Environmental impact of macrophytes on some fresh water bodies in Washim district, Maharashtrastate, India

Study of environmental impact of macrophytes on fresh water bodies in Washim district were undertaken during the year 2009 to March 2011. Ten species were observed belonging to different classes, out of which Hydrilla verticillata (L.F.) Royle, Chara spp, Potamogteon pectinatus L, Najas minor L. and  Ceratophyllum demersum L. were found to be dominating. During most of the year, surface of the water, especially in the shallow areas were found to be covered with these macrophytes. However  Hydrilla verticillata (L.F.) Royle, a rooted submerged  weed was observed to be dominant on other weeds. Other less dominant macrophytes found in the fresh water bodies were Ottelia alismoides (L.) Pers , Typha angustata Bory and Choub .,Vallisneria spiralis L. And Limnophylla sessiflora L These macrophytes were found to be responsible for reducing water  storage capacity in the fresh water bodies and also cause tremendous loss of surface water of the dam through evapotranspiration. Macrophytes also reduce pond productivity by causing accumulation of silts. Due to excessive growth after  death, the plants produce excess amount of nutrients which pollute the water and impart faul smell to the water. Therefore the rapid spread of aquatic weeds in the fresh water bodies in Washim district by vegetative and other means is creating serious socio-economic problems, causing enormous economic loss of water resources. [authors abstract]