中国东北松嫩平原20世纪耕地重建及时空格局变化(英文)

来源 :Journal of Geographical Sciences | 被引量 : 0次 | 上传用户:jtk
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We initially estimated the cropland area at county level using local historical documents for the Songnen Plain(SNP)in the 1910s and 1930s.We then allocated this cropland area to grid cells with a size of 1 km×1 km,using a range of cultivation possibilities from high to low;this was based on topography and minimum distances to rivers,settlements,and traffic lines.Cropland areas for the 1950s were obtained from the Land Use Map of Northeast China,and map vectorization was performed with Arc GIS technology.Cropland areas for the1970s,1980s,1990s,2000s,and 2010s were retrieved from Landsat images.We found that the cropland areas were 4.92×104 km~2 and 7.60×10~4 km~2,accounting for 22.8%and 35.2% of the total area of the SNP in the 1910s and 1930s,respectively,which increased to 13.14×10~4 km~2,accounting for 60.9%in the 2010s.The cropland increased at a rate of 1.18×10~4km~2 per decade from the 1910s to 1970s while it was merely 0.285×10~4 km~2 per decade from the 1970s to 2010s.From the 1910s to 1930s,new cultivation mainly occurred in the central SNP while,from the 1930s to 1970s,it was mainly over the western and northern parts.This spatially explicit reconstruction could be offered as primary data for studying the effects of changes in human-induced land cover based on climate change over the last century. We initially estimated the cropland area at county level using local historical documents for the Songnen Plain (SNP) in the 1910s and 1930s.We then allocated this cropland area to grid cells with a size of 1 km × 1 km, using a range of cultivation possibilities from high to low; this was based on topography and minimum distances to rivers, settlements, and traffic lines. Cropland for the 1950s were obtained from the Land Use Map of Northeast China, and map vectorization was performed with Arc GIS technology. Cropland areas for the1970s, 1980s, 1990s, 2000s, and 2010s were retrieved from Landsat images. We found that the cropland areas were 4.92 × 104 km ~ 2 and 7.60 × 10 ~ 4 km ~ 2, accounting for 22.8% and 35.2% of the total area of ​​the SNP in the 1910s and 1930s, respectively, which increased to 13.14 × 10 ~ 4km ~ 2, accounting for 60.9% in the 2010s.The cropland increased at a rate of 1.18 × 10 ~ 4km ~ 2 per decade from the 1910s to 1970s while it was merely 0.285 × 10 ~ 4 km ~ 2 per decade from the 1970s to 2010s.Fro m the 1910s to 1930s, the information is available in the central SNP while, from the 1930s to 1970s, it was mainly over the western and northern parts. This spatially explicit reconstruction could be be provided as primary data for studying the effects of changes in human -induced land cover based on climate change over the last century.
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