元江干热河谷稀树灌丛凋落量动态特征  

Litterfall dynamic of a dry-hot valley savanna in Yuanjiang,southwest China

作　　者：熊壮 叶文 张树斌[2,3] 杨大新 XIONG Zhuang;YE Wen;ZHANG Shubin;YANG Daxin(School of Geography,Southwest Forestry University,Kunming,Yunnan 650224,China;Key Laboratory of Tropical Forest Ecology,Chinese Academy of Sciences,Mengla,Yunnan 666303,China;Yuanjiang Savanna Ecosystem Research Station,Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences,Yuanjiang,Yunnan 653300,China)

机构地区：[1]西南林业大学地理学院,云南昆明650224 [2]中国科学院热带森林生态学重点实验室,云南勐腊666303 [3]中国科学院西双版纳热带植物园元江干热河谷生态站,云南元江653300

出　　处：《森林与环境学报》2018年第4期439-443,共5页Journal of Forest and Environment

基　　金：国家自然科学基金项目(31600479);中国科学院西部之光项目(Y7XB081K01)

摘　　要：稀树灌丛植被广泛分布于我国西南干热河谷地区,然而,对其凋落量动态及影响因素的研究还比较缺乏。本文选取元江干热河谷稀树灌丛植被,开展凋落量动态监测,并分析其与主要气象因子的关系。结果表明:元江干热河谷年凋落总量为2 142.7 kg·hm^(-2);叶凋落量为1 561.5 kg·hm^(-2),占凋落总量的72.9%;枝、皮、花果、碎屑凋落量分别为284.9、18.9、172.4和105.0 kg·hm^(-2),分别占凋落总量的13.3%、0.9%、8.1%和4.9%。凋落总量的月动态呈现单峰型,从10月份开始气温和降雨量急剧降低,大部分植物在此时集中落叶,月凋落量达到峰值。月凋落量与月平均气温、月最高气温、月最低气温、月降雨量和土壤含水率等显著负相关(P<0.01),其中月降雨量是影响凋落量月动态的主要限制因素。Savanna is a widespread vegetation in dry-hot valley region,southwest China.However,the litterfall dynamic and their relations with meteorological factors are poorly understood.In the study,the litterfall dynamic of savanna ecosystem was monitored,and the relationships between litterfall dynamic and main meteorological factors were analyzed in Yuanjiang,Yunnan Province,southwest China.The results showed that the annual total litterfall yield was 2 142.7 kg·hm-2.Leaf litter accounted for 72.9%(1 561.5 kg·hm-2)of the total litterfall,and the branch,bark,flower&fruit,pieces were 284.9,18.9,172.4 and 105.0 kg·hm-2,which accounted for 13.3%,0.9%,8.1%and 4.9%,respectively.The monthly dynamic of litterfall yield showed mono-peak in October,namely,most plants shed leaves in October when the air temperature and precipitation decreased sharply.According to the correlation analysis with climate factors,the monthly litterfall productions were negatively correlated with mean air temperature,maximum air temperature,minimum air temperature,monthly precipitation and soil moisture content(P<0.01),which showed that monthly precipitation was the primary limiting factor affecting the monthly litterfall yield.

关 键 词：干热河谷 凋落 稀树灌丛 气象因子 

分 类 号：S718.5[农业科学—林学]