TITLE:
Dynamic Monitoring of Plant Cover and Soil Erosion Using Remote Sensing, Mathematical Modeling, Computer Simulation and GIS Techniques
AUTHORS:
Z. Y. Zeng, J. Z. Cao, Z. J. Gu, Z. L. Zhang, W. Zheng, Y. Q. Cao, H. Y. Peng
KEYWORDS:
Atmospheric Correction; Field Measurement; Modeling; Regression; Simulation; Soil Erosion; Vegetation Coverage; Vegetation Index
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.4 No.7,
July
17,
2013
ABSTRACT: Dynamic
monitoring of plant cover and soil erosion often uses remote sensing data,
especially for estimating the plant cover rate (vegetation coverage) by
vegetation index. However, the latter is influenced by atmospheric effects and
methods for correcting them are still imperfect and disputed. This research
supposed and practiced an indirect, fast, and operational method to conduct
atmospheric correction of images for getting comparable vegetation index values
in different times. It tries to find a variable free from atmospheric effects,
e.g., the mean vegetation coverage value of the whole study area, as a basis to
reduce atmospheric correction parameters by establishing mathematical models
and conducting simulation calculations. Using these parameters, the images can
be atmospherically corrected. And then, the vegetation index and corresponding
vegetation coverage values for all pixels, the vegetation coverage maps and
coverage grade maps for different years were calculated, i.e., the plant cover monitoring was realized. Using the vegetation
coverage grade maps and the ground slope grade map from a DEM to generate soil
erosion grade maps for different years, the soil erosion monitoring was also
realized. The results show that in the study area the vegetation coverage was
the lowest in 1976, much better in 1989, but a bit worse again in 2001. Towards
the soil erosion, it had been mitigated continuously from 1976 to 1989 and then
to 2001. It is interesting that a little decrease of vegetation coverage from
1989 to 2001 did not lead to increase of soil erosion. The reason is that the
decrease of vegetation coverage was chiefly caused by urbanization and thus
mainly occurred in very gentle terrains, where soil erosion was naturally
slight. The results clearly indicate the details of plant cover and soil
erosion change in 25 years and also offer a scientific foundation for plant
and soil conservation.