荒漠化草原植被斑块分布对地表径流、侵蚀及养分流失的影响

摘要/Abstract

摘要： 地表径流是干旱区水、养分和土壤物质迁移和再分配的主要途径之一,它在很大程度上受植被格局的影响。研究了腾格里沙漠东南缘生物土壤结皮斑块和灌丛斑块镶嵌分布的植被格局对地表径流、侵蚀及其驱动下的资源再分配的影响。结果表明,植被斑块对地表径流和侵蚀产物起着拦截作用,能显著减少资源的流失。生物土壤结皮斑块和植被斑块之间存在资源(径流、侵蚀产物及养分等)再分配的源-汇关系。模拟降雨条件下,含有灌丛斑块和生物土壤结皮斑块的样方出现表面积水和径流需要的时间均显著大于只含生物土壤结皮斑块的样方;含两类斑块的样方出现径流需要的降雨量显著大于只含生物土壤结皮斑块的样方。在模拟降水和自然降水条件下,生物土壤结皮斑块产生的径流、侵蚀产物、有机质、氮及溶解养分中均大量被位于下坡向的灌丛斑块截获;灌丛斑块土壤水分入渗深度显著大于结皮斑块。灌丛斑块对生物土壤结皮斑块产生的地表径流、侵蚀产物及其携带的资源的捕获能显著减少资源流失,有效地防止荒漠化的进一步发生发展。

关键词: 地表径流, 资源再分配, 斑块植被, 源-汇关系, 荒漠化草原, 腾格里沙漠

Abstract: Runoff is the dominant pathway of water, nutrients and soil materials transfer and redistribution in arid land, which is strongly affected by vegetation pattern. The influences of the mosaic distribution of biological soil crust patches and spot-structured shrub patches in desertified steppe area in southeast fringe of Tengger desert on runoff, soil erosion, sedimentation and related resources redistribution were investigated. The results show that vegetation patches could obstruct the runoff and sediment, which inevitably leads to the reduction of resources losses. There is a source-sink relationship for resource (water, sediments and nutrients) redistribution between the biological soil crust patch and shrub patch. Under the simulated rainfall condition, the time of ponding and runoff commencement in the plots consisting of both crust and shrub patches is significantly longer than those in the plot consisting of only crust patches; the volume of rainfall for runoff commencement of the former was remarkably greater than that of the latter. In simulated and natural rainfall events, the shrub patches effectively obstructed and captured the runoff and carried sediments, organic matter and nitrogen, etc, which are generated from the biological soil crust patch. The water penetration depth in shrub patches was significantly greater than that in crust patches. The resource capture of shrub patches effectively decreases resource leakage, which is beneficial to desertification prevention.

Key words: runoff, resource redistribution, patchy vegetation, source-sink relationship, desertified steppe, Tengger desert

中图分类号:

P334.2

李小军;汪君;高永平. 荒漠化草原植被斑块分布对地表径流、侵蚀及养分流失的影响[J]. 中国沙漠, 2011, 31(5): 1112-1118.

LI Xiao-jun;WANG Jun;GAO Yong-ping. Effects of Vegetation Patchy Distribution on Runoff, Erosion and Nutrients Loss in Desertified Steppe Area[J]. JOURNAL OF DESERT RESEARCH, 2011, 31(5): 1112-1118.

参考文献

[1]Shachak M,Sachs M,Moshe I.Ecosystem management of desertified shrublands in Israel[J].Ecosystems,1998,1:475-483.
[2]Mabbutt J A,Fanning P C.Vegetation banding in arid western Australia[J].Journal of Arid Environments,1987,12:41-59.
[3]Tongway D J,Ludwig J A.Small scale resource heterogeneity in semiarid landscapes[J].Pacific Conservation Biology,1994,1:201-208.
[4]Schlesinger W H,Reynolds J F,Cunningham G L,et al.Biological feedbacks in global desertification[J].Science,1990,247:1043-1048.
[5]Puigdef Bregas J,Sanchez G.Geomorphological implications of vegetation patchiness on semi-arid slopes[M]//Anderson M G,Brooks S M.Advances in Hillslope processes.Vol.2.Wiley,Chichester,UK,1996:1027-1060.
[6]Eldridge D J,Greene R S B.Microbiotic soil crusts:a review of their role in soil and ecological processes in the rangelands of Australia[J].Australian Journal of Soil Research,1994,32(3):389-415.
[7]潘颜霞,王新平.荒漠人工植被区浅层土壤水分空间变化特征研究[J].中国沙漠,2007,27(2):250-256.
[8]Rostagno C M.Infiltration and sediment production as affected by soil surface condition in a shrubland of Patagonia,Argentina[J].Journal of Range Management,1989,42:382-385.
[9]Cammeraat L H,Imeson A C.The evolution and significance of soil vegetation patterns following land abandonment and fire in Spain[J].Catena,1999,37:107-127.
[10]Bergkamp G,Cerda A,Imeson A C.Magnitude-frequency analysis of water redistribution along a climate gradient in Spain[J].Catena,1999,37:129-146.
[11]Puigdefabregas J,Sole A,Gutierrez L,et al.Scales and processes of water and sediment redistribution in drylands:results from the Rambla Honda field site in Southeast Spain[J].Earth-Science Reviews,1999,48:39-70.
[12]Noy-Meir I.Desert ecosystems:environment and producers[J].Annual Review of Ecology and Systematics,1973,4:25-51.
[13]李小军,谭会娟,张志山,等.油蒿不同部位水分关系研究[J].中国沙漠,2007,27(3):448-454.
[14]Wilcox B P,Breshears D D,Allen C D.Ecohydrology of a resource-conserving semi-arid woodland:effects of scale and disturbance[J].Ecological Monograph,2003,73(2):223-239.
[15]黄满湘,章申,晏维金.农田暴雨径流侵蚀泥沙对氮磷的富集机理[J].土壤学报,2003,42(2):306-310.
[16]郑粉莉,白红英,安韶山.草被地上和地下部分拦蓄径流和减少泥沙的效益分析[J].水土保持研究,2005,12(5):86-88.
[17]汪有科.森林植被水土保持功能评价[J].水土保持研究,1994,1(3):24-30.
[18]Barger N N,Herrick J E,Zee J V,et al.Impacts of biological soil crust disturbance and composition on C and N loss from water erosion[J].Biogeochemistry,2006,77:247-263.
[19]王新平,肖洪浪,张景光,等.荒漠地区生物土壤结皮的水文物理特征分析[J].水科学进展,2006,17(5):592-598.
[20]Ludwig J A,Wilcox B P,Breshears D D,et al.Vegetation patches and runoff-erosion as interacting ecohydrological processes in semi-arid landscape [J].Ecology,2005,86(2):288-297.
[21]Deuchras S A,Townend J,Aitkenhead M J,et al.Changes in soil structure and hydraulic properties in regenerating rain forest[J].Soil Use and Management,1999,15:183-187.
[22]冯丽,张景光,张志山,等.沙坡头人工固沙区油蒿繁殖分配的研究[J].中国沙漠,2008,28(3):473-477.
[23]李新荣,张志山,王新平,等.干旱区土壤-植被系统恢复的生态水文学研究进展[J].中国沙漠,2009,29(5):845-852.
[24]张志山,樊恒文,赵金龙,等.沙漠人工植物群落的根系分布及动态[J].中国沙漠,2006,26(4):637-643.
[25]Yair A,Lavee H.Runoff generation in arid and semi-arid zones[M]//Anderson M G,Burt T P.Hydrological Forecasting.Wiley,Chichester,UK ,1985:183-220.
[26]Boer M,Puigdefábregas J.Effects of spatially structured vegetation patterns on hillslope erosion in a semiarid Mediterranean environment:a simulation study[J].Earth Surface Processes and Landform,2005,30:149-167.
[27]Itzhak K,Blumberg D G,Lavee H,et al.Spatial distribution dynamics of topsoil moisture in shrub microenvironment after rain events in arid and semi-arid areas by means of high resolution maps[J].Geomorphology,2007,86:455-464.