Human activities have been a key driver of hydraulic erosion changes in
northeastern China over the past 37 years
Abstract
Northeast China is experiencing severe soil erosion, resulting in land
degradation and nutrient loss. Among them, hydraulic erosion poses the
greatest threat to food security. Combining various multi-source data,
we applied the modified soil erosion equation (RUSLE) to evaluate
hydraulic erosion modulus in Northeast China’s black soil
region(1985–2021). We used the threshold segmentation and residual
analysis method to quantify the relative roles of climate change and
human activities on hydraulic erosion. The outcomes were presented
below: (1) The yearly mean hydraulic erosion modulus was 804.78 t·km
-2·a -1 and decreases significantly
with a slope of -11.114 t·km -2·a
-1. The area with significant growth in erosion
modulus covered 23.77% of the overall area and was mainly spread in
grassland and farmland. The areas with a significant decrease in erosion
modulus covered 19.82% and were mainly spread in natural forests. (2)
In areas with significant increases in erosion, 20.39% of the total
area was attributed to anthropogenic factors and 3.38% of the total
area was attributed to natural factors. In areas where soil erosion was
significantly reduced, 17.67% and 2.15% were attributed to ecological
restoration and natural factors, respectively. (3) Deforestation,
grassland degradation, and unreasonable farming still exist. The area of
sloping cropland (≥6°) increased by 133.9 km 2 per
year, and sloping land erosion increased by 0.187 · 10 10 t per year.
The focus of soil erosion prevention and control in northeast China is
ecological restoration of grasslands, sloping land management, and
conservation tillage.