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中化环境:科改激发活力 打造环保新锐
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作者 崔焱 《企业管理》 2021年第3期85-87,共3页
"科改示范企业"中化环境控股有限公司(简称中化环境)是中国中化集团有限公司的全资子公司,2018年9月由原中化节能环保控股(北京)有限公司增资重组而成,定位为工业园区和工业企业全生命周期综合环境服务和系统解决方案提供商... "科改示范企业"中化环境控股有限公司(简称中化环境)是中国中化集团有限公司的全资子公司,2018年9月由原中化节能环保控股(北京)有限公司增资重组而成,定位为工业园区和工业企业全生命周期综合环境服务和系统解决方案提供商。中化环境以"科改示范行动"为契机,充分发挥党组织的政治核心和领导核心作用,通过建立市场化选人用人机制、完善创新激励机制、加强企业文化建设,有力推动企业高质量发展。2020年,公司克服新冠肺炎疫情影响,实现营业收入10.26亿元、净利润8700万元,同比分别增长54%和65%。 展开更多
关键词 中化环境 科改示范企业 全链条激励图谱 三心工程
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The eco-environmental guarantee for China's urbanization process 被引量:15
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作者 方创琳 蔺雪芹 《Journal of Geographical Sciences》 SCIE CSCD 2009年第1期95-106,共12页
Studying the change of resources consumption and eco-environmental carrying capacity are of importance to the sustainable development of urbanization.Based on the China's economic and social statistical data from ... Studying the change of resources consumption and eco-environmental carrying capacity are of importance to the sustainable development of urbanization.Based on the China's economic and social statistical data from 1950 to 2006,the ecological footprint,eco-logical footprint intensity,ecological deficit and surplus,and eco-environment quality com-prehensive index are calculated,the correlation between urbanization and eco-environmental change is analyzed and the eco-environmental guarantee for China's urbanization in 2030 is forecasted.The major results could be summarized as follows:(1) there is a positive linear relation between urbanization and ecological footprint,negative linear relation between ur-banization and ecological footprint intensity,ecological deficit and surplus and the negative exponential relation between urbanization and eco-environment quality comprehensive index.(2) By 2030,the urbanization level will reach 61.32%,the ecological deficit will increase to 42.2866×108 hm2 and the eco-environment quality comprehensive index will drop to 0.3016 on the condition that the total quantity ecological footprint achieves 55.9348×108 hm2.(3) Under the existing urban development pattern,the ecological overload will be more serious in the next 24 years.Constructing the reasonable industrial structure and establishing the intensive resources utilization system to alleviate the eco-environmental pressure are the tough challenges in China's urbanization process. 展开更多
关键词 URBANIZATION eco-environmental guarantee coupling relationship ecological footprint China
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Soil Organic Carbon and Labile Carbon Along a Precipitation Gradient and Their Responses to Some Environmental Changes 被引量:12
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作者 WANG Shu-Ping ZHOU Guang-Sheng +1 位作者 GAO Su-Hua GUO Jian-Ping 《Pedosphere》 SCIE CAS CSCD 2005年第5期676-680,共5页
Based on data from a field survey in 2001 along the Northeast China transect (NECT), a precipitation gradient,and a short-term simulation experiment under ambient CO2 of 350 μmol mol-1 and doubled CO2 of 700 μmol mo... Based on data from a field survey in 2001 along the Northeast China transect (NECT), a precipitation gradient,and a short-term simulation experiment under ambient CO2 of 350 μmol mol-1 and doubled CO2 of 700 μmol mol-1with different soil moisture contents of 30%-45%, 45%-60%, and 60%-80% soil water holding capacity, the distributionof soil organic carbon and labile carbon along the NECT, their relationships with precipitation and their responses toCO2 enrichment and soil moisture changes were analyzed. The results indicated that the soil labile carbon along thegradient was significantly related to soil organic carbon (r = 0.993, P < 0.001). The soil labile carbon decreased morerapidly with depth than organic carbon. The soil organic and labile carbon along the gradient decreased with decrease inlongitude in both the topsoils and subsoils, and the coefficient of variation for the labile carbon was greater than that forthe organic carbon. Both the soil organic carbon and labile carbon had significant linear relationships with precipitation,with the correlation coefficient of soil organic carbon being lower (0.677 at P < 0.001) than that of soil labile carbon(0.712 at P < 0.001). In the simulation experiment with doubled and ambient CO2 and different moisture contents, thecoefficient of variation for soil organic carbon was only 1.3%, while for soil labile carbon it was 29.7%. With doubled CO2concentration (700 μmol mol-1), soil labile carbon decreased significantly at 45% to 60% of soil moisture content. Theseindicated that soil labile carbon was relatively more sensitive to environmental changes than soil organic carbon. 展开更多
关键词 environmental changes labile carbon organic carbon precipitation gradient SOIL
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Roles of State Strategy of Adaptation to Climate Change in China 被引量:3
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作者 Jiang Dongmei Wang Can +1 位作者 Huang Shanfeng Zhang Mengheng 《Chinese Journal of Population,Resources and Environment》 北大核心 2007年第4期74-80,共7页
For the adverse impacts of climate change, China gov- ernment should place the problem of adaptation to climate change on the agenda. It is time to institute and implement a state adap- tive strategy to reduce the adv... For the adverse impacts of climate change, China gov- ernment should place the problem of adaptation to climate change on the agenda. It is time to institute and implement a state adap- tive strategy to reduce the adverse impacts on economy, commu- nity and people's health and life by international cooperation and our own endeavor. A state strategy of adaptation to climate change should be closely linked with other current interrelated national strategies, and they should be supplemented and improved by each other. This paper discusses the roles of the state strategy of adaptation to climate change in the state climate change integra- tive strategy, the environmental protection strategy, and the sus- tainable development strategy in China. Furthermore, it proposes the main aims of the state adaptive strategy of China. 展开更多
关键词 adaptation to climate change state strategy ROLES
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Coordination of Urbanization and Water Ecological Environment in Shayinghe River Basin,China 被引量:7
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作者 ZHANG Xiang HU Hong +1 位作者 XU Jiangang YIN Haiwei 《Chinese Geographical Science》 SCIE CSCD 2011年第4期476-495,共20页
During the rapid industrialization and urbanization of China,urban agglomeration in river basin areas raises the problems of over-use of water resources and pollution of the water environment.Related research in China... During the rapid industrialization and urbanization of China,urban agglomeration in river basin areas raises the problems of over-use of water resources and pollution of the water environment.Related research in China has mainly focused on the conflicts among economic growth,urban expansion and water resource shortages within admin-istrative boundaries.However,water environments are much more dependent on their physical boundaries than their administrative boundaries.Consistent with the nature of water environment,this study aims at analyzing coordination relationships between urban development and water environment changes within physical river basin boundaries.We chose the Shayinghe River Basin,China,as our case study area which is facing serious challenges related to water en-vironment protection.Then we classified 35 county-level administrative units into upstream,midstream and down-stream regions based on their physical characteristics;analyzed the coordination degree of urban agglomeration using the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method;and constructed cooperative models using the Linear Programming (LP function) to simulate four scenarios of the coordination relationship be-tween urban population increase and water environment protection based on existing water resources and water pollu-tion data.The results show that the present coordinative situation in Shayinghe River Basin is not sustainable.In gen-eral,more than 50% administrative units are in the bad coordinative situation.In particular,the downstream region is under worse condition than the upstream and midstream regions.Cooperative models in scenario analyses indicate that the population scale set in existing urban master plannings is not coordinated with the water environment protection.To reach the goal of regional sustainable development,the total population needs to be controlled such that it will re-main at 4.5×10 7 or below by 2020 given the capacity of water environment. 展开更多
关键词 water ecological environment coordination analysis cooperative model urban agglomeration Shayinghe River Basin
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Water Security Problem in North China: Research and Perspective 被引量:12
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作者 XIA Jun LIU Meng-Yu JIA Shao-Feng 《Pedosphere》 SCIE CAS CSCD 2005年第5期563-575,共13页
This paper addresses the emergence of water security problems in North China with the aim of highlighting key waterresources management and water security issues for the long-term development of North China. Three key... This paper addresses the emergence of water security problems in North China with the aim of highlighting key waterresources management and water security issues for the long-term development of North China. Three key problemsrelated to water resources and security issues in North China in the 21st century are addressed, namely 1) the watercycle under environmental change, 2) agricultural water saving, and 3) water security. Development of internationalresearch related to these issues is also reviewed. The research plan developed recently by the Chinese Academy of Sciences(CAS) is discussed and suggestions on research and development of water resources science in North China are presented.Thanks to focus on experimental catchments and dedicated research stations, a detailed knowledge of the water cycle onNorth China farmland has been compiled. A range of techniques that include isotope tracers has been used to acquirehydrologic data. Much research has been devoted to developing distributed hydrological models at different scales. In thewell irrigation district, five different water saving irrigation regimes have been investigated, and these regimes have hadwidespread application, and reduced water use 60-150 mm while they increased water use efficiency (WUE) by 20%-30%.Furthermore, preventing water pollution is the most essential step to ensure North China’s water security. 展开更多
关键词 environmental change North China water cycle water resources water security
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Review of Rapid Transformation of Floodplain Wetlands in Northeast China: Roles of Human Development and Global Environmental Change 被引量:4
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作者 YU Xiaofei DING Shanshan +3 位作者 ZOU Yuanchun XUE Zhenshan LYU Xianguo WANG Guoping 《Chinese Geographical Science》 SCIE CSCD 2018年第4期654-664,共11页
Northeast China is the region with the largest area of wetlands in China. The Sanjiang Plain and the Songnen Plain are large freshwater marsh distribution regions that are affected by climate warming and by the increa... Northeast China is the region with the largest area of wetlands in China. The Sanjiang Plain and the Songnen Plain are large freshwater marsh distribution regions that are affected by climate warming and by the increasing frequency and density of extreme weather and are the regions most subject to disturbances by human activities in Northeast China. The wetlands of the Sanjiang Plain and the Songnen Plain have shrunk severely in the past 60 years, and wetland functions have been reduced substantially because of climate change, unreasonable land use, fire episodes, engineering and construction works and urbanization. Large-scale agricultural development started in the 1950 s has been the most important driving factor for wetland loss and degradation in the Sanjiang Plain. Water shortage has been the most important factor for degradation and fragmentation of wetlands in the Songnen Plain. To mitigate wetland degradation and better protect wetlands, special regulations, long-term mechanisms and technical support of wetland protection should be established. A wetland compensation program should be implemented, and technologies for increasing the adaptive capacity of wetlands should be developed. Moreover, it is most important to find the balanced threshold between agricultural development and wetland protection. 展开更多
关键词 WETLAND climate change human activities wetland recovery Sanjiang Plain Songnen Plain
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Historical Evolution of Mariculture in China During Past 40 Years and Its Impacts on Eco-environment 被引量:4
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作者 LIANG Yinxiu CHENG Xianwei +4 位作者 ZHU Hui Brian SHUTES YAN Baixing ZHOU Qingwei YU Xiangfei 《Chinese Geographical Science》 SCIE CSCD 2018年第3期363-373,共11页
The rapid development of mariculture in China in recent decades has satisfied people's demand of seafood, and has made a great contribution to economic development. However, mariculture has also caused some negati... The rapid development of mariculture in China in recent decades has satisfied people's demand of seafood, and has made a great contribution to economic development. However, mariculture has also caused some negative impacts on the eco-environment. By statistically analyzing national data(as well as data for four main provinces) regarding the mariculture area and cultivation species in China since reform and opening up, the historical evolution of mariculture during the past 40 years was analyzed, the driving factors related to policy, market and technology innovation were discussed, and the potential impacts of mariculture on the coastal eco-environment were also illustrated. The statistical results indicated that the maricultural area increased radically during the past 40 years, from 1979(116.47 × 10~3 ha) to 2012(2205.65 × 10~3 ha), with an increase of nearly 20-fold. Shandong Province represented the fastest-growing region, with an increase of 31-fold. Moreover, the cultivated species had gradually become diversified. Initially, shellfish and algae were major species, and then it developed to various species including fish, and currently shellfish and crustaceans were the major species. The development of mariculture was driven by government policies, market economy and technology innovation. Rapid development of mariculture also caused significantly adverse impacts on the eco-environment of the coastal regions. For example, the sea reclamation for mariculture decreased the area and function of coastal wetlands and the contaminants originating from mariculture destroyed the coastal aquatic environment. Fortunately, the implementation of ‘13 th Five-Year Fisheries Planning' is expected to help both improve the seafood quality and reduce the contamination in coastal aquatic environment. This current study will provide reference for management and structure adjustment of mariculture in the future. 展开更多
关键词 mariculture reclamation coastal wetlands aquatic environment pollution
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The Concept and Theoretical Implications of Carbon Emissions Rights Based on Individual Equity 被引量:1
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作者 Pan Jiahua Zheng Yan 《Chinese Journal of Population,Resources and Environment》 2011年第2期39-53,共15页
Climate change has become a hot topic in international environmental negotiations.For post-Kyoto international climate regime negotiations,many countries have proposed a variety of frameworks to share the emission red... Climate change has become a hot topic in international environmental negotiations.For post-Kyoto international climate regime negotiations,many countries have proposed a variety of frameworks to share the emission reduction responsibilities and allocate carbon emission rights,and have tried to quantify the emission reduction obligations of all countries based on the perspectives of international equity and individual equity.In this paper,the authors have distinguished the concepts of carbon emissions rights based on these two perspectives respectively,have analyzed the relationship between carbon emissions per capita and economic development,and have calculated and compared the proportion of cumulative emissions per capita of different countries in history and future,and then authors conclude that emission reduction obligations should be allocated based on each country's conditions,including historical emissions,development stage,and future demands.Developed countries should take the initiative to significantly reduce their emissions because they have already accomplished their industrialization process.However,developing countries are still in the process of industrialization,which requires more emission rights to meet their development needs.For China,the concept of carbon emissions based on individual equity can be used as a theoretical tool for the allocating the international carbon emissions rights. 展开更多
关键词 carbon emissions per capita cumulative carbon emissions per capita responsibility in mitigation basic needs for human development
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HISTORICAL DESERTIFICATION PROCESS IN HEXI CORRIDOR,CHINA 被引量:3
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作者 WANG Nai-ang ZHANG Chun-hui LI Gang CHENG Hong-yi 《Chinese Geographical Science》 SCIE CSCD 2005年第3期245-253,共9页
Over the last 2000 years, approximately 38 ancient cities were abandoned through desertification in Hexi Corridor, Northwest China. Among them, 21.05% were abandoned during the Northern and Southern Dynasties, 21.05% ... Over the last 2000 years, approximately 38 ancient cities were abandoned through desertification in Hexi Corridor, Northwest China. Among them, 21.05% were abandoned during the Northern and Southern Dynasties, 21.05% during the end of the Tang Dynasty and the Five Dynasties, and 57.9% during the Ming and Qing dynasties. At the same time, main lakes were shrinking rapidly from the 5th Century to the 6th Century and the end of the Qing Dynasty. The climate in these periods was relatively arid and cold with frequent dusts. The phase of these changes indicated that there were three periods of desertification enlargement in the northern China. They were Northern and Southern Dynasties, the end of Tang Dynasty and Five Dynasties, the Ming and Qing dynasties. The macro-process of desertification in the study area was controlled mainly by the climatic changes. But from the facts that the population density in the middle of Qing Dynasty had exceeded the critical index of population pressure in arid area and the usage rate of water resources had exceeded 40% in Hexi Corridor, this paper also suggests that human activities have played an important role in desertification processes of the study area mainly during the recent 300 years. 展开更多
关键词 historical desertification climate change human activities Hexi Corridor
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Temporal and spatial variations in the distribution of macroalgal communities along the Yantai coast, China 被引量:3
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作者 韩秋影 刘东艳 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第3期595-607,共13页
To explore the impact of environmental variables on macroalgal communities, their temporal and spatial distributions were examined along the Yantai coast, China between April 2010 and March 2011. Macroalgae sampling w... To explore the impact of environmental variables on macroalgal communities, their temporal and spatial distributions were examined along the Yantai coast, China between April 2010 and March 2011. Macroalgae sampling was conducted monthly at four sites along the coast: Jiahe River estuary, Zhifu Island, Fisherman's Wharf, and Yangma Island. The species composition and abundance, and their relationship with environmental variables were assessed. Along the Yantai coast, 35 macroalgae species were identifi ed, including 24 Rhodophyta spp., 7 Chlorophyta, and 4 Phaeophyta spp. Highest species numbers were recorded in the summer at all sampling sites, except in the Jiahe River estuary. Macroalgae biomass was the greatest in the summer. Year-round, the highest species number and dry biomass recorded at Fisherman's Wharf and Yangma Island was attributed to the substrate type. In summer, Ulva pertusa Kjellman was the dominant species identifi ed along the Yantai coast, which indicates a risk of macroalgae blooms. Our results show that seawater temperature and nutrients appear to signifi cantly affect the temporal and spatial patterns of macroalgal abundance along the Yantai coast. The effects of environmental variables on the macroalgae on the Yantai coast need further study. 展开更多
关键词 MACROALGAE temporal spatial INTERTIDAL NUTRIENT Yantai coast China
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Ecological Optimization Design Methods for the Green Space System in Densely Built-up Areas
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作者 BI Linglan ZHANG Fuwen ZHANG Fangming 《Journal of Landscape Research》 2018年第4期35-40,44,共7页
This paper is aimed at studying the environmental degradation of densely built-up areas in the process of urbanization in Qiina. In consideration of the severe environmental conditions of die densely built-up afeas, s... This paper is aimed at studying the environmental degradation of densely built-up areas in the process of urbanization in Qiina. In consideration of the severe environmental conditions of die densely built-up afeas, such as the lack of green space and. open space, ecological disturbance in some areas, poor landscape quality, this paper focused on the ecological space optimization in the process of urban renewal Firstly, theories related to this field were analyzed, and a comprehensive ecological efficiency evaluation sjrstem was established based on disciplines such as urban ecology, landscape ecology, urban sociology, behavioral psychology, biology, urban planning and design. Secondly, this system was used to judge the ecological efficiency of typical blocks on GIS platform and to find out the key spatial nodes that need to be updated. Thirdly, in different cases, space optimization projects witii different theories were designed, and the spatial model of influence was used to comprehensively evaluate their ecological efficiency. Finally, the parameters under different conditions were corrected to get a systematic system for evaluating the green space system in densely built-up areas* Due to the lack of undetstanding of the ecological fonction of green space in the past, die environmental condition of densely built-up areas is not good. Therefore, the most important task of urban oigauic renewal is ecological restoiation. In this paper, die exploiation is based on the reservation for built-up afeas to avoid repeated reconstruction and interference. Authors of this paper tried to find out a way to rebuild green space system that performed more complex functions with limited spatial resources. The application of “micfo-ttansfotmation” of green space system in densely built-up areas turns out to improve the quality of landscape while reducing the construction costrds 展开更多
关键词 Densely built-up area Gteen space system Ecological restoration Complex function Micto- cmation
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Identifying Scale-location Specific Control on Vegetation Distribution in Mountain-hill Region 被引量:3
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作者 QIU Bing-wen ZENG Can-ying +2 位作者 TANG Zheng-hong LI Wei-jiao Aaron HIRSH 《Journal of Mountain Science》 SCIE CSCD 2013年第4期541-552,共12页
vegetation continuous The scale-location specific control on distribution was investigated through wavelet transforms approaches in subtropical mountain-hill region, Fujian, China. The Normalized Difference Vegetatio... vegetation continuous The scale-location specific control on distribution was investigated through wavelet transforms approaches in subtropical mountain-hill region, Fujian, China. The Normalized Difference Vegetation Index (NDVI) was calculated as an indicator of vegetation greenness using Chinese Environmental Disaster Reduction Satellite images along latitudinal and longitudinal transects. Four scales of variations were identified from the local wavelet spectrum of NDVI, with much stronger wavelet variances observed at larger scales. The characteristic scale of vegetation distribution within mountainous and hilly regions in Southeast China was around 20 km. Significantly strong wavelet coherency was generally examined in regions with very diverse topography, typically characterized as small mountains and hills fractured by rivers and residents. The continuous wavelet based approaches provided valuable insight on the hierarchical structure and its corresponding characteristic scales of ecosystems, which might be applied in defining proper levels in multilevel models and optimal bandwidths in Geographically Weighted Regression. 展开更多
关键词 NDVI Continuous wavelet transform Characteristic scale Mountain-hill region Scale-location specific
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Response of rotifer community to environmental changes in five shallow lakes in the middle reach of Changjiang River, China 被引量:1
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作者 都雪 冯伟松 +4 位作者 李为 叶少文 刘家寿 张堂林 李钟杰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第5期1083-1091,共9页
We evaluated the response of a rotifer community to environmental changes in five shallow lakes in the middle reach of the Changjiang (Yangtze) River in summer and autumn 2010. These five lakes differed in trophic s... We evaluated the response of a rotifer community to environmental changes in five shallow lakes in the middle reach of the Changjiang (Yangtze) River in summer and autumn 2010. These five lakes differed in trophic status and rotifer community structure. Twenty-nine rotifer species were collected, of which Keratella cochlearis, Polyarthra dolichoptera, and Trichocerca elongate were dominant. The mean density, Shannon-Wiener diversity, and equitability among the five lakes differed significantly (P〈0.05). The mean rotifer density was positively correlated with trophic state. The diversity was higher in lakes with high macrophyte coverage. The composition of rotifer species was closely associated with the trophic gradient. Five environmental variables, Secchi depth, conductivity, TN, NHa-N, and TP, significantly affected the composition of rotifer species. Keratella quadrata, Brachionus calyciflorus, and B. forficula were more common in eutrophic conditions. Our results suggest that eutrophication has a significant influence on the rotifer community structure and highlight the potential for using rotifer community structure as an indicator of trophic status in subtropical lakes. 展开更多
关键词 ROTIFER environmental variables shallow lakes EUTROPHICATION
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Land Use/Cover Changes and Environmental Consequences in Songnen Plain,Northeast China 被引量:8
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作者 LIU Dianwei WANG Zongming +7 位作者 SONG Kaishan ZHANG Bai HU Liangjun HUANG Ni ZHANG Sumei LUO Ling ZHANG Chunhua JIANG Guangjia 《Chinese Geographical Science》 SCIE CSCD 2009年第4期299-305,共7页
The Songnen Plain in Northeast China,one of the key national bases of agricultural production,went through remarkable land use/cover changes in recent years.This study aimed to explore the long-term land use/cover cha... The Songnen Plain in Northeast China,one of the key national bases of agricultural production,went through remarkable land use/cover changes in recent years.This study aimed to explore the long-term land use/cover changes and the effects of these changes on the environment.The Landsat-based analysis showed that,during 1986-2000,cropland,built-up land and barren land had increased,among which cropland had the largest increase of 9,198km2 with an increase rate of 7.5%.Woodland,grassland,water body and swampland had decreased correspondingly,among which grassland had the most dramatic decrease of 6,127km2 with a decrease rate of 25.6%.The transition matrix results revealed that grassland,woodland and swampland were the three main land use types converted to cropland.Climate warming created the potential environment for the conversion of grassland and swampland into cropland.Land resources policy made by central and provincial governments of China affected the pattern and intensity of land use.Land use/cover changes accompanied by climatic variation brought out a series of environmental consequences,such as sand desertification of land,land salinization and alkalinization,grassland degradation,and more frequent floods.Under this circumstance,optimized land use structure and restoration measures are needed. 展开更多
关键词 land use change remote sensing sustainable development Songnen Plain China
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Sediment record of environmental change at Lake Lop Nur (Xinjiang, NW China) from 13.0 to 5.6 cal ka BP 被引量:1
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作者 汪敬忠 贾红娟 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第5期1070-1078,共9页
Lake Lop Nur is located in the eastern part of the Tarim Basin in Xinjiang,northwestern China.A 220-cm-long sediment core was collected from the center of the ear-shaped depression forming the basin and dated with AMS... Lake Lop Nur is located in the eastern part of the Tarim Basin in Xinjiang,northwestern China.A 220-cm-long sediment core was collected from the center of the ear-shaped depression forming the basin and dated with AMS^(14)C.Grain size,total organic matter(TOC),total nitrogen(TN),and TOC/TN(C/N)analyses were used to reconstruct climatic conditions from 13.0 to 5.6 cal ka BP.The results showed fi ve main climatic stages.Zone I(13.0–11.3 cal ka BP)was a wet–dry environment,whereas Zone II(11.3–8.9 cal ka BP)consisted of a primarily wet environment.Zone III(8.9–7.7 cal ka BP)was subdivided into Zone IIIa(8.9–8.2 cal ka BP)that indicated lake constriction and dry climate,and Zone IIIb(8.2–7.7 cal ka BP)in which the proxies indicated wet conditions.In Zone IV(7.7–6.6 cal ka BP),the climate presented a bit wet conditions.In Zone V(6.6–5.6 cal ka BP),abundant glauberite is present in the sediment and silt dominates the lithology;these results indicate the lake shrank and the overall climate was dry.Abrupt environmental events were also identifi ed,including six dry events at 11.0,10.5,9.3,8.6,8.2,and 7.6 cal ka BP and one fl ood event from 7.8 to 7.7 cal ka BP in the Early–Middle Holocene. 展开更多
关键词 sediment record environmental evolution abrupt environmental changing events Lop Nur northwestern China
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Optimization on the Conversion of Bamboo Shoot Shell to Levulinic Acid with Environmentally Benign Acidic Ionic Liquid and Response Surface Analysis 被引量:8
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作者 周存山 余筱洁 +2 位作者 马海乐 何荣海 Saritporn Vittayapadung 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第5期544-550,共7页
Levulinic acid(LA) has been identified as a promising green,biomass derived platform chemical.Response surface analysis(RSA) with a four-factor-five-level central composite design(CCD) was applied to optimize th... Levulinic acid(LA) has been identified as a promising green,biomass derived platform chemical.Response surface analysis(RSA) with a four-factor-five-level central composite design(CCD) was applied to optimize the hydrolysis conditions for the conversion of bamboo(Phyllostachys Praecox f.preveynalis) shoot shell(BSS) to LA catalyzed with ionic liquid [C4mim]HSO4.The effects of four main reaction parameters including temperature,time,C[C4mim]HSO4(initial [C4mim]HSO4 concentration) and XBSS(initial BSS intake) on the hydrolysis reaction for yield of LA were analyzed.A quadratic equation model for yield of LA was established and fitted to the data with an R2 of 0.9868,and effects of main factors and their corresponding relationships were obtained with RSA.Model validation and results of CCD showed good correspondence between actual and predicted values.The analysis of variance(ANOVA) of the results indicated that the yield of LA in the range studied was significantly(P&lt;0.05) affected by the four factors.The optimized reaction conditions were as follows:temperature of 145 ℃,time of 103.8 min,C[C4mim]HSO4 of 0.9 mol.L-1 and XBSS of 2.04%(by mass),respectively.A high yield [(71±0.41)%(by mol),triplicate experiment] was obtained at the optimum conditions of temperature of 145 ℃,time of 104 min,C[C4mim]HSO4 of 0.9 mol.L-1 and XBSS of 2%(by mass),which obtained from the real experiments,concurred with the model prediction [73.8%(by mol) based on available C6 sugars in BSS or 17.9%(by mass) based on the mass of BSS],indicating that the model was adequate for the hydrolysis process. 展开更多
关键词 levulinic acid ionic liquid response surface analysis bamboo shoot shell
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Scenario Formation of Energy Demand and CO_2 Emissionsfor Sustainable China
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作者 Wei Baoren Yagita Hiroshi 《Chinese Journal of Population,Resources and Environment》 北大核心 2008年第4期41-45,共5页
Co-integration theory has been employed in this paper and Granger causes are found between urbanization rate and GDP, between capital stock and GDP. Scenario analysis of GDP is performed using the GDP model establishe... Co-integration theory has been employed in this paper and Granger causes are found between urbanization rate and GDP, between capital stock and GDP. Scenario analysis of GDP is performed using the GDP model established in the paper. The energy consumptions in Germany, Japan and other developed countries are analyzed and compared with the energy consumption in China. Environmental friendly scenario of energy demand and CO2 emissions for sustainable China has been formed based on the results of comparison. Under environmental friendly scenario, the primary energy consumption will be 4.31 billion ton coal equivalence (tee) and CO2 emissions will be 1.854 billion t-c in 2050; energy per capital will be 3.06 tee that is 1.8 times of energy consumed in 2005 in China and 51% of consumed energy per capital in Japan in 2003. In 2050, the energy requirement of unit GDP will be 20% lower than that of Germany in 2003, but will be still 37% higher than that in Japan in 2003. It is certain that to fulfill the environmental friendly Scenario of energy demand and CO2 emissions is a difficult task and it needs long term efforts of the whole society, not only in production sectors but also in service and household sectors, 展开更多
关键词 energy demand CO2 emissions scenario analysis COINTEGRATION
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Physico-chemical Characteristics and Environmental Significance of Snow Deposition on Haxilegen Glacier No.51 in Tian Shan,China 被引量:2
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作者 DONG Zhiwen LI Zhongqin +2 位作者 ZHANG Mingjun WANG Feiteng WU Lihua 《Journal of Mountain Science》 SCIE CSCD 2011年第3期484-494,共11页
Snow chemistry on the glaciers of alpine regions is a good indicator of atmospheric environmental change.We examine snow chemistry in three snowpits at different altitudes on the Haxilegen Glacier No.51,in the Kuitun ... Snow chemistry on the glaciers of alpine regions is a good indicator of atmospheric environmental change.We examine snow chemistry in three snowpits at different altitudes on the Haxilegen Glacier No.51,in the Kuitun River source,Tian Shan,China,during July-September 2004 to 2007.We use correlation analysis,factor analysis and sea-salt tracing methods to examine the characteristics and sources of major ions and mineral dust particles in the snow.Results show that mineral dust particles and major ions in the snow pits vary seasonally.During the Asian dust period in springtime,the concentration of mineral dust particles and major ions deposited in snow is high,while the concentration is relatively low during the non-dust period of summer and autumn.This may be caused by dust storm activity in central Asia.The order of major ionic concentrations in the snow packs was determined to be Ca2+ > SO42-> NH4+ > NO3-> Cl-> Na+ > Mg2+ > K+.Ca2+ was the dominant cation;SO42- was the dominant anion.We find,with the exception of NO3-,that the variabilities of ionic concentrations are highly correlated.Results show that the glacier region was significantly affected by dust activity and anthropogenic source.The major ions,especially Na+,originate from dust sources of central Asia and from the Ocean,transported by the westerly winds. 展开更多
关键词 Snow chemistry Mineral dust Environmental significance Haxilegen glacier No. 51 Tian Shan
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Decadal variations in diatoms and dinoflagellates on the inner shelf of the East China Sea, China 被引量:1
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作者 Rediat ABATE 高亚辉 +4 位作者 陈长平 梁君荣 穆文华 Demeke KIFILE 陈杨航 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第6期1374-1386,共13页
Diatoms and dinoflagellates are two major groups ofphytoplankton that flourish in the oceans, particularly in coastal zone and upwelling systems, and their contrasting production have been reported in several world se... Diatoms and dinoflagellates are two major groups ofphytoplankton that flourish in the oceans, particularly in coastal zone and upwelling systems, and their contrasting production have been reported in several world seas. However, this information is not available in the coastal East China Sea (ECS). Thus, to investigate and compare the decadal trends in diatoms and dinoflagellates, a sediment core, 47-cm long, was collected from the coastal zone of the ECS. Sediment chlorophyll-a (Chl-a), phytoplankton-group specifc pigment signatures of diatoms and dinoflagellates, and diatom valve concentrations were determined. The sediment core covered the period from 1961 to 2011 AD. The chlorophyll-a contents ranged from 2.32 to 73 gg/g dry sediment (dw) and averaged 9.81 gg/g dw. Diatom absolute abundance ranged from 29 152 to 177 501 valve/gram (v/g) dw and averaged 72 137 v/g dw. Diatom valve and diatom specific pigment marker concentrations were not significantly correlated. Peridinin increased after the 1980s in line with intensified use of fertilizer and related increases in nutrient inputs into the marine environment. The increased occurrence of dinoflagellate dominance after the 1980s can be mostly explained by the increase in nutrients. However, the contribution of dinoflagellates to total phytoplankton production (Chl-a) decreased during the final decade of this study, probably because of the overwhelming increase in diatom production that corresponded with the construction of the Three Gorges Dam (TGD) and related light availability. Similarly, the mean ratio of fucoxanthin/peridinin for the period from 1982 to 2001 was 6% less than for 1961 to 1982, while the ratio for 2001 to 2011 was 45.3% greater than for 1982 to 2001. The decadal variation in the fucoxanthirdperidinin ratio implies that dinoflagellate production had been gradually increasing until 2001. We suggest that the observed changes can be explained by anthropogenic impacts, such as nutrient loading and dam construction. 展开更多
关键词 anthropogenic impact benthic diatoms pigment signature nutrient concentration Three Gorges Dam construction
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