温度和湿度对高寒草甸凋落物分解的影响  

Effects of temperature and moisture on litter decomposition in an alpine meadow

作　　者：阿旺 吕汪汪 周阳[1,5] 孙建平 张苏人 夏露 李博文 刘培培[1,5] 洪欢 王奇 张立荣 苏爱玲[2] 姜丽丽 斯确多吉 张振华[2] 罗彩云[2] 汪诗平[1,3] A Wang;LÜ Wangwang;ZHOU Yang;SUN Jianping;ZHANG Suren;XIA Lu;LI Bowen;LIU Peipei;HONG Huan;WANG Qi;ZHANG Lirong;SU Ailing;JIANG Lili;TSECHOE Dorji;ZHANG Zhenhua;LUO Caiyun;WANG Shiping(Key Laboratory of Alpine Ecology,Institute of Tibetan Plateau Research,Chinese Academy of Sciences,Beijing 100101,China;Northwestern Institute of Plateau Biology,Chinese Academy of Sciences,Xining 810008,China;Chinese Academy of Sciences Center for Excellence in Tibetan Plateau Earth Science,Beijing 100101,China;College of Science,Tibet University,Lhasa 850000,China;University of Chinese Academy of Sciences,Beijing 100094,China)

机构地区：[1]中国科学院青藏高原研究所高寒生态重点实验室,北京100101 [2]中国科学院西北高原生物研究所,西宁810008 [3]中国科学院青藏高原地球科学卓越中心,北京100101 [4]西藏大学理学院,拉萨850000 [5]中国科学院大学,北京100094

出　　处：《生态学报》2021年第17期6846-6853,共8页Acta Ecologica Sinica

基　　金：国家基金委重点基金项目(41731175);中国科学院专项A(XDA20050101,XDA2005010405);国家重点研发项目(2016YFC0501802)。

摘　　要：多数研究发现增温增湿加快了凋落物失重率,但对如何影响凋落物分解过程中CO_(2)和可溶性有机碳(DOC)释放的影响研究较少。通过室内培养设置四个温度梯度(0,5,10和20℃)和两个湿度梯度(25%和40%)对高寒草甸凋落物分解进行了96 d的培养试验。结果表明,总体上高寒草甸凋落物分解速率随着温度和湿度的增加而加快;高湿度条件下凋落物分解释放CO_(2)总量的敏感性是低湿度的2.3倍左右;湿度变化对DOC淋溶的温度敏感性影响较小。在25%和40%的湿度培养下,CO_(2)总排放量的温度敏感性分别是DOC总淋溶量的温度敏感性的10和20倍左右,表明未来气候变化情境下凋落物中的有机质分解更多的是以CO_(2)形式排放到大气中。因此,未来需要更系统的研究不同气候变化情境下凋落物积累与分解、DOC淋溶和土壤碳库的动态变化,从而更好的理解这些生态系统碳循环过程的变化及其对气候变化产生的反馈作用和机制。Many studies focus on effects of temperature and moisture on litter mass loss rate,however,how they affect CO_(2)emission rate and leaching of dissolved organic carbon(DOC)during the litter decomposition is unclear.We conducted an incubation experiment with four temperature gradients(0,5,10 and 20℃)and two moistures(25%and 40%)using litter of alpine meadow for 96 incubation days.Our results showed that litter mass loss rate only increased with increases in temperature under high moisture.The temperature sensitivity of CO_(2)emission rate was 2.3 times under high moisture as that of low moisture.The effect of moisture on temperature sensitivity of DOC leaching was small.The temperature sensitivities of CO_(2)emission rate were about 10 and 20 times compared with that of DOC leaching under 25%and 40%moistures,respectively,suggesting that more CO_(2)could be emitted relative to DOC leaching under future climate change.Therefore,more studies are needed to explore how climate change affects CO_(2)emission and DOC leaching through litter decomposition and their underlying mechanisms in the future.

关 键 词：温度 湿度 凋落物失重率 CO_(2) 呼吸 可溶性有机碳 温度敏感性 高寒草甸 青藏高原 

分 类 号：S812[农业科学—草业科学]