The need for comprehensive and consistent treatment of the nitrogen cycle in nitrogen cycling and mass balance studies: I. Terrestrial nitrogen cycle
| Autor: | D. Winstanley, E.C. Krug |
|---|---|
| Rok vydání: | 2002 |
| Předmět: |
Biogeochemical cycle
Time Factors Environmental Engineering Geography Nitrogen Earth science media_common.quotation_subject Biogeochemistry Models Theoretical Pollution Conceptual model Environmental Chemistry Terrestrial ecosystem Physical geography Cycling Temporal scales Waste Management and Disposal Nitrogen cycle Ecosystem Environmental Monitoring Hydrosphere media_common |
| Zdroj: | Science of The Total Environment. 293:1-29 |
| ISSN: | 0048-9697 |
| DOI: | 10.1016/s0048-9697(01)01133-0 |
| Popis: | A review of conceptual models that scientists use to characterize the nitrogen (N) cycle and to conduct N mass balance studies at global, regional and local scales is presented. Large uncertainties in processes and process rates make it difficult to conduct precise N mass balances and the dominant conceptual model has changed in recent decades. An earlier conceptual model recognized explicitly that human activities, especially agriculture, have both depleted terrestrial N and increased the fixation of atmospheric N in biologically available forms. The current conceptual model does not include adequate treatment of the depletion of the terrestrial N reservoir, the resulting transfer of N to the hydrosphere and atmosphere, or the cycling of terrestrial N below the plow layer. Thus, it delivers an unrealistically limited view of human influences on the N cycle. It is recommended that a comprehensive and consistent treatment of terrestrial N cycling be developed to better facilitate scientific explanation of historical N-related environmental changes and more closely balance N budgets on a range of geographical and temporal scales. Improved N-cycle models will provide an improved scientific basis for answering important resource management and policy questions. |
| Databáze: | OpenAIRE |
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