TREE-LINE
; CLIMATE-CHANGE
; ALPINE TREELINE
; TEMPERATURE RECONSTRUCTION
; FOREST DISTRIBUTION
; SUMMER TEMPERATURE
; QILIAN MOUNTAINS
; GROWTH
; VARIABILITY
; DYNAMICS
WOS学科分类:
Forestry
WOS研究方向:
Forestry
英文摘要:
Most Tibetan people make their living through pastoralism, with livestock grazing being widespread throughout the Tibetan Plateau. The Tibetan Plateau is also home to the northern hemisphere's highest treelines but the effects of human activities, in particular pastoralism, on these treelines and their influence on the treeline responses to climate change remain unclear. To disentangle the effects of pastoral disturbances and climate on treeline dynamics, we surveyed three plots at grazing-disturbed Balfour spruce (Picea likiangensis var. balfouriana) treelines in the Yushu region (eastern Tibetan Plateau) and compared this data with published results of five undisturbed spruce treeline sites. Spatiotemporal changes in the position and structure of treelines during the past 400 years were reconstructed using dendrochronology. Tree recruitment was significantly linked to long-term summer and winter temperature. Under low local population densities and grazing pressure but consistent climate warming, disturbed treelines shifted upwards by 23.9-82.6 m during the 1611-1910 period. However, under higher local population densities, increased grazing pressure and climate warming over the last century, disturbed treelines showed no significant upward shift. In contrast, undisturbed treelines shifted upward by 25-68.5 m over the last century, thus implying that pastoralism was suppressing treeline expansion in disturbed sites. Together, these results underscore the importance of anthropogenic disturbances in influencing the structure and position of alpine treelines on the Tibetan Plateau. The role played by human disturbance should be carefully considered when evaluating the potential for treeline advance under future climate warming.
1.Nanjing Forestry Univ, Coll Biol & Environm, Nanjing 210037, Jiangsu, Peoples R China 2.Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, Bldg 3,16 Lincui Rd, Beijing 100101, Peoples R China 3.Tribhuvan Univ, Cent Dept Hydrol & Meteorol, Kathmandu, Nepal 4.Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China 5.CSIC, IPE, Avda Montanana 1005, E-50080 Zaragoza, Spain
Recommended Citation:
Wang, Yafeng,Sylvester, Steven Paul,Lu, Xiaoming,et al. The stability of spruce treelines on the eastern Tibetan Plateau over the last century is explained by pastoral disturbance[J]. FOREST ECOLOGY AND MANAGEMENT,2019-01-01,442:34-45