Study On Effects Of Micro Environment On Soil Respiration Of Evergreen Broad-leaved Forest In WuYi National Nature Reserve

Soil respiration in ecosystems plays an important role in global carbon cycle.The change of forest soil respiration will bring powerful influence on the terrestrial ecosystems and global carbon balances.Heterogeneity is one of the important characteristics of soil respiration.The main impact factors of forest soil respiration heterogeneity,such as:species,environment,and so on.Study shows that the distance from the plant can also affect the soil respiration.In order to expound the effects of these impact factors on soil respiration,this paper studies the changes of soil respiration from the micro environment.In this paper,the forest soil respiration,soil temperature and soil water content were determinate by the LI-8100 automated soil COZ flux system in WuYi Mountain on Jun,2013.Selecting the Castanopsis eyrei at 4 different altitudes(1000m,850m,715m and540m),the Cyclobalancopsis myrsinaefolia at 2different altitudes(1022m and 850m)and C.eyrei at 2 different altitudes(700m and570m),each population is divided into 7 ages(?,?,?,?,?,?,?).The results show that:1).There is no significant change of soil respiration rate about Castanopsis eyrei in different altitudes.The maximum of soil respiration rate is the rate at an altitude of 715 m,while the minimum of soil respiration is at the altitude of 1000 or 850m.2).There is no significance change of soil respiration rate of C.eyrei,C.carlesii and C.M in different ages.The ranges of C.eyrei soil respiration in different ages at 4 different altitudes are from 1.95to1.3?mol·m-2·s-1,2.25tol.4?mol·m-2·s-1,4.75to1.5?mol·m-2·s-1 and2.8to1.35 ?mol·m-2·s-1.And there is no significant change of soil respiration in different aged C.carlesii and C.M.The ranges of C.M's soil respiration in different ages are from 1.95to1.3?mol·m-2·s-1and 4.25to1.3 ?mol·m-2·s-1 at 2 different altitudes.The range of Ccarlesii's soil respiration in different ages are from 3.Oto 1.7?mol·m-Z·s-1 and 2.25to 1.3?mol·m-2·s-1 at 2 different altitudes.3).The main factors of soil respiration are air temperature,soil temperature and soil water content.There are significant exponential relations between soil respiration and air temperature of C.eyrei,C.carlesii and C.M(P<0.05).Air temperature can explain from 52%to 78%changes of soil respiration about C.eyrei at 4 different altitudes.Soil temperature can explain the soil respiration of C.eyrei from 58.25%to 95%changes at 4 different altitudes.And there are significant exponential relations between soil respiration and soil temperature of C.eyrei,C.carlesii and C.M(P<0.05).However,the relations of the 3 species between soil respiration and soil water content are not obvious(P>0.05).The study shows the space variation of soil respiration and the relationship between soil respiration and impact factors in WuYi Mountain.The main factor to explain the soil respiration in is soil temperature.The results will enrich the research of the global carbon cycle.