Ecological efficiency
ecological efficiency of an ecosystem refers to the effectiveness, with which it maintains its dynamic nature. The effectiveness is usually expressed as energy ratios. These ratios express the efficiency with which organisms exploit their food resources and convert the food into biomass.
Commonly, such ratios are calculated by relating output to input of energy both expressed in same units) at various points along pathways of energy flow.
These ratios are multiplied with 100 to express the efficiency as percentage. At the level of producer, the photosynthetic efficiency and net production efficiency represent ecological efficiency.
Photosynthetic Efficiency
The photosynthetic efficiency measures the ability to utilise the solar energy, falling on the producers.
This efficiency is also expressed in relation to photosynthetically active radiations or PAR (i.e., Visible radiations with wavelength, ranging between 400nm to 700 nm).
Net Production Efficiency
Net production efficiency reflects the effectiveness with which the energy 1s being converted into biomass. It varies widely amongst different species.
Assimilation Efficiency
Assimilation efficiency is the percentage of food energy taken into the guts of consumers in a trophic compartment (In) that is assimilated across the gut wall (A„) and becomes available for incorporation into growth or to do work. The remainder is lost as feces and enters the base of the decomposer system.
These efficiencies are computed as shown in following formula :-
Gross primary productivity x 100
Photosynthetic efficiency= ———————————————
Total incident solar radiations
Net primary productivity x 100
Net production efficiency= ————————————————–
Gross primary productivity
Food energy assimilated x 100
Assimilation efficiency = ——————————————–
Food energy ingested
Energy in biomass production att a trophic level x 100
Ecological efficiency = ——————————————————————————–
Energy in biomass production at previous trophic