摘要
利用Granier热扩散植物液流技术(TDP),于2012年5—9月连续对大兴安岭北部兴安落叶松蒸腾进行测定,结合同步观测的环境因子,分析兴安落叶松树干液流规律及其与环境因子的关系。结果表明:1)兴安落叶松蒸腾速率具有明显的昼夜变化规律,晴天和阴天均为单峰曲线,雨天为双峰曲线,且晴天和阴天的蒸腾速率高于雨天。夜间液流通量占整日液流通量的百分比为晴天(5.91%)>雨天(4.88%)>阴天(2.57%),在高温无雨情况下,液流通量呈现随高温无雨日数的增加而逐渐降低的趋势。2)6—8月兴安落叶松蒸腾量占观测期总耗水量的80%,液流密度日峰值较高,其中7月最高达23.62cm3/(cm2·h),5月次之,9月最低为2.03cm3/(cm2·h)。3)边材液流密度与环境因子存在良好的相关性,多元回归模型决定系数为0.79;影响兴安落叶松树干液流的主要影响因子为蒸汽压亏缺和光合有效辐射。4)生长季内兴安落叶松林蒸腾耗水量为566.49t/hm2,即56.65mm,占同期降雨量的12%。
In this study, by Granier thermal dissipation probe （TDP） method, Larix gmelinii transpiration was continuously observed in northern Da Hinggan Mountains, northeastern China from May to September in 2012. Integrated with simultaneous environmental factors, transpiration of L. gmelinii and its relationship with influencing factors were investigated. The results showed that： 1 ） L. gmelinii transpiration rate showed significant diurnal variations, which presented unimodal curves in sunny and cloudy days, and bimodal or muhimodal curves in rainy days, respectively. Transpiration rates of sunny and cloudy days were higher than those of rainy days. The ratio list of night sap flow flux accounting for a full day＇s flow flux was： sunny day（5.91%） 〉 rainy day （4. 88%） 〉 cloudy day（2.57%）. In the case of high temperature and no rain, the sap flow presented a decreasing trend with the rainless and hot days increasing. 2） Daily peak of L. gmelinii sap flow rate was high in June to August, and it reached the highest value of 23.6 cm3/（ cm2- h） in July, the transpiration in June to August accounted for 80% of the total water consumption during observation period. The daily peak in May was less and it got the lowest value of 2.03 cm3/（cm/ -h） in September. 3） Good correlation existed between sap flow rate and environmental factors, just as the coefficient of determination of their multiple regression model was 0.79. Further correlation analyses indicated that main environmental factors influencing sap flow density in the growing season were vapor pressure deficit and photosynthetic active radiation. 4） The total transpiration of L. gmelinii stand during the growing season was 566.49 t/hm2 , i.e. 56.65 mm, accounted for 12% of rainfall in the same period.
出处
《北京林业大学学报》
CAS
CSCD
北大核心
2013年第4期21-26,共6页
Journal of Beijing Forestry University
基金
林业公益性行业科研专项(201104005-05)
"东北林业大学学术名师支持计划"项目
关键词
Granier热扩散法
兴安落叶松
树干液流
环境因子
林分蒸腾量
Granier＇ s thermal dissipation probe method
Larix gmelinii
stem sap flow
environmentalfactors
stand transpiration
