科尔沁沙地南缘樟子松林蒸腾强度的年际变化及与降水、地下水位间的关系  

Inter-annual Variation of Transpiration Intensity of Pinus sylvestris var.mongolica Stand on the Southern Margin of Horqin Sandy Land and its Relationship with Precipitation and Groundwater Level

作　　者：韩辉 张学利 党宏忠[2] 徐贵军 张晓[2] 王斯彤 陈帅 张柏习 Han Hui;Zhang Xueli;Dang Hongzhong;Xu Guijun;Zhang Xiao;Wang Sitong;Chen Shuai;Zhang Baixi(Institute of Sandyland Management and Utilization Zhanggutai Desert Ecosystem Research Station,Fuxin 123000;Institute of Desertification,Chinese Academy of Forestry,Beijing 100091)

机构地区：[1]辽宁省沙地治理与利用研究所辽宁章古台科尔沁沙地生态系统国家定位观测研究站,阜新123000 [2]中国林业科学研究院荒漠化研究所,北京100091

出　　处：《林业科学》2020年第11期31-40,共10页Scientia Silvae Sinicae

基　　金：国家重点研发计划课题(2016YFC0500801);国家自然科学基金项目(32071836)。

摘　　要：【目的】通过连续、长期监测科尔沁沙地樟子松蒸腾过程,确定蒸腾用水量的年际变化规律及与降水、地下水位间的关系,明确樟子松的水分利用特征,为提高樟子松科学经营管理水平提供参考。【方法】利用热扩散式树干液流计对科尔沁沙地南缘章古台地区樟子松树干液流速率(J s)与林分生长过程开展为期9年(2010—2018年)的连续监测,并同步监测气象、地下水位、土壤水分等环境因子。【结果】中等密度的樟子松林(404株•hm^-2)生长季(4—10月)的多年平均蒸腾强度为163.7 mm•a^-1,最高为209.5 mm•a^-1。蒸腾强度的季节变化总体上可划分为上升期(4—7月)和下降期(7—10月)2个阶段,4、7、10三个月份的日均蒸腾强度(T s)分别为0.54、0.98和0.36 mm•d^-1,日蒸腾强度最高可达1.99 mm•d^-1。科尔沁沙地樟子松林分年蒸腾与年降水的比例(蒸/降比)多年平均为31.5%,在16.6%-54.7%间变动。在月尺度上,数据标准化后的樟子松蒸腾强度(T s)与月降水量(P r)、地下水位月均值(G)、太阳辐射月均值(PY)、0-60 cm层土壤体积含水率月均值(θ0-60 cm)间的回归关系式为:T s=0.04348+0.22299×P r-0.42464×G+1.20193×PY+0.30718×θ0-60 cm(R^2=0.58),太阳辐射对蒸腾强度的影响最大。【结论】科尔沁沙地南缘中等密度樟子松林分年蒸腾量约占年降水量的1/3,最多不超过55.0%。樟子松蒸腾能力(蒸腾强度与太阳辐射的比值)的年际变化总体上与由降水主导的从干变湿或由湿变干的水文年际变化趋势相符合,也与地下水位的年际变化规律基本吻合,但并不完全一致。【Objective】In this study,the inter-annual variation pattern of transpiration water consumption of Pinus sylvestris var.mongolica stand and its relationship with precipitation and groundwater level were determined by continuous and long-term field monitoring,which would clarify the water relationship of the tree species in sandy land,so as to provide reference for improving scientific management level of P.sylvestris var.mongolica.【Methods】The sap flow velocity(J s)of P.sylvestris var.mongolica plantation in the Zhanggutai area of the southern margin of Horqin sandy land was monitored continuously by thermal dissipation probe(TDP)methods for nine years from 2010 to 2018.Stand factors and environmental factors such as meteorology,groundwater level and soil volumetrical water content were simultaneously monitored.【Results】The multi-year transpiration intensity of the medium-density P.sylvestris var.mongolica s stand(404 trees•hm^-2)during the growing season(April to October)averaged 163.7 mm•a^-1 with the maximum of 209.5 mm•a^-1.In general,the transpiration intensity rose from April to July,and then declined from July to October.The daily average transpiration intensity in April,July and October was 0.54,0.98 and 0.36 mm•d^-1,respectively.The maximum intensity of daily transpiration over the whole study period was 1.99 mm•d^-1.The annual transpiration to annual precipitation ratio of P.sylvestris var.mongolica stand was 31.5%on average over the years,ranging from 16.6%to 54.7%.On a monthly scale,the normalized data of the transpiration intensity(T s)of P.sylvestris var.mongolica showed a linear relationship to monthly precipitation(P r),monthly average groundwater level(G),monthly average solar radiation(PY),and monthly average soil volumetric water content of 0-60 cm layer with a regression formula:T s=0.04348+0.22299×P r-0.42464×G+1.20193×PY+0.30718×θ0-60 cm(R^2=0.58).Solar radiation had the greatest influence on transpiration intensity.【Conclusion】The annual transpiration of P.sylv

关 键 词：液流 樟子松 降水量 蒸腾强度 地下水位 

分 类 号：S718.43[农业科学—林学]