Changes in Floral and Entomological Diversity in Subhas Sarobar Area, A Manmade Urban Lake in Kolkata, Due to Anthropogenic Stress

The present paper deals with the relative frequency, density and abundance of the floral components estimated, using the quadrat method as a course curriculum of Gurudas College, Kolkata for the last 10 years in the Subhas Sarobar area, a manmade lake in Kolkata megacity. Documentation of the angiospermic plants both aquatic and terrestrial is also carried out each year. Subhas Sarobar is a manmade urban wetland and considered to be the 'lungs' of East Kolkata. The geographical coordinates are 22° 34'7'' North latitude and 88° 24'2'' East latitude. The pressure of human activities on the Subhas Sarobar has increased manifold in recent times due to work on the Subhas Sarobar-Central Underground section of the East West Metro line by the Kolkata Metro Rail Corporation. (KMRC) going on from 2010. The quadrat studies over ten years have shown a change in the floral components, more noticeable after the commencement of the East West Metro work. Subhas Sarobar is also home to different species of insects which were documented during the survey work to this massive water body. Insects were later identified by entomologists. These insects often act as bio indicators that reflect the ecological health of the water body. Understanding the impact of anthropogenic stress on the angiospermic and entomological diversity in Subhas Sarobar the present documentation study and related conservation concern is communicated for future sustainable planning.