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Articoli di riviste sul tema "Soils Calcium content"
1
Cichota, R., I. Vogeler, N. S. Bolan e B. E. Clothier. "Cation influence on sulfate leaching in allophanic soils". Soil Research 45, n. 1 (2007): 49. http://dx.doi.org/10.1071/sr06070.
Testo completoAbstract (sommario):
We have examined the influence of the ionic composition of the soil solution on the movement of sulfate and calcium in 2 New Zealand soils with differing allophane content. For this study, we have carried out a series of miscible displacement experiments using repacked and intact soil columns, in which sulfate was applied in the presence of either calcium or potassium as the accompanying cation. Our results showed that sulfate leaching was significantly retarded in the soil with higher allophane content when applied with calcium. On the other hand, no effects were observed for all studied soils when potassium was used as the accompanying cation. In addition, in soils with high allophane content, calcium also had its retention increased when sulfate was present. The increase in sulfate adsorption was accompanied by corresponding increase in calcium adsorption. These findings evidenced the presence of co-adsorption, or ion-pair adsorption (IPA), in allophane-containing soils. The extent of this adsorption is dependent on the soil pH, the accompanying cation, and the allophane content of the soil.
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Rogóż, Antoni, e Monika Tabak. "Contents of selected macroelements in soils, potatoes and fodder beets at variable soil reaction / Zawartość wybranych makroelementów w glebach oraz w ziemniakach i burakach pastewnych przy zmiennym odczynie gleby". Soil Science Annual 66, n. 1 (1 marzo 2015): 3–9. http://dx.doi.org/10.1515/ssa-2015-0012.
Testo completoAbstract (sommario):
Abstract The aim of the research was to determine the concentration of selected macroelements in soil and in root crops (potatoes and fodder beets) at a variable soil reaction. The changes in pH values in the studied soils influenced the content of these elements in soluble forms determined in 0.1 mol HCl·dm-3. A statistical analysis showed a positive relationship between the soil pH value and the calcium and magnesium contents in a form close to the total form, as well as the content of soluble forms of phosphorus, calcium, and magnesium. The content of the studied macroelements, i.e. phosphorus, calcium, magnesium in the cultivated fodder beets and potatoes depended on abundance and form in which the studied elements occurred in soil, and also on specie and analyzed part of the plant. Along with the increase in pH values of the an increase in the phosphorus content and reduction of the magnesium content in the roots and above-ground parts of the beets were found. The calcium content in the roots increased along with an increase in pH of the soils, whereas direction of changes in the content of this element in the petioles and laminae of the beets was not unambiguous. A slight decrease in the content of the studied elements in the potato tubers (along with the increase in pH of the soils) was found.
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Yildiz, Ercan, Mehmet Yaman e Ahmet Sümbül. "RELATIONSHIPS BETWEEN PHYSICAL AND CHEMICAL PROPERTIES OF SOILS AND PLANT NUTRIENT CONTENT OF LEAVES IN THE APPLE ORCHARDS". Current Trends in Natural Sciences 11, n. 21 (31 luglio 2022): 139–44. http://dx.doi.org/10.47068/ctns.2022.v11i21.016.
Testo completoAbstract (sommario):
This study was carried out in 42 orchards located in the lowland of Develi, where the apple cultivation is intense in Kayseri province. The analyses were made to determine pH, CaCO3, EC, organic matter, available phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), zinc (Zn), manganese (Mn) and copper (Cu) in soil samples and nitrogen (N), P, K, Ca, Mg, Fe, Zn, Mn, Cu, and boron (B) in leaf samples. In the study, the relationships between some physical and chemical properties of the soils and the plant nutrient content of the leaves were evaluated by correlation analysis. In the study, between some physical and chemical properties of soils and the nutritional elements of soils and leaves were found important statistical relations. These relationships were mostly between soil samples rather than leaves. On the other hand, the pH and EC values of the soils showed less significant relationships with the nutrient contents of the samples according to the organic matter and CaCO3 contents of soils. It was determined that the organic matter content of the soils had a positive relationship with all the investigated elements except phosphorus. It has been determined that the relationship between the CaCO3 content and nutritional elements in the soils is statistically significant, it has a positive correlation with potassium and calcium and a negative correlation with other investigated elements. No significant relationships were found between the nutrient contents of the soils and the macro element contents of the leaves. While some important statistical relationships were determined between nutrient contents of the soils and micro element contents of the leaves, the highest correlation was determined between copper and boron contents. It was determined that the copper content of the leaves was positively related to the phosphorus, potassium and magnesium content of the soils and negatively related to the manganese content of the soils.
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PEKCAN, Tülin, Bihter ÇOLAK ESETLİLİ, Hatice Sevim TURAN e Erol AYDOĞDU. "Determination of Nutritional Status of Northwest Anatolia (North Aegean) Olive Growing Areas". MAS Journal Of Applied Sciences 7, n. 11 (10 marzo 2022): 210–20. http://dx.doi.org/10.52520/masjaps.221.
Testo completoAbstract (sommario):
The study was carried out to determine the productivity of olive plantations in 8 different districts of The North Aegean Region. For this purpose, soil and leaf samples were taken simultaneously from 26 different olive groves. 69.23% of the investigated surface soils (0-30 cm) are sandy loam, and 57.69% of the subsurface soils (30-60 cm) are sandy loam. It was determined that more than 50% of the soils were slightly alkaline and the lime contents were low at both depths. It is seen that the organic matter contents of 11% of the surface soils and 8% of the subsurface soils are low. Nitrogen contents at both depths are in the low class 38.46%. The available phosphorus contents of 23.08% of the surface soils and 11.54% of the subsurface soils are sufficient. Available potassium and calcium contents in all surface soils are sufficient. It was determined that the potassium content in 34.61% of the subsurface soils and the calcium content in 53.84% of the subsurface soils were sufficient and very high. It was determined that the available Mg content in 61.54% of the surface soil and 57.69% of the subsurface soil, was sufficient and very high. Sodium contents were determined adequately at both depths. When the leaf macro and secondary elements were examined according to the sufficiency limit values 46.15% of N, 26.92% of Ca 3.8% of Mg, and all the P and K contents, were found to be sufficient. of the microelements, 42.31% of B, 76.92% of Fe, 46.15% of Mn and 38.46% of Zn are sufficient. Considering the results of the study, it is recommended to make fertilizer recommendation based on the results of soil and leaf analysis in parallel with the regular cultural practices in order to obtain quality and high yield in North Aegean sustainable olive cultivation.
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Al-Tarbouli, Nameer Hamed Yassin. "Adsorption and physicochemical release of iron ions in soils with different content of Calcium Carbonate and Calcium Sulfate". Tikrit journal for agricultural sciences 22, n. 3 (30 settembre 2022): 137–47. http://dx.doi.org/10.25130/tjas.22.3.16.
Testo completoAbstract (sommario):
Three soils of different content of gypsum and lime were selected, the first soil (G1) and the second soil (G3), were obtained near the fields of the Faculty of Agriculture, Tikrit University. As for the third soil (G5), was taken from the AL- alam Village side east of Tikrit city to a depth of (0-10)cm. the proportions of gypsum were 5%, 15%, 25%, and the proportions of lime were 25%, 20%, and 10% for soils G1, G3, and G5, respectively. Ferrous sulfate was added as a source of iron ions added to the three soils in the following proportions (0,10,25,50,100,150,250,500,750) mg.L-1 The concepts of isotherm were tested by using the physicochemical Freundlich and Langmuir adsorption equations. The results of the study showed the success of both equations in describing of iron ion adsorption process for all three soils, because They achieve a high (R2) but Langmuir's equation showed a greater superiority due to its decreasing (SE). As it appears from the results of the study, the superiority of treatment (G1) over treatments (G3) and (G5) in the maximum adsorption values, binding energy, (PBCFe)(KG) and (Kd) for adsorption and release. As for the values of Labale iron, the lowest value was in treatment (G1)then it began to increase until it reached its value in treatment (G5). The (Δf) values for the three soils were positive, and that the highest value was in soil (G1), and starts declining to reach its value for soil (G5).
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Han, Guilin, Anton Eisenhauer, Jie Zeng e Man Liu. "Calcium Biogeochemical Cycle in a Typical Karst Forest: Evidence from Calcium Isotope Compositions". Forests 12, n. 6 (25 maggio 2021): 666. http://dx.doi.org/10.3390/f12060666.
Testo completoAbstract (sommario):
In order to better constrain calcium cycling in natural soil and in soil used for agriculture, we present the δ44/40Ca values measured in rainwater, groundwater, plants, soil, and bedrock samples from a representative karst forest in SW China. The δ44/40Ca values are found to differ by ≈3.0‰ in the karst forest ecosystem. The Ca isotope compositions and Ca contents of groundwater, rainwater, and bedrock suggest that the Ca of groundwater primarily originates from rainwater and bedrock. The δ44/40Ca values of plants are lower than that of soils, indicating the preferential uptake of light Ca isotopes by plants. The distribution of δ44/40Ca values in the soil profiles (increasing with soil depth) suggests that the recycling of crop-litter abundant with lighter Ca isotope has potential effects on soil Ca isotope composition. The soil Mg/Ca content ratio probably reflects the preferential plant uptake of Ca over Mg and the difference in soil maturity. Light Ca isotopes are more abundant in mature soils than nutrient-depleted soils. The relative abundance in the light Ca isotope (40Ca) is in the following order: farmland > burnt grassland > forests > grassland > shrubland. Our results further indicate that biological fractionation in a soil–plant system is a vital factor for Ca–geochemical transformations in soil surface systems.
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Loveland, P. J., J. Hazelden e R. G. Sturdy. "Chemical properties of salt-affected soils in north Kent and their relationship to soil instability". Journal of Agricultural Science 109, n. 1 (agosto 1987): 1–6. http://dx.doi.org/10.1017/s0021859600080904.
Testo completoAbstract (sommario):
SummarySoil instability, as measured by the dispersion ratios of the reclaimed salt-marsh soils of ca. 70 km2 of north Kent, was assessed on samples taken from 0–15, 35–50 and 70–85 cm depths from sites at the intersects of a 250 m square grid or along transects. The dispersion ratios were related to other soil properties including exchangeable sodium, potassium and magnesium percentages, organic carbon content, calcium carbonate content and electrical conductivity. The dispersion ratio correlates most closely with exchangeable sodium percentage and organic carbon content; weaker correlations exist with exchangeable potassium and calcium carbonate contents. Dispersion ratios rise sharply, i.e. reflect a marked increase in soil instability, when organic carbon content is less than 2·5% and calcium carbonate content is less than 2%. Magnesium has little effect on the dispersion ratio. The soil solution salt concentration (as expressed by electrical conductivity) is too low over much of the area to promote flocculation, and hence stability, of the soil clays.
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Neff, J. C., J. W. Harden e G. Gleixner. "Fire effects on soil organic matter content, composition, and nutrients in boreal interior Alaska". Canadian Journal of Forest Research 35, n. 9 (1 settembre 2005): 2178–87. http://dx.doi.org/10.1139/x05-154.
Testo completoAbstract (sommario):
Boreal ecosystems contain a substantial fraction of the earth's soil carbon stores and are prone to frequent and severe wildfires. In this study, we examine changes in element and organic matter stocks due to a 1999 wildfire in Alaska. One year after the wildfire, burned soils contained between 1071 and 1420 g/m2 less carbon than unburned soils. Burned soils had lower nitrogen than unburned soils, higher calcium, and nearly unchanged potassium, magnesium, and phosphorus stocks. Burned surface soils tended to have higher concentrations of noncombustible elements such as calcium, potassium, magnesium, and phosphorus compared with unburned soils. Combustion losses of carbon were mostly limited to surface dead moss and fibric horizons, with no change in the underlying mineral horizons. Burning caused significant changes in soil organic matter structure, with a 12% higher ratio of carbon to combustible organic matter in surface burned horizons compared with unburned horizons. Pyrolysis gas chromatography mass spectroscopy also shows preferential volatilization of polysaccharide-derived organic matter and enrichment of lignin- and lipid-derived compounds in surface soils. The chemistry of deeper soil layers in burned and unburned sites was similar, suggesting that immediate fire impacts were restricted to the surface soil horizon.
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Elisa, A. A., S. Ninomiya, J. Shamshuddin e I. Roslan. "Alleviating aluminium toxicity on an acid sulphate soils in Peninsular Malaysia with application of calcium silicate". Solid Earth Discussions 7, n. 4 (19 ottobre 2015): 2903–26. http://dx.doi.org/10.5194/sed-7-2903-2015.
Testo completoAbstract (sommario):
Abstract. A study was conducted to alleviate Al toxicity of an acid sulphate soils collected from paddy cultivation area in Kedah, Peninsular Malaysia. For this purpose, the collected acid sulphate soils were treated with calcium silicate. The treated soils were incubated for 120 days in submerged condition in a glasshouse. Subsamples were collected every 30 days throughout the incubation period. Soil pH and exchangeable Al showed positive effect; soil pH increased from 2.9 to 3.5, meanwhile exchangeable Al was reduced from 4.26 to 0.82 cmolc kg−1, which was well below the critical Al toxicity level for rice growth of 2 cmolc kg−1. It was noted that the dissolution of calcium silicate (CaSiO3) supplied substantial amount of Ca2+ and H4SiO42− ions into the soil, noted with increment in Si (silicate) content from 21.21 to 40 mg kg−1 at day 30 and reduction of exchangeable Al at day 90 from 4.26 to below 2 cmolc kg−1. During the first 60 days of incubation, Si content was positively correlated with soil pH, while the exchangeable Al was negatively correlated with Si content. It is believed that the silicate anions released by calcium silicate were active in neutralizing H+ ions that governs the high acidity (pH 2.90) of the acid sulphate soils. This scenario shows positive effect of calcium silicate to reduce soil acidity, therefore creates a favourable soil condition for good rice growth during its vegetative phase (30 days). Thus, application of calcium silicate to alleviate Al toxicity of acid sulphate soils for rice cultivation is a good soil amendment.
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Zhong, Yuqing, Guanghua Cai, Shiquan Wang, Huajin Qin, Caihong Zhang e Jiangshan Li. "Influence of Organic Content on the Mechanical Properties of Organic-Rich Soils Stabilized with CaO-GGBS Binder and PC". Water 14, n. 19 (28 settembre 2022): 3053. http://dx.doi.org/10.3390/w14193053.
Testo completoAbstract (sommario):
Organic-rich soil is a typical special soil often encountered in foundation treatment. Previous research has revealed that Portland cement (PC) not only pollutes the environment but is significantly affected by organic matter during its hydration and cementation. Although quicklime (CaO)-GGBS binder (CG) is an effective alternative to PC, its efficiency in treating organic-rich soils has not been studied. In this study, organic-rich soil was treated with two binders of CG and PC. The physical, mechanical, and chemical characteristics of the stabilized soils were tested at various organic contents, binder contents, and curing ages. The results show that the cracks in two treated soils increase with the increase in organic content and the reduction in binder content. CG-treated soils are more likely to shed big lumps after damage than PC-treated soils. The unconfined compressive strength (qu) and deformation modulus (E50) of stabilized soils increase with the increasing curing age and binder content but the decreasing organic content. The E50 of PC-treated soil is about 22~73 times qu, and the E50 of CG-treated soil shows an excellent linear relationship with qu. The moisture content of two treated soils increases as the organic content grows, but it falls as the curing age and binder content increase. The soil pH rises with the increasing organic content and binder content, but it declines with increased curing age. The strength development of organic-rich soils treated by the CG binder has an evident attenuation with the organic content. Given its possible environmental benefit, alkali (especially low calcium)-activated binder is appropriate for practical engineering with modest strength needs.
Tesi sul tema "Soils Calcium content"
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Baldock, Jeffrey Alexander. "Influence of calcium on the decomposition of organic materials in soils /". Title page, contents and introduction only, 1989. http://web4.library.adelaide.edu.au/theses/09PH/09phb178.pdf.
Testo completo
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Ali, Abdul-Mehdi Saleh. "Reactions of urea phosphate in calcareous and alkaline soils: Ammonia volatilization and effects on soil sodium and salinity". Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184694.
Testo completoAbstract (sommario):
Nitrogen (N) loss in the form of volatilized ammonia (NH₃) is a considerable problem when ammonium (NH₄⁺) forming fertilizers are applied to calcareous or alkaline soils. Large areas of agricultural land, contain alkalinity and salinity problems, are potentially suitable for crop production with little alteration. This study was conducted to determine and compare the effectiveness of urea phosphate (UP) in reducing soil alkalinity and NH₃ loss. The volatilization of NH₃ from UP and urea (U) was studied on 3 selected soils (Hayhook SL, Laveen L and Latene L) using an aeration system. Urea phosphate and U were each applied at rates of 0, 50, 100 and 200 ppm-N either to the surface dry or in solution or mixed with the soil. The volatilized NH₃ was trapped in sulfuric acid, sampled periodically and analyzed for N using the semi microkjeldahl distillation apparatus. The effect of UP, Sulfur-Foam (SF), Phosphuric Solution (PHP) and a mixture of SF and UP (Mix) on leaching soil sodium (Na) and salinity was also studies on two soils (Pima L and Crot CL) in columns. Each of these amendments was applied at a rate of one and two equivalent amounts of the exchangeable Naₑₓ. The highest N loss in the form of NH₃ occurred when U was applied to Hayhook soil. However, UP applied to Hayhook soil (neutral to acidic, coarse textured and low CaCO₃ content) resulted in the lowest NH₃-N loss. Less NH₃-N loss was found from U application to Laveen and Latene soils (fine textured with higher CaCO₃ content) than with Hayhook soil. The general trend was higher N loss, in the form of volatilized NH₃, with surface application dry or in solution than when mixed with the soil. This trend showed an increase in the amount of volatilized NH₃ with increasing rate of N application. Urea phosphate was as effective as PHP or Mix (acid containing fertilizers) treatments in reducing soil salinity and alkalinity in Pima and Crot soils. No difference was found between rates of application (1 and 2 equivalent amount of Naₑₓ) except for soil pH. A similar trend in the decrease in soil salinity was found to that of the pH which was in the order PHP, UP, Mix, SF and control treatments. No significant difference was found between SF and control treatments in all parameters. No significant difference was found between treatments for exchangeable Ca. This was affected by the Ca compounds present in the soil. Generally, UP is a potential fertilizer for supplying N and phosphorus (P) as plant nutrients, reducing NH₃ volatilization, and can be used as a soil amendment to control soil salinity and alkalinity.
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Suriadi, Ahmad. "Structural stability and Na-Ca exchange selectivity of soils under sugarcane trash management". Title page, Contents and Abstract only, 2001. http://web4.library.adelaide.edu.au/theses/09ASOM/09asoms961.pdf.
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Muhammed, Rawaz Dlawar. "Etude en chambre d'étalonnage du frottement sol-pieu sous grands nombres de cycles. Application au calcul des fondations profondes dans les sols fins saturés". Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066603/document.
Testo completoAbstract (sommario):
Ce travail de thèse porte sur l’étude du comportement de l’interface sol-pieu sous sollicitations cycliques dans les sols fins. Dans ce cadre, un important programme expérimental a été réalisé en chambre d’étalonnage, à partir d’une sonde-pieu et d’un piézocône testés dans des massifs d’argile saturée. Pour réaliser cette étude, on a, en particulier, développé un consolidomètre prototype pour la reconstitution des massifs d’argile. On s’est intéressé plus particulièrement, lors de chargements cycliques réalisés à déplacement contrôlé, aux évolutions du frottement local mobilisé à l’interface sol-pieu et de la résistance en pointe. L’étude expérimentale a permis de mettre en évidence l’influence des paramètres clés sur le comportement observé et, plus spécifiquement, sur l’évolution des propriétés de frottement d’interface. On s’est intéressé, en particulier, à l’influence de l’amplitude du chargement cyclique, de la fréquence des sollicitations, ainsi que du nombre de cycles appliqués. L’accent a été mis sur le cas des grands nombres de cycles, typiquement quelques centaines de milliers, encore peu étudié dans la littérature. Il faut également ajouter l’étude de l’influence du niveau des contraintes initiales appliquées au massif. Les résultats expérimentaux ont permis de mettre en évidence, après une phase de dégradation initiale, une phase de renforcement du frottement local. Ce type de comportement n’a pas encore été décrit dans la littérature. La phase de dégradation est attribuée à l’augmentation progressive de la surpression interstitielle à l’interface au cours des cycles, tandis que la phase de renforcement est attribuée à la dissipation progressive de la surpression interstitielle. Par ailleurs, un essai de chargement cyclique sur un piézocône a été réalisé afin de quantifier précisément la variation des surpressions interstitielles à l’interface sol-pieu et dans le massif, lors des différentes phases de chargement, et ainsi valider les interprétations faites concernant les phases de dégradation et de renforcementThis Ph.D. dissertation focuses on the behavior of the pile-soil interface under cyclic loading. In this context, an experimental program was conducted on the Navier calibration chamber using an instrumented pile-probe and a piezocone installed in saturated clay samples. In order to carry out this study, we developed, In particular a slurry consolidomètre prototype to reconstitute fully saturated clay samples. Special attention was given, during displacement controlled cyclic tests, to local friction evolution mobilized at the pile-soil interface and mobilized tip résistance. The experimental study has allowed the demonstration of the influence of the key parameters on the observed behavior and more specifically, on the local friction at the interface. We examined, in particular, the influence of amplitude of cyclic displacement, the frequency of cyclic loading and the applied number of cycles. Emphasis was put on the case of large number of a few hundred thousand of cycles that is still little studied in the literature. We also study the influence of initial consolidation pressure. The experimental results allowed us to identify, after an initial phase of stress softening, a new phase of stress hardening of local friction. This behavior is not yet described in the literature. The stress softening phase is related to the progressive generation of pore water pressure while the stress hardening, for its part, is related to a gradual dissipation of the generated pore water pressure. Furthermore, a complete sequence of monotonic and cyclic tests were conducted on a piezocone in order to quantify, in a precise manner, the generated pore water pressure at the pile-soil interface during different loading phases and thus validate interpretations given for stress-softening and stress-hardening phases based on the observed results
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Baldock, Jeffrey Alexander. "Influence of calcium on the decomposition of organic materials in soils / Jeffrey Alexander Baldock". Thesis, 1989. http://hdl.handle.net/2440/18962.
Testo completoAbstract (sommario):
Includes bibliographical references.1 v. ; 30 cm.
The mechanism(s) by which calcium stabilises soil organic carbon against microbial attack was investigated in this study.
Thesis (Ph.D.)--University of Adelaide, Dept. of Soil Science, 1989
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Muneer, Muhammad. "Effect of calcium on the mineralization of organic carbon and stability of soil aggregates / by Muhammad Muneer". 1987. http://hdl.handle.net/2440/18532.
Testo completoAbstract (sommario):
Bibliography: leaves 172-189xviii, 189 leaves : ill. (1 col.) ; 31 cm.
Title page, contents and abstract only. The complete thesis in print form is available from the University Library.
Thesis (Ph.D.)--University of Adelaide, Dept. of Soil Science, Waite Agricultural Research Institute, 1987
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Muneer, Muhammad. "Effect of calcium on the mineralization of organic carbon and stability of soil aggregates / by Muhammad Muneer". Thesis, 1987. http://hdl.handle.net/2440/18532.
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Suriadi, Ahmad. "Structural stability and Na-Ca exchange selectivity of soils under sugarcane trash management". Thesis, 2001. http://hdl.handle.net/2440/110238.
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Cichota, Rogerio. "Modelling sulphate dynamics in soils : the effect of ion-pair adsorption : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Soil Science at Massey University". 2007. http://hdl.handle.net/10179/1443.
Testo completoAbstract (sommario):
Sulphur is an important nutrient to plants, and reports of its deficiency have been increasing worldwide. Sulphur starvation causes losses in both yield and quality, and it reduces nitrogen use efficiency of plants. As the timing for fertilisation can be decisive for avoiding deleterious effects, improvements in the description of the sulphur balance in fields are a valuable contribution for assisting fertiliser management. Sulphate is the most important inorganic form of sulphur in soils. Being the mobile form, sulphate is readily available for plants, and also prone to be leached. Therefore the description of the movement of sulphate is the key component of the sulphur balance. Leaching of sulphate from the soil can be significantly delayed by its adsorption onto the soil particles. Soil type and pH are the main factors defining the sulphate adsorption capacity; although the presence of other ions in the soil solution can have a considerable effect. It has been reported that in some soils, typically volcanic and tropical soils with variable-charge characteristics, the co-presence of sulphate and calcium can substantially enhance their retention via ion-pair adsorption (IPA). To determine the influence of cations on the movement of sulphate, series of batch and miscible displacement experiments were conducted using two New Zealand soils, of contrasting ion adsorption capacities: the Taupo sandy and Egmont loam soils. These experiments demonstrated the occurrence of cooperative adsorption of sulphate and calcium in the Egmont soil, but not in the Taupo soil. Batch experiments were conducted to examine the IPA adsorption process in the Egmont soil in more detail. Based on the analyses of the results from these two series of experiments, plus the review of published data, three different mathematical approaches for evaluating the amount of solute adsorbed as ion-pairs are proposed. A computer program was built for solving an adsorption model using these three approaches, and was used to compare the model's predictions and the observed adsorption data. An extension of this program, coupling the adsorption model with a solute transport description, was used to simulate the movement of sulphate and calcium. Comparisons between the data from the miscible displacements and the results from this model are used to demonstrate the applicability of the proposed IPA description for modelling the transport of these ions in the soil. Finally, results from a pot trial with Egmont soil are used to examine the relevance of IPA for the movement of sulphate under non-equilibrium conditions, and with active plant growth. Although the results from this experiment regarding IPA were statistically non-significant, some insights could be obtained and are discussed. More studies involving IPA under non-equilibrium experiments are needed for a better understanding of the relevance of IPA in field conditions.
Libri sul tema "Soils Calcium content"
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Greulich, Peter. Schwermetalle in Fichten und Böden im Burgwald (Hessen): Untersuchungen zur räumlichen Variabilität der Elemente Blei, Cadmium, Nickel, Zink, Calcium und Magnesium, unter besonderer Berücksichtigung des Reliefeinflusses. Marburg/Lahn: Im Selbtsverlag der Marburger Geographischen Gesellschaft, 1988.
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The distribution of calcium carbonate in soils: A computer simulation using program CALSOIL. [Denver, Colo.]: U.S. Dept. of the Interior, Geological Survey, 1986.
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Geological Survey (U.S.), a cura di. The distribution of calcium carbonate in soils: A computer simulation using program CALSOIL. [Denver, Colo.]: U.S. Dept. of the Interior, Geological Survey, 1986.
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Geological Survey (U.S.), a cura di. The distribution of calcium carbonate in soils: A computer simulation using program CALSOIL. [Denver, Colo.]: U.S. Dept. of the Interior, Geological Survey, 1986.
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Australian Soil Fertility Manual. CSIRO Publishing, 2006. http://dx.doi.org/10.1071/9780643100725.
Testo completoAbstract (sommario):
The Australian Soil Fertility Manual is a trusted guide to the safe use and handling of fertilizers. It describes the types of agricultural soils, how they are classified and the interaction of soil, water and nutrients. It also provides an insight into how plants utilise nutrients and the role that individual nutrients play in the process of plant growth.
This edition has been revised to reflect an increased emphasis on the environmental fate of nutrients and appropriate management strategies. It also has additional information on soil physical, chemical, and biological properties and discussions on the use of lime, dolomite and gypsum.
New content covers liming effectiveness, nitrogen water use efficiency, regulations for handling and using fertilizers, storage and transport of security sensitive ammonium nitrate, budgeting for profitable nitrogen use and best management practice for nitrogen and phosphorus fertilizers. The chapters on potassium; calcium, magnesium and sulfur; plant nutrients and the environment; and heavy metal in fertilizers and agriculture have all been extensively revised and rewritten.
This important work will be an essential text for fertilizer dealers, extension workers, consultants, teachers, farmers, horticulturists, graziers and others concerned with the profitable and environmentally safe use of plant nutrients.
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Zachara, John Michael. A solution chemistry and electron spectroscopic study of zinc adsorption and precipitation on calcite. 1987.
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Laboratory data for calcic soils in central New Mexico: Background information for mapping Quaternary deposits in the Albuquerque Basin. Denver, Colo: U.S. Dept. of the Interior, U.S. Geological Survey, 1997.
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Kacorzyk, Piotr. Wartość gospodarcza okrywy roślinnej gleby w aspekcie nawożenia oraz zdolności retencyjnej płytki gleby górskiej. Publishing House of the University of Agriculture in Krakow, 2018. http://dx.doi.org/10.15576/978-83-66602-33-5.
Testo completoAbstract (sommario):
The aim of the study was to assess the impact of method management of mountain soil on the quantity and quality of waste water, and the amount of mineral nutrients it contains. I have analyzed the water, that was moved through the soil profiles of 0-20 cm and 0-40 cm depth. I have also evaluated the floristic composition, the productivity of grassland and arable land, and the use of fertilizers by vegetation and soil chemical properties. I have found that the type of plant cover of the soil had a significant effect on the amount and chemical composition of water moving through the soil profile. Arable land was characterized by an average of 5 percentage point higher drainage rates compared to meadows. The smallest outflow of water from the soil was found in the first research period (intensive vegetation), and the largest in the third period (non-vegetation). The largest amount of the mineral content carried out annually with a soaking water, was observed on the arable land and was on average more than 2 times larger than on other fertilizers. This evidenced by the greater variation in the composition of floristic vegetation and its productivity. Between 0-20 cm and 0-40 cm of soil profiles, significant differences in the amount of waste water and mineral components were observed. The water drainage coefficient from the shallow profile was on average 9 percentage points higher than from the deeper profile. The amount of the sum of mineral loads, excluding calcium from the shallow soil profile was 94,5% higher than the sum of loads taken from the deeper soil profile. In the unused meadow the improvement of soil chemical properties was observed. There was an increase in pH, and the accumulation of minerals resulted from the positive balance of most of the ingredients.
Capitoli di libri sul tema "Soils Calcium content"
1
Kuria, Peter, Josiah Gitari, Saidi Mkomwa e Peter Waweru. "Effect of conservation agriculture on soil properties and maize grain yield in the semi-arid Laikipia county, Kenya." In Conservation agriculture in Africa: climate smart agricultural development, 256–69. Wallingford: CABI, 2022. http://dx.doi.org/10.1079/9781789245745.0015.
Testo completoAbstract (sommario):
Abstract Low and unreliable rainfall, along with poor soil health, is a main constraint to maize production in the semi-arid parts of Kenya that account for over 79% of the country's land area. In the vast county of Laikipia, farmers continue to plant maize despite the predominantly low quantities of precipitation. Participatory farmer experimentation with Conservation Agriculture (CA) was undertaken for six consecutive growing seasons between July 2013 and December 2016 to determine the effectiveness of CA as a method of improving soil properties and enhancing maize yields with the limited rainfall quantities received in these parts of Kenya. The main CA practices tested include chisel tine furrow opening (ripping) and live legume (Lablab purpureus) cover crop, as well as maize stover mulches, all implemented under varying inorganic fertilizer rates. The research was done across 12 administrative locations of Laikipia County where soils are mainly Phaeozems and Vertisols with a clay-loam texture. The research design used was researcher-designed and farmer-managed. In each of the 12 trial sites, participatory farmers' assessments and field days were carried out as a way of outreach to the bigger farming communities around the trial sites. The research findings obtained demonstrated that the use of CA impacts positively on soil properties and is a viable practice for enhancing maize yields in these moisture deficit-prone parts of the country. Soil chemical analysis assessment results showed that CA impacted positively on a number of soil mineral components including organic carbon, total nitrogen, phosphorus, potassium, calcium and pH. Midseason chlorophyll content assessment of the maize crop showed that there was good response to fertilizer application, as well as to mulching with crop residues for soil cover. Maize grain yield data also showed that the use of a CA package comprising chisel tine ripping combined with mulching by plant residues and use of mineral fertilizer resulted in a two- to threefold increase in grain yields above the farmer practice control. Mean maize grain yield in farmer practice plots was 1067 kg ha-1 compared with the CA-treated plot with mineral fertilization that yielded 2192 kg ha-1.
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Reddy, Peddireddy Sreekanth, Bijayananda Mohanty e Bendadi Hanumantha Rao. "Influence of Exchangeable Sodium and Calcium Contents on Consistency Limits of Expansive Soils: A Critical Review". In Lecture Notes in Civil Engineering, 299–306. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-5077-3_24.
Testo completo
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Egginton, Gwen M., e Ka Smith. "Relationships between soil mineral nitrogen content and denitrification, following application of slurry and calcium nitrate to grassland". In Nitrogen Fluxes in Intensive Grassland Systems, 75–83. Dordrecht: Springer Netherlands, 1986. http://dx.doi.org/10.1007/978-94-009-4394-0_7.
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Wang, J. H. "Lime Potential". In Chemistry of Variable Charge Soils. Oxford University Press, 1997. http://dx.doi.org/10.1093/oso/9780195097450.003.0015.
Testo completoAbstract (sommario):
The properties of hydrogen and aluminum ions have been examined in Chapters 10 and 11. These two ion species are ions that directly induce the acid reaction in soils. In soils devoid of soluble salts, the content of cations is constant and the negative surface charges are saturated by, besides hydrogen and aluminum ions, alkali metal and alkaline earth metal ions. These ions are called base ions. The acidity of a soil is determined chiefly by the ratio of the quantity of hydrogen and aluminum ions to that of base ions. Among these base ions, calcium ions occupy the most important position, because they generally account for 65-80% of the total amount of base ions in variable charge soils. Therefore, calcium is an ion species closely related to the acidity of soils. In addition to the parameter pH that directly reflects the concentration of hydrogen ions, one other desirable way is to find a parameter that can reflect the ratio of the hydrogen ions to the calcium ions. This parameter is the lime potential. Since the introduction of the concept of lime potential 40 years ago, little practical application has been made in soil science, although some further theoretical considerations were advanced in the 1950s and the 1960s. Actually, as shall be seen in this chapter, for strongly acid soils, such as variable charge soils, because the quantity of hydrogen ions is too high and at the same time the quantity of calcium ions is too low, lime potential that can reflect the relative ratio of these two ion species is of significance not only in theory but also in practice. The mathematical expression of lime potential is pH-0.5pCa. Lime potential is a simple function of the chemical potential of calcium hydroxide, lime. Hence it may be called lime potential. The physical meaning of pH-0.5pCa can be derived as follows.
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Leenheer, Jerry A., e Gary E. Maciel. "Preparation of Low-Carbon Sediments from the Mississippi River and Certain Tributaries for Solid-state CPMAS 13C NMR Analysis". In Nuclear Magnetic Resonance Spectroscopy in Environment Chemistry. Oxford University Press, 1997. http://dx.doi.org/10.1093/oso/9780195097511.003.0024.
Testo completoAbstract (sommario):
The nature of organic carbon in aquatic sediments and soils with low carbon contents and significant contents of paramagnetic elements such as iron and manganese is difficult to assess by solid-state, cross-polarization magic angle spinning (CPMAS) 13C nuclear magnetic resonance (NMR) spectrometry because of the inherent low sensitivity of 13C NMR analyses, and band broadening and sensitivity losses caused by paramagnetic elements. Other investigators have addressed this problem in the analysis of soils by enriching the organic carbon content by flotation, by magnetic separation of paramagnetic minerals, and by chemical reduction of iron by stannous chloride and sodium dithionite. In this study, they found that satisfactory 13C NMR spectra could be obtained if the C/Fe ratio was greater than 1 wt%. Each of the physical and chemical treatments used to increase the C/Fe ratio resulted in losses of organic matter and changes in the nature of organic matter through physical fractionation and chemical alteration. Suspended stream sediments frequently have equivalent contents of organic carbon and sesquioxide coatings with which the organic matter is associated. These sesquioxide coatings consist predominantly of iron and manganese oxyhydroxides that cause problems with NMR analyses. In this chapter we describe a method to enrich organic matter and remove iron and manganese from low-carbon sediments sampled from the Mississippi, Illinois, and Ohio Rivers with minimal loss and alteration of the organic matter. The second objective is to characterize the sedimentary organic matter by 13C NMR using recent advances that increase instrument sensitivity. Suspended and bed sediments were collected during a sampling cruise on the Mississippi River during May–June 1990. Fine bed sediments were collected in depositional regions of the river or tributaries with a pipe dredge. Suspended silts were collected using a continuous-flow centrifuge operated on board the Research Vessel Acadiana. Both bed sediments and suspended silts were freeze-dried prior to additional treatment procedures and NMR analyses. A flow chart of selective mineral dissolution procedures is presented in Figure 17.1. The acid pyrophosphate treatment6 was placed first in the sequence to remove calcium and magnesium minerals that would form insoluble oxalates in the following extraction.
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Kelly, Eugene F., e Caroline M. Yonker. "Soil Development and Distribution in the Shortgrass Steppe Ecosystem". In Ecology of the Shortgrass Steppe. Oxford University Press, 2008. http://dx.doi.org/10.1093/oso/9780195135824.003.0007.
Testo completoAbstract (sommario):
Beneath the gently rolling, seemingly mundane topography that characterizes the shortgrass steppe is a complex mosaic of soils. Many of these soils are superimposed upon older, buried soils that formed in other millennia under different climatic regimes. The nature of this soil mosaic reveals much about the past and dictates much about the future of the shortgrass steppe. There is considerable heterogeneity among soils of the shortgrass steppe, yet they maintain a high degree of homogeneity when contrasted with soils of other ecosystems. The driving forces that make these soils alike are a semiarid climate and a resilient plant community ( P ielke and Doesken, chapter 2, this volume; and Lauenroth, chapter 5, this volume). The combined effects of vegetation and climate on soil development yield generally predictable results. Shortgrass steppe soils are characterized by the accumulation of organic matter in the surface (0–20 cm). Approximately 60% of the graminoid root mass resides in the - rst 10 cm of mineral soil (Schimel et al., 1986); 90% is contained in the surface 20 cm (Schimel et al., 1985). Surface horizons typically are darker hued than underlying horizons and have organic carbon contents that average 1% to 3% (Yonker et al., 1988). Shortgrass steppe soils maintain a high-percent base saturation (and high pH) because of low leaching and weathering potentials that result from semiarid conditions. Zones of secondary calcium carbonate accumulation are common in subsurface horizons and may appear as threads, seams, or nodules (Blecker et al., 1997). In addition, these soils are characterized by zones of secondary clay accumulation in subsurface horizons; clay accumulations are a result of either the in situ weathering of primary minerals or the translocation of clay minerals leached from the surface horizon. In either case, the maximum depth of accumulation gives some indication of the time-averaged depth of the wetting front in the soil pro- le (Blecker et al., 1997). The factors that produce considerable heterogeneity among the soils of the shortgrass steppe are related to parent material, the age of the soil, and the subtleties of topography. These factors vary at a - ner scale than either vegetation or climate.
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Pooley, Justin, e Martin Fey. "Soil Nutrient Deficiencies in an Area of Endemic Osteoarthritis (Mseleni Joint Disease) and Dwarfism in Maputoland, South Africa". In Geology and Health. Oxford University Press, 2003. http://dx.doi.org/10.1093/oso/9780195162042.003.0032.
Testo completoAbstract (sommario):
Unusually high incidences of dwarfism and an endemic osteoarthritis, called Mseleni Joint Disease (MJD), occur on the flat, sandy coastal plain of Maputaland. This rare disease begins with stiffness and pain in the joints and progresses to varying degrees of disability, with some of the afflicted requiring aid in walking and others completely immobile. Almost 3% of local adults are dwarfs, while 38% of women and 11% of men have MJD (Fellingham 1973, Lockitch 1974). Medical studies since the 1970s have examined hematological, radiological, mycotoxicological, and genetic factors, and made comparisons with other diseases (Ballo 1996, Burger 1973, Lockitch 1973, Marasas 1986), yet have been fruitless in determining the etiology of MJD or the dwarfism. Dwarfism has been linked to Zn deficiencies in other areas and several bone-related disorders have been associated with P, Ca, and Mg deficiencies (Hidiroglou 1980). Calcium, Mg, Mn, and F deficiencies have all been speculated as possible causative factors of MJD (Fincham 1981, 1986), and the possibility of soil-derived nutrient deficiencies within this landscape is addressed. Maputaland is located on the northeast corner of South Africa, occupying an area about 50 by 100 km. It has a warm, subtropical climate, with summer rainfall occurring as cyclonic events, and varying from 1000 mm at the coast to 600 mm near Mseleni. Summer temperatures are high, averaging 29° C, and winters mild at 17° C. The region has high floral and faunal diversity and endemism (van Wyk 1996), and contains 15 major vegetation zones. Geologically, Maputaland is covered with recent Quaternary sands, with several north-south paleodune cordons parallel to the coast. There is little relief and, besides the coastal dunes reaching almost 200 m above mean sea level, the average elevation is 100 m. No rivers cross the plain, but groundwater is frequently exposed at the surface, as evidenced by Lake Sibayi and the numerous pans in the region. Soils are mostly the Waterton family of the Fernwood form (thermic, coated Typic Quartzipsamments) (SCWG 1991, USDA 1999). These sands are inherently infertile, vary in pH from neutral to acidic, have a low cation exchange capacity, low organic matter content, and are dominated in the clay fraction by kaolinite.
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Alves de Oliveira, Herbet, e Cochiran Pereira dos Santos. "Limestone Clays for Ceramic Industry". In Clay Science and Technology. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.92506.
Testo completoAbstract (sommario):
Limestone clays are used in the ceramic segment in the manufacture of bricks, ceramic tiles, and in the production of cement, among others. Limestone can be present in soils in pure form or as a contaminant, but always from marine environments. The limestone after burning can present a high loss of mass (35–45%), which can cause serious problems with the sintering of ceramic products such as bricks, tiles. The calcium or magnesium carbonate once dissociated forms calcium oxide (CaO) and releases carbon dioxide (CO2). CaO in contact with water subsequently experiences very high expansions that can cause cracks in the materials. Researchers have studied procedures to inhibit limestone action on clays as well as to set the correct temperature for firing. In this chapter, examples of clays with different percentages of calcium carbonate (CaCO3) that are used in the ceramic segment and their characteristics will be given.
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Massa Ismaël, Bamba, e Sorho Siaka. "The Toxicity of Environmental Pollutants". In The Toxicity of Environmental Pollutants. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.104088.
Testo completoAbstract (sommario):
In view of the growing threat of trace metals to human health, this work set itself the objective of documenting the toxicity of the trace metals most in contact with humans on human health through food. Thus, this study revealed that organic matter, pH and CEC are the main soil parameters that influence the passage of trace metals from soil to plants. The study also revealed that agriculture, industry and road traffic contribute greatly to the input of trace metals into the environment. Regarding the mechanisms of toxicity, the study showed that chromium VI and copper manifested their toxicity by the formation of free radicals after reduction, those of zinc, nickel, manganese and nickel resulting from the disfunctioning of homeostasis. The study showed that lead caused toxic effects by replacing certain cations such as Ca2+, Mg2+, Fe2+, Na+ which have important functions in the cell. Cadmium expresses its toxicity by binding to albumin, thus altering the homeostasis of metals such as calcium. All these mechanisms have revealed both acute and chronic toxic effects.
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Malik, Junaid Ahmad. "Urban Solid Waste Management Techniques With Special Reference to Vermicomposting". In Advances in Environmental Engineering and Green Technologies, 53–79. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-1966-0.ch003.
Testo completoAbstract (sommario):
The majority of municipal (urban) solid waste (MSW) is disposed of in landfills (anaerobic composting). However, this disposal system is reported to produce hazardous environmental impacts, and new policies are initiated to protect the environment from such impacts by discouraging the practice of disposal of solid waste in landfills. Eco-friendly disposal alternatives to landfills need to be explored. One of the technological options for treatment and disposal of organic solid wastes is vermicomposting. Instead of using conventional composting methods, the vermicomposting method can be used for the disposal of the waste. The enzymatic and microbial activities that occur during vermicomposting process by worms gives a better end product than using the conventional composting. Food waste will be recovered for vermicomposting, and the end products can be organic fertilizer, soil improver, and an alternative source of potential energy. Vermicomposting or vermiculture is an eco-friendly process whereby worms are used to breakdown the organic waste into soil and humus known as vermicast, vermicompost, or earthworm compost. The objective is to process the organic material as quickly and efficiently as possible. During the breakdown of organic matter by the earthworm, humus, which is a complicated material, is formed. The material formed is high in content of nitrogen, calcium, and phosphorus, which are the main elements required by plants for their growth, health, and freshness.
Atti di convegni sul tema "Soils Calcium content"
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Bulimaga, Constantin, e Corina Certan. "Evaluarea impactului ecositemelor urbane asupra mediului în regiunea de dezvoltare economica Centru". In Impactul antropic asupra calitatii mediului. Institute of Ecology and Geography, Republic of Moldova, 2019. http://dx.doi.org/10.53380/9789975330800.04.
Testo completoAbstract (sommario):
Regardless of the fact that both urban ecosystems studied – Orhei and Telenești – have purification stations, they are still an essential source of surface water pollution. The aqueous soil extract (Telenești) has a pH value of 8 up to 9.8 due to the high content of calcium and potassium in the soil, due to the fact that the area under investigation has a specific character caused by the spread of solonetz-type soils, solonized chernozems, and salinated soils. The anthropogenic impact in urban ecosystems produces an imbalance in the ratio of spontaneous species and ruderal and ruderal-segetal species. The number of spontaneous species is the indicator of the degree of anthropization in urban ecosystems. Urban ecosystems have a major impact on the environment.
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Malikzada, Abdulmuner, Hasan Fırat Pulat e İnci Develioğlu. "Effect of Fly Ash on Compaction Behavior of Alluvial Soil". In International Students Science Congress. Izmir International Guest Student Association, 2021. http://dx.doi.org/10.52460/issc.2021.016.
Testo completoAbstract (sommario):
Low plasticity, high bearing capacity, low settlement, etc. are the preferred properties for most engineering projects. Alluvial soils are problematic soils because of low bearing capacity, high organic matter content, and high void ratio so they do not meet the preferred condition for engineering projects. It has been necessary to improve unsuitable materials to make them acceptable for construction. Fly ash (FA) has earlier been used for stabilizing roads due to its high content of calcium and silicate oxides which give puzzolanic properties and thus high compression strength. In this research, fundamental engineering properties, compaction behaviors of three types of (fine, medium, and coarse) alluvial deposits, and the effect of fly ash on compaction behavior of these alluvial soils are presented. Alluvial soil is taken from Çiğli, Balatçık (Izmir, Turkey). To determine geotechnical index properties; wet sieve analysis, plastic limit, liquid limit, specific gravity, standard compaction tests were conducted. In order to determine the effect of fly ash on compaction behavior of alluvial deposits, three different samples (fine < 0.425mm, medium < 2mm, and coarse < 4.75 mm) are prepared and 10%, 15%, 20% fly ash by dry weight of soil is mixed and standard proctor test is performed. As a result of laboratory tests, the liquid limit, plastic limit, and plasticity index values obtained as 38.3%, 25.7%, and 12.6%, respectively. The specific gravities for fine, medium, and coarse samples are 2.68, 2.67, and 2.66, respectively. According to the results of wet sieve analysis and consistency limit tests, it was stated that the soil contains large amounts of sand and clay. The washed sieve analysis and consistency limit tests results were evaluated according to USCS. The conducted test results have shown that maximum dry unit weight for fine, medium, and coarse soils are 16.9, 19.35, and 19.55 (kN/m3), and optimum moisture content for fine, medium, and coarse samples are 17, 11, 10.5% respectively. Generally, by increasing the content of FA, maximum dry unit weight decreased and optimum moisture content increased for all three types of alluvial soil. By increasing FA to 20%, maximum dry unit weight of medium and coarse soils decreases 1.5% and 2%, respectively.
3
Kuleshova, L. A., A. S. Kasakova e I. S. Tatyanchenko. "INFLUENCE OF PRECURSORS ON THE CONTENT OF MINERAL PHOSPHORUS FRACTIONS IN THE SOILS OF RICE FIELDS IN THE ROSTOV REGION." In STATE AND DEVELOPMENT PROSPECTS OF AGRIBUSINESS Volume 2. DSTU-Print, 2020. http://dx.doi.org/10.23947/interagro.2020.2.704-708.
Testo completoAbstract (sommario):
The article is devoted to the problem of phosphoric nutrition of rice on chestnut soils of the northernmost zone of rice cultivation in Russia. The paper reveals the role of water-soluble fractions of phosphorus, aluminosilicates, iron phosphates and calcium phosphates in the nutrition of rice plants during the growing season. The influence of the previous culture on the content and consumption of these fractions was established.
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Labrador, Y., C. Chang e J. Viloria. "Prediction of the Calcium and Magnesium Content in Soils through a Generalized Regression Neural Networks and Genetic Algorithms". In 2012 Eleventh International Conference on Machine Learning and Applications (ICMLA). IEEE, 2012. http://dx.doi.org/10.1109/icmla.2012.123.
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Skripnikov, P., e A. Nalivaichenko. "ACCUMULATION OF ORGANIC CARBON UNDER WOODY PLANT COMMUNITIES IN URBAN FORESTS OF ROSTOV-ON-DON". In Reproduction, monitoring and protection of natural, natural-anthropogenic and anthropogenic landscapes. FSBE Institution of Higher Education Voronezh State University of Forestry and Technologies named after G.F. Morozov, 2022. http://dx.doi.org/10.34220/rmpnnaal2021_97-102.
Testo completoAbstract (sommario):
The paper provides an analysis of the vegetation state and soil cover of the "Temernitskaya Roscha" and the "Schepkinsky Les" artificial recreational forests which located in the Rostov-on-Don city. Geobotanical descriptions were carried out according to the standard method to species diversity assessing. The “Temernitskaya Roscha" recreational forests has been affected by anthropogenic pressure, but its grass cover was more diverse than in the "Schepkinsky Les" recreational forests where tree plant species was dominated. The study of the soil cover revealed a statistically significant increase of the organic matter content in the AUrz surface horizon. This increase was noted in soils under woody vegetation, in comparison with steppe zones which are typical for our region. In the underlying AU horizons, the accumulation and distribution of Corg, in turn, has a similar character for all studied soils. There are no significant differences between the chernozems of the forest park zone and fallow territories in the accumulation and distribution of Corg. The calcium carbonates profile distribution under woody vegetation is characterized by a decrease in the carbonated depth, visual blurriness of the presence of carbonates and the presence of rarely encountered lime nodules in the lower part of the profile.
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PEKARSKAS, Juozas, Algirdas GAVENAUSKAS, Anželika DAUTARTĖ e Aida STIKLIENĖ. "RECYCLING OF MINERAL SERPENTINITE WASTE FROM MINING INDUSTRY AND ITS USE IN AGRICULTURE TO IMPROVE SOIL AGROCHEMICAL PROPERTIES". In RURAL DEVELOPMENT. Aleksandras Stulginskis University, 2018. http://dx.doi.org/10.15544/rd.2017.102.
Testo completoAbstract (sommario):
The influence of processing the serpentinite quarry from the Caucasian mountains at the foot of the Mount Elbrus crushed waste on soil agrochemical properties, phytotoxicity of spring barley, influence on barley plant biomass and its chemical composition were investigated. Ground and granular serpentinite had a different effect on soil and plants. Application of serpentinite fertilizers significantly increased the content of calcium, iron, 227.95-376.75 and 5.05-9.62 mg kg-1, total and plant-derived magnesium 0.34-0.52 and 1.19-2.16 mg kg-1, lead and nickel, while the amount of copper dropped substantially; the soil was becoming more alkaline. Application of ground serpentinite lead to alkalizing of the soil much more compared to the granular, with a significant increase in plant-derived magnesium. The influence of serpentinite increased the yield of spring barley plants in green and dry mass by 0.049-0.256 and 0.011-0.046 g or 0.65-3.41 and 1.19-2.59% out of the growing vessel, and dry matter increased by 0.12-0.26 % units, the yield of spring barley green and dry mass under the influence of ground serpentinite was higher than of granular serpentinite fertilizer, and the dry matter was found to be significantly higher than that of unfertilized spring barley plants. Ground and granular serpentinite was not phytotoxic to spring barley. An application of ground serpentinite increased an amount of calcium, potassium and magnesium in the barley dry matter compared to the granular serpentinite. Ground and granular serpentinite reduced the amount of trace elements copper and manganese in the dry mass of the plant, and the amount of zinc decreased only after fertilization with granular serpentinite. An application of serpentinite significantly decreased content of lead, chrome and cadmium while nickel content significantly increased in the dry matter of barley plants.
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Karklina, Ilze, Zaiga Anna Zvaigzne e Jelena Stola. "Chemical properties of needles as an indicator of nutrient status of fertilized coniferous stands". In Research for Rural Development 2020. Latvia University of Life Sciences and Technologies, 2020. http://dx.doi.org/10.22616/rrd.26.2020.012.
Testo completoAbstract (sommario):
Enhanced forest growth may respond to demand of woody resources and contribute to the climate change mitigation. Forest soil treatment with fertilizers, as well as drainage and thinning enhance forest growth. The analysis of needles is an established method in forest science to identify the nutrient status in the forest stand and need for forest soil enrichment with fertilizers. The aim of this research is to estimate the efficiency of forest soil enrichment with wood ash and ammonium nitrate in order to eliminate nutrient deficiency in forest stands. Forest soil was enriched with wood ash fertilizer or ammonium nitrate in 2016–2017. The current year needles were collected from fertilized and control plots, from three trees in each plot. The samples were collected in the period 2018–2019. Total nitrogen (g kg-1), calcium (g kg-1), magnesium (g kg-1), and potassium (g kg-1) were analyzed in the collected samples. The chemical properties of collected needles were compared at the individual object level to estimate the impact of fertilizer on forest stand. A statistically significant increase in the concentrations of potassium and phosphorus was detected in some plots treated with wood ash and ammonium nitrate. In addition, a correlation analysis conducted between the variables of chemical properties of needles and soil showed few significant correlations between nutrient content in needles and in soil samples.
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A R, Sindhu, Minukrishna P e B. M. Abraham. "Experimental Study on the Impact of Type of Sulphate in Lime Stabilised Clays". In International Web Conference in Civil Engineering for a Sustainable Planet. AIJR Publisher, 2021. http://dx.doi.org/10.21467/proceedings.112.14.
Testo completoAbstract (sommario):
Marine clays are distinguished by high compressibility and low shear strength. It has been reported that lime stabilisation is very much potent, and can be used as an ideal ground improvement technique in the case of marine clays. Cochin marine clays are sometimes abundant in primary and secondary sources of sulphates of sodium, lithium, potassium and calcium. Different types of sulphates may have different impact on lime stabilised clays. Present study investigates the effect of different types of sulphates in lime treated marine clays. Marine clay samples were collected by auger boring and all the physical properties were determined. Sulphate content in clay was also found. Clay samples were treated with 6% of lime and 4% of sodium sulphate, lithium sulphate and potassium sulphate and were kept for various curing periods of zero days, 1 week, 1 month, 3 months and 6 months. Atterberg limits, free swell index, unconfined compressive strength and pH of all samples were determined. It was found that the plasticity and swelling characteristics of lime treated clay were influenced by the addition of sulphates. It was also found that all the three types of sulphates had detrimental effect on the gain in strength of lime stabilised soil. But the effect varies significantly with the type of sulphate present in the clay. This necessitates the importance of determination of the type sulphate present in the marine clay, before planning the soil stabilisation using lime.
Rapporti di organizzazioni sul tema "Soils Calcium content"
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Савосько, Василь Миколайович, Юлія Віліївна Бєлик, Юрій Васильович Лихолат, Герман Хайльмейер, Іван Панасович Григорюк, Ніна Олександрівна Хромих e Тетяна Юріївна Лихолат. The Total Content of Macronutrients and Heavy Metals in the Soil on Devastated Lands at Kryvyi Rih Iron Mining & Metallurgical District (Ukraine). Geology-dnu-dp.ua, 2021. http://dx.doi.org/10.31812/123456789/4286.
Testo completoAbstract (sommario):
The relevance of the research is due to the need to develop technologies for phytoremediation of the devastated lands in the mining and metallurgical regions of Ukraine and the world. In this regard, the creation of tree plantations adapted to the ecological conditions of such territories is considered by many experts as the most promising option for innovative technologies. However, the development of artificial woodlands requires knowledge of the pedogeochemical character- istics of devastated lands. The aim of the work was to carry out a comparative analysis of the macronutrients and heavy metals gross forms content in the soils of the devastated lands of the Kryvyi Rih mining and metallurgical region. The field studies focused on five contrasting monitoring sites of the Petrovsky dump (Central Kryvorizhzhya), which has a typical age and composition of rocks for the region. Soil sampling, drying, sieving, and sample preparation (sintering in a muffle furnace) were done in accordance with classical techniques. The concentrations of macronutrients (potassium, sodium, calcium, magnesium, sulfur, and phosphorus) and heavy metals (iron, manganese, zinc, copper, lead, and cadmium) were determined using an Inductively Coupled Plasma Mass Spectrometry (ICP- MS) X-Series 2 (Thermo Fisher Scientific, USA). The analytical part of our research was carried out on the basis of the laboratory of the Institute of Biosciences, Freiberg University of Technology and Mining Academy (Freiberg, Germany). At monitoring sites, significant differences were found in the content of macronutrients gross forms, and their variation relative to the control values as well. Potassium and sodium concentrations generally differed slightly or were close to control levels. The results of determining the content of calcium, magnesium and phosphorus indicate a significant deficiency or excess of these macronutrients in the soils of the devastated lands. An increased sulfur content was found in the soils of all monitoring sites, in some cases 4 times higher than the control level. The measured content of gross forms of iron, manganese, copper, cadmium and, partially, zinc in the soils of different monitoring sites exceeded the control values by 5.5 – 5.9 times. Thus, the analysis of the research results made it possible to establish that the soils of the devastated lands of the Petrovsky dump are characterized by unfavorable properties for the growth of most species of woody plants.
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Shenker, Moshe, Paul R. Bloom, Abraham Shaviv, Adina Paytan, Barbara J. Cade-Menun, Yona Chen e Jorge Tarchitzky. Fate of Phosphorus Originated from Treated Wastewater and Biosolids in Soils: Speciation, Transport, and Accumulation. United States Department of Agriculture, giugno 2011. http://dx.doi.org/10.32747/2011.7697103.bard.
Testo completoAbstract (sommario):
Beneficial use of reclaimed wastewater (RW) and biosolids (BS) in soils is accompanied by large input of sewage-originated P. Prolonged application may result in P accumulation up to levelsBeneficial use of reclaimed wastewater (RW) and biosolids (BS) in soils is accompanied by large input of sewage-originated P. Prolonged application may result in P accumulation up to levels that impair plant nutrition, increase P loss, and promote eutrophication in downstream waters. This study aims to shed light on the RW- and BS-P forms in soils and to follow the processes that determine P reactivity, solubility, availability, and loss in RW and BS treated soils. The Technion group used sequential P extraction combined with measuring stable oxygen isotopic composition in phosphate (δ18OP) and with 31P-NMR studies to probe P speciation and transformations in soils irrigated with RW or fresh water (FW). The application of the δ18OP method to probe inorganic P (Pi) speciation and transformations in soils was developed through collaboration between the Technion and the UCSC groups. The method was used to trace Pi in water-, NaHCO3-, NaOH-, and HCl- P fractions in a calcareous clay soil (Acre, Israel) irrigated with RW or FW. The δ18OP signature changes during a month of incubation indicated biogeochemical processes. The water soluble Pi (WSPi) was affected by enzymatic activity yielding isotopic equilibrium with the water molecules in the soil solution. Further it interacted rapidly with the NaHCO3-Pi. The more stable Pi pools also exhibited isotopic alterations in the first two weeks after P application, likely related to microbial activity. Isotopic depletion which could result from organic P (PO) mineralization was followed by enrichment which may result from biologic discrimination in the uptake. Similar transformations were observed in both soils although transformations related to biological activity were more pronounced in the soil treated with RW. Specific P compounds were identified by the Technion group, using solution-state 31P-NMR in wastewater and in soil P extracts from Acre soils irrigated by RW and FW. Few identified PO compounds (e.g., D-glucose-6-phosphate) indicated coupled transformations of P and C in the wastewater. The RW soil retained higher P content, mainly in the labile fractions, but lower labile PO, than the FW soil; this and the fact that P species in the various soil extracts of the RW soil appear independent of P species in the RW are attributed to enhanced biological activity and P recycling in the RW soil. Consistent with that, both soils retained very similar P species in the soil pools. The HUJ group tested P stabilization to maximize the environmental safe application rates and the agronomic beneficial use of BS. Sequential P extraction indicated that the most reactive BS-P forms: WSP, membrane-P, and NaHCO3-P, were effectively stabilized by ferrous sulfate (FeSul), calcium oxide (CaO), or aluminum sulfate (alum). After applying the stabilized BS, or fresh BS (FBS), FBS compost (BSC), or P fertilizer (KH2PO4) to an alluvial soil, P availability was probed during 100 days of incubation. A plant-based bioassay indicated that P availability followed the order KH2PO4 >> alum-BS > BSC ≥ FBS > CaO-BS >> FeSul-BS. The WSPi concentration in soil increased following FBS or BSC application, and P mineralization further increased it during incubation. In contrast, the chemically stabilized BS reduced WSPi concentrations relative to the untreated soil. It was concluded that the chemically stabilized BS effectively controlled WSPi in the soil while still supplying P to support plant growth. Using the sequential extraction procedure the persistence of P availability in BS treated soils was shown to be of a long-term nature. 15 years after the last BS application to MN soils that were annually amended for 20 years by heavy rates of BS, about 25% of the added BS-P was found in the labile fractions. The UMN group further probed soil-P speciation in these soils by bulk and micro X-ray absorption near edge structure (XANES). This newly developed method was shown to be a powerful tool for P speciation in soils. In a control soil (no BS added), 54% of the total P was PO and it was mostly identified as phytic acid; 15% was identified as brushite and 26% as strengite. A corn crop BS amended soil included mostly P-Fe-peat complex, variscite and Al-P-peat complex but no Ca-P while in a BS-grass soil octacalcium phosphate was identified and o-phosphorylethanolamine or phytic acid was shown to dominate the PO fraction that impair plant nutrition, increase P loss, and promote eutrophication in downstream waters. This study aims to shed light on the RW- and BS-P forms in soils and to follow the processes that determine P reactivity, solubility, availability, and loss in RW and BS treated soils. The Technion group used sequential P extraction combined with measuring stable oxygen isotopic composition in phosphate (δ18OP) and with 31P-NMR studies to probe P speciation and transformations in soils irrigated with RW or fresh water (FW). The application of the δ18OP method to probe inorganic P (Pi) speciation and transformations in soils was developed through collaboration between the Technion and the UCSC groups. The method was used to trace Pi in water-, NaHCO3-, NaOH-, and HCl- P fractions in a calcareous clay soil (Acre, Israel) irrigated with RW or FW. The δ18OP signature changes during a month of incubation indicated biogeochemical processes. The water soluble Pi (WSPi) was affected by enzymatic activity yielding isotopic equilibrium with the water molecules in the soil solution. Further it interacted rapidly with the NaHCO3-Pi. The more stable Pi pools also exhibited isotopic alterations in the first two weeks after P application, likely related to microbial activity. Isotopic depletion which could result from organic P (PO) mineralization was followed by enrichment which may result from biologic discrimination in the uptake. Similar transformations were observed in both soils although transformations related to biological activity were more pronounced in the soil treated with RW. Specific P compounds were identified by the Technion group, using solution-state 31P-NMR in wastewater and in soil P extracts from Acre soils irrigated by RW and FW. Few identified PO compounds (e.g., D-glucose-6-phosphate) indicated coupled transformations of P and C in the wastewater. The RW soil retained higher P content, mainly in the labile fractions, but lower labile PO, than the FW soil; this and the fact that P species in the various soil extracts of the RW soil appear independent of P species in the RW are attributed to enhanced biological activity and P recycling in the RW soil. Consistent with that, both soils retained very similar P species in the soil pools. The HUJ group tested P stabilization to maximize the environmental safe application rates and the agronomic beneficial use of BS. Sequential P extraction indicated that the most reactive BS-P forms: WSP, membrane-P, and NaHCO3-P, were effectively stabilized by ferrous sulfate (FeSul), calcium oxide (CaO), or aluminum sulfate (alum). After applying the stabilized BS, or fresh BS (FBS), FBS compost (BSC), or P fertilizer (KH2PO4) to an alluvial soil, P availability was probed during 100 days of incubation. A plant-based bioassay indicated that P availability followed the order KH2PO4 >> alum-BS > BSC ≥ FBS > CaO-BS >> FeSul-BS. The WSPi concentration in soil increased following FBS or BSC application, and P mineralization further increased it during incubation. In contrast, the chemically stabilized BS reduced WSPi concentrations relative to the untreated soil. It was concluded that the chemically stabilized BS effectively controlled WSPi in the soil while still supplying P to support plant growth. Using the sequential extraction procedure the persistence of P availability in BS treated soils was shown to be of a long-term nature. 15 years after the last BS application to MN soils that were annually amended for 20 years by heavy rates of BS, about 25% of the added BS-P was found in the labile fractions. The UMN group further probed soil-P speciation in these soils by bulk and micro X-ray absorption near edge structure (XANES). This newly developed method was shown to be a powerful tool for P speciation in soils. In a control soil (no BS added), 54% of the total P was PO and it was mostly identified as phytic acid; 15% was identified as brushite and 26% as strengite. A corn crop BS amended soil included mostly P-Fe-peat complex, variscite and Al-P-peat complex but no Ca-P while in a BS-grass soil octacalcium phosphate was identified and o-phosphorylethanolamine or phytic acid was shown to dominate the PO fraction.
3
Litaor, Iggy, James Ippolito, Iris Zohar e Michael Massey. Phosphorus capture recycling and utilization for sustainable agriculture using Al/organic composite water treatment residuals. United States Department of Agriculture, gennaio 2015. http://dx.doi.org/10.32747/2015.7600037.bard.
Testo completoAbstract (sommario):
Objectives: 1) develop a thorough understanding of the sorption mechanisms of Pi and Po onto the Al/O- WTR; 2) determine the breakthrough range of the composite Al/O-WTR during P capturing from agro- wastewaters; and 3) critically evaluate the performance of the composite Al/O-WTR as a fertilizer using selected plants grown in lysimeters and test-field studies. Instead of lysimeters we used pots (Israel) and one- liter cone-tainers (USA). We conducted one field study but in spite of major pretreatments the soils still exhibited high enough P from previous experiments so no differences between control and P additions were noticeable. Due to time constrains the field study was discontinued. Background: Phosphorous, a non-renewable resource, has been applied extensively in fields to increase crop yield, yet consequently has increased the potential of waterway eutrophication. Our proposal impetus is the need to develop an innovative method of P capturing, recycling and reuse that will sustain agricultural productivity while concurrently reducing the level of P discharge from and to agricultural settings. Major Conclusions & Achievements: An innovative approach was developed for P removal from soil leachate, dairy wastewater (Israel), and swine effluents (USA) using Al-based water treatment residuals (Al- WTR) to create an organic-Al-WTR composite (Al/O-WTR), potentially capable of serving as a P fertilizer source. The Al-WTR removed 95% inorganic-P, 80% to 99.9% organic P, and over 60% dissolved organic carbon from the agro-industrial waste streams. Organic C accumulation on particles surfaces possibly enhanced weak P bonding and facilitated P desorption. Analysis by scanning electron microscope (SEM- EDS), indicated that P was sparsely sorbed on both calcic and Al (hydr)oxide surfaces. Sorption of P onto WW-Al/O-WTR was reversible due to weak Ca-P and Al-P bonds induced by the slight alkaline nature and in the presence of organic moieties. Synchrotron-based microfocused X-ray fluorescence (micro-XRF) spectrometry, bulk P K-edge X-ray absorption near edge structure spectroscopy (XANES), and P K-edge micro-XANES spectroscopy indicated that adsorption was the primary P retention mechanism in the Al- WTR materials. However, distinct apatite- or octocalciumphosphatelike P grains were also observed. Synchrotron micro-XRF mapping further suggested that exposure of the aggregate exteriors to wastewater caused P to diffuse into the porous Al-WTR aggregates. Organic P species were not explicitly identified via P K-edge XANES despite high organic matter content, suggesting that organic P may have been predominantly associated with mineral surfaces. In screen houses experiments (Israel) we showed that the highest additions of Al/O-WTR (5 and 7 g kg⁻¹) produced the highest lettuce (Lactuca sativa L. var. longifolial) yield. Lettuce yield and P concentration were similar across treatments, indicating that Al/O- WTR can provide sufficient P to perform similarly to common fertilizers. A greenhouse study (USA) was utilized to compare increasing rates of swine wastewater derived Al/O-WTR and inorganic P fertilizer (both applied at 33.6, 67.3, and 134.5 kg P₂O₅ ha⁻¹) to supply plant-available P to spring wheat (TriticumaestivumL.) in either sandy loam or sandy clay loam soil. Spring wheat straw and grain P uptake were comparable across all treatments in the sandy loam, while Al/O-WTR application to the sandy clay loam reduced straw and grain P uptake. The Al/O-WTR did not affect soil organic P concentrations, but did increase phosphatase activity in both soils; this suggests that Al/O-WTR application stimulated microorganisms and enhance the extent to which microbial communities can mineralize Al/O-WTR-bound organic P. Implications: Overall, results suggest that creating a new P fertilizer from Al-WTR and agro-industrial waste sources may be a feasible alternative to mining inorganic P fertilizer sources, while protecting the environment from unnecessary waste disposal.
4
Caritat, P. de, e U. Troitzsch. Towards a regolith mineralogy map of the Australian continent: a feasibility study in the Darling-Curnamona-Delamerian region. Geoscience Australia, 2021. http://dx.doi.org/10.11636/record.2021.035.
Testo completoAbstract (sommario):
Bulk quantitative mineralogy of regolith is a useful indicator of lithological precursor (protolith), degree of weathering, and soil properties affecting various potential landuse decisions. To date, no national-scale maps of regolith mineralogy are available in Australia. Catchment outlet sediments collected over 80% of the continent as part of the National Geochemical Survey of Australia (NGSA) afford a unique opportunity to rapidly and cost-effectively determine regolith mineralogy using the archived sample material. This report releases mineralogical data and metadata obtained as part of a feasibility study in a selected pilot area for such a national regolith mineralogy database and atlas. The area chosen for this study is within the Darling-Curnamona-Delamerian (DCD) region of southeastern Australia. The DCD region was selected as a ‘deep-dive’ data acquisition and analysis by the Exploration for the Future (2020-2024) federal government initiative managed at Geoscience Australia. One hundred NGSA sites from the DCD region were prepared for X-Ray Diffraction (XRD) analysis, which consisted of qualitative mineral identification of the bulk samples (i.e., ‘major’ minerals), qualitative clay mineral identification of the <2 µm grain-size fraction, and quantitative analysis of both ‘major’ and clay minerals of the bulk sample. The identified mineral phases were quartz, plagioclase, K-feldspar, calcite, dolomite, gypsum, halite, hematite, goethite, rutile, zeolite, amphibole, talc, kaolinite, illite (including muscovite and biotite), palygorskite (including interstratified illite-smectite and vermiculite), smectite (including interstratified illite-smectite), vermiculite, and chlorite. Poorly diffracting material (PDM) was also quantified and reported as ‘amorphous’. Mineral identification relied on the EVA® software, whilst quantification was performed using Siroquant®. Resulting mineral abundances are reported with a Chi-squared goodness-of-fit between the actual diffractogram and a modelled diffractogram for each sample, as well as an estimated standard error (esd) measurement of uncertainty for each mineral phase quantified. Sensitivity down to 0.1 wt% (weight percent) was achieved, with any mineral detection below that threshold reported as ‘trace’. Although detailed interpretation of the mineralogical data is outside the remit of the present data release, preliminary observations of mineral abundance patterns suggest a strong link to geology, including proximity to fresh bedrock, weathering during sediment transport, and robust relationships between mineralogy and geochemistry. The mineralogical data generated by this study are presented in Appendix A of this report and are downloadable as a .csv file. Mineral abundance or presence/absence maps are shown in Appendices B and C to document regional mineralogical patterns.