Rozprawy doktorskie na temat „Chemical fertility”
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Goswami, Suranjana. "IDENTIFICATION OF PHOSPHOPROTEINS INVOLVED IN SPERM MATURATION AND FERTILITY". Kent State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=kent1532952768427828.
Pełny tekst źródłaWalworth, James. "Soil Sampling and Analysis". College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2006. http://hdl.handle.net/10150/144813.
Pełny tekst źródłaSoil testing is comprised of four steps: Collection of a representative soil sample, laboratory analyses of the soil sample, interpretation of analytical results, and management recommendations based on interpreted analytical results.
Walworth, J. L. "Soil Sampling and Analysis". College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2011. http://hdl.handle.net/10150/239610.
Pełny tekst źródłaRamahlo, Masetle Nelson. "Physico-chemical and biological characterization of soils from selected farmlands around three mining sites in Phalaborwa, Limpopo Province". Thesis, University of Limpopo (Turfloop Campus), 2013. http://hdl.handle.net/10386/1127.
Pełny tekst źródłaThe study was conducted to assess the impact of mining activities on selected soil physical, chemical and microbial properties on farmlands around three selected mining sites. Nine soil samples were collected from each of the following farms : Hans Merensky, Mogoboya and Leon Tom, Foskor Mine and JCI mining sites, respectively. Additional nine soil samples were collected from non-polluted Waterbok farm that serves as a control for the purpose of comparison. The samples were taken at 0–15, 15–30, 30–45 cm depths at three sampling points on each farm for physical, chemical and biological studies. However, soil samples collected for microbial (fungi, bacteria and actinomycetes) counts were surface (0–15 cm) soil samples. Soil chemical properties determined include pHw, electrical conductivity (ECe), exchangeable acidity (EA), organic carbon, available phosphorous, exchangeable cations as well as heavy metal (i.e. Mn, Zn, Cu, Pb, Cd, As and Sb) concentrations. The physical parameters determined include texture (sand, silt and clay) as well as bulk density. Soil pHw and ECe values decreased with depth; and ranged from 6.94 to 6.50 and from 12.24 to 10.76 mS cm-1, respectively. Exchangeable acidity showed a gradual increase with depth and ranged from 0.72 to 0.80 cmol(+)(kg), while percent organic carbon decreased with depth ranging from 1.41 to 2.19 %. Exchangeable cations, particularly K and Mg increased with depth while Ca decreased marginally with soil depth. Available phosphorous content decreased following increases in distance from the pollution source while heavy met.al contamination decreased with soil depth but increased further away from the pollution source. Significantly high loads of Pb, As and Sb were recorded at all depths on the three farms around the mining sites, which were largely responsible for the pollution but worse on the Leon Tom farm; with Pb constituting the greatest pollutant. The concentration of extractable heavy metals in the studied areas was in the order: As >Sb>Pb>Zn>Cu >Mn >Cd. Cadmium level appeared generally very low in all samples while elevated levels of Mn, Cu and Zn were detected at all depths in the polluted soils.Significant differences in microbial levels were detected at the various sampling points. The highest count of 3.82 and 6.20 CFU g-1 for fungi and actinomycete, respectively were both from the Leon Tom farm, while 6.46 CFU g-1 counts for bacteria was obtained from Mogoboya farm. Interestingly, fungal and actinomycetes activities were more sensitive to heavy metal contamination than bacteria that were significantly increased following soil pollution.
National Research Foundation (NRF)
Rue, Marie. "Hyperaccumulation du nickel sur des substrats élaborés pour l’agromine". Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0124/document.
Pełny tekst źródłaIn view of the depletion of primary resources and the increase in global waste production, the concept of agromining proposes phytoextracting the metals contained in abandoned materials. The solution proposed in this concept is inspired by Nature (NbS) and the principles of agronomy and is part of a circular economy. Thus, hyperaccumulator plants (HA) are able to collect metals from their root system and to store them at high concentrations in their aerial parts. The challenges of the thesis are to give value to waste or secondary materials by extracting the elements of interest that they contain and to identify the plants able to develop on these media. The objective is to formulate, from the chosen materials, a functional substrate, that is to say, capable of rendering a Ni supply service. From this point of view, the substrate must allow the installation and the development of the HAs in order to transfer the metals to the aerial parts. The work focuses on an acid phosphating sludge essentially composed of Fe, Zn, P and Mn and containing 0.5% Ni. Germination and growth tests were carried out with different substrates prepared from this sludge assembled with a soil sample mixture. The retained substrate consists of 10% sludge and 90% soil (w/w). On the latter, HA Alyssum murale produces a higher biomass compared to a control soil (ultramafic soil at the same pH and containing the same amount of bioavailable Ni), despite signs of toxicity to plants. One of the major locks is the high toxicity due to the presence of 6% Zn in the sludge. Two ways of improving the substrate are tested: i) the use of amendments and ii) the arrangement of materials in the profile. The most efficient amendment is a wood biochar; it improves the development of plants and thus the amount of phytoextracted Ni. In addition, by modifying the layout of the materials within the profile by a layered distribution, biomass production and phytoextraction are improved. This device makes it possible to remove Zn-related toxicity. It is essential to control the pH of the substrate during multi-contamination because the immobilization of the metal varies according to the element. The association of soil engineering and plant engineering has made it possible to formulate a functional substrate for the recovery of elements of interest such as Ni. This work demonstrates the possibility of upgrading by-products conventionally called "waste" in order to obtain a surplus value, also reducing their metallic charge and bringing about a new source of "plant-derived" metals obtained by agromining
Subedi, Santosh. "Determination of fertility rating (FR) in the 3-PG model for loblolly pine (Pinus taeda L.) plantations in the southeastern United States". Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/52588.
Pełny tekst źródłaPh. D.
Stewart, Ryan. "Physical and Chemical Parameters of Common Soils in the Central Plateau Region of Haiti". Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/32199.
Pełny tekst źródłaMaster of Science
LTRA-6 (A CAPS program for the Central Plateau of Haiti)
Stewart, Ryan D. "Physical and Chemical Parameters of Common Soils in the Central Plateau Region of Haiti". Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/32199.
Pełny tekst źródłaMaster of Science
LTRA-6 (A CAPS program for the Central Plateau of Haiti)
Bregagnoli, Marcelo. "Qualidade e produtividade de cultivares de batata para indústria sob diferentes adubações". Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/11/11136/tde-19052006-154403/.
Pełny tekst źródłaThis research was conducted to study the behavior of potato cultivars for industrial use under different fertilization levels. To measure the agronomic behavior, quality of tubers and nutrient exportation by tubers, as well as the productivity of the following common bean crop, two experiments were conducted at two different localities, in high- and low-fertility soils, respectively, at the experimental field of the horticulture section, Escola Superior de Agricultura Luiz de Queiroz USP, Piracicaba, SP, from July to November 2003 and at Fazenda Goiabeiras, Nova Resende, MG, from June to October 2004. Under high soil fertility, the tubers from the cultivars Atlantic, Asterix and Lady Rosseta were planted at 4 fertilization levels with 4 replications. The experiment was arranged in randomized blocks design, with 1, 2 and 4 t of 4-14-8 ha-1 and, according to the soil analysis results, with 40 kg N ha-1 and 50 kg of P2O5 ha-1. The same scheme was adopted in the second experiment, except for the fertilization based on soil analysis: 40 kg N ha-1, 420 kg ha-1 P2O5 (simple superphosphate) with 335 kg at planting and 85 kg in top dressing and 220 kg ha-1 of potassium chloride, being 45 at planting and 175 in top dressing. From the results we concluded that the cultivar Lady Rosetta, in both high- and low-fertility soils, showed lower growth than Atlantic and Asterix. The cultivar Atlantic has shown to grow and produce well with stable quality in soils of different fertility conditions. Lady Rosetta, on the other hand, has shown to be less adapted, showing sprouting problems. Excessive fertilization negatively influenced productivity and tuber quality in both high and low-fertility soil conditions under restricted irrigation. The balanced fertilization recommended following soil analysis results, with simplified formulations, in a high-fertility soil, resulted in satisfactory productivity and high levels of dry mass when compared to concentrated formulations, even though shoot development was not favored. In the low-fertility sandy soil, the fertilization with 2 t of 4- 14-8 has shown to be efficient for potato production and provided residual nutrients to the following common bean crop. The low-fertility soil with restricted irrigation resulted in higher dry mass of tubers in all cultivars, especially Lady Rosetta, if compared to highfertility soil. Fertilization as recommended following soil analysis results, especially to the low-fertility soil favored the level of dry mass, mainly in cultivar Asterix. The excess of nutrients such as K, negatively influenced the behavior of other elements (e.g. Mg), in soils of both high and low fertility.
Chaparro, Francisco Javier. "Biocompatible Electrospun Vehicles To Enhance the Effectiveness Of Anti-Fertility Strategies And Their Biomimetic Properties As Blood Vessel Scaffolds". The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1514986344784852.
Pełny tekst źródłaClesse, Margaux. "Étude multi-sites de la réponse de la fertilité chimique des écosystèmes forestiers dans un contexte de changements (dépôts atmosphériques et substitution d’essences)". Electronic Thesis or Diss., Université de Lorraine, 2023. http://www.theses.fr/2023LORR0009.
Pełny tekst źródłaForest ecosystems often grow on acidic, nutrient-poor soils. In many places, high acidic atmospheric deposition (sulfuric and nitric acids) has significantly accelerated the acidification of soils and surface waters during the second half of the 20th century, frequently leading to soil fertility degradation and forest decline. In addition, species selection and/or substitution by forest management can also have a significant effect on the biogeochemical functioning of soils and forest ecosystems. In this context, their sustainability is questioned and it is necessary to quantify the evolution of the chemical fertility of forest ecosystems in the face of these pressures and to better understand their biogeochemical functioning, in order to ensure sustainable forest management. The main objectives of this thesis are i) to quantify the evolution of chemical fertility of forest ecosystems using four diagnosis methods: soil resampling, monitoring of soil solutions, foliar concentrations and calculation of the "input-output" budget, ii) to understand the mechanisms underlying this evolution and iii) to compare the results obtained by the different methods, taking into account the uncertainty surrounding the budget. To do this, we quantified the evolution of fertility over a period of 20 to 30 years by these 4 methods, on monospecific plots of the Breuil-Chenue site and on 8 level III plots of the RENECOFOR network. The results showed that the species had an effect on soil acidification and on the pools of exchangeable nutritive cations in the soil. Hardwoods appear to acidify soils less intensely than coniferous. A restoration of pH is observed under oak and beech, whereas acidification seems to continue under coniferous, especially under Douglas fir and pine, and even more under Nordmann fir and spruce. Soil acidification and associated nutrient losses have also been demonstrated on some RENECOFOR sites. Nitrate and sulphate seem to be the main drivers of acidification. However, their origin depends on the site studied: they are sometimes derived from current atmospheric deposition, but internal sources to the ecosystem may also intervene via excess nitrification (especially under Douglas fir, pine, oak at Breuil and CPS 77) or desorption of S into the soil (especially on RENECOFOR sites). Leaching of S and N and associated cations tends to acidify soils. However, the response of sites to acidification can vary, depending on the predominance of either biological or geochemical cycling. Sites identified with predominant geochemical cycling (CHS 41, CPS 77, HET 30, and SP 38) have nutrient pools supported more by weathering and atmospheric deposition fluxes, whereas the sites dominated by biological cycling (EPC 08, EPC 87, PS 67a, SP 57) have nutrient pools supported primarily by recycling fluxes. Finally, the results showed that the comparison between the different fertility diagnosis methods is not easy. Differences were highlighted, with sometimes contradictory results. Taking into account the uncertainty around the budget does not alone explain the differences observed by the soil resampling approach. Uncertainty in the choice of model could perhaps partly explain the origin of the discrepancies. This work highlights the importance of continuing research on i) understanding the response of forest ecosystems to changes in atmospheric deposition and species substitution and ii) assessing the uncertainties surrounding the different approaches to fertility diagnosis
Galdeano, Larissa Ruas. "Fertilidade e mineralogia do solo sujeito à disposição de vinhaça de uma fazenda em Santa Cruz das Palmeiras /". Rio Claro, 2019. http://hdl.handle.net/11449/182301.
Pełny tekst źródłaResumo: Com a crescente produção de etanol no Brasil, houve o aumento da geração da vinhaça, que em certas condições pode ser utilizada para a fertirrigação de lavouras de cana-de-açúcar com o intuito de elevar a fertilidade do solo. A pesquisa consistiu na análise temporal e espacial de dados das características químicas e físicas dos solos de uma lavoura de cana-de-açúcar e da vinhaça aplicada, além da análise granulométrica, química e mineralógica de seis amostras de solo coletadas na área de estudo. A partir dos resultados obtidos, observou-se que elevados volumes de vinhaça foram calculados em 2014, sendo que os resultados indicaram baixas condições de fertilidade com altas concentrações de H+Al e de CTC total. A análise temporal de uma das glebas da fazenda demonstrou que, em dosagens previamente calculadas, a aplicação de vinhaça pode melhorar a fertilidade do solo e promover a redução da acidez e da toxicidade por alumínio. As análises granulométricas, químicas e mineralógicas caracterizaram o latossolo vermelho da área de estudo como um solo arenoso muito fino a médio com altas concentrações de silicatos e óxidos e hidróxidos de ferro e alumínio com minerais de gibbsita, hematita, quartzo e argilominerais do grupo da caulinita. O estudo avaliou a possibilidade de lixiviação dos cátions de base e de concentração de íons H+ e Al3+ pela hidrólise total e parcial da caulinita e da gibbsita e da decomposição da Matéria Orgânica no período chuvoso, sendo que a fertirrigação repõe ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: As the ethanol production has been developing in Brazil, it resulted on the increase of vinasse generation, which under certain conditions can be used for fertirrigation of sugarcane plantations in order to increase soil fertility. The research consisted of temporal and spatial data analysis of chemical and physical characteristics of soils of the soils of a sugar cane yield and the applied vinasse, in addition to the granulometric, chemical and mineralogical analysis of six soil samples collected in the research area. From the results obtained, it was observed that high volumes of vinasse were calculated in 2014, as the results had also indicated low fertility conditions with high concentrations of H+Al and total CEC. The temporal analysis of the plot 15 demonstrated that, in controlled doses, the application of vinasse can improve soil fertility and promote reduction of acidity and toxicity by aluminum. The granulometric, chemical and mineralogical analyzes characterize the red latosol of the research area as a very fine to medium sandy soil with high concentrations of silicates and oxides and hydroxides of iron and aluminum with minerals of gibbsite, hematite, quartz and clay minerals of the kaolinite group. The research evaluated the possibility of leaching of base cations and concentration of H+ and Al3+ ions by total and partial hydrolysis of kaolinite and decomposition of Organic Matter (OM) in rainy season, with soil moisture restoring and reposition of macronutrients... (Complete abstract click electronic access below)
Mestre
Berthold, Dirk. "Soil chemical and biological changes through the N2 fixation of black locust (Robinia pseudoacacia L.) - A contribution to the research of tree neophytes". Doctoral thesis, Göttingen, 2005. http://webdoc.sub.gwdg.de/diss/2005/berthold.
Pełny tekst źródłaLins, Caio Buainain. "Diagnóstico da fertilidade do solo e estimativas de recomendação de calagem e adubação NPK para o Mato Grosso do Sul". Universidade Federal de Viçosa, 2012. http://locus.ufv.br/handle/123456789/5494.
Pełny tekst źródłaThe diagnosis of soil fertility, when performed based on soil analysis results of a certain State of the Federation, can serve as an instrument to assist in the planning and definition of public policies related to the productive sector of the State. The work had as objectives: diagnosing soil fertility of Mato Grosso do Sul (MS); establish relationships between some attributes of soils studied; compare the recommendations of liming and fertilizing obtained by different technical bulletins of recommendation used in MS, to its main agricultural crops, with the data acquisition (NPK) or production (calcareous) in the State of MATO GROSSO DO SUL in 2010. In this work it were used chemicals and physicals results database of soil State of MS. This database, was obtained with a soil analysis laboratory that operates in the State of MATO GROSSO DO SUL, is referring to the results of analyses of 8,125 samples collected in layers of 0 to 20 cm in the year 2010. All samples were analyzed chemically, by establishing: pH (CaCl2); P (Mehlich-1); K (Mehlich-1); Ca2 +; Mg2 +; Al3 +; (H + Al) and organic matter (M.O.). Were calculated the sum of the bases (SB), base saturation (V) and CTC at pH 7 (T). Textural and P-resin (P-Res) analyses were performed at 1,813 and 907 samples, respectively. Soil fertility diagnosis of MS was performed by descriptive statistics: frequency, median, standard deviation, amplitude and the mean of the attributes of the soil in the State. Were evaluated the relationship between the meaning of P (Mehlich-1) with P-Res and clay; the meaning of M.O. with T and V with pH (CaCl2). Were compared the quantities of calcareous produced and the total of NPK consumed in the State with the estimated recommendation of lime and NPK for the main crops of the State (pasture, soy, corn, sugar cane and eucalyptus). Lime recommendations , were determined by the method of saturation by bases, and the estimated fertilization were carried out on the basis of: percentages frequency of soil fertility classes, the area (ha) of a crop and by technical bulletins of recommendation used in MS.1) as regards the diagnosis of fertility: 21.74% of samples have pH in CaCl2 less than or equal to 4.8; 82.18% of samples have aluminum meaning less than or equal to 0.2 cmolc dm-3; 7.35% of the samples have bases saturation less than or equal to 35%; 46.16% phosphorus samples were below the critical level for annual crops; 12.53% potassium samples are below critical levels for annual crops; 10.72% of calcium + magnesium samples were below the critical level for annual crops. 2) the production of calcareous in MS was insufficient to State consumption in 2010. 3) N is the nutrient used in smaller quantities in relation to the recommendations, followed by P. 4) the quantities of K2O used in MS in 2010 were close to those recommended. 5) The relationships obtained in the form of equations, between soil attributes are useful to support pedotransfer functions.
O diagnóstico da fertilidade dos solos, quando realizado baseado em resultados de análises de solos de um determinado Estado da Federação, poderá servir de instrumento para auxiliar no planejamento e definição das políticas públicas ligadas ao setor produtivo daquele Estado. O trabalho teve como objetivos: diagnosticar a fertilidade dos solos do Mato Grosso do Sul (MS); estabelecer relações entre alguns atributos dos solos estudados; comparar as recomendações de calagem e adubação obtidas por meio de diferentes manuais de recomendações de corretivos e fertilizantes utilizados na região, para suas principais culturas agrícolas, com os dados de aquisição (NPK) ou produção (calcários) no Estado do MS em 2010. Foi realizado o levantamento das características químicas e da granulometria dos solos, utilizando-se banco de dados de resultados analíticos referentes aos solos do Estado do MS. O banco de dados, pertencente a um laboratório de análise de solo que atua no Estado do MS, é referente aos resultados de análises de 8.125 amostras coletadas nas camadas de 0 a 20 cm, no ano de 2010. Todas as amostras foram analisadas quimicamente, determinando-se: pH (CaCl2); P (Mehlich-1); K (Mehlich-1); Ca2+; Mg2+; Al3+; (H+Al) e matéria orgânica (M.O.). Foram calculadas a soma de bases (SB), saturação por bases (V) e CTC a pH 7 (T). Foram realizadas análises texturais e de P-Resina (P-Res) em 1.813 e 907 amostras, respectivamente. O diagnóstico da fertilidade dos solos do MS foi realizado por meio de estatísticas descritivas: frequência, mediana, desvio padrão, amplitude e a média dos atributos do solo no Estado. Foram avaliadas as relações entre o teor de P (Mehlich-1) com teor de P-res e argila; teor de M.O. com T e V com pH (CaCl2). Foram comparadas as quantidades de calcário produzidas e o total de fertilizantes NPK consumidos no Estado com as necessidades de calagem e de fertilização com NPK para as principais culturas do Estado (pastagem, soja, milho, cana-de-açúcar e eucalipto). As recomendações de calagem, determinadas pelo método de saturação por bases, e adubação foram realizadas com base nas: porcentagens de frequência das classes de fertilidade do solo, da área (ha) de ocupação das culturas e pelos principais boletins técnicos de recomendação utilizados no MS. 1) Quanto ao diagnóstico da fertilidade: 21,74 % das amostras têm pH em CaCl2 menor ou igual a 4,8; 82,18 % das amostras apresentam teor de alumínio menor ou igual a 0,2 cmolc dm-3; 7,35 % das amostras têm saturação por bases menor ou igual a 35 %; 46,16 % das amostras de fósforo apresentaram-se abaixo do nível crítico para culturas anuais; 12,53 % das amostras de potássio estão abaixo dos níveis críticos para culturas anuais;10,72 % das amostras de cálcio + magnésio apresentaram-se abaixo do nível crítico para culturas anuais. 2) A produção de calcário no MS foi insuficiente ao consumo do Estado em 2010. 3) O N é o nutriente utilizado em menor quantidade em relação as recomendações, seguido do P. 4) As quantidades de K2O utilizadas no MS em 2010 foram próximas às recomendadas. 5) Os relacionamentos obtidos, na forma de equações, entre atributos do solo são úteis para embasar funções de pedotransferência.
Rothpfeffer, Caroline. "From wood to waste and waste to wood : aspects on recycling waste products from the pulp mill to the forest soil /". Uppsala : Dept. of Forest Soils, Swedish University of Agricultural Sciences, 2007. http://epsilon.slu.se/200783.pdf.
Pełny tekst źródłaSilva, Maria Ligia de Souza. "Avaliação do comportamento de elementos traço essenciais e não essenciais em solo contaminado sob cultivo de plantas". Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/11/11140/tde-05012007-125647/.
Pełny tekst źródłaThe contamination of the soil is growing in the world. There are great expanses of soil polluted with trace elements, organic compounds, organometals and radioactive elements that appear in concentrations that can endanger the environment. The behavior of trace elements in soils and its phytoavailability with subsequent transport to the alimentary chain has been quite intensive object of studies worldwide. With the objective of evaluating the behavior of essentials and non essential trace elements in a polluted soil, it was evaluated the absorption of trace elements by plants, its phytoavailability by extractors and in which fraction of the soil the elements are present in larger amount. The present work consisted of two experiments, both done entirely in a greenhouse of the Department of Soil Science of ESALQ/USP, with experimental design entirely randomized, in which samples of soil accidentally contaminated with trace elements and species of plants of economical interest were used. The experiments were conducted from November, 2004 to April, 2005, using seven levels of contamination for each trace elements and two cultures, rice and soybean. Fertilization with NPK was done in order to assist the basic needs of each culture. The plants were grown until maturation. The variables evaluated were: development and vegetable production; absorbed and accumulated amount of Cd, Cu, Fe, Mn, Pb and Zn; In the soil were determined total concentrations (HNO3/ HCl 1:3) and concentrations available of the trace elements by the use of the solutions Mehlich-1, HCl 0,1 mol L-1, DTPA and Organic Acids and the availability of those elements through the correlation of the available concentrations in the soil with the concentrations in diagnostic leaf, leafs in end of the cycle and seeds of rice and soybean; and the concentrations of trace elements in fractions of soil. The soybean and the rice were sensitive to the levels of trace elements available in the soil, exhibiting phytotoxicity symptoms, mainly for Zn, manifested as chlorosis and inhibition of growth. The rice was more sensitive than the soybean to the presence those elements. For soybean, the four extractors were efficient for Cd, Cu, Pb and Zn, both for the correlation with concentrations in the leaf diagnosis and in the leaf in the end of the cycle, while for rice, the most efficient were Mehlich-1, HCl 0,1 mol L-1 and DTPA for the Cd, Cu, Fe and Zn. For Mn, only DTPA was efficient. For Fe, the extractors were not efficient. The extractor Organic Acids was more efficient in the evaluation of the phytoavailability of Cd, Cu, Pb and Zn for soybean. The largest concentrations of Cd, Cu, Mn and Zn in the soil are found in the fractions with stable chemical bounds (attached to oxides and residue) being the exchangeable fractions + soluble and organic of smaller representativeness in relation to the total found. The Pb, in spite of prevailing in the fractions liked to oxides and residue, offers great potential of environmental contamination since it is also present in the exchangeable + soluble and organic fractions in considerable concentrations. The same happens for Zn, for which the total concentration was higher.
Nogueirol, Roberta Corrêa. "Práticas de manejo e avaliação de extratores em solos da região tropical úmida". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/11/11140/tde-26032012-110343/.
Pełny tekst źródłaAn increase in the amount of Brazilian agricultural areas managed under no-till farming systems has been observed in recent years. In the same period has seen increasing demand for information on the variability in the soil fertility indices on which liming and fertilization recommendations are based. This variation is of concern to technicians and researchers working in regional networks of soil analysis laboratories, and to the agencies responsible for establishing recommendations for fertilizing soils. The accumulation of organic matter (OM) in soils may affect the efficiency of chemical extractants by causing physical and chemical alterations to soils, including ion-exchange reactions, reactions with soil minerals, liberation of organic anions, complexation of metallic cations, and oxi-redox reactions. This thesis aimed: (i) to determine the bioavailable concentrations of Ca, Mg, and K and the Ca:Mg:K relationship in soils, as well as the relationship between extractants and element concentrations in soybean plants grown in a no-till system amended with lime and gypsum; (ii) to evaluate the efficiency of extractants for Cu, Fe, Mn, and Zn in soils amended with sewage sludge over 13 years and cultivation with maize; (iii) to compare methods of digesting soil samples to quantify Cu, Fe, Mn, and Zn in soils amended with sewage sludge over 13 years and in soils amended with sewage sludge and composted sludge on a single application; and (iv) to assess the quality and degree of humification of OM in soils amended with OM under different management practices. Among the hypotheses tested were: (i) that higher OM concentrations in no-till system soils and amendment with lime and gypsum would lead to an overestimate in the nutrient concentrations extracted by resin; (ii) that the large amounts of organic compounds contributed by amendment with sewage sludge over a long time period would diminish the extraction strength of complexing solutions; (iii) that higher concentrations of soil OM would hamper digestion of the soil samples, making a mixture of HNO3 and HCl the most efficient; and (iv) that no-till areas would be distinguishable from areas amended with sewage sludge by organic compounds, with the degree of humification of OM higher in no-till areas. There was a significant correlation between extractants for Ca, Mg, and K, but no correlation between elemental concentrations in soils and concentrations in soybean plants; amendment with lime and gypsum had no effect on the concentrations of these elements in soybean. In the experiment involving soil amended for 13 years with sewage sludge there was only a significant correlation between Mn and Zn concentrations in soils and those in plants. Acidic solutions extracted larger quantities of micronutrients. In general, concentrations extracted by aqua regia were close to total soil concentrations, and an effect of amendment with sludge was only observed for Cu and Zn in the long-term experiment. The physical fractionation of OM was the most efficient method for correlating with the management systems. The predominant organic compounds as determined by nuclear magnetic resonance were similar across the study areas.
Junior, João de Deus Gomes dos Santos. "Fertilidade do solo no acúmulo de forragem e nutrição do capim-tanzânia sob pastejo na região dos cerrados". Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/11/11140/tde-08062005-155015/.
Pełny tekst źródłaThe number of systems of intensive pasture use in Brazil has been increase in recent years in an attempt to improve the animal husbandry as a feasible economic activity and capable of competing in the international market. Among the factors that increase meet yield, the management of soil fertility conditions stand out by its effects in promoting forage yield, that must be accomplished with an efficient utilization and conversion into animal product. An experiment was carried out at Embrapa Gado de Corte located in Campo Grande-MS, with the objective of evaluating the effect of four soil fertility conditions in the forage yield, macronutrients concentrations and accumulations in Tanzania-grass (Panicum maximum cv. Tanzânia) along the summer and fall growing seasons. The experiment was a split-plot in randomized complete block design, with three replications. The treatments consisted of the combinations of two rates of limestone, phosphorus, and potassium (CPK1 and CPK2) and two rates of nitrogen (N1 and N2) as follows: a) CPK1: application of 30 kg ha-1 year-1 of phosphorus and 50 kg ha-1 year-1 of potassium associated to liming to increase the base saturation percentage to 50%; b) CPK2: application of 60 kg ha-1 year-1 of phosphorus and 100 kg ha-1 year-1 of potassium associated to liming to increase the base saturation percentage to 70%; c) N1: 150 kg ha-1 year-1 of nitrogen; d) N2: 300 kg ha-1 year-1 of nitrogen. Samplings were carried out at regrowth periods of 0, 12, 19, 26, 34, and 40 days during summer growing season, and at 0, 10, 18, 25, and 31 days during fall growing season. For each regrowth period plant height and the leaf area index (LAI) were described as attributes that characterize the pasture in its structural point of view. At the end of summer growing season (at 40 days) leaf blade yields of 4616 and 3292 kg ha-1 were obtained for N1 and N2 rates, respectively. The yield responses to nitrogen were higher for leaf blades than for stems+sheaths, while the responses to limestone, phosphorus and potassium were higher for stems+sheaths. This results indicated the need of more studies about the effect of nutrients in the morphological plasticity of Tanzânia-grass. Concerning the macronutrients accumulations in Tanzânia-grass it was observed that the effect of the amount of forage dry matter was more significant than the dilution effect of nitrogen, phosphorus, potassium and sulfur. Concerning both growing seasons, the macronutrients accumulations were in decreasing order: K>N>Ca>Mg>P>S. In the summer growing season, the aboveground nitrogen accumulation rate was almost exclusively due to the accumulation of the nutrient in the leaf blades, with values of 1.3 and 2.6 kg ha-1 day-1 observed for leaf blade at nitrogen rates N1 and N2, respectively. Responses to nitrogen rates were different regarding the accumulation of aboveground nitrogen after 19 days, which was associated to height of 87 cm and 89 cm, and LAI of 2.2 and 3.2 for rates of nitrogen N1 and N2, respectively. The rates of limestone, phosphorus, and potassium significantly changed the exchangeable of calcium and magnesium concentrations in the soil, particularly in the top layers. On the other hand, rates of nitrogen were more effective in promoting the accumulation of calcium and magnesium in the plant and the variation in concentrations of these nutrients along the growing season, which were related to the expressive increase in forage dry matter. Soil fertilities conditions CPK1N1 and CPK1N2 support the leaf blades yields observed in the summer growing season. Likewise, these soil fertilizations supplied the nutritional needs during the fall growing season when it was observed that the forage yield was limited by climatic conditions.
Zorel, Daiane. "Atributos químicos e microbiológicos de solo cultivado com cana-de-açúcar sob manejo convencional e orgânico". Universidade Federal de São Carlos, 2011. https://repositorio.ufscar.br/handle/ufscar/115.
Pełny tekst źródłaThe identification of soil quality indicators that demonstrate the alterations occurred in areas under organic management is important to determine the sustainability of this kind of cultivation. The soil microbial biomass and activity have been considered as important indicators of soil quality, especially when different management systems are employed in agroecosystems. In this context, the aim of this work was to evaluate management systems (organic and conventional) of the sugar cane over the soil quality, analyzing the chemical attributes as organic matter, pH, potential acidity, aluminium, magnesium, calcium, potassium, cation-exchange capacity, (CEC), sum of bases (SB), and percent base saturation (%BS), as well as the microbiological attributes as number of fungi and bacteria, microbial biomass carbon (MBC), basal respiration (BR) and metabolic quotient (MQ). The soil analyses were taken in the period comprised between May/2009 and September/2010. Among the chemical parameters that most showed the alterations in soil caused by the management are pH, magnesium concentration, potential acidity, SB and %BS. Higher values obtained with these two last parameters in the organic systems with addition of compost and limestone (SOCA) or compost and corrective, especially, indicate soil fertility. There was no significant difference among the treatments concerning MBC probably because it is an area where only recently the experiments were established. An influence of the sampling period was observed, with high values in the higher rainfall period. Higher values of BR were detected in the organic systems, especially in May and August/2009, which was coincident with the higher rainfall period and temperature. Although no significant difference was verified, the higher values of MQ were verified in the conventional system. Concerning the number of fungi and bacteria, the microbial community seemed to respond better to the climate/rhizosphere than the treatments involving the different management systems. Among the parameters studied, the BR was the most effective parameter to detect changes that occur in the soil due to the management system, showing that the organic system altered the soil quality, which reflected in the microbial activity.
A identificação de indicadores de qualidade de solo que demonstrem as alterações ocorridas em áreas agrícolas é importante para determinar a sustentabilidade do sistema de cultivo. A biomassa e a atividade microbiana do solo têm sido apontadas como importantes indicadores de qualidade do solo, especialmente quando se avalia o efeito de diferentes sistemas de manejo em agroecossistemas. Neste contexto, o objetivo deste trabalho foi avaliar o efeito de sistemas de manejo (orgânico e convencional) da cana-de-açúcar sobre a qualidade do solo, analisando-se os atributos químicos como matéria orgânica, pH, acidez potencial, alumínio, magnésio, cálcio, potássio, capacidade de troca catiônica (CTC), soma de bases (SB), porcentagem por saturação de bases, (V %); e microbiológicos como número de bactérias e fungos, carbono da biomassa microbiana (CBM), respiração basal (RB) e quociente metabólico (qCO2). As análises de solo foram realizadas no período compreendido entre Maio/2009 a Setembro/2010. Entre os parâmetros químicos que mais mostraram as alterações no solo provocadas pelo manejo estão o pH, teor de magnésio, acidez potencial, SB e V%. Valores mais elevados obtidos com estes dois últimos parâmetros nos sistemas orgânicos com adição de composto e calcário (SOCA) ou composto e corretivo (SOCO), especialmente, indicam fertilidade do solo. Não houve diferença significativa entre os tratamentos quanto ao CBM provavelmente por ser área recém implantada. Houve influência da época de amostragem, observando-se valores mais altos na época de maior pluviosidade. Valores superiores de RB foram detectados nos sistemas orgânicos, especialmente em Maio e Agosto/2009, coincidente com períodos de maior pluviosidade e temperatura. Embora não tenha sido observada diferença significativa, os maiores valores de qCO2 foram verificados no sistema convencional. Em termos de contagem de fungos e bactérias, a biota microbiana do solo pareceu responder mais ao clima/rizosfera que aos tratamentos envolvendo os sistemas orgânico e convencional. Dentre os parâmetros estudados e no período de tempo analisado, a respiração basal foi o parâmetro mais efetivo para detectar mudanças que ocorreram no solo devido ao sistema de manejo, mostrando que o sistema orgânico alterou a qualidade do solo, refletindo na atividade microbiana.
Kassoma, Josina Nimi. "Adubação verde e mineral na produção de salsa e nas propriedades físicas e químicas do solo". Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/11/11136/tde-14122009-151919/.
Pełny tekst źródłaTwo experiments were conducted with the objective to evaluate green manure and mineral fertilization efficience on parsley yield and physical and chemistry of a Nitossol Vermelho eutrófico típico soil in Piracicaba, SP region. The experimental design was a randomized complete blocks with five replications. The treatments were three legume species (Mucuna-anã, Crotalária juncea and Crotalária spectabilis) and control, two parsleys variety (Graúda Portuguesa and Lisa Preferida) and mineral fertilization levels (0 and 1 Mg ha-1 of 20-00-20). In the first experiment, carried out from 4th December 2008 to 23th of May 2009, the green manures were cut, chopped and left on the soil surface, while in the second experiment, that was carried out from 22th January to 3rd of July 2009, the green manures were cut and left on the soil surface for thirty days before incorporation. The physical characteristics evaluated were; the density of the soil, total porosity, macroporosity and microporosity. The chemical characteristics evaluated were; material organic, pH, exchangeable bases (SB), H+Al, capacity of cationic exchange (CTC), P, K, Ca, Mg, B, Cu, Fe, Mn, e Zn. In relation to the Parsley were evaluated the following; total fresh mass production, fresh stalk mass, fresh leaf mass, total dry mass of the stalk, total dry mass of the leaf, leafy area and the number of leaves. Either on the first and the second experiment the C. juncea was the specie that produced most of the fresh mass, dry mass and content dry mass in respect to the others. The chemical and physical characteristics of the soil were not altered with the exception of the P, Ca and SB, which were superior for the C. spectabilis in respect of Mucuna-ana. The yield of the parsley Lisa Preferida has increased with green manure, with Mucuna-ana and C. spectabilis, on the first experiment. In general, the yield of the parsley Lisa Preferida was superior with the coverage of the mineral manure in respect to the absence of this practice, both for its cultivation, or for the cultivation of the Grauda Portuguesa in the presence and absence of the green manure, on the second experiment.
Grandisson, Mariane. "Gestion des systèmes d'agriculture itinérante sur brûlis dans l'ouest Guyane : contribution à l'étude de la reproductibilité et de la fertilité". Antilles-Guyane, 1997. http://www.theses.fr/1997AGUY0024.
Pełny tekst źródłaShifting cultivation on brulis (ai) is a convenient method of cultivation without inputs. After two or three crop cycles, the degradation of soil fertility forces farmers to move their crops and the land is left fallow. Fallowing can be used to reconstitute a biomass, which will release during the next production period, after burning, the mineral elements necessary for the growth and development of crops. The purpose of this study was to provide support for the decision, with a view to eventually establishing these traditional systems. It required an analysis of the management of Qi systems, an important component of reproducibility of fertility, and the condition of fixation. At first, the spatial management of these systems and their capacity to cope with the agro-ecological and socio-economic constraints of the environment, to reproduce, were studied. This study was carried out at the scale of the agrarian system and more precisely at the level of the production systems which correspond to the level of the choices and decisions of the farmers. In a second step, the evolution of the components of fertility, likely to influence the yield of cassava, was analyzed - the cassava constituting the main crop of West Guiana. Three levels were considered: the cropping system that allows to understand the modes of behavior and association of crops, but especially the cultivated plot and the experimental plot, place of measurement and monitoring. In the first stage of this work, a balancing capacity of the giblets is established from the Piaget model. This typology makes it possible to identify 5 functional types of giblets in the region and 2 modes of evolution. In the second stage, during a first cycle of giblets, after secondary forest, the evolution of stocks of carbon, nitrogen and exchangeable bases shows that there is no degradation in relation to the material organic soil. On the other hand, there is a decrease in exchangeable bases following the cultivation and in particular potassium. Comparing this decrease with the needs of the crop, it was possible to identify potassium as a factor limiting production
Diedrick, Keith Anthony. "Field Investigations of Nitrogen Fertility on Corn and Soybeans and Foliar Manganese-Glyphosate Interactions on Glyphosate-Tolerant Soybeans in Ohio". The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1281988981.
Pełny tekst źródłaYan, Shr-Chin, i 顏士欽. "Feasibility and fertility assessment of using acid washing and chemical extraction to remediate heavy metals contaminated soils". Thesis, 2005. http://ndltd.ncl.edu.tw/handle/97293300524737664530.
Pełny tekst źródła國立屏東科技大學
環境工程與科學系
93
Heavy metal contaminated soil events are constantly emerging in Taiwan. And, there is about 250 hectares farmland had found to be exceeded the soil pollution control standard. The priority task to develop a soil remediation technology was urgent. In this study, we formulated several soil samples with cadmium, copper and lead as materials, and collected a contaminated site soil to carry on the extraction of HCl, EDTA, and citric acid to evaluate the removal efficiency of heavy metals in different extractant concentration, times, and frequency. We also observed the changes of heavy metal bonding type and soil fertility before and after extraction. As a result, we expected to assess the suitability and remediation effectiveness of contaminated soil with acid washing and chemical extraction. We found the maxima extraction reached before 30 minutes and the most optimal concentration for extractants were 0.2 N HCl, 0.05 M EDTA and 2 M citric acid, respectively. The double extraction had better efficiency than single extraction. Except the copper contaminated soil sample from Changhua, the heavy metal content of all tested soils proceeded double extraction would conform to the soil pollution control standard. In addition, water washing after acid washing and chemical extraction would remove the remaining extractants and increase the heavy metals extraction efficiency. The efficiency of extractants were relative to soil physical properties, heavy metal content and soil-metal bonding types of the extracting effect of cadmium, lead and copper in tested soils, in which the soil pH value and heavy metal types were the most influential than others. The changes of heavy metal bonding type before and after extraction were affected by soil physical properties and initial contaminated forms. Cadmium and copper in tested soils before extraction existed major in lower-energy bonding forms except the Changhua soil, in which copper and lead existed in higher-energy bonding forms. Acid washing with HCl was found to be effective for removing heavy metals from the tested soils, but also increased the mobility of heavy metals in tested soil at the same time. The results of EDTA extraction would conduce to increase heavy metal content of lower-energy bonding forms in some tested soils. We found that acid washing lowered the soil pH, seed germination percentage and promoted the loss of basic ion and available nutrient. But the extraction with EDTA and water washing would facilitate to neutral the soil pH, which contributed the soil fertility improvement.
Pecku, Shantel. "The effect of water treatment residues on soil microbial and related chemical properties". 2003. http://hdl.handle.net/10413/3596.
Pełny tekst źródłaThesis (M.Sc.)-University of Natal, Pietermaritzburg, 2003.
Buyeye, Sicelo Malizo. "Some soil chemical and fertility aspects of the land disposal of a water treatment residue on selected soils of KwaZulu-Natal, South Africa". 2005. http://hdl.handle.net/10413/3377.
Pełny tekst źródłaThesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.
Musumuvhi, Thabelo. "Biochar and poultry manure effects on selected soil physical and chemical properties and maize (Zea Mays) in a dry environment". Diss., 2018. http://hdl.handle.net/11602/1087.
Pełny tekst źródłaDepartment of Soil Science
Poultry manure (PM) is an inexpensive source of fertilizer but it decomposes quickly and releases carbon and greenhouse gases. Biochar (BC) could be an alternative source of carbon to improve soil quality and reduce greenhouse gas emission. This study investigated the effect of co-application of BC and PM on selected soil physical and chemical properties and performance of maize. A field experiment was conducted at the University of Venda experimental farm during 2015/2016 and 2016/2017 seasons. The experiment was a 4 x 3 factorial arrangement consisting of four rates of BC (0, 5, 10 and 20 t ha-1) and three rates of PM (0, 2, and 4 t ha-1) in a RCBD arrangement replicated three times. Maize was planted in both seasons. After harvest, soil bulk density was determined at four soil depths (0-5, 5-10, 10-15, and 15-20 cm), while aggregate stability and selected soil chemical properties were determined at two soil depths (0-15 cm and 15-30 cm). Data were subjected to ANOVA using Genstat 17th edition. The least significant difference was used to compare the treatment means at P < 0.05. Soil aggregate stability, organic carbon, Ca2+, Mg2+, K+, maize dry matter and maize grain yield increased with increasing rates of BC and PM application at 0 - 15 cm depth in both seasons. The combination of BC at 20 t ha-1 and PM at 4 t ha-1 significantly (P < 0.05) decreased soil bulk density at 5 - 10 cm depth but increased soil available P and total N at the two depths in both seasons. The results of this study suggested that BC and PM improved soil ability to retain and supply nutrients through improved soil aggregate stability and reduced bulk density thereby improving maize dry matter and grain yield. Combining BC with PM proved to enhance the ability of soil to function by improving selected soil physical and chemical properties thereby improving maize dry matter and grain yield.
NRF
Unger, Malte Arne. "Relationships between soil chemical properties and forest structure, productivity and floristic diversity along an altitudinal transect of moist tropical forest in Amazonia, Ecuador". Doctoral thesis, 2010. http://hdl.handle.net/11858/00-1735-0000-0006-ADA3-B.
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