Influences of sand cover on erosion processes of loess slopes based on rainfall simulation experimen

来源 :干旱区科学 | 被引量 : 0次 | 上传用户:jin_liu
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
Aeolian-fluvial interplay erosion regions are subject to intense soil erosion and are of particular conc in loess areas of northwest China.Understanding the composition,distribution,and transport processes of eroded sediments in these regions is of considerable scientific significance for controlling soil erosion.In this study,based on laboratory rainfall simulation experiments,we analyzed rainfall-induced erosion processes on sand-covered loess slopes (SS) with different sand cover patts (including length and thickness) and uncovered loess slopes (LS) to investigate the influences of sand cover on erosion processes of loess slopes in case regions of aeolian-fluvial erosion.The grain-size curves of eroded sediments were fitted using the Weibull function.Compositions of eroded sediments under different sand cover patts and rainfall intensities were analyzed to explore sediment transport modes of SS.The influences of sand cover amount and patt on erosion processes of loess slopes were also discussed.The results show that sand cover on loess slopes influences the proportion of loess erosion and that the compositions of eroded sediments vary between SS and LS.Sand cover on loess slopes transforms silt erosion into sand erosion by reducing splash erosion and changing the rainfall-induced erosion processes.The percentage of eroded sand from SS in the early stage of runoff and sediment generation is always higher than that in the late stage.Sand cover on loess slopes aggravates loess erosion,not only by adding sand as additional eroded sediments but also by increasing the amount of eroded loess,compared with the loess slopes without sand cover.The influence of sand cover patt on runoff yield and the amount of eroded sediments is larger than that of sand cover amount.Furthermore,given the same sand cover patt,a thicker sand cover could increase sand erosion while a thinner sand cover could aggravate loess erosion.This difference explains the existence of intense erosion on slopes that are thinly covered with sand in regions where aeolian erosion and fluvial erosion interact.
其他文献
Fagonia cretica L.is an important component of Mediterranean dry grasslands and a rare and isolated species of Italian flora.In this study,an assessment is pres
Hydrological models are often linked with other models in cognate sciences to understand the interactions among climate,earth,water,ecosystem,and human society.
Climate change and human activities can influence vegetation net primary productivity (NPP),a key component of natural ecosystems.The Qinghai-Tibet Plateau of C
Reconstructing the hydrological change based on dendrohydrological data has important implications for understanding the dynamic distribution and evolution patt
In developing countries such as Ethiopia,research to develop and promote soil and water conservation practices rarely addressed regional diversity.Using a water
In recent year,desertification has become one of the most important environmental hazards all over the world,especially in developing countries such as Iran.Und
The complex interactions in desert ecosystems between functional types and environmental conditions could be reflected by plant water use patts.However,the mech
Most ecological studies in North Africa reveal a process of continuous degradation of rangeland ecosystems as a result of overgrazing.This degradation appears a
Desert mosses,which are important stabilizers in desert ecosystems,are distributed patchily under and between shrubs.Mosses differ from vascular plants in the w
The community assembly rules and species coexistence have always been interested by ecologists.The community phylogenetic structure is the consequence of the in