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Mineralization (soil Science)
Mineralization in soil science is the decomposition (i.e., oxidation) of the chemical compounds in organic matter, by which the nutrients in those compounds are released in soluble inorganic forms that may be available to plants. Mineralization is the opposite of immobilization. Mineralization increases the bioavailability of the nutrients that were in the decomposing organic compounds, most notably, because of their quantities, nitrogen, phosphorus, and sulfur. Whether the decomposition of an organic compound will result in mineralization or immobilization is dependent on its concentration proportionate to that of the carbon in the organic matter. As a rule of thumb, if the concentration of a specific element exceeds the needs of the decomposer for biosynthesis or storage, then it will mineralize. Ratio of carbon to nitrogen Whether nitrogen mineralizes or immobilizes depends on the carbon-to-nitrogen ratio (C:N ratio) of the decomposing organic matter.R.G. McLaren & K. Cam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soil Science
Soil science is the study of soil as a natural resource on the surface of the Earth including soil formation, classification and mapping; physical, chemical, biological, and fertility properties of soils; and these properties in relation to the use and management of soils.Jackson, J. A. (1997). Glossary of Geology (4. ed.). Alexandria, Virginia: American Geological Institute. p 604. Sometimes terms which refer to branches of soil science, such as pedology (formation, chemistry, morphology, and classification of soil) and edaphology (how soils interact with living things, especially plants), are used as if synonymous with soil science. The diversity of names associated with this discipline is related to the various associations concerned. Indeed, engineers, agronomists, chemists, geologists, physical geographers, ecologists, biologists, microbiologists, silviculturists, sanitarians, archaeologists, and specialists in regional planning, all contribute to further knowledge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonium
The ammonium cation is a positively-charged polyatomic ion with the chemical formula or . It is formed by the protonation of ammonia (). Ammonium is also a general name for positively charged or protonated substituted amines and quaternary ammonium cations (), where one or more hydrogen atoms are replaced by organic groups (indicated by R). Acid–base properties The ammonium ion is generated when ammonia, a weak base, reacts with Brønsted acids (proton donors): :H+ + NH3 -> H4 The ammonium ion is mildly acidic, reacting with Brønsted bases to return to the uncharged ammonia molecule: : H4 + B- -> HB + NH3 Thus, treatment of concentrated solutions of ammonium salts with strong base gives ammonia. When ammonia is dissolved in water, a tiny amount of it converts to ammonium ions: :H2O + NH3 OH- + H4 The degree to which ammonia forms the ammonium ion depends on the pH of the solution. If the pH is low, the equilibrium shifts to the right: more ammonia molecules are co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soil Chemistry
Soil chemistry is the study of the chemical characteristics of soil. Soil chemistry is affected by mineral composition, organic matter and environmental factors. In the early 1850s a consulting chemist to the Royal Agricultural Society in England, named J. Thomas Way, performed many experiments on how soils exchange ions, and is considered the father of soil chemistry. Other scientists who contributed to this branch of ecology include Edmund Ruffin, and Linus Pauling. History Until the late 1960s, soil chemistry focused primarily on chemical reactions in the soil that contribute to pedogenesis or that affect plant growth. Since then, concerns have grown about environmental pollution, organic and inorganic soil contamination and potential ecological health and environmental health risks. Consequently, the emphasis in soil chemistry has shifted from pedology and agricultural soil science to an emphasis on environmental soil science. Environmental soil chemistry A knowledge of en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Remineralisation
In biogeochemistry, remineralisation (or remineralization) refers to the breakdown or transformation of organic matter (those molecules derived from a biological source) into its simplest inorganic forms. These transformations form a crucial link within ecosystems as they are responsible for liberating the energy stored in organic molecules and recycling matter within the system to be reused as nutrients by other organisms. Remineralisation is normally viewed as it relates to the cycling of the major biologically important elements such as carbon, nitrogen and phosphorus. While crucial to all ecosystems, the process receives special consideration in aquatic settings, where it forms a significant link in the biogeochemical dynamics and cycling of aquatic ecosystems. Role in biogeochemistry The term "remineralization" is used in several contexts across different disciplines. The term is most commonly used in the medicinal and physiological fields, where it describes the develo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrogen Cycle
The nitrogen cycle is the biogeochemical cycle by which nitrogen is converted into multiple chemical forms as it circulates among atmospheric, terrestrial, and marine ecosystems. The conversion of nitrogen can be carried out through both biological and physical processes. Important processes in the nitrogen cycle include fixation, ammonification, nitrification, and denitrification. The majority of Earth's atmosphere (78%) is atmospheric nitrogen, making it the largest source of nitrogen. However, atmospheric nitrogen has limited availability for biological use, leading to a scarcity of usable nitrogen in many types of ecosystems. The nitrogen cycle is of particular interest to ecologists because nitrogen availability can affect the rate of key ecosystem processes, including primary production and decomposition. Human activities such as fossil fuel combustion, use of artificial nitrogen fertilizers, and release of nitrogen in wastewater have dramatically altered the global nitr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrification
''Nitrification'' is the biological oxidation of ammonia to nitrite followed by the oxidation of the nitrite to nitrate occurring through separate organisms or direct ammonia oxidation to nitrate in comammox bacteria. The transformation of ammonia to nitrite is usually the rate limiting step of nitrification. Nitrification is an important step in the nitrogen cycle in soil. Nitrification is an aerobic process performed by small groups of autotrophic bacteria and archaea. Microbiology Ammonia oxidation The oxidation of ammonia into nitrite (also known as nitritation) is performed by two groups of organisms, ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA). AOB AOB can be found among the Betaproteobacteria and Gammaproteobacteria. Since discovery of AOA in 2005, two isolates have been cultivated: ''Nitrosopumilus maritimus'' and ''Nitrososphaera viennensis''. In soils the most studied AOB belong to the genera ''Nitrosomonas'' and '' Nitrococcus''. AOA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mineral Matter In Plants
Plant nutrition is the study of the chemical elements and compounds necessary for plant growth and reproduction, plant metabolism and their external supply. In its absence the plant is unable to complete a normal life cycle, or that the element is part of some essential plant constituent or metabolite. This is in accordance with Justus von Liebig’s law of the minimum. The total essential plant nutrients include seventeen different elements: carbon, oxygen and hydrogen which are absorbed from the air, whereas other nutrients including nitrogen are typically obtained from the soil (exceptions include some parasitic or carnivorous plants). Plants must obtain the following mineral nutrients from their growing medium: * the macronutrients: nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), sulfur (S), magnesium (Mg), carbon (C), oxygen (O), hydrogen (H) * the micronutrients (or trace minerals): iron (Fe), boron (B), chlorine (Cl), manganese (Mn), zinc (Zn), copper (Cu), mol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Humus
In classical soil science, humus is the dark organic matter in soil that is formed by the decomposition of plant and animal matter. It is a kind of soil organic matter. It is rich in nutrients and retains moisture in the soil. Humus is the Latin word for "earth" or "ground". In agriculture, "humus" sometimes also is used to describe mature or natural compost extracted from a woodland or other spontaneous source for use as a soil conditioner. It is also used to describe a topsoil horizon that contains organic matter (''humus type'', ''humus form'', or ''humus profile''). Humus has many nutrients that improve the health of soil, nitrogen being the most important. The ratio of carbon to nitrogen (C:N) of humus commonly ranges between eight and fifteen with the median being about twelve. It also significantly affects the bulk density of soil. Humus is amorphous and lacks the "cellular cake structure characteristic of plants, micro-organisms or animals". Description The primary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Humification
In classical soil science, humus is the dark organic matter in soil that is formed by the decomposition of plant and animal matter. It is a kind of soil organic matter. It is rich in nutrients and retains moisture in the soil. Humus is the Latin word for "earth" or "ground". In agriculture, "humus" sometimes also is used to describe mature or natural compost extracted from a woodland or other spontaneous source for use as a soil conditioner. It is also used to describe a topsoil horizon that contains organic matter (''humus type'', ''humus form'', or ''humus profile''). Humus has many nutrients that improve the health of soil, nitrogen being the most important. The ratio of carbon to nitrogen (C:N) of humus commonly ranges between eight and fifteen with the median being about twelve. It also significantly affects the bulk density of soil. Humus is amorphous and lacks the "cellular cake structure characteristic of plants, micro-organisms or animals". Description The primary m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Decomposition
Decomposition or rot is the process by which dead organic substances are broken down into simpler organic or inorganic matter such as carbon dioxide, water, simple sugars and mineral salts. The process is a part of the nutrient cycle and is essential for recycling the finite matter that occupies physical space in the biosphere. Bodies of living organisms begin to decompose shortly after death. Animals, such as worms, also help decompose the organic materials. Organisms that do this are known as decomposers or detritivores. Although no two organisms decompose in the same way, they all undergo the same sequential stages of decomposition. The science which studies decomposition is generally referred to as ''taphonomy'' from the Greek word ''taphos'', meaning tomb. Decomposition can also be a gradual process for organisms that have extended periods of dormancy. One can differentiate abiotic decomposition from biotic decomposition (biodegradation). The former means "the degradation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Cycle
The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and Earth's atmosphere, atmosphere of the Earth. Carbon is the main component of biological compounds as well as a major component of many minerals such as limestone. Along with the nitrogen cycle and the water cycle, the carbon cycle comprises a sequence of events that are key to make Earth capable of sustaining life. It describes the movement of carbon as it is recycled and reused throughout the biosphere, as well as long-term processes of carbon sequestration to and release from carbon sinks. Carbon sinks in the land and the ocean each currently take up about one-quarter of anthropogenic carbon emissions each year. Humans have disturbed the biological carbon cycle for many centuries by modifying land use, and moreover with the recent industrial-scale mining of fossil carbon (coal, petroleum and natural gas, gas extraction, and cement manufacture) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catabolism
Catabolism () is the set of metabolic pathways that breaks down molecules into smaller units that are either oxidized to release energy or used in other anabolic reactions. Catabolism breaks down large molecules (such as polysaccharides, lipids, nucleic acids, and proteins) into smaller units (such as monosaccharides, fatty acids, nucleotides, and amino acids, respectively). Catabolism is the breaking-down aspect of metabolism, whereas anabolism is the building-up aspect. Cells use the monomers released from breaking down polymers to either construct new polymer molecules or degrade the monomers further to simple waste products, releasing energy. Cellular wastes include lactic acid, acetic acid, carbon dioxide, ammonia, and urea. The formation of these wastes is usually an oxidation process involving a release of chemical free energy, some of which is lost as heat, but the rest of which is used to drive the synthesis of adenosine triphosphate (ATP). This molecule acts as a way f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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