Energy enters as light energy, or photons, is transformed into chemical energy in organic molecules by photosynthesis.
Energy is dissipated
Plants obtain elements from the surrounding atmosphere, water, or soils.
Animals obtain elements from other organisms.
Due to excretion or decomposition, elements returned to an inorganic state.
Materials are not destroyed or lost- closed system with respect to elements
Indicates available solar energy
Gives information about minerals
Inter-relationship of organism
To know about conservation of resources, GPP and NPP
Biological Survey, Crop rotation