摘要
森林土壤呼吸是陆地生态系统土壤呼吸的重要组成部分,其动态变化对全球碳平衡有着重要的影响,然而目前对喀斯特地区原生林土壤呼吸的研究还比较薄弱。本研究通过对茂兰喀斯特原生林土壤呼吸的日、月动态变化监测,得出以下初步结论:1)茂兰喀斯特原生林土壤呼吸有着明显的日变化规律:白天土壤呼吸速率明显高于晚上(最高值出现在13∶00～15∶00),且雨季土壤呼吸日变化规律与旱季存在明显差异;2)喀斯特原生林土壤呼吸速率变化范围为140.3～920.6mg.m-2.h-1,且有着明显的月变化特征,即雨季的各月明显高于旱季时各个月份的土壤呼吸,年通量与南亚热带阔叶林无明显差异;3)茂兰喀斯特原生林仅在旱季土壤呼吸的日变化与气温有着显著的指数相关关系(R2=0.83,P<0.001),土壤呼吸的月变化或日变化(雨季)与土壤温度、湿度均无相关性。
Forest soil respiration in a terrestrial ecosystem is a very important part involved in the global carbon cycle.Understanding soil respiration is crucial both for the carbon balance of terrestrial ecosystems and the global carbon balance.However,few studies are focused on karst forest ecosystems.In order to investigate the soil respiration rate,the Maolan Biosphere Reserve as a natural karst forest was chosen for this study.Our results showed that distinctly monthlyl and diurnal variations of soil respiration rates（ranging from 140.3 mg·m-2·h-1 to 920.6mg·m-2·h-1） were observed;soil respiration in each month during the wet seasons was higher than that during the dry seasons;there was no difference between the total released CO2 flux in this study and in subtropical broad-leaved forests;during the daytime the soil respiration（the maximum was found at 13∶00~15∶00） was significantly higher than that during the night time;obvious differences were observed in the diurnal variation of soil respiration between the wet seasons and the dry seasons.The soil respiration was correlated with air temperature during the dry seasons（R2=0.83,P0.001）.There was no relationship between the variations of soil respiration and soil temperature as well as soil water contents during the wet seasons.
出处
《地球与环境》
CAS
CSCD
北大核心
2011年第3期313-317,共5页
Earth and Environment
基金
中国科学院知识创新工程方向性项目(kzcx2-yw-306)
国家自然科学基金创新群体项目(40721002)
贵州省科技基金资助项目(黔科合J字[2008]2014)
关键词
土壤呼吸
温度
湿度
喀斯特森林
soil respiration
temperature
soil water content
karst forest
