干旱条件下北方典型人工林生态系统水量平衡及其影响因素  

Water balance and influencing factors in typical plantation ecosystems in northern China under drought conditions

作　　者：赵家辰 贾剑波[3] 贾国栋[1,2] 陈立欣[1,2] ZHAO Jia-chen;JIA Jian-bo;JIA Guo-dong;CHEN Lixin(Key Lab of Soil and Water Conservation&Desertification Combating,State Forestry and Grassland Administration,College of Soil and Water Conservation,Beijing Forestry University,Beijing 100083,China;Beijing Engineering Research Center of Soil and Water Conservation,Beijing Forestry University,Beijing 100083,China;College of Forestry,Central South University of Forestry and Technology,Changsha 410004,China)

机构地区：[1]北京林业大学水土保持学院国家林业和草原局水土保持与荒漠化防治重点实验室,北京100083 [2]北京林业大学北京市水土保持工程技术研究中心,北京100083 [3]中南林业科技大学林学院,长沙410004

出　　处：《生态学杂志》2019年第11期3254-3263,共10页Chinese Journal of Ecology

基　　金：国家自然基金项目(4187070354);国家科技支撑计划项目(2015BAD07B06);北京林业大学青年教师科学研究中长期项目任务(2015ZCQ-SB-03)资助

摘　　要：为探究北方典型人工林生态系统在干旱条件下的水量平衡及其影响因素,本研究分析了干旱年份(2014年)北京山区油松(Pinus tabuliformis)和侧柏(Platycladus orientalis)林分的水量平衡组分及其影响因素。结果表明:2014年降水仅为多年(1958-2011年)平均的47%。蒸腾为两种林分最大水分输出项,油松为247.16 mm,侧柏为259.89 mm。其余水分输出项依次为土壤蒸发(油松87.26 mm,侧柏60.02 mm)>林冠截留(油松56.63 mm,侧柏50.23 mm)>枯落物蒸发(油松9.99 mm,侧柏8.30 mm)。两种林分土壤水补给整体为亏缺状况,仅在生长季中、后期出现水分补给。油松林生态系统年水分亏缺量为81.24 mm,侧柏林生态系统为67.45 mm。环境因子对水分输出各项影响显著。此外,蒸腾还与胸径有显著相关,林冠截留则受到郁闭度及风速的共同影响。根据本研究观测,侧柏和油松林分在干旱年份无法仅依靠自然降水维持水量平衡。因此,未来气候变化导致降水减少情境会对这些林分的自然存活带来较大挑战。To explore water balance and influencing factors in typical plantation ecosystems under drought conditions in northern China,we analyzed water balance components and influencing factors in Pinus tabuliformis and Platycladus orientalis plantations in Beijing mountain region in a dry year( 2014). The results showed that the rainfall in 2014 was only 47% of long-term mean value( 1958-2011). Transpiration accounted for the highest proportion of total water loss in both forests. The stand transpiration of P. tabuliformis and P. orientalis plantations was 247. 16 and 259.89 mm,respectively. The other water loss pathways ranked following the order: soil evaporation( P. tabuliformis,87.26 mm;P. orientalis,60.02 mm) > canopy interception( P. tabuliformis,56.63 mm;P. orientalis,50.23 mm) > litter evaporation( P. tabuliformis,9.99 mm;P.orientalis,8.30 mm). Soil water was at a state of the annual deficit but was replenished during the second half of the growing season. The annual water deficit of the P. tabuliformis and P. orientalis stands was 81.24 and 67.45 mm,respectively. Stand water loss was significantly affected by environmental factors. Meanwhile,transpiration was significantly correlated with the stand diameter at breast height. Canopy interception was affected by canopy closure and wind speed. In conclusion,with precipitation as the single water source,water balance in both P. tabuliformis and P. orientalis stands cannot be met during a dry year. Therefore,these stands will face substantial survival challenge associated with precipitation reduction under climate change.

关 键 词：枯落物截留 蒸腾 土壤蒸发 水分亏缺 

分 类 号：S71[农业科学—林学]