| 1 | Variations in leaf characteristics of three species of angiosperms with changing of altitude in Qilian Mountains and their inland high-altitude pattern显示文摘In this study,39 leaf samples of three angiosperms(Betula albo-sinensis,tree species;and Caragana jubata and Berberis diaphana,shrub species) were collected in the middle-east parts at 2300–3640 m asl of the Qilian Mountains to study the variations of leaf characteristics of angiosperms with altitude change in inland high-altitude regions of China.Five leaf indexes,viz.epidermal cell density(ED),stomatal density(SD),stomatal index(SI),leaf vein density(VD) and carbon isotopic ratio(δ13C),were analyzed in laboratory.The results show that there are significant or even very significant linear correlations between the five indexes and altitude,of which SD,SI and VD exhibit a negative correlation with altitude,while ED and δ13C exhibit a positive correlation with altitude.Such a correlation assemblage is quite different from the situation in the low-altitude humid environment.Generally,only an assemblage of positive correlations can be observed between the indexes(viz.SD,SI and δ13C,etc.) and the altitude in the low-altitude humid environment,which were caused mainly by the plants' responses to the change of atmospheric CO2 concentration(Cα).However,an assemblage of the negative and positive correlations found here may be attributed mainly to the plants' responses to the change of physiological drought caused by change of low temperature,and here it is preliminarily called the inland high-altitude pattern of plant leaf variations. | WANG XueFang LI RuiYun LI XiaoZe MA FuJun SUN BaiNian WU JingYu WANG YouKui | 2014 | Science China Earth Sciences2014，57，4： | 8 |
| 4 | Ecological Environment Change in North Slope of Qilianshan Mountains显示文摘Based on meteorological,hydrological, forest,and grassland data collected by location observation,remote sensing,field surveys and relevant literature during 1956 to 2009,the ecological environment change in northern slope of the Qilianshan Mountains was analyzed synthetically using regression and correlation analyses.The results showed that the temperature had an annual variation rate of 0.033 4℃·a-1 in northern slope of the Qilianshan Mountains since 1960,and exhibited a raising trend,especially since 1987.The annual variation rate of annual precipitation was 0.570 2 mm·a-1,indicating that the precipitation tended to increase.The climate had changed from arid to humid in this region since 1976.From 1956 to 2006,the glacier area of six inland river basin(Shiyanghe river,Heihe river, Beidahe river,Shulehe river,Danghe river and Halternhe river) and Datonghe river basin in northern slope of Qilianshan mountains decreased by 17.7%. Thickness of the glacier reduced about 5-20 m,and the snow line rose about 100-140 m.The Glacier ice reserves in inland river basin of Hexi decreased by 11.4%.From 1972 to 2007,27 glaciers in the eastern section of the Qilianshan Mountains disappeared.From 1956 to 2009,the runoff change in the northern slope of the Qilianshan Mountains was different in different regions.The runoff was reduced significantly in Shiyanghe river basin, increased slightly in Heihe river basin,and increased obviously in Shulehe river basin.From 1958 to 1988, the area of deforestation and farming was more than 10.0 million ha,and the forest area was reduced 0.6 million ha.Since the Qilianshan Mountain Nature Reserve was established in 1989, the forest was restoring gradually because of continual protection and cultivating,and the forest area was increased 9.4 million ha from 1989 to 2008. Due to human interference,especially over-grazing impact,the quality of the wood-land,shrub-land and grass-land in northern slope of the Qilianshan Mountains were in a degraded condition,which resulted in serious harm of forest pests,decrease of shrubbery snow and water-retention capacity and exacerbation of soil erosion.The ecological environment in northern slope of the Qilianshan Mountains was improved in certain regions,but deteriorated in overall region,and the protection and management are needed to be strengthened. | Wang Youkui Jia Wenxiong Liu Chaohai Chen Wen Zhao Chengzhang Wang Qiyou Wang Jie | 2012 | Chinese Forestry Science and Technology2012，11，3： | 1 |
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