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Characteristics of the modern pollen assemblages from different vegetation zones in Northeast China:Implications for pollen-based climate reconstruction

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Science China Earth Sciences 2019年第10期62卷 1564-1577页

作者： Qiaoyu CUI Yan ZHAO Feng QIN Chen lIANG Quan lI Rongwei GENG Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing100101China University of Chinese Academy of Sciences Beijing100049China

Northeast China is an essential area for studying the strength of East Asian Summer Monsoon(EASM), due to its northernmost location in EASM domain. However, the lack of sufficient modern pollen data in this region hinders an effective interpretation of fossil pollen records and quantitative vegetation/climate reconstructions. Here, 44 surface pollen samples from forest, steppe, and meadow were used to explore pollen-vegetation-climate relationships. Cluster analysis, species indicator analysis, and principal components analysis, were used to identify the discontinuous and continuous trends in pollen dataset. In addition, correlation analysis and boosted regression trees were used to investigate primary explanatory variables, while coinertia analysis and redundancy analysis to examine pollen-vegetation and pollen-climate correlations respectively. Our results show that:(1) vegetation can be well represented by surface pollen assemblages, i.e. forest is characterized by a high proportion of tree pollen(>70%) dominated by Betula(>40%) along with Alnus, larix, and Pinus, whereas Steppe by herb pollen(>80%),dominated by Artemisia, Chenopodiaceae;(2) significant correlations exist between pollen assemblages and mean annual temperature and then mean annual precipitation;(3) pollen ratios of Artemisia/Chenopodiaceae and arboreal/non-arboreal can respectively be used as good indicators of humidity and temperature in Northeast China.

关键词： Northeast China Modern pollen assemblages Pollen-vegetation relationships Pollen-climate relationships Climate reconstruction

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Different Effects of Increased Water and Nitrogen on Seasonal Soil N2o Emissions from Native Semiarid Grassland in Inner Mongolia, China

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SSRN 2022年

作者： Guo, Yu Peng, Qin Qi, Yunchun li, Zhaolin Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing100101 China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing100085 China National Observation and Research Station of Earth Critical Zone on the Loess Plateau in Shaanxi Xi’an710061 China

Semi-arid temperate grasslands in northern China were wildly considered as the source of the greenhouse gases nitrous oxide (N2O). Since the annual precipitation and nitrogen (N) deposition were predicted to increase, individual and interactive effects of water or N addition on N2O emissions had been attracted much attention. However, their effects during non-growing season were still limited. We investigated the dynamic of year-round N2O emission after 4-years water and N addition in a typical semi-arid temperate grassland in Inner Mongolia grassland in this study. The results confirmed the semi-arid temperate grassland as a source of N2O emission. The meteorological events and the treatments resulted in variation of N2O fluxes. The N2O emission from non-growing season accounted for approximately 65% of annual budget. But the emission pulses before winter cover less than 5%. The temperature dominated the patterns of N2O emission for both growing season and non-growing season. And the effects of water and N addition on N2O emission showed differences for growing and non-growing season. The effects on N2O emissions were more intensity during growing season, showed directly and indirectly pathways. But the effects took place indirectly through soil moisture and substation and MBC during non-growing season. © 2022, The Authors. All rights reserved.

关键词： Climate change

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Characterization and Role of Molecular Size-Fractionated Colloids on Arsenic Mobilization in surface Water Around Shimen Realgar Mine

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SSRN 2022年

作者： Yu, Zhenzhen Yang, Fen li, Zhiying Wei, Chaoyang Jiang, Bin Dai, Weijie Feng, Hanxiao Zhang, Ping Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing100101 China Institute of Geographical Sciences Henan Academy of Sciences Zhengzhou450052 China State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou510640 China University of Chinese Academy of Sciences Beijing100049 China

The mobility and transport of As in natural water are largely influenced by the inorganic components and dissolved organic matter (DOM) of colloids, but little is known about the characteristics of different molecular weights (MW) of colloids and their impacts on As mobilization. Therefore, the bulk surface water ( © 2022, The Authors. All rights reserved.

关键词： surface waters

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Advanced Autumn Phenology Shortened the length of the Growing Season Over the Great lakes Region of Central Asia from 1982 to 2014

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SSRN 2022年

作者： Gao, Xuan Zhao, Dongsheng Key laboratory of land surface pattern and simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences No. 11A Datun Road Chaoyang District Beijing100101 China University of Chinese Academy of Sciences No. 19A Yuquan Road Shijingshan District Beijing100049 China

Dryland ecosystems in the Great lakes Region of Central Asia (GlRCA) are highly sensitive to climate change due to the climate of spring precipitation. Although shifts in vegetation phenology have been widely attributed to rising temperature, the effects of solar radiation and drought on phenology remain largely unknown in the GlRCA. Understanding the mechanisms of vegetation phenology response to climatic factors is essential for assessing the impact of climate change on dryland ecosystems. In this study, we investigated the spatial and temporal variations of vegetation phenology across the GlRCA using a long-term series of Normalized Difference Vegetation Index (NDVI), and then examined the response of vegetation phenology to climate change within different climate zones by combining with climate data (surface temperature, soil moisture, short-wave radiation, and standardized precipitation evapotranspiration index (SPEI)). The results suggested that the start of growing season (SGS) and the end of growing season (EGS) were significantly earlier at the regional scale. Because of changes in SGS and EGS, length of growing season (lGS) across the GlRCA was shortened regionally at a rate of -0.442 days/yr, which was mainly attributed to advanced EGS. Additionally, SGS of vegetation was negatively correlated with surface temperature but positively correlated with soil moisture and SPEI. These results indicated that surface temperature was a major determinant of advanced spring phenology, while increased soil moisture and mitigated drought would delay spring phenology. The response of autumn phenology to surface temperature and short-wave radiation varied across different climate zones. In arid climate zone, autumn phenology was obviously advanced with the increase of surface temperature and short-wave radiation. In cold climate zone, higher surface temperature and short-wave radiation postponed autumn phenology. Meanwhile, the thermal growing season did not accurately c

关键词： Climate change

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Economic development lowering inequality in China's household food greenhouse gas footprints

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Cell Reports Sustainability 2024年第12期1卷

作者： liu, Gang Zhang, Fan Deng, Xiangzheng School of Urban Economics and Public Administration Capital University of Economics and Business Beijing China 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 School of Economics and Management University of Chinese Academy of Sciences Beijing China Beijing Technology and Business University Beijing China

Humans have persistent food needs that trigger considerable greenhouse gas emissions, varying significantly by region. However, the greenhouse gas footprint and inequality are not well characterized within countries. Here, we quantify China's national and sub-national food greenhouse gas footprint from 2007 to 2017 using a multi-regional input-output framework and evaluate inequalities using the Gini coefficient. Our results reveal a decline in environmental pressures from household food consumption. The national per capita footprint declined from 0.66 to 0.53 tCO₂-equivalent over the decade, with a similar trend in most provinces. Substantial differences across households between and within provinces are evident, with wealthier provinces exhibiting lower inequality compared with lower-income provinces. The national food greenhouse gas footprint Gini coefficient declined from 0.356 to 0.339 with economic development, while almost all provinces, except for Shaanxi, experienced declining Gini coefficients. This study highlights the declining trend in food greenhouse gas footprint inequality alongside economic growth. © 2024 The Authors

关键词： carbon emissions climate change mitigation food system greenhouse gas footprint household consumption inequality input-output analysis SDGs supply chains

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Co-Occurrence of Geogenic Thallium and Arsenic in surface Water and Hot Springs

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SSRN 2022年

作者： Wen, Qiqian Yang, linsheng Gong, Hongqiang Yu, Jiangping Wei, Binggan Zhao, Shengcheng Tu, Dan Yin, Shuhui Wang, Ting Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 11 A Datun Road Beijing100101 China College of Resources and Environment University of Chinese Academy of Sciences Beijing100190 China Tibet Autonomous Region Center for Disease Control and Prevention Lhasa850030 China

The Tibetan Plateau (TP) is known as the water tower of Asia. Water quality has long been a focus of public concern in this climate-sensitive and geologically complex area, especially in the Yarlung Tsangpo River Basin (YTRB), where population and agriculture are concentrated. Thallium (Tl) is a typical metal of severe toxicity and often occurs together with arsenic (As) in sulfide minerals. Considering the large-scale polymetallic sulfide mineralization developed in the YTRB, high concentrations of As have been reported in water. However, equally important but often overlooked is the co-enrichment of geogenic Tl and As in surface water and groundwater. In this study, the enrichment, spatial distribution, geologic origins, and interrelationships of Tl and As in hot springs and surface water in the YTRB were systematically analysed. The results show that high levels of Tl (0.001-5.146 μg/l) and As (0.2-5435.5 μg/l) were present in hot springs. The contents of Tl (0.002-0.264 μg/l) and As (0.4-649.0 μg/l) in surface water were affected by the runoff from hot springs. There was a strong positive spatial correlation between Tl and As in hot springs and surface water. The co-enrichment and spatial relationships of As and Tl could be attributed to plate subduction, the reduction–dissolution of Tl (As)-bearing minerals, and hydrothermal fluids. This study offers valuable insights into the potential co-pollution of geogenic Tl and As. Of particular note is that areas with As-rich groundwater and rich sulfide mineralization may also experience potential Tl risk. © 2022, The Authors. All rights reserved.

关键词： Groundwater

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Future Population Exposure to Heatwaves in 83 Global Megacities

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SSRN 2023年

作者： Wang, Yuwei Zhao, Na Wu, Chaoyang Quan, Jinling Chen, Mingxing State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing100101 China College of Resources and Environment University of Chinese Academy of Sciences Beijing100049 China Jiangsu Center for Collaborative Innovation in Geographic Information Resource Development and Application Nanjing210023 China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing100101 China Key Laboratory of Regional Sustainable Development Modelling Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing100101 China

Global warming leads to more frequent and intense heatwaves, putting urban populations at greater risk. Previous related studies considered only surface air temperature or 1-2 shared socioeconomic pathways (SSPs), and were limited to specific regions. Moreover, no research focused on heatwave exposure in highly-populated global megacities facing severe threats. This study is the first to project future population exposure to heatwaves in 83 global megacities by 2100 using fine-resolution data, suitable indices reflecting human comfort in heatwaves by incorporating temperature and humidity, and a future population exposure projection and analysis framework. The results show that (1) the global frequency of extreme heatwave events and average change rate in each megacity sequentially increase from SSP126 to SSP585, and the change rate is generally larger in megacities in the Southern Hemisphere;(2) the increases in heatwave exposure are greatest under SSP370, and the change rates are generally larger for megacities in southern Asia;(3) there is a high degree of inequality (Gini of 0.6 to 0.63) in future heatwave exposure globally, with the highest inequality under SSP585 and the lowest under SSP370;(4) the average exposure, increase rate and change are highest in low-income megacities and lowest in high-income megacities. The distribution of exposure is the most balanced in middle-income megacities and the least balanced in high-income megacities;and (5) population growth contributes more to the change in exposure than total warming in high-income megacities under SSP126;and total urban warming contributes much more than population growth in all other cases. Every effort should be made to avoid SSP370 scenario and pursue sustainable and rational urban economic development. Mumbai, Manila, Kolkata, and Jakarta warrant particular attention due to their rapid exposure growth. Additionally, policymakers and urban planners must focus on improving sustainable development pl

关键词： Population statistics

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Inconsistency and Correction of Manually Observed Ground surface Temperatures Over Snow-Covered Regions

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SSRN 2023年

作者： Cao, Bin Wang, Shengdi Hao, Jiansheng Sun, Wen Zhang, Kun Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing100101 China College of Earth and Environmental Sciences Lanzhou University Lanzhou730000 China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing100101 China Department of Mathematics The University of Hong Kong 999077 Hong Kong School of Biological Sciences The University of Hong Kong 999077 Hong Kong

Ground surface temperature (Ts) was manually measured using mercury thermometers in the early stage, and the snow surface temperature was used as Ts in areas with thick seasonal snow covers due to measurement difficulty. This practice produced Ts data that are inconsistent with more recent automatic measurements using modern instrumentation, which determine ground surface temperature in the soil beneath the snow cover. In this study, we used the observations from northeastern China to explore and correct the Ts inconsistency. The resulting Ts inconsistency varies from a few degrees to tens of degrees depending on the snow conditions and time periods considered. This inconsistency between earlier and modern measurements results in the overestimation of soil temperature warming rate in recent decades. We remove the Ts inconsistency using a numerical model that considers the effect of snow insulation on ground surface temperatures. This approach provides the means and opportunity to improve Ts records that have similarly switched from manual to automatic measurements, which is critical for soil and climate investigations. © 2023, The Authors. All rights reserved.

关键词： Snow

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Principles and research progress of physical prevention and control technologies for algae in eutrophic water

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iScience 2024年第6期27卷 109990页

作者： Wang, Yuyao Zhu, Yuanrong Wang, Kuo Tan, Yidan Bing, Xiaojie Jiang, Juan Fang, Wen Chen, liang liao, Haiqing State Key Laboratory of Environment Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences Beijing 100012 China College of Geography and Environmental Science Northwest Normal University Lanzhou 730070 China School of Energy and Environmental Engineering University of Science and Technology Beijing Beijing 100083 China College of Environment Hohai University Nanjing 210098 China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China School of Water Conservancy and Environment University of Jinan Jinan 250022 China

The abnormal reproduction of algae in water worldwide is prominent in the context of human interference and global climate change. This study first thoroughly analyzed the effects of physical factors, such as light, temperature, hydrodynamics, and operational strategies, on algal growth and their mechanisms. Physical control techniques are safe and have great potential for preventing abnormal algal blooms in the absence of chemical reagents. The focus was on the principles and possible engineering applications of physical shading, ultrasound, micro-current, and ultraviolet (UV) technologies, in controlling abnormal algal reproduction. Physical shading can inhibit or weaken photosynthesis in algae, thereby inhibiting their growth. Ultrasound mainly affects the physiological and biochemical activities of cells by destroying the cell walls, air cells, and active enzymes. Micro-currents destroy the algal cell structure through direct and indirect oxidation, leading to algal cell death. UV irradiation can damage DNA, causing organisms to be unable to reproduce or algal cells to die directly. This article comprehensively summarizes and analyzes the advantages of physical prevention and control technologies for the abnormal reproduction of algae, providing a scientific basis for future research. In the future, attempts will be made toward appropriately and comprehensively utilizing various physical technologies to control algal blooms. The establishment of an intelligent, comprehensive physical prevention and control system to achieve environmentally friendly, economical, and effective physical prevention and control of algae, such as the South-to-North Water Diversion Project in China, is of great importance for specific waters. © 2024 The Author(s)

关键词： Environmental engineering Environmental science Water resources engineering

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An integrated approach for determining the spatial distribution, source apportionment and human health risks of PAHs in soils of rapidly-urbanized areas

Soil and Environmental Health

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Soil and Environmental Health 2025年第3期3卷

作者： luo, lingzhi liao, Xiaoyong Tao, Huan li, You Wang, liang Cao, Hongying li, Yonghua Shi, Weiwei Wang, Tianyi Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences (CAS) Beijing 100101 China Beijing Key Laboratory of Environmental Damage Assessment and Remediation Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

The rise of large urban agglomerations has exacerbated pollutant emissions, resulting in regional soil contamination with polycyclic aromatic hydrocarbons (PAHs), which jeopardizes the development of urban agglomerations and affects human health. There is a lack of research in this area in the Beijing-Tianjin-Hebei region, with the existing studies on PAHs in soil in the larger region often neglecting the spatial heterogeneity of the pollution sources and systematic analysis of risk assessment. This study introduces the Distribution-Source-Risk framework, analyzed soil PAH pollutants in the region, and examined PAH sources, distribution patterns, and associated health risks. Random forest modeling was employed to map PAH distribution in the BTH soils. City classification analysis was conducted based on the derived pollution levels and urbanization degree, resulting in four city types: high urbanization and high pollution, high urbanization and low pollution, low urbanization and high pollution, and low urbanization and low pollution. Primary PAH sources include coal-burning (29%), coking (25%), traffic (25%), and biomass-burning (21%), with varying contributions based on city types. The overall order of human health risks was coal-burning > traffic > coking > biomass-burning sources. Finally, differen policies for soil PAH PAH management (such as energy transition and green infrastructure) were elaborated to promote coordinated development of regional urbanization environment. In summary, this research offers a comprehensive approach, linking processes to provide a precise understanding of pollution across different entities (cities, sources, and populations). Our findings reveal distinct pollution patterns across city types and highlight targeted mitigation priorities and provide a systematic, data-driven framework for regional soil PAH management and public health protection. © 2025 The Authors

关键词： Beijing-tianjin-hebei region Distribution patterns Distribution-source-risk framework Health risk assessment High pollution High urbanization Positive matrix factorization Random forest modeling Source apportionment Source-specific risk

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