The nitrogen cycle is the biogeochemical cycle by which nitrogen is converted into multiple chemical forms as it circulates among atmosphere, terrestrial, and marine ecosystems. ... Important processes in the nitrogen cycle include fixation, ammonification, nitrification, and denitrification.
Answer:
availability of resources.
Explanation:
Availability of resources is abiotic factor which is responsible for the decrease in population in 1990 because when the population reaches its carrying capacity so the organisms compete with each other and due to limited resources such as food etc the decrease occurs in population. Infection is also occurs when there is high population due to which death occurs and population of organism decreases.
Well fungi usually feed off of the decomposing matter of dead creatures and nutrients around it, while animals usually feed off plants or living things. fungi is a decomposer while animals are just consumers.
