title

Research for the Environment

German

Ecological Water Treatment Technologies (EWaTT) – Constructed Wetlands

In many regions of the world clean fresh water becomes a limited resource. One option to alleviate this water scarcity is to treat wastewater by inexpensive near-nature-like methods with low energy-need in order to enable a sustainable reuse of the treated water.

Constructed wetlands bear a number of economic and ecologic advantages for the treatment of different waters, e. g. domestic and industrial waste water, acid mine drainage, etc.. However, the present knowledge about active reaction processes of constructed wetlands, i.e. the rhizosphere with its complex interactions among plants, micro-organisms, soil, and pollutants is mostly empirical.

For instance, removal processes for bacteria (hygienisation) are still not understood; besides grazing by protozoa, the elimination by bdellovibria and bacteriophages is not known. The actual pathways of nitrogen removal are largely unknown. Recent indications show that ANAMMOX processes may play an important role for N-cycling in constructed wetlands. Low attention was also paid to sulphur transformation processes; in particular the effect of the different sulphur transformation processes on the C and N cycling are unknown.

In general, our philosophy and objective is to use newly gained fundamental knowledge to optimize the biological interaction forces in the rhizosphere for the development of appropriate water treatment technologies. This approach is essential if inexpensive and simple systems are to be developed to tackle countries' environmental problems (especially in the areas of waste water, contaminated groundwater and sludge) irrespective of their industrial possibilities.

Constructed Wetlands – Treating Wastewater with Cenoses of Plants and Microorganisms CW_Booklet.pdf (1.4 MByte)