文献类型：期刊文献

英文题名：Specific leaf area predicts dryland litter decomposition via two mechanisms

作者：Liu, Guofang[1] Wang, Lei[2] Jiang, Li[2] Pan, Xu[3] Huang, Zhenying[1] Dong, Ming[1,4] Cornelissen, Johannes H. C.[5]

第一作者：Liu, Guofang

通信作者：Huang, ZY[1]

机构：[1]Chinese Acad Sci, State Key Lab Vegetat & Environm Change, Inst Bot, Beijing, Peoples R China;[2]Chinese Acad Sci, State Key Lab Desert & Oasis Ecol, Xinjiang Inst Ecol & Geog, Urumqi, Peoples R China;[3]Chinese Acad Forestry, Inst Wetland Res, Beijing, Peoples R China;[4]Hangzhou Normal Univ, Key Lab Hangzhou City Ecosyst Protect & Restorat, Coll Life & Environm Sci, Hangzhou, Zhejiang, Peoples R China;[5]Vrije Univ Amsterdam, Syst Ecol, Dept Ecol Sci, Fac Sci, Amsterdam, Netherlands

年份：2018

卷号：106

期号：1

起止页码：218-229

外文期刊名：JOURNAL OF ECOLOGY

收录：;Scopus(收录号：2-s2.0-85037999671);WOS:【SCI-EXPANDED(收录号:WOS:000417839700018)】；

基金：State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Grant/Award Number: G2014-02-02; the National Key Research and Development Program of China, Grant/Award Number: 2016YFC0500501; National Natural Science Foundation of China, Grant/Award Number: 31470712

语种：英文

外文关键词：desert; functional traits; litter decomposition rate; photodegradation; plant-soil (below-ground) interactions; soil burial; specific leaf area

摘要：Litter decomposition plays important roles in carbon and nutrient cycling. In dryland, both microbial decomposition and abiotic degradation (by UV light or other forces) drive variation in decomposition rates, but whether and how litter traits and position determine the balance between these processes is poorly understood. We investigated relationships between litter quality and their decomposition rates among diverse plant species in a desert ecosystem in vertically contrasting positions representing distinct decomposition environments driven by different relative contributions of abiotic and microbial degradation. Thereto, leaf litter samples from 17 desert species were sealed into litterbags and placed on the soil surface under strong solar exposure vs. shade conditions, or buried in the soil at 10cm depth, for a whole year. Litter decomposition rates were 21% and 17% higher in burial and light-exposed treatments, respectively, than those in shade. Leaf traits, i.e. specific leaf area (SLA), litter C:N ratio and lignin concentration could predict litter decomposition to some degree, but their predictive power was dependent on litter position. However, multiple linear regressions showed that SLA, litter C and P significantly affected k values for leaf litter decomposition besides litter position, with SLA standing out as a strong determinant of litter decomposition rate as related either to solar radiation or the environment below the soil surface. Furthermore, the interspecific differences in litter decomposition rates decreased over time, implying that afterlife effects of leaf traits on decomposition were attenuated.Synthesis. These findings suggest that abiotic photodegradation and soil burial mediated microbial decomposition could be responsible for higher than expected litter turnover in dryland. They point to a dual role of specific leaf area (SLA) as a promotor of decomposition rates: via relative exposure of the leaf surface to abiotic factors such as UV light vs. to soil moisture and microbes under soil burial.