Original paper

Mineralization of phycodetritus in riverine water

Starzecka, Aleksandra; Bednarz, Teresa


In the polluted water of the Wilga River (an east tributary of the Vistula River upper course) and the clean water of the Rudno Stream (a west tributary of the Vistula River upper course) the rate of mineralization of the phycodetritus of Chlorella pyrenoidosa and Scenedesmus quadricauda added to the water was investigated in 94 and 64 hrs experiments. The greatest rate of mineralization of the mass of Chlorella was found between 28 and 36 hr of the experiments and amounted 0.21 mg dm-3 h-1 of C at an algal treatment level of algae 56.7 mg dm-3 C and 0.11 mg dm-3 h-1 C at the dose 17.0 mg dm-3 C. At the high treatment level of the Chlorella detritus at the end of experiment (94 hrs), and at the low treatment level 18% and 26% of detritus respectively were mineralized. According to a linear model of regression, the total time of the mineralization of the phycodetritus followed after about 17 and 14 days at high and low treatment levels of Chlorella respectively. In spite of the differences shown in the rate of CO 2release from Chlorella and Scenedesmus detritus, the quantity decomposed after 64 hrs of the experiment was very similar. In the water of the polluted Wilga River, mineralization of phycodetritus was mainly bacterial, but in the non-polluted water of the Rudno Stream bacterial mineralization of the added phycodetritus played a decidedly less important role.


chlorellascenedesmusphycodetritusmineralizationrunning water