水保所知识产出(1956---)知识库

Changwu County is a typical soil and water loss area on the Loess Plateau. Soil erosion
is an important ecological process, and the impact of land use/cover change on soil erosion has
received much attention. The present study used remote sensing images of the study area in 1987,
1997, 2007, and 2017 to analyze the land use/cover change (LULCC), and the RUSLE model was
applied to estimate the soil erosion in different times. We exploited the Sankey diagram to visualize
the spatiotemporal changes in land use/cover and soil erosion. We planned to obtain the most
suitable model by comparing the application of different spatial regression models (Geographically
weighted regression model, Spatial lag model, Spatial error model) and Ordinary least squares in
LULCC and soil erosion changes. The results revealed that land use/cover has significantly changed
in the last 30 years. From 1987 to 1997, cropland expansion came mainly from planted land and
orchards, which transformed 68.99 km 2 and 64.93 km 2 , respectively. In 1997–2007, the planted land
increase was mainly through the conversion of cropland. In 2007–2017, the increase in orchard area
came mainly from cropland. The forest land increase was mainly from the planted land. Soil erosion
in Changwu County was dominated by slight erosion and light erosion, although the area of slight
erosion and light erosion continued to decrease. The annual average soil erosion increased, which
was estimated at 977.84 ton km − 2 year − 1 , 1305.17 ton km − 2 year − 1 , 1310.60 ton km − 2 year − 1 , and
1891.46 ton km − 2 year − 1 in 1987, 1997, 2007, and 2017, respectively. These amounts of transformation
mainly occurred when slight erosion was converted to light erosion, light erosion was converted to
moderate erosion, and moderate erosion was converted to light and severe erosion. The Spatial lag
model and Spatial error model have higher accuracy than the Geographically weighted regression
model and Ordinary least squares when fitting the effect of LULCC and soil erosion change, where
the accuracy exceeded 0.62 in different periods.