Abinash John Peter (91717001)  <br/><br/>
Spatio-temporal assessment of floating vegetation in vembanad lake using multispectral remote sensing 

 - MPhil EI 2017-2018 
<br/><br/> A study on the spatio-temporal variations of floating vegetation in Vembanad<br/>Lake during the period 2000-2016 has been done using multispectral remote<br/>sensing. The study has used medium resolution Landsat-5 TM, Landsat-7<br/>ETM, ASTER and Landsat-8 OLI-TIRS imageries of the study area. Using<br/>satellite remote sensing for the analysis present us with the advantage that<br/>it is possible to readily identify and analyse the changes occurring to the<br/>study area. Floating vegetation and cyanobacterial blooms pose threats to<br/>the ecosystem as well as to human activities, so it is important to map and<br/>monitor the growth and spread patterns. Also the cyanobacterial blooms are<br/>an indicator of water quality of the lake. By studying about the cyanobacterial<br/>blooms we get information regarding the health of the ecosystem as<br/>well.The study also analysed the spatial changes occurred to the lake, mainly<br/>the land reclamations happened during the period of study.<br/>Change detection analysis was conducted between the images of 2000 and<br/>2016 and it could be seen that there is a shrinkage of 2.678 sq.km. during<br/>the period of the study. Major land reclamations are at or around<br/>Kochi, mainly for development purposes. Different indices were calculated<br/>and NDWI showed more promise in extracting out the desired features from<br/>other land cover classes. On unsupervised classification of the NDWI profiles,<br/>a decreasing trend in the NDWI value was identified south to the Thanneermukkom<br/>barrage whereas in the northern regions of the lake, the NDWI<br/>values was more or less stable. The floating vegetation (macrophytes) map<br/>were prepared from the NDWI images and the spatial as well as temporal<br/>variation in their distribution were studied. The area of the floating vegetation<br/>varies between around 5.95 sq.km and 1.8 sq.km during the period<br/>of study, and the area is on a decreasing trend from 2008 onwards. The<br/>macrophytes are more concentrated on the southern arm of the lake than the<br/>northern stretch. 
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<br/><br/><label>Subjects--Topical Terms: </label><br/>FLOATING VEGETATION <br/>MULTISPECTRAL REMOTE SENSING<br/>VEMBANAD LAKE