Transformations of C, N, P in lotic-lentic transition

The transformation of organic matter in lentic and lotic conditions are dominated by different processes. The special attention deserves the transition from riverine to lacustrine conditions. In our experiment we incubated the stream and pond water inside of mesocosms in the small forest ponds for 28 days. That time was previously observed as sufficient for the reestablishing of chemical and biological processes after severe rain events in the same pond. We aimed to evaluate the dynamics in organic matter, nitrogen, and phosphorus concentrations, fractioning between particulate and dissolved forms, as well as the development of microbial community. Additionally, we tested the influence of presence and absence of solar radiation in one experiment and the effect of different transparency of surrounding environment. The observed changes in C, N, and P fluxes were simulated by the first order kinetics model. The slowest processes were observed in dark mesocosms with the highest initial color and organic carbon content, while the light exposed and less colorful mesocosms revealed fastest rates.