Abiotic retention

Phosphorus sorption refers to the abiotic retention of inorganic phosphorus in soils. In the following text, we will review few concepts and terminology related to inorganic phosphorus retention in soils. For details on the terminology, the reader is referred to basic soil chemistry textbooks (e.g., McBride, 1994 Bohn et al., 1985). 

The sorption process (abiotic retention) is controlled by the concentration of phosphate in soil pore water and the ability of the solid phase to replenish phosphate into pore water. This can be described in terms of two regulating factors The intensity factor of the sorption process is controlled by the concentration of phosphate in soil pore water, and the capacity factor refers to the ability of the solid phase to replenish phosphate to the soil pore water. 

Multiple, dynamic roles of microbial and plant rhizosphere biotic processes on abiotic retention of elements in wetlands. 

The fate of triazine herbicides in soils is controlled by three basic processes transformation, retention, and transport. This chapter focuses primarily on soil properties and processes that influence retention. While transformation includes both biological and abiotic decomposition, only abiotic processes are covered in this chapter. 

A corollary is that almost all stressors leave lasting impacts and that the information is located in a variety of biotic and abiotic components. The hypothesis states that ecological structures are historical, unique, and complex. The hypothesis explicitly recognizes the importance of indirect effects in retention of information within systems and in impacting the outcomes of future stressor events. These features place community conditioning in opposition to equilibrium-based or threshold models prevalent in ecological risk assessment and environmental toxicology. 

A wetland is composed of water, substrate, plants, plant litter, invertebrates (mostly insect larvae and worms), and microorganisms (Halverson, 2004). Processes controlling contaminant retention in the aquatic system sediment may be abiotic (physical and chemical) or biotic (microbial and botanical) and are often interrelated (USDA, 1995 ITRC, 2003), (Fig. 1). 

Abiotic phosphorus retention by wetland soils is regulated by various physicochemical properties including pH, redox potential, iron, aluminum, and calcium content of soils, organic matter content, phosphorus loading, and ambient phosphorus content of soils. 

Bioconcentration refers to the passive partitioning of a xenobiotic between an abiotic environmental medium and a living organism. Bioaccumulation desaibes the uptake and retention of a xenobiotic from all sources, biotic (prey) as well as abiotic. Bioaccumulation depends on the same phenomenon as bioconcentration The rate at which an organism takes up a xenobiotic exceeds the rate at which the organism is able to eliminate it As a result, more chemical enters the body than leaves it per unit time. 

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