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Articoli di riviste sul tema "Soils Phosphorus content"
1
Weaver, DM, GSP Ritchie e RJ Gilkes. "Phosphorus sorption by gravels in lateritic soils". Soil Research 30, n. 3 (1992): 319. http://dx.doi.org/10.1071/sr9920319.
Testo completoAbstract (sommario):
The effect of sesquioxidic gravels (>2 mm size fraction) on phosphorus sorption by two gravelly lateritic soils was investigated by phosphorus sorption experiments, X-ray diffraction, autoradiography and electron microscopy.In one soil the abundance and size of gravels decreased downslope. As the gravel content of both soils increased (13-61%), the proportion of large (>8 mm) gravels increased (0-70%). Phosphorus sorption increased in the order: (>2 mm fraction) < (whole soils) < (<2 mm fraction). Phosphorus sorption on lateritic gravels (>2 mm) decreased with increasing gravel size and increased with increasing time. Phosphorus sorption by whole soils decreased with increasing gravel content. Phosphorus sorption by the >2 mm fraction was principally by the external surfaces of the gravels. The estimation of phosphorus application rates for lateritic soils depended on the amount of phosphorus required by the plant and the gravel content of the soil. The former is the important factor at low soil gravel contents whereas the latter becomes more important as the gravel content increases. The implications for fertilizer management on the soil with consistent relationships between landscape position, gravel content and subsequent P sorption properties of whole soils are discussed.
2
Gopp, N. V., O. A. Savenkov, T. V. Nechaeva, N. V. Smirnova e A. V. Smirnov. "Using of NDVI in digital mapping of phosphorus content in soils and assessment of it's availability by plants". Исследования Земли из Космоса, n. 2 (21 maggio 2019): 65–73. http://dx.doi.org/10.31857/s0205-96142019265-73.
Testo completoAbstract (sommario):
It was developed а method of digital mapping of phosphorus content (total, organic, available) in soils using spatially distributed NDVI values calculated from Landsat 8 (30 m resolution). It was carried out comparative analysis of content of phosphorus of soils differing in soil humus content: with high and medium humus content. In medium-humus soils (agrochernozems, agro-dark-grey) compared to high- humus agrochernozems discovered lower contents of total phosphorus in 1.1 times, and organic phosphorus in 1.5–1.7 times. The reverse trend was found for available phosphorus — in all medium- humus soils its content was more in 2 times as compared with high-humus agrochernozems. The provision of plants with phosphorus was sufficient, since its content in the above-ground phytomass of the oat-pea mixture was in the optimal range of 0.23–0.5% for a completely dry mass. According to the visual diagnostics of external signs of phosphorus deficiency in plants was not revealed. It was not found correlation between the content of phosphorus in plants, the reserves of above-ground phytomass of oat-pea mixture and NDVI.
3
Gabriela, Mühlbachová, Čermák Pavel, Vavera Radek, Káš Martin, Pechová Miroslava, Marková Kateřina, Kusá Helena, Růžek Pavel, Hlušek Jaroslav e Lošák Tomáš. "Boron availability and uptake under increasing phosphorus rates in a pot experiment". Plant, Soil and Environment 63, No. 11 (20 novembre 2017): 483–90. http://dx.doi.org/10.17221/480/2017-pse.
Testo completoAbstract (sommario):
The boron (B) availability in soils, B uptake and possible B interactions with phosphorus (P) were studied in a pot experiment with increasing P rates. Three soil types of different characteristics were used for the experiment that lasted two years. The two soil tests were used in the experiment – Mehlich 3 and NH<sub>4</sub>-acetate. Significant positive correlations were found between barley dry matter yield, B content in plants and B uptake under increasing P treatments (P ≤ 0.001). The significant relationship for B content (P ≤ 0.001) was obtained between the used soil tests for all tested soils. A decrease of soil B content in soils under increasing P doses was determined. NH<sub>4</sub>-acetate soil test showed a significant relationship between B and P contents (P ≤ 0.001) within the studied soils in comparison with the Mehlich 3 method. Considering individual soils, the NH<sub>4</sub>-acetate test showed more often higher significance in comparison with the Mehlich 3 test. The interactions between P and B in soils should be taken in consideration when deciding about the phosphorus fertilization.
4
Rogeri, Douglas Antonio, Leandro Bortolon, Clesio Gianello e Magno Batista Amorim. "Remaining phosphorus content to determine phosphorus availability of the soils in Rio Grande do Sul". Pesquisa Agropecuária Brasileira 52, n. 12 (dicembre 2017): 1203–14. http://dx.doi.org/10.1590/s0100-204x2017001200009.
Testo completoAbstract (sommario):
Abstract: The objective of this work was to evaluate remaining P compared with soil clay content as a P buffer index to classify P extracted by the Mehlich-1 (M1) and Mehlich-3 (M3) methods in soils from the state of Rio Grande do Sul, Brazil. The experiment was carried out in a completely randomized design with five P2O5 rates (0, 50, 100, 200, and 400 mg kg-1) and two sucessive corn crops, and three replicates, in 20 representative soils of the state. P extracted by M1 and M3 before crop planting was adjusted to P contents in biomass, considering soil buffer capacity. The division of soils into different buffering classes, based on soil clay or remaining P, improved the capacity of estimating soil available P of both methods. However, there was no difference among the correlation coefficients obtained by classifying soils according to the evaluated indexes (remaining P or soil clay) for both M1 and M3 methods. Remaining P is a viable alternative to replace soil clay content to classify soil P extracted with the M1 and M3 methods.
5
Sánchez-Esteva, Sara, Maria Knadel, Rodrigo Labouriau, Gitte H. Rubæk e Goswin Heckrath. "Total Phosphorus Determination in Soils Using Laser-Induced Breakdown Spectroscopy: Evaluating Different Sources of Matrix Effects". Applied Spectroscopy 75, n. 1 (24 agosto 2020): 22–33. http://dx.doi.org/10.1177/0003702820949560.
Testo completoAbstract (sommario):
Laser-induced breakdown spectroscopy (LIBS) is a potential alternative to wet chemical methods for total soil phosphorus determination, but matrix effects related to physical and chemical sample properties need to be further understood. The aim of this study was to explore matrix effects linked to particle size distribution and chemical form of phosphorus on LIBS response and the ability of LIBS to predict total phosphorus in a range of different soil types. Univariate calibration curves were developed by spiking the soils with increasing doses of phosphorus, and limits of detection for LIBS determined phosphorous (P) (LIBS-P) were calculated. Different particle size distributions in otherwise identical soils were obtained by four milling treatments and effects of chemical form of phosphorus were examined by spiking soils with identical amounts of phosphorus in different chemical compounds. The LIBS-P response showed a high correlation (R2 > 0.99) with total phosphorus for all soils. Yet, the sensitivity of LIBS differed significantly among soils, as the slope of the calibration curves increased with increasing sand content, resulting in estimated limits of detection of 10 mg kg−1 for the sandiest and 122 mg · kg−1 for the most clayey soils. These limits indicate that quantitative evaluation of total phosphorus in sandy and loamy sandy soils by LIBS is feasible, since they are lower than typical total phosphorus concentrations in soil. A given milling treatment created different particle size distributions depending on soil type, and consequently different LIBS-P results. Thus, procedures that specify the required degree of homogenization of soil samples prior to analysis are needed. Sieving after milling could be an option, but that should be tested. The soils spiked with Fe(III) phosphate, potassium phosphate and phytic acid had similar LIBS-P, except for soils with hydroxyapatite, which resulted in markedly lower response. These results suggested that matrix effects related to the chemical nature of phosphorus would be minor for non-calcareous soils in humid regions, where apatites comprise only a small fraction of total phosphorus. Strategies to overcome matrix effects related to particle size and content of apatite-phosphorus by combining multivariate models and soil type groupings should be further investigated.
6
Minina, N. N., A. R. Makhmutov e O. V. Sinelnikova. "Agrochemical characteristics of soils in the vicinity of the village of Mishkino, Mishkinsky district of the Republic of Bashkortostan". IOP Conference Series: Earth and Environmental Science 1043, n. 1 (1 giugno 2022): 012053. http://dx.doi.org/10.1088/1755-1315/1043/1/012053.
Testo completoAbstract (sommario):
Abstract The article is devoted to the analysis of the dynamics of the content of such important elements of fertility as phosphorus and potassium and the acidity of arable soils in the vicinity of the Mishkino Mishkinsky district of the Republic of Bashkortostan is determined. The data on the content of phosphorus and potassium and the determination of acidity in the soils of the Mishkinsky district of the Republic of Bashkortostan from 1976 to 2000 were compared. Studies on the phosphorus content in the soils of the Mishkino district conducted in 1976 showed an average level of phosphorus availability. Studies conducted in 1992 showed a slight increase in the availability of phosphorus in the soil. Studies in 2015 and 2020 showed a continuing trend of increasing the availability of phosphorus in the soil. Studies conducted to study the potassium content showed a fairly low potassium content in 1976. In 1992, in general, there were changes in the classes of security and in the amount of potassium content in the soil. Studies in 2015 and 2020 showed a steady trend towards an increase in potassium content in the soils of the district and the presence of soils only with an increased and high potassium content. Studies on soil acidity conducted in 1976 showed that the area of arable soils is mainly represented by medium-acid and slightly acidic soils. Studies in 1992 showed an increase in soil acidity. In the following years, the farm undertook methods of agrochemical effects on soils in order to reduce acidity. Research 2015. and 2020 showed a significant decrease in the acidity of arable soils. It has been established that due to the use of methods of rational nature management of territories, the area of agricultural soils with an average and increased content of mobile phosphorus and exchangeable potassium increases, processes of neutralization of strongly acidic soils occur.
7
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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Olego, Miguel Ángel, Mateo D. Cuesta-Lasso, Fernando Visconti Reluy, Roberto López, Alba López-Losada e Enrique Garzón-Jimeno. "Laboratory Extractions of Soil Phosphorus Do Not Reflect the Fact That Liming Increases Rye Phosphorus Content and Yield in an Acidic Soil". Plants 11, n. 21 (27 ottobre 2022): 2871. http://dx.doi.org/10.3390/plants11212871.
Testo completoAbstract (sommario):
In addition to aluminum and other heavy metal toxicities, acidic soils also feature nutrient deficits that are not easily overcome by merely adding the required amounts of mineral fertilizers. One of the most critically scarce nutrients in acidic soils is phosphorus, which reacts with aluminum and iron to form phosphates that keep soil phosphorus availability significantly low. Liming ameliorates acidic soils by increasing pH and decreasing aluminum contents; however, it also increases the amount of calcium, which can react with phosphorus to form low-solubility phosphates. In the present work, three liming materials, namely, dolomitic limestone, limestone and sugar foam, were applied on a Typic Palexerult cropped with rye. The effects of these materials on soil properties, including soil available phosphorus extracted with the Olsen and Bray-1 methods, rye phosphorus content in stems and stem and spike harvested biomasses were monitored for nine years. According to the Olsen extraction, the amount of soil available phosphorus generally decreased following liming, with limestone presenting the lowest values; however, the amount of soil available phosphorus increased according to the Bray-1 extraction, though only to a significant extent with the sugar foam from the third year onward. Regardless, the phosphorus content in rye and the relative biomass yield in both stems and spikes generally increased as a consequence of liming. Since crop uptake and growth are the ultimate tests of soil nutrient availability, the inconsistent stem phosphorus content results following the Olsen and Bray-1 extraction methods suggest a lowered efficiency of both extractants regarding crops in soils rich in both aluminum and calcium ions. This decrease can lead to important interpretation errors in the specific conditions of these limed acidic soils, so other methods should be applied and/or researched to better mimic the crop roots’ phosphorus extraction ability. Consequently, the effects of the liming of acidic soils on phosphorus availability and crop performance in the short and long term will be better understood.
9
Xu, G., J. N. Sun, R. F. Xu, Y. C. Lv, H. B. Shao, K. Yan, L. H. Zhang e M. S. A. Blackwell. "Effects of air-drying and freezing on phosphorus fractions in soils with different organic matter contents". Plant, Soil and Environment 57, No. 5 (16 maggio 2011): 228–34. http://dx.doi.org/10.17221/428/2010-pse.
Testo completoAbstract (sommario):
Little is known about the effects of air-drying and freezing on the transformation of phosphorus (P) fractions in soils. It is important that the way in which soils respond to such perturbations is better understood as there are implications for both P availability and loss to surface waters from soils. In this study, the effects of air-drying and freezing were investigated using two soils, one being a forest soil (FS) high in organic matter and the other being a sterile soil (SS) low in organic matter. Soil P was fractionated using a modified Hedley fractionation method to examine the changes of phosphorus fractions induced by air-drying and freezing. Generally, there were no significant differences of total phosphorus among the three treatments (CV% < 10%). Compared with field moist soils, freezing the soil evoked few changes on phosphorus fractions except that the resin-P increased in FS soil. On the contrary, air-drying significantly changed the distribution of phosphors fractions for both soils: increased the labile-P (especially resin-P) and organic-P (NaHCO<sub>3</sub>-Po, NaOH-Po and Con.HCl-Po) at the expense of NaOH-Pi and occlude-P (Dil.HCl-P and Con.HCl-Pi). Resin-P significantly increased by 31% for SS soil and by 121% for FS soil upon air-drying. The effect of air-drying seemed to be more pronounced in the FS soil with high organic matter content. These results indicated that drying seem to drive the P transformation form occlude-P to labile-P and organic-P and accelerated the weathering of stable P pool. This potentially could be significant for soil P supply to plants and P losses from soils to surface waters under changing patterns of rainfall and temperature as predicted by some climate change scenarios.
10
Chowdhury, S., D. Chakraborty e MK Rahman. "Assessment of fertility potential index of some soils of Moheshkhali betel leaf (Piper betle L.) estate". Journal of Biodiversity Conservation and Bioresource Management 7, n. 1 (10 gennaio 2022): 25–32. http://dx.doi.org/10.3329/jbcbm.v7i1.57120.
Testo completoAbstract (sommario):
Fifteen soil samples (0-15cm depth) and fifteen betel leaf samples from Bara Moheshkhali, Choto Moheshkhali, Hoanak, Kalmarchora, Shaplapur union of Moheshkhali upazila, Cox’s Bazar district were collected on December-January (2020-2021). It was collected for the purpose of evaluating the color, particle density, moisture content, texture, pH, EC and organic matter content of soils and total nitrogen, phosphorous, potassium and sulfur of the soils and total protein content, nitrogen, phosphorus, potassium and sulfur of leaves. Maximum sampled soil was containing yellowish red color when moist and showed brown color when dried. Some of them were flood plain soil and that’s why showed grey color during dry and moist condition. Mean particle density was 2.49 g/cm3 and mean moisture content was 13.95%. Average sand, silt and clay were 65.08%, 18.56% and 19.26%, respectively. The texture of the soils was sandy loam to clay loam. The sand was by far the dominant fraction in the soils. Mean pH value was 5.63, organic matter was 0.30% and EC was 99.38μS/cm. Mean total nitrogen, phosphorus, potassium and sulfur of the soils were 0.04, 0.46, 0.25 and 0.26%, respectively. The mean concentration of protein, nitrogen, phosphorus, potassium and sulfur in the betel leaf samples were 20.56, 3.29, 0.39, 0.79 and 0.20%, respectively. This investigation focuses on the fertility status and physico-chemical properties of soil in betel leaf garden of only hilly island of Bangladesh, Moheshkhali. J. Biodivers. Conserv. Bioresour. Manag. 2021, 7(1): 25-32
Tesi sul tema "Soils Phosphorus content"
1
Zhang, Tiequan. "Chemical behavior of phosphorus over time in fertilized soils". Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=34486.
Testo completoAbstract (sommario):
Fertilizer P accumulates in soils, with potential for movement to waterways, causing eutrophication. Fertilizer P reactions in monoculture corn (Zea mays L.) production over time will determine environmentally sound soil management practices. Soil P changes over time were determined on a Chicot sandy clay loam (Grey Brown Luvisol) and a Ste. Rosalie clay (Humic Gleysol). Fertilizer P was added at 44 and 132 kg P ha$ sp{-1}$ and to the Chicot soil only, manure containing 60 kg P for the first five years. Mehlich-3 (M3) extraction, soil P fractionation, $ sp{31}$P NMR analysis, P in leaching water, and path analysis were measured. Added P increased M3 P more when manure was also added, and in clay soils. To increase M3 P by 1 kg ha$ sp{-1}$ required from 3.6 to 8.1 kg ha$ sp{-1}$ fertilizer P, and when "net" fertilizer additions were used, fertilizer required was from 1.8 to 5.3 kg P ha$ sp{-1}.$ Moderately labile organic P (Po) decreased at 0 added P. With P at the rate of plant removal, inorganic (Pi) and Po fractions were unchanged. Excess P increased labile P and resistant P through moderately labile Pi. More P remained in labile Pi fractions when manure P was added, or in the soil with the higher clay content. Soil organic P levels increased upon fertilization only in the sandy loam soil. Labile and moderately labile Po could be estimated using monoester phosphate values determined by $ sp{31}$P NMR. Inorganic P values in gravitational water increased above 0.05 mg P L$ sp{-1}$ when soil labile Pi increased above 108 mg kg$ sp{-1}$ in the sandy loam soil and 69 mg L$ sp{-1}$ in the clay soil. Thus soil P movement was related to inorganic P additions. Increased fertilizer P did not increase organic P leaching losses. Fertilizer P in corn production may result in groundwater eutrophication.
2
Abou, Nahra Joumana. "Modeling phosphorus transport in soil and water". Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=102946.
Testo completoAbstract (sommario):
The main objective of this project was to investigate and model phosphorus (P) transport in soil column studies. A model named HYDRUS-NICA was developed, by coupling a hydrological and transport model (HYDRUS-1D model) with an aqueous chemical model (non-ideal competitive adsorption - NICA), to improve the predictions of P transport in soil and water. The HYDRUS-NICA model was developed by replacing the non-linear empirical (Freundlich and Langmuir) equations of the HYDRUS-1D model with the NICA model equations. The numerical accuracy of the HYDRUS-NICA model was then evaluated by comparing the relative errors produced by the HYDRUS-NICA and HYDRUS-1D models. The results showed that the numerical schemes of the HYDRUS-NICA code are stable.The ability of the NICA model to describe phosphate (PO4) adsorption to soil particles was tested using soils collected from agricultural fields in southern Quebec. The surface charge and PO4 adsorption capacity of these soils were measured. Results were used to estimate the NICA model parameters using a non-linear fitting function. The NICA model accurately described the surface charge of these soils and the PO4 adsorption processes.
The HYDRUS-1D model was applied to simulate water flow and PO4 transport in re-constructed soil column experiments. The HYDRUS-1D model was calibrated based on physical and chemical parameters that were estimated from different experiments. Overall, the HYDRUS-1D model successfully simulated the water flow in the columns; however, it overestimated the final adsorbed PO4 concentrations in the soil. The discrepancies in the results suggested that the HYDRUS-1D model could not account for the differences in the soil structure found in the columns, or that the Freundlich isotherm could not adequately describe PO4 adsorption.
The HYDRUS-NICA model was calibrated and validated with results from re-packed column experiments. The simulated results were then compared with results obtained by the HYDRUS-1D model. The overall goodness-of-fit for the HYDRUS-1D model simulations was classified as poor. The HYDRUS-NICA model improved significantly the prediction of PO4 transport, with the coefficient of modeling efficiency values being close to unity, and the coefficient of residual mass values being close to zero. The HYDRUS-NICA model can be used as a tool to improve the prediction of PO4 transport at the field scale.
3
Gichangi, Elias Maina. "Enhancing phosphorus availability in some phosphate fixing soils of the Transkei region, South Africa using goat manure". Thesis, University of Fort Hare, 2007. http://hdl.handle.net/10353/80.
Testo completoAbstract (sommario):
Low availability of soil phosphorus (P) caused by strong sorption of P is a major constraint to agricultural production in most South African soils, particularly those from the high rainfall areas. The aim of this study was therefore to investigate whether combined addition of goat manure with inorganic P fertilizers could enhance P availability in some P fixing soils of the Transkei region, South Africa. The study addressed the following specific objectives (i) to assess P sorption capacities and requirements of selected soils and their relationship with selected soil properties and single point sorption test, (ii) to assess the effects of goat manure and lime addition on P sorption properties of selected P fixing soils (iii) to assess the temporal changes in concentration of inorganic and microbial biomass P fractions following application of inorganic fertilizer P with goat manure in a laboratory incubation experiment, and, (iv) to assess the effects of goat manure application with inorganic phosphate on inorganic and microbial biomass P fractions, P uptake and dry matter yield of maize. Sorption maxima (Smax) of seven soils examined ranged from 192.3 to 909.1 (mg P kg-1) and were highly and positively correlated with sorption affinity constant (r = 0.93, p = 0.01) and organic C (r = 0.71, p = 0.01). The amount of P required for maintaining a soil solution concentration of 0.2 mg P l-1 ranged from 2.1 to 123.5 mg P kg-1 soil. Soils collected from Qweqwe (a Cambisol), Qunu (an Acrisol), Ncihane (a Luvisol) and Bethania (a Ferralsol) had lower external P requirement values and were classified as lower sorbers, whereas soils from Ntlonyana (a Planosol), Chevy Chase (a Ferralsol) and Flagstaff (a Ferralsol) were classified as moderate sorbers. The results suggested that P availability could be compromised in 43 percent iii of the soils studied and that measures to mitigate the adverse effects of P sorption were needed to ensure that P is not a limiting factor to crop production, where such soils are found. Goat manure addition at varying rates (5, 10 and 20 tha-1 dry weight basis) to two of the moderately P fixing soils from Chevy Chase and Flagstaff, reduced P sorption maxima (Smax) compared to the control treatment. Phosphate sorption decreased with increasing amounts of goat manure in both soils but the extent of reduction was greater on Chevy Chase soil than on Flagstaff soil. The relative liming effects of the different rates of goat manure followed the order 20 t GM ha-1 > 10 t GM ha-1 > 5 t GM ha-1. In a separate experiment, addition of inorganic P at varying rates (0, 90, 180, and 360 kg P ha-1) to Flagstaff soil increased labile P fractions (resin P, biomass P and NaHCO3-Pi) and the increases were greater when goat manure was co-applied. The control treatments contained only 17.2 and 27.5 mg P kg-1 of resin extractable P in the un-amended and manure amended treatments, respectively which increased to 118.2 and 122.7 mg P kg-1 on day 28 of incubation. Biomass P concentration was increased from 16.8 to 43.9 mg P kg-1 in P alone treatments but the fraction was greatly enhanced with manure addition, increasing it from 32.6 to 97.7 mg P kg-1. NaOH-Pi was the largest extractable Pi fraction and ranged from 144.3 to 250.6 mg P kg-1 and 107.5 to 213.2 mg P kg-1 in the unamended and manure amended treatments, respectively. Dry matter yield and P uptake by maize grown in the glasshouse were highly and significantly (p = 0.05) correlated with the different P fractions in the soil. The correlations followed the order resin P (r = 0.85) > NaOH-Pi (r = 0.85) > NaHCO3-Pi (r = 0.84) >> biomass P (r = 0.56) for dry matter yield at 6 weeks after planting. At 12 weeks after planting, goat manure had iv highly significant effects on resin P and biomass P but had no effect on NaHCO3-Pi and NaOH–Pi. The combination of biomass P, resin P and NaHCO3-Pi explained 75.8 percent of the variation in dry matter yield of which 63.0 percent of the variation was explained by biomass P alone. The greatest increase in biomass P occurred when added P was co-applied with 5 or 10 tha-1 goat manure. The predictive equation for maize dry matter yield (DM) was: DM (g) = 1.897 biomass P + 0.645 resin P (r = 0.73). Resin P was the fraction that was most depleted due to plant uptake and decreased by 56 to 68 percent between the 6th week and the 12th week of sampling indicating that it played a greater role in supplying plant available P. The results therefore suggested that the use of goat manure may allow resource poor farmers to use lower levels of commercial phosphate fertilizers because of its effect to reduce soil P sorption. In addition, higher increases in biomass P due to manure addition observed at lower rates of added P indicated that goat manure has potential for enhancing bioavailability and fertilizer use efficiency of small inorganic P applications.
4
Leung, Miu-fun, e 梁妙芬. "Persistence of {221}-propeller phytase in soil and its implication in phosphorus mobilization". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B30736511.
Testo completo
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Stewart, Lynda Irene. "Phosphorus effects on arbuscular mycorrhizal fungi". Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=102729.
Testo completoAbstract (sommario):
Two field studies were conducted to assess the potential benefit of arbuscular mycorrhizal (AM) inoculation of elite strawberry plants on plant multiplication, and fruit yield, under typical nursery conditions, in particular soils classified as excessively rich in P. To study plant productivity, five commercially in vitro propagated elite strawberry cultivars ('Chambly', 'Glooscap', 'Joliette', 'Kent', and 'Sweet Charlie') were not inoculated with AM fungi or were inoculated with either a single species (Glomus intraradices), or a mixture of species (G. intraradices, Glomus mosseae, and Glomus etunicatum). AM inoculation was found to impact strawberry plant productivity in a soil with excessive P levels. The AM fungi introduced into the field by inoculated mother plants established a mycelial network in the soil through colonization of the daughter plant roots, however, persistence of colonization was determined to below (<12% in inoculated plant roots). In soils excessively rich in P, individual crop inoculation may be the only option for management of the symbiosis, as the host and non-host rotation crops, planted prior to strawberry production, had no effect on plant productivity or soil mycorrhizal potential.To study the impact of AM inoculation on fruit production, three commercially grown strawberry cultivars (Glooscap, Joliette, and Kent) were not inoculated with AM fungi or were inoculated with either G. intraradices or G. mosseae. AM fungi impacted the fruit yield, with all inoculated cultivars producing more fruit than noninoculated cultivars during the first harvest year. The percentage of root colonization could not be used to explain the differences in total fruit yield during the first harvest year, or the increase in total fruit yield the second harvest year.
We wished to examine the effects of various P treatments on C metabolism within the intraradical mycelia (IRM) of the fungus. Specific primers were developed for the Glomus intraradices glucose-6-phosphate dehydrogenase (G6PDH) gene. Real-time quantitative reverse transcriptase polymerase chain reaction (QRT-PCR) was used to measure the gene expression of the G. intrarardices G6PDH gene in response to external P conditions of colonized transformed carrot roots. The results showed a significant down-regulation of G6PDH in the IRM of G. intraradices when cultures were grown in a high P (350 muM P) medium compared to those grown in the low P (35 muM P) medium. The down-regulation may suggest a reduction in the C flow from the host to the fungus. There was no effect on G6PDH expression following a two-hour incubation with additional P applications (No P, low P and high P).
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Croat, Samantha Jo. "Phosphorus Dynamics and Crop Productivity in Bakken Crude-Oil Remediated Soils". Thesis, North Dakota State University, 2018. https://hdl.handle.net/10365/29169.
Testo completoAbstract (sommario):
Thermal desorption (TD), a remediation method used to remove hydrocarbons from contaminated soils, may cause changes in soil properties that threaten soil function and plant productivity. The goal of this research is to better understand the effect that TD treatment has on soils intended for agricultural use. A series of soil phosphorus (P) sorption and desorption experiments were conducted on soils before and after TD treatment to determine P availability for plant uptake and risk for run-off. TD-treated soils retained more P, likely due to mineral transformations of Fe- and Al-oxides. In addition, a three-year field study using mixtures of topsoil (A), crude-contaminated soil (SP), and TD-treated soils (TDU) was conducted. Yields were significantly greater in plots that included A in the mixture compared to SP and TDU soils alone. TD-treated soils can be a replacement for topsoil, but the addition of topsoil will reduce the time to successful reclamation.
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A, Heskett Richard. "Determining soil phosphorus concentrations using cattail indicators". Virtual Press, 1997. http://liblink.bsu.edu/uhtbin/catkey/1048396.
Testo completoAbstract (sommario):
Excess phosphorus is often identified as a major factor in the eutrophication of wetlands and lakes. Often attributed to agricultural practices, the specific source of a large part of this excess has been difficult to determine. The term "nonpoint" source is often used to broadly describe the inflow along waterways of significant amounts of this essential plant nutrient and other pollution. This research was intended to determine the effectiveness of using cattails (Typha), a common plant along waterways, as indicators of plant available phosphorus in the soil along these waterways. Two sites in the southern part of Michigan's lower peninsula (45°N,84°W) where cattails grew were systematically examined for phosphorus and certain cattail characteristics. Plant and soil data were gathered in a grid-like pattern to determine both the relationship of paired data and their spatial distribution across each site. One set of data was shown to be significant. At one site, the density of cattails is weakly correlated with Phosphorus concentrations. Of particular importance, the spatial distribution of both variables is also noticeably similar at the site. No significant correlation between other data was shown. There is also no apparent similarity in spatial distribution. Though weakly correlated, we were able to support a hypothesis that a reasonable correlation exists between cattail density and plant available phosphorus at one site. The spatial distribution of these traits are also similar suggesting that cattails may, in some cases, be useful as indicators of excess phosphorus, perhaps better defining its source than “nonprint”.Department of Biology
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Kathuli, Peter. "The effects of 40 years of cultivation on organic phosphorus in a highly organic soil of south western British Columbia". Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/29034.
Testo completoAbstract (sommario):
The effects of 40 years of integrated field management on soil organic phosphorus and its forms was evaluated on a highly organic B.C. soil supporting high value vegetable crops. This project was undertaken to study the effects of cultivation on the soil content of organic phosphorus, as a predictor of overall degradation effects of the soil organic matter. Organic carbon, total nitrogen, soil pH and total and inorganic phosphorus were also evaluated, due to the strong relationship of organic P and these other soil chemical properties. The forms of organic P that were evaluated were the phytic acid, inositol polyphosphates and the soil biomass phosphorus.
The biomass P was used as a predictor of the effects of cultivation on nucleic acids since the soil methods for nucleic acid determination were very complicated and time consuming.
In this study, attempts were made to find a shorter soil analytical method for phytic acid, the largest pool of soil organic phosphorus. Due to chemical structure of phytic acid and its higher negative charge, it was believed that this molecule is highly stable in the soil environment due to its adsorption and/or precipitation on mineral surfaces through cation bridging at low soil pH particularly by Iron and Aluminium salts and hydrous oxides which bear pH-dependent positive charge or through P chermsorption, and hence its turnover rate due to cultivation could be used to predict the behaviour of the rest of soil organic P and hence the organic matter in the same soil environment.
It was however realized that P analysis in soils was very cumbersome and there was a need for a shorter and precise quantitative analytical technique for this element in the soil. ³¹P NMR spectroscopy was thought to be the solution and its possibilities were evaluated in this project. Therefore the objectives of the study were;
a) To determine the effects of 40 yrs of integrated field managements on organic P and its forms.
b) To develop a shorter method for soil phytic acid analysis.
c) To attempt the use of ³¹P NMR for qualitative
and quantitative determinations of soil phytic acid.
It was found that soil pH was significantly increased from pH 4.46 to 5.28 due to liming and the increased degree of organic matter decomposition.
Total nitrogen was significantly decreased by 24% with larger significant decrease of 42% in the shallow organic cultivated soil site, and only 8% significant decrease in the highly organic, deeper cultivated soil site. The decline in soil nitrogen was attributed to mineralization of organic nitrogen followed by crop uptake and leaching losses.
Organic carbon was significantly decreased by 22%. There was a 40% decrease in this organic carbon in the cultivated shallow organic cultivated soil site, but there was no significant effect of cultivation on organic carbon (hence the organic matter) in the highly organic deeper cultivated soil site. There was no significant effect of cultivation on the C/N ratio. However, the highly organic deeper soil site had significantly wider C/N ratio than the shallow organic cultivated soil site. This observation was attributed to the degree of decomposition of soil organic matter in the two sites.
There was a significant 20% decrease in P total in the highly organic deeper cultivated soil site. There was no significant effect of cultivation on P total in the shallow organic cultivated soil site, however there were indications of 33% accumulation in total P in this soil site as determined by ignition method.
There was 179% accumulation of inorganic P in the shallow organic cultivated soil site, but there was no significant effect of cultivation on inorganic P in the deeper highly organic soil cultivated site.
Organic phosphorus was significantly decreased by 4 0 yrs of integrated field management by 31% on a soil basis and 25% on an ash free basis. The percentage of organic P in total soil P was significantly decreased from 66% to 45%. The C/orgnic P was increased significantly from 394 to 439. This reflected greater effects of cultivation on turnover of organic P than organic carbon in the organic matter and that P has a geological cycle which organic carbon does not have. The results further showed that before the field was placed under cultivation, the shallow organic soil site had a significantly larger amount (73%) of organic P in the soil total P. However cultivation had a significant decrease in organic P by 23% in the deeper highly organic soil cultivated site and 40% in the shallow organic cultivated soil site.
The study soil sites started with same the amounts of biomass P (the most labile form of organic P) , however it was found that 40 years of cultivation had no significant effects on this biomass in the highly organic soil site, but there was a significant decrease in biomass P by 86% in the shallow organic cultivated soil site.
Soil phytic acid, the largest pool of organic P was significantly decreased by 28% due to 40 yrs of integrated field management. Its turnover rate was found to be equal to the turnover rate of the other forms of organic P. It was however noted that the study soil sites started with same amount of phytic acid before the field was placed under cultivation. Phytic acid was significantly decreased due to cultivation in the shallow organic cultivated soil site by 35%, but there was no significant effect of cultivation on phytic acid in the highly organic cultivated soil site.
Inositol polyphosphates were not significantly affected by 40 years of integrated management. This form of organic P was found to have the same turnover rate as the rest of soil organic P. The slower turnover rate of inositol polyphosphates assayed by the barium acetate precipitation method of McKercher and Anderson was attributed to methodology.
In the present study, there were no significant differences in results obtained by various methods for total P determination except in a few cases where the ignition method was thought to have over-estimated total P.
A tentative new method for phytic acid analysis was developed in the on-going research. This method was proposed to be applicable in all soils. However, further research is required to confirm the purity of the phytic acid determined by this method.
³¹P NMR spectroscopy showed potential possibility for qualitative and quantitative analysis of soil phytic acid. However, it was emphasized that care should be exercised particularly during sample concentration step.
It was concluded that organic P and its forms, organic carbon, total nitrogen, soil pH and phytic acid were significantly decreased by 40 years of integrated field management more in the shallow organic cultivated soil sites than in the deeper highly organic soil sites. This observation was found very interesting and was in contrast to existing soil literature and further research was proposed in this direction to investigate this phenomenon.Land and Food Systems, Faculty of
Graduate
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Piper, Allison. "Root Length Affects Soluble Carbon and Phosphorus in a Rotational Cropping System". Fogler Library, University of Maine, 2005. http://www.library.umaine.edu/theses/pdf/PiperA2005.pdf.
Testo completo
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Ouyang, Duosheng. "New fertilizer combinations for improved nitrogen and phosphorus use efficiency and reduced environmental damage in corn production". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape15/PQDD_0004/NQ30353.pdf.
Testo completoLibri sul tema "Soils Phosphorus content"
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Menon, R. G. The Pi̳ soil phosphorus test: A new approach to testing for soil phosphorous. Muscle Shoals, Ala: International Fertilizer Development Center, 1989.
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Harrison, A. F. Soil organic phosphorus: A review of world literature. Wallingford, U.K: CAB International, 1987.
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Fosfornyĭ obmen u sosny na Severe. Petrozavodsk: Karelʹskiĭ filial AN SSSR, In-t lesa, 1989.
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Cihacek, L. J. Summary of soil fertility levels for North Dakota, 1991-2001. Fargo, N.D: NDSU Extension Service, 2009.
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A, Koshleva E., Churikov A. M e Evdokimova G. A, a cura di. Fosfor v podzolistykh pochvakh Kolʹskogo poluostrova. Apatity: Rossiĭskai͡a︡ akademii͡a︡ nauk, Kolʹskiĭ nauch. t͡s︡entr im. S.M. Kirova, 1992.
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Czępińska-Kamińska, Danuta. Wpływ procesów glebotwórczych na rozmieszczenie mineralnych związków fosforu w glebach. Warszawa: Wydawn. SGGW, 1992.
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Kuo, Shiou. Evaluation of four phosphorus soil tests and their relationship to corn yields for some western Washington soils. [Pullman]: Agriculture Research Center, College of Agriculture and Home Economics, Washington State University, 1985.
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Ohno, Tsutomu. Phosphorus and potassium availability in wood ash-amended soils: An incubation study. Orono, Me: Maine Agricultural and Forest Experiment Station, University of Maine, 1994.
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E, Strelʹchenko N., a cura di. Okislitelʹno-vosstanovitelʹnoe sostoi͡a︡nie pereuvlazhni͡a︡emykh pochv i transformat͡s︡ii͡a︡ nekotorykh ėlementov. Vladivostok: "Dalʹnauka", 1992.
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Magid, Jakob. Dynamics of phosphorus in sandy Danish soils. Denmark: Ministry of the Environment, National Environmental Research Institute, 1991.
Cerca il testo completoCapitoli di libri sul tema "Soils Phosphorus content"
1
Végh, K. R., G. Y. Füleky e T. Varró. "Phosphorus diffusion to barley (Hordeum vulgare) roots as influenced by moisture and phosphorus content of soils". In Plant Nutrition — Physiology and Applications, 147–51. Dordrecht: Springer Netherlands, 1990. http://dx.doi.org/10.1007/978-94-009-0585-6_25.
Testo completo
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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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Cortellini, L., G. Toderi, G. Baldoni e A. Nassisi. "Effects on the Content of Organic Matter, Nitrogen, Phosphorus and Heavy metals in Soil and Plants After Application of Compost and Sewage Sludge". In The Science of Composting, 457–68. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-009-1569-5_44.
Testo completo
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Ahmadi, Mirela, Ștefan A. Hulea e Ioan Peț. "Root Vegetables: Biology, Nutritional Value and Health Implications". In Root Vegetables [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.106240.
Testo completoAbstract (sommario):
Plants served as main staple for humanity since time immemorial. Plant roots science is a fascinating domain that offers a window to the complex world of plants-microorganisms relationship. Plant roots were used throughout human history both as a food source particularly in times of food scarcity as well as for medicinal purposes aid in the treatment of various human disorders. Root vegetables are excellent sources of fiber and antioxidants and are low in calories and lipids—being indispensable in human diet. There is an increasing interest in the biochemical processes occurring in the rhizosphere between root tissues and the bacterial/fungal colonizers especially in soils where there is a deficiency in minerals such as iron, phosphorus and selenium or there is higher load of toxic metals such as aluminum, cadmium, nickel and lead. That interest stems from the need to improve crop yields in hostile environmental conditions such as drought and low nutrient availability in soils. In this chapter, we will focus on the typical edible plant roots as well as bulbs (are not proper roots) looking at their nutrient content as well as their use as health enhancers.
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Kumar, Uttam, Nirmal Kumar, V. N. Mishra e R. K. Jena. "Soil Quality Assessment Using Analytic Hierarchy Process (AHP)". In Interdisciplinary Approaches to Information Systems and Software Engineering, 1–18. IGI Global, 2019. http://dx.doi.org/10.4018/978-1-5225-7784-3.ch001.
Testo completoAbstract (sommario):
Fields with rice-based cropping systems are unique from other wetland or upland soils because they are associated with frequent cycling between wetting and drying under anaerobic and aerobic conditions. This alters the C and N transformations, microbial activities and their diversity, and soil physical properties, depending on the other crop in rotation with rice. This chapter aims to compare the soil quality of vertisols of central plains of Chhattisgarh under rice-wheat and rice-chickpea cropping systems. Soil quality index was developed using analytical hierarchy process (AHP). Five soil quality indicators were selected under minimum datasets including soil organic carbon, mean weight diameter, available water content, available phosphorous and zinc. The results indicated that the rice-chickpea cropping system shows improved soil quality than that of rice-wheat cropping system.
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Tetsopgang, Samuel. "Increasing Yields and Soil Chemical Properties through the Application of Rock Fines in Tropical Soils in the Western Part of Cameroon, Africa". In Soil Contamination - Threats and Sustainable Solutions. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.93969.
Testo completoAbstract (sommario):
Local tropical soils were amended with pulverized rock fines such as trachyte, basalt, pyroclastic materials, limestone and gneiss with ± manure in different proportions in Cameroon. And soil textures and chemicals were assessed after harvesting. Cabbage and potatoes as test crops treated with fines of pyroclastic materials and basalts, portrayed highest and lowest productivities, respectively. The early loamy sand texture of controls changes to clay; and clay textures remained unchanged after treatments. This indicates the decrease of sand proportion and gain in clay particles after treatments. The pH of local soils was strongly to slightly acidic (4.8 ≤ pH ≤ 6.5) and rose up to slightly acidic and slightly alkaline affinity (6.6 ≤ pH ≤ 7.2). A significant pH increase from 5.9 to 6.9 was observed on a treated sample with pulverized pyroclastic materials. Organic carbon and Organic matter show parallel oscillated tendencies from controls to treated soils. There is a general increase of Mg and Ca after treatments while Na and K remain constant. Rock fines from trachyte, limestone and basalt as treatments significantly increase phosphorus in soils with contents of 96.0, 51.5 and 50.9 ppm, respectively.
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Tariq, Aqsa, e Ambreen Ahmed. "Phosphate Solubilizing Rhizobacteria as Sustainable Management Strategy in Agrobiology". In Environmental Sciences. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.108657.
Testo completoAbstract (sommario):
Phosphorous limits agricultural productivity due to its limited plant availability. Use of synthetic phosphate fertilizers disturbs soil fertility and ecosystem ecology as it contaminates environment. Plants have developed certain mechanisms to respond to P-scarcity, which involve release of specific chemical messengers through root exudates that attract rhizospheric phosphorbacteria to colonize plant root vicinity. Thus, use of phosphate-solubilizing bacteria/rhizobacteria (PSB/PSR) as biofertilizers is a safer approach toward sustainable agrobiology. These PSR are capable of solubilizing soil phosphate from insoluble to plant available form. Due to instability and slow movement of available phosphates in soils, they readily get incorporated with soil particles or chelates as metal complexes. In this scenario, PSR provide continuous chain of soluble phosphate to plants. PSR direct plant root system architecture toward available phosphate zones in soils. Moreover, there is an increased number of roots, root hair and lateral root, increase root absorbing surface area by increasing contact to soil particles. Hence, PSR-based root system morphology is a significant trait in measuring their agronomic efficiency. Moreover, PSB also possess phytostimulatory properties that significantly contribute to agricultural efficiency. Hence, the use of phosphate-solubilizing bacteria can improve crop productivity by increasing soil P-mobility and soil fertility.
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Olaleye, Adesola, Regina Mating, Tumelo Nkheloane, Tutu K. Samuel e Tolu Yetunde Akande. "Wetland Health in Two Agro-Ecological Zones of Lesotho: Soil Physico-Chemical Properties, Nutrient Dynamics and Vegetation Isotopic N15". In Soil Science - Emerging Technologies, Global Perspectives and Applications [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.101836.
Testo completoAbstract (sommario):
Monitoring is essential to evaluate the effects of wetland restoration projects. Assessments were carried-out after 6 years of restoration efforts on a wetland located in two agro-ecological zones (AEZ): the Mountains agro-ecological zone–Khalongla-lithunya (KHL) and the Foot Hills–Ha-Matela (HM). The former was under conservation and the latter non-conserved. Mini-pits were dug along transects for soil sampling. Runoff water was collected from installed piezometers into pre-rinsed plastic bottles with de-ionized water once a month for between 3 and 6 months. Soil and water samples were analyzed in the laboratory for Ca, Mg, K, Na, total nitrogen, and phosphorus, and soil samples were further analyzed for Cu, Fe, Zn, and Mn and vegetation isotopic N15. Water quality, soil organic matter (SOM), carbon pools, base cations, ratios (silt:clay & SOM:silt clay), texture, and N-15 isotopes were chosen as indicators. Results showed that base cations were significantly (p < 0.05) higher in the groundwater and soils of KHL wetlands compared with those from the HM. The soils of the KHL wetlands have higher (p < 0.05) clay, silt contents, SOM, and silt clay ratios compared with the HM. Furthermore, results of the N15 isotopes were between 2.52 and 2.93% (KHL) compared with 2.00 and 6.18% (HM). Similarly, the results of the δ13C showed significant negative values at KHL (28.13–28%) compared with HM (11.77–12.72%). The study concludes that after five years of rehabilitating the KHL wetlands, the soil indicators showed that restoration efforts are positive compared with the HM wetlands that are non-conserved.
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Tkachuk, Оlexander, e Nataliia Telekalo. "AGROECOLOGICAL POTENTIAL OF LEGUMES IN CONDITIONS OF INTENSIVE AGRICULTURE OF UKRAINE". In Integration of traditional and innovation processes of development of modern science. Publishing House “Baltija Publishing”, 2020. http://dx.doi.org/10.30525/978-9934-26-021-6-33.
Testo completoAbstract (sommario):
The ecological significance of leguminous crops grown in modern intensive crop rotation in Ukraine is considered. In particular, the sown areas of common leguminous crops in Ukraine and the level of their productivity have been analyzed. A comparison is made with the acreage of common field crops in Ukraine. The volume of accumulation of by-products in the form of their straw and stubble is calculated. A comparison is made for these indicators with the most widespread grain crops grown in Ukraine. The data on the content of the main nutrients in the by-products of leguminous crops – nitrogen, phosphorus, potassium are given. On the basis of these indicators, a calculation was made of the accumulation of the main nutrients in the soil, which can come with by-products of leguminous crops at their average yield. We also compared the obtained indicators with the input of nitrogen, phosphorus and potassium into the soil with by-products of the most common grain crops. Calculated symbiotic nitrogen fixation by leguminous crops. Based on this, a conclusion was made about the most effective leguminous crops, the cultivation of which in the modern intensive crop rotation of Ukraine will more contribute to the stabilization of the agroecological state of the soil. It is proved that an increase in the areas of leguminous crops in the intensive crop rotation of Ukraine will have a positive effect on the agroecological state of the soil. In particular, growing beans allows you to get the highest mass of by-products, which can be buried in the soil – 3.5 t/ha. Also, the by-products of beans provide the input into the soil of all mineral phosphorus – 12.6 kg/ha of all leguminous crops, as well as potassium – 16.5 kg/ha. By-products allow to accumulate more mineral nitrogen in the soil with by-products – 38.4 kg/ha. Also, soybeans are characterized by a high symbiotic nitrogen-fixing ability among all leguminous crops – 120 kg/ha.
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Stockdale, Elizabeth, Paul Hargreaves e Anne Bhogal. "Developing soil health indicators for improved soil management on farm". In Advances in measuring soil health, 289–328. Burleigh Dodds Science Publishing, 2021. http://dx.doi.org/10.19103/as.2020.0079.22.
Testo completoAbstract (sommario):
A range of chemical, physical and biological processes are important for sustained productivity and environmental quality in agricultural systems. Farmers and scientists share a concern with soil health, and this leads to questions for both measurement and management. An essential step is to define the context and the key functions required of a soil at the scale of interest (e.g. farm, drinking water catchment, region). Only then can appropriate indicator measurements be selected. Current soil health frameworks across the world commonly use organic matter (carbon), pH, extractable phosphorus, and various indicators of soil structure/water storage. A framework of interpretation shows whether the measured values are acceptable or whether one or more soil functions are constrained. A number of the soil health frameworks in practical use present the soil health indicators in a scorecard using traffic light coding to direct users towards guidance for improved soil management on-farm.
Atti di convegni sul tema "Soils Phosphorus content"
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Skyba, O. I., L. Ya Fedonyuk, O. M. Yarema e K. Lesnyak-Mochuk. "DEPENDENCE OF PHOSPHATE CONTENT IN WATER ON MOBILE AND TOTAL FORMS OF PHOSPHORUS IN SOIL IN AGRICULTURAL TERRITORY OF TERNOPIL REGION (UKRAINE)". In SAKHAROV READINGS 2021: ENVIRONMENTAL PROBLEMS OF THE XXI CENTURY. International Sakharov Environmental Institute of Belarusian State University, 2021. http://dx.doi.org/10.46646/sakh-2021-2-213-217.
Testo completoAbstract (sommario):
The indicators of phosphates in water, the content of mobile and total forms of phosphorus in bottom sediments and soils in the hydroecosystem of the agrarian territory, which is characterized by active agriculture and animal husbandry, have been determined and analyzed. It was found that the presence of the total form of phosphorus in soil, water and bottom sediments differs significantly in different months, and the mobile form, on the contrary, is the same. It indicates a significant mobility of mobile forms of phosphorus in the “soil-water-bottom” sediments system. It was found that in spring most of the total phosphorus is in the soil, and in summer and until the beginning of autumn, its share in bottom sediments increases. It was revealed that the content of phosphates in the studied hydroecosystem is determined by their migration in the “soil-water-bottom” sediments system and has a seasonal character.
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Zolotarev, Vladimir. "Efficiency of fertilizer application on seed stands of birdsfoot trefoil". In Multifunctional adaptive fodder production. ru: Federal Williams Research Center of Forage Production and Agroecology, 2021. http://dx.doi.org/10.33814/mak-2021-25-73-50-58.
Testo completoAbstract (sommario):
On sod-podzolic medium-loamy soils of the Central Non-Chernozem region of Russia with an average availability of mobile forms of phosphorus and an average close to low potassium content, high efficiency of using potash fertilizer together with phosphorus on birdsfoot trefoil seed crops was established. Effective doses of phosphorus-potassium fertilizers, providing an increase in seed yield in the first year by 42–47% and, according to the aftereffect, in the second year by 17–33%, are the application of P30–60K90–120.
Keywords: Birdsfoot trefoil (Lotus corniculatus L.), seed herbage, phosphoric and potash mineral fertilizers, yield, seeds, sowing qualities.
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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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Plekhanova, Liudmila. "SOILS OF SMALL ARCHAEOLOGICAL SETTLEMENTS IN THE STEPPE ZONE AS A RESULT OF BRONZE AGE ANTHROPOGENIC IMPACT". In GEOLINKS Conference Proceedings. Saima Consult Ltd, 2021. http://dx.doi.org/10.32008/geolinks2021/b1/v3/43.
Testo completoAbstract (sommario):
"The contemporary direction of natural pedogenesis/soil science is ancient anthropogenic impact and climate fluctuations changes. A large number of settlements in the river valleys are unique objects with a long history of development and modern soil cover formation. We studied the soil between the dwellings for a small settlement Zarya of the Bronze Age. The settlement was part of the economic zone of cattle breeding (horses and cows and sheep) of the large early Bronze Age fortified city Sarym-Sakla, one of the country's Proto-Iranian Cities of the Trans-Ural Plateau. The activity of ancient societies changed the terrestrial ecosystem functioning at macro and microscales. Increased heterogeneity of microrelief forms led to the diversity of soil cover. We found the unusual soil types on microelevations and microdepressions. The enrichment of the cultural layer with phosphorus compounds was revealed, and the hypothesis of the formation of a ""reverse"" ratio of chernozems-solonetzes of the soil cover of the low above-floodplain terrace as a consequence of several stages of ancient anthropogenic pressure and climatic aridization was confirmed in this area. We focused on the determination of organic carbon content, magnetic susceptibility, salt composition, cation exchange capacity, and the distribution of mobile phosphates along the soil profile as possible indicators of ancient anthropogenic influence. The degree of soil properties changes during the anthropogenic impact is commensurate with their transformation in the natural evolution of centuries and even several millennia. Past anthropogenic changes leave a mark in the history of the development of the soil cover predetermining the modern danger of the degradation phenomena. Moreover, we draw parallels in the history of ecosystems formation and outlined tasks for further research."
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Zhuk, Ekaterina. "Effect of nitrogen fertilizer Life Force Humic N on the yield and quality of the green mass of corn in the conditions of the Republic of Belarus". In Multifunctional adaptive fodder production. ru: Federal Williams Research Center of Forage Production and Agroecology, 2022. http://dx.doi.org/10.33814/mak-2022-28-76-134-138.
Testo completoAbstract (sommario):
Corn plays a leading role in providing the livestock industry with green and juicy feeds. To increase the yield and quality of green mass, the use of nitrogen fertilizers is of great importance [1]. In a field experiment on sod-podzolic soils in the conditions of the Minsk region, on the basis of LLC "Gastellovskoye" of the Minsk district, the influence of nitrogen fertilizer Life Force Humic N on the yield and quality of the green mass of the Dolphin corn hybrid was studied. Water-soluble nitrogen fertilizer Life Force Humic N on corn crops was used in phases: 4–6 leaves, sweeping of the panicle and the beginning of flowering of the crop. The content of the main elements of nutrition (nitrogen, phosphorus, potassium) in the green mass of corn under the influence of the fertilizer Life Force Humic N varied within the error of the experiment and at the level with the use of control. No significant changes in the protein content depending on the use of equivalent doses of mineral nitrogen (control) and Life Force Humic N fertilizer have been established. The maximum protein content (5.6–5.7%) was noted both in the variant with the use of top dressing with standard nitrogen fertilizer and with the Life Force Humic N. fertilizer. When cultivating corn for green mass, the use of three-fold non-root treatment of crops with liquid water-soluble nitrogen fertilizer Life Force Humic N increased the yield of the green mass of the crop by 31 c / ha. When cultivating corn for green mass, the use of non-root treatments with Life Force Humic N fertilizer at a dose of 1 l/ ha is recommended.
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Kuzmenko, N. N. "COMPARATIVE EFFICIENCY OF DIFFERENT DOSES OF FERTILIZERS WHEN CULTIVATING FIBER FLAX". In STATE AND DEVELOPMENT PROSPECTS OF AGRIBUSINESS. DSTU-PRINT, 2020. http://dx.doi.org/10.23947/interagro.2020.1.633-636.
Testo completoAbstract (sommario):
When cultivating fiber flax, it is recommended to calculate the doses of fertilizers for the main application by compensating for their removal by the crop. On sod-podzolic medium-loamy soil with mobile phosphorus content from high to very high, low and medium potassium content, phosphorus must be compensated by 100% due to fertilizers, and potassium-by 120 %. The optimal dose is N15P22K80. Fiber flax
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Teberdiev, Dalhat, Anna Rodionova e Sergey Zapivalov. "INFLUENCE OF TECHNOLOGICAL PROCESSES AND FERTILIZERS SYSTEMS FOR LONG-TERM PRODUCTIVITY HAYMAKING AND SOIL FERTILITY". In Multifunctional adaptive feed production. ru: Federal Williams Research Center of Forage Production and Agroecology, 2020. http://dx.doi.org/10.33814/mak-2020-22-70-34-39.
Testo completoAbstract (sommario):
When using long-term haymaking (73 years of use), the regularities of the influence of fertilizers and technological systems on the productivity and fertility of the soil are established. When using a technogenic system (without fertilizers), the productivity was 31.9 GJ/ha of exchange energy, the content of mobile phosphorus in the soil decreased by 37%, exchange potassium-by 19%, humus increased from 2.03 to 3.05%, with an annual humus content of 18 kg/ha. The highest productivity of haymaking over the past 27 years of use was observed in the technogenic-mineral system when using N180P45K90 —– 72.5 GJ/ha of exchange energy, 5.6 thousand feed. units, 922 kg/ha of raw protein. The content of mobile phosphorus in the soil increased by 232% compared to the initial one, humus from 2.03 to 2.94%, exchange potassium decreased by 18%, and the average annual accumulation of humus was 28 kg/ha.
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Shi, Longmin, e Yong Liu. "Soil phosphorus content prediction based on improved PSO-LSTM algorithm". In 2021 IEEE International Conference on Artificial Intelligence and Computer Applications (ICAICA). IEEE, 2021. http://dx.doi.org/10.1109/icaica52286.2021.9498012.
Testo completo
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Stojic, Natasa, Mira Pucarevic, Milica Živkovic, Vesna Teofilovic e Dunja Prokic. "UTICAJ OTPADA NA FIZIČKO-HEMIJSKE KARAKTERISTIKE ZEMLJIŠTA". In XXVI savetovanje o biotehnologiji sa međunarodnim učešćem. University of Kragujevac, Faculty of Agronomy, 2021. http://dx.doi.org/10.46793/sbt26.351s.
Testo completoAbstract (sommario):
Land exploitation directly affects the physico-chemical characteristics of the soil. Agricultural land can often be seen near the landfills. The question is how much waste affects the production potential of land. The research in this paper is focused on the influence of the municipal waste landfill on the physico-chemical characteristics of the soil. In soil samples were analyzed: pH in KCl, pH in H2O, CaCO3, humus, total nitrogen, P2O5, K2O and organic carbon. The obtained results indicate a negative impact of waste on the content of OC and the content of easily accessible phosphorus and potassium.
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BRIUKHANOV, Aleksandr, Sergey KONDRATYEV, Veronica TARBAEVA, Ekaterina VOROBYEVA e Natalia OBLOMKOVA. "CONTRIBUTION OF AGRICULTURAL SOURCES TO NUTRIENT LOAD GENERATED ON THE RUSSIAN PART OF THE BALTIC SEA CATCHMENT AREA". In RURAL DEVELOPMENT. Aleksandras Stulginskis University, 2018. http://dx.doi.org/10.15544/rd.2017.058.
Testo completoAbstract (sommario):
Agricultural production is one of the main sources of nitrogen and phosphorous inputs to the water bodies. Quantifying nutrient input from agriculture is needed both to develop effective environmental measures and to justify the technologies to be applied with due account for local natural and climatic conditions. Several related national studies have been conducted since 2015. Institute for Engineering and Environmental Problems in Agricultural Production (IEEP) methodology was used for this purpose. It determines the nitrogen and phosphorus content in the arable layer, including N and P amounts applied with mineral and organic fertilisers. Such factors as soil type and texture, the distance to the water bodies and the land use structure are used to estimate the nutrient input to the water bodies. In addition, the consistency of manure handling technologies with Best Available Techniques (BAT) principles is taken into account through introduction of relevant coefficients. Calculation results according to IEEP methodology were used in the follow-up general assessment of the nutrient load on the water bodies from different sources with the use of Institute of Limnology Load Model. Satisfactory correspondence between the assessment results and the values calculated using the monitoring data confirmed the adequacy of the above assessment procedure. Following its outcomes, the nutrient reduction potential of agricultural sources is approximately 10–20 %.
Rapporti di organizzazioni sul tema "Soils Phosphorus content"
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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.
2
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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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.
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Pille, Katrina, e James R. Russell. Effects of Season and Soil Available Phosphorus Content on the Phosphorus Concentration of the Forage in Cool-Season Grass Pastures of Southeastern Iowa. Ames (Iowa): Iowa State University, gennaio 2013. http://dx.doi.org/10.31274/ans_air-180814-685.
Testo completo
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Raghothama, Kashchandra G., Avner Silber e Avraham Levy. Biotechnology approaches to enhance phosphorus acquisition of tomato plants. United States Department of Agriculture, gennaio 2006. http://dx.doi.org/10.32747/2006.7586546.bard.
Testo completoAbstract (sommario):
Abstract: Phosphorus is one of the least available macronutrient in the soil. The high affinity phosphate transporters are known to be associated with phosphate acquisition under natural conditions. Due to unique interactions of phosphate with soil particles, up to 80% of the applied phosphates may be fixed forcing the farmers to apply 4 to 5 times the fertilizers necessary for crop production. Efficient uptake and utilization of this essential nutrient is essential for sustainability and profitability of agriculture. Many predictions point to utilization/exhaustion of high quality phosphate rocks within this century. This calls for efforts to improve the ability of plants to acquire and utilize limiting sources of phosphate in the rhizosphere. Two important molecular and biochemical components associated with phosphate efficiency are phosphate transporters and phosphatases. This research project is aimed at defining molecular determinants of phosphate acquisition and utilization in addition to generating phosphate uptake efficient plants. The main objectives of the project were; Creation and analysis of transgenic tomato plants over-expressing phosphatases and transporters Characterization of the recently identified members (LePT3 and LePT4) of the Pi transporter family Generate molecular tools to study genetic responses of plants to Pi deficiency During the project period we have successfully identified and characterized a novel phosphate transporter associated with mycorrhizal symbiosis. The expression of this transporter increases with mycorrhizal symbiosis. A thorough characterization of mutant tomato lacking the expression of this gene revealed the biological significance of LePT3 and another novel gene LePT4. In addition we have isolated and characterized several phosphate starvation induced genes from tomato using a combination of differential and subtractive mRNA hybridization techniques. One of the genes, LePS2 belongs to the family of phospho-protein phosphatase. The functionality of the recombinant protein was determined using synthetic phosphor-peptides. Over expression of this gene in tomato resulted in significant changes in growth, delay in flowering and senescence. It is anticipated that phospho-protein phosphatase may have regulatory role in phosphate deficiency responses of plants. In addition a novel phosphate starvation induced glycerol 3-phosphate permease gene family was also characterized. Two doctoral research students are continuing the characterization and functional analysis of these genes. Over expression of high affinity phosphate transporters in tobacco showed increased phosphate content under hydroponic conditions. There is growing evidence suggesting that high affinity phosphate transporters are crucial for phosphate acquisition even under phosphate sufficiency conditions. This project has helped train several postdoctoral fellows and graduate students. Further analysis of transgenic plants expressing phosphatases and transporters will not only reveal the biological function of the targeted genes but also result in phosphate uptake and utilization efficient plants.