区域土壤侵蚀模型PESERA介绍及其应用现状

Principles and applications of a coarse-scale soil erosion model PESERA

土壤侵蚀模型已被广泛用于认知土壤侵蚀因素、土壤侵蚀过程及其交互作用,并且成为土壤侵蚀学科研究的重点之一。多数现有土壤侵蚀模型是基于次暴雨的坡面、小流域侵蚀产沙模型,能够适用于区域尺度、长时段的土壤侵蚀模型仍较为缺乏。在我国,土壤侵蚀严重且时空分异显著,对区域尺度、长时段土壤侵蚀模型的需求尤为紧迫。PESERA模型是一个新开发的具有物理基础、大尺度、长时段、分布式土壤侵蚀模型,能够有效弥补当前土壤侵蚀模型的尺度不足,为土壤侵蚀防治和生态恢复提供科学依据。该模型充分考虑水文,土壤侵蚀与植被生长过程及其交互,具有良好的物理基础,并且已在欧洲地区进行广泛应用和验证。系统介绍了PESERA模型的原理、输入参数与输出结果及其应用、验证和改进,以期为该模型未来在国内土壤侵蚀研究中的应用提供参考。

Soil erosion models have been widely applied to predict soil erosion rates and understand interac- tions between different environmental drivers of soil erosion processes. Most of the contemporary models were developed for storm event and hills!ope or small catchment scales, and few models are capable of simulating soil erosion processes over long-term temporal scales and regional scales. This is particularly relevant for Chi- na,where soil erosion can be severe and where there are strong spatiotemporal differences,leading to an urgent need for long-term, large scale soil erosion models. Established with reference to existing soil erosion models, PESERA is a physically-based, spatially distributed,long-term, coarse scale soil erosion model. It is a useful tool for soil and water conservation and informing ecological restoration. The PESERA model explicitly de- scribes the processes of hydrology,vegetation growth, erosion and their interactions, and therefore has a robust theoretical basis. It has been widely applied and validated across Europe and is currently used by planners and policy makers to determine funding decisions for soil erosion protection measures on farms. This paper intro- duces the principles, inputs and outputs of the PESERA model, and its previous applications, validation and modifications providing a useful reference to the future applications of the model in China.