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IEEE International Symposium on Geoscience and Remote Sensing (IGARSS)

作者： Junbang Wang Guangxin Lu Wei Cao Shaoqiang Wang Ouanqin Shao Guicai Li ArshadAli Shedayi Jiangwen Fan Key Laboratory of Ecosystem Network Observation and Modeling Chinese Academy of Science Beijing China Department of Grassland Science Qinghai University Xining China China Meteorological Administration National Satellite Meteorological Center Beijing China

The grass yield prediction is essential for the decision-making on grazing optimization and remotely sensed NDVI always used for the monitoring of the actual yield, but cannot for its prediction. The artificial neural networks (ANN) was applied to explore the early NDVI and climate data in winter-spring aiming to predict AGB as annual grass yield in the Three-Rivers Headwater Region. The predictor was assessed against the on-ground observations, which showed that the ANN had a better training and validating results with an R 2 of 0.75 and 0.84 respectively, but a lower test result of the R 2 of 0.31. However, the modelled AGB could well explain the observed values ( , and n=963), which indicated the ANN model had the good overall performance. This study provided a fundamental data for livestock management in early stage and the parameters optimization of ecosystem process model on the pixel scale.

关键词： Mathematical model Predictive models Meteorology Artificial neural networks Training Biological system modeling Data models

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Climatic Changes Dominant Interannual Trend in Net Primary Productivity of Alpine Vulnerable ecosystems

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Journal of Resources and Ecology 2019年第4期10卷 379-388页

作者： YANG Yihan WANG Junbang LIU Peng LU Guangxin LI Yingnian Key Lab of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101 China University of Chinese Academy of Sciehces Beijing 100049 China Henan Academy of Land and Resources Sciences Zhengzhou 450053 China Qinghai University Xining 810016 China Northwest Institute of Plateau Biology Chinese Academy of Sciences Xining 81000& China

The Three-River Headwaters(TRH), which is the source area of Yangtze River, Yellow River and Lancang River, is vulnerable and sensitive, and its alpine ecosystem is considered an important barrier for China’s ecological security. Understanding the impact of climate changes is essential for determining suitable measures for ecological environmental protection and restoration against the background of global climatic changes. However, different explanations of the interannual trends in complex alpine ecosystems have been proposed due to limited availability of reliable data and the uncertainty of the model itself. In this study, the remote sensing-process coupled model(GLOPEM-CEVSA) was used to estimate the net primary productivity(NPP) of vegetation in the TRH region from 2000 to 2012. The estimated NPP significantly and linearly correlated with the above-ground biomass sampled in the field(the multiple correlative coefficient R2 = 0.45, significant level P < 0.01) and showed better performance than the MODIS productivity product, i.e. MOD17 A3,(R2 = 0.21). The climate of TRH became warmer and wetter during 1990-2012, and the years 2000 to 2012 were warmer and wetter than the years1990–2000. Responding to the warmer and wetter climate, the NPP had an increasing trend of 13.7 g m^–2(10 yr)^–1 with a statistical confidence of 86%(P = 0.14). Among the three basins, the NPP of the Yellow River basin increased at the fastest rate of 17.44 g m^–2(10 yr)^–1(P = 0.158), followed by the Yangtze River basin, and the Lancang River, which was the slowest with a rate of 12.2 g m^–2(10 yr)^–1 and a statistical confidence level of only 67%. A multivariate linear regression with temperature and precipitation as the independent variables and NPP as the dependent variable at the pixel level was used to analyze the impacts of climatic changes on the trend of NPP. Both temperature and precipitation can explain the interannual variability of 83% in grassland NPP in the whole region, and

关键词： Three-River Headwaters alpine ecosystems net primary productivity climate changes

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Temporal and Spatial Distribution of Evapotranspiration and Its Influencing Factors on Qinghai-Tibet Plateau from 1982 to 2014

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Journal of Resources and Ecology 2019年第2期10卷 213-224页

作者： CUI Mingyue WANG Junbang WANG Shaoqiang YAN Hao LI Yingnian School of the Earth Sciences and Resources China University of Geosciences (Beijing) Beijing 100083 China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academyof Sciences Beijing 100101 China Northwest Institute of Plateau Biology Chinese Academy of Sciences Xining 810001 China School of Geography and Information Engineering China University of Geosciences (Beijing) Wuhan 430074 China National Meteorological Center China Meteorological Administration Beijing 100081 China

Evapotranspiration is the key driving factor of the earth’s water cycle, and an important component of surface water and energy balances. Therefore, it also reflects the geothermal regulation function of ecohydrological process. The Qinghai-Tibet Plateau is the birthplace of important rivers such as the Yangtze River and the Yellow River. The regional water balance is of great significance to regional ecological security. In this study, ARTS, a dualsource remote sensing evapotranspiration model developed on a global scale, is used to evaluate the actual evapotranspiration(ET) in the Qinghai-Tibet Plateau from 1982 to 2014, using meteorological data interpolated from observations, as well as FPAR and LAI data obtained by satellite remote sensing. The characteristics of seasonal. interannual and dynamic changes of evapotranspiration were analyzed. The rates at which meteorological factors contribute to evapotranspiration are calculated by sensitivity analysis and multiple linear regression analysis,and the dominant factors affecting the change of evapotranspiration in the Qinghai-Tibet Plateau are *** results show that:(1) The estimated values can explain more than 80% of the seasonal variation of the observed values(R^2 = 0.80, P < 0.001), which indicates that the model has a high accuracy.(2) The evapotranspiration in the whole year, spring, summer and autumn show significant increasing trends in the past 30 years, but have significant regional differences. Whether in the whole year or in summer, the southern Tibetan Valley shows a significant decreasing trend(more than 20 mm per 10 years), while the Ali, Lhasa Valley and Haibei areas show increasing trends(more than 10 mm per 10 years).(3) Sensitivity analysis and multiple linear regression analysis show that the main factor driving the interannual change trend is climate warming, followed by the non-significant increase of precipitation. However, vegetation change also has a considerable impact, and toge

关键词： evapotranspiration Qinghai-Tibet Plateau climatic factors spatial and temporal distribution

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Sources of uncertainty in exploring rangeland phenology： A case study in an alpine meadow on the central Tibetan Plateau

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Journal of Mountain Science 2017年第9期14卷 1827-1838页

作者： ZHAO Guang-shuai SHI Pei-li Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Science Beijing 100049 China China National Forestry Economics and Development Research Center Beijing 100714 China

Global climate change has been found to substantially influence the phenology of rangeland,especially on the Tibetan Plateau. However, there is considerable controversy about the trends and causes of rangeland phenology owing to different phenological exploration methods and lack of ground validation. Little is known about the uncertainty in the exploration accuracy of vegetation ***, in this study, we selected a typical alpine rangeland near Damxung national meteorological station as a case study on central Tibetan Plateau, and identified several important sources influencing phenology to better understand their effects on phenological exploration. We found man-made land use was not easily distinguished from natural rangelands, and therefore this may confound phenological response to climate change in the rangeland. Change trends of phenology explored by four methods were similar, but ratio threshold method(RTM) was more suitable for exploring vegetation phenology in terms of the beginning of growing season(BGS) and end of growing season(EGS). However, some adjustments are needed when RTM is used in extreme drought years. MODIS NDVI/EVI dataset was most suitable for exploring vegetation phenology of BGS and EGS. The discrimination capacities of vegetation phenology declined with decreasing resolution of remote sensing images from MODIS to GIMMS AVHRR datasets. Additionally, distinct trends of phenological change rates were indicated in different terrain conditions, with advance of growing season in high altitudes but delay of season in lower altitudes. Therefore, it was necessary to eliminate interference of complex terrain and man-made land use to ensure the representativeness of natural vegetation. Moreover, selecting the appropriate method to explore rangelands and fully considering the impact of topography are important to accurately analyze the effects of climate change on vegetation phenology.

关键词： Climate change Data quality NDVI Phenological exploration Northern Tibetan Plateau

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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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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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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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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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Correction to: Tussock microhabitats increase nitrogen uptake by plants in an alpine wetland

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Plant and Soil 2021年第1期469卷 527-527页

作者： Hu, Yi-Heng Zhang, Xiao-Ya Zhang, Kun Song, Ming-Hua Gao, Jun-Qin Dorodnikov, Maxim Soromotin, Andrey Kuzyakov, Yakov School of Ecology and Nature Conservation Beijing Forestry University Beijing China National Plateau Wetlands Research Center Southwest Forestry University Kunming China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Department of Soil Science of Temperate Ecosystems and Department of Agricultural Soil Science University of Göttingen Göttingen Germany Biogeochemistry of Agricultural Ecosystems University of Göttingen Göttingen Germany Tyumen State University Tyumen Russia Agro-Technological Institute RUDN University Moscow Russia

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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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