雪被斑块对川西高山森林凋落叶N和P释放的影响  

Effects of snow patches on the release of N and P during foliar litter decomposition in an alpine forest of western Sichuan,China

作　　者：何洁[1] 蒋先敏 杨万勤[1] 倪祥银[1] 徐李亚 李晗[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,成都611130 [2]四川省川西林业局,四川理县623102

出　　处：《应用生态学报》2014年第8期2158-2166,共9页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金项目(31270498;31170423);"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特别项目(2012T50782)资助

摘　　要：采用凋落物网袋法,研究冬季不同关键时期雪被斑块对川西高山森林6种代表性树种凋落物分解过程中N和P释放的影响.结果表明:整个雪被覆盖季节凋落物N表现为富集,P表现为释放,且雪被融化期P释放速率最大.厚型和中型雪被斑块下凋落物P释放速率大于薄型和无雪被斑块,而薄型和无雪被斑块下凋落物的N释放速率明显较高.6种凋落物N释放率和释放速率与日均温呈显著负相关;除岷江冷杉外,其他树种凋落物P释放率和释放速率与日均温表现为正相关.气候变暖情景下冬季雪被覆盖的减小将促进高山森林冬季凋落物分解过程中N释放,抑制P释放.A field experiment using litterbags was conducted in an alpine forest of western Sichuan in order to understand the effects of snow patches on the dynamics of N and P during decomposition of six representative species foliar litter in different periods of winter. Net N immobilization during foliar litter decomposition was observed in the whole snow cover season regardless of species. In contrast, P mainly released from foliar litter in the snow cover season, with a rapid rate of P release in the snow melt stage. Thick and moderate snow patches showed higher P release rates, but lower N release rates of foliar litter. The rate of N release was negatively related to daily mean temperature regardless of species, but the rate of P release was positively related to daily mean temperature with the exception of fir needle litter. The decrease of snow cover in the scenario of global warming could inhibit P release but promote N release from foliar litter decomposition in winter in the alpine forest.

关 键 词：高山森林 凋落物分解 释放动态 雪被斑块 

分 类 号：S718.5[农业科学—林学]