Dynamics of biomass and dead organic material in various habitats
The plant sector models conversion of inorganic carbon and nutrients into specific forms of biomass, and provides linkages to the hydrology through evapotranspiration. It includes both photosynthetic and non-photosynthetic biomass components. Maximum uptake rates are derived from empirical data relative to seasonal temperatures. During the simulation, maximum uptake rates are limited by light, nutrient concentrations and water availability. The resultant uptake quantity is derived by multiplying the resultant uptake rate by the total photosynthetic potential (total leaf area).
The maximum attainable leaf area is habitat specific, and derived empirically as a proportion of the total biomass. Biomass and nutrients are accounted for in both above and below ground material. Once the optimum leaf to biomass ratio is reached during plant growth, excess biomass is routed to the non-photosynthetic component. The increase of total biomass allows additional increases in photosynthetic biomass. The non-photosynthetic biomass feeds back into the photosynthetic part by means of early spring sap flows in deciduous trees and through seed germination.
Total macrophyte biomass decreases through respiration, mortality and consumption by consumers. As consumers harvest macrophytes, their biomass increases and they accelerate the mineralization of nutrients through digestion and shredding of detrital matter. "Consumers" are part of a larger cycle of material fluxes and represent an aggregation of the total food web associated with a particular habitat category. Consumer biomass is lost to respiration and mortality. Macrophyte and consumer mortality provide inputs to detrital matter. Detrital matter is lost to the deposited organic matter (DOM) through shredding. The final removal of organic carbon from the ecosystem is through DOM decomposition.
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| Unity Subwatershed | Cattail Subwatershed |
The same output at a 10 day time step and different color scaling
