Microbial processes within the nitrogen cycle

Abstract

Biological processes within the nitrogen cycle in Lake Kinneret are mediated by microbial populations and seasonally and spatially divided. Changes in stratification, dissolved inorganic nitrogen (DIN), and O2 concentration in the epilimnion and hypolimnion of the lake (internal factors), in addition to external sources such as input of nitrate and organic N via the Jordan River and atmospheric deposition, all have an impact on microbial diversity and activity. Assimilation, nitrification, denitrification, ammonification, and N2 fixation are the main processes mediated by microbial populations in Lake Kinneret. Large temporal variations in the nitrogen isotopic composition (δ15N) of particulate organic matter (POM) and DIN species in Lake Kinneret occurred in response to the dominant nitrogen cycle processes.