气温和空气相对湿度对森林地表细小死可燃物平衡含水率和时滞的影响  

Effects of air temperature and relative humidity on equilibrium moisture content and time-lag of forest land surface dead fine fuels

作　　者：胡海清[1] 陆昕[1] 孙龙[1] 曲智林[2] 梁宇[1] 李海洋[1] 

机构地区：[1]东北林业大学林学院,哈尔滨150040 [2]东北林业大学理学院,哈尔滨150040

出　　处：《植物生态学报》2016年第3期221-235,共15页Chinese Journal of Plant Ecology

基　　金：国家林业公益性行业科研专项(2014-04402);中央高校基本科研业务费专项资金项目(2572014AA22)

摘　　要：以落叶松(Larix gmelinii)叶片、白桦(Betula platyphylla)叶片、落叶松-白桦叶片混合物为例,初步研究了气温和空气相对湿度对地表细小死可燃物平衡含水率和时滞的影响,对这3种可燃物在不同气温、不同空气相对湿度条件下(共20个温湿度组合)失水过程中的含水率进行了测定。通过统计软件建立了相应条件下3种类型可燃物含水率时间动态方程,并利用此方程估算了3种可燃物平衡含水率和时滞,同时用估算值分别建立了3种可燃物的平衡含水率-气温模型、平衡含水率-湿度模型、时滞-气温模型、时滞-湿度模型等4种模型。并用已知的4个可燃物平衡含水率模型拟合了该研究得到的平衡含水率数据,其中,用Van Wanger模型得到的平均绝对误差和均方根误差均不超过0.01,拟合效果最好;Nelson模型的拟合效果最差。对气温和空气相对湿度对3种可燃物平衡含水率和时滞的影响的研究结果表明:气温和空气相对湿度对3种可燃物的平衡含水率和时滞有显著影响,气温与平衡含水率和时滞呈负相关关系,而空气相对湿度与二者均呈正相关关系。其中,时滞-湿度模型高估了可燃物的时滞。该研究具有一定的局限性与不确定性,在未来的工作中,应选择在更宽的可燃物类型范围内,结合更全面的影响因子进行研究。Aims This study was conducted to determine the effects of air temperature and relative humidity on the equilibrium moisture content （EMC） and time-lag of forest dead fine fuels by taking Larix gmelinii leaves, Betula platyphylla leaves and mixture of L. gmelinii and B. platyphylla leaves as examples. Methods Measurements were made on moisture content of fuels under different air temperature and humidity conditions （a total of 20 temperature by relative humidity combinations）. Equations describing the dynamics of moisture content of fme-grain fuels in three types of forests were developed and the EMC and time-lag were esti- mated. The moisture-time mode, EMC-temperature and EMC-relative humidity models, time-lag-temperature and time-lag-relative humidity models for fine-grain fuels were also established. Important findings Data were fit by four EMC models. The Van Wanger model gave the best fit with small er- rors （both mean absolute error （MAE） and root mean square error （RMAE） within 0.01）; the performance of Nel- son model was worst. Further analysis revealed that both air temperature and relative humidity significantly affected EMC and time-lag. Air temperature was negatively correlated with EMC and time-lag, whereas relative humidity was positively correlated with EMC and time-lag. Using the time-lag-relative humidity model overestimated the time-lag. There are some uncertainties and limitations remaining in the current analysis, and further research is needed on both desorption and absorption processes of fine fuels, with broader range of fuel types and more influencing factors.

关 键 词：平衡含水率 含水率 细小死可燃物 空气相对湿度 气温 时滞 

分 类 号：S762[农业科学—森林保护学]