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Do farmers care about climate change?Evidence from five major grain producing areas of China 预览
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作者 SONG Chun-xiao LIU Rui-feng +1 位作者 Les Oxley MA Heng-yun 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第6期1402-1414,共13页
Using a logistic model,this paper empirically investigated farmers’perception of climate change and its determinants based on a field survey of 1 350 rural households across five major grain producing provinces in Ch... Using a logistic model,this paper empirically investigated farmers’perception of climate change and its determinants based on a field survey of 1 350 rural households across five major grain producing provinces in China.The results show:i)There is an apparent difference in perception levels for long-term temperature and precipitation changes.Specifically,57.4%of farmers perceived the long-term temperature change correctly,but only 29.7%of farmers perceived the long-term precipitation change correctly;ii)The factors influencing the farmers’perceptions are almost completely different between precipitation and temperature,the former are mostly agriculture related,while latter are mostly non-agriculture related,except for farm size;and iii)Farmers are not expected to pay more attention to long-term precipitation changes over the crop growing seasons,because less than 30%of farmers can correctly perceive long-term precipitation change.Therefore,to improve the accuracy of farmers’perceptions of climate change,the government is recommended to:i)enhance education and training programs;ii)speed up land transfer and expand household land farm size;iii)develop farmer cooperative organizations;iv)invest more in agricultural infrastructure,specifically in major grain producing regions;and v)improve the agricultural environment and increase farming income. 展开更多
关键词 China major GRAIN producing areas determinants CLIMATE change PERCEPTION IRRIGATION areas
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Dynamic changes in lakes in the Hoh Xil region before and after the 2011 outburst of Zonag Lake
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作者 LIU Wen-hui XIE Chang-wei +6 位作者 ZHAO Lin WU Tong-hua WANG Wu ZHANG Yu-xin YANG Gui-qian ZHU Xiao-fan YUE Guang-yang 《山地科学学报:英文版》 SCIE CSCD 2019年第5期1098-1110,共13页
Zonag, Kusai, Hedin Noel and Yanhu Lakes are independent inland lakes in the Hoh Xil region on the Qinghai-Tibet Plateau. In September2011, Zonag Lake burst after the water level had increased for many years. Floods f... Zonag, Kusai, Hedin Noel and Yanhu Lakes are independent inland lakes in the Hoh Xil region on the Qinghai-Tibet Plateau. In September2011, Zonag Lake burst after the water level had increased for many years. Floods flowed through Kusai and Hedin Noel Lakes into Yanhu Lake;since then, the four small endorheic catchments merged into one larger catchment. This hydrological process caused the rapid shrinkage of Zonag Lake and continuous expansion of Yanhu Lake. In this study,based on satellite images, meteorological data and field investigations, we examined the dynamic changes in the four lakes and analyzed the influencing factors. The results showed that before 2011, the trends in the four lake areas were similar and displayed several stages. The change in the area of Zonag Lake corresponded well to the change in annual precipitation(AP), but the magnitude of the change was less than that of a non-glacier-fed lake. Although increased precipitation was the dominant factor that caused Zonag Lake to expand, increased glacier melting and permafrost thawing due to climate warming also had significant effects. After the 2011 outburst of Zonag Lake, due to the increasing AP and accelerating glacier melting, the increases in water volume of the three lakes were absorbed by Yanhu Lake, and Yanhu Lake expanded considerably. According to the rapid growth rates in water level and lake area, Yanhu Lake is likely to burst in 1-2 years. 展开更多
关键词 Dynamic CHANGE LAKE areas Influencing factors GLACIER CHANGE PERMAFROST thawing Zonag LAKE
A Geographical Analysis of Urban Sprawl in Abuja, Nigeria 预览
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作者 Susan Aniekwe Nwabueze Igu 《地理研究(英文)》 2019年第1期13-19,共7页
Urban sprawl is a challenge of the century across the globe;however its greatest impact is felt more in developing countries mainly due to its poor planning and ever increasing population. To ascertain how this affect... Urban sprawl is a challenge of the century across the globe;however its greatest impact is felt more in developing countries mainly due to its poor planning and ever increasing population. To ascertain how this affects a notable African city, Abuja, a questionnaire design was employed to elicit resident’s perception on the causes and effects of sprawl in the city. A principal component analysis was performed to simplify the relationship between large bodies of variables involved. This was able to collapse the 14 variables representing the causes of sprawl extracted from the response of the respondents and 9 variables representing the effects of sprawl on the environment and on the residents into significant and orthogonal components that explained the variables in the observed data. Among the nine factors that loaded highly on the components, population was the major factor discovered to be responsible for the sprawl. The analysis further showed the main effects of the sprawl on the city as: loss of biodiversity, high dependency on car, traffic congestion, land degradation, alteration of microclimate, destruction of aesthetics, increasing crime wave, pollution and waste management problems. Adhering to the guidelines on urban development for the city will help the residents not to be prone to the effects of urban sprawl and help to maintain good environmental standards and less spending on maintenance on the part of the government. 展开更多
关键词 BIODIVERSITY LOSS Land use change MIGRATION TROPICAL areas SUSTAINABLE development Urban
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A Study on Japanese Traditional Rice Production Technique in Warm Areas and Its Modern Ecological Value 预览
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作者 Lei YE Lulu QIAN 《亚洲农业研究:英文版》 2019年第1期38-41,共4页
Japanese traditional rice production technique features"sparse seeding,long cultivation,scattered planting and limited transplanting",and scientific rice production methods of deep plowing,fertilization,weed... Japanese traditional rice production technique features"sparse seeding,long cultivation,scattered planting and limited transplanting",and scientific rice production methods of deep plowing,fertilization,weeding,irrigation and drainage are employed.This technique has reversed the common practice of"dense seeding and planting"in rice paddies and changed the history of growing rice spikes purely out of stems,thus enabling stable and high yields of several tillering grain crops including rice.The technique can provide a useful reference for developing modern rice production in warm areas. 展开更多
关键词 Japan TRADITIONAL rice production TECHNIQUE in WARM areas SPARSE SEEDING and PLANTING Nougyou Zitoku
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Brief Study on Application of New Indoor Lawn in Northern Areas of China 预览
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作者 Yinghua LUO Shanmin QU +1 位作者 Xiangping LIU Chenghao JIN 《亚洲农业研究:英文版》 2019年第4期46-47,53共3页
At present,the development and function research of lawn has become diversified,and the application of lawn has been extended from outdoor to indoor environment. The indoor lawn has functions of absorbing toxic and ha... At present,the development and function research of lawn has become diversified,and the application of lawn has been extended from outdoor to indoor environment. The indoor lawn has functions of absorbing toxic and harmful gases,releasing oxygen,increasing air humidity and regulating temperature. It can effectively improve the indoor air quality of northern areas,purify and beautify the home environment.This paper elaborated the purpose and significance of the application of new indoor lawn,the establishment methods of the indoor lawn,and the application design of the indoor lawn landscape. 展开更多
关键词 NORTHERN areas of China INDOOR LAWN ENVIRONMENTAL PROTECTION
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The mechanism of farmland marginalization in Chinese mountainous areas:Evidence from cost and return changes
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作者 LI Shengfa LI Xiubin 《地理学报:英文版》 SCIE CSCD 2019年第4期531-548,共18页
Farmland marginalization has become the main trend of Iand-use change in the mountainous areas of China.Using annual survey data of major agricultural production costs and earnings at national and provincial levels in... Farmland marginalization has become the main trend of Iand-use change in the mountainous areas of China.Using annual survey data of major agricultural production costs and earnings at national and provincial levels in China,this study aims to analyze the reasons and mechanism behind farmland marginalization in mountainous areas.We find that farmers on plains are able to reduce their per mu labor input effectively through in tensive use of agricultural machinery,which has minimized the impact of the increase in labor price.However,it is extremely challenging for farmers in mountainous areas to use the same method owing to the rough terrain.Thus,per laborer farming area in these areas has increased relatively slowly,causing a widening gap in agricultural labor productivity between the two regions.With the rapid rise in labor costs since 2003,the marginalization of cultivated land in mountainous areas is evident.In 2013,the net profit of agricultural production in mountainous China fell below zero.Since 2000,the Iand-use and land?cover change in these areas was characterized by the reduction of farmland area,reforestation,and the enhancement of the NDVI value.The high correlation between the NDVI change rate and the ratio of change in farmland(r=-0.70)and forest(r=0.91)in mountainous areas at provincial level further attests to the trend of farmla nd margi nalization there.Fin ally,we summarize the mecha nism of such marginalization against the backdrop of the rapid increase in the opport unity cost of farming and the rapid fall of agricultural labor forces in mountainous areas.This study contributes to a deep understanding of the development process of farmland marginalization and abandonment as well as forest transition in Chinese mountainous areas. 展开更多
关键词 FARMLAND MARGINALIZATION FARMLAND ABANDONMENT LABOR COSTS returns agricultural LABOR PRODUCTIVITY mountainous areas China
Rapid Urban Land Expansion in Earthquake-Prone Areas of China
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作者 Qingxu Huang Shiting Meng +2 位作者 Chunyang He Yinyin Dou Qiang Zhang 《国际灾害风险科学学报:英文版》 CSCD 2019年第1期43-56,共14页
A timely understanding of urban expansion in earthquake-prone areas is crucial for earthquake risk assessment and urban planning for earthquake mitigation.However, a comprehensive evaluation of urban expansion in eart... A timely understanding of urban expansion in earthquake-prone areas is crucial for earthquake risk assessment and urban planning for earthquake mitigation.However, a comprehensive evaluation of urban expansion in earthquake-prone areas is lacking in China, especially in the context of rapid urbanization. Based on time series urban land data and seismic ground-motion parameter zonation maps, this study analyzed urban expansion in the most seismically hazardous areas(MSHAs) of China from1992 to 2015 on the national, regional, and city scales. The results show that urban land area in the MSHAs expanded by 6767 km~2 from 1992 to 2015, with a gain of 350%.Specifically, the increase in urban land area of small cities in the MSHAs of western China during this period was the fastest, 6.24 times greater than that at the national level. In terms of spatial patterns, the urban land patches in the MSHAs in 2015 were more fragmented than those in 1992 on all scales. The percentage of change in the number of patches and the landscape shape index of the urban land patches of small cities in the MSHAs of western China were the highest across all cities. Therefore, we believe that special attention should be paid to the cities in the MSHAs that exhibit the most rapid increases in both urban land area and fragmentation, especially the small cities in western China. It is imperative to integrate earthquake mitigation into the urban planning of these cities. 展开更多
关键词 China MOST seismically hazardous areas SEISMIC HAZARD exposure URBANIZATION URBAN expansion URBAN SUSTAINABILITY
Recovering threatened plant species and their habitats: The need for integrated action
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作者 Vernon H. Heywood 《植物多样性:英文版》 CAS CSCD 2019年第2期33-35,共3页
As an introduction to the Special Issue on the restoration of threatened plant species and their habitats, this ed让orial shows how the various papers in the issue address the range of in situ interventions involved i... As an introduction to the Special Issue on the restoration of threatened plant species and their habitats, this ed让orial shows how the various papers in the issue address the range of in situ interventions involved in species population management and restoration of their habitat, together with examples of case studies implementing these actions. It stresses the need for integrating these various interventions. It highlights the importance of protected areas in providing a degree of protection for threatened species but also the need to complement this with actions at the species level to ensure the effective conservation and long term persistence of these species. It emphasizes that ecological restoration is a complement to, not a substitute for conservation, and that the balanee of effort and allocation of resources between them is a key issue. 展开更多
关键词 THREATENED species management HABITAT RESTORATION In SITU conservation Protected areas
Conserving plants within and beyond protected areas-still problematic and future uncertain
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作者 Vernon H. Heywood 《植物多样性:英文版》 CAS CSCD 2019年第2期36-49,共14页
Against a background of continuing loss of biodiversity, it is argued that for the successful conservation of threatened plant species we need to ensure the more effective integration of the various conservation actio... Against a background of continuing loss of biodiversity, it is argued that for the successful conservation of threatened plant species we need to ensure the more effective integration of the various conservation actions employed, clarify the wording of the CBD targets and provide clearer operational guidance as to how they are to be implemented and their implementation monitored. The role and effectiveness of protected areas in conserving biodiversity and in particular plant species in situ are discussed as are rece nt proposals for a massive in crease of their exte nt. The need for much greater effort and investment in the conservation or protection of threatened species outside protected areas where most plant diversity occurs is highlighted. The difficulties involved in implementing effective in situ conservation of plant diversity both at an area- and species/population-based level are discussed. The widespread neglect of species recovery for plants is noted and the desirability of making a clearer distinction between species recovery and reintroduction is emphasized. Key messages from a global overview of species recovery are outlined and recommendations made, including the desirability of each country preparing a national species recovery strategy. The projected impacts of global change on protected areas and on species conservation and recovery, and ways of addressing them are discussed. 展开更多
关键词 Plant CONSERVATION CBD TARGETS Protected areas Species recovery CONSERVATION approaches
Site-Specific Zonation of Seismic Site Effects by Optimization of the Expert GIS-Based Geotechnical Information System for Western Coastal Urban Areas in South Korea
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作者 Han-Saem Kim Chang-Guk Sun Hyung-Ik Cho 《国际灾害风险科学学报:英文版》 CSCD 2019年第1期117-133,共17页
Earthquake-induced disasters are often more severe over soft soils than over firm soils or rocks owing to the seismic site effects related to the amplification of ground motion. On a regional scale, such differences c... Earthquake-induced disasters are often more severe over soft soils than over firm soils or rocks owing to the seismic site effects related to the amplification of ground motion. On a regional scale, such differences can be estimated by spatially predicting the subsurface soil thickness over the entire target area. Generally, soil deposits are deeper in coastal or riverside areas than in inland regions. In this study, the seismic site effects in the coastal metropolitan areas of Incheon and Bucheon, South Korea, were assessed to provide information on seismic hazards. Spatial prediction of geotechnical layers was performed for the entire study area within an advanced GIS framework. Approximately 7500 existing borehole records in the Incheon and Bucheon areas were gathered and archived into a GIS database. Surface geotechnical data were acquired from a walk-over survey. Based on the optimized geo-data, spatial zoning maps of site-specific seismic response parameters, based on multiscale geospatial modeling, were created and presented for use in a regional seismic mitigation strategy. Seismic zonation was also performed to determine site coefficients for seismic design over the entire target area and to compare them with each other. We verified that the geotechnical data based spatial zonation would be useful for seismic hazard mitigation. 展开更多
关键词 COASTAL urban areas Geodata Geostatistical spatial ZONATION SEISMIC SITE effects SITE classification South Korea
Operation management of green ports and shipping networks: overview and research opportunities
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作者 Lu ZHEN Dan ZHUGE +2 位作者 Liwen MURONG Ran YAN Shuaian WANG 《工程管理前沿:英文版》 2019年第2期152-162,共11页
Global ports and maritime shipping networks are important carriers for global supply chain networks, but they are also the main sources of energy consumption and pollution. To limit ship emissions in ports and offshor... Global ports and maritime shipping networks are important carriers for global supply chain networks, but they are also the main sources of energy consumption and pollution. To limit ship emissions in ports and offshore areas, the International Maritime Organization, as well as some countries, has issued a series of policies. This study highlights the importance and necessity of investigating emergent research problems in the operation management of green ports and maritime shipping networks. Considerable literature related to this topic is reviewed and discussed. Moreover, a comprehensive research framework on green port and shipping operation management is proposed for future research opportunities. The framework mainly comprises four research areas related to emission control and grading policies. This review may provide new ideas to the academia and industry practitioners for improving the performance and efficiency of the operation management of green ports and maritime shipping networks. 展开更多
关键词 MARITIME SHIPPING PORT operations green PORT green SHIPPING EMISSION control areas
Study on Differences in Procyanidine Content Between Muscat Hamburg Grape From Different Producing Areas 预览
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作者 Wen XU Qiusheng CHEN +4 位作者 Zhe YANG Qiang ZHANG Rui SUN Fang SU Yi PEI 《农业生物技术:英文版》 CAS 2019年第1期176-179,共4页
[Objectives]This study was conducted to analyze the differences in procyanidine content in grapes caused by different producing areas.[Methods]With Muscat Hamburg grape from different producing areas as an experimenta... [Objectives]This study was conducted to analyze the differences in procyanidine content in grapes caused by different producing areas.[Methods]With Muscat Hamburg grape from different producing areas as an experimental material,procyanidine content was determined by n-butanol-hydrochloric acid colorimetry.[Results]The procyanidins contents in different parts of the same variety ranked as grape seed >grape skin >grape flesh.The procyanidins contents in grapes from different producing areas were in order of Changli County,Hebei Province >Dazeshan Town,Shandong Province >Hangu District,Tianjin City.[Conclusions]The procyanidins contents in Muscat Hamburg grapes from different producing areas differ to a certain degree. 展开更多
关键词 Muscat Hamburg GRAPE PRODUCTION areas PROANTHOCYANIDINS DIFFERENCES
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Phenotypic plasticity of Artemisia ordosica seedlings in response to different levels of calcium carbonate in soil
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作者 XUE Pingping ZHAO Xuelai +1 位作者 GAO Yubao HE Xingdong 《干旱区科学:英文版》 SCIE CSCD 2019年第1期58-65,共8页
Plant phenotypic plasticity is a common feature that is crucial for explaining interspecific competition, dynamics and biological evolution of plant communities. In this study, we tested the effects of soil CaCO3(calc... Plant phenotypic plasticity is a common feature that is crucial for explaining interspecific competition, dynamics and biological evolution of plant communities. In this study, we tested the effects of soil CaCO3(calcium carbonate) on the phenotypic plasticity of a psammophyte, Artemisia ordosica, an important plant species on sandy lands in arid and semi-arid areas of China, by performing pot experiments under different CaCO3 contents with a two-factor randomized block design and two orthogonal designs. We analyzed the growth responses(including plant height, root length, shoot-leaf biomass and root biomass) of A. ordosica seedlings to different soil CaCO3 contents. The results revealed that, with a greater soil CaCO3 content, A. ordosica seedlings gradually grew more slowly, with their relative growth rates of plant height, root length, shoot-leaf biomass and root biomass all decreasing significantly. Root N/P ratios showed significant negative correlations with the relative growth rates of plant height, shoot-leaf biomass and root length of A. ordosica seedlings;however, the relative growth rate of root length increased significantly with the root P concentration increased, showing a positive correlation. These results demonstrate that soil CaCO3 reduces the local P availability in soil, which produces a non-adaptive phenotypic plasticity to A. ordosica seedlings. This study should prove useful for planning and promoting the restoration of damaged/degraded vegetation in arid and semi-arid areas of China. 展开更多
关键词 ARTEMISIA ORDOSICA N/P ratio PHENOTYPIC plasticity relative growth rate SOIL CaCO3 SOIL P availability ARID and SEMI-ARID areas
达萨瓦塔拉酒店:马拉萨萨罗瓦酒店,蒂鲁帕蒂,安得拉邦,印度 预览
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作者 什姆尔·贾瓦里·卡德里 萨利卡·沙缇 陈雨潇(译) 《世界建筑》 2019年第2期70-75,122共7页
蒂鲁玛拉-蒂鲁帕蒂寺庙是印度最受尊敬、最富有的寺庙,被认为是印度三位一体中三位至尊神之一的毗湿奴神的神圣住所。这里的宗教实践是虔诚的、仪式性的,怀有对神灵和庙宇习俗的极大信仰。每年有2000万虔诚的朝圣者拜访这座寺庙,需要有... 蒂鲁玛拉-蒂鲁帕蒂寺庙是印度最受尊敬、最富有的寺庙,被认为是印度三位一体中三位至尊神之一的毗湿奴神的神圣住所。这里的宗教实践是虔诚的、仪式性的,怀有对神灵和庙宇习俗的极大信仰。每年有2000万虔诚的朝圣者拜访这座寺庙,需要有序的人群管理。这个地区被认为是婚礼和庆祝活动的吉祥地,也适合那些喜欢将休闲会议和神圣的寺庙参观结合起来的有眼光的商务旅行者。 展开更多
关键词 习俗 酒店 庙宇 印度 地区 神圣 寺庙 仪式性
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A Study on Problems of Chinese-English Translation of Public Signs in Dazhou Based on the PRC National Standard 预览
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作者 SU Yan-fei 《美中外语:英文版》 2019年第2期82-90,共9页
Besides having a multitude of functions including prompting,directing,referring,and publicizing and the like,public sign shoulders the responsibility of building city image as well as reflecting a local government’s ... Besides having a multitude of functions including prompting,directing,referring,and publicizing and the like,public sign shoulders the responsibility of building city image as well as reflecting a local government’s capability of public service and governance,playing a critical role in improving city image,and strengthening soft power.Based on the People’s Republic of China National Standard:Guidelines for the Use of English in Public Service Areas,this paper studies the status quo of Chinese-English translation of public signs in downtown areas of Dazhou,a medium-sized city in eastern Sichuan,China,finding a variety of problems,such as understanding,grammar,wording,word-for-word translation,spelling,and so forth;meanwhile,this paper provides suggestions about translation of public signs and revised translation for reference in order to improve translation quality. 展开更多
关键词 Dazhou PUBLIC SIGNS Chinese-English translation the PRC National Standard: Guidelines for the Use of ENGLISH in PUBLIC Service Areas
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Valuable Lessons Learned 预览
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作者 HUANG CHENGWEI 《今日中国:英文版》 2019年第3期60-62,共3页
LOCATED in the east of central China’s Henan Province,Lankao County has 13 towns,three residential communities,and 450 administrative villages under its jurisdiction.It has a total area of 1,116 square km and a total... LOCATED in the east of central China’s Henan Province,Lankao County has 13 towns,three residential communities,and 450 administrative villages under its jurisdiction.It has a total area of 1,116 square km and a total population of 850,000,among which 772,900 are from rural areas.The county was identified as a key county in the national development-oriented poverty alleviation campaign in 2002,and included in the contiguous destitute region of the Dabie Mountains in 2011. 展开更多
关键词 DABIE MOUNTAINS LOCATED Destitute areas
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Keywords to Understand China
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《中国与非洲:英文版》 2019年第2期30-31,共2页
Keywords are one of the best ways to understand a country.In China,with the rapid development in different areas,the keywords keep changing.ChinAfrica presents a selection of prevailing keywords to help readers unders... Keywords are one of the best ways to understand a country.In China,with the rapid development in different areas,the keywords keep changing.ChinAfrica presents a selection of prevailing keywords to help readers understand China better. 展开更多
关键词 UNDERSTAND China RAPID DEVELOPMENT DIFFERENT areas
Design of Landscape Ecological Restoration for"Five Mining Areas"of the Laoqing Mountain in the Dianchi Lake Basin 预览
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作者 ZHU Guofei HU Yeqing +2 位作者 LONG Haijun CAI Fang SHE Lihua 《景观研究:英文版》 2019年第2期95-98,103共5页
Through analyzing basic conditions of the “five mining areas” in the Laoqing Mountain of the Dianchi Lake Basin, in Kunming City, South China, the ecological restoration design of “integrating engineering protectio... Through analyzing basic conditions of the “five mining areas” in the Laoqing Mountain of the Dianchi Lake Basin, in Kunming City, South China, the ecological restoration design of “integrating engineering protection and biological restoration, building the landscape ecological security pattern of the Laoqing Mountain” was proposed. Considering the different ecological functional areas, varying engineering measures, greening patterns, and irrigation means were selected for the ecological restoration, including site management, vegetation restoration, management and utilization etc.. These ecological restoration measures will produce favorable ecological benefits, and also take landscape effect and sustainable development into consideration, which will contribute to the ecological restoration of the “five mining areas”, and provide a scientific and feasible reference for the ecological restoration in China. 展开更多
关键词 "Five mining areas" of Laoqingshan MOUNTAIN LANDSCAPE ECOLOGICAL RESTORATION Site MANAGEMENT VEGETATION RESTORATION MANAGEMENT and utilization
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大数据时代背景下的物联网应用技能实现 预览
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作者 李泰 《长沙大学学报》 2018年第2期36-38,共3页
信息化科技水平的不断提升,推动着物联网技术的飞速发展.物联网技术不仅深入到我们的生活,而且改变着我们的生活.从社会生活、医疗卫生、地质信息化、物流这四个领域对大数据时代背景下的物联网应用技能进行分析和探究.
关键词 大数据 物联网 应用技能 领域
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Optimization of Shanghai Marine Environmental Monitoring Sites in the Identification of Boundaries of Different Water Quality Grades 预览
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作者 FAN Haimei GAO Bingbo +4 位作者 WANG Jinfeng QIN Xiaoguang LIU Pengxia HU Maogui XU Peng 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2018年第4期846-854,共9页
Water quality is critical to ensure that marine resources and the environment are utilized in a sustainable manner. The objective of this study is therefore to investigate the optimum placement of marine environmental... Water quality is critical to ensure that marine resources and the environment are utilized in a sustainable manner. The objective of this study is therefore to investigate the optimum placement of marine environmental monitoring sites to monitor water quality in Shanghai, China. To improve the mapping or estimation accuracy of the areas with different water quality grades, the monitoring sites were fixed in transition bands between areas of different grades rather than in other positions. Following bidirectional optimization method, first, 18 candidate sites were selected by filtering out specific site categories. Second, three of these were, in turn, eliminated because of the rule defined by the changes in the areas of water quality grades and by the standard deviation of the interpolation errors of dissolved inorganic nitrogen(DIN) and phosphate(PO_4-P). Furthermore, indicator kriging was employed to depict the transition bands between different water quality grades whenever new sampling sites were added. The four optimization projects of the newly added sites reveal that, all optimized sites were distributed in the transition bands of different water grades, and at the same time in the areas where the historical sites were sparsely distributed. New sites were also found in the overlap region of different transition bands. Additional sites were especially required in these regions to discriminate the boundaries of different water quality grades. Using the bidirectional optimization method of the monitoring sites, the boundaries of different water quality grades could be determined with a higher precision. As a result, the interpolation errors of DIN and PO_4-P could theoretically decrease. 展开更多
关键词 BIDIRECTIONAL OPTIMIZATION method boundaries of water quality GRADES CHANGJIANG River ESTUARY and its adjacent areas transition bands indicator kriging
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