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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

Assessing productivity and carbon sequestration capacity of subtropical coniferous plantations using the process model PnET-CN

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Journal of Geographical Sciences 2011年第3期21卷 458-474页

作者： YAN Yuan wang shaoqiang wang Yidong WU Weixing wang Jingyuan CHEN Bin YANG Fengting Key Laboratory of Ecosystem Network Observation and Modeling (KLENOM) Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100039 China School of Geography and Earth Sciences McMaster University Hamilton ON Canada Qianyanzhou Ecological Experimental Station KLENOM Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China

A generalized, lumped-parameter ecological model PnET-CN was calibrated and validated for a subtropical coniferous plantation in southern China. PnET-CN model describes the biogeochemical cycles of carbon （C） and nitrogen （N） and can assist in estimating carbon sequestration potential. For validation of PnET-CN, data from coniferous forest plantations in southern China was used. Simulated daily gross primary productivity （GPP） from 2005 to 2007 agreed well with observations （R2=0.56, S.D.=0.009）. Simulations of monthly soil respiration （Rs） from 2005-2007 agreed well with Rs observations （R2=0.67, S.D. =0.03）. Simu- lated annual net primary productivity （NPP） from 1998-2006 was 803＋33 gCm 2a-1, about 4% higher than NPP observation （752＋51 gCm-2a-1）. Simulations of annual NEP from 2005-2007 only overestimate 9 gCm-2a-1 （4%）, 4 gCm 2a-1 （1%） and 34 gCm 2a-1 （8%） compared to NEP observations, respectively. Simulated annual foliar N concentration （FolNCon）（1.09%） is 10% lower than observed monthly FolNCon （0.87%-1.58%）. Simulated annual N leaching （0.26 gNm-2） is about 10% lower than leaching observation （0.29 gNm-2）. PnET-CN model validation indicates that PnET-CN is capable to simulate daily GPP, annual NPP, annual NEP, monthly Rs, annual FolNCon and annual nitrate N leaching for subtropical coniferous planta- tions in southern China. The results obtained from the validation test revealed that PnET-CN model can be used to simulate carbon sequestration of planted coniferous forests in southern China to a high level of precision. Sensitivity analysis suggests that great care should be taken in developing generalizations as to how forests will respond to a changing climate. PnET-CN performed satisfactorily in comparison to other models that have already been calibrated and validated in coniferous planted subtropical forests in China. Based on PnET-CN validation and its comparison to other models, future improvement of PnET-CN should focus on seasonal foliar N dynamics a

关键词： coniferous plantations PnET-CN Model validation foliar N concentration C sequestration

Guest-Mediated Hierarchical Self-Assembly of Dissymmetric Organic Cages to Form Supramolecular Ferroelectrics Guest-Mediated Hierarchical Self-Assembly of Dissymmetric Organic Cages to Form Supramolecular Ferroelectrics

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CCS Chemistry 2022年第7期4卷 2420-2428页

作者： Xiaoning Liu Gucheng Zhu Dan He Lehua Gu Peiyue Shen Guijia Cui shaoqiang wang Zhiwen Shi Daigo Miyajima Shiyong wang Shaodong Zhang Frontiers Science Center for Transformative Molecules Shanghai Key Laboratory of Electrical Insulation and Thermal AgingSchool of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240 Key Laboratory of Artificial Structures and Quantum Control(Ministry of Education) Shenyang National Laboratory for Materials ScienceSchool of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240 RIKEN Center for Emergent Matter Science WakoSaitama 351-0198 State Key Laboratory of Surface Physics Key Laboratory of Micro and Nano Photonic Structures(MOE)Department of PhysicsFudan UniversityShanghai 200438 Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240

Herein,we report on the guest-responsive hierarchical self-assembly of dissymmetric cage DC-1 with an intrinsic dipole along its C_(3)-symmetric ***-1 molecules self-assemble into supramolecular columns with themolecular dipoles aligned along the columnar *** by different host-guest interactions of ethyl acetate(EtOAc)and chloroform(CHCl_(3)),the columns are arranged in an antiparallel and parallel fashion,respectively,leading to a switch of the centrosym metric and noncentrosymmetric *** symmetry of themolecular packing of DC-1 molecules of the noncentrosymmetric crystalline phase is therefore broken,producing a supramolecular ferroelectric with second-harmonic generation and piezoelectric *** demonstrate that cages can serve as promising building blocks for the discovery of supramolecular materials with emergent functions and properties,including but not limited to,organic ferroelectrics and nonlinear optics.

关键词： dissymmetric cage guest-responsive hierarchical self-assembly symmetry breaking supramolecular ferroelectric

Spatial characteristics of the stability of mangrove ecosystems in freshwater and seawater floods in Southeast Asia

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Journal of Geographical Sciences 2022年第9期32卷 1831-1846页

作者： LI Xia LIU Zhenhai wang shaoqiang LI Fengting LI Hui ZHU Tongtong QIAN Zhaohui TU Yongkai LIU Yuanyuan wang Xiaobo wang Qinyi SHI Weibo LI Donghui College of Environmental Science and Engineering Tongji UniversityShanghai200092China Foreign Environmental Cooperation Center Ministry of Ecology and EnvironmentBeijing100035China Key Laboratory of Regional Ecology and Environmental Change School of Geography and Information EngineeringChina University of GeosciencesWuhan430074China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan430074China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing100049China

In tropical regions,mangrove forests are located in the inter-tidal areas between land and sea,and are at risk from both freshwater and seawater *** satellite-derived Normalized Difference Vegetation Index(NDVI)products,this study compared the differences in resistance and resilience of mangrove ecosystems to freshwater and seawater floods in Southeast Asia,and analyzed the spatial characteristics of the stability of mangrove ecosystems under floods in representative *** show that mangroves tended to have lower mean resistance(28.24 vs.37.32)and higher mean resilience(3.74 vs.3.56)under freshwater floods,compared to seawater *** resistance increased with the distance from rivers,such that the resistance of coastal areas to freshwater and seawater floods was lower than that of inland *** areas with lower resistance showed higher resilience compared to those with higher *** mangroves hardly fully recovered to their normal NDVI levels one year after seawater floods,especially in coastal *** the occurrence of seawater floods was relatively rare in the past,it is likely to increase under more-intense climate extremes in the future,and the threat to the survival of mangroves may also ***,it is essential to evaluate the stability of mangrove ecosystems under floods.

关键词： mangrove flood ecosystem stability resistance resilience Southeast Asia

Vegetation and soil carbon storage in China

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Science China Earth Sciences 2004年第1期47卷 49-57页

作者： LI Kerang, wang shaoqiang & CAO MingkuiInstitute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Department of Geography, Maryland University, College Park,MD 20742, USA Correspondence should be addressed to Li Kerang Inst. of Geogr. Sci./Nat. Rsrc. Res. Chinese Academy of Sciences Beijing 100101 China Department of Geography Maryland University College Park MD 20742 United States

This study estimated the current vegetation and soil carbon storage in China using a biogeochemical model driven with climate, soil and vegetation data at 0.5°latitude-longitude grid spatial resolution. The results indicate that the total carbon storage in China's vegetation and soils was 13.33 Gt C and 82.65 Gt C respectively, about 3% and 4% of the global total. The nationally mean vegetation and soil carbon densities were 1.47 kg C/m2 and 9.17 kg C/m2, respectively, differing greatly in various regions affected by climate, vegetation, and soil types. They were generally higher in the warm and wet Southeast China and Southwest China than in the arid Northwest China; whereas vegetation carbon density was the highest in the warm Southeast China and Southwest China, soil carbon density was the highest in the cold Northeast China and southeastern fringe of the Qinghai-Tibetan Plateau. These spatial patterns are clearly correlated with variations in the climate that regulates plant growth and soil organic matter decomposition, and show that vegetation and soil carbon densities are controlled by different climatic factors.

关键词： carbon storage, vegetation, soil, China.

Altered trends in carbon uptake in China's terrestrial ecosystems under the enhanced summer monsoon and warming hiatus

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National Science Review 2019年第3期6卷 505-514页

作者： Honglin He shaoqiang wang Li Zhang Junbang wang Xiaoli Ren Lei Zhou Shilong Piao Hao Yan Weimin Ju Fengxue Gu Shiyong Yu Yuanhe Yang Miaomiao wang Zhongen Niu Rong Ge Huimin Yan Mei Huang Guoyi Zhou Yongfei Bai Zongqiang Xie Zhiyao Tang Bingfang Wu Leiming Zhang Nianpeng He Qiufeng wang Guirui Yu Synthesis Research Center of China's Ecosystem Research Network Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences Sino-French Institute for Earth System Science College of Urban and Environment Sciences Peking University Key Laboratory of Alpine Ecology and Biodiversity Institute of Tibetan Plateau Research CAS Center for Excellence in Tibetan Plateau Earth Science Chinese Academy of Sciences National Meteorological Center China Meteorological Administration International Institute for Earth System Science and Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology Nanjing University Key Laboratory of Dryland Agriculture MOA Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences School of Geography Geomatics and Planning Jiangsu Normal University State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems South China Botanical Garden Chinese Academy of Sciences Department of Ecology College of Urban and Environmental Science Key Laboratory for Earth Surface Processes of the Ministry of Education Peking University Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences

The carbon budgets in terrestrial ecosystems in China are strongly coupled with climate changes. Over the past decade, China has experienced dramatic climate changes characterized by enhanced summer monsoon and decelerated warming. However, the changes in the trends of terrestrial net ecosystem production(NEP) in China under climate changes are not well documented. Here, we used three ecosystem models to simulate the spatiotemporal variations in China’s NEP during 1982–2010 and quantify the contribution of the strengthened summer monsoon and warming hiatus to the NEP variations in four distinct climatic regions of the country. Our results revealed a decadal-scale shift in NEP from a downtrend of–5.95 TgC/yr~2(reduced sink) during 1982–2000 to an uptrend of 14.22 TgC/yr~2(enhanced sink) during 2000–10. This shift was essentially induced by the strengthened summer monsoon, which stimulated carbon uptake, and the warming hiatus, which lessened the decrease in the NEP trend. Compared to the contribution of 56.3% by the climate effect, atmospheric CO2concentration and nitrogen deposition had relatively small contributions(8.6 and 11.3%, respectively) to the shift. In conclusion, within the context of the global-warming hiatus, the strengthening of the summer monsoon is a critical climate factor that enhances carbon uptake in China due to the asymmetric response of photosynthesis and respiration. Our study not only revealed the shift in ecosystem carbon sequestration in China in recent decades, but also provides some insight for understanding ecosystem carbon dynamics in other monsoonal areas.

关键词： climate change Asian summer monsoon warming hiatus biogeochemical modeling ecosystem carbon dynamics

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抽象艺术的归纳与演绎——从包豪斯到当代

美术 2020年第6期 122-127页

作者：王绍强广东美术馆

对于艺术具象和抽象的解读,让我们不停地质疑艺术多元的表现方式与世界相互之间的作用和关系问题。在这个庞大而复杂的实验中,本文在图文互证的背景中展开了新一轮的探索,我们将聚焦当代艺术的历史和当下、民族性与国际性、本体与客体... 详细信息

对于艺术具象和抽象的解读,让我们不停地质疑艺术多元的表现方式与世界相互之间的作用和关系问题。在这个庞大而复杂的实验中,本文在图文互证的背景中展开了新一轮的探索,我们将聚焦当代艺术的历史和当下、民族性与国际性、本体与客体、主观和客观知觉等概念以及艺术性视象与纯粹可视性理论的解读和创作等一系列问题。

关键词：东方哲学抽象艺术复式

Spatiotemporal pattern of the dynamics in area,production,and yield of Aus rice in Bangladesh and its response to droughts from 1980 to 2018

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Journal of Geographical Sciences 2022年第10期32卷 2069-2084页

作者： KHONDAKAR Arifuzzaman DONG Jinwei LI Zhichao DENG Xiangzheng SINGHA Mrinal RAHMAN Md.Mizanur JIN Zhenong wang shaoqiang ZHEN Lin XIAO Xiangming Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China University of Chinese Academy of Sciences Beijing 100094China Department of Geography and Environment Pabna University of Science and TechnologyPabna 6600Bangladesh Deputy Director(Monitoring) Field Services WingDepartment of Agricultural ExtensionMinistry of AgricultureBangladesh Department of Bioproducts and Biosystems Engineering University of Minnesota-Twin CitiesSaint PaulMNUSA Institute of Geographic Sciences and Natural Resources Research CASBeijing 100101China Department of Microbiology and Plant Biology University of OklahomaNorman OK 73019USA

Bangladesh is one of the most vulnerable countries to natural disasters such as droughts in the *** pre-monsoon Aus rice in Bangladesh depends on rainfall and is threatened by increasing ***,limited information on the changes in Aus rice as well as droughts hamper our understanding of the country’s agricultural resilience and adaption to ***,we collected all the official statistical data of Aus rice at the district level from 1980 to 2018,and examined the interannual variations of area,yield,and *** results showed both area and production of Aus rice decreased significantly(61.58×103 ha yr-1 and 17.21×103 *** yr-1,respectively),while yield increased significantly(0.03 *** ha-1 yr-1).We also found a significantly increasing trend of droughts in 88%of area based on the Palmer Drought Severity Index(PDSI)data,especially in those rainfed agricultural ***,we found significant positive correlations between PDSI and Aus rice area(production)in 33(25)out of 64 *** is hardly a relationship between PDSI and yield,likely due to the improved management and increasing irrigated *** continuous drought monitoring,combined irrigation(surface and groundwater)systems,and conservation and precision agriculture are highly recommended in these drought-prone districts to ensure food security in Bangladesh.

关键词： Aus rice droughts acreage production yield PDSI Bangladesh

The Bowen Ratio of an Alpine Grassland in Three-River Headwaters, Qinghai-Tibet Plateau, from 2001 to 2018

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Journal of Resources and Ecology 2021年第3期12卷 305-318页

作者： ZHAO Xuanlan wang Junbang YE Hui MUHAMMAD Amir wang shaoqiang National Ecosystem Science Data Center Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China College of Tourism and Geography JiuJiang UniversityJiujiangJiangxi 332005China

The Bowen ratio(β) is used to quantify heat transfer from the land surface into the air, which is becoming a hot topic in research on the biogeophysical effects of land use and cover changes. The Three-River Headwaters(TRH), as a sensitive and fragile region, was selected as the study area. The β for 2001–2018 was estimated from the evapotranspiration product(ETMOD16) of MODIS and the net radiation of the land surface through the albedo from GLASS. The ETMOD16 data were evaluated against the observation data(ETOBS) at two alpine grassland flux towers obtained from ChinaFLUX. The interannual trend of the β was analyzed by multiple linear regression(MLR) and structure model(SEM) with the multiple factors of precipitation, temperature, humidity, albedo, and normalized difference vegetation index(NDVI, MOD09 Q1). The results show that the ETMOD16 values were significantly correlated with ETOBS, with a correlation coefficient above 0.70(P < 0.01) for the two sites. In 2001–2018, the regional mean β was 2.52 ± 0.77 for the whole grassland, and its spatial distribution gradually increased from the eastern to western region. The interannual β showed a downward trend with a slope of-0.025 and a multiple regression coefficient(R^(2)) of 0.21(P = 0.056). Most of the variability(51%) in the interannual β can be explained by the linear regression of the above multiple factors, and the temperature plays a dominant role for the whole region. The SEM analysis further shows that an increasing NDVI results in a decreasing albedo with a path coefficient of-0.57, because the albedo was negatively correlated with NDVI(R^(2) = 0.52, P < 0.01), which indicates a negative and indirect effect on β from vegetation restoration. An obvious warming climate was found to prompt more evapotranspiration, and restoring vegetation makes the land surface receive more radiation, which both resulted in a decreasing trend in the annual β. This study revealed the biogeophysical mechanisms of vegetation re

关键词： alpine grassland Bowen ratio Three-River Headwaters MODIS evapotranspiration