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| 1 | Effects of livestock exclusion and climate change on aboveground biomass accumulation in alpine pastures across the Northern Tibetan Plateau显示文摘To better understand the ecological and economic benefits of short-term grazing exclusion on the aboveground net primary productivity(ANPP)of alpine pastures,we conducted annual multi-site transect surveys in the summers from 2009 to 2011 and calculated the aboveground biomass discrepancy(ABD)between grazed and ungrazed pastures at plant community and economic group levels for three zonal alpine grassland types—meadow,steppe,and desert-steppe—across the northern Tibetan Plateau.Our results indicated that aboveground biomass(AGB)significantly differed among grassland types and declined northwesterly from 64.07 to11.44 g m-2with decreasing precipitation and increasing temperature.The mean ABD exhibited considerable community dependency,with meadow(12.47 g m-2)[steppe(6.91 g m-2)[desert steppe(2.54 g m-2),and it declined from 25.42 to 1.29 g m-2with decreasing precipitation and increasing temperature.‘Good forage’,i.e.grasses and sedges,benefited most from grazing exclusion,followed by edible forbs.With longer grazing exclusion durations(GEDs),the aboveground biomass of poisonous locoweeds initially decreased and then increased compared with the adjacent grazed sites.In the nested analysis of co-variances with a general linear model,growing season precipitation(GSP;from May to September)accounted for 52.67%ofthe observed variation in AGB,followed by AGT(9.77%)and pasture management systems(PMSs;grazing or grazing-excluded,5.31%).The variation in ABD was explained primarily by AGT(16.52%),GED(20.25%),and the interaction of AGT 9 GED(19.58%).Our results confirm that precipitation is the primary factor controlling the ANPP of alpine grasslands on the Northern Tibetan Plateau and that the ecological benefits arising from grazing exclusion are also partly dependent on grassland type and exclusion duration.Therefore,spatial and temporal variations in growing season precipitation and plant functional traits or economic group composition should be jointly considered when developing policies concerning the management and spatial layouts of grazing exclosures in this region. | Jianshuang Wu Xianzhou Zhang Zhenxi Shen Peili Shi Chengqun Yu Baoxiong Chen | 2014 | Chinese Science Bulletin2014，59，32： | 11 |
| 2 | Hydrochemical characteristics and element contents of natural waters in Tibet, China显示文摘六十件水样品( 35 件地下水样品, 22 件表面水样品和三件温泉的水样品)在拉萨城市里从村庄和镇在 36 个点被收集, Nagchu ( Nagqu )府,到 hydrochemical 特征和元素天赋满足的学习的在 2013 的府(西藏)浇的阿里( Ngari )府和 Shigatse ( Xigaze )。元素的集中在水样品并且与在从另外的区域的水样品的集中相比是坚定的,例如东南 Qinghai,南方 Xinjiang,东方四川和西方西藏。在不同区域的 hydrochemical 种类也被学习。在西藏的大多数部分的水到达中国国家标准和世界健康组织的要求国际标准。水样品的 pH 价值从 6.75 ~ 8.21 ,为吝啬的全部的溶解固体的价值是 225.54 mg/L。从阿里府的水里的砷的集中超过了中国国家标准和国际标准的限制,从 Shuanghu 的水里的氟化物的集中超过了中国国家标准和国际标准的限制。西藏的水里的主要 hydrochemical 种类是 Ca (HCO < 潜水艇 class= “ a-plus-plus ” > 3 ) 2 。从南方到向北,水里的主要阳离子从 Ca 变化<啜class=“ a-plus-plus ”>2+到 Na <啜class=“ a-plus-plus ”>+,而水里的主要阴离子从 HCO 变化<潜水艇class=“ a-plus-plus ”> 3 <啜class=“ a-plus-plus ”>到 Cl <啜class=“ a-plus-plus ”>并且那么<潜水艇class=“ a-plus-plus ”> 4 <啜class=“ a-plus-plus ”> 2 。河的化学从冰和雪浇并且融化水被在他们的来源在场的岩石统治,而地下水的化学被许多因素影响。构造部门决定水里并且也的主要元素的集中影响在场的 hydrochemical 种类。 | TIAN Yuan YU Chengqun LUO Kunli ZHA Xinjie WU Jianshuang ZHANG Xianzhou NI Runxiang | 2015 | Journal of Geographical Sciences2015，25，6： | 5 |
| 3 | Grazing alters environmental control mechanisms of evapotranspiration in an alpine meadow of the tibetan Plateau显示文摘Aims Evapotranspiration(Et)is an important component of the terrestrial water cycle and is easily affected by external disturbances,such as climate change and grazing.Identifying Et responses to grazing is instructive for determining grazing activity and informative for understanding the water cycle.Methods this study utilized 2 years(2014 and 2017)of eddy covariance data to test how grazing regulated Et for an alpine meadow ecosystem on the tibetan Plateau(tP)by path analysis.Important Findings Radiation dominated Et with a decision coefficient of 64-74%.the soil water content(SWc)worked as the limiting factor in the fenced site.However,in the grazing site,the limiting factor was the vapor pressure deficit(VPD).Grazing had large effects on Et because it greatly affected the water conditions.the SWc and VPD were enhanced by 14.63%and 4.36%in the grazing site,respectively.therefore,sufficient water was supplied to Et,especially during drought,and strengthened the transpiration pull.As a result,a favorable micrometeorological environment was created for Et.Grazing shifted the limiting factor of Et from the SWc to VPD,which weakened the limiting effect of the water conditions on Et and advanced the Et peak time.In addition,grazing altered the compositions of Et by changing the community structure,which directly resulted in an increased Et.In summary,grazing enhanced Et through altering the community structure and micrometeorological environments.the findings of this study further improve our understanding of the driving mechanisms of grazing on Et and will improve our predictions for the global water cycle. | Tingting An Mingjie Xu Tao Zhang Chengqun Yu Yingge Li Ning Chen Jiaxing Zu Junxiang Li Juntao Zhu Yi Sun Tingting Zhao Guirui Yu | 2019 | Journal of Plant Ecology2019，12，5： | 3 |
| 4 | Effect of inclusion of grasses and wet hulless-barley distillers' grains on the fermenta- tion and nutritive quality of oat straw-and straw-grass silages in Tibet显示文摘 | Yuan Xianjun Yu Chengqun Li ZhiHua | 2013 | Animal Production Science2013，53，5： | 1 |
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