子午岭地区坡面浅沟侵蚀临界模型研究

Predicting Ephemeral Gully Erosion on Hillslopes of Ziwuling Area

利用子午岭地区梁坡高精度的GPS(Trimble 5700)实测数据对国内外已有的浅沟侵蚀临界模型进行了验证。结果表明,已有浅沟侵蚀临界模型模拟的子午岭地区浅沟侵蚀分布面积或大于实际浅沟侵蚀区的10%～40%,或小于实际的20%～35%。基于子午岭地区实测的梁坡GPS数据建立高分辩率的DEM,构建了适用于子午岭地区的浅沟侵蚀临界模型。利用实测GPS数据对所建浅沟侵蚀临界模型进行验证,发现用新建的浅沟侵蚀临界模型模拟的研究区梁坡浅沟侵蚀分布区与野外实际浅沟侵蚀分布区非常吻合,其误差仅为5%。

Based on high-precision GPS（Trimble 5700） measurement data on hillslopes of Ziwuling area,this paper validated the existing models for predicting ephemeral gully erosion thresholds.The results show that the existing models were 10%～40% over-predicting or 20%～35% under-predicting of the distribution area of ephemeral gully erosion on hillslopes.A new critical model for predicting ephemeral gully erosion on hillslopes was then established through the high-solution DEM generated by GPS,GIS and statistical analysis.The GPS measurement data on hillslopes of the Ziwuling area were then used to validate the newly established critical model.The results show that the new model well predicted the distribution area of ephemeral gully erosion on hillslopes with a low relative error of 5%.