Soil environments interactions

Furthermore, abiotic and biotic reactions are not independent but rather, interactive processes in soil environments. Interactions of abiotic and biotic processes are thus very important in governing the dynamics and fate of metals and metalloids in soils, especially at the soil-root interface. Abiotic and biotic interactions in the rhizosphere in influencing the stabilization of contaminants and the efficacy of ameliorants need to be investigated. The impact of physical, chemical, and biological interfacial interactions on risk assessment and management of metal and metalloid contamination and restoration of ecosystem health merits close attention. 

Lueders T, B Wagner, P Claus, MW Friedrich (2004a) Stable isotope probing of rRNA and DNA reveals a dynamic methylotroph community and trophic interactions with fungi and protozoa in oxic rice field soil. Environ Microbiol 6 60-72. 

Sulfur in the Environment, edited by Douglas G. Maynard Soil-Machine Interactions A Finite Element Perspective, edited by Jie Shen and Radhey Lai Kushwaha... 

The physicochemical properties of a pesticide and its interaction with soil greatly influences both its mobility and biological a-vailability in a soil environment (1). Reviews on this subject have been published by Goring and Hamaker (2 ) and Greenland and Hayes ( 3). 

Soil is the central organizer of the terrestrial ecosystem. Soil constituents, be they minerals, organic matter, or microorganisms, are of prime importance in governing interactive physical, chemical, and biological processes in soil environments. 

Bacteria and their composites with soil minerals or organic matter are capable of taking up a wide range and variety of toxic metals in soil environments. Research done over the last decade or so has greatly improved our understanding of the mechanisms on biosorption of metals and bacte-ria-metal-soil component interactions. However, more studies from molecular level are needed in order to enhance the ability of bacteria and their association with soil components to remediate toxic metals-contaminated soils. The focus of future investigations should be on the mechanisms by which metals are sorbed and bound by bacterial cell surfaces and bacteria-soil/mineral composites. In this connection, X-ray absorption spectroscopy (XAS) is a promising technique because it can provide information about... 

Substance Complexes in Soil. Dr. P. M. Huang from University of Saskatchewan, Canada, who was the founder of Working Group MO and the founding Chair of Commission 2.5 of IUSS, gave a plenary lecture on Physical-Chemical-Biological Interfacial Interactions in Soil Environments. 

James, B.R. and R.J. Bartlett. 1983b. Behavior of chromium in soils. VI. Interactions between oxidation-reduction and organic complexation. Jour. Environ. Qual. 12 173-176. 

Nematodes play a major role in decomposition and nutrient cycling in soil food webs. Due to its important role in trophic interactions, they have received attention in farming systems especially in organic farming. Although nematodes represent a relatively small amount of biomass in soil, their presence across many trophic levels in soils is vitally important in soil environments and ecosystem processes (Ingham et al. 1986). 

The secretion of secondary metabolites to the apoplast is another way to circumvent the toxic effects of some plant natural products. Plants use this mechanism especially in root cells. Then, they can interact with neighboring plants (allelopathy) or modify soil environment to promote... 

Alkaloids from many plants are considered to be used as biological fertilizers in ecological cultivation. This is very important especially in cases when more attention is given to these plants, which play not only a role in production but also in the cyclical maintenance of a field, garden or forest ecosystems . Plants containing alkaloids, for example lupines, have the ability to establish complexes with the soil and with the rhizosphere. The excretion of many chemicals from roots to soil occurs in this complex. Plant mediation with the soil environment is the result. The alkaloids play a major role in this plant-soil interaction system. 

The soil environment is a dynamic one which includes gas, liquid, and solid phases. It is imperative in any soil bioremediation process to have a clear understanding of these phases and how they interact. This includes not only the chemical characteristics of soil colloids, but the physical arrangement of components. The first section is meant as a brief introduction to soil chemical and physical properties and is intended primarily for those unfamiliar with the area. 

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