A large store of a nutrient at some stage in a biogeochemical cycle. Reservoir pools are mainly abiotic, but may also be biotic, as in the case of the biomass of a forest, which represents a considerable store of various elements, especially carbon. Exchanges between the reservoir pool and the active pool are typically slow by comparison with exchange within the active pool. Human activity, such as the mining of mineral resources and the manufacture and application of fertilizer, may profoundly alter this exchange rate, generally releasing an excess into the active pool which can be accommodated only by establishing a new equilibrium. This may in turn produce unfavourable conditions, manifested as chemical pollution (e.g. excess phosphorus in eutrophication, excess sulphur in acid precipitation and lake acidification).
Subjects: Plant Sciences and Forestry — Ecology and Conservation.