population

community

ecosystem

habitat

biotic factors

abitotic Factors

interdependence

pollution

population density

trophic level

parasitism

mutualism

quadrat

belt transect

random sampling

biomass

producer

consumer

detrivore

bio-diversity

non-indigenous species

indigenous species

eutrophication

conservation

reforestation

food security

pest

pathogen

biofuel

decomposers

potable water

desalination

indicator species