Academic literature on the topic 'CHEMICAL COMPOSITION OF SOIL'

Although the soil solution lies at the centre of many of the processes which occur in soils, little information is available on the chemical composition of the soil solutions of field soils, or on the temporal and spatial variability of such solutions. The suitability of an immiscible fluid centrifugation method for obtaining samples of the soil solution was evaluated. The method was found to be substantially free from interferences and well suited to routine use. It was adapted for use with soils of low bulk density. Yields of soil solution from soils at or near field capacity ranged from 20 to 50% of the total water present. However little or no soil solution could be extracted from dry soils. Displaced solutions were analysed for about 20 solutes principally by inductively coupled plasma spectroscopy. Typical solute concentrations in soil solutons from six neutral and calcareous soil series in the Oxford area were in the range 10^-2.4 to 10^-3.4 M for Na, K, Ca, S, Cl, N0₃, alkalinity and dissolved organic carbon (DOC); 10^-3.4 to 10^-4.4 M for Mg, Si and P and <10^-5.33 M for B, Li r Y, Ba, Mn, Cu, Fe, V, Zn, Al, Pb f Ni, Cd, Co, Sr and Mo. Short-range (5-10 m) variability was significantly less, and between-soil series variability significantly more, than the variability found between grass fields on the same soil series for most solutes. The main exception to this was N0₃ which exhibited a large between-field variability. In general, soil solutions from arable soils were more dilute than those from nearby pasture soils. Solutions from poorly drained sites on a heavy clay soil were more concentrated than those from freely draining sites on the same soil series. A year-long sampling programme showed that with the exception of P and alkalinity the concentrations of solutes in the soil solution changed significantly with time. The temporal range in the concentrations of solutes was found to increase in the order Si-Pandlt;alkalinity-Feandlt;Naandlt;Ca-Sr-Mg-Cuandlt;S-DOCandlt;K-Znandlt;Cl-pHandlt;Mn.

Daily aerosol samples were collected at the &Ccedil<br>andarli which is located on Aegean coast of Turkey. A rural site was selected to monitor atmospheric pollution by long range transport. Sampling was performed in both summer and winter seasons, and in total 151 samples were obtained. Concentrations of elements in the samples were measured in order to identify sources and possible source locations of pollutants. Measured concentrations of trace elements at the &Ccedil<br>andarli station were compared with those measured at various sites around the world and, also in Turkey. As a result of comparison, level of pollution at the Aegean Region was found to be lower than the Mediterranean Region and Black Sea Region. Air flow climatology at &Ccedil<br>andarli was investigated in order to determine potential source regions for pollutants. Frequency of air flows from Russia and Western Europe are higher suggesting that emissions from these industrial regions affect the chemical composition of particulate matter. Besides these, it was concluded that contributions from Central and Eastern European countries are significantly high because of frequent air mass transport. Concentrations of elements measured at &Ccedil<br>andarli station were found to show short and seasonal variations. Such variations in concentrations are explained by variations in the source strengths and transport patterns. Positive matrix factorization (PMF) was applied to determine sources of elements and contribution of sources to each element. This analysis revealed 5 sources, two local anthropogenic emissions factor, one soil factor, one sea salt factor and one long range transport factor. Distribution of Potential Source Contribution Function (PSCF) values showed that main sources of SO42- are observed in Bulgaria, Romania, Poland, Ukraine and central part of Aegean region.

CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior<br>This work was carried out to evaluate the effects of nitrogen fertilization in areas of irrigated pastures with biofertilizados effluents from fish farming. Four doses of nitrogen fertilizer were used for 3 cycles of Tifton-85 grass cut every 28 days and irrigated with wastewater from fish farming. After each cutting the grass was fertilized with the respective doses of fertilizer. The design was completely randomized in a factorial 2 x 4 with four replicates. Four doses of nitrogen fertilizer dose corresponded to 0 to N; 198 kg N ha-1 yr-1 33% of the dose of N; 396 kg N ha-1 yr-1 66% of the dose of N; and 600 kg N ha-1 yr-1 corresponding to 100% of the dose of growth assessment the design was completely randomized using the nitrogen dosages described and four replications. The area per plot was used to harvest the fresh biomass to be analyzed, which was immediately measured on a digital scale pendulum for its determination. After all installments have their biomass values known and properly stored, they were sent to the laboratory of plant analysis Embrapa Mid-North. The collected biomass is fractionated into categories: whole plant (pseudo stem and leaf without senescent material), only pseudoculm, only leaf and senescent material. The stored material was taken for laboratory analysis of animal- nutrition LANA, Federal University Of CearÃ. Analyzes to determine the levels of dry matter were held (MS), mineral matter (MM), ether extract (EE), crude protein (% N x 6.25 = PB). The cellular content of the contents (CC) and hemicellulose (HEM) were obtained following the post- analysis equations. The fiber values of neutral detergent fiber (NDF) and acid detergent fiber (ADF) were measured after preparation of the material to be analyzed in bags of TNT (100 g / m2) with dimensions of 4 x 5cm and engagement in analysis instrument fibers (Ankom220Â). Nitrogen fertilization influenced the soil chemical characteristics as the base saturation and potential soil acidity in Tifton 85 irrigated pasture with fish farm effluents, where nitrogen (N) influenced positively to the growth of Tifton 85 irrigated with wastewater fish farming. Nitrogen fertilization in conjunction with wastewater from fish farming. The absence of nitrogen fertilization promoted increase in dry matter content in Tifton-85 grass, as well as high levels of ADF and NDF. Leaf fraction of Tifton 85 has a higher amount of organic compounds in relation to pseudoculm fraction, and this can change the true values of ether extract and crude protein. The wastewater fish farming along with the application of ammonium sulfate positive effect on the chemical composition of Tifton 85 grass.<br>Este trabalho foi conduzido com o objetivo de avaliar os efeitos da adubaÃÃo nitrogenada em Ãreas de pastagens irrigadas com efluentes biofertilizados oriundos da piscicultura. Quatro doses de adubo nitrogenado foram utilizados durante 3 ciclos do capim Tifton-85, cortado a cada 28 dias e irrigado com Ãgua residuÃria de piscicultura. ApÃs cada corte o capim era adubado com as respectivas doses de adubo. O delineamento utilizado foi inteiramente casualizado em esquema fatorial 2 x 4 com quatro repetiÃÃes. As quatro doses de adubo nitrogenado correspondiam a dose 0 de N; 198 kg de N ha-1 ano-1 33 % da dose de N; 396 kg de N ha-1 ano-1 66% da dose de N; e 600 kg de N ha-1 ano-1 que correspondeu a 100% da dose de N. Para avaliaÃÃo do crescimento o delineamento utilizado foi inteiramente casualizado utilizando as dosagens de nitrogÃnio descritas e quatro repetiÃÃes. A Ãrea da parcela Ãtil foi utilizada para a colheita da biomassa fresca a ser analisada, que foi imediatamente medida em uma balanÃa digital de pendulo para sua determinaÃÃo. ApÃs todas as parcelas terem seus valores de biomassa conhecidos e devidamente armazenados, estes eram encaminhados ao laboratÃrio de analises vegetais da Embrapa Meio-Norte. A biomassa coletada foi fracionada em categorias: planta inteira (pseudocolmo e folha sem o material senescente), somente pseudocolmo , somente folha e material senescente. O material armazenado foi levado para o laboratÃrio de analise de nutriÃÃo animal- LANA, da Universidade Federal Do CearÃ. Foram realizadas anÃlises para determinaÃÃo dos teores de matÃria seca (MS), matÃria mineral (MM), extrato etÃreo (EE), proteÃna bruta (% de N x 6,25 = PB). Os teores do conteÃdo celular (CC) e hemicelulose (HEM) foram obtidos seguindo-se as equaÃÃes pÃs analises. Os valores de fibra em detergente neutro (FDN) e fibra em detergente Ãcido ( FDA), foram mensurados apÃs o acondicionamento do material a ser analisado em saquinhos de TNT (100 g/m2) com dimensÃes de 4 x 5cm e acoplamento em aparelho analisador de fibras (Ankom220Â). A adubaÃÃo nitrogenada influenciou caracterÃsticas quÃmicas do solo como a saturaÃÃo por base e acidez potencial do solo em pastagem de capim- tifton 85 irrigada com efluentes de piscicultura, onde o nitrogÃnio (N) influenciou positivamente para o crescimento do capim-tifton 85 irrigado com efluentes de piscicultura. A adubaÃÃo nitrogenada em conjunto com a Ãgua residuÃria de piscicultura. A ausÃncia de adubaÃÃo nitrogenada promoveu aumento nos teores de matÃria seca no capim tifton-85, assim como elevados teores de FDA e FDN. A fraÃÃo folha do capim tifton 85 possui maior quantidade de compostos orgÃnicos em relaÃÃo a fraÃÃo pseudocolmo, e isso pode alterar os valores verdadeiros de extrato etÃreo e proteÃna bruta. A Ãgua residuÃria de piscicultura junto com a adubaÃÃo nitrogenada proporcionou efeito positivo na composiÃÃo bromatologica do capim Tifton 85.

Pelargonium sidoides DC. is one of many medicinal plant species that are harvested in the wild. The current trade in these medicinal plants has negatively affected their distribution in the wild due to unsustainable harvesting. The demand for medicinal plants is unlikely to decrease, but sustainability of the supply is questionable. This is because commercial exploitation threatens to deplete their populations, resulting in many species being considered vulnerable to extinction and being lost from their natural habitat. Increased demand, which is already too high to be met by sustainable harvesting, and price increases presents potential opportunities for cultivating indigenous medicinal plants at a commercial scale. A need for basic information on how to grow the plants and other related matters necessitates that field trials be conducted, before farmers could be expected to venture into cultivating medicinal plants and this study aimed at developing such information. The specific objectives of the study were to investigate 1) the physiological and morphological, 2) the yield components and 3) chemical composition of P. sidoides in response to soil water and nitrogen levels. The study was conducted under a rainshelter as a randomized complete block design with three irrigation levels, four nitrogen levels and three replicates. The irrigation treatments were 30% allowable depletion level (ADL) (well watered treatment), 50% ADL (moderately stressed treatment) and 70% ADL (severely stressed treatment), while the nitrogen levels were 0, 50, 100 and 150 kg · N · ha-1. Dried root samples were analyzed for the presence of two standard compounds, scopoletin and esculin, using thin layer chromatography (TLC) and for metabolite profiling using the nuclear magnetic resonance technique (NMR). Nitrogen and water level had no significant interaction effect on all measured parameters. Water stress significantly reduced stomatal conductance, while nitrogen had no significant effect on it. The well watered control had a significantly higher leaf area index, plant height and leaf area compared to the water stressed treatments. Nitrogen had a significant effect on the number of leaves, where 100 kg · N · ha-1 had a significantly higher number of leaves compared to other nitrogen treatments. The well watered treatment again had a significantly higher total biomass, fresh and dry root yield; and nitrogen use efficiency compared to the water stressed treatments. The water use efficiency was significantly decreased in the well watered treatment. Water stress significantly increased nitrogen content and chlorophyll content of P. sidoides plants and leaves, respectively. Nitrogen levels of 50 and 100 kg · N · ha-1 resulted in a significantly higher total biomass compared to the control. TLC analysis showed the presence of the two standard compounds in all treatment samples analyzed. The orthogonal partial least square discriminatory analysis (OPLS-DA), which was performed on the NMR spectral data, showed separation between the irrigation treatments, resulting in two clusters representing the well watered treatment and the water stressed treatments. Asparagine, arginine, sucrose, xylose, glucose and citric acid were found to be the compounds associated with the separation. There was no separation of the samples regarding the nitrogen treatments which is indicative of the small effect of nitrogen on the metabolite content of the treatments. The results from this study showed a relationship between physiological, morphological and yield response as well as chemical composition of P. sidoides. The observed stomatal closure under water stress conditions, due to low turgor pressure in the guard cells, had a significant negative effect on leaf area, leaf area index, total biomass and root yield. Also the increases in total biomass and root yield under well watered conditions could be attributed to the increased primary metabolite content, under such conditions. The recommendation from the study is that P. sidoides plants should be grown under well watered conditions for a year or two to increase growth and root yield. Thereafter plants can be exposed to water stress in the second season, which is expected to increase the concentration of important secondary metabolites.<br>Dissertation (MInst Agrar)--University of Pretoria, 2015.<br>tm2015<br>Plant Production and Soil Science<br>MInst Agrar<br>Unrestricted

Flooding effects mineral composition of pasture grasses, but little is known concerning effects on mineral metabolism and fiber digestibility in animals. Experiments were conducted to investigate effects of flooding and Al-nitrilo-triacetate (Al-NTA) on growth, chemical composition and digestibility of annual ryegrass (Lolium multiflorum, L.). Ryegrass was grown in a greenhouse experiment on Bucks silt loam soil with two soil moisture levels (flooding and 80% field capacity) and two Al rates (0 and 135 mg/kg) as Al-NTA. Flooding increased Al, Fe, Cu, Ca and fiber and decreased dry matter yield, Mg, K and Zn concentrations. Treatment with 135 mg/kg Al had no effect on Al in plants, but decreased Ca and P concentrations. Two digestion trials were conducted with meadow voles (Microtus pennsylvanicus) fed forage harvested from the greenhouse experiment. Voles were housed in stainless steel metabolism cages for total collections of feed and feces. A 2-day preliminary, during which voles were fed 100% ryegrass, preceded a 3-day collection period. At the end of the collection period, a blood sample was taken from the animals. Forage grown under flooding increased apparent absorption of Al, and Ca concentration in urine samples. Apparent absorption of Mg and serum Mg were decreased, and dry matter digestibility tended to decrease. Grazing forages produced under flooded conditions would increase potential for outbreaks of grass tetany in animals due to reduced Mg intake and absorption. Altered Mg and Ca metabolism appeared related to Al ingestion. Lowered animal performance could result from reduced DM digestibility.<br>Master of Science

In recent years there has been an increasing awareness of the role and benefits of scientific fish farming in coastal waters for augmenting fish production of India, although a traditional practice of aquaculture has been prevailing in these waters for a long time. A comprehensive knowledge of the ecology of the different culture systems forms an integral part of the scientific farming because it directly influences the rate of production. The growth and survival of the organisms used for culture depend largely on the overall productivity of the pond, which in turn, is influenced by the various environmental characteristics of the water and the fertility of the pond soil. In short, the water and soil conditions to a great extent determine the success or failure of the culture operation. Further, the information on the various environmental characteristics of the pond water and soil, availability of essential elements and the rate of organic productivity, would not only help to adopt successful management principles and culture techniques but also to manipulate the ecosystem providing the necessary inputs for obtaining better production. Besides providing an overall picture of the productivity of the ponds, studies on soils furnish information on the inputs to enhance the fertility of soils and also help in selection of suitable sites for construction of farms.