东北黑土区融雪径流侵蚀力时空分布

Spatial and Temporal Distribution of Snowmelt Runoff Erosivity in theBlack Soil Area of Northeast China

[目的]融雪侵蚀是东北黑土区主要土壤侵蚀形式之一,是该区土地退化的重要作用力,融雪径流侵蚀力是计算融雪径流侵蚀量的关键因子,因此研究融雪径流侵蚀力具有重要意义。融雪径流侵蚀力主要受积雪深度、辐射强度及升温速率影响,其主要驱动力包括融雪速率和地表径流作用。[方法]通过计算近31年日均融雪径流侵蚀力,分析东北黑土区融雪径流侵蚀力时空分布特征,并利用地理探测器辨析各区域融雪径流侵蚀力的主要影响因子。[结果]3个黑土亚区1990—2020年日均融雪径流侵蚀力均呈现先增大后减小态势,近些年逐步趋于稳定,多年日均融雪径流侵蚀力为0.01(MJ·mm)/(hm ^(2)·h·a);空间上多年日均融雪径流侵蚀力在0~0.21(MJ·mm)/(hm ^(2)·h·a)范围内,基本呈现中间小、四周大规律。融雪径流侵蚀力影响因子空间上表现为积雪深度北部大、南部小,太阳辐射强度呈现由西向东递减,升温速率值从北部向南部递减。通过地探测器辨析融雪径流侵蚀力影响因子作用强弱发现,升温速率对蒙东黑土亚区作用最强,而积雪深度对松嫩黑土亚区及三江黑土亚区作用最强。[结论]通过分析1990—2020年东北黑土区融雪径流侵蚀力时空特征及其影响因子,对于深化研究区融雪径流侵蚀特征及融雪侵蚀防控具有一定的理论和实践意义。

[Objective]Snowmelt erosion is one of the main forms of soil erosion in the black soil area of Northeast China,which plays an important role in land degradation in the area.The erosivity of snowmelt runoff is the key factor for calculating the erosion amount of snowmelt runoff,so it is of great significance to study the erosivity of snowmelt runoff.The erosivity of snowmelt runoff is mainly affected by snow depth,radiation intensity and warming rate,and its main driving forces include snowmelt rate and surface runoff.[Methods]The erosivity of daily average snowmelt runoff in the past 31 years was calculated,the temporal and spatial distribution characteristics of snowmelt runoff erosivity in the black soil area of Northeast China were analyzed,and the main influence factors of snowmelt runoff erosivity in each region were analyzed by using geographic detectors.[Results]The daily average snowmelt runoff erosivity in the three black soil subregions from 1990 to 2020 showed a trend of first increasing and then decreasing,and gradually stabilized in recent years,and the erosivity of daily average snowmelt runoff for many years was 0.01(MJ·mm)/(hm^( 2)·h·a).Spatially,the erosivity of multi-year daily average snowmelt runoff was in the range of 0~0.21(MJ·mm)/(hm ^(2)·h·a),showing a pattern of small in the middle and large in the surrounding areas.The influence factors of snowmelt runoff erosivity in spatial were as follows,the snow depth was large in the north and small in the south,the solar radiation intensity decreased from west to east,and the warming rate decreased from north to south.The influence factor of snowmelt runoff erosivity were analyzed by ground detector,and it was found that the warming rate had the strongest effect in the Mengdong black soil subregion,while the snow depth had the strongest effect in the Songnen black soil subregion and the Sanjiang black soil subregion.[Conclusion]Analyzing the spatiotemporal characteristics and influence factors of snowmelt runoff erosivity in the black soil region of Northeast China from 1990 to 2020 had certain theoretical and practical significance for deepening the study of snowmelt runoff erosivity characteristics and snowmelt erosion prevention in the study area.