|
|
|
| Analysing developing trend of chlorophyll-a concentration in Chaohu Lake based on TM/ETM+ image |
|
|
|
|
Abstract 6 periods remote sensing data from 1995~2007 of Chaohu area were processed. The method of many dark pixels was adopted to carry out atmospheric modification and the modified normalized difference water index (MNDWI) was adopted to get the information of water. On this basis, the information of chlorophyll-a relative concentration in Chaohu Lake was extracted by the model of (TM2+TM4-TM3)/ln[TM3]. The area of high concentration was mainly distributed in the western of Chaohu Lake; The water quality of Nanfei River contributed more to algae bloom in Chaohu Lake; The area of high concentration increased by 1.82-fold from 1995 to 2006 and had tendency of expanding to the east of Chaohu Lake, with the degree of eutrophication still aggravating.
|
|
Received: 19 September 2009
|
|
|
|
|
|
|
