洪泽湖河湖交汇区典型杨树人工林碳通量月尺度变化特征  

Monthly scale variation characteristics of net ecosystem exchange (NEE) in poplar plantations at the confluence of Hongze Lake and Huai River

作　　者：崔皓 韩建刚 郭俨辉[1] 季淮 朱咏莉 李萍萍 CUI Hao;HAN Jiangang;GUO Yanhui;JI Huai;ZHU Yongli;LI Pingping(College of Biology and the Environment,Nanjing Forestry University,Nanjing 210037,China;Co-Innovation Center for the Sustainable Forestry in Southern China,Nanjing Forestry University,Nanjing 210037,China;National Positioning Observation Station of Hongze Lake Wetland Ecosystem in Jiangsu Province,Hongze 223100,China)

机构地区：[1]南京林业大学生物与环境学院,江苏南京210037 [2]南京林业大学南方现代林业协同创新中心,江苏南京210037 [3]江苏洪泽湖湿地生态系统国家定位观测研究站,江苏洪泽223100

出　　处：《南京林业大学学报（自然科学版）》2022年第2期19-26,共8页Journal of Nanjing Forestry University：Natural Sciences Edition

基　　金：林业科技成果国家级推广项目([2016]37号)。

摘　　要：【目的】揭示洪泽湖水位夏低冬高的独特水文特点对河湖交汇区杨树人工林净生态系统碳交换(NEE,简称碳通量)产生的影响。【方法】采用涡度相关及土壤水热监测系统,对洪泽湖湿地河湖交汇区典型杨树人工林碳通量及其环境因子进行了连续3 a(2016—2018年)的观测,分析月尺度上碳通量变化及其与环境因子的关系。【结果】(1)洪泽湖河湖交汇区杨树人工林的NEE值具有明显“V”形变化曲线,白天表现为碳吸收,夜间表现为碳释放,日均碳汇时间为10 h;(2)研究期间各旬NEE值在2018年的2月上旬最高(7.117 g/m^(2)),最低值出现在2017年的7月中旬(-212.256 g/m^(2));3年间年均NEE值为-1 413.403 g/m^(2);(3)在洪泽湖开闸时期(5—8月)水位低,土壤含水率和风速是影响NEE的主要因素,关闸时期(9月至翌年4月)水位高,NEE主要受空气温度和饱和水汽压差影响。【结论】夏季对洪泽湖开闸放水,有利于河湖交汇区杨树生长及碳汇增加,冬季蓄水地下水位抬高,对杨树生长产生的不利影响可以通过开沟筑垄来消除,进而有利于区域杨树人工林全年碳汇功能的提升。【Objective】The aim of this study was to reveal the impact of the unique hydrological characteristics of Hongze Lake, which has a low water level in summer and a high water level in winter, on the net ecosystem exchange carbon flux(NEE) of poplar plantations at the confluence of Hongze Lake and Huai River. 【Method】In this study, eddy covariance and soil moisture monitoring systems were used to observe the NEE and environmental factors of typical poplar plantations in the river-lake intersection area for three consecutive years(2016-2018) to analyze the variations in NEE and its relationship with environmental factors on a monthly basis. 【Result】(1) The NEE values of the poplar plantations in this area displayed an obvious V-shaped curve, showing carbon absorption during the daytime and carbon release at night, with an average daily carbon sink time of 10 h.(2) The highest value of NEE during the annual 10 days study was 7.117 g/m^(2)in early February 2018, and the lowest NEE was-212.256 g/m^(2)in mid-July 2017. The average annual NEE value in the three years was-1 413.403 g/m^(2).(3) The water level of Hongze Lake was low during the sluice-opening period(from May to August), and soil moisture content and wind speed were the main factors affecting NEE, whereas the water level was high during the sluice-closing period(September to April of the next year), and NEE was mainly affected by air temperature and saturated vapor pressure differences. 【Conclusion】Opening the sluices and releasing water in summer were advantageous for the growth of poplar trees and increased the carbon sink. In winter, the groundwater level increased, and the adverse effects on the poplar growth could be eliminated by the ditching and ridge construction, which would be beneficial for improving the annual carbon sink function of poplar plantations in this region.

关 键 词：杨树人工林 碳通量 涡度相关 环境因子 洪泽湖 

分 类 号：X826[环境科学与工程—环境工程] S718[农业科学—林学]