干旱区生态环境知识资源中心

Qinghai Lake, which is the largest salt water lake in China and a major obstacle in the burgeoning Eastward desertification from West China, has a vital role in the ecological sustainability of Tibetan Plateau. From the ecological perspective, the environment of Qinghai Lake became worse since the end of last century, while due to its remoteness, the field surveys in this area are difficult to carry out. Chlorophyll-a concentration in water is one of the most basic indices for water quality. In this paper, the water reflectance of Qinghai Lake was measured using ASD Fieldspec spectrometer and the water samples were collected simultaneously. The Chlorophyll-a concentration was correlated to the features of the hyperspectral reflectance, and the results showed that the first-derivative reflectance is better correlated with the water chlorophyll-a concentration.