秦岭火地塘3种主要林型林冠层对不同pH值降雨水质的影响  

Effects of Canopy of Three Main Forest Types on Rainfall Water Quality With Different pH Values in Huoditang Forest Area of Qinling Mountains

作　　者：高晓晓 张胜利[2,3] 邱志斌 潘泰臣 于金鑫 Gao Xiaoxiao;Zhang Shengli;Qiu Zhibin;Pan Taichen;Yu Jinxin(Institute of Soil and Water Conservation,Northwest A&F University,Yangling,Shaanxi 712100,China;College of Resources and Environment,Northwest A&F University,Yangling,Shaanxi 712100,China;Qinling Forest Ecosystem National Field Research Station,Yangling,Shaanxi 712100,China;Guangxi Environmental Emergency and Accident Investigation Center,Nanning,Guangxi 530028,China;Power China Zhongnan Survey,Design and Research Institute Co.,Ltd.,Changsha,Hu’nan 410014,China)

机构地区：[1]西北农林科技大学水土保持研究所,陕西杨凌712100 [2]西北农林科技大学资源环境学院,陕西杨凌712100 [3]陕西秦岭森林生态系统国家野外科学观测研究站,陕西杨凌712100 [4]广西壮族自治区环境应急与事故调查中心,广西南宁530028 [5]中国电建集团中南勘测设计研究院有限公司,湖南长沙410014

出　　处：《水土保持通报》2021年第3期103-109,209,共8页Bulletin of Soil and Water Conservation

基　　金：中华人民共和国科学技术部“华山松优质建筑用材林高效培育技术研究”(2017YFD0600504-2);西北农林科技大学森林生态系统服务功能科研成果培育(Z102021809)。

摘　　要：[目的]研究秦岭火地塘林区3种主要林型林冠层对不同pH值降雨水质的影响过程,为研究酸沉降对森林生态系统的影响提供基础。[方法]以林区油松林、华山松林、锐齿栎林为研究对象,自制人工降雨器模拟降雨,分析各林分林冠穿透雨水化学物质浓度随降雨时间及降雨酸度的变化规律。[结果]①模拟降雨10 min或20 min 3种林分林冠穿透雨中NH4^(+),NO3^(-),K+,Ca^(2+),Mg^(2+),Pb,Zn,Cd浓度达到峰值,降雨20~30 min后浓度降低并趋于稳定,随降雨时间延长总体上呈先升高后降低并趋于稳定的规律。②针叶林、阔叶林不同的叶组织特性影响林冠中化学物质淋洗量。相同pH值降雨淋洗,油松、华山松林冠穿透雨中NH4^(+),NO3^(-),K+,Ca^(2+),Mg^(2+),Pb,Zn,Cd浓度多表现为大于锐齿栎。③酸雨能促进林冠中化学物质淋失。对于同一树种,不同pH值降雨淋洗,林冠穿透雨中NH4^(+),K+,Ca^(2+),Mg^(2+),Pb,Cd浓度值及浓度变化幅度大小大体表现为:pH 4.0>pH 5.0>pH 7.0。[结论]根据林冠穿透雨水化学物质浓度随降雨时间动态变化规律,将林冠对穿透雨水质影响过程划分为降雨淋洗(降雨开始至降雨10 min或20 min)和降雨淋溶(降雨约20~30 min以后)两个阶段。降雨淋洗阶段,林冠层对水质变化影响大。[Objective]The effects of forest canopy type on water quality of rainfall with different pH values were studied in order to provide a basis for studying the effects of acid rainfall on forest ecosystems in the Huoditang forest area of the Qinling Mountains.[Methods]A self-made artificial rainfall device was used to simulate rainfall on three main forest types(Pinus tabuliformis,Pinus armandii,and Quercus aliena var.acuteserrata).Changes in the concentration of rainwater chemicals in the canopy of each forest were analyzed by rainfall time and rainfall acidity.[Results]①The concentrations of NH4^(+),NO3^(-),K+,Ca^(2+),Mg^(2+),Pb,Zn,and Cd in the throughfall of the three forests canopies reached peak values after 10—20 minutes,and the concentration decreased and stabilized after 20—30 min of rainfall.The concentrations generally increased first,and then decreased and tended to be stable with the extension of rainfall time.②The different leaf tissue characteristics of the conifer forest and the broadleaved forest affected the leaching amount of chemicals in forest canopies.With the same pH value,the concentrations of NH4^(+),NO3^(-),K+,Ca^(2+),Mg^(2+),Pb,Zn,and Cd in the throughfall were higher in P.tabuleformis and P.armandii than in Q.acuminata.③Acid rain can promote the loss of chemicals in forest canopies.For the same tree species,with different pH values of leaching rain,the concentrations of NH4^(+),K+,Ca^(2+),Mg^(2+),Pb,and Cd in canopy throughfall and the variation range of their concentrations generally followed the order of pH 4.0>pH 5.0>pH 7.0.[Conclusion]According to the dynamic change process of chemical substance concentration of canopy throughfall with rainfall time,the impact process of canopy on throughfall water quality can be divided into two stages:rainfall washing(rainfall of about 10—20 minutes)and rainfall leaching(rain starts to 10 or 20 minutes later).In the rainfall washing stage,the canopy has a great influence on the water quality.

关 键 词：油松林 华山松林 锐齿栎林 林冠层 降雨水质 pH值 

分 类 号：S715.3[农业科学—林学]