石漠化喀斯特皆伐迹地的土壤侵蚀特征  

Soil erosion characteristics of clear cutting plots in Karst rocky desertification area

作　　者：石燕金 周运超[1,2] SHI Yanjin;ZHOU Yunchao(Forest Resources and Environment Research Center of Guizhou Province,School of Forestry,Guizhou University 550025,Guiyang,China;Puding Karst Ecosystem Research Station,Chinese Academy of Sciences 562100,Puding,Guizhou,China)

机构地区：[1]贵州省森林资源与环境研究中心贵州大学林学院,贵阳550025 [2]中国科学院普定喀斯特生态系统观测研究站,贵州普定562100

出　　处：《中国水土保持科学》2018年第5期114-119,共6页Science of Soil and Water Conservation

基　　金：国家重大科学研究计划"基于水-岩-土-气-生相互作用的喀斯特地区碳循环模式及调控机理"(2013CB956702);贵州省一流学科建设项目(GNYL[2017]007);贵州百层次人才创新项目(QHKRC-2015-4022);黔科合基金[2017]1018

摘　　要：为研究石漠化喀斯特皆伐迹地自然恢复过程中土壤侵蚀的量、变化规律和发生机理,在贵州省普定县设置喀斯特石漠化皆伐样地,采用测钎法(均匀布点)径流场法2种方法,对该样地恢复过程中土壤侵蚀进行持续的监测,对比2种监测方法的结果及以确定其适用性。结果显示:在皆伐后的4年半恢复过程中,测钎法结果显示总体呈侵蚀趋势,累积侵蚀深度达1. 46 cm(折合侵蚀模数为2 066. 7 t/(km2·a));自然恢复1年内土壤侵蚀量波动较大,在1年之后则波动减小(除2015年4月(约恢复3年)),3. 5年后趋于稳定;径流场法得出的侵蚀模数为0. 78 t/(km2·a),与测钎法得出的土壤侵蚀结果相差巨大,分析认为这可能是由喀斯特特殊的地表岩土结构和2种监测方法具有不同的观测侧重点及性质共同造成的,2种方法观测结果不具有普遍的可比性(如喀斯特特殊地表、地下状况等不可比),测钎法由于能通过原位监测土壤蠕滑及地下漏失而更适用于该地区。此研究对喀斯特石漠化皆伐迹地的土壤侵蚀量和变化规律有一些认识,但是对于其影响因素还只限于推测,有待开展进一步的研究确认。[Background]As a result of low content of acid insoluble material in bedrock and the slow weathering rate of rock in Karst area,the rate of soil formation is very little,and extremely serious environmental and social problems will occur while soil is eroded. Moreover,it is difficult to monitor soil erosion accurately because of the complex structures above ground and underground at Karst area. Here we are trying to find appropriate method to monitor the amount, variation pattern, and formation mechanism of soil erosion during the natural restoration of a typical clear cutting in Karst area in Puding county of Guizhou province. [Methods] Drilling method is appropriate to trace soil erosion in situ according to previous studies,it was combined with runoff plot method to be used in this study. Test bras had been set by uniform distribution of a interval of 1 meter and the distance from top of bras to soil surface was measured each time to obtain the erosion depth between ever two measurement. on the otherhand,runoff plot was built around the clear cutting plot and sediment was collected and weighed after every heavy rainfall. The result of these two methods was compared. [Results]1） During the 4. 5 years of restoration after clear cutting,the result by drilling method showed an overall trend of erosion,with a cumulative erosion depth of 1. 46 cm（ Equivalent erosion modulus 2 066. 7 t/（ km2·a））,which had a large fluctuation at the first one year of the natural recovery,then the fluctuation,decreased（ except the test of April 2015（ about 3 years of the natural recovery））,and tended to be stable after 3. 5 years. 2）The erosion modulus obtained by the runoff plot method was 0. 78 t/（ km2·a）,and the sediment can only be collected after one rainfall of 67. 6 mm,which rainfall intensity reached 42. 4 mm/h within two months after clear cutting. 3） There was a huge difference between the erosion modulus obtained from the drilling method and runoff plot method（ about 2 065. 92 t/（ km2·a））.

关 键 词：喀斯特石漠化 皆伐 土壤侵蚀 测钎法 径流场 贵州 

分 类 号：S157.1[农业科学—土壤学]