摘要
黄土高原的脆弱生态环境导致降雨侵蚀现象频发,准确评估降雨侵蚀力对优化该区生态管理策略具有重要意义。然而,不同降雨侵蚀力估测模型差异导致其时空演变规律及驱动机制差异。因此,利用黄土高原1990—2021年小时降雨数据,分析雨量与雨强模型计算的降雨侵蚀力差异,揭示不同季节、雨型、海拔等特征参量对两模型降雨侵蚀力时空分布规律的影响。结果显示:(1)黄土高原基于雨强计算的年均降雨侵蚀力均值为918.36MJ mm hm^(-2) h^(-1),范围在222.81—2583.52MJ mm hm^(-2) h^(-1);基于雨量计算的年均降雨侵蚀力均值为1058.17MJ mm hm^(-2) h^(-1),范围在271.92—2700.71MJ mm hm^(-2) h^(-1)。(2)两种模型计算出的降雨侵蚀力空间分布和时间变化相似,但基于雨强计算得到的降雨侵蚀力变异系数更高,变异系数为0.44。(3)不同雨型、季节的降雨侵蚀力值空间分布相似,随季节推移,夏季降雨侵蚀力值最高且分布最广;且雨强模型对海拔更敏感,相关系数为-0.58。综上,综合考虑雨量与雨强的双重效应可有效反映黄土高原降雨侵蚀过程的动态特征,准确评估降雨侵蚀力对区域特征参量变化的响应,有助于黄土高原生态环境的保护、支撑政府间水土保持相关策略的制定。
The fragile ecological environment of the Loess Plateau significantly increases the susceptibility to rainfall erosion,underscoring the importance of accurately assessing rainfall erosivity to optimize ecological management strategies in this region.However,discrepancies in rainfall erosivity estimation models have led to variations in spatiotemporal patterns and driving mechanisms,complicating the understanding of erosion dynamics.To address this,this study utilized high⁃resolution hourly rainfall data from 281 stations across the Loess Plateau spanning the period from 1990 to 2021.The research aimed to analyze the differences between rainfall erosivity models based on rainfall amount and rainfall intensity,and to explore the spatiotemporal distribution patterns of rainfall erosivity derived from these models.Furthermore,the study investigated the influence of key factors such as seasonal variations,rainfall types,and elevation on the formation and distribution of rainfall erosivity.The results revealed several critical findings:(1)The annual average rainfall erosivity calculated using the rainfall intensity model was 918.36MJ mm hm^(-2) h^(-1),with values ranging from 222.81 to 2583.52MJ mm hm^(-2) h^(-1).In contrast,the annual average rainfall erosivity derived from the rainfall amount model was 1058.17MJ mm hm^(-2) h^(-1),with a range of 271.92 to 2700.71MJ mm hm^(-2) h^(-1).(2)While both models yielded comparable spatial and temporal patterns in rainfall erosivity,the model predicated on rainfall intensity exhibited a greater degree of variability,as evidenced by its higher coefficient of variation(CV)of 0.44.This elevated CV underscores the heightened sensitivity of the rainfall intensity model to interannual fluctuations and variations in the characteristics of rainfall events,suggesting that it is more responsive to changes in rainfall patterns over time.(3)The spatial patterns of rainfall erosivity were consistent across different rainfall types and seasons,with the highest values and most extensive distribution observed during the summer months.Additionally,the rainfall intensity model demonstrated greater sensitivity to elevation,as evidenced by a correlation coefficient of-0.58,suggesting that elevation plays a significant role in influencing rainfall erosivity when calculated using this model.In conclusion,this study highlights the importance of integrating the dual effects of rainfall amount and intensity to accurately capture the dynamic characteristics of rainfall erosion processes on the Loess Plateau.By providing a more precise evaluation of rainfall erosivity and its response to regional parameter variations,this research supports efforts to conserve the fragile ecological environment of the Loess Plateau.Furthermore,the findings offer valuable insights for policymakers in formulating effective soil and water conservation strategies,ultimately contributing to sustainable land management and ecological restoration in the region.
作者
谢乐
侯鹏
周涛
刘亦晟
王家豪
任晓琦
XIE Le;HOU Peng;ZHOU Tao;LIU Yisheng;WANG Jiahao;REN Xiaoqi(Chinese Research Academy of Environmental Sciences,Beijing 100012,China;Satellite Environment Application Center,Ministry of Ecology and Environment,Beijing 100094,China;Central South University of Forestry and Technology,Changsha 410004,China;School of Geomatics and Urban Spatial Informatics,Beijing University of Civil Engineering and Architecture,Beijing 100044,China;College of Geodesy and Geomatics,Shandong University of Science and Technology,Qingdao 266590,China)
出处
《生态学报》
北大核心
2025年第10期4940-4951,共12页
Acta Ecologica Sinica
基金
国家重点研发计划项目(2024YFF1306105)。
关键词
降雨侵蚀力
高时间分辨率
模型差异
时空变化
rainfall erosivity
high temporal resolution
differences of models
spatiotemporal patterns
