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Vegetation Pattern in Northern Tibet in Relation to Environmental and Geo-spatial Factors

Journal of Resources and Ecology 2018年第5期9卷 526-537页

作者： TIAN Li ZHANG Yangjian Claus HOLZAPFEL HUANG Ke CHEN Ning TAO Jian ZHU Juntao Lhasa Plateau Ecosystem Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences＋ Beijing 100101China Chinese Academy of Sciences Center for Excellence in Tibetan Plateau Earth Sciences Belling 100101＋ China Qianyanzhou Ecological Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101＋ China Department of Biological Sciences RutgersThe State University of New Jersey195 University AvenueNewark NJ 07102USA

Environmental and Geo-spatial factors have long been considered as crucial determinants of species composition and distributions. However,quantifying the relative contributions of these factors for the alpine ecosystems is lacking. The Tibetan Plateau has a unique ecological environment and vegetation types. Our objectives are to quantify the spatial distributions of plant communities on the Northern Tibetan Alpine grasslands and to explore the relationships between vegetation composition,Geo-spatial factors and environmental factors. We established 63 field plots along a 1200-km gradient on the Northern Tibetan Plateau Alpine Grassland and employed the two-way indicator species analysis（TWINSPAN） and the detrended canonical correspondence analysis（DCCA）. Fourteen communities of alpine grassland were identifiable along the transect and consisted of three vegetation types： Alpine meadow,Alpine steppe,and desert steppe. Vegetation composition and spatial distribution appeared to be largely determined by mean annual precipitation and less influenced by temperature. A large fraction（73.5%） of the variation in vegetation distribution was explained by environmental variables along this transect,somewhat less by Geo-spatial factors（56.3%）. The environmental and Geo-spatial factors explained 29.6% and 12.3% of the total variation,respectively,while their interaction explained 43.9%. Our findings provide strong empirical evidence for explaining biological and environmental synergetic relationships in Northern Tibet.

关键词： alpine grasslands environmental interpretation spatial pattern Tibetan Plateau vegetation composition

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Spatial pattern of plant species diversity and the influencing factors in a Gobi Desert within the Heihe River Basin, Northwest China

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Journal of Arid Land 2017年第3期9卷 379-393页

作者： ZHANG Pingping SHAO Ming'an ZHANG Xingchang Institute of Soil and Water Conservation Northwest A&F University State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water Resources Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

Understanding the spatial pattern of plant species diversity and the influencing factors has important implications for the conservation and management of ecosystem biodiversity. The transitional zone between biomes in desert ecosystems, however, has received little attention in that regard. In this study, we conducted a quantitative field survey （including 187 sampling plots） in a 40-km2 study area to determine the spatial pattern of plant species diversity and analyze the influencing factors in a Gobi Desert within the Heihe River Basin, Northwest China. A total of 42 plant species belonging to 16 families and 39 genera were recorded. Shrub and semi-shrub species generally represented the major part of the plant communities （covering 90% of the land surface）, while annual and perennial herbaceous species occupied a large proportion of the total recorded species （71%）. Patrick richness index （R）, Shannon-Wiener diversity index （H）, Simpson＇s dominance index （D）, and Pielou＇s evenness index （I） were all moderately spadaUy variable, and the variability increased with increasing sampling area. The semivariograms for R and H＇ were best fitted with Gaussian models while the semivariograms for D andJ were best fitted with exponential models. Nugget-to-still ratios indicated a moderate spatial autocorrelation for R, H＇, and D while a strong spatial autocorrelation was observed for J. The spatial patterns of R and H＇ were closely related to the geographic location within the study area, with lower values near the oasis and higher values near the mountains. However, there was an opposite trend for D. R, H＇, and D were significantly correlated with elevation, soil texture, bulk density, saturated hydraulic conductivity, and total porosity （P〈0.05）. Generally speaking, locations at higher elevations tended to have higher species richness and diversity and the higher elevations were characterized by higher values in sand and gravel contents, bulk density, and saturated hydraul

关键词： species diversity spatial heterogeneity environmental factors Gobi Desert transitional zone

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System-dynamics-based the analysis for material scheduling capacity

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IOP Conference Series: Earth and Environmental Science 2020年第1期608卷

作者： Han Jin Dai Er-fu Faculty of Geomatics Lanzhou Jiaotong University Lanzhou Gansu China Gansu Provincial Engineering Laboratory for National Geographic State Monitoring Lanzhou Gansu China National-Local Joint Engineering Research Center of Technologies and Applications for National Geographic State Monitoring Lanzhou Gansu China Lhasa Plateau Ecosystem Research Station Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research CAS Beijing China University of Chinese Academy of Sciences Beijing China

Emergency material scheduling is an essential part of disaster prevention and mitigation. This paper builds up materials scheduling model based on system dynamics, real-simulation the process of emergency material scheduling in disaster prevention and mitigation, exploring the main factors that affect a city's emergency capacity. The result shows that: the higher the scheduling capacity of government emergency material, the city's emergency capacity can reach its peak level faster. This model can predict materials scheduling speed in real-time and provide the government's emergency administrative department with a theoretical foundation to formulate reasonable disaster prevention and mitigation plans.

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Asymmetric Ridge–Furrow and Film Cover Improves Plant Morphological Traits and Light Utilization in Rain-Fed Maize

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Journal of Meteorological Research 2018年第5期32卷 829-838页

作者： Wanlin DONG Hang YU Lizhen ZHANG Ruonan WANG Qi WANG Qingwu XUE Zhihua PAN Zhigang SUN Xuebiao PAN Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Agricultural Meteorological Department College of Resources and Environmental SciencesChina Agricultural University China Meteorological Administration Training Centre Beijing 100081China College of Resources and Environment University of Chinese Academy of SciencesBeijing 1O0190China Wuchuan Scientific and Observing Experimental Station of Agro-Environment Ministry of Agriculture and Rural Affairs Hohhot 011700China Yushu Meteorological Service of Jilin Province Changchun 130061China Texas A&MAgriLife Research and Extension AmarilloTexas 79106-1769USA

Light is one of the most important natural resources for plant growth. Light interception （LI） and use efficiency （LUE） are often affected by the structure of canopy caused by growing pattern and agronomy managements. Agro-nomy practices, such as the ridge-furrow system and plastic film cover, might affect the leaf morphology and then light transmission within the canopy, thus change light extinction coefficient （k）, and LI and LUE. The objective of this study is to quantify LI and LUE in rain-fed maize （Zea Mays L.）, a major cropping system in Northeast China, under different combinations of ridge-furrow and film covering ratios. The tested ridge-furrow system （DRF：＂double ridges and furrows＂） was asymmetric and alternated with wide ridge （0.70 m in width and 0.15 m in height）, narrow furrow （0.10 m）, narrow ridge （0.40 m in width and 0.20 m in height）, and narrow furrow （0.10 m）. Field ex-periments were conducted in 2013 and 2014 in Jilin Province, Northeast China. Four treatments were tested： no ridges and plastic film cover （control, NRF）, ridges without film cover （DRF0）, ridges with 58% film cover （DRF58）, and ridges with 100% film cover （DRFl00）. DRF0 significantly increased LI by 9% compared with NRF, while film cover showed a marginal improvement. Specific leaf area in DRF experiments with film cover was significantly lower than in NRF, and leaf angle was 16% higher than in NRF, resulting in a 4% reduction in k. LUE of maize was not increased by DRF0, but was significantly enhanced by covering film in other DRF experiments, especially by 22% in DRF100. The increase of LUE by film cover was due to a greater biomass production and a lower assimilation portioning to vegetative organs, which caused a higher harvest index. The results could help farmers to optimize maize managements, especially in the region with decreased solar radiation under climate change.

关键词： light interception light use efficiency film mulching plant morphology ridge and furrow cultivation

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Impacts of nitrogen addition on nitrous oxide emission: Comparison of five nitrous oxide modules or algorithms

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Ecological Modelling 2020年 421卷

作者： Yujin Zhang Minna Ma Huajun Fang Dahe Qin Shulan Cheng Wenping Yuan State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Lanzhou Gansu 730000 China School of Atmospheric Sciences Sun Yat-Sen University Zhuhai Guangdong 519082 China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China College of Resources and Environment University of Chinese Academy of Sciences Beijing 100049 China

The contributions of long-lived nitrous oxide (N 2 O) to global climate and environment have received increasing attention. Especially, atmospheric nitrogen (N) deposition has substantially increased in recent decades due to the extensive use of fossil fuels in industry, which strongly stimulates the N 2 O emissions of terrestrial ecosystem. Several models have been developed to simulate the impacts of environmental factors on N 2 O emission from soil, but there are still large differences in the simulations of N 2 O emission and their responses to atmospheric deposition over global or regional scales. Using observations from N addition experiments in a subtropical forest, this study compared five widely-used N 2 O modules or algorithms (i.e. the N 2 O modules of DayCENT, PnET-N-DNDC and DyN, and the algorithm of NOE and NGAS) to investigate their performances for reproducing N 2 O emission, and especially the impacts of two forms of N additions (i.e. NH 4 + -N and NO 3 – -N, respectively) of two levels (low and high) on N 2 O emission. In general, the five modules reproduced the seasonal variations of N 2 O emission. Under the high levels of N addition compared to low ones for both NH 4 + -N and NO 3 – -N, however, not all modules can reproduce larger N 2 O emission. Relatively larger N 2 O emissions in measurements due to NH 4 + -N compared to NO 3 – -N additions were not indicated neither in all the modules. Moreover, there were substantial differences in simulating the ratios of N 2 O emission from nitrification and denitrification processes due to disagreements in the structure of these modules or algorithms. The comparison highlights the need to improve the representation of N 2 O production and diffusion processes. At the same time, it also highlights the application of WFPS in the model methodology as a key scheme that mediates the two microbial processes, i.e. nitrification and denitrification, could probably improve the performances of N 2 O models in futu

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Recovered Tibetan antelope at risk again

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SCIENCE 2019年第6462期366卷 194-194页

作者： Pei, Jie Wang, Li Xu, Wenjing Kurz, David J. Geng, Jing Fang, Huajun Guo, Xinlei Niu, Zheng Chinese Acad Sci Inst Remote Sensing & Digital Earth State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China Univ Calif Berkeley Dept Environm Sci Policy & Management Berkeley CA 94720 USA Chinese Acad Sci Inst Geog Sci & Nat Resources Res Key Lab Ecosystem Network Observat & Modeling Beijing 100101 Peoples R China

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Estimation of winter wheat yield using optimal vegetation indices from unmanned aerial vehicle remote sensing

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Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering 2018年第11期34卷 78-86页

作者： Zhu, Wanxue Li, Shiji Zhang, Xubo Li, Yang Sun, Zhigang Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academic of Science Beijing100101 China College of Resources and Environment University of Chinese Academy of Sciences Beijing100049 China Shandong Dongying Institute of Geographic Sciences Institute of Geographic Sciences and Natural Resources Research Chinese Academic of Science Dongying257000 China

Fast and accurate prediction of crop yield at field scale is an effective way to optimize agricultural management by government or local farmers for improving agriculture production. Compared with satellite remote sensing, unmanned aerial vehicle (UAV) remote sensing monitoring system has some advantages, such as obtaining images at high spatial resolution rapidly and cost-effectively, and flying under the clouds at low altitude. The complex equations and methods were commonly used to improve accuracy of yield prediction, but lacked quickness and simplicity. Thus, the object of this study was to: 1) Explore the optimal vegetation index (VI) and operation time to enhance the accuracy and quickness of yield prediction by wing-fixed UAV during wheat growing season. 2) Verify and improve the applicability of this method based on satellite remote sensing to UAV remote sensing research. The study was carried out 3 times i.e. from green to jointing stage, from the heading to filling stage, and the maturation stage during winter wheat growing season in 2016 in Binzhou City, which is in northwestern Shandong Province. In order to get stable winter wheat canopy multi-spectral datum, the cloudless and calm weather with better lighting conditions were selected to conduct the monitoring. Whiteboard data were collected before each monitoring event for later radiation correction. UAV remote sensing images with a spatial resolution of 0.16 m were generated after radiation correction, image mosaic and orthographical correction. In addition, 9 common vegetation indices (VIs) were calculated from green, red, red edge and near-infrared images, including EVI2 (enhanced vegetation index without a blue band), MSAVI2 (modified secondary soil adjusted vegetation index), OSAVI (optimized soil adjusted vegetation index), NDVI (normalized difference vegetation index), SAVI (soil adjusted vegetation index), MCARI (modified chlorophyll absorption ratio index), MTVI1 (modified triangular vegetati

关键词： Crops

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Spatial patterns and environmental factors influencing leaf carbon content in the forests and shrublands of China

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Journal of Geographical Sciences 2018年第6期28卷 791-801页

作者： ZHAO Hang XU Li WANG Qiufeng TIAN Jing TANG Xuli TANG Zhiyao XIE Zongqiang HE Nianpeng YU Guirui Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China South China Botanical Garden CASGuangzhou 510650China Department of Ecology College of Urban and Environmental SciencesPeking UniversityBeijing 100871China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyCASBeijing 100093China

Leaf carbon content(LCC)is widely used as an important parameter in estimating ecosystem carbon(C)storage,as well as for investigating the adaptation strategies of vegetation to their environment at a large *** this study,we used a dataset collected from forests(5119 plots)and shrublands(2564 plots)in China,*** plots were sampled following a consistent protocol,and we used the data to explore the spatial patterns of LCC at three scales:plot scale,eco-region scale(n=24),and eco-region scale(n=8).The average LCC of forests and shrublands combined was 45.3%,with the LCC of forests(45.5%)being slightly higher than that of shrublands(44.9%).Forest LCC ranged from 40.2%to 51.2%throughout the 24 eco-regions,while that of shrublands ranged from 35%to 50.1%.Forest LCC decreased with increasing latitude and longitude,whereas shrubland LCC de-creased with increasing latitude,but increased with increasing *** LCC increased,to some extent,with increasing temperature and *** results demonstrate the spatial patterns of LCC in the forests and shrublands at different scales based on field-measured data,providing a reference(or standard)for estimating carbon storage in vegetation at a regional scale.

关键词： carbon storage eco-regions foliar carbon shrubs stoichiometry China

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Effect of Water Level Fluctuations on Wintering Goose Abundance in Poyang Lake Wetlands of China

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Chinese Geographical Science 2017年第2期27卷 248-258页

作者： XIA Shaoxia LIU Yu CHEN Bin JIA Yifei ZHANG Huan LIU Guanhua YU Xiubo Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China The Second Surveying and Mapping Institute of Zhejiang Province Hangzhou 310012China Jiangxi Poyang Lake National Nature Reserve Authority Nanchang 330038China

The Poyang Lake is a Ramsar site and is the important over-wintering site for migratory waterbirds along the East Asian-Australasian Fly way. Examining the effects of water level fluctuations on waterbird abundance and analyzing the influencing mechanism is critical to waterbird protection in the context of hydrological alteration. In this study, the effect of water level regime on wintering goose abundance was examined and the influencing mechanism was interpreted. Synchronous waterbirds survey data, hydro- logical data, Moderate Resolution Imaging Spectroradiometer-Normalized Difference Vegetation Index （MODIS-NDVI） data and habi- tat data derived from Landsat TNUETM data and HJ/CCD data were combined. The satellite-derived Green Wave Index （GWI） based on MODIS-NDVI dataset was applied to detect changes in goose food resources. It was found that habitat size and vegetation conditions are key factors determining goose abundance. Geese numbers were positively correlated with habitat area, while intermediate range of vegetation productivity might benefit the goose abundance. Water level affects goose abundance by changing available habitat areas and vegetation conditions. We suggested that matching hydrological regime and exposed meadows time to wintering geese dynamics was crucial in the Poyang Lake wetlands. Our study could provide sound scientific information for hydrological management in the context of waterbird conservation.

关键词： water level fluctuation wintering geese Normalized Difference Vegetation Index （NDVI） Green Wave Index （GWI） waterbird habitat

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A Study of the Qianyanzhou Mode in a Subtropical Red Soil Hilly Region of China

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Journal of Resources and Ecology 2018年第6期9卷 653-662页

作者： ZOU Jingdong LIU Wenjing WANG Jingsheng WANG Tong LI Chao DING Lubin BAO Xiaoting Ji'an Institute of Agricultural Sciences Ji'anJiangxi 343103China School of Environment and Natural Resources Renmin University of China Beijing 100872China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Qianyanzhou is located in the heart of Jitai Basin in Guanxi town,the county seat of Taihe county in Jiangxi *** has a subtropical humid climate and exemplifies the geographic and geomorphologic characteristics of red soil hilly regions in southern *** the early 1980s,to control soil and water loss and problems with grain yields,Qianyanzhou's researchers proposed an innovative,comprehensive stereoscopic ag- riculture development mode known as the 'Qianyanzhou mode'.This mode included a forest-livestock-food ecosystem,a forest-fruit-economy ecosystem,and a land-water compound stereoscopic system,all located within a *** the Qianyanzhou mode,soil and water loss were completely controlled,thereby promoting environmental conservation and economic *** state and the society as a whole supported this mode thanks to its far-reaching social *** the 21st century,given new societal concerns and continuing economic development,Qianyanzhou mode has been restructured as two ecosystems of forest-fowl and planting-raising circular economies at landscape level,based on an increase in vegetation coverage from 4.3% to more than 80%.These improved modes can significantly enhance the ecosystem,reduce poverty,and to promote the construction of local ecological *** study introduces the Qianyanzhou mode and summarizes its characteristics in different *** hope that the information in this study supports improvements to and promotion of the Qianyanzhou *** believe the Qianyanzhou mode can play an important role in efforts to modify the agriculture industrial structure,alleviate poverty,and construct ecological civilization.

关键词： Qianyanzhou mode red soil hilly region compound management

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