Biomass Allocation Patterns of Alpine Grassland Species and Functional Groups along a Precipitation Gradient on the Northern Tibetan Plateau

• Published in: Journal of mountain science 2013-12, Vol.10 (6), p.1097-1108
• Main Authors: Wu, Jian-shuang, Shen, Zhen-xi, Zhang, Xian-zhou, Shi, Pei-li
• Format: Article
• Language: English
• Subjects: Alpine environments; Biodiversity; Biomass; Deserts; Earth and Environmental Science; Earth Sciences; Ecology; Environment; Geography; Grasslands; Growing season; Plant ecology; Resource availability; Steppes; 分配格局; 功能群; 单株生物量; 物种; 生物质组分; 藏北高原; 降水梯度; 高寒草地
• ISSN: 1672-6316; 1993-0321; 1008-2786
• DOI: 10.1007/s11629-013-2435-9

Variations in the fractions of biomass allocated to functional components are widely considered as plant responses to resource availability for grassland plants. Observations indicated shoots isometrically relates to roots at the community level but allometrically at the species level in Tibetan alpine grasslands. These differences may result from the specific complementarity of functional groups between functional components, such as leaf, root, stem and reproductive organ. To test the component complementary responses to regional moisture variation, we conducted a multi-site transect survey to measure plant individual size and component biomass fractions of common species belonging to the functional groups： forbs, grasses, legumes and sedges on the Northern Tibetan Plateau in peak growing season in 2010. Along the mean annual precipitation （MAP） gradient, we sampled 7o species, in which 2o are in alpine meadows, 20 in alpine steppes, 15 in alpine desert-steppes and 15 in alpine deserts, respectively. Our results showed that the size of alpine plants is small with individual biomass mostly lower than 1.0 g. Plants keep relative conservative component individual responses moisture functional fractions across alpine grasslands at the level. However, the complementary between functional components to variations specifically differ among groups. These results indicate that functional group diversity may be an effective tool for scaling biomass allocation patterns from individual up to community level. Therefore, it is necessary andvaluable to perform intensive and systematic studies on identification and differentiation the influences of compositional changes in functional groups on ecosystem primary services and processes.