Biota mineralization

Bioavailability of Metals, Nonmetals and Xenobiotics Immobilized on Soil Components, (4) Distribution and Activity of Biomolecules in Terrestrial Systems, (5) Interactions between Soil Microbial Biomass and Organic Matter/Nutrient Transformations, and (6) Impact of Interactions among Soil Mineral Colloids, Organic Matter and Biota on Risk Assessment and Restoration of Terrestrial Ecosystems. There were 2 plenary lectures, 9 invited speakers, 36 oral presentations and 45 posters. Dr. N. Senesi from University of Bari, Italy, presented an IUPAC lecture entitled Metal-Humic... 

The speciation and physicochemical state of nickel is important in considering its behavior in the environment and availability to biota. For example, the nickel incorporated in some mineral lattices may be inert and have no ecological significance. Most analytical methods for nickel do not distinguish the form of nickel the total amount of nickel is reported, but the nature of the nickel compounds and whether they are adsorbed to other material is not known. This information, which is critical in determining nickel s lability and availability, is site specific. Therefore, it is impossible to predict nickel s environmental behavior on a general basis. 

Kelly, M. G. 1999. Effects of heavy metals on the aquatic biota. In Pujmlee, G. S. Logsdon, M. J. (eds) The Environmental Geochemistry of Mineral Deposits. Pan A Processes, Techniques... 

Moreover, both river induced up-welling and river discharge of nutrients create a fertile environment which enhances the primary production of organic matter in off-shore direction of estuaries. It can be predicted from these observations that heterogeneous reactions between dissolved and both mineral phase and biota will be predominant in estuaries and coastal zones. These reactions will primarily affect those elements and compounds which are located at the particulate surface. The determination of surface properties of particles appear to be an important key to understand the interactions of trace elements and organic compounds between particulate and dissolved phases in estuarine and coastal systems. 

Only a fraction of the total metal content of soils and sediments tends to be available for uptake by plants or biota. This fraction is generally associated with the colloidal material (i.e., clay minerals, hydrous oxides and organic matter), but views differ on the relative effects of the individual components. 

Soil and related environments are both an important natural habitat of biota and a natural reservoir of biotic debris consisting of plant remains and dead animals and microorganisms. With time, dead remains are subject to continuous turnover, either mineralized or transformed to diverse organic components which are termed humus. This process is referred to as humification. Humus is composed of humic substances plus nonhumic substances that have become stabilized and are thus an integral part of soil and related environments (Table 2.1). 

The natural sources of soil organic matter (SOM) are indigenous plant and animal debris that are decomposed and partly mineralized by soil biota. Any factor that... 

Mineralization, Separation, and Electrolysis of55Fe in Aquatic Sediment and Biota Samples... 

Sr is one of the most hazardous and dangerous radioactive isotopes. It is a pure beta emitter (Eimj = 546 keV) and decays to another pure beta emitter, 90Y ( max = 2283.9 keV).10 The radiochemical methods for determining 90Sr in aquatic samples (water, sediment, and biota) are based on the adsorption of radiostrontium on AMP in water samples, mineralization of sediment and biota, and sorption on Sr resin.14 16... 

Sediments deposited in Flodelle Creek spring pool and the Great Lakes have similar and relatively uncomplicated sulfur geochemistry that is controlled by two processes. These processes are the assimilation of sulfur into living biota and its subsequent deposition as organosulfur when the organism dies, and the complete reduction of the pore-water sulfate to H2S that forms sulfide minerals. Low dissolved sulfate concentrations limit the amount of sulfide minerals formed. The 834S value of most of the Smin is essentially the same as the dissolved sulfate. The possible exceptions are minerals formed in sediment from which some 34S-depleted H2S had diffused. 

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