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Dynamic changes of habitats in China's typical national nature reserves on spatial and temporal scales

Journal of Geographical Sciences 2018年第6期28卷 778-790页

作者： ZHU Ping HUANG Lin XIAO Tong WANG Junbang Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Re-sources ResearchCASBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Satellite Environment Center Ministry of Environmental ProtectionBeijing 100094China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China

Until 2015,China had established 2740 nature reserves with a total area of 1.47million km^2,covering 14.8%of China’s terrestrial land *** on remote sensing inversion,ecological model simulation and spatial analysis methods,we analyzed the spatial and temporal variations of fractional vegetation coverage(FVC),net primary production(NPP),and human disturbance(HD)in habitats of typical national nature reserves(NNRs)during the first 15 years of the 21st century from 2000 to *** then the three indicators were compared between different NNR types and varied climate *** results showed that(1)the average 5-year FVC of NNRs increased from 36.3%to 37.1%,and it improved in all types of NNRs to some *** annual average FVC increased by 0.11%,0.84%,0.21%,0.09%,0.11%and 0.08%in NNRs of forest ecosystem,plain meadow,inland wetland,desert ecosystem,wild animal and wild plant,respectively.(2)The NPP annually increased by 2.06 g·m^(-2),1.23 g·m^(-2),0.28 g·m^(-2)and 0.4 g·m^(-2)in NNRs of plain meadow,inland wetland,desert ecosystem and wild animal,***,it decreased by 3.45 g·m^(-2)and2.35 g·m^(-2)in NNRs of forest ecosystem and wild plant respectively.(3)In the past 15 years,besides the slight decreases in the NNRs located at the Qinghai-Tibet Plateau and the south subtropical zone,HD enhanced in most of NNRs,especially HD in the warm temperate humid zone increased from 4.7%to 5.35%.

关键词： national nature reserves habitat fractional vegetation coverage net primary production humandisturbance

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Is Larger Scale Better? Evidence from Rice Farming in Jianghan Plain

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Journal of Resources and Ecology 2018年第4期9卷 352-364页

作者： WANG Jiayue XlN Liangjie Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Small-scale household agricultural production has been in conflict with China＇s agricultural *** the context of vigorously promoting rural land circulation and moderate scale management nationwide,research on the relationship between farm size and scale efficiency has become increasingly *** this paper,we use the ＂DEA-OLS＂ two stage method to analyze data from 368 surveys of rice farming households in the Jianghan *** scale efficiency of rice farming was calculated,and the relationship between farm size and scale efficiency *** results indicate that（1） the rice farm size is generally small in Jianghan Plain,with an average of 0.77 *** average scale efficiency is 0.88,and it is the main factor limiting an increase in comprehensive technical ***,88.32% of households are in the stage of increasing returns to scale.（2） There is a stable inverted ＂U＂ type relationship between rice farm size and scale *** characteristics of the householder,the household and land quality,the maximum scale efficiency corresponds to a household with 5 ha of rice farm.（3） Among householder characteristics,age has a significant negative influence on scale efficiency,and scale efficiency is lower for a household whose householder is engaged in non-farm work than for one whose householder is devoted to *** for land quality,there was a significant positive effect of irrigation on scale *** family characteristics,the application of a machine during the seeding process increased scale efficiency by 3.07%.Therefore,we suggest that local government should actively promote rural land circulation,implement a staged-scale management subsidy,and other forms of support for the purchase of agricultural machinery and technical *** investment in irrigation improvements and mechanical facilities and encouragement of farmers to enlarge their farm size could improve scale efficiency and farmin

关键词： Jianghan Plain rice farming farm size scale efficiency moderate scale management dataenvelopment analysis

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Research on the Sustainability of Afghanistan Based on the Emergy Analysis

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Journal of Resources and Ecology 2018年第5期9卷 508-515页

作者： JIN Lei LI Haitao YANG Jinfan Key Laboratory of Land Surface Pattern and Simulation institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Afghanistan is an important country for the Silk Road Economic Belt and the 21 st Century Maritime Silk Road（the Belt and Road） proposed by China. Due to years of war,Afghanistan is not well-developed economically. However,Afghanistan has abundant mineral resources and unique geographical advantages that are of far-reaching significance for Chinese economic strategic development. To investigate the sustainability of the eco-economic system of Afghanistan,we completed a quantitative evaluation of the emergy of Afghanistan during the period 2008 to 2015 by establishing an indicator system based on an emergy analysis. Results showed that from 2008 to 2015,the total emergy used of Afghanistan increased from 5.56×10^（22） sej to 9.75×10^（22） sej,among which the proportion of non-renewable emergy was less than 25.7%. This indicates that local resources in Afghanistan have yet to be exploited and utilized effectively and that its economic development relied heavily on the input of external resources. Meanwhile,the Emergy Sustainability Index（ESI） of Afghanistan from 2008 to 2015 dropped from 3.00 to 0.72,the Environmental Loading Ratio（ELR） increased from 0.77 to 2.06,and the Emergy Yield Ratio（EYR） dropped from 2.31 to 1.49,reflecting the imbalanced utilization of resources and the low level of economic development in Afghanistan. As a result,the potential for sustainable development of Afghanistan is relatively great. Basic infrastructure construction and reasonable exploitation of natural resources are the urgent needs.

关键词： emergy analysis sustainability Afghanistan the Belt and Road

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Wheat crop models underestimate drought stress in semi-arid and Mediterranean environments

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Field Crops Research 2025年 332卷

作者： H. Webber D. Cooke C. Wang S. Asseng P. Martre F. Ewert B. Kimball G. Hoogenboom S. Evett A. Chanzy S. Garrigues A. Olioso K.S. Copeland J.L. Steiner D. Cammarano Y. Chen M. Crépeau E. Diamantopoulos R. Ferrise L. Manceau J. White Leibniz Centre for Agricultural Landscape Research (ZALF) Müncheberg Germany Brandenburg University of Technology Cottbus Germany Digital Agriculture HEF World Agricultural Systems Center Technical University of Munich Freising Germany LEPSE Univ Montpellier INRAE Institut Agro Montpellier Montpellier France Crop Science Institute of Crop Science and Resource Conservation University of Bonn Bonn Germany US Arid-Land Agricultural Research Center USDA-ARS Maricopa USA Agricultural and Biological Engineering Dept. University of Florida Gainesville USA USDA ARS Conservation and Production Research Laboratory USDA-ARS Bushland USA UMR EMMAH INRAE Avignon Université Avignon France European Centre for Medium Range Weather Forecasts Shinfield Park Reading United Kingdom Unité de Recherche écologie des Forêts Méditerranéennes (URFM) INRAE Avignon France USDA ARS Conservation & Production Research Laboratory Bushland TX USA Agronomy Department Kansas State University Manhattan KS USA Department of Agroecology iClimate CBIO Aarhus University Tjele Denmark Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China College of Resources and Environment University of Chinese Academy of Sciences Beijing China Science and Technology Branch Agriculture and Agri-Food Canada Quebec City Quebec Canada University of Bayreuth Bayreuth Germany Department of Agri-food Production and Environmental Sciences (DISPAA) University of Florence Florence Italy

Under climate change and increasingly extreme weather, projections of water demand and drought stress from process-based crop models can inform risk management and adaptation strategies. Previous studies investigating maize crop models demonstrated considerable error in the simulation of water use, and no similar evaluation of wheat crop models exists. The aims of this study were to (1) evaluate wheat crop models’ performance in reproducing observed daily evapotranspiration (ET) for Mediterranean and semi-arid environments, and (2) identify factors and processes associated with model error and uncertainty. These were assessed with an ensemble of wheat crop models for two experiments, one conducted in Bushland, Texas, USA (three seasons, deficit and full irrigation) and another in Avignon, France (four rainfed seasons) with winter bread and durum wheat, respectively. Models were calibrated with all observed data for crop growth. The model ensemble median underestimated water use in all environments evaluated, suggesting a systematic bias. The relative error in underestimating daily ET was constant across levels of atmospheric evaporative demand; therefore, the absolute error was greater for days with larger evaporative demand. This implies errors in the soil water balance increase more rapidly under high evaporative demand conditions. Using a potential versus reference crop evapotranspiration approach did not explain relative model performance. However, the sensitivity analysis indicated that simulation of atmospheric evaporative demand terms explained much more uncertainty in seasonal water use than terms related to soil depth or root growth. Errors in simulated leaf area index were associated with errors in daily simulated ET, but the relationship varied with the growth stage. Collectively, the results suggest the need to improve simulation of atmospheric ET demand to avoid underestimating projected impacts of drought or required water resource availability for via

关键词： Crop models Evapotranspiration Wheat Drought stress Climate risk

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simulation on phosphorus release characteristics of Poyang Lake sediments under variable water levels and velocities

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Journal of Geographical Sciences 2017年第6期27卷 697-710页

作者： TONG Yali LIANG Tao WANG Lingqing LI Kexin Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China

Since the construction of the Three Gorges Dam, the Poyang Lake hydrological characteristics obviously changed. During the impoundment period of the Three Gorges Reservoir, the hydrodynamic factors of Poyang Lake varied. Water level dropped, the velocity decreased and water exchange time lengthened, which changed the release of phosphorous from sediments. In order to investigate how the hydrodynamic factors influence the release of phosphorous from sediments, we used a two-way annular flume device to simulate the release characteristics of phosphorous from sediments under variable water levels and velocities. We found that both water level rising and velocity increasing could enhance the distur- bance intensity to sediments, which caused the increase of suspended solids （SS） concentration, total phosphorus （TP） concentration in the overlying water, and the ability that phosphorus released to overlying water from sediments enhanced as well： when overlying water velocity maintained 0.3 m/s, SS concentration increased to 4035.85 mg/L at the water level 25 cm which was about 25 times compared to the minimum value and TP concentration in the overlying water also reached the maximum value at the water level 25 cm which was 1.2 times that of the value at 10 cm; when water level maintained 15 cm, SS concentration increased to 4363.35 mg/L at the velocity of 0.5 m/s which was about 28 times compared to the value of 0 m/s, and TP concentration in the overlying water increased from 0.11 mg/L to 0.44 mg/L. When the water level maintained 15 cm, the phosphorous release rate reached the maximum value of 4,86 mg/（md） at 0.4 m/s. The concentration of total dissolved phosphorous （TDP） and soluble reactive phosphate （SRP） both in overlying water and sediment-water interface were negatively correlated with pH. Using the parabolic equation, the optimum water level at a velocity of 0.3 m/s was calculated to be 0.57 cm, and the optimum velocity at water level of 15 cm was found to be 0.2

关键词： hydrodynamic factors sediment-water interface total phosphorous total dissolved phosphorous soluble reactive phosphate Poyang Lake

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Effects of an ecological conservation and restoration project in the Three-River Source Region, China

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Journal of Geographical Sciences 2017年第2期27卷 183-204页

作者： SHAO Quanqin CAO Wei FAN Jiangwen HUANG Lin XU Xinliang Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China

The first-stage of an ecological conservation and restoration project in the Three-River Source Region（TRSR）, China, has been in progress for eight years. However, because the ecological effects of this project remain unknown, decision making for future project implementation is hindered. Thus, in this study, we developed an index system to evaluate the effects of the ecological restoration project, by integrating field observations, remote sensing, and process-based models. Effects were assessed using trend analyses of ecosystem structures and services. Results showed positive trends in the TRSR since the beginning of the project, but not yet a return to the optima of the 1970 s. Specifically, while continued degradation in grassland has been initially contained, results are still far from the desired objective, ‘grassland coverage increasing by an average of 20%–40%＇. In contrast, wetlands and water bodies have generally been restored, while the water conservation and water supply capacity of watersheds have increased. Indeed, the volume of water conservation achieved in the project meets the objective of a 1.32 billion m^3 increase. The effects of ecological restoration inside project regions was more significant than outside, and, in addition to climate change projects, we concluded that the implementation of ecological conservation and restoration projects has substantially contributed to vegetation restoration. Nevertheless, the degradation of grasslands has not been fundamentally reversed, and to date the project has not prevented increasing soil erosion. In sum, the effects and challenges of this first-stage project highlight the necessity of continuous and long-term ecosystem conservation efforts in this region.

关键词： Three-River Source Region ecological conservation and restoration ecosystem monitoring and assessment ecological effects

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Corrigendum to “Overestimating Impacts of Urbanization on Regional Temperatures in Developing Megacity: Beijing as an Example”

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Advances in Meteorology 2020年第1期2020卷

作者： Wei Cao Lin Huang Lulu Liu Jun Zhai Dan Wu Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 *** School of Architecture and Civil Engineering Chengdu University Chengdu 610106 *** Satellite Environment Center Ministry of Ecology and Environment Beijing 100094 China Nanjing Institute of Environmental Sciences Ministry of Ecology and Environment Nanjing 210042 China

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Carbon Monitor, a near-real-time daily dataset of global CO2 emission from fossil fuel and cement production

arXiv

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arXiv 2020年

作者： Liu, Zhu Ciais, Philippe Deng, Zhu Davis, Steven J. Zheng, Bo Wang, Yilong Cui, Duo Zhu, Biqing Dou, Xinyu Ke, Piyu Sun, Taochun Guo, Rui Boucher, Olivier Bréon, François-Marie Lu, Chenxi Guo, Runtao Boucher, Eulalie Chevallier, Frederic Department of Earth System Science Tsinghua University Beijing100084 China Laboratoire des Sciences du Climate et de l'Environnement LSCE Orme de Merisiers Gif-sur-Yvette91191 France Department of Earth System Science University of California Irvine 3232 Croul Hall IrvineCA92697-3100 United States Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Depart ment of Electrical Engineering T singhua Universit y Beijing100084 China Institute Pierre-Simon Laplace Sorbonne Université / CNRS Paris France School of Mat hemat ical School T singhua Universit y Beijing100084 China Université Paris-Dauphine PSL Paris France

We constructed a near-real-time daily CO2 emission dataset, namely the Carbon Monitor, to monitor the variations of CO2 emissions from fossil fuel combustion and cement production since January 1st 2019 at national level with near-global coverage on a daily basis, with the potential to be frequently updated. Daily CO2 emissions are estimated from a diverse range of activity data, including: hourly to daily electrical power generation data of 29 countries, monthly production data and production indices of industry processes of 62 countries/regions, daily mobility data and mobility indices of road transportation of 416 cities worldwide. Individual flight location data and monthly data were utilised for aviation and maritime transportation sectors estimates. In addition, monthly fuel consumption data that corrected for daily air temperature of 206 countries were used for estimating the emissions from commercial and residential buildings. This Carbon Monitor dataset manifests the dynamic nature of CO2 emissions through daily, weekly and seasonal variations as influenced by workdays and holidays, as well as the unfolding impacts of the COVID-19 pandemic. The Carbon Monitor near-real-time CO2 emission dataset shows a 7.8% decline of CO2 emission globally from Jan 1st to Apr 30th in 2020 when compared with the same period in 2019, and detects a re-growth of CO2 emissions by late April which are mainly attributed to the recovery of economy activities in China and partial easing of lockdowns in other countries. Further, this daily updated CO2 emission dataset could offer a range of opportunities for related scientific research and policy making. Copyright © 2020, The Authors. All rights reserved.

关键词： Carbon

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Author Correction: A global moderate resolution dataset of gross primary production of vegetation for 2000-2016

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Scientific data 2021年第1期8卷 67页

作者： Yao Zhang Xiangming Xiao Xiaocui Wu Sha Zhou Geli Zhang Yuanwei Qin Jinwei Dong Center for Spatial Analysis Department for Microbiology and Plant Biology University of Oklahoma Norman OK 73019 USA. yaozhang@ou.edu. Center for Spatial Analysis Department for Microbiology and Plant Biology University of Oklahoma Norman OK 73019 USA. xiangming.xiao@ou.edu. Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering Institute of Biodiversity Science Fudan University Shanghai 200433 China. xiangming.xiao@ou.edu. Center for Spatial Analysis Department for Microbiology and Plant Biology University of Oklahoma Norman OK 73019 USA. State Key Laboratory of Hydroscience and Engineering Department of Hydraulic Engineering Tsinghua University Beijing 100084 China. Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China.

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Foliar carbon, nitrogen, and phosphorus stoichiometry in a grassland ecosystem along the Chinese Grassland Transect

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Acta Ecologica Sinica 2017年第3期37卷 133-139页

作者： Hailing, Yu Jiangwen, Fan Yuzhe, Li Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

Carbon (C), nitrogen (N), and phosphorus (P) are the basic nutrient elements required for plant growth and function. Ecological stoichiometry provides an important method for the determination of plant nutrient utilization and the environmental adaptation strategies of plants. Studying the stoichiometry of C, N and P is crucial to the understanding of nutrient cycling and ecosystem stabilization mechanisms. Most studies so far have focused only on N and P stoichiometry for plant leaves and ignored the stoichiometry characteristics among C, N, and P. As a major element of plant dry matter, C, along with critical nutrient elements (N and P) could regulate and influence the consumption and fixation of organic matter in ecosystems. Therefore, it is necessary to study the ecological stoichiometry of C, N, and P in plants. Here, C, N and P concentrations and their ratios were measured for 329 foliar samples collected at 132 sites along the 4500 km-long Chinese Grassland Transect (CGT) that traverses the Inner Mongolian and Qinghai-Tibet Plateaus. The content of C, N, and P of plant leaves in grassland ranged from 257.40 to 590.77 mg/g, 4.49 to 45.85 mg/g, and 0.20 to 3.40 mg/g, with an average of 463.76 mg/g, 19.94 mg/g, 1.31 mg/g, respectively. The coefficient of variation (CV) of P was highest (0.47) while the CV values of C and N were 0.09 and 0.34, respectively. N and P were positively correlated (R² = 0.491, P b 0.0001), in agreement with previous studies, while no significant correlation was found between C and P or between C and N. The ranges for C/N, N/P, and C/P were 10.93-93.67 (with an average of 26.86 and a CV value of 0.46) for C/N, 1.68-53.00 (with an average of 16.59 and a CV value of 0.39) for N/P, and 61.49-1995.24 (with an average of 436.77 and a CV value of 0.59) for C/P, respectively. The mass ratio of C:N:P in grassland plant was 440:17:1, and the atom ratio was 1136:43:1. C/N and C/P, C/N and N/P were positively correlated (R² =

关键词： C Chinese grassland Transect Ecological stoichiometry Grassland plant Leaf nutrients N P elements

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