Saxena, AmitaKuveskar, Sagar Vijay2019-04-272019-04-272019-03http://krishikosh.egranth.ac.in/handle/1/5810101199The present study was conducted to study the decadal changes occurring in Bhimtal and Naukuchiatal Lake catchment area. 4 classes were defined as Agriculture, Forest, Water and Built-up land. Maximum changes have been observed in built-up area in Bhimtal Lake and Naukuchiatal Lake catchment area. Decadal changes of water-spread area of both the Lake were studied by ENVI 4.7 software which showed that the decadal change in pre-monsoon i.e. from 2008 to 2018 was observed to be decrease in 4.05 ha whereas in post monsoon it was observed to increase by 0.72 ha in Bhimtal Lake. In Naukuchiatal Lake the decadal change in pre-monsoon i.e. from 2008 to 2018 was observed to be increase in 1.44 ha. Whereas in post monsoon it was observed to increase by 0.54 ha. Monthly physico-chemical parameter like DO, CO2, alkalinity, transparency, pH, TDS and temperature of both the Lakes were studied. Naukuchiatal Lake had better DO. Thematic map of planktonic bloom showed that highest phytoplankton distribution was found in May 2018 at 79ᵒ 33’ 25 “ E longitude and 29ᵒ 20’ 49.82 “N latitude. In Naukuchiatal Lake phytoplankton were more concentrated at 79ᵒ 35’ 1.5 “ E longitude and 29ᵒ 19’ 12.05 “N latitude in May. The highest zooplankton distribution was found in May 2018 at 79ᵒ 33’ 38 “ E longitude and 29ᵒ 20’ 26“ N latitude in Bhimtal Lake. In Naukuchiatal Lake zooplankton were more concentrated at 79ᵒ 35’ 8.5 “ E longitude and 29ᵒ 19’ 17.05 “N latitude in May. In broad sense Zooplankton were more in Bhimtal Lake and phytoplankton were more in Naukuchiatal Lake. Biodiversity of fishes and macrophyte was more in Bhimtal Lake. Among which commonly occurred species in both lakes were Tor tor, Nemachilus montanus, Tor putitora, Barilius bendelisis, Schizothorax progastus, Chanda spp, Cirrhinus mrigala, Cyprinus carpio.ennullThesis