N cycle: What is assimiatory uptake and dissimilatory transformation? How can a stream remove N?

Assimilatory (der hvor den optager N) og Dissimilatory (der hvor den bruger det i en elektrontransportkæde). Dissimilatory = nitrification and denitrification. Denitrification is the only process that removes nitrogen from the stream. Happens in areas areas with slow moving water (no oxygen) or deeper in the sediment. Can also happen in thiick biofilm because there can be anoxic conditions. Indirect nitrification - det har lige været en tur igennem en mikroorganisme først. Direct betyder at det ikke har været assimileret først.