Comparison of calculation methods of ecological evaluation indexes

The remote sensing evaluation index can quickly monitor and evaluate regional ecological quality. A more convenient method which can also bring accurate results in practical application is still under discussion. Based on Landsat 8 OLI and Sentinel-2, taking Dianchi Lake Reserve in Kunming as an example, the changes of ecological environment quality in Dianchi Lake Reserve are obtained by using the improved remote sensing ecological index analysis method (MRSEI), improved fuzzy analytic hierarchy process (FAHP), and tasseled cap transformation analysis method (K-T). The first is to establish an MRSEI model based on principal component analysis; the second is to determine the weight of each evaluation index and monitor and quantitatively evaluate the ecological environment; and the third is to carry out orthogonal transformation through the information distribution structure of soil, vegetation, and humidity in multi-dimensional spectral space, and study the applicability of K-T to Sentinel-2. The findings show that the results calculated by the three methods are generally consistent, but the FAHP is the most efficient and simple method to calculate the ecological environment quality. The MRSEI avoids the weight setting that varies from person to person. Compared with other algorithms, FAHP is simpler and has fixed coefficients, and the calculation results are relatively stable. Based on the information distribution structure of soil, vegetation, and other information in multi-dimensional spectral space in multispectral remote sensing, K-T can better highlight the characteristics of main features, reduce vegetation, weaken the information on greenness image, and enhance soil information. Taking Landsat 8 as a reference, it is found that K-T is also applicable in Sentinel-2. This paper provides a scientific basis for the construction of ecological civilization city for Dianchi Lake Reserve.