Abstract
The river plankton - potamoplankton - consists predominantly of autochthonous as well as allochthonous elements and it is poorly represented in rivers due to the water flow. The allochthonous elements that reach streams from stagnant waters suffer changes or, if they cannot adapt to the environment, quickly die. Usually, in a current stronger than 1 m/s they do not survive. Potamoplankton variety increases from spring to effusion, plankton being almost completely absent in the region of the spring.
In medium and small basins, places with stagnant water are formed and plankton growth is supported, but in areas where there are no crossings and water speed is too high, plankton is destroyed due to mechanical action.
In rivers, phytoplankton mainly consists of diatoms, chlorophytes, euglenophytes and cyanobacteria, etc.
The aquatic environment is wide, having various physico-chemical characteristics which determine different ecological conditions, so that the distribution of aquatic animals and plants differs.
Aquatic ecosystems are structural and functional units consisting of biotopes and biocenosis that support self-integrated activities, the result being biological production and destruction.
Timiş River was monitored in 2012 in the months of May and September in the Lugoj, Hitiaș, Şag and Grăniceri sections. Also pH was monitored for oxygen and the nutrient flow of these sectors and interpretations and correlations of the phytoplankton quality indicators were made.