Changes in individual plant traits and biomass allocation in alpine meadow with elevation variation on the Qinghai-Tibetan Plateau |
| |
Authors: | WeiLing Ma PeiLi Shi WenHua Li YongTao He XianZhou Zhang ZhenXi Shen SiYue Chai |
| |
Institution: | (1) The Institute of Wetland Ecology, School of Life Science, Nanjing University, Nanjing, 210093, China; |
| |
Abstract: | Plant traits and individual plant biomass allocation of 57 perennial herbaceous species, belonging to three common functional
groups (forbs, grasses and sedges) at subalpine (3700 m ASL), alpine (4300 m ASL) and subnival (⩾5000 m ASL) sites were examined
to test the hypothesis that at high altitudes, plants reduce the proportion of aboveground parts and allocate more biomass
to belowground parts, especially storage organs, as altitude increases, so as to geminate and resist environmental stress.
However, results indicate that some divergence in biomass allocation exists among organs. With increasing altitude, the mean
fractions of total biomass allocated to aboveground parts decreased. The mean fractions of total biomass allocation to storage
organs at the subalpine site (7%±2% S.E.) were distinct from those at the alpine (23%±6%) and subnival (21%±6%) sites, while
the proportions of green leaves at all altitudes remained almost constant. At 4300 m and 5000 m, the mean fractions of flower
stems decreased by 45% and 41%, respectively, while fine roots increased by 86% and 102%, respectively. Specific leaf areas
and leaf areas of forbs and grasses deceased with rising elevation, while sedges showed opposite trends. For all three functional
groups, leaf area ratio and leaf area root mass ratio decreased, while fine root biomass increased at higher altitudes. Biomass
allocation patterns of alpine plants were characterized by a reduction in aboveground reproductive organs and enlargement
of fine roots, while the proportion of leaves remained stable. It was beneficial for high altitude plants to compensate carbon
gain and nutrient uptake under low temperature and limited nutrients by stabilizing biomass investment to photosynthetic structures
and increasing the absorption surface area of fine roots. In contrast to forbs and grasses that had high mycorrhizal infection,
sedges had higher single leaf area and more root fraction, especially fine roots. |
| |
Keywords: | Qinghai-Tibetan Plateau climate stress biomass allocation shoot/root ratio plant traits fine roots |
本文献已被 PubMed SpringerLink 等数据库收录! |
| 点击此处可从《中国科学:生命科学英文版》浏览原始摘要信息 |
| 点击此处可从《中国科学:生命科学英文版》下载免费的PDF全文 |
|