Artificial wetlands, an opportunity for conservation of biodiversity (Case study: wastewater treatment plant of Yazd city)

Waste water treatment plant of Yazd city was established in early 1990s and now about 30% of household waste water of city is treated in aerobic and anaerobic lagoons and released to an area of 200 ha with 180 ha green space. Thus an artificial wetland has been created in the region with no previous plant cover. In this study the environmental aspects of this artificial wetland were investigated in the region of arid and desert in Yazd province. Fifteen waterfowl and migratory as well as terrestrial birds were identified in the study area during four years of monitoring in winter (January). The most important migratory bird species that observed during this study were Anas crecca, Anas platyrhynchos, Himantopus himantopus and Phoenicopterus ruber and most important of land birds were Falco cherrug, Falco tinnunculus, Aquila rapax and Motacilla alba. Reed and some of planted trees such as Tamarix, Halloxyllon and Eucalyptus were the most important plants of the wetland. The results showed that this artificial wetland had positive effects in terms of creating a suitable place for temporary settlement of passing and wintering migratory birds, developing green space in the country side and air quality improvement. But it would have the negative side effects such as probabilities of microbial pollution propagation through the bird populations, the appearance of various insects, probability of new diseases incidence in the region and soil contamination.