亚热带常绿阔叶林凋落叶分解过程中氮和磷在不同雨热季节的释放动态  

Dynamics of nitrogen and phosphorus release in decomposing foliar litter at different rainy stages in the subtropical evergreen broad-leaved forest

作　　者：马志良[1] 高顺[1] 杨万勤[1] 吴福忠[1] 

机构地区：[1]四川农业大学生态林业研究所,四川省林业生态工程省级重点实验室,华西雨屏区森林生态系统定位研究站,成都611130

出　　处：《应用与环境生物学报》2015年第2期308-315,共8页Chinese Journal of Applied and Environmental Biology

基　　金：国家自然科学基金项目(3117023;31200474);"十二五"国家科技支撑计划项目(2011BAC09B05);四川省杰出青年学术与技术带头人培育项目(2012JQ0008;2012JQ0059);中国博士后科学基金项目(7013M540714)资助~~

摘　　要：为理解植物—土壤之间的养分联系,采用凋落物分解袋法,研究季节性降雨期间常绿阔叶林区最具代表性的马尾松(Pinus massoniana)、柳杉(Cryptomeria fortunei)、杉木(Cunninghamia lanceolata)、香樟(Cinnamomum camphora)、红椿(Toona ciliata)、麻栎(Quercus acutissima)等6种凋落叶第一年不同雨热季节分解中氮(N)、磷(P)动态及释放与富集特征.结果显示,凋落叶的N浓度随雨季的变化动态取决于树种,但除红椿以外的其它5种凋落叶在分解初期N浓度变化不明显,在雨季时期显著升高(P<0.05);6种凋落叶P浓度动态比较一致,表现为分解初期P浓度稍微下降,在雨季时期显著升高(P<0.05).历经一年的分解,红椿N、P释放率最大(分别为81.79%、54.19%),香樟N富集率最大(131.45%),马尾松的P富集率最高(268.75%),且6种凋落叶N、P释放/富集率动态均在雨季最明显.凋落叶分解过程中C/N、C/P呈现下降趋势,而N/P变化规律不一致.这些结果均表明,季节性降雨显著(P<0.05)影响凋落叶N、P动态,雨季温湿度的改变可影响N、P释放过程.A comprehensive investigating of the dynamics of nitrogen （N） and phosphorus （P） releases in decomposingfoliar litter at different rainy stages will be helpful to understanding of the nutrient connections between plants and soils. The dynamics of the concentrations, releases and accumulations of N and P in the decomposing foliar litter of Pinus massoniana, Cryptomeria fortunei, Cunninghamia lanceolata, Cinnamomum camphora, Toona ciliate, and Quercus acutissima were investigated using the method of litterbag at different rainy stages during the first decomposing year. The results showed that dynamic changes of N concentrations in decomposing foliar litter depended on tree species. Except for T. ciliate, the N concentrations of the other five tree species changed slightly in foliar litter, but increased significantly （P 〈 0.05） in the rainy season. Regardless of tree species, the P concentrations decreased slightly in foliar litter, but increased significantly （P 〈 0.05） in the rainy season. After one year of decomposition experiment, foliar litter of T. ciliate released about 81.79% of N and 54.19% of P, respectively. However, foliar litter of C. camphora enriched 131.45% of N, and foliar litter of P. massoniana enriched 268.75% of P. On the whole, the dynamics of releases and enrichments of N and P in foliar litter occurred in rainy season regardless of tree species. The ratios of C to N and C to P in foliar litter declined in decomposing litter, but the ratio of N to P showed an uncertain dynamics. The results indicated that seasonal rainfall has a significant effect （P 〈 0.05） on N and P dynamics in decomposing foliar litter, and the changes of temperature and humidity in the rainy season would affect N and P release processes.

关 键 词：季节性降雨 亚热带常绿阔叶林 凋落叶分解 养分释放 

分 类 号：S714[农业科学—林学]