新闻动态

“青藏高原高寒草甸生态系统凋落物品质和不同海拔梯度气候变化对凋落物分解的影响”一文在Plant Ecology杂志上发表

2010-11-29  科技处

Guangping Xu, Yigang Hu, Shiping Wang, Zhenhua Zhang, Xiaofeng Chang, Jichuang Duan, Caiyun Luo, Zengguo Chao, Ailing Su, Qiaoyan Lin, Yingnian Li, Mingyuan Du. Effects of litter quality and climate change along an elevation gradient on litter mass loss in an alpine meadow ecosystem on the Tibetan plateau, Plant Ecol. 2010,209:257-268, IF=1.567

Abstract:

Knowledge of the response of litter mass loss to climate warming and litter quality in alpine ecosystems is still sparse. Here, we conducted a 507- day litter decomposition experiment along an elevation gradient from 3200 to 3800 m using different litter types to determine the influences of litter quality and climate change on the elemental mass losses and on the temperature sensitivity of litter mass losses (annual percentage decomposition (%) per 1_C temperature difference). Mass losses of C, nitrogen (N), phosphorus (P), potassium (K), sodium (Na), calcium (Ca), and Magnesium (Mg) decreased with an increase in elevation. In general, N and Na concentrations in litter and ratios of C:N and lignin:N were the best predictors of C mass losses. A higher N concentration and C:N ratio in litter caused greater C mass losses, but higher lignin:N ratio in litter resulted in lower C mass losses. Litter decomposition occurred in a two-stage process. Carbon mass loss in litter was mainly limited by soil temperature in the first growing season of the decomposition period, whereas N concentration and ratios of C:P and N:P limited carbon mass loss in the remaining litter during the second growing season of the decomposition period. Soil moisture appeared not to affect litter mass loss and the temperature sensitivity of litter mass loss of grass litter was greater than that of shrub litter in the alpine region.

Keywords:

Litter quality Mass loss  Soil temperature Soil moisture   Elevation gradient  Alpine meadow