摘要
对流域径流的变化及其原因的研究,是森林水文研究领域中一个重要的科学问题.本研究以降水充沛的彭冲涧小流域为对象,运用Mann-Kendall检验法对彭冲涧小流域1983—2014年的降水、径流序列进行突变分析;采用经验统计分析法,分析降水变化和植被恢复对小流域径流的影响及其贡献率,并计算年尺度上植被恢复的水文效应对降水量响应的临界值.结果表明:2003年为降水与径流的一致突变点;相对于基准期(1983—2003年),变化期(2004—2014年)的年降水量、年径流深分别减少8.7%、29.2%,年平均减少幅度分别为12.7、22.1 mm;春、夏、秋、冬季及年尺度上的平均径流深分别减少100. 2、105. 8、25. 2、23. 4和243.0 mm,其中,降水变化的贡献率分别为58.9%、71.6%、65.5%、35.0%和57.1%,植被恢复的贡献率分别为41.1%、28.4%、34.5%、65.0%和42.9%;植被恢复的水文效应依赖于年降水量,且临界值为1181 mm.当年降水量小于1181 mm时,植被恢复增加了年径流深;当年降水量大于1181 mm时,植被恢复减小了年径流深.此临界值的存在,将有助于解释不同流域植被恢复对径流影响贡献率的差异性,有助于找到森林对径流影响存在争论和分歧的原因.
To examine the change of runoff and its reason is an important scientific issue in forest hydrology. In this study,we performed the trend and inflection analysis on the time series of daily precipitation and runoff in the Pengchongjian small watershed from 1983 to 2014 by Mann-Kendall test method,a site with abundant precipitation. Using the empirical statistics method,we analyzed the effects of precipitation variation and vegetation restoration on the runoff and its contribution rates. Furthermore,we calculated the critical value of the hydrological effect of vegetation restoration on the annual precipitation. The results showed that the year 2003 was a consistent abrupt point for annual precipitation and runoff. Compared to the baseline period(1983-2003),annual precipitation and the depth of runoff in the changing period(2004-2014) decreased by 8.7% and 29.2%,with the averaged annual decrease of 12.7 and 22.1 mm,respectively. The averaged depth of runoff in spring,summer,autumn,winter,and in the whole year decreased by 100. 2,105. 8,25. 2,23.4,and 243.0 mm,respectively. The contribution rates of the depth of runoff to precipitation variation were 58.9%,71.6%,65.5%,35.0%,and 57.1%,respectively,while the contribution rates of vegetation restoration were 41. 1%,28. 4%,34. 5%,65. 0%,and 42. 9%,respectively. The hydrological effect of vegetation restoration was attributed to the annual precipitation,with a critical value of 1181 mm. Vegetation restoration increased annual depth of runoff when annual precipitation was less than the critical value,and increased that when annual precipitation was higher than the critical value. Therefore,the critical value might help to explain the difference in contribution rates of vegetation restoration to runoff in different watersheds and serve as one of the important reasons for the debate and divergence of forest restoration impacts on runoff.
作者
刘政
叶晶萍
欧阳磊
盛菲
刘士余
LIU Zheng, YE Jing-ping, OUYANG Lei, SHENG Fei, LIU Shi-yu(College of Land Resources and Environment, Jiangxi Agricultural University/Jiangxi Province Key Laboratory of Poyang Lake Watershed Agricultural Resources and Ecology, Nanchang 330045, China)
出处
《应用生态学报》
CAS
CSCD
北大核心
2018年第11期3705-3711,共7页
Chinese Journal of Applied Ecology
基金
国家自然科学基金项目(31460222)资助~~
关键词
彭冲涧小流域
降水变化
植被恢复
经验统计分析法
临界值
Pengchongjian small watershed
precipitation variation
vegetation restoration
empirical statistics analysis method
critical value.