Biogeochemical Characteristics

Wetlands can be very diverse with very high internal spatial heterogeneity with respect to vegetation, soils, and hydrology. Thus, the characteristics and functions of any given wetland can be determined by the position on the landscape, climate, hydrology, vegetation, and soils. 

Definition Land or areas (such as tidal flats or swamps) containing much soil moisture. Source  

Estimated Economic Value of Selected Ecosystems of the Biosphere 

Definition Wetlands are lands transitional between terrestrial and aquatic systems where the water table is usually at or near the surface or the land is covered by shallow water. For purposes of this classification, wetlands must have one or more of the following three attributes (i) at least periodically, the land supports predominately hydrophytes, (ii) the substrate is predominately undrained hydric soil, and (iii) the substrate is nonsoil and is saturated with water or covered by shallow water at some time during the growing season of each year. Source Cowardin et al. (1979). U.S. Department of Interior—Fish and Wildlife Service. This definition places emphasis on all three major attributes of wetlands, and is difficult to apply as it requires a comprehensive study of the site. The boundaries identified by this criteria are much more reliable than the EPA definition. 

FIGURE 3.1 (a) Wetlands shown as a continnnm between terrestrial and deepwater aqnatic systems, (b) Wetlands can exist as isolated from other water bodies. (From Mitsch and Gosselink, 2000. With permission.) 

---

Specific biogeochemical characteristics define the Ebro Delta. This area receives the impacts of the activities on the whole river basin. Before the dam construction... 

The fate of HOCs and overall dynamics of their potential equilibrium partitioning has also been shown to be affected by the biogeochemical characteristics of the sorbing matrix as well as inherent differences in HOCs. For example, higher concentrations of... 

Lobbes J. M., Fitznar H. P., and Kattner G. (2000) Biogeochemical characteristics of dissolved and particulate organic matter in Russian rivers entering the Arctic Ocean. Geochim. Cosmochim. Acta 64, 2973-2983. 

Compare the biological and biogeochemical characteristics of Tundra and Polar ecosystems. Explain the role of climate and soil chemical composition in the formation of biogeochemical turnover in Tundra ecosystems. 

Table 6.3 Selected biogeochemical characteristics of sediments at three sites of Indo-German sediment traps (WAST - Western Arabian Sea Trap CAST - Central Arabian Sea Trap SAST -Southern Arabian Sea Trap) - after Pfannkuche and Lochte (2000)...

---