Thesis, Rhodes University, 1997. http://hdl.handle.net/10962/d1005523.
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A history of land degradation is reconstructed in a part of the dividing ridge between the Great Fish and Keiskamma rivers, in Peddie District, former Ciskei. The study entails a comparative investigation of the progressive changes in land use, vegetation and soil erosion in three tenure units, namely: former commercial farms, traditional and betterment villages. Analysis of the sequential aerial photography of the area for 1938,1954, 1965, 1975 and 1988 is employed. This is backed by groundtruthing exercises. Data thus obtained are quantified, and linkages between degradation, anthropogenic and physical factors are derived using PC ARC/INFO GIS. Differences in land tenure systems emerge as the main controlling factor to variations in land degradation. Confinement of vegetation diminution and erosion to traditional and betterment villages is observed at all dates. Scantily vegetated surfaces and riparian vegetation removal are a characteristic feature of both areas throughout the study period. 'Betterment,' introduced in the early 1960s to curb land degradation is, instead observed to exacerbate it, particularly soil erosion. Trends in land use change are characterised by the abandonment of cultivated land, which is noted to coincide with a sharp rise in population. Erosion intensification into severe forms particularly between 1965 and 1975, coincident with a period of extreme rainfall events, emerges as the most significant degradation trend. A close spatial correlation between abandoned cultivated land and intricate gullies is identified. So is the case between grazing land and severe sheet erosion. Within the grazing lands, an examination of erosion and categories of vegetated surfaces reveals that erosion occurs predominantly on the scanty vegetation category. Such erosion-vegetation interaction largely explains the non-recovery of the scanty vegetation category, even during periods of intense rainfall. Extensive channel degradation is evident along stream courses with scanty riparian vegetation. Physical factors are noted to have a significant bearing on erosion. The high prevalence of erosion on the Ecca group of rocks confirms its erosion-prone nature. Pockets of colluvium and alluvium accumulation in the steep bottomlands are identified as the sites of the most severe gully erosion. Field surveys at some of the sites indicate that a dolerite sill through the area forms a boundary of colluvium accumulation and the upslope limit to gully incision. That these sites are recognised as formerly cultivated land, portrays the interaction between physical and anthropogenic variables with regard to inducing degradation in the area.
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Dickie, Jennifer Ann. "Relationships among the physical and chemical properties of soil, vegetation and land degradation in semi-arid environments." Thesis, University of Leicester, 2006. http://hdl.handle.net/2381/30410.
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This study examines the spatial patterns of soil parameters to test the hypothesis that shrub encroachment initiates a change in scale of soil heterogeneity, which consequently influences a landscape's biotic and abiotic interactions and thus the susceptibility of soil to erosion. Grassland, shrubland and badland sites were established in two semi-arid environments; the Karoo, South Africa and the Sevilleta National Wildlife Refuge, New Mexico, U.S. 108 soil samples from each of the eleven 60m x 60m plots were analysed for bulk density, shear strength, texture, aggregate stability, organic matter content, pH, conductivity and available sodium, calcium, magnesium, potassium and phosphorus content. Geostatistical analyses determined that, at a scale representative of the vegetation community, the grassland landscape appeared relatively homogeneous in its distribution of soil parameters. Shrublands, however, demonstrated an increase in heterogeneity of all soil parameters. Periodicity in the semi-variograms indicated that regular patterns across the landscape were evident for all parameters and thus likely to represent the differences between shrub and intershrub regions. Due to the complex plant-soil interactions, and the interactions amongst the soil parameters themselves, the cyclic patterns represent areas of high and low erodibility. More pronounced patterns were identified in the badlands. This indicates that, if the conditions are right, changes in plant-soil interactions caused by soil parameter redistribution in shrubland landscapes can exacerbate erosion leading to further degradation in the form of badlands. Comparisons between the two semi-arid regions suggest that although local variations in soil type and different species of vegetation will affect the intensity of the spatial response, the underlying patterns are similar at both locations and hence, potentially, at a global scale.
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Morel, Anneke. "Soil erosion and land degradation in the Swartland and Sandveld, Western Cape province, South Africa : a re-evaluation." Master's thesis, University of Cape Town, 1998. http://hdl.handle.net/11427/9681.
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Bibliography: leaves 140-151.The Swartland and Sandveld are situated in the Western Cape province (political limits) in what is also known as the southwestern Cape region . This area falls within the winter rainfall (or Mediterranean) region of South Africa and has a sharply defined seasonal climate. Vegetation in the region is unique. The soils in the Swartland and Sandveld vary greatly over short distances, making this area vulnerable to varying erosion rates. Land use in the Swartland and Sandveld is mainly agricultural. Soil erosion is driven by the force of wind and or water. Sheet flow is what is considered as unconstrained water erosion together with rainsplash, while piping, rill and gully erosion are all forms of constrained water erosion. Erosivity and erodibility are both important factors in determining the vulnerability of an area to soil erosion. By their understanding of the factors involved in the course of degradation, researchers can determine the most effective conservation policies for a region. Of course, the influence of humans on the land should never be under-estimated and should be seen as a potent determinant of the erosion potential. The use of remote sensing and G.I.S. are essential in the development of erosion maps, and to assess possible changes that over time in the erosional situation in a region. As an analytical and data storage tool, these techniques are very useful, even essential. The total decrease in gully erosion from 1938 to 1989 in the Swartland amounts to 85% compared to the gully erosion in 1938. In the Sandveld wind erosion decreased with 17% from 1928 to 1986. Soil conservation in South Africa has come a long since the 1930's and much of the experience and the lessons gained in the last six of seven decades have been incorporated in the countries new conservation Act. It has been concluded that the slowing down of the denudation process in the region, coinciding with effective new conservation strategies, are the principal reasons for the results obtained in this research project. It must be noted however that without the intervention of the conservation efforts in the Swartland and Sandveld, the remarkable improvement in the water erosion situation (85%) would not have been obtained. The overall improvement (17%) in the Sandveld lags that in the Swartland and even shows a slight deterioration of the wind erosion situation found in 1974. There are therefore grounds for caution, since wind erosion is still very much relevant and not fully contained in the Sandveld. Further research into this situation would indeed be beneficial.
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Heckman, John Richard. "Restoration of Degraded Land: A comparison of Structural and Functional Measurements of Recovery." Diss., Connect to this title online, 1997. http://scholar.lib.vt.edu/theses/available/etd-1416152839711171/.
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Mulumba, Lukman Nagaya. "Land use effects on soil quality and productitivity in the Lake Victoria Basin of Uganda." The Ohio State University, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=osu1095711869.
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Mendonça, Izaque Francisco Candeia de. "Adequação do uso agricola e estimativa da degradação ambiental das terras da microbacia hidrografica do riacho Una, Sape-PB." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257244.
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Orientador: Francisco Lombardi NetoTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola
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Resumo: A crescente expansão das atividades agropecuárias, sem considerar as potencialidades e limitações das terras constitui fonte potencial de degradação do meio ambiente. Este trabalho objetiva avaliar o meio físico das terras da Microbacia Hidrográfica do Riacho Una, Sapé-PB, com determinação das taxas de adequação de uso das terras a partir das classes de capacidade de uso e determinar sua degradação ambiental, no contexto do modelo da Equação Universal de Perda de Solo - EUPS e a partir da aplicação dos diagnósticos físico-conservacionista, sócio-econômico e ambiental. A área localiza-se na porção leste do Estado da Paraíba entre as coordenadas geográficas: 35º08¿16¿ a 35º15¿12¿ de longitude, a oeste de Greenwich e 06º59¿18¿ a 07º05¿42¿ de latitude sul. Os procedimentos realizados utilizam-se de técnicas de geoprocessamento, sendo a integração de informações realizada no Sistema de Informações Geográficas Idrisi Kilimanjaro versão 14.0. A adequação do uso foi obtida ao se cruzarem às informações do plano de capacidade de uso da terra com o uso atual, definindo-se três classes: Adequado, Inadequado (Sobreutilização) e Áreas de Preservação. Na avaliação do potencial agrícola foi encontrado que 61,9% da área estão sendo utilizados adequadamente, 20,4% com uso atual acima da oferta ambiental avaliada (sobreutilizados) e 14,9% estão ocupados com cobertura vegetal, constituindo as áreas de preservação. A classificação do risco atual de degradação das terras, por erosão do solo, revelou que em 92,9% da área da microbacia o risco é muito baixo. E apenas 1,5% da área de estudo as terras estão incluídas nas classes alta e muito alta de risco de erosão. Na estimativa da degradação ambiental pela aplicação dos diagnósticos físico-conservacionista, sócio-econômico e ambiental, constatou-se uma degradação de ambiência de 34,4%, representando 2406,26 ha da área avaliada. É notória a influência do aspecto sócio-econômico na degradação da microbacia, com uma média de 61,3%. Os resultados obtidos demonstraram que a Microbacia Hidrográfica do Riacho Una apresenta um ambiente com boas qualidades agroambientais, caracterizadas pela baixas expectativas de processos erosivos e a indicação de aproximadamente 60% de terras aptas para uso agrícola
Abstract: Increasing in expansion of agricultural activity without take into account land potentiality and restrictions is currently a potential source for environment degradation. This present work aims to evaluate some physical characteristics of lands from Watershed of Una Rivulet in Sapé, PB, Brazil, by utilizing the soil use capability classes, and to determine its environmental degradation into the context of Universal Soil Loss Equation ¿ USLE and from the use of physical-conservationist, socioeconomic and environmental diagnosis informations. The area is located at the east sector of Paraiba State between the following geographic coordinates: 35º08¿16¿ -35º15¿12¿ longitude, west of Greenwich and 06º59¿18¿ - 07º05¿42¿ south latitude. The accomplished procedures draw on geoprocessing system and the integration of achieved informations has utilized the geographic information system Idrisi Kilimanjaro version 14.0. Crossing informations of land use capacity and current use had utilized been as a means to determine for adequateness of land utilization then to define the following three main class of land use: adequate, inadequate and areas of preservation. In the evaluation of the land agricultural potentiality it was found that 61,9% of the area is being utilized adequately, 20,4% is utilized above of its predictable environmental capability and finally 14,9% is found to keep vegetal covering and is taken as preservation area. The classification of the current risk for land degradation, due to soil erosion, has revealed it to be very low in about 92,9% of the area of watershed. And no more than 1,5% of lands at that area is into the class of high to very high risk of erosion. In the estimations of the environmental degradation, by utilizing the physical-conservationist, socio-economic and environmental diagnosis, there have ambience degradation of by 34,4% and it represents by 2406,26 ha of the studied area. The impact from socio-economic factors with regard degradation of watershed is well known and is around of 61,3%. The data show that Watershed of Una Rivulet presents good agro-environmental qualities, which are characterized through a low expectation for soil erosion and the fact that 60% of its soils can be well utilized for agricultural practices
Doutorado
Planejamento e Desenvolvimento Rural Sustentável
Doutor em Engenharia Agrícola
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Manyevere, Alen. "An integrated approach for the delineation of arable land and its cropping suitability under variable soil and climatic conditions in the Nkonkobe municipality, Eastern Cape, South Africa." Thesis, University of Fort Hare, 2014. http://hdl.handle.net/10353/d1019856.
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Arable crop production in Nkonkobe Municipality is low due to abandonment of potentially productive land and low productivity of the cultivated land. Little attention has been given to farmers perspectives with regards to crop production and land abandonment. Understanding the relationships of indigenous knowledge systems, where local approaches to soil classification, appraisal, use and management and land evaluation, and scientific approaches could be important for the effective use of available soil resources while avoiding those resources that are vulnerable to degradation. In addition, the interactions between soil factors and climate could be useful in understanding the erodibility of soils. The intergration of scientific research and indigenous knowledge systems could help in the identification and delineation of high potential land and on crop suitability evaluation. The objectives of the study were: (i) to determine farmers‟ perspectives with regards to land utilisation and abandonment, constraints on crop production and crop preferences, (ii) to integrate and compare indigenous knowledge systems with scientific approaches of soil classification and potential, (iii) to determine the effect of climate and soil factors on erodibilities of soils in the Municipality (iv) to delineate arable land and evaluate its suitability for maize, potato, sorghum and cowpea under rainfed agriculture. Using semi-structured and open-ended interviews, information on limitations to crop production, cropping preferences, indigenous soil classifications, cropping potential ratings and erosion was captured. Descriptive and correlation statistics were used to analyse farmers‟ responses. The information was later used for a pilot participatory mapping and the determination of the agricultural potential of the soils in three selected villages of the Municipality. Field boundaries of soil texture, colour, depth, and slope position were captured using global positioning systems (GPS). The relationship between the degree of erosion and soil and slope factors was analysed by step-wise regression. Crop suitability for rainfed agriculture was done using the FAO guidelines for Land evaluation for rainfed agriculture. The spatially referenced crop suitability classes were produced by applying the Law of Limiting Combinationusing GIS Boolean Logic. The major biophysical factors, affecting crop production and land utilisation were soil degradation and low and erratic rainfall, while other factors included lack of farming equipment and security concerns. Maize, spinach and cabbage were the main crops grown, with maize sorghum and wheat the most abandoned crops. While it was difficult to accurately correlate indigenous classification with international scientific classification, the importance of colour, texture and soil depth for both classification and soil potential, suggests that some form of correlation is possible which enabled communication and other extension information to be conveyed. The shallow and stony soil (urhete) correlated well with the Leptosols in World Reference Base (WRB) or Mispah and shallow Glenrosa soils in the South African system. The red structured clays (umhlaba obomvu) matched the Nitisols in WRB or Shortlands in the South African system. The non-swelling black clayey soils (umhlaba omnyama) matched soils with melanic A horizons in both the WRB and South African soil classification systems. The dongwe and santi soils developed in alluvial sediments belonged to the Dundee, Oakleaf or Augrabies soils in the South African classification system and fluvisols or Cambisols in the WRB system. There was good agreement between farmers assessment of the cropping potential and scientific approaches but scientifically high potential red soils were rated lowly by the farmers due to difficulties in management caused by shortages of farm machinery, especially under dryland farming. Overall, the soil factors affecting erosion were influenced largely by climate, while parent material was also important. Climate had a dominant influence on soil factors most notably fine sand and very fine sand fractions and exchangeable sodium percentage being more important on soil forms occurring in arid and semi-arid climate and less in the sub-humid and humid areas, where clay mineralogy, particularly kaolinite and sesquioxide dominated. Dolerite derived soils were the most stable and should be given the highest priority for cropping development while mudstone and shale derived soils had a lower cropping potential. While slope gradient and length had some effect on soil erosion in arid and semi arid environments its influence was generally overshadowed by soil factors especially in humid zones. Cow pea and sorghum were the most adapted crops in the region while potato and maize were marginally suitable under rainfed agriculture. The study revealed that most adapted crops were not necessarily the most preferred crops by the farmers. A small percentage of the land was delineated as arable and therefore optimisation of this available land should be prioritized.
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Cruz, Ricardo Decker da. "Análise Espacial da Degradação Ambiental no Municipio de Capão do Leão, RS." Universidade Federal de Pelotas, 2011. http://repositorio.ufpel.edu.br/handle/ri/1132.
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Previous issue date: 2011-09-08The nowadays model of development has as a basic principle an economically based growth focused in the technological development, having the GIP as the main indicator of development of a nation. This model is known for promoting an accelerated degradation of the quality of the environment under pressure. The present work aims the identification; quantification and classification of the severely degraded land in the Capão do Leão municipality RS, Brazil, through the use of geotechnologies. In order to achieve that, the following base layers were used: roads, hydrography, river basins, numerical terrain model, vegetation, geology, soils, and degraded land. The degraded land areas were identified and delineated in Google Earth images and subsequently characterized in the field. Through the degraded land data collected a land degradation classification scheme was conceived based on the causing agent, degradation degree, the activity status of the degrading agent, and the possibility and type of reclamation needed. Crossing the land degradation database with the other base maps generated new maps and information. A number of 746 degraded areas were identified, varying in size, shape and degree, totaling 474,9ha of severely degraded land, mostly due to mine activities (361,4 ha or 76% of the total) - sand, granite and gravel. Other important type of degradation were those of borrow materials (61,8 ha 13% of the total). Soil units more affected were those of Entisols and Ultisols, due to granite and gravel mining, respectively, and of Spodosols, located in the São Gonçalo plain, due to sand mining. From the total degraded areas, 224,7ha in 69 occurrences are in an extremely degree of degradation under strong or very strong erosive activity, needing a restoration that includes a continuous intervention with reconditioning of the surroundings, that in some cases may need a change of use.
O modelo atual de desenvolvimento tem como princípio básico o crescimento acelerado centrado no desenvolvimento tecnológico, um modelo de base econômica, sendo o PIB o principal indicador de desenvolvimento de uma nação. Esse modelo comprovadamente promove uma acelerada degradação da qualidade ambiental dos meios pressionados. O presente trabalho tem como objetivo identificar, quantificar e classificar a degradação ambiental severa no município de Capão do Leão, através do uso de geotecnologias. Para tal, foram utilizados os seguintes planos básicos de informação: base cartográfica (malha viária), hidrografia, bacias hidrográficas, Modelo Numérico do Terreno (MNT), vegetação, geologia, solos e áreas degradadas. As áreas degradadas foram identificadas a partir de imagens disponíveis do Google Earth e caracterizadas em campanhas de campo. A partir dos planos básicos foram gerados outros planos de informação como o mapa de declividades, de altitude e os cruzamentos com as áreas degradadas. A partir da integração dos dados foi elaborada uma classificação para as áreas degradadas no município cujas diretrizes basearam-se no agente causal, grau de degradação, status da atividade causadora da degradação e possibilidade e tipo de recuperação. Foram identificadas 746 áreas degradadas, variáveis em tamanho, forma e intensidade. Em termos globais encontrou-se um total de 474,9ha de áreas severamente degradadas, destacando-se aquelas ligadas as minerações (361,4ha ou 76% do total), de areia, granito e saibro, além de áreas de empréstimo (61,8 ha 13% do total), principalmente para barragens e estradas. As unidades de solos mais afetadas foram as de Neossolos Litólicos e de Argissolos, nas terras altas, por mineração de granito e saibro, respectivamente, e de Espodossolos, na planície do São Gonçalo, por mineração de areia. Das 746 áreas identificadas, 69 (224,27ha ou 47%) encontram-se em grau de degradação extrema com atividade erosiva forte ou muito forte, necessitando de uma recuperação que envolva uma intervenção continuada com conformação de entorno, podendo haver necessidade de redirecionamento de uso.
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Marz, Michael Verfasser], Manfred [Akademischer Betreuer] [Frühauf, Heinz [Akademischer Betreuer] Beckedahl, and Christian [Akademischer Betreuer] Opp. "Identification and assessment of driving forces of land and soil degradation in the South African province of KwaZulu-Natal and the Kingdom of Swaziland / Michael Marz ; Manfred Frühauf, Heinz Beckedahl, Christian Opp." Halle, 2016. http://d-nb.info/1120410045/34.
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Kaati, Patrik. "Small-Scale Farmers Land Use and Socioeconomic Situation in the Mount Elgon District in Northwestern Kenya : A Minor Field Study - Combined Field Mapping and Interview." Thesis, Högskolan Dalarna, Geografi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:du-10161.
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This Minor Field Study was carried out during November and December in 2011 in the Mount Elgon District in Western Kenya. The objective was to examine nine small-scale farming household´s land use and socioeconomic situation when they have joined a non-governmental organization (NGO) project, which specifically targets small-scale farming households to improve land use system and socioeconomic situation by the extension of soil and water conservation measures. The survey has worked along three integral examinations methods which are mapping and processing data using GIS, semi structured interviews and literature studies. This study has adopted a theoretical approach referred to as political ecology, in which landesque capital is a central concept. The result shows that all farmers, except one, have issues with land degradation. However, the extent of the problem and also implemented sustainable soil and water conservation measures were diverse among the farmers. The main causes of this can both be linked to how the farmers themselves utilized their farmland and how impacts from the climate change have modified the terms of the farmers working conditions. These factors have consequently resulted in impacts on the informants’ socioeconomic conditions. Furthermore it was also registered that social and economic elements, in some cases, were the causes of how the farmers manage their farmland. The farmer who had no significant problem with soil erosion had invested in trees and opportunities to irrigate the farmland. In addition, it was also recorded that certain farmers had invested in particular soil and water conservation measures without any significant result. This was probably due to the time span these land measures cover before they start to generate revenue. The outcome of this study has traced how global, national and local elements exist in a context when it comes to the conditions of the farmers´ land use and their socioeconomic situation. The farmers atMt.Elgon are thereby a component of a wider context when they are both contributory to their socioeconomic situation, mainly due to their land management, and also exposed to core-periphery relationships on which the farmers themselves have no influence.
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Mndela, Mthunzi. "Evaluation of range condition, soil properties, seed banks and farmer's perceptions in Peddie communal rangeland of the Eastern Cape, South Africa." Thesis, University of Fort Hare, 2013. http://hdl.handle.net/10353/d1013153.
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South African rangelands in combination with their surrounding homesteads occupy 13% of the entire land surface in South Africa. These rangelands are a source of forage for communal livestock. The rangelands in communal tenure system are degraded due to high human population and livestock numbers. The rangeland of Peddie was never evaluated since the introduction of Nguni Cattle Empowerment Project. Therefore, socio-ecological evaluation was conducted in order to interlink farmer‟s perceptions and scientific data to recommend appropriate rangeland management and restoration programme. Two structured questionnaires consisting of close and open ended questions were used to investigate farmer‟s perceptions on rangeland condition, dynamics, and their causes. Sixty households were randomly selected on the bases of livestock ownership and the membership in Nguni Cattle Project. In each household, any respondent of 20 years or greater, and a key informant of age greater than 40 years were selected. For scientific assessment of range condition, three homogenous vegetation units namely grassland, scattered and dense bushland were demarcated into four 100m x 50m replicates. In each replicate, two 100m transects were laid parallel to each other with 30m equidistant apart. The step point and harvesting method along each transect were employed for herbaceous species composition and biomass production. The point-to-tuft distance was also determined as a proxy for basal cover. Woody density, species composition and tree equivalents were determined in 200m2 belt transects in each HVU replicates. The germination method for soil seed bank evaluation was also employed to find plant species composition and density. The soil nutrients (OC, N, P, K, Na, Ca, Mg, Zn, Cu and Mn) and pH were analysed through solution preparation and observation under photospectrometer to determine functional capacity of the soil of Peddie rangeland. The farmer‟s perceptions comprised of 63% females and 37% males (n = 120) with a mean household of 8 people, 5 adults and 3 children. It was perceived by 93.3% respondents that the rangeland of Peddie have undergone changes over two decades. These changes were perceived by 83% respondents to be accompanied by decline in livestock numbers. Woody encroachment and overgrazing were perceived to be the major attributes of these vegetation changes. The scientific rangeland condition assessment confirmed that these changes were more pronounced as bush density increases. Dense bushland had a significantly high (p<0.05) encroached condition with 6650 trees ha-1 and 4909.5 TE ha-1 beyond the recommended thresholds of 2400 trees ha-1 and 2500 TE ha-1 respectively. Scattered bushland had a fair condition of 1950 trees ha-1 and 1198.1TE ha-1. Themeda triandra as a key species was significantly higher (p<0.05) in grassland (31.1%) than scattered (15.6%) and dense bushland (6.1%). There was a declining trend in biomass production from grassland to dense bushland. The summer biomass production was significantly higher (p<0.05) in grassland than scattered and dense bushland but winter biomass was not significantly different (p>0.05) from all homogenous vegetation units of Peddie rangeland. However, the soil fertility increased with an increase in bush density except organic carbon (OC) which was 1.61% in grassland, 1.46% in scattered and 1.53% in dense bushland respectively. Soil N, K, P, Mg2+ Na+, Ca2+, Cu, Zn, Mn and pH were significantly higher (p<0.05) in dense bushland than grassland and scattered bushland. High soil fertility in dense bushland may be attributed to by abscission of woody plants and litter decomposition. In the soil seed bank, the abundances of forbs were significantly higher than sedges (χ2 = 12, df = 1, p = 0.001) and grasses (χ2 = 8.333, df = 1, p = 0.004) in all homogenous vegetation units while sedges were not significantly different (χ2 = 3, df = 1, p = 0.083) from grasses. The Sorensen‟s index indicated that soil seed bank and extant vegetation were significantly different (p<0.05). Annual and biennial forbs and sedges had high abundances while perennial grasses formed a bulk in above ground vegetation. This provided an insight that a reliance on soil seed bank for restoration of Peddie rangeland would not be advisable because it can result in retrogression. The communal rangeland assessment provided clear qualitative and quantitative data when the combination of indigenous knowledge and scientific assessments was done. The rationale is that conclusions and recommendations of range assessment are relient on the farmer‟s perceptions pertinent to their livestock production systems and their rangeland management objectives. This study has shown that inclusion of communal farmers in policy making can provide better insight because those are the people experiencing the consequences of range degradation.
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Mesquita, Marisa Vianna [UNESP]. "Degradação do meio físico em loteamento nos bairros Invernada, Fortaleza e Água Azul, como estudos de casos da expansão urbana do município de Guarulhos (SP)." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/102944.
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mesquita_mv_dr_rcla.pdf: 3083423 bytes, checksum: 7fa330af93c3069c5c45b2d857c6eb02 (MD5)O município de Guarulhos, segunda maior cidade em população no Estado de São e pertencente à Região Metropolitana de São Paulo - RMSP vem sofrendo uma ocupação acelerada e desordenada ao longo de décadas. Dividido fisiograficamente em dois macrocompartimentos, separados pela Falha do Rio Jaguarí, Guarulhos possui na sua porção sul uma área já consolidada com terrenos mais apropriados à ocupação e com mais facilidade de acesso a serviços e infraestrtura. As áreas com problemas encontram-se na porção norte do município, que além de serem áreas com presença de declividades acentuadas, são ocupadas irregularmente, carentes em infraestrutura e planejamento do Poder Público. Resultado da pressão de ocupação na porção norte do município foram analisados três microbacias pertencentes aos Bairros Invernada, Fortaleza e Água Azul que possuem ocupações com históricos diferentes resultando ao longo do tempo em degradações ambientais principalmente no que se refere à dinâmica superficial. Para elaboração do Mapa de Degradação Ambiental para as três microbacias foram utilizados: o método de sobreposição de informações do IPT (2004) para as Microbacias Taquara do Reino (Bairro Invernada) e Guaraçau (Bairro Água Azul) e o método de Unidades Básicas de Compartimentação (UBCs) de Vedovello (2000) para a microbacia Lavras (Bairro Fortaleza). Os dados obtidos indicam que as três microbacias sofrem com a degradação ambiental, materializada em problemas de dinâmica superficial como escorregamentos nas regiões declivosas e um grande volume de assoreamentos, principalmente nas planícies aluvionares. A falta de planejamento e de infraestrutura nesses bairros corroboram para um aumento dessa degradação necessitando de cartografia geotécnica que possa auxiliar o Poder Público na melhor forma de uso do solo e a gerenciar os problemas existentes
The municipality of Guarulhos, second large in population, state of São Paulo belongs to the RMSP - Metropolitan Region of São Paulo, has suffered from a disorderly and accelerated occupation during the decades. Fisiogeographically divided in two macro compartments, separated by Jaguari River Fault, Guarulhos has in its South portion a well done consolidated area more appropriate to land occupation resulting in facilities to access services and infrastructure as well. The biggest problems are in the Northern-part that beyond to be areas with an accentuated declivity, are irregularly occupied with no infrastrueture or governmental assistance planning. Due to the occupation stress in the Northern portion were analyzed three micro basins belonging to the Invernada, Fortaleza and Agua Azul Quarters with different historical occupations resulting in a short term in an environmental degradation especially regarding to dynamie surface. To elaborate the three micro basins Environmental Degradation Map were used two methods: overlaping information for the micro basins applied for Taquara do Reino (Invernada Quarter) and Guaraçau (Água Azul quarter) and the Compartimentation Basie Units methods applied to the Lavras micro basin (Fortaleza Quarter). The obtained datas suggest that the three basins suffer with the environmental degradation revealed in dynamic surface problems such as slide, a great volume of silting, mainly of the alluvial plains. The absence of planning and infrastructures in these places assure to an increase of this degradation, requiring geotechnical cartography in order to help the government to go on in a best way to use the land and manage the existing problems
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O'Brien, Patricia Ann, and patricia o'brien@rmit edu au. "COncepts and costs for the maintenance of productive capacity: a study of the measurement and reporting of soil quality." RMIT University. Accounting and Law, 1999. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20040930.170346.
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This thesis studies the role accounting plays in the monitoring and reporting of soil quality in one sector of the agricultural industry, broadacre farming. A survey was conducted with broadacre farmers in the Loddon Catchment, Victoria, Australia. The primary aim was to determine the effectiveness accounting plays in providing information to decision makers relative to the productive capacity in soil quality and not just on profits. The capital asset in this study was defined as soil quality. Soils and soil quality in particular, are major elements in determining land value. The concern is decisions are being made by potential buyers and other decision makers, particularly policy makers, with regards to soil quality on the basis of incomplete and often misleading information. It is proposed that a major reason is due to the fact that different participants in the agricultural and accounting industries require and use different information. The accounting systems used by farmers are those that have been developed for the manufacturing sector which may not be appropriate for managing long-term, complex resources such as soil. The farmers themselves did not find formal accounting reports useful for decision making because these reports are based on uniform standards and market prices. The topic of soil quality and land degradation is viewed from two perspectives. In one perspective, the proprietary view; the accounting emphasis is on the ownership of assets and the change, both in income and capital, in these assets over time. In this case the accounting equation is seen as assets - liabilities = equities. The proprietor takes all the risk. A more recent perspective in accounting, the entity view, emphasises the assets whether financed from equity or debt and where the accounting equation is seen as assets = equities. The emphasis changes to the income flow from these assets and more interest is shown in current market prices as a reflection of the future value of these assets Profit is not necessarily a good indicator of what farmers are doing for their capital asset. There needs to be greater emphasis on costs undertaken for the conservation of soil. Those costs should be considered an investment and put into the balance sheet and not the profit and loss statement. The major finding of study demonstrates that decision making groups have different
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Santos, Jaime Augusto Alves dos. "Saberes de solos em livros didáticos da educação básica." Universidade Federal de Viçosa, 2011. http://locus.ufv.br/handle/123456789/5496.
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Previous issue date: 2011-02-21Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The discussion around the need for soil conservation does not usually part of the daily concerns of the people, and this can lead to continued growth of environmental problems related to land degradation. These problems may be associated with lack the majority of the population has the features, functions and importance of soil. You need to develop actions that lead people to understand the soil as part of the environment and raise awareness about its importance. These actions can be initiated and undertaken in schools in order to awaken and promote awareness of students in relation to soil, because if topics are best worked out in the first years of basic education, it is possible to (re) build the values and attitudes that can help to mitigate land degradation. In most schools teachers use the Textbook as main and sometimes the only material support in the classroom and that makes him one of the determinants of educational quality. In this context it is necessary to investigate and verify the themes of soils in textbooks of basic education. The research aimed to examine the topic in textbooks soils offered by MEC through the National Textbook and adopted in public schools in Viçosa / MG, and verify that the content displayed in the books meets the guidelines proposed by the National Curriculum Parameters (PCN ). The choice of criteria for analysis of themes in the books soil had as reference the NCP, that link the content to be covered in each year of elementary school. After analyzing the NCP found that issues related to soils are discussed with emphasis in the discipline of science. The analysis showed that there Textbooks omission of content in some works. The quantitative evaluation showed that the space devoted to soils in textbooks is greatly reduced. The textbook should not be the only material to be used by teachers, this points to the need for development of educational materials and activities with concepts and updated consistent with the day-to-day lives of students. As well as supporting materials for teachers who do not always have an initial training or continuing around the themes of soils.
A discussão em torno da necessidade da conservação do solo não faz, geralmente, parte das preocupações diárias das pessoas, e isso pode levar a um crescimento contínuo dos problemas ambientais ligados à degradação dos solos. Estes problemas podem ser associados ao desconhecimento que a maior parte da população tem das características, importância e funções dos solos. É preciso desenvolver ações que levem a população a compreender os solos como parte do ambiente e conscientizar sobre sua importância. Essas ações podem ser iniciadas e desenvolvidas nas escolas, de forma a despertar e promover a consciência dos estudantes em relação aos solos, pois se os temas forem melhor trabalhados já nos primeiros anos da educação básica, é possivel (re)construir valores e atitudes que possam contribuir para atenuar a degradação dos solos. Na maioria das escolas os professores utilizam o Livro Didático como principal e as vezes o único material de apoio em sala de aula e isso o torna um dos determinantes da qualidade do ensino. Nesse contexto é necessária a investigação e ver ificação dos temas de solos nos livros didáticos da educação básica. A pesquisa teve como objetivo analisar o tema solos nos livros didáticos oferecidos pelo MEC através do Programa Nacional do Livro Didático e adotados nas escolas públicas de Viçosa/MG, e verificar se o conteúdo exposto nos livros atende as orientações propostas pelos Parâmetros Curriculares Nacionais (PCN). A escolha dos cr itérios para análise dos temas de solos nos livros tiveram como referencial os PCN, que apontam os conteúdos que devem ser abordados em cada ano do ensino fundamental. Após a análise dos PCN constatou-se que os temas relacionados aos solos são abordados com maior ênfase pela disciplina de ciências. A análise dos Livros Didáticos demonstrou que há omissão de conteúdos em algumas obras. A avaliação quantitativa apontou que o espaço dedicado aos solos nos Livros Didáticos é bastante reduzido. O livro didático não deve ser o único material a ser utilizado pelos professores, isto aponta a necessidade de elaboração de materiais didáticos com conceitos e atividades atualizadas e condizentes com o dia-a-dia dos alunos. Assim como materiais de apoio aos professores que nem sempre tem uma formação inicial ou continuada a cerca dos temas de solos.
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Giboshi, Monica Luri. "Sistema de apoio ao processo de decisão para a gestão do uso agricola da terra." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257241.
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Orientadores: Luiz Henrique Antunes Rodrigues, Francisco Lombardi NetoTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola
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Resumo: Este trabalho teve como objetivo o desenvolvimento de um sistema de apoio à decisão para a gestão da terra, integrando um Sistema Especialista para determinar a capacidade de uso da terra e outro para recomendar usos adequados e as práticas de conservação e manejo do solo, um Sistema de Informações Geográficas (SIG), uma base de dados e uma interface para interpretar a entrada de dados do usuário e as mensagens passadas entre os sub-sistemas. Todos os diálogos entre o usuário e o sistema são realizados pela da interface, assim como a comunicação entre os componentes do sistema desenvolvido. Os sistemas especialistas foram desenvolvidos utilizando o ¿shell¿ conhecido como CLIPS (C Language Integrated Production System) que provê um ambiente para a construção de sistemas especialistas. O SIG utilizado foi o IDRISI, versão 32, que possui o módulo Applications Programming Interface - API (Interface de Programação de Aplicativos) com um OLE Automation Server, possibilitando o uso de linguagens de alto nível, tais como Visual Basic, para controlar as operações do Idrisi32. A base de dados foi desenvolvida com a utilização do Microsoft Access®, além disso, é de fácil acesso, pois a maioria dos usuários tem esse aplicativo instalado em seus computadores. O sistema desenvolvido determina a capacidade de uso da terra; recomenda usos adequados para cada classe de capacidade de uso; recomenda práticas de conservação e manejo do solo; e identifica áreas de conflito comparando os mapas de uso da terra da região em estudo com o mapa de capacidade de uso. Todos os resultados podem ser visualizados em janelas do programa, gravados ou impressos em formas de relatórios. A validação do sistema foi feita comparando as saídas do sistema com os resultados obtidos de quatro especialistas. As divergências encontradas mostraram que o sistema desenvolvido foi mais rigoroso, principalmente no que diz respeito ao risco de erosão, determinando classes de capacidade de uso diferentes das determinadas por alguns especialistas. Quanto ao tipo de uso e às práticas de conservação e manejo do solo, foram poucas as divergências encontradas. A área utilizada para testar o sistema é o Município de Santo Antônio do Jardim - SP. O sistema classificou 36,95% das terras do município como adequadas para a utilização com cultura anual ou perene; 42,69% são adequadas para pastagem e reflorestamento e 19,51% devem ser utilizadas para preservação ambiental. Outro resultado apresentado é o mapa de intensidade de uso, no qual pôde se observar que 48,50% do município está sendo utilizada de forma adequada; 31,82% com uso inadequado e, 14,06% apresenta subutilização. O sistema mostrou ser uma ferramenta poderosa e eficaz, permitindo avaliar uma região, dando suporte para uma tomada de decisão mais fundamentada
Abstract: The objective of this work was to develop a decision support system for agricultural land environmental planing, which integrates an Expert System to determine the land capability and other to recommend adequate uses and practices for soil conservation and management, Geographic Information System (GIS), a database and an interface to monitor input and output data and the messages passed between the subsystems. The management of all the system is made by an interface developed in Visual Basic, version 5.0. All the dialogues between the user and the system as well as the communication with the components of the system are made through the interface that shows windows, menus, dialog boxes, maps and reports in the screen. It saves the results in files and prints them. The expert systems were developed with a shell known as CLIPS (C Language Integrated Production System), that provides an environment for building expert systems. The GIS was IDRISI, version 32, that has Applications Programming Interface ¿ API with an OLE Automation Server, and makes possible to use high-level languages, such as Visual Basic for controlling the operation of Idrisi32. The database was developed with the Microsoft Access®, because of the majority of the users have this software installed in its computers. The developed system determines land capability from information stored in the database and, also supplied for the SIG, through the soil and slope maps; it recommends adequate uses for land capability class; it recommends practices for soil conservation and management and identifies conflict areas comparing the maps of land use with the land capability. All the results can be visualized by the user through windows of the program, recorded or printed in forms of reports. The validation of the system was done comparing the system outputs with the results obtained of four experts. The divergences have shown that the system was more rigorous than the experts, specially concerning the erosion risk, leading to different land capability classes from those determined for some experts, in some cases. Concerning to the type of practices for soil conservation and management, the divergences have been few. In order to test the system, the county of Santo Antônio do Jardim ¿ SP was selected. The system classified 36.95% of lands as adequate for the use with annual or perennial cultures; 42.69% are adequate for pastures and reforestation and 19.51% must be used for environmental preservation. Another presented result is the map of intensity use, through which could be observed that 48.50% of the lands are being used of adequate form; 31.82% of the lands presents inadequate use and, 14.06% presents under utilization. The system is a powerful and efficient tool, what makes it possible to evaluate a region and give support to a more adequate decision making
Doutorado
Planejamento e Desenvolvimento Rural Sustentável
Doutor em Engenharia Agrícola
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Mesquita, Marisa Vianna. "Degradação do meio físico em loteamento nos bairros Invernada, Fortaleza e Água Azul, como estudos de casos da expansão urbana do município de Guarulhos (SP) /." Rio Claro : [s.n.], 2011. http://hdl.handle.net/11449/102944.
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Orientador: Antonio Roberto SaadCoorientador: Antonio Manoel dos Santos Oliveira
Banca: José Eduardo Zaine
Banca: Eduardo Soares de Macedo
Banca: Claudio José Ferreira
Banca: Marcio Roberto Magalhães de Andrade
Resumo: O município de Guarulhos, segunda maior cidade em população no Estado de São e pertencente à Região Metropolitana de São Paulo - RMSP vem sofrendo uma ocupação acelerada e desordenada ao longo de décadas. Dividido fisiograficamente em dois macrocompartimentos, separados pela Falha do Rio Jaguarí, Guarulhos possui na sua porção sul uma área já consolidada com terrenos mais apropriados à ocupação e com mais facilidade de acesso a serviços e infraestrtura. As áreas com problemas encontram-se na porção norte do município, que além de serem áreas com presença de declividades acentuadas, são ocupadas irregularmente, carentes em infraestrutura e planejamento do Poder Público. Resultado da pressão de ocupação na porção norte do município foram analisados três microbacias pertencentes aos Bairros Invernada, Fortaleza e Água Azul que possuem ocupações com históricos diferentes resultando ao longo do tempo em degradações ambientais principalmente no que se refere à dinâmica superficial. Para elaboração do Mapa de Degradação Ambiental para as três microbacias foram utilizados: o método de sobreposição de informações do IPT (2004) para as Microbacias Taquara do Reino (Bairro Invernada) e Guaraçau (Bairro Água Azul) e o método de Unidades Básicas de Compartimentação (UBCs) de Vedovello (2000) para a microbacia Lavras (Bairro Fortaleza). Os dados obtidos indicam que as três microbacias sofrem com a degradação ambiental, materializada em problemas de dinâmica superficial como escorregamentos nas regiões declivosas e um grande volume de assoreamentos, principalmente nas planícies aluvionares. A falta de planejamento e de infraestrutura nesses bairros corroboram para um aumento dessa degradação necessitando de cartografia geotécnica que possa auxiliar o Poder Público na melhor forma de uso do solo e a gerenciar os problemas existentes
Abstract: The municipality of Guarulhos, second large in population, state of São Paulo belongs to the RMSP - Metropolitan Region of São Paulo, has suffered from a disorderly and accelerated occupation during the decades. Fisiogeographically divided in two macro compartments, separated by Jaguari River Fault, Guarulhos has in its South portion a well done consolidated area more appropriate to land occupation resulting in facilities to access services and infrastructure as well. The biggest problems are in the Northern-part that beyond to be areas with an accentuated declivity, are irregularly occupied with no infrastrueture or governmental assistance planning. Due to the occupation stress in the Northern portion were analyzed three micro basins belonging to the Invernada, Fortaleza and Agua Azul Quarters with different historical occupations resulting in a short term in an environmental degradation especially regarding to dynamie surface. To elaborate the three micro basins Environmental Degradation Map were used two methods: overlaping information for the micro basins applied for Taquara do Reino (Invernada Quarter) and Guaraçau (Água Azul quarter) and the Compartimentation Basie Units methods applied to the Lavras micro basin (Fortaleza Quarter). The obtained datas suggest that the three basins suffer with the environmental degradation revealed in dynamic surface problems such as slide, a great volume of silting, mainly of the alluvial plains. The absence of planning and infrastructures in these places assure to an increase of this degradation, requiring geotechnical cartography in order to help the government to go on in a best way to use the land and manage the existing problems
Doutor
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Breytenbach, Andre. "GIS-based land suitability assessment and allocation decision-making in a degraded rural environmen." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/16599.
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Thesis (MSc)--University of Stellenbosch, 2006.ENGLISH ABSTRACT: Rural development problems faced by the impoverished communities in the Transkei, South Africa, are numerous, and environmental degradation has already taken much of its toll. By working at a micro-catchment-level both the socio-economic and biophysical appreciation of the land resources were captured as encapsulated in the concept of resource management domains. Participatory decision-making allowed functional land use goals and evaluation criteria to be incorporated into computerised multi-criteria evaluation and multi-objective land use allocation models in order to reach an idealised or more sustainable land use situation. In the execution of the decision-making process seven procedural steps were followed, which are discussed in detail and applied in the case study. Synthesis of the results emphasised the envisaged rural planning potential of the methods used.
AFRIKAANSE OPSOMMING: In terme van plattelandse ontwikkeling staar talle probleme die behoeftige gemeenskappe van Transkei, Suid-Afrika, in die gesig en omgewingsdegradering neem ongehinderd sy tol. Deur op ‘n mikro-opvangsgebied vlak te werk kon beide die sosio-ekonomiese en biofisiese waarde van die gebied se hulpbronne bepaal word en uitgebeeld word in hulpbron bestuursdomeine. Deur deelnemende besluitneming is funksionele grondgebruiksdoelwitte en evaluasie kriteria gebruik in gerekenariseerde meervoudige kriteria evaluering en veeldoelige grondgebruiksaanwysingsmodelle ten einde die ideale of ‘n meer volhoubare grondgebruik situasie te verkry. Vir die uitvoering van die besluitnemingsproses is van sewe opeenvolgende stappe gebruik gemaak en die uitvoering daarvan word in diepte bespreek in hierdie gevallestudie. Sintese van die resultate het die potensiaal van hierdie beoogde landelike beplanningsmetodes beklemtoon.
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Solera, Maria Lucia. "Desenvolvimento e avaliação de modelos estruturais de bioengenharia de solos para revegetar talude de pilha de estéril na mineração a céu aberto." Universidade Estadual Paulista (UNESP), 2018. http://hdl.handle.net/11449/153396.
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A mineração representa um importante setor na economia promovendo diversos benefícios econômicos e sociais ao país. Ainda que apresente impactos positivos, os cenários da degradação originados pela atividade minerária causam impactos negativos ao meio ambiente, dificultando a recuperação da área degradada. Esta pesquisa discute a aplicabilidade da bioengenharia de solos como estratégia promissora para recuperar um talude de pilha de estéril. Esse talude está constituído por materiais de diferentes granulometrias, alta declividade e elevado índices de vazios, características físicas que podem afetar o desenvolvimento ou mesmo a recolonização da vegetação nativa por processos naturais de sucessão. Três modelos estruturais de bioengenharia de solos denominados de guirlanda, colmeia e retentor foram confeccionados para reter mistura de solo-substrato/sementes de Crotalaria juncea, Mucuna aterrina e Cajanus cajan como adubos verdes visando à produção de matéria orgânica e promover as condições necessárias para posterior revegetação do talude. Os resultados obtidos com aplicação dos índices desenvolvidos para avaliar os modelos indicam que a guirlanda apresentou melhor resultado, destacando-se a baixa dificuldade de instalação do modelo no talude, a baixa dificuldade de preenchimento do solo-substrato/sementes no modelo e o alto desenvolvimento da adubação verde. O segundo melhor desempenho foi alcançado pelo modelo retentor seguido pelo modelo colmeia com o pior desempenho. Na análise dos bioindicadores ambientais do solo, a guirlanda apresentou melhor resultado na produção da matéria orgânica, em número de morfoespécies e em numero de indivíduos da fauna edáfica, seguindo pelos modelos retentor e colmeia. Os critérios preestabelecidos especificamente para avaliar esses modelos indicam potencial de aplicabilidade em futuros projetos de pesquisas para recuperar situações similares de degradação em áreas de mineração a céu aberto.
Mining represents an important sector in the economy promoting many economic and social benefits to the country. Although this represents positive impacts, the degradation scenarios originated by the mining activity cause negative impacts to the environment, which difficult the recovery of the degraded area. This research discusses the applicability of soil bioengineering as a promising strategy for recovering a slope of a waste dump. This slope consists of materials of different granulometries, high slope and high void ratio, physical characteristics that can hinder the development or even the recolonization of native vegetation by natural succession processes. Three soil bioengineering structural models, named as guirlanda, colmeia and retentor were made to retain a mix of soilsubstrate and seeds of Crotalaria juncea, Mucuna aterrina and Cajanus cajan as green manures for the production of organic matter and to promote the necessary conditions for future revegetation of the slope. The results obtained with application of the indices developed to assess the models indicate that guirlanda presented the best results, with highlights for the low difficulty in installing the model on the slope, the low difficulty of filling the model with the mix of soil-substrate and seeds and the high development of green manure. The second best performance was achieved by retentor model followed by the worst performing colmeia model. In the analysis of soil environmental bioindicators, guirlanda presented better results in the production of organic matter, in number of morphospecies and in number of individuals of the edaphic fauna, followed by the models retentor and colmeia. The specifically pre-established criteria to assess these models indicate the potential applicability in future research projects to recover similar situations of degradation in open pit mining areas.
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Klein, Patrícia Salvador Sanchez. "Avaliação das potencialidades das terras, adequação do uso das terras e indicadores de qualidade dos solos : subsídios para o planejamento conservacionista no perímetro irrigado de Mirorós (BA)." Universidade Federal de Sergipe, 2010. https://ri.ufs.br/handle/riufs/5432.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorThe practice of irrigated agriculture represents an increase of agricultural productivity, especially for areas with water deficit. Lands are frequently characterized erroneously which, coupled with lacking conservation measures, imposes serious consequences for the environment. In reality, any land use and intensive soil management when carried out unsustainably, can result in degradation processes. This study aims to provide subsidies for a conservationist planning in the Irrigated Perimeter of Mirorós, based on the rational use of land and adequate soil management. The perimeter is located in a semi-arid region of Bahia State (Brazil), municipality of Ibipeba, micro-region of Irecê. The following methods were adopted to evaluate the perimeter: evaluation of the edapho-climatic land potential, evaluation of the land potential for irrigation, determination of rates of land use adequacy as well as the use of indicators of soil quality for two kinds of land use (with and without irrigation). Thereby it was possible to define priority areas for intervention regarding land use and soil management (projected for conservation, recovery or recovery/preservation) and to identify the main susceptibilities for degradation processes or for improvements in soil quality, which have proven fundamental for conservationist planning strategies. The results showed that irrigated agriculture resulting in changes in the classification of land and greater impairment of soil quality, especially due to the susceptibility to the processes of compaction, salinisation and sodification, when compared to other uses without irrigation. On the other hand, the irrigated soils showed greater susceptibility to improvements in fertility and acidification. In fact, the negative effects as well as the improvements in soil quality were noted, in a smaller scale, in soils with other usage without irrigation. In general, the land of the perimeter in Mirorós possesses the potential for general agricultural use or for irrigated agriculture, but there is urgent need for interventions in soil management, including necessities of conservation or priority conservation. Additional interventions in usage are needed in areas that are being used in excess of their potential, resulting in the recovery/priority preservation of these areas. Furthermore, there are existing demands for interventions both in usage and management, resulting in areas that are priority for recovery. The proposed methods can be considered essential tools for the conservation of the natural resources in the study area, contributing towards sustainability in an agricultural environment.
A prática da agricultura irrigada representa um incremento da produtividade agrícola, principalmente para regiões com deficiência de água. No entanto, muitas vezes, a classificação das terras ocorre de forma incorreta, aliada à falta de medidas de conservação, o que tem imposto sérias conseqüências ambientais. Na realidade, qualquer uso da terra e manejo intensivo do solo, quando de maneira não sustentável, pode acarretar em processos de degradação. Este trabalho objetiva fornecer subsídios ao planejamento conservacionista, no Perímetro Irrigado de Mirorós, com base no uso racional das terras e manejo adequado do solo. Esse perímetro está localizado no semi-árido baiano, município de Ibipeba, microrregião de Irecê (BA). Para tanto, são adotadas a Avaliação do Potencial Edafoclimático das Terras e a Avaliação do Potencial das Terras para Irrigação, são determinadas as taxas de adequação do uso das terras, além da utilização de indicadores de qualidade do solo para dois tipos de usos das terras (com irrigação e sem irrigação). Com isso, houve possibilidade de definir áreas prioritárias de intervenção quanto ao uso das terras e manejo do solo (destinadas para Conservação, Recuperação ou Recuperação/Preservação) e identificar as principais suscetibilidades aos processos de degradação ou às melhorias na qualidade dos solos, as quais se mostraram fundamentais como estratégias para o planejamento conservacionista. Os resultados mostraram que a agricultura irrigada vem causando mudanças nas classificações das terras e maior comprometimento da qualidade do solo, sobretudo pela suscetibilidade aos processos de compactação, de salinização e de sodificação, em relação aos outros usos sem irrigação. Por outro lado, os solos irrigados se destacaram pela suscetibilidade às melhorias na fertilidade e na acidificação. Na verdade, os efeitos negativos, assim como melhorias na qualidade do solo, também foram notados nos solos com outros usos sem irrigação, porém de modo menos acentuado. Em geral, as terras do Perímetro de Mirorós possuem potencialidades para a agricultura geral ou para a agricultura irrigada, mas há urgência, especialmente, em intervenções no manejo, com necessidades de Conservação ou Conservação Prioritária. Além disso, há exigências de intervenções no uso, implicando na Recuperação/Preservação Prioritária de áreas que estejam sendo utilizadas acima do seu potencial, como também de intervenções no uso e manejo, ou seja, na Recuperação Prioritária. Os métodos propostos podem ser considerados ferramentas essenciais para a conservação dos recursos naturais na área de estudo e contribuir para o alcance da sustentabilidade no meio agrícola.
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Rodrigues, Paulo Sérgio Lobo. "Desenvolvimento e calibração de um protótipo de sensor de umidade do solo para aplicação em sistemas de irrigação." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2961.
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A importância da água na agricultura para o sucesso das lavouras é inquestionável. Nos tempos atuais, a irrigação tornou-se ferramenta estratégica para o sucesso das produções. Dentre outros benefícios, está a possibilidade de plantio de entre safras, o que possibilita melhorar o aproveitamento da área agrícola. Uma maior produtividade também pode ser alcançada por meio do uso artificial de condução de água às lavouras. No entanto, deve-se buscar o equilíbrio entre os interesses da produção com os critérios socioambientais. Outrossim, a disponibilização de água em excesso pode acarretar prejuízos, causando a proliferação de fungos e bactérias, e do possível apodrecimento das raízes. Desta forma, a irrigação de lavouras deve demandar controles eficientes do conteúdo de água no solo, primando pelo uso racional e ecologicamente sustentável dos recursos naturais envolvidos. É sabido que existem diversos sensores de umidade do solo que são capazes de obter o teor de água no solo, e que podem auxiliar no controle do uso da água. No entanto, os altos custos dos sensores de qualidade continuam sendo uma barreira para a implantação em lavouras de pequenos produtores, devido aos seus frágeis poderes aquisitivos. Motivado por isso, este trabalho buscou desenvolver um protótipo de sensor que possibilitasse a aferição da umidade do solo, sendo que a premissa principal seria o baixo custo. Para isso foi necessário realizar a calibração do protótipo, a partir de leituras simultâneas entre o mesmo e o equipamento de referência, o sensor profissional Watermark modelo 200SS-5. De forma acessória, o protótipo foi projetado para comunicar-se com plataformas externas, afim de possibilitar a integração e o monitoramento em tempo real. Os dados foram transmitidos para o banco de dados por intermédio da tecnologia wireless do microcontrolador ESP8266-12E (placa NodeMCU). Duas plataformas foram utilizadas, a ThingSpeak, bem como outra desenvolvida por este autor para o específico fim de integração com o protótipo. O custo para o desenvolvimento do protótipo correspondeu a 4,2% do valor correspondente ao sensor Watermark, possuindo características adicionais em comparação ao equipamento de referência, como a comunicação com meios externos e a fácil integração com sistemas de irrigação automatizada.The importance of water in agriculture for the success of crops is unquestionable. In the present times, irrigation has become a strategic tool for the success of productions. Among other benefits is the possibility of planting between harvests, which makes it possible to improve the utilization of the agricultural area. Higher productivity can also be achieved through the artificial use of water to the crops. However, a balance must be struck between the interests of production and the socio-environmental criteria. Also, the availability of water in excess can lead to damages, causing the proliferation of fungi and bacteria, and the possible rotting of the roots. In this way, irrigation of crops should demand efficient controls of soil water content, emphasizing the rational and ecologically sustainable use of the natural resources involved. It is known that there are several soil moisture sensors that are able to obtain the water content in the soil, and that can aid in the control of water use. However, the high costs of quality sensors continue to be a barrier to the implantation in crops of small producers, due to their fragile purchasing power. Motivated by this, this work sought to develop a prototype sensor that would allow the measurement of soil moisture, and the main premise would be the low cost. For this, it was necessary to carry out the calibration of the prototype, from simultaneous readings between the same and the reference equipment, the professional sensor Watermark model 200SS-5. Of accessory form, the prototype was designed to communicate with external platforms, possibiliting the integration and real-time monitoring. For the database the data were transmitted through the wireless technology of the ESP8266-12E microcontroller (NodeMCU board). Two platforms were used, the ThingSpeak, as well a another developed by this author for the specific purpose of integration with the prototype. The cost for the prototype development corresponded to 4.2% of the value corresponding to the Watermark sensor, having additional characteristics compared to the reference equipment, the such as communication with external means and the easy integration with automated irrigation systems.
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Araújo, édson Alves de. "Caracterização de solos e modificações provocadas pelo uso agrícola no assentamento Favo de Mel, na região do Purus Acre." Universidade Federal de Viçosa, 2000. http://locus.ufv.br/handle/123456789/5549.
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Previous issue date: 2000-12-14Actually in Acre the extensive pastures and the settlement projects (PA s) are responsible for most deforestation. The itinerant agriculture where the soil is used over a 2-year period prevails in PA s. Later on, the soil is left on fallow for recovering its fertility and/or to be incorporated to the extensive pasture. The use of the soil for a longer period and under a sustained way could be reached if appropriate management practices are adopted, so avoiding the deterioration of the soil as to its physical, chemistry and biological characteristics. From this premise it was objectified to characterize the soils and evaluate their physical and chemical alterations under different use types and so to supply subsidies to decision making on a more rational use. So, four locations inserted in the same soil conditions were selected (distrophic Yellow Argisols medium/clayish texture plane relief) at the Favo de Mel settlement on eastern Acre, in Purus region. The evaluated uses were: natural forest (control); natural newly-opened up forest submitted to intensive burning; planting of 2-years old pupunha (Bactris gassipae) and 4-years old brachiaria pasture (Brachiaria brizantha). Also, informal interviews were performed with farmers, and the root system were evaluated through digital images. It was concluded that the soil under pasture presented the highest density values, so suggesting a tendency to compaction. The nutrients and the organic carbon are found at low contents as well as concentrated in the first soil centimeters; and they tended to increase with intensity and time of soil use. The potassium drastically decreased in the pasture ecosystem, possibly due to losses by erosion and removal by pasture. The humina fraction prevailed on all four systems of soil use. Most vegetal biomass of the forest roots were concentrated down to 20-cm soil depth. There was also high correlation between the area and length of the roots. The farmers of Favo de Mel are coming from unsuccessful settlements, and the desistance index has been relatively low, so corroborating the importance of the environment on man's permanence in field.
Atualmente, no Acre, as pastagens extensivas e projetos de assentamento (PA) são responsáveis pela maior parte do desmatamento. Nos PA predomina a agricultura itinerante, onde o solo é utilizado por um período de dois anos. Posteriormente, é deixado em pousio para recuperação da fertilidade e, ou, incorporado à pastagem extensiva. O uso do solo por um período mais longo, e de forma mais sustentada, poderia ser alcançado se fossem adotadas práticas de manejo adequadas que evitassem a deterioração do solo quanto às suas características físicas, químicas e biológicas. A partir desta premissa, objetivou-se caracterizar os solos e avaliar suas alterações físicas e químicas, sob diferentes tipos de uso, e assim fornecer subsídios à tomada de decisão sobre um uso mais racional. Para tanto, selecionaram-se quatro locais inseridos nas mesmas condições de solo (Argissolo Amarelo distrófico, textura média/argilosa, relevo plano) no assentamento Favo de Mel, a leste do Acre, na região do Purus. Os usos avaliados foram: mata natural (testemunha); mata natural recém desbravada e submetida à queima intensiva; plantio de pupunha (Bactris gassipae) com dois anos e pastagem de braquiária (Brachiaria brizantha) com quatro anos. Também foram feitas entrevistas informais com os agricultores e o sistema radicular foi avaliado com imagens digitais. Conclui-se que o solo sob pastagem apresentou os maiores valores de densidade, o que sugere uma tendência à compactação. Os nutrientes e o carbono orgânico encontram-se em baixos teores, concentrados nos primeiros centímetros de solo, tendendo a aumentar com a intensidade e o tempo de uso do solo. O potássio decresceu, drasticamente, no ecossistema pastagem devido, possivelmente, às perdas por erosão e retirada pelo pastejo. A fração humina predominou nos quatro sistemas de uso do solo. As raízes da mata concentraram-se na maior parte de sua biomassa vegetal, nos primeiros 20 cm de profundidade do solo. Houve, também, alta correlação entre área e comprimento de raízes. Os agricultores do Favo de Mel são provenientes de assentamentos mal sucedidos, e o índice de desistência tem sido relativamente pequeno, o que comprova a importância do ambiente na permanência do homem no campo.
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Zalamena, Jovani. "Impacto do uso da terra nos atributos químicos e físicos de solos de rebordo do planalto - RS." Universidade Federal de Santa Maria, 2008. http://repositorio.ufsm.br/handle/1/5560.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorChanges in land use can take into soil chemical and physical quality degradation. In the hillside areas of the Rio Grande do Sul State (RS) land degradation vulnerability is elevated, due to the combination of a strong undulated to mountainous relief and shallow soils. The general purpose of this study was to evaluate the chemical and physical attributes of soils located in the Sul-riograndense Plateau Border under different land uses. Two representative sites of the Plateau Border, characterized by steep slope areas with prevalence of family farms, were selected (Silveira Martins county (SM) and São João do Polêsine county (SJ)), and also a transition area situated between the Plateau Border and the Medium Plateau (Júlio de Castilhos county (JC)). In SM soil samples were collected in areas of no-tillage (PD), tillage (PC), reforestation (RF) and native forest (MN). In SJ soil samples were collected under native forest (MN), secondary forest (MS), old cropping (LV), new cropping (LN) and abandoned cropping (LA) areas. In JC the samples were collected under native forest (MN), native prairie (CN) and no-tillage (PD) areas. Samples were collected from 0 to 10cm and from 10 to 20cm. Modifications were observed in soil chemical and physical attributes due to the different land uses when compared to the native forest. In systems that do not receive constant external additions, a decrease in soil chemical fertility was observed. Soil organic matter content decreased as the land use intensity increased. C-O-alquyl was the carbon group that presented the largest contribution in the spectra of 13C NMR, independent of the land use system. The main physical alterations observed were the decreases of soil macroporosity, total porosity and saturated hydraulic conductivity and the increase in soil density when compared to soil natural conditions. Soil aggregation parameters did not show to be good indexes to identify changes due to the land use in this study.
As mudanças na utilização das terras podem levar à degradação da qualidade química e física do solo. Nas áreas de encosta do estado do Rio Grande do Sul (RS) a vulnerabilidade à degradação das terras é elevada, devido a combinação de relevo forte ondulado a montanhoso e solos com pequena profundidade efetiva. O objetivo geral deste trabalho foi avaliar as características químicas e físicas do solo de áreas situadas no Rebordo do Planalto na região central do RS, sob diferentes usos da terra. Para isso foram selecionadas duas áreas representativas da região denominada Rebordo do Planalto, caracterizada por áreas de encosta com predomínio da agricultura familiar em pequena escala (Silveira Martins (SM) e São João do Polêsine (SJ)) e uma área de transição entre o Rebordo do Planalto e o Planalto Médio (Júlio de Castilhos (JC)). Em SM foram coletadas amostras de solo no sistema de plantio direto (PD), plantio convencional (PC), reflorestamento (RF) e mata nativa (MN). Em SJ foram coletadas amostras de solo sob os usos na mata nativa (MN), mata secundária (MS), lavoura velha (LV), lavoura nova (LN) e lavoura abandonada (LA). Em JC as amostras foram coletadas em áreas de mata nativa (MN), campo nativo (CN) e plantio direto (PD). As amostras foram coletadas na profundidade de 0-10 e 10-20 cm. Através dos resultados obtidos, observaram-se modificações nas características químicas e físicas do solo em função dos diferentes usos da terra, ao comparar com a mata nativa. Em sistemas que não recebem adições constantes de fontes externas, ocorreu uma depressão da fertilidade química. A matéria orgânica do solo teve diminuição nos teores, conforme aumentou a intensidade de uso da terra. O grupo C-O-alquil foi o grupo de carbono que apresentou a maior contribuição nos espectros de RMN 13C, independente do sistema de uso da terra. As principais alterações físicas ocorridas em comparação com as condições naturais do solo, foram diminuições da macroporosidade, porosidade total e condutividade hidráulica saturada e aumento na densidade do solo. Os parâmetros de agregação do solo, neste trabalho, não se mostraram como bons índices de avaliação para identificar mudanças em função dos diferentes usos da terra.
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Markussen, Michael. "Waldkonversion und Bodendegradation in Bergnebelwaldgebieten Guatemalas (Alta Verapaz)." Doctoral thesis, [S.l. : s.n.], 2003. http://hdl.handle.net/11858/00-1735-0000-0006-B318-B.
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(9842276), Kartik Venkatraman. "Phytocapping of municipal landfills: Evaluating the performance of 21 tree species and two soil depths." Thesis, 2013. https://figshare.com/articles/thesis/Phytocapping_of_municipal_landfills_Evaluating_the_performance_of_21_tree_species_and_two_soil_depths/13433012.
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"Capping is a mandatory landfill closure procedure to isolate the waste from outside environment, mainly rain water. Clay caps are mostly expensive and often fail to limit entry of water into the waste by developing cracks due to desiccation. To reduce capping costs and to increase environmental benefits, an alternate capping system called ‘Phytocapping’ was trialled at Lakes Creek Road Landfill, Rockhampton, Australia. This system consists of a soil cover and vegetation. Soil cover stores water during rainfall events and the vegetation removes the stored water via transpiration. Trees also act as ‘rain interceptors’ by trapping certain proportion of the rainfall in their canopy. Soil and plants also contribute to reduced methane emission by supporting methanotrophs in their root zone."
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(9839696), Mar Mar Thi. "Selection of tomato genotypes that hyperaccumulate cadmium, for use in phytoremediation of cadmium contaminated sites." Thesis, 2012. https://figshare.com/articles/thesis/Selection_of_tomato_genotypes_that_hyperaccumulate_cadmium_for_use_in_phytoremediation_of_cadmium_contaminated_sites/13465631.
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"Presence of high levels of Cd in soils results in accumulation of Cd in the food crops. Consumption of CD rich food items can induce cancer as well as causing health impacts in humans. Accumulation of Cd in the soils and plants can also cause other environmental impacts. One way to minimise these adverse impacts would be to remove Cd from contaminated soils by chemical or biological means.... Techniques such as phytoremediation may be used to remove Cd from contaminated soils economically.... The aim of this study was to select genotypes of tomato that would grow well in media containing high concentrations of Cd and accumulate high concentrations of Cd in their shoot tissues, so that they may be used in phytoremediation of Cd contaminated sites"--Abstract.
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Wall, Andrew James. "The effect of poplar stand density on hill country pastures : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy (PhD), Massey University, Palmerston North, New Zealand." 2006. http://hdl.handle.net/10179/1517.
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Page xvi is missing from both the electronic and print copyOne-third of the North Island of New Zealand has been identified as requiring increased soil conservation if pastoral farming is to be sustainable. For over 50 years the planting of widely spaced poplar trees (Populus spp.) has been one of the main methods used to control soil erosion on hill pastures. Research has shown that these plantings have successfully decreased soil erosion but their impact on the productivity of pastoral farming has received little research attention. The research that has been undertaken has found poplars can suppress understorey pasture production by up to 40%, suggesting that farmers require more research information on the impact of planting conservation trees on the productivity of their farm if the use of conservation trees is to be more widely adopted on erosion prone land. The objective of this thesis was to provide comprehensive data on the relationship between the range of poplar densities used for soil conservation on the light and soil under poplars, and consequently the effect on understorey pastures. Three field sites on commercial sheep and beef hill farms, in regions with contrasting summer soil moisture availability, Manawatu (one site) and Central Hawke's Bay (two sites), were monitored for two years. Tree stocking rates ranged from 0 to 375 trees/ha. Measurements were based on units of four trees with most measurements either directly below the tree crowns or in the gaps between the trees, but more intensive transect measurements were also made. Photosynthetically active radiation (PAR) and the ratio of red to far red light (R:FR) were measured under the trees and in open pasture controls. Stand density indices used included all the commonly used measures of tree canopies, including digital photography, and stem diameter at breast height (DBH). PAR transmission was inversely related to all of the stand density indices with canopy closure based on digital photographs being the most robust of the indices used. PAR under the trees, relative to open pasture, was greater in the gaps than below tree crowns. Under a completely closed canopy, PAR transmission was reduced to 15-20% and 50-55% of the open pasture in summer and winter, respectively. The RFR under the trees, relative to open pasture, decreased markedly at high stand densities (allowing less than 40% PAR transmission) in summer, but was similar in winter. The change in PAR under the trees was shown to be a major factor limiting pasture growth, particularly directly below the tree crowns. For both summer and winter, canopy closure measured with a standard digital camera was strongly related to stand level PAR transmission (r2=0.88-0.97; P<0.0001) and was also a practical method of measuring canopy closure in the field. The soil measurements confirmed earlier research that soil pH increases under mature poplar trees. There was a 0.2 - 0.7 unit increase in soil pH in the upper 75 mm of soil over both contrasting regions. The soil fertility under the trees in terms of requirements for pasture growth was similar to that of the open pasture with calcium and potassium up to 2.2 and 9.0 quick test units higher in the soil under the trees than in the open pasture, respectively. The direct cause of the increased concentration of some cations under the trees was the annual tree leaf litter. Overall, the soil fertility under the trees had the potential to produce similar pasture production to that of the open pasture with the added advantage of less acid conditions. Averaged over all sites the respective annual net herbage accumulation (ANHA) under poplar canopy closures of 25, 50 and 75 % was estimated from the equations developed to be 77, 60 and 48% of the open pasture. The greatest decrease was directly below the tree crowns where at canopy closures greater than 20% the ANHA was a relatively constant 50% of open pasture. In the vertically projected gap between trees the ANHA decreased by 6.6% relative to open pasture for each 10% increase in canopy closure. At approximately 80% canopy closure there was no difference between the ANHA directly below the trees and in the gap. Pasture net herbage accumulation (NHA) under the trees relative to open pasture was at its lowest in summer and autumn (36% of open pasture under a closed canopy), and at its greatest in early spring before tree canopy leafed out (72% of open pasture under a closed canopy). The botanical composition and feed value of the pasture under the trees was broadly similar to that of the open pasture. The greatest impact of the poplars on the pasture was decreased NHA due to shading. The decrease in NHA directly below mature unpruned poplars is substantial and would decrease farm profitability if the poplar stand density were high over a large area of the farm. The use of poplars for soil conservation is essential but these results show the importance of managing trees through pruning and thinning so that canopy closure is minimised. ANHA under the trees can be maintained at 75% of the open pasture if canopy closure is prevented from exceeding 30-40%.
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Langley, Gail. "Seed viability in topsoil stockpiles used for arid zone minesite rehabilitation in the Middleback Ranges of South Australia." 2002. http://arrow.unisa.edu.au:8081/1959.8/46671.
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The aim of this research is to assess various options for the management of topsoil stockpiles on disturbed lands and to evaluate the viability and germinability over time of the seedbanks in these stockpiles for use in rehabilitation. To predict their success, experimental trials were designed and conducted.
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Atkinson, Victoria. "Mine and industrial site revegetation in the semi-arid zone, North-Eastern Eyre Peninsula, South Australia." 2005. http://arrow.unisa.edu.au:8081/1959.8/46701.
Full textAbstract:
This research aims to develop the present knowledge of arid zone rehabilitation by scientifically testing topsoiling and seeding treatments on the Eyre Peninsula, South Australia, in a way that enables the widest application and comparison to other mining leases throughout the arid lands.
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Roskruge, Nick. "Hokia ki te whenua : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Soil Science at Massey University, Palmerston North, New Zealand." 2007. http://hdl.handle.net/10179/1725.
Full textAbstract:
This thesis aIms to produce a distinctive model for the sustainable horticultural development of Maori resources, primarily land. It is inclusive of tikanga Maori and indigenous production systems based on the unique body of knowledge aligned to Maori. The integration of this knowledge with western science is both argued and applied through the model itself. The hypothesis applied was that matauranga Maori relevant to horticulture and pedology can inform and add value to the future development of Maori land resources. The thesis is bui lt on a unique set of contributing knowledge bases aligned to soils and horticultural management supported by three case studies, identified through their common association i.e. whakapapa links. The format of the thesis intentionally follows science principles in structure and presentation and some assumptions are made regarding base knowledge surrounding Maori cultural factors and the science disciplines relative to soils and horticul ture. The indigenous element, including Maori knowledge, is incorporated into the model using a triadic kosmos/corpus/praxis approach. Where kosmos is applied as Te A o Miiori, corpus as miitauranga Miiori and praxis as tikanga Miiori, the relationship between each element is clear and the interpretation of the associated knowledge becomes more apparent and can be applied to cultural assessments of resources, i ncluding land. The crux of the cultural assessment model is the quality of information used to assess Maori resources, especially from the cultural perspective. The Maori cultural paradigm, traditional horticulture and pedology, and various decision systems are purposefully accessed to act as contributors to the assessment model and to highlight the diversity and quality of information land managers have at their disposal. The ability to apply a cultural layer drawn from a body of knowledge not previously included in decision models relative to land utility in New Zealand is the key point. of difference of the model. The model is discussed from the perspective of its beneficial role for future use by Maori and how it can be continuously refined to meet the needs of Maori land owners and thus contribute to the rangatiratanga of Maori.
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Prasad, Kamal Kishor. "Revegetation of recent soil slips in Manawatu : a thesis presented in partial fulfilment of the requirements for the degree of Master in Applied Science at Massey University." 2009. http://hdl.handle.net/10179/1435.
Full textAbstract:
Trifolium repens, Lotus pedunculatus and Holcus lanatus were oversown on two recent soil slip surfaces at AgResearch’s Ballantrae pastoral hill‐country farm near Woodville. The two slip surfaces were located on (Manamahu steepland soil) sedimentary mudstone. One slip had a north aspect and the other had a south aspect. Both slips were located on a land class 6 with slope 28‐330. The pasture species were oversown during early spring and the percentage seedling emergence and early establishment from viable seeds oversown was analysed at early spring (Day 15), late spring (Day 45), early summer (Day 90), and late summer (Day 120). The slip surfaces showed micro‐climatic extremes in terms of both soil moisture and surface temperatures during the summer period. Significant differences (P < 0.05) were found in soil moisture between north and south facing slip surfaces. Higher soil moisture and lower soil mean temperature were recorded on the south aspect slip surface. Significant differences (P < 0.05) were found between the three pasture species in terms of seedling emergence and early establishment. Significant differences (P < 0.05) were also found with aspect. The south aspect slip surface had a higher percentage of seedling emergence and earlier establishment for all the species. Interaction between species by aspect became significantly different (P < 0.05) at Day 90 and Day 120. The main effects of time and species were also significantly different (P < 0.05) illustrating seedling emergence and establishment as a race against time. Trifolium repens was a more successful pasture specie, than L. pedunculatus and H. lanatus due to its higher consistency on both north and south slip surfaces. Oversowing T. repens during early spring is a viable option for rehabilitation of recent soil slips in Manawatu.
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Bangamwabo, Victor Mugabo. "Spatial and temporal extent of land degradation in a communal landscape of KwaZulu-Natal, South Africa /." 2009. http://hdl.handle.net/10413/676.
Full text
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"Land degradation and rehabilitation in severely eroded granitic area of south China: a case study of Deqing." Chinese University of Hong Kong, 1991. http://library.cuhk.edu.hk/record=b5886894.
Full textAbstract:
by Choi Chi Hoi.Thesis (M.Phil.)--Chinese University of Hong Kong, 1991.
Bibliography: leaves 171-178.
ABSTRACT --- p.iii
ACKNOWLEDGMENTS --- p.v
TABLE OF CONTENT --- p.vi
LIST OF FIGURES --- p.x
LIST OF TABLES --- p.xii
LIST OF PHOTOS --- p.xiv
LIST OF APPENDICES --- p.xvi
Chapter I --- INTRODUCTION
Chapter 1.1 --- Background --- p.1
Chapter 1.2 --- Objectives --- p.6
Chapter 1.3 --- Uniqueness and Significance of the Study --- p.7
Chapter 1.4 --- Some Key Concepts --- p.9
Chapter 1.5 --- Organization of the Thesis --- p.11
Chapter II --- THE STUDY AREA
Chapter 2.1 --- Selection of the Study Area --- p.12
Chapter 2.2 --- The Physical and Socio-Economic Environment of the Deqing County --- p.17
Chapter 2.2.1 --- Location --- p.17
Chapter 2.2.2 --- Climate --- p.17
Chapter 2.2.3 --- Geology and Landform --- p.18
Chapter 2.2.4 --- Vegetation --- p.18
Chapter 2.2.5 --- Population and Economic Activities --- p.19
Chapter 2.2.6 --- History of Soil Erosion and Conservation --- p.21
Chapter 2.3 --- The Shenchong Basin --- p.26
Chapter 2.4 --- The Lichong Basin --- p.28
Chapter 2.5 --- The Resource Base of Deqing --- p.30
Chapter III --- METHODOLOGY --- p.34
Chapter 3.1 --- Conceptual Considerations --- p.34
Chapter 3.2 --- Land Degradation Processes --- p.35
Chapter 3.2.1 --- Nutrient Loss from Hillslopes --- p.38
Chapter 3.2.2 --- Iron Toxicity --- p.43
Chapter 3.2.3 --- Properties and Nutrient Status of Rehabilitated Soils --- p.44
Chapter 3.2.4 --- Methods of Chemical Analysis of Water and Soil Samples --- p.49
Chapter 3.3 --- Cost-Benefit Analysis of Rehabilitation Measures --- p.50
Chapter 3.4 --- Problems and Limitations --- p.54
Chapter IV --- LAND DEGRADATION： PROCESSES AND PROBLEMS --- p.56
Chapter 4.1 --- Landscape Changes in a Severely Eroded Granitic Area --- p.56
Chapter 4.2 --- Land Degradation Processes 一 On-site Effects --- p.60
Chapter 4.2.1 --- Soil Loss on the Hillsides --- p.60
Chapter 4.2.2 --- Loss of productivity on the Hillsides --- p.64
Chapter 4.3 --- Land Degradation Process - Off-Site Effects --- p.70
Chapter 4.3.1 --- Burial of Agricultural Land Beneath Alluvial Fans --- p.70
Chapter 4.3.2 --- Concentration of Dissolved Iron in Sub-surface Water --- p.74
Chapter 4.4 --- Concluding Remarks --- p.78
Chapter V --- COST-EFFECTIVENESS OF EROSION CONTROL MEASURES THEORETICAL CONSIDERATIONS --- p.80
Chapter 5.1 --- Introduction --- p.80
Chapter 5.2 --- Economic-Biophysical Management Linkages in the Shenchong Basin --- p.80
Chapter 5.3 --- Range of Erosion Control/Land Use Options --- p.83
Chapter 5.4 --- Methodology --- p.83
Chapter 5.4.1 --- Data Sources --- p.85
Chapter 5.4.2 --- Economic Valuation Techniques --- p.85
Chapter 5.5 --- Cost-Effectiveness Evaluation of Erosion- Control Measures --- p.87
Chapter 5.5.1 --- Option 1 - Hillsides are Maintained Under Dense Fern and Tree Cover and No Use is Permitted --- p.88
Chapter 5.5.2 --- Option 2 : Slope - Maintaining Dense Vegetation Cover but Permitting Sustained Yield Harvesting of Fern for Fuel and Resin and Timber Production --- p.90
Chapter 5.5.3 --- Option 3 : Slope - Building Terraces on Hillslopes --- p.92
Chapter 5.5.4 --- Option 4 : Slope - No Erosion Control Measures --- p.94
Chapter 5.5.5 --- Option 5 : Slope - Conversion from Fern and Woodland to Baji and Yu Gui Crops --- p.94
Chapter 5.5.6 --- Option 6 - Small Check Dams Constructed to Control Gully Erosion --- p.94
Chapter 5.5.7 --- Option 7 : Gully - Large Check Dams --- p.97
Chapter 5.5.8 --- Option 8 : Gully - Biological Dams --- p.98
Chapter 5.5.9 --- Option 9 : Gully - Infilling of Gullies --- p.99
Chapter 5.5.10 --- Option 10 : gully - No Erosion Control --- p.100
Chapter 5.6 --- Policy Implications --- p.100
Chapter 5.7 --- Policy Optimization With Multiple-Objective Decision Modeling --- p.102
Chapter VI --- REHABILITATION PROGRAM AT SHENCHONG AND LICHONG RECONSIDERED --- p.107
Chapter 6.1 --- Introduction --- p.107
Chapter 6.2 --- Land Rehabilitation at Shenchong --- p.107
Chapter 6.3 --- Land Rehabilitation at Lichong --- p.111
Chapter 6.4 --- Ecological Considerations --- p.119
Chapter 6.5 --- Agricultural Considerations --- p.124
Chapter 6.5.1 --- Chemical Soil Properties --- p.126
Chapter 6.5.2 --- Physical Soil Property --- p.135
Chapter 6.6 --- Economic Considerations --- p.143
Chapter 6.6.1 --- Costs and Benefits of Rehabilitation Activities --- p.144
Chapter 6.6.2 --- Sustainability of the Rehabilitation Programs --- p.146
Chapter 6.6.3 --- Distribution of Costs and Benefits over Time --- p.148
Chapter 6.7 --- Institutional Considerations --- p.151
Chapter 6.7.1 --- Rural Economic Reform --- p.152
Chapter 6.7.2 --- Institution Set-up of the Two Brigades --- p.153
Chapter 6.7.3 --- Distribution of Cost and Benefits --- p.154
Chapter 6.7.4 --- Risk Management --- p.155
Chapter 6.7.5 --- Land Use Planning --- p.156
Chapter 6.7.6 --- Motivation --- p.157
Chapter 6.7.7 --- The Search for Solution --- p.159
Chapter VII --- CONCLUSION --- p.162
Chapter 7.1 --- Introduction --- p.162
Chapter 7.2 --- Discussion --- p.166
BIBLIOGRAPHY --- p.171
APPENDICES --- p.179
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Wang, Pei-Ling. "Modeling global human-induced soil degradation and its impacts on water balance." Thesis, 2021. http://hdl.handle.net/1828/13361.
Full textAbstract:
Soils are a critical resource for supporting ecosystems, agricultural systems, and human wellbeing. However, these same soils have been degraded by human activities throughout human history. Despite the rapid development of global models that include dynamic changes in land use and land cover (LULC) and biogeochemical processes to assess climate and hydrological impacts, soil properties are often assumed to be spatially or temporally constant. These assumptions can affect the results of model projections, impact assessments and underestimate the human impact on Earth systems. This study reveals the physical impacts of human-altered soil conditions on the global water balance through a meta-analysis study and soil degradation modeling. We link major global LULCs to four hydrologic soil groups: sandy (sand, sandy loam, and loamy sand), loamy (loam, silty loam, and silt)), clayey soils (clay, sandy clay, clay loam, silty clay, and silty clay loam), and sandy clay loam) from 850 to 2015 AD, and identified loamy and clayey soils as the preferred soils for most human land uses. Humans selectively use those soils for intensive agriculture and pasture activities, while grazing occurs on sandier soils.
To simulate the impact of human activities on soils, several soil change models were built for soil organic carbon (SOC) content, soil texture (sand, silt, and clay), and soil bulk density from meta-analyses of site observations. The models were applied globally based on the LULC and soil relations, global environmental and soil conditions, and LULC distributions. Pedotransfer functions were applied to estimate soil water-holding capacity using those soil properties, then a Thornthwaite-type water balance model was used to assess the impacts of soil degradation on the global water balance. Results show that under a high-intensity LULC scenario (conventional tillage on croplands and heavy grazing), SOC decreases by 363 Pg and water deficit increases 78 km3 globally. The impacts on SOC and deficit are reduced to 213 Pg and 51 km3, respectively, when reducing land-use intensity by substituting animal ploughing/no-till and light grazing for conventional tillage and heavy grazing. Impacts from other LULC types are identical for these two LULC scenarios. Development of this history between LULC and soil properties allows for improved simulation of human impacts on global water, energy, and biogeochemical cycles. The results of the water balance simulations demonstrate how different soils representations in models can significantly alter the estimates of global evapotranspiration, water deficit, and surplus. This study contributes to developing a better understanding of the processes by which human-induced soil degradation impacts climate/hydrological models and providing a mechanism to better assess the impacts of humans on the Earth system. The outcome will also complement numerous ongoing global studies that evaluate the impacts of climate change on water resources and society.Graduate
2022-08-09
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Mkhosi, Ntombi Elizabeth. "The evaluation of the state of grass species composition in some degraded tribal areas in the Zeerust district / Ntombi Elizabeth Mkhosi." Thesis, 2003. http://hdl.handle.net/10394/11396.
Full textAbstract:
The evaluation of the state of grass species composition was conducted as an attempt to
confirm the survey conducted by the United Nations Convention to Combat
Desertification (UNCCD), where the Zeerust District was identified as an area with
serious degradation problems. Quantitative data was obtained through botanical surveys
(April 2001-February 2002) and verified by household surveys (March 2001-April 2002).
Study sites included Braklaagte, Dinokana, Doomlaagte, Serake and Supingstad, with
benchmark sites in Madikwe Grune Reserve. Between 6-12 survey points per site were
selected after consultation with local Agricultural Extension Officers and communities.
Survey points included the range of veld condition between bush encroached and severely
denuded and eroded areas. The results indicate 12.3 % to 45.1 % loss of vegetal cover.
Resistance above 2 000 ohms, base saturation exceeding 100 % and pH values below 5.5
are evidence of soil degradation. The general profile of the fanning household is that of an aging adult community, with however, a relatively good knowledge of fanning practices. 52 % of the respondents depend on the government pension fund as a source of income. 60 % of the respondents use crop fanning products strictly for household purposes. Poor economic return from fanning activities has resulted in overutilization of the herbaceous layer with consequent changes of grass species composition towards retrogression and the establishment of woody species. This environmental degradation is a serious risk to long-term sustainable development. It is therefore, recommended that environmental education programmes and ecological restoration projects be started in degraded areas. The government should set up and enforce land-use policies. Community participation should be encouraged in all land care activities. Land degradation is a real social problem that must be tackled before many people's aspirations of a better life are met.Thesis (M.Sc. (Biology) North-West University, Mafikeng Campus, 2003