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| 1 | The spatial pattern of grassland aboveground biomass on Xizang Plateau and its climatic controls显示文摘Aims Grassland is the most widely distributed vegetation type on the Xizang Plateau.Accurate remote sensing estimation of the grass-land aboveground biomass(AGB)in this region is influenced by the types of vegetation indexes(VIs)used,the grain size(resolution)of the remote sensing data and the targeted ecosystem features.This study attempts to answer the following questions:(i)Which VI can most accurately reflect the grassland AGB distribution on the Xizang Plateau?(ii)How does the grain size of remote sensing imagery affect AGB reflection?(iii)What is the spatial distribution pattern of the grassland AGB on the plateau and its relationship with the climate?Methods We investigated 90 sample sites and measured site-specific AGBs using the harvest method for three grassland types(alpine meadow,alpine steppe and desert steppe).For each sample site,four VIs,namely,Normalized Difference VI(NDVI),Enhanced VI,Normalized Difference Water Index(NDWI)and Modified Soil-Adjusted VI(MSAVI)were extracted from the Moderate Resolution Imaging Spectroradiometer(MODIS)products with grain sizes of 250 m and 1 km.Linear regression models were employed to iden-tify the best estimator of the AGB for the entire grassland and the three individual grassland types.Paired Wilcoxon tests were applied to assess the grain size effect on the AGB estimation.General linear models were used to quantify the relationships between the spatial distribution of the grassland AGB and climatic factors.Important Findings The results showed that the best estimator for the entire grass-land AGB on the Xizang Plateau was MSAVI at a 250 m grain size(MSAVI_(250 m)).For each individual grassland type,the best estimator was MSAVI at a grain size of 250 m for alpine meadow,NDWI at a grain size of 1 km for alpine steppe and NDVI at a grain size of 1 km for desert steppe.The explanation ability of each VI for the grassland AGB did not significantly differ for the two grain sizes.Based on the best fit model(AGB=−10.80+139.13 MSAVI_(250 m)),the spatial pattern of the grassland AGB on the plateau was characterized.The AGB varied from 1 to 136 g m^(−2).Approximately 59%of total spatial variation in the AGB for the entire grassland was explained by the combination of the mean annual precipitation(MAP)and mean annual temperature.The explanatory power of MAP was weaker for each individual grassland type than that for the entire grassland.This study illustrated the high efficiency of the VIs derived from MODIS data in the grassland AGB estimation on the Xizang Plateau due to the vegetation homogeneity within a 1×1 km pixel in this region.Furthermore,MAP is a primary driver on the spatial variation of AGB at a regional scale. | Yanbin Jiang Jian Tao Yongqi Huang Juntao Zhu Li Tian Yangjian Zhang | 2015 | Journal of Plant Ecology2015，8，1： | 6 |
| 2 | Late Mesozoic rifting and its deep dynamic mechanisms in the central Sulu orogenic belt: Records from Lingshan Island显示文摘The Lingshan Island scientific drill confirms that two episodes(Laiyang period and Qingshan period) of rifting developed in the central Sulu orogenic belt(SOB) in Late Mesozoic. With a set of methods including fieldwork, drilling, core logging, zircon U-Pb dating and whole rock geochemistry applied, the age, the depositional sequence and the deep dynamic mechanisms of rift evolution were unraveled. The stratigraphic sequence of the Laiyang-Qingshan Groups on Lingshan Island was composed of two different rifting sequences:(1) Laiyang Group(147–125 Ma), which consists of deep-water gravity flow deposits with interlayers of intermediate volcanic rocks;and(2) Lower Qingshan Group(125–119 Ma), which unconformably overlies the former sequence and contains subaerial volcanic deposits and terrestrial deposits. The tectonic environment changed during the evolution of these two episodes of rifting: the rift was in a NNW-SSE extensional environment in the Laiyang period and showed the typical passive rifting character that “lithospheric extension and rifting preceded volcanism”. The passive rifting period was ended by a short WNW-ESE compression at about 125 Ma. After that, the tectonic environment transferred to a strong NW-SE extensional environment and the rifting evolved into a volcanic arc basin in the Qingshan period. The igneous rocks are shoshonitic to high-K calc-alkaline trachyandesites to trachytes with a few intercalated lamprophyres and a rhyolite.The geochemical characteristics of the igneous rocks indicate that they are mantle-derived melts with a metasomatized mantle source and/or crustal contamination. In addition, an increased thinning of the lithosphere happened during the rifting episodes.The low-angle subduction of the Paleo-Pacific plate in the Jurassic weakened the thickened SOB lithospheric mantle. The rollback of the subducting plate started in late Jurassic to early Cretaceous, and the SOB lithospheric mantle was delaminated synchronously because of the gravity collapse. Thus, this caused passive rifting in the Laiyang period. Thereafter, the rollback and trench retreat of the high-angle subducting Paleo-Pacific plate would have achieved its climax, resulting in the strong regional extension. Passive rifting was ended by the crustal uplift caused by asthenospheric upwelling beneath the rift. The lower crust was heated by the upwelling asthenosphere and partially melted to form felsic melts, which were emplaced upwards and erupted explosively. The rift evolved into a volcanic arc basin in the Qingshan period and showed some characteristics of active rifting. Above all, a passive rifting in the Laiyang period and a volcanic arc basin in the Qingshan period developed successively in the Lingshan Island area(the central SOB). This records the transfer of the study area from the Paleo-Tethys tectonic domain to the circum-Pacific tectonic domain. The delamination of SOB lithospheric mantle and the upwelling of asthenospheric material were the deep dynamic mechanisms driving the development and evolution of two rift episodes. Additionally, the rift development was controlled remotely by the subduction of the Paleo-Pacific plate. | Tengfei ZHOU Yaoqi ZHOU Nina SФAGER Paul Martin HOLM Zhenkai ZHANG Jun WANG Zhao LIANG Hongyu MU Yanjun CHENG Feifei LIU Miao WANG Yue ZHANG Hui ZHANG Yangjian GU Shihui DONG Hanjie ZHAO Manjie LI Yang CHEN Yanzi LIU | 2022 | Science China Earth Sciences2022，65，9： | 3 |
| 3 | Two Ultraviolet Radiation Datasets that Cover China显示文摘Ultraviolet(UV) radiation has significant effects on ecosystems, environments, and human health, as well as atmospheric processes and climate change. Two ultraviolet radiation datasets are described in this paper. One contains hourly observations of UV radiation measured at 40 Chinese Ecosystem Research Network stations from 2005 to 2015. CUV3 broadband radiometers were used to observe the UV radiation, with an accuracy of 5%, which meets the World Meteorology Organization's measurement standards. The extremum method was used to control the quality of the measured datasets. The other dataset contains daily cumulative UV radiation estimates that were calculated using an all-sky estimation model combined with a hybrid model. The reconstructed daily UV radiation data span from 1961 to 2014. The mean absolute bias error and root-mean-square error are smaller than 30% at most stations, and most of the mean bias error values are negative, which indicates underestimation of the UV radiation intensity. These datasets can improve our basic knowledge of the spatial and temporal variations in UV radiation. Additionally, these datasets can be used in studies of potential ozone formation and atmospheric oxidation, as well as simulations of ecological processes. | Hui LIU Bo HU Yuesi WANG Guangren LIU Liqin TANG Dongsheng JI Yongfei BAI Weikai BAO Xin CHEN Yunming CHEN Weixin DING Xiaozeng HAN Fei HE Hui HUANG Zhenying HUANG Xinrong LI Yan LI Wenzhao LIU Luxiang LIN Zhu OUYANG Boqiang QIN Weijun SHEN Yanjun SHEN Hongxin SU Changchun SONG Bo SUN Song SUN Anzhi WANG Genxu WANG Huimin WANG Silong WANG Youshao WANG Wenxue WEI Ping XIE Zongqiang XIE Xiaoyuan YAN Fanjiang ZENG Fawei ZHANG Yangjian ZHANG Yiping ZHANG Chengyi ZHAO Wenzhi ZHAO Xueyong ZHAO Guoyi ZHOU Bo ZHU | 2017 | Advances in Atmospheric Sciences2017，34，7： | 2 |
| 4 | Forming of A New Liquid Crystalline through Hydrogen Bonding显示文摘A stable S. phase is formed through hydrogen bonding between side-chain aromatic acid groups ofpolysiloxane;Bending of polysiloxane with N-Acetyl Latimic acid (NAA) gives a chiraI S: phase; The influ-ence of polymerism aud hydrogen bond inductlon effect over mesophase is discussed. The influence of NAAover mesophase is studied. | Hu Yangjian, Huang Ronghua, Zhang Xianliang’(College of Chemistry, Wuhan University,Wuhan 430072,China) | 1998 | Wuhan University Journal of Natural Sciences1998，3，2： | 2 |
| 5 | A test of the latitu-dinal defense hypothesis:herbivory,tannins and total phenolics in four North American tree species显示文摘 | Adams J M Rehill B Zhang Yangjian | | 0，，3： | 1 |
| 6 | Green-up dates in the Tibetan Plateau have continuously advanced from 1982 to 2011显示文摘 | Zhang Geli Zhang Yangjian Dong Jinwei | 2013 | Proc Natl Acad Sci USA2013，110，11： | 1 |
| 7 | Two-dimensional PCA: a new approach to appearance based face representation and recognition显示文摘 | YangJian Zhang D Frangi A F | 2004 | IEEE Transactions on Pattern Analysis and Machine Intelligence2004，26，1： | 1 |
| 8 | Species turnover drives grassland community to phylogenetic clustering over long-term grazing disturbance显示文摘放牧通过改变草地群落物种组成和生物多样性,进而影响草地群落结构,对草地生态系统服务和功能产生深远的影响。然而,有关系统发育多样性和系统发育群落结构对长期放牧干扰的响应和适应的研究仍然很少,尤其是对于分布在极端环境中的生态系统。我们在青藏高原高寒草地上开展了多放牧强度的试验,探讨放牧干扰对植物系统发育多样性和群落结构的影响。研究发现,放牧干扰增加了植物群落的物种丰富度,促进了群落物种周转,从而改变了群落物种组成。低强度放牧对系统发育多样性和群落结构没有显著影响,而高强度放牧促使群落结构由分散向聚集变化。高强度放牧通过强烈的环境过滤作用,选择了一些耐牧的草地植物物种。在高强度放牧条件下,草地群落的聚集结构由近缘种的入侵和远缘种的丢失共同驱动。在植物功能性状水平上,我们发现与低强度放牧相比,高强度放牧通过改变根系深度对物种入侵产生影响,在很大程度上提升了物种的入侵性。我们的研究强调,仅仅利用物种丰富度和多样性并不能全面反映放牧干扰对草地群落的影响,而且在以后的放牧生态学研究中应该更加关注物种周转对群落系统发育多样性和群落结构的影响。 | Juntao Zhu Yangjian Zhang Wenfeng Wang Xian Yang Ning Chen Ruonan Shen Li Wang Lin Jiang | 2020 | Journal of Plant Ecology2020，13，2： | 1 |
| 9 | Elevation-dependent temperature change in the Qinghai–Xizang Plateau grassland during the past decade显示文摘 | Jian Tao Yangjian Zhang Juntao Zhu Yanbin Jiang Xianzhou Zhang Tao Zhang Yi Xi | 2014 | Theoretical and Applied Climatology (-)2014，，1： | 1 |
| 10 | Sustainable wildlife protection on the Qingzang Plateau显示文摘Besides its ecological services to China and even Asia,the Qingzang Plateau(QP)hosts a rich variety of wildlife species.During the last century,wildlife population decreased quickly on the QP,driven by human interventions.Recently,wildlife has witnessed rapid recovery mainly propelled by a series of wildlife conservation policies.However,some cautions merit attentions to sustain wildlife restoration and conservation on the QP.This paper casted an overview of environmental and social-economic changes on the QP affecting wildlife subsistence.Re-sults show that QP has been warming,which can benefit wildlife recovery by easing extreme low temperature stresses.The fast growing social economy across the QP lays a solid economic foundation for investing on wildlife protection.Measures such as establishing conservation areas,constructing wildlife pathway corridors,and en-couraging herdsman moving out from wildlife rich regions,have boosted wildlife recovery.However,wildlife recovery is constrained by the limited carrying capacity of the ecosystem,left by domestic livestock.Additionally,fences intended to delineate conservation areas or to separate each type of grassland use,have brought about profound side effects on wildlife through fragmentation of their habitats.It is recommended to set up the fence in a more ecological way,which can be achieved by bypassing the wildlife frequent pathway and using mate-rials devoid of steel barb.Only considering both opportunities and problems simultaneously,can the wildlife protection on the QP be sustained. | Yangjian Zhang Ran Zhao Yaojie Liu Ke Huang Juntao Zhu | 2021 | Geography and Sustainability2021，2，1： | 1 |
| 11 | The Importance of Differentiating Urban and Rural Phenomena in Examining the Unequal Distribution of Locally Desirable Land显示文摘 | Zhang Yangjian Tarrant M Green G | 2008 | Journal of Environmental Management2008，88，： | 1 |
| 12 | Lagged climatic effects on carbon fluxes over three grassland ecosystems in China显示文摘Aims The plasticity of ecosystem responses could buffer and post-pone the effects of climates on ecosystem carbon fluxes,but this lagged effect is often ignored.In this study,we used carbon flux data collected from three typical grassland ecosystems in China,including a temperate semiarid steppe in Inner mongolia(Neimeng site,Nm),an alpine shrub-meadow in Qinghai(Haibei site,Hb)and an alpine meadow steppe in Tibet(Dangxiong site,DX),to examine the time lagged effects of environmental factors on CO_(2) exchange.Methods Eddy covariance data were collected from three typical Chinese grasslands.In linking carbon fluxes with climatic factors,we used their averages or cumulative values within each 12-month period and we called them‘yearly’statistics in this study.To investigate the lagged effects of the climatic factors on the car-bon fluxes,the climatic‘yearly’statistics were kept still and the‘yearly’statistics of the carbon fluxes were shifted backward 1 month at a time.Important Findingssoil moisture and precipitation was the main factor driving the annual variations of carbon fluxes at the alpine Hb and DX,respectively,while the Nm site was under a synthetic impact of each climatic factor.The time lagged effect analysis showed that temperature had several months,even half a year lag effects on Co2 exchange at the three studied sites,while moisture’s effects were mostly exhibited as an immediate manner,except at Nm.In general,the lagged climatic effects were relatively weak for the alpine ecosystem.our results implied that it might be months or even 1 year before the variations of ecosystem carbon fluxes are adjusted to the current climate,so such lag effects could be resistant to more frequent climate extremes and should be a critical component to be considered in evaluating ecosystem stability.an improved knowledge on the lag effects could advance our understanding on the driving mechanisms of climate change effects on ecosystem carbon fluxes. | Tao Zhang Mingjie Xu Yi Xi Juntao Zhu Li Tian Xianzhou Zhang Yanfen Wang Yingnian Li Peili Shi Guirui Yu Xiaomin Sun Yangjian Zhang | 2015 | Journal of Plant Ecology2015，8，3： | 1 |
| 13 | Moving toward a new era of ecosystem science显示文摘Ecosystem is a fundamental organizational unit of the biosphere in which biological communities interact with their non-biological environment through energy flows and material cycles.Ecosystem science is the study of patterns,processes,and services of ecosystems.Since the 1990s,rising concerns regarding global climate change,biodiversity loss,ecosystem degradation,and sustainability of the human-dominated biosphere have stimulated the growth of ecosystem science,which is expected to provide systematic solutions to many of these major issues facing human societies.This paper provides a comprehensive review of the current progress in ecosystem science and identifies some key research challenges facing this discipline.We demonstrate that a key feature of the current progress in ecosystem science is its evolution from primarily theoretical explorations toward more systematic,integrative and application-oriented studies.Specifically,five major changes in the discipline over the past several decades can be identified.These include:(1)the expansion of the primary goal from understanding nature to include human activities;(2)the broadening of the research focus from single ecosystem types to macro-ecosystems comprising multiple regional ecosystems;(3)the shifting of research methods from small-scale observations and experiments to large-scale observations,network experiments,and model simulations;(4)the increasing attention to comprehensive integration of ecosystem components,processes,and scales;and(5)the shifting from a primarily biology-oriented focus to an integrated multi-disciplinary scientific field.While ecosystem science still faces many challenges in the future,these directional changes,along with the rapidly enriched research tools and data acquisition capabilities,lay a promising ground for the discipline’s future as a fundamental scientific basis for solving many environmental challenges facing human societies. | Guirui Yu Shilong Piao Yangjian Zhang Lingli Liu Jian Peng Shuli Niu | 2021 | Geography and Sustainability2021，2，3： | 1 |
| 14 | Response of microbial biomass to grazing in an alpine meadow along an elevation gradient on the Tibetan Plateau显示文摘 | Gang Fu Zhenxi Shen Xianzhou Zhang Yuting Zhou Yangjian Zhang | 2012 | European Journal of Soil Biology2012，，： | 1 |
| 15 | Recent progress in electrospun nanofibers and their applications in heavy metal wastewater treatment显示文摘Novel adsorbents with a simple preparation process and large capacity for removing highly toxic and nondegradable heavy metals from water have drawn the attention of researchers.Electrospun nanofiber membranes usually have the advantages of large specific surface areas and high porosity and allowing flexible control and easy functionalization.These membranes show remarkable application potential in the field of heavy metal wastewater treatment.In this paper,the electrospinning technologies,process types,and the structures and types of nanofibers that can be prepared are reviewed,and the relationships among process,structure and properties are discussed.On one hand,based on the different components of electrospun nanofibers,the use of organic,inorganic and organic−inorganic nanofiber membrane adsorbents in heavy metal wastewater treatment are introduced,and their advantages and future development are summarized and prospected.On the other hand,based on the microstructure and overall structure of the nanofiber membrane,the recent progresses of electrospun functional membranes for heavy metal removal are reviewed,and the advantages of different structures for applications are concluded.Overall,this study lays the foundation for future research aiming to provide more novel structured adsorbents. | Xizi Xu He Lv Mingxin Zhang Menglong Wang Yangjian Zhou Yanan Liu Deng-Guang Yu | 2023 | Frontiers of Chemical Science and Engineering2023，17，3： | 1 |
| 16 | Green-up dates in the Tibetan Plateau have continuously advanced from 1982 to 2011显示文摘 | Zhang Geli Zhang Yangjian Dong Jinwei | 2013 | Proceedings of the National Academy of Sciences of the United States of America (PNAS)2013，110，11： | 1 |
| 17 | Estimating air temperature of an alpine meadow on the Northern Tibetan Plateau using MODIS land surface temperature显示文摘 | Gang Fu Zhenxi Shen Xianzhou Zhang Peili Shi Yangjian Zhang Jianshuang Wu | 2010 | Acta Ecologica Sinica2010，，1： | 1 |
| 18 | Current status and future directions of the Tibetan Plateau ecosystem research显示文摘The Tibetan Plateau (TP) encompasses Xizang and Qinghai and parts of northern Yunnan and Sichuan provinces, with a total area of circa 2.6 millions km2. The 2013 satellite data showed that grasslands, forests, wetlands, agricultural lands, and deserts account for 60%, 7.7%, 1.4%, 0.3%, and 30%, respectively, of total TP land (1)Due to its existence in dry, high altitude and cold environments, the TP ecosystem is extremely vulnerable to global climate change and studies on the TP ecosystem can be utilized as a pre-warning for other ecosystems. | Yangjian Zhang Yixuan Zhu Junxiang Li Yao Chen | 2019 | Science Bulletin2019，64，7： | 1 |
| 19 | Review on global change status and its impacts on the Tibetan Plateau environment显示文摘The Tibetan Plateau(TP)holds fundamental ecological and environmental significances to China and Asia.The TP also lies in the core zone of the belt and road initiative.To protect the TP environment,a comprehensive screening on current ecological research status is entailed.The teased out research gap can also be utilized as guidelines for the recently launched major research programs,i.e.the second TP scientific expedition and silk and belt road research plan.The findings showed that the TP has experienced significant temperature increase at a rate of 0.2℃ per decade since 1960s.The most robust warming trend was found in the northern plateau.Precipitation also exhibited an increasing trend but with high spatial heterogeneity.Changing climates have caused a series of environmental consequences,including lake area changes,glacier shrinkage,permafrost degradation and exacerbated desertification.The rising temperature is the main reason behind the glaciers shrinkage,snow melting,permafrost degradation and lake area changes on the TP and neighboring regions.The projected loss of glacial area on the plateau is estimated to be around 43%by 2070 and 75%by the end of the century.Vegetation was responsive to the changed environments,varied climates and intensified human activities by changing phenology and productivity.Future global change study should be more oriented toward integrating various research methods and tools,and synthesizing diverse subjects of water,vegetation,atmosphere and soil. | Aamir Latif Sana Ilyas Yangjian Zhang Yuqin Xin Lin Zhou Quan Zhou | 2019 | Journal of Plant Ecology2019，12，6： | 1 |
| 20 | Coherent and partially coherent dark hollow beams with rectangular symmetry and paraxial propagation properties显示文摘 | Cai Yangjian Zhang Lei | 2006 | Journal of the Optical Society of America B2006，23，7： | 1 |
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