Terrestrial Ecosystem Model

Joos F., Prentice I. C., and House J. I. (2002) Growth enhancement due to global atmospheric change as predicted by terrestrial ecosystem models consistent with US forest inventory data. Global Change Biol. 8, 299-303. 

The most common way in which the global carbon budget is calculated and analyzed is through simple diagrammatical or mathematical models. Diagrammatical models usually indicate sizes of reservoirs and fluxes (Figure 1). Most mathematical models use computers to simulate carbon flux between terrestrial ecosystems and the atmosphere, and between oceans and the atmosphere. Existing carbon cycle models are simple, in part, because few parameters can be estimated reliably. 

Potter, C. S., Randerson, J. T., Field, C. B., Matson, P. A., Vitousek, P. M., Mooney, H. A. and Klooster, S. A. (1993). Terrestrial ecosystem production A process model based on global satellite and surface data. Global Biogeochem. Cycles 7, 811-841. 

A global representation of the P cycle, by necessity, will be general. It will combine a wide variety of P-containing components into relatively few reservoirs and will parameterize intricate processes and feedback mechanisms into simple first-order transfers. To appreciate the rationale behind the construction of such a model and to understand its limitations, the transfers of P within a hypothetical terrestrial ecosystem and in a generalized ocean system will be discussed first. 

On the other hand, reservoirs are ecosystems strongly linked with the surrounding terrestrial ecosystems, and it is hardly useful to model them independently. 

Huff, D.D. et al. (1977). TEHM A terrestrial ecosystem hydrology model. Oak Ridge National Laboratory, Oak Ridge, TN. 

Figure 3. General model of bio geo chemical cycles in the Earth s ecosystems. The left part is bio geochemical cycling in terrestrial ecosystems, the right part is aquatic ecosystems and the central part is connected with the atmosphere. The fine solid lines show the biogeochemical food webs (the Latin numbers I-XXI) and directed and reverse relationships between these...

Terrestrial ecosystems. The simplest model used in terrestrial ecosystems is based on the simplified food chain ... 

Similar to terrestrial ecosystems, no distinction is made between various oxidation states of the metals. This assumption seriously limits the application of the model to calculate critical loads for mercury. 

Disturbance of Phosphorus Biogeochemical Cycle in Agrolandscapes Conceptual ideas behind simulation of P cycling are related to construction of models for freshwater terrestrial ecosystems and a generalized oceanic system and understanding the restrictions of its application. 

To make adequate environmental policies concerning a reduction of the emission of POPs, the risks resulting from the deposition of POPs should be estimated. For that purpose some models to assess the risks of POPs in terrestrial ecosystems have been created (Bakker et al., 1998). The most important step of the approaches is developing models for computation of POP concentrations in soil from the data of their load on the land surface (see section 1). Based on these results, the estimating environmental risk from POPs accumulation in the soil compartment was carried out (Vasilyeva and Shatalov, 2004). 

A Terrestrial-Aquatic Model Ecosystem for Evaluating the Environmental Fate of Drugs and Related Residues in Animal Excreta... 

When farm animals are treated with drugs both as a prophylactic or curative measure, majority of the drug or drug related residues are eliminated in the excreta. Poultry as well as farm animal excreta is allowed to compost into manure and the manure is used on the farm land. The objective of the present study was to design a terrestrial-aquatic model ecosystem for evaluating the environmental fate of drugs and related residues in the animal excreta used as manure. 

The modified terrestrial-aquatic model ecosystem described here has been found to be a useful tool in studying the environmental fate of drugs and related residues present in animal excreta used as manure. The operation of the ecosystem is relatively simple and yet it allows one to study the complex metabolic transformations of a drug or related residues in its various components. Especially interesting is the study of the degradation of a compound in the soil in the presence of microorganisms found in the animal excreta. This information is important since it eventually determines whether a compound and/ or its metabolites will bioaccumulate in the various elements of the environment. 

Neff, J. C., and G. Asner. 2001. Dissolved organic carbon in terrestrial ecosystems Synthesis and a model. Ecosystems 4 29—48. 

Thornton, P. E., and Rosenbloom, N. A. (2005). Ecosystem model spin-up Estimating steady state conditions in a coupled terrestrial carbon and nitrogen cycle model. Ecol. Modelling 189, 25 18. 

Chen W. Chen J. and Cihlar J. (2000). An integrated terrestrial ecosystem carbon-budget model based on changes in disturbance, climate, and atmospheric chemistry. Ecological Modelling, 135(1), 55-79. 

Lin D.-L. Sakoda A. Shibasaki R. Goto N. and Suzuki M. (2000). Modelling a global biogeochemical nitrogen cycle in terrestrial ecosystems. Ecological Modelling, 135(1), 89-110. 

Surface water biodegradation t,/2 < 20 d in water and sediment with flooded soils and terrestrial-aquatic model ecosystems (Muir 1991). 

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