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Analysis of emergy-based metabolic efficiency and environmental pressure on the local coupling and telecoupling between urbanization and the eco-environment in the Beijing-Tianjin-Hebei urban agglomeration

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Science China Earth Sciences 2017年第6期60卷 1083-1097页

作者： FANG ChuangLin REN YuFei Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

We use emergy-based urban metabolism analysis in this study to investigate the local coupling and telecoupling between urbanization and the eco-environment in the Beijing-Tianjin-Hebei urban agglomeration. Our analysis encompasses the last 35 years spanning the period between 1980 and 2014. In addition, we analyze urban metabolic efficiency and environmental pressure in these couplings. There are three main conclusions of this study. First, we show that the total metabolic emergy value of the Beijing-Tianjin-Hebei urban agglomeration has increased over the last 35 years, and that external elements have replaced internal ones as the leading contributors to urban metabolism in this region. The proportion of metabolic emergy derived from external elements increased from 30.87% in 1980 to 67.43% in 2014. The emergy extroversion ratio has continued to increase over our study period, while the development of this urban agglomeration had become progressively and more heavily reliant on external elements. Second, over the study period, the metabolic emergy intensity of elements of local coupling and telecoupling in the Beijing-Tianjin-Hebei urban agglomeration has declined at an accelerating rate, from 1.15×10^(21) Sej/100 million RMB in1980 to 9.69×10^(19) Sej/100 million RMB in 2014. This reflects a continuous increase in the economic efficiency of this ***, emergy use per capita increased from 7.8×10^(15) Sej/person in 1980 to 5.83×10^(16) Sej/person in 2014, suggesting a gradual rise in the level of social welfare in this urban agglomeration. However, we also observed a consistently elevated environmental loading ratio(ELR) in our analysis in terms of metabolism of local coupling and telecoupling elements. This result indicates that environmental pressure has also increased constantly within the Beijing-Tianjin-Hebei urban agglomeration. Third,our analysis shows that the ELR of metabolic emergy from internal elements increased from 8.30 in 1980 to 43.46

关键词： Urbanization Eco-environment Local coupling and telecoupling Total metabolic emergy value Metabolic emergy intensity environmental pressure Beijing-Tianjin-Hebei urban agglomeration

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A2B2O7 pyrochlore compounds:A category of potential materials for clean energy and environment protection catalysis

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Journal of Rare Earths 2020年第8期38卷 840-849,I0001页

作者： Junwei Xu Rong Xi Xianglan Xu Yan Zhang Xiaohui Feng Xiuzhong Fang Xiang Wang Key Laboratory of Jiangxi Province for environment and Energy Catalysis College of ChemistryNanchang UniversityNanchang 330031China

A2B2O7 pyrochlore is a kind of important functional materials for different purposes,which has been investigated extensively by crystallographers and material ***,the catalytic chemistry of this type of special compounds has rarely been documented,though a few researchers have tried to synthesize some pyrochlore compounds with different chemical compositions for a variety of green energy production and air pollution control reactions in the *** the expectation to help catalysis scientists to get better acquaintance with,and gain deeper understanding on this type of compounds as heterogeneous catalysts,the major publications over the past several decades have been screened and reviewed in this paper,based also on our own experience of studying on this type of catalytic *** crystalline phase transformations of the compounds with the change of the A and B site cations,the phase change’s influences on the surface and bulk properties,and their subsequent impact on the catalytic performance for different reactions have been ***,the future work which needs to be performed to perceive in depth this kind of important materials as catalysts has been proposed and *** trust that this short review contains valuable information,which will provide great help for people to get better cognition for A2 B2 O7 pyrochlore compounds,and assist them to develop better catalysts for various reactions.

关键词： A2B2O7 pyrochlore compounds Crystalline phase change Lattice and surface oxygen vacancies Value-added CH4 transformation Air pollution control reactions Rare earths

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Understanding the risks of mercury sulfide nanoparticles in the environment: Formation, presence, and environmental behaviors

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Journal of environmental Sciences 2022年第9期34卷 78-92页

作者： Pei Lei Nan Zou Yujiao Liu Weiping Cai Mengjie Wu Wenli Tang Huan Zhong State Key Laboratory of Pollution Control and Resource Reuse School of EnvironmentNanjing UniversityNanjing 210023China Key Laboratory of Soil environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China environmental and Life Sciences Program(EnLS) Trent UniversityPeterborough OntarioK9L 0G2Canada

Mercury(Hg) could be microbially methylated to the bioaccumulative neurotoxin methylmercury(Me Hg), raising health concerns. Understanding the methylation of various Hg species is thus critical in predicting the Me Hg risk. Among the known Hg species, mercury sulfide(HgS) is the largest Hg reservoir in the lithosphere and has long been considered to be highly inert. However, with advances in the analytical methods of nanoparticles, HgS nanoparticles(HgS NPs) have recently been detected in various environmental matrices or organisms. Furthermore, pioneering laboratory studies have reported the high bioavailability of HgS NPs. The formation, presence, and transformation(e.g., methylation) of HgS NPs are intricately related to several environmental factors, especially dissolved organic matter(DOM). The complexity of the behavior of HgS NPs and the heterogeneity of DOM prevent us from comprehensively understanding and predicting the risk of HgS NPs. To reveal the role of HgS NPs in Hg biogeochemical cycling, research needs should focus on the following aspects: the formation pathways, the presence, and the environmental behaviors of HgS NPs impacted by the dominant influential factor of DOM. We thus summarized the latest progress in these aspects and proposed future research priorities, e.g., developing the detection techniques of HgS NPs and probing HgS NPs in various matrices, further exploring the interactions between DOM and HgS NPs. Besides, as most of the previous studies were conducted in laboratories, our current knowledge should be further refreshed through field observations, which would help to gain better insights into predicting the Hg risks in natural environment.

关键词： Bioavailability Bioaccumulation Organic matter Mercury methylation Dissolution Aggregation

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Climate and environment reconstruction during the Medieval Warm Period in Lop Nur of Xinjiang, China

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Chinese Science Bulletin 2008年第19期53卷 3016-3027页

作者： MA ChunMei WANG FuBao CAO QiongYing XIA XunCheng LI ShengFeng Li XuSheng School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210093 China Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China

We made multi-proxy analysis of 14C, grain size, microfossils, plant seeds, and geochemical elements on samples from a profile in the central West Lake of Lop Nur. The grain size suggests relatively stable sedimentary environment around the Medieval Warm Period (MWP) with weak storm effect, which is followed by frequent strong storm events. Abundant microfossils and plant seeds in this stage indicate a warm and humid fresh to brackish lake environment. C, N, and stable elements are high in content in the sediments while Rb/Sr, Ba/Sr, and Ti/Sr are in a steady low level. In addition, plenty of red willows lived here prior to about 700 a B.P., indicating a favorable environmental condition. The results indicate that the environment in Lop Nur and its west bank turned to be favorable at about 2200 a B.P., where the Loulan Culture began to thrive. Then the climate and environment came to be in the good condition in the Tang and Song Dynasties, when the storm effect became weaker, rainfall increased and the salty lake water turned to be brackish to fresh lake water. Hence, limnic biomass increased with higher species diversity.

关键词：中世纪新疆气候变化环境进化

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Progress on the mapping of groundwater resources and environment in Asia

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Journal of Groundwater Science and Engineering 2015年第2期3卷 105-117页

作者： ZHANG Fa-wang CHENG Yan-pei Institute of Karst Geology Chinese Academy of Geological Sciences Institute of Hydrogeology and environmental Geology Chinese Academy of Geological Sciences

With the ever-accelerating economic and social growth in Asia,the sustainable development of environment,economy and society of Asia and beyond,is severely constrained by a series of grave issues,such as global climate change,population explosion,resource shortage,and rampant *** need for study on groundwater resources and environment in Asia as part of the efforts to tackle global climate change looms even *** analyzing how global changes of modern times and human activities are related to primary geo-environment,the groundwater environment serial maps of Asia introduces a new concept for mapping geo-environment of Asia that connects the geological background to groundwater *** serial maps reveal the geographic environment that is closely related to groundwater,the special-temporal features of the geo-environment and how it is *** study is vital not only to the harmonious development among environment,economy and society as well as ecological progress in Asia,but also to the strategic requirements posed by the'One Belt One Road'.

关键词： Asia Groundwater resources Groundwater environment Serial maps of groundwater

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Ecological Status and Uses of Juniper Species in the Cold Desert environment of the Lahaul Valley, North-western Himalaya, India

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Journal of Mountain Science 2012年第5期9卷 676-686页

作者： Yashwant S.RAWAT Colin S.EVERSON School of Agricultural Earth and Environmental SciencesUniversity of KwaZulu-Natal

The juniper species Juniperus polycarpos C. Koch, J. indica Bertol. and J. communis L. var. saxatilis （Pallas） are important elements of the forest vegetation in Lahaul valley in the north-western Himalaya. Their ability to grow under the barren and xeric conditions of cold deserts makes them particularly suited for afforestation programmes under these eeologieal conditions. In the Lahaul valley, juniper species are used as subsistence resources and for religious purposes. Excessive removal of juniper wood and leaves by the local population, overgrazing, habitat fragmentation and low regeneration potential are the main obstacles to eonservation of juniper forests in this region. The present study was carried out to assess density, basal area and importance value index （WI） of the local vegetation as well as uses and amounts of juniper wood and leaves removed from the local forests. Pressure on relict juniper forests due to grazing animals and intensive removal of wood and leaves by the loeal population was found to be greater at an altitude above 3,00o m. The results of the study demonstrated that the different juniper speeies were adapted to specific altitude ranges. A higher species density was recorded at lower altitude except for J. indica which was only present at high altitude （〉3,200 m） on south-facing slopes. Density, basal area and IVI of J. polycarpos were higher at Hinsa （2,7oo m） than at Jahlma （3,000 m）. The rapid loss of vegetation due to overuse and habitat degradation has made the eonservation of juniper forests an important priority in the Lahaul valley. J. polycarpos at loweraltitude and J. indica at higher altitude are ecologically the more suitable species for the successful implementation of conservation programmes. The support of rehabilitation programmes by regional authorities is essential for the reestablishment of the local juniper forests.

关键词： Juniper Distribution Utilization Pattern Agroforestry Forest Conservation

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Semantic linking of complex properties,monitoring processes and facilities in web-based representations of the environment

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International Journal of Digital Earth 2016年第3期9卷 300-324页

作者： Adam M.Leadbetter Peter N.Vodden Marine Institute Co.GalwayIreland Centre for Ecology and Hydrology Lancaster Environment CentreLancasterUK

Where a virtual representation of the Earth must contain data values observed within the physical Earth system,data models are required that allow the integration of data across the silos of various Earth and environmental sciences *** a mapping between the well-defined terminologies of these silos is a stubborn *** paper presents a generalised ontology for use within Web 3.0 services,which builds on European Commission spatial data infrastructure *** presented ontology acknowledges that there are many complexities to the description of environmental properties which can be observed within the physical Earth *** ontology is shown to be flexible and robust enough to describe concepts drawn from a range of Earth science disciplines,including ecology,geochemistry,hydrology and *** paper also demonstrates the alignment and compatibility of the ontology with existing systems and shows applications in which the ontology may be deployed.

关键词： observable properties monitoring properties environmental monitoring facilities semantic web geospatial data integration

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Quantitative Analysis on the Relationship between Population Distribution and environment Factors in Mountain Area

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Meteorological and environmental Research 2011年第3期2卷 77-80页

作者： SUN Yu-lian1,2,ZHAO Yong-tao1,CAO Wei-chao1,2,YU Hui1,MA Yue-wei1,2 1.Institute of Mountain Hazards and environment,Chinese Academy of Sciences,Chengdu 610041,China 2.Graduate University of Chinese Academy of Sciences,Beijing 100049,China

[Objective] The aim was to analyze the relationship between population distribution and environment factors in mountain area quantitatively.[Method] Taking the contiguous area of Sichuan,Yunnan and Guizhou Province as study object,population density and residential point density were chosen as the indices of population distribution,and the quantitative relationship between population distribution and environment factors (including altitude,topography relief amplitude,land use,road network and river network) in mountain area was analyzed.[Result] Altitude and topography relief amplitude in mountain area had obvious negative correlation with population density and residential point density,and the correlation coefficients with population density were-0.731 *** addition,residential points were fewer in the region far from rivers,but there was no obvious correlation between population density and river network *** point density was higher in cultivated land and construction land,and population density had obvious positive correlation with the area proportions of cultivated land and construction land,with the correlation coefficients of 0.895 and 0.726,***,the more distant from road,the smaller residential point density,and there was obvious positive correlation between population density and road network density,with the correlation coefficient of 0.823.[Conclusion] The study could lay a foundation for the further development of spatiality of population data in study region.

关键词： Population distribution environmental factors Quantitative analysis Mountain area China

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Fatigue test of carbon epoxy composite high pressure hydrogen storage vessel under hydrogen environment

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第6期14卷 393-400页

作者： Chuan-xiang ZHENG Liang WANG Rong LI Zong-xin WEI Wei-wei ZHOU Institute of Chemical Machinery and Process Equipment Zhejiang University

A significant temperature raise within hydrogen vehicle cylinder during the fast filling process will be observed, while the strength and fatigue life of the cylinder will dramatically decrease at high temperature. In order to evaluate the strength and fatigue of composite hydrogen storage vessel, a 70-MPa fatigue test system using hydrogen medium was set up. Experimental study on the fatigue of composite hydrogen storage vessels under real hydrogen environment was performed. The experimental results show that the ultimate strength and fatigue life both decreased obviously compared with the values under hydraulic fatigue test. Furthermore, fatigue property, failure behavior, and safe hydrogen charging/discharging working mode of onboard hydrogen storage vessels were obtained through the fatigue tests.

关键词： Hydrogen storage vessel Composite Fatigue test High pressure Temperature raise

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Prediction of spatial land use changes based on LCM in a GIS environment for Desert Wetlands-A case study: Meighan Wetland,Iran

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International Soil and Water Conservation Research 2019年第1期7卷 64-70页

作者： Amir Ansari Mohammad H.Golabi Department of environmental Sciences Faculty of Agriculture and Natural ResourcesArak UniversityArak 38156-8-8349Iran College of Natural and Applied Sciences University of Guam MangilaoGuam 96923United States

Meighan Wetland and its surroundings have undergone many changes in recent *** study aims to monitor and predict land use changes using the land change model (LCM) module in the Meighan *** Sat images of years 2000,2007 and 2015 were used to produce digital land use *** images were classified into seven classes including;Salt lake,Agriculture,Rangeland,Manmade,Wastewater,Wetland and Mine *** LCM module in Idrisi GIS software was used to analyze the land use changes for predicting the land uses status in 2015,based on artificial neural network (ANN) and Markov Chain *** ANN was trained with various influencing factors including;distance from road,distance from manmade areas,distance from land changed edge,distance from stream,elevation and *** results indicated that 1663.88 ha of the rangeland cover and 715.68 ha of the salt lake cover have been degraded during the 2000-2015 ***,the wetland,mine,wastewater and manmade degradation are increased to 724 ha,335 ha,37 ha and 270 ha in comparison to initial land ***,the result shows that rangeland and salt lake areas will decrease in the year 2030 compare to 2015,while,wetland,mine and manmade land changes may increase.

关键词： LCM Prediction Meighan wetland Land use changes Artificial Neural Network

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