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An overview of the resources and environment conditions and major geological problems in the Yangtze River economic zone, China 被引量:6
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作者 Yue-hua Jiang Liang-jun Lin +16 位作者 Li-de Chen Hua-yong Ni Wei-ya Ge Hang-xin Cheng Gang-yi Zhai Gui-ling Wang Yi-zhong Ban Yuan Li Ming-tang Lei Cheng-xuan Tan Jing-wen Su Quan-ping Zhou Tai-li Zhang Yun Li Hong-ying Liu Ke Peng Han-mei Wang 《China Geology》 2018年第3期435-449,共15页
Focusing on the Yangtze River economic zone,the previous geological researches are systematically summarized,resources and environment conditions and major geological problems which are needing to be concerned in land... Focusing on the Yangtze River economic zone,the previous geological researches are systematically summarized,resources and environment conditions and major geological problems which are needing to be concerned in land planning and construction are studied.The results show that the resource conditions of cultivated land,shale gas,geotherm,lithium and so on are superior in the Yangtze River economic zone,and the resources and environment conditions are conducive to develop the modern agriculture,clean energy industry and strategic emerging industries.3×1013 m^2 farmlands without heavy metal pollution are concentrated;there are three national level shale gas exploration and development bases with explored reserves of 5.441×1011 m^3;geothermal availability is 2.4×109 t of standard coal each year,equivalent to 19% of the amount of coal in 2014;Asia's largest energy lithium metal ore deposit is found.In some parts of Yangtze River economic zone,there are some major geological problems such as active faults,karst collapse,ground subsidence,landslide-collapse-debris flow,affecting the river-crossing channels,high-speed railway,urban agglomeration and green ecological corridor planning and construction.Those problems should be concerned,and the relevant suggestions and countermeasures are put forward.Meanwhile,the ideas to further support the development of the Yangtze River economic zone are put forward. 展开更多
关键词 the yangtze river economic zone Resources and environment CONDITIONS MAJOR geological problems Environmental GEOLOGY HYDROGEOLOGY Disaster GEOLOGY
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Possible effect of climate changes on the coastal zone of the Yangtze River Delta
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作者 Miao Qilong Nanjing Institute of Meteorology, Nanjing 210044, CHINA 《Journal of Geographical Sciences》 SCIE CSCD 1998年第1期42-51,共10页
A coastal historical evolution of the Yangtze River Delta was discussed in this paper on the basis of the historical data of the coastal zone and an estimation was made for the future change of the coast The emphasi... A coastal historical evolution of the Yangtze River Delta was discussed in this paper on the basis of the historical data of the coastal zone and an estimation was made for the future change of the coast The emphasis was put on the future climate change that will have influence on the sea wall, coastal navigation and freshwater resources in the Delta It was also pointed out that the global warming and precipitation increase in the Yangtze River Valley may exert more impact on the zone In addition, some measures describing how to adapt to the climate change and reduce its impact were put forward 展开更多
关键词 climate change greenhouse effect sea surface rising the yangtze river Delta coastal zone
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Research on the Seismic Activity of the Lower Yangtze River-South Yellow Sea Seismic Zone
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作者 Xie Zhuojuan Lv Yuejun +2 位作者 Peng Yanju Lan Jingyan Zhang Lifang 《Earthquake Research in China》 2013年第2期178-190,共13页
The Lower Yangtze River-South Yellow Sea Seismic Zone,located at the southeast of the Northern China Seismic Zone, characterized by moderate-strong earthquakes, is an intensive earthquake zone,which is controlled by a... The Lower Yangtze River-South Yellow Sea Seismic Zone,located at the southeast of the Northern China Seismic Zone, characterized by moderate-strong earthquakes, is an intensive earthquake zone,which is controlled by a series of faults within the Lower Yangtze River-South Yellow Sea Seismic Zone. This article counts and calculates the bvalue,V 4 and energy density value of medium-small earthquakes by taking full advantage of the latest data from regional seismic stations,reviews data of historical earthquakes and seismic structure,and discusses the relationship between spatial distribution of the b-value, historical strong earthquakes and spatial distribution of energy density of medium-small earthquakes,and further investigates the seismic activity of the Lower Yangtze River- South Yellow Sea Seismic Zone. This article obtains seismic activity parameters of the Lower Yangtze River-South Yellow Sea Seismic Zone as calculation parameters for probabilistic seismic hazard analysis,and discusses the trend of this seismic zone in the next one hundred years and deduces the potential seismic hazard region within this seismic zone,which provides references and methods for long-term prediction on seismic activity. The research results are significant to seismic zoning, seismic safety evaluation of engineering sites and long-term prediction of seismic activity. 展开更多
关键词 地震活动性参数 长江下游 地震带 南黄海 概率地震危险性分析 地震安全性评价 长江中下游 中国北方地区
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Distribution and Controlling Factors of Dissolved Gaseous Mercury and Reactive Mercury in Seawater Near Yangtze River Estuary
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作者 YIN Pingping ZHENG Wen +4 位作者 WANG Yan LIU Ruhai HE Xin SUN Haolin LI Dou 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第5期1341-1352,共12页
Complex hydrocultural conditions in the estuary affect the migration and transformation of mercury.Using two voyages in July and October 2018,Dissolved Gaseous Mercury(DGM)and Reactive Mercury(RHg)were determined to e... Complex hydrocultural conditions in the estuary affect the migration and transformation of mercury.Using two voyages in July and October 2018,Dissolved Gaseous Mercury(DGM)and Reactive Mercury(RHg)were determined to explore the source,transformation and influence of DGM content in the adjacent waters of Yangtze River Estuary in summer and autumn.The results showed the contents of DGM and RHg in summer were higher than those in autumn,and both of them were higher than those in open sea.In summer and autumn,the Yangtze River brought a higher concentration of DGM,and different flow direction and runoff resulted in differences in the high value region of the surface.The emergence of low-oxygen zones in summer was conducive to the production of DGM.In autumn,windy weather allowed seawater disturbances to promote the release of mercury from the underlying sediments,especially in shallow sea in northwest.RHg showed a higher concentration in the offshore than in the open sea in summer,but there was no such trend in autumn,reflecting the influence of less runoff input.DGM is the main product of RHg reduction,and there was a significant positive correlation between DGM and RHg in summer(r=0.356,P<0.05),while the correlation between DGM and RHg was not significant in autumn due to the influence of light intensity,wind speed and nutrients.The exchange flux of mercury in the adjacent waters of the Yangtze River Estuary was higher than that in the open sea.There was no significant difference of the release flux of mercury in summer and autumn.This article highlighted that the input of mercury from the Yangtze River runoff promotes the release of mercury in seawater,and the hypoxic zone caused by eutrophication is conducive to the production of DGM. 展开更多
关键词 yangtze river Estuary dissolved gaseous mercury reactive mercury exchange flux hypoxic zone
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Malaria Transmission Potential in the Three Gorges Reservoir of the Yangtze River, China 被引量:1
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作者 WANG Duo Quan TANG Lin Hua +2 位作者 GU Zhen Cheng ZHENG Xiang JIANG Wei Kang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第1期54-62,共9页
Objective To define and evaluate the malaria transmission potential in the Yangtze River, following construction of the Three Gorges Reservoir. Methods Six villages, namely, Kaixian, Fengjie, Wanzhou, Fuling, Yubei, a... Objective To define and evaluate the malaria transmission potential in the Yangtze River, following construction of the Three Gorges Reservoir. Methods Six villages, namely, Kaixian, Fengjie, Wanzhou, Fuling, Yubei, and Zigui were selected for investigating the malaria transmission potential in the reservoir. Transmission potential was estimated by mathematical modeling and evaluation of the local malaria situation. Factors that influenced the transmission potential were analyzed using Poisson regression analysis in combination with Grey Systematic Theory (based on evaluation by the Delphi method). Results Indirect fluorescent antibody data and the incidence of malaria in the local population were consistent with the malaria transmission potential calculated for the area. Multivariate Poisson regression analysis showed a statistically significant association between the riparian zone and the man‐biting rate. Conclusion The risk of a malaria epidemic can be forecasted using the malaria transmission potential parameters investigated here which was closely correlated with the riparian zone. 展开更多
关键词 MALARIA Transmission potential yangtze river Three Gorges Reservoir riparian zone
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Land-Use Changes and Human Driving in and Near the Yangtze River Delta from 1995–2015 被引量:1
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作者 LI Meina YIN Ping +3 位作者 DUAN Xiaoyong LIU Jinqing QIU Jiandong PHUNG Van Phach 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第6期1361-1368,共8页
We analyzed the characteristics and trends of land-use change in and near the coastal zone of the Yangtze River Delta(YRD) during five periods(1995, 2000 2005, 2010, and 2015) using remotely sensed Landsat imagery. Us... We analyzed the characteristics and trends of land-use change in and near the coastal zone of the Yangtze River Delta(YRD) during five periods(1995, 2000 2005, 2010, and 2015) using remotely sensed Landsat imagery. Using automatic supervised classification combined with visual interpretation, we obtained land-use information for five study areas(Nantong, Shanghai, Jiaxing, Ningbo, and Zhoushan). Significant land-use changes have occurred in this area between 1995 and 2015, characterized in particular by large reductions in cultivated land and rapid increases in urbanized land. In addition, land reclamation was very active in this period as an effective supplement to the increased demand for land development: since 1995, 1622 km^2 of land was reclaimed from near-coastal regions in the study area. This increase in urbanization was jointly driven by population, economic, transportation, and policy factors. Urban areas expanded from the center outward in concentric rings, with infrastructure guiding the radial expansion of development along transportation corridors, thus forming a network of connections. Due to the influence of national land regulation policies, the expansion rate of development in the YRD gradually diminished after 2010. This indicates that the area's resource and environmental carrying capacity has reached a saturation stage in which urbanization has transitioned from broad and incremental expansion to the intensive use of land resources. 展开更多
关键词 LAND use COASTAL zone yangtze river DELTA land-use change remote sensing technology RECLAMATION driving mechanisms
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黄河中下游过渡区河岸植物多样性与土壤因子的关系
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作者 梁少民 吕宇豪 +1 位作者 李雅 吕金岭 《西北植物学报》 CAS CSCD 北大核心 2024年第6期968-976,共9页
[目的]河岸带物种多样性与土壤因子的关系对维持河岸带生态系统的稳定性十分重要,为揭示黄河中下游河岸带物种多样性与土壤因子的关系,进一步为黄河中下游过渡区河岸生态恢复、保护和高质量发展提供一定的参考与理论指导。[方法]采用样... [目的]河岸带物种多样性与土壤因子的关系对维持河岸带生态系统的稳定性十分重要,为揭示黄河中下游河岸带物种多样性与土壤因子的关系,进一步为黄河中下游过渡区河岸生态恢复、保护和高质量发展提供一定的参考与理论指导。[方法]采用样方调查法、试验分析法、CCA排序法等方法,以河南黄河中下游过渡区对植物分布和物种多样性与土壤因子的关系进行研究。[结果](1)黄河中下游过渡区河岸有机质、速效钾及有效磷均属于中等变异程度,土壤含水量、全氮变异系数为强变异性,土壤养分空间分布总体呈现中度不均匀的特征。(2)黄河中下游过渡区河岸植物优势度指数(D)与土壤全氮具有显著负相关关系(P<0.05);土壤pH值、速效钾和有效磷对物种丰富度指数(S)的影响不明显;均匀度指数(E)、香农-威纳指数(H)与6个土壤因子之间均没有达到显著水平。(3)红蓼、头状穗莎草、长芒稗、糠稷、醴肠群落的分布受土壤含水量的影响较大;青蒿、酸枣、毛白杨等的分布主要受全氮的影响较大,在全氮含量较高的区域分布较多;葎草和反枝苋受速效钾影响较大;而狗牙根、苍耳、芦苇、狗尾草、春蓼、绿豆等群落受土壤因子的影响较小。[结论]黄河中下游过渡区河岸带土壤含水量、速效钾及全氮是影响植物分布的主要因子,不同植物对土壤条件的需求存在差异,能够直观反映出植被与土壤环境之间的关系。 展开更多
关键词 黄河中下游过渡区 河岸带 植物群落 物种多样性 土壤因子
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新能源汽车产业集聚对区域绿色经济效率的影响——基于长江经济带的实证研究
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作者 杨恺钧 曹安琪 方慈慧 《资源与产业》 2024年第1期35-49,共15页
将产业集聚、绿色技术创新和绿色经济效率纳入同一研究框架,聚焦长江经济带,研究新能源汽车产业集聚对绿色经济效率的影响,为我国在“双碳”背景下推进实现制造强国的战略目标及长江经济带新能源汽车发展提供参考。论文基于2012—2020... 将产业集聚、绿色技术创新和绿色经济效率纳入同一研究框架,聚焦长江经济带,研究新能源汽车产业集聚对绿色经济效率的影响,为我国在“双碳”背景下推进实现制造强国的战略目标及长江经济带新能源汽车发展提供参考。论文基于2012—2020年长江经济带沿线11个省市面板数据,综合利用超效率SBM和区位熵法,构建计量模型,实证研究新能源汽车产业集聚对绿色经济效率的影响,探讨绿色技术创新的中介效应,并进一步分析新能源汽车产业集聚对绿色经济效率的空间溢出效应和区域异质性。研究结果表明:1)长江经济带整个区域已形成“带状”新能源汽车产业集聚区,集聚平均水平随年份波动上升,上中下游产业集聚水平呈递增格局,水平差异较大且有逐渐增加趋势;2)新能源汽车产业集聚通过整合内部网络资源和提升外部整体能力,对长江经济带绿色经济效率具有正向促进作用;3)产业集聚的发展通过竞争效应和合作效应促进绿色技术创新,而绿色技术创新的发展可以提升经济动力和效率,因而绿色技术创新在产业集聚与绿色经济效率之间具有中介作用;4)新能源汽车产业集聚对绿色经济效率具有空间溢出效应,上中下游新能源汽车产业集聚对绿色经济效率的影响存在差异。据此,从加强产业集群建设,发挥新能源汽车产业发展的长效机制、强化发展绿色技术创新体系和推动新能源汽车区域异质性发展三个方面提出对策建议。 展开更多
关键词 新能源汽车 产业集聚 绿色经济效率 绿色技术创新 长江经济带
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区域协作治理中的领导力:一个动态分析框架——以长三角生态绿色一体化发展示范区为例
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作者 邢华 冯博 《苏州大学学报(哲学社会科学版)》 北大核心 2024年第1期20-32,共13页
区域协作治理是当前公共管理研究的热点话题,将领导力理论嵌入区域协作治理场域中可以为理解复杂的协作过程提供动态视角。本文基于相关理论构建了由公共价值、运行系统、领导活动组成的区域协作治理领导力要素模型,其中公共价值是区域... 区域协作治理是当前公共管理研究的热点话题,将领导力理论嵌入区域协作治理场域中可以为理解复杂的协作过程提供动态视角。本文基于相关理论构建了由公共价值、运行系统、领导活动组成的区域协作治理领导力要素模型,其中公共价值是区域协作治理领导力的出发点和落脚点,运行系统由结构管理、过程管理、政治管理构成,是区域协作治理领导力的核心要素,领导活动是区域协作治理中正式领导和非正式领导的行为方式;本文以长三角生态绿色一体化发展示范区为例印证并发掘领导力的动态过程,认为示范区塑造了国家战略引领的公共价值体系,构建了以网络行政组织(NAO)为核心的复杂运行系统,形成了关系导向的领导策略和行动逻辑,通过这些领导力要素整合提升了示范区协作治理绩效;基于案例研究凝练搭建了区域协作治理领导力的动态分析框架,并提出长三角示范区加快从区域项目协同走向区域一体化制度创新的对策建议。 展开更多
关键词 区域协作治理 领导力 公共价值 长三角示范区
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缓冲带植被模式对河岸土壤稳定性的影响
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作者 张鸿龄 唐雪寒 王斅誉 《沈阳大学学报(自然科学版)》 CAS 2024年第1期18-27,共10页
通过10年辽河保护区河岸植被缓冲带工程实施,研究了河岸带不同植被模式对于河岸土壤团聚体组成、结构、土壤稳定性、抗蚀性的影响。结果表明,河岸土壤粒径组成为砂粒质量分数为58%~68%,粉粒质量分数为30%~40%。土壤有机质质量分数为12.0... 通过10年辽河保护区河岸植被缓冲带工程实施,研究了河岸带不同植被模式对于河岸土壤团聚体组成、结构、土壤稳定性、抗蚀性的影响。结果表明,河岸土壤粒径组成为砂粒质量分数为58%~68%,粉粒质量分数为30%~40%。土壤有机质质量分数为12.0~28.1 g·kg^(-1),与植被种植前相比,灌草、乔草缓冲带河岸土壤有机质含量明显增加。相比于干筛法,湿筛后水稳性团聚体的主要粒径组成为0.25~0.50 mm,占比14%~25%,粒级直径>0.5 mm土壤水稳性团聚体占比明显下降,而粒级直径为0.25~0.50 mm的土壤水稳性团聚体占比明显增加。杞柳缓冲带和水蜡缓冲带土壤结构、团聚体稳定性和抗蚀性高于其他植被带。 展开更多
关键词 辽河保护区 河岸缓冲带 植被模式 土壤团聚体 土壤抗蚀性指标
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Regional eco-efficiency evaluation and spatial pattern analysis of the Yangtze River Economic Zone 被引量:8
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作者 HA Lin TU Jianjun +5 位作者 YANG Jianping XU Chunhai PANG Jiaxing LU Debin YAO Zuolin ZHAO Wenyu 《Journal of Geographical Sciences》 SCIE CSCD 2020年第7期1117-1139,共23页
The environmental ecology of the Yangtze River Economic Zone(YREZ)faces ecological function decline,deterioration and degradation under intense human activities,long-term development and utilization and its economy ha... The environmental ecology of the Yangtze River Economic Zone(YREZ)faces ecological function decline,deterioration and degradation under intense human activities,long-term development and utilization and its economy has developed rapidly over recent decades.Eco-efficiency is considered as a measure of coordinated development of economy,resources,environment and ecology,and is currently considered a very important issue.In this paper,based on the slack-based measure and data envelope analysis model,we take 129 prefecture-level cities of the YREZ as the study unit and measure the eco-efficiency of the YREZ in 2000,2005,2010 and 2015,which considers undesired output.The evaluation of the status quo of the regional eco-efficiency development was carried out at provincial,prefectural and city scales.The spatial autocorrelation test model and standard deviation ellipse were used to analyze the spatially distributed characteristics and the evolutionary regularity of eco-efficiency.Our study suggested that the eco-efficiency value varied significantly at different spatiotemporal scales and the overall distribution presented an"N-shaped"pattern,the value is the largest downstream and the smallest upstream.Regional eco-efficiency presented certain volatility in growth and a clear spatial positive agglomeration trend from 2000 to 2015.The spatial distribution of each agglomeration area was also significantly different,forming some high-high agglomeration areas at the center of the shaft with Shanghai and surrounding cities,and some low-low agglomeration areas at the center with middle reaches and upstream cities.The low-high over-aggregation and high-low polarization clusters were fewer.At the same time,with the change of the research period,the degree of positive agglomeration became increasingly pronounced and the eco-efficiency gap of the neighborhoodunit reduced.The regional eco-efficiency value of the YREZ presented a spatial distribution pattern in the northeast-southwest axis and the evolutionary pattern of the regional eco-efficiency similarly showed a northeast-southwest orientation. 展开更多
关键词 ECO-EFFICIENCY SBM-DEA model undesired output yangtze river Economic zone
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长江经济带国土空间格局与功能演变的时空特征和响应过程 被引量:1
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作者 林树高 诸培新 +3 位作者 陆汝成 陈昌玲 毕佳港 罗金玲 《农业工程学报》 EI CAS CSCD 北大核心 2024年第4期304-316,共13页
揭示国土空间格局与功能演变的内在机制对缓解国土空间冲突具有现实意义。在探讨国土空间格局与功能交互机制的基础上,采用地学图谱、核密度估计等模型分析2000—2020年长江经济带国土空间格局与功能演变的时空特征,借助双变量空间自相... 揭示国土空间格局与功能演变的内在机制对缓解国土空间冲突具有现实意义。在探讨国土空间格局与功能交互机制的基础上,采用地学图谱、核密度估计等模型分析2000—2020年长江经济带国土空间格局与功能演变的时空特征,借助双变量空间自相关模型识别国土空间格局与功能演变的响应过程。结果表明:1)长江经济带20 a内城镇空间扩张29559.54 km^(2),迫使农业空间与生态空间分别减少25162.63、3268.36 km^(2),农业空间与生态空间互换及其内部结构重组主导国土空间格局演变过程,国土空间格局演变速度呈现上游快于中游快于下游的地域分异规律。2)长江经济带城镇、农业和生态功能均值分别由0.129、0.287、0.646提升至0.343、0.456、0.698,中、下游地区国土空间功能发展由城镇功能拉动、农业功能推动,上游地区国土空间功能发展由生态功能主导、农业功能抬升,国土空间功能演变强度具有下游高于中游高于上游的区域差异特征。3)国土空间格局与功能演变具有双向非线性响应关系,城镇空间扩张与其功能扩容呈现“双增”的空间正相关性,农业、生态空间收缩与其功能提质呈现“一减一增”的空间负相关性,上、下游国土空间格局与功能演变的响应程度较高,中游地区因面临上游地区城镇、农业功能的虹吸效应和下游地区生态功能的溢出效应,响应程度较低。应以国土空间功能提质、增效、扩容为导向,形成互补、融合、协调的城镇空间开发、农业空间保护、生态空间修复的国土空间格局,促进长江经济带可持续均衡发展。 展开更多
关键词 国土空间 "三区空间" 格局演变 功能演变 响应过程 长江经济带
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长三角合作共建园区转型路径与机制——基于“同质多形”视角 被引量:1
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作者 杨凌凡 罗小龙 +2 位作者 唐蜜 丁子尧 顾宗倪 《地理科学》 CSCD 北大核心 2024年第3期379-390,共12页
合作共建园区的转型发展作为重要区域治理现象在学术界备受关注。本文采用半结构化访谈法和文本分析法,援引“同质多形”理论视角并构建研究框架,尝试从尺度、网络、领域等多个维度揭示长三角合作共建园区转型的内在动力及其新发展趋势... 合作共建园区的转型发展作为重要区域治理现象在学术界备受关注。本文采用半结构化访谈法和文本分析法,援引“同质多形”理论视角并构建研究框架,尝试从尺度、网络、领域等多个维度揭示长三角合作共建园区转型的内在动力及其新发展趋势。研究发现:①长三角合作共建园区多维特征处于动态演化中,资本需求与行政治理困境共同构成最为关键的演化动力。园区经历了以企业转移为目标的早期形成阶段、2010年后的波折发展阶段以及2016年后以多元伙伴议程为导向的创新转型阶段,园区的转型发展由不同时期经济发展需求与行政治理困境共同推动。②长三角合作共建园区治理方式从政府间协同转向多元主体网络行动,使园区的尺度、网络、领域特征从早期迁出地主导的单中心治理方式向多元化发展。③长三角合作共建园区的建设从突出专业化经济优势转向囊括创新、生产、居住等要素的综合性整体系统转变,是当前区域治理日趋复杂的缩影,国家到地方、政府到市场的不同行动主体都参与其中。总之,本文揭示了合作共建园区治理的新趋势,并强调同质多形框架在认识与推动当前合作共建园区新发展中的理论与实践价值。 展开更多
关键词 合作共建园区 “同质多形”理论 尺度 网络 领域 长三角
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沙颍河典型河段河岸带土壤理化性质对地下水氮污染的影响
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作者 李宝玲 杨丽虎 +1 位作者 宋献方 秦明周 《中国环境科学》 EI CAS CSCD 北大核心 2024年第7期3955-3965,共11页
以沙颍河典型河段为研究对象,通过采集果园和农田河岸带的河水、土壤以及地下水样品,并进行理化指标分析,旨在深入探讨土壤理化性质对河岸带地下水氮浓度的影响机制.结果表明:农田河岸带土壤总氮(TN)含量明显高于果园河岸带,达到其TN的1... 以沙颍河典型河段为研究对象,通过采集果园和农田河岸带的河水、土壤以及地下水样品,并进行理化指标分析,旨在深入探讨土壤理化性质对河岸带地下水氮浓度的影响机制.结果表明:农田河岸带土壤总氮(TN)含量明显高于果园河岸带,达到其TN的1.15倍,并均在距河岸约200m处达到最高值.河岸带地下水与土壤氮含量有一定的响应关系,呈现出相似的空间分布特征.农田河岸带地下水NO_(3)--N浓度(0.56~25.17mg/L)显著高于果园河岸带(0~0.97mg/L);远岸(>200m)地下水NO_(3)--N浓度均高于近岸(<100m).土壤氮素是河岸带地下水氮污染的主要来源之一.土壤中的黏土颗粒含量和施氮量较高,使得土壤颗粒更易于吸附NO_(3)--N,增加了河岸带地下水氮污染的风险.本研究揭示了河岸带土壤理化性质对地下水氮含量的影响机制,为河岸带地下水氮污染防控提供了参考依据.这些发现有助于制定可行的土地管理策略,以减缓或防止地下水氮污染的进一步扩散. 展开更多
关键词 沙颍河 河岸带 土壤理化性质 地下水氮含量 影响机制
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Analysis on the Output Elasticity and Contribution Rate of Energy Consumption to Economic Growth in China's Yangtze River Economic Zone
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作者 Maolin CHENG Yun LIU +1 位作者 Jianuo LI Bin LIU 《Journal of Systems Science and Information》 CSCD 2022年第2期150-166,共17页
Many studies have shown that energy consumption plays an important role in economic growth.The paper researches the influence of energy consumption on economic growth in China’s Yangtze River Economic Zone.The paper ... Many studies have shown that energy consumption plays an important role in economic growth.The paper researches the influence of energy consumption on economic growth in China’s Yangtze River Economic Zone.The paper divides the energy of Yangtze River Economic Zone into the coal,the oil,the natural gas and the electricity and explores the influences of coal consumption,gas consumption,natural gas consumption and electricity consumption on economic growth quantitatively using an extended production function model.The paper mainly uses two methods.The first method is the output elasticity analysis.The paper calculates the four energy consumption’s output elasticity to economic growth to compares the influences of energy consumption in terms of out output elasticity.The second method is the contribution rate analysis.The paper calculates the contribution rates of four energy consumption to economic growth to compare the influences of four energy consumption on economic growth in terms of contribution rate.The paper makes an empirical analysis on the influence of energy consumption on economic growth in China’s Yangtze River Economic Zone.Analysis results show that oil consumption has the greatest influence on economic growth in China’s Yangtze River Economic Zone,in terms of both output elasticity and contribution rate,followed by natural gas consumption,electricity consumption and coal consumption. 展开更多
关键词 yangtze river Economic zone energy consumption output elasticity contribution rate
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中国河湖岸带草本植物氮磷化学计量学及内稳性特征
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作者 杨恒 张丹 +3 位作者 李桂芳 叶远行 陈清飞 王蓉 《生态科学》 CSCD 北大核心 2024年第2期78-86,共9页
河湖岸带是拦截净化氮磷等陆源污染物进入河湖水体的最后屏障,河湖岸带草本植物的稳定性影响着其对污染物的拦截净化能力,研究河湖岸带草本植物生态化学计量学及内稳性,可为河湖岸带草本植物群落恢复和构建提供基础数据。通过对中国河... 河湖岸带是拦截净化氮磷等陆源污染物进入河湖水体的最后屏障,河湖岸带草本植物的稳定性影响着其对污染物的拦截净化能力,研究河湖岸带草本植物生态化学计量学及内稳性,可为河湖岸带草本植物群落恢复和构建提供基础数据。通过对中国河湖岸带草本植物地上部氮(N)、磷(P)含量及土壤或沉积物、水体进行数据收集,分析了植物氮磷化学计量学和内稳性特征及其与环境因子的关系。结果表明:青藏高原湖区草本植物具有较高的N含量(湿生植物:20.51 g·kg^(-1),水生植物:29.81 g·kg^(-1))和较低的P含量(湿生植物:1.39 g·kg^(-1),水生植物:0.99 g·kg^(-1)),N:P>14,表现为P限制,而其他湖区草本植物具有较高的P含量(2.73 g·kg^(-1)),N:P<14,表现为N限制。各湖区植物N、P含量及其比值在空间上具有一定差异,青藏高原湖区水生植物N含量最高,东北平原与山地湖区最低(P<0.05);东北平原与山地湖区湿生和水生植物P含量最高(P<0.05);青藏高原湖区湿生和水生植物N:P最高,东北平原与山地湖区最低(P<0.05)。植物N、P含量及N:P受环境中P含量影响最大,其次是环境中N:P和N含量。内稳性模型表明河湖岸带草本植物属于稳态型,其中湿生植物内稳性指数HN、HP及HN:P大于水生植物,表明水生植物受环境胁迫时响应较大,水生和湿生植物对环境中N、P含量变化响应的差异表明水生和湿生植物对环境中N、P不同的保守利用策略。 展开更多
关键词 生态化学计量学 内稳性 氮磷 草本植物 河湖岸带
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城镇化过程中生态产品生产能力变化特征分析——以湖北长江经济带为例
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作者 朱锦维 刘成武 +2 位作者 柯新利 黄利民 焦文轩 《生态环境学报》 CSCD 北大核心 2024年第3期469-477,共9页
城镇化过程中生态产品生产能力变化深刻,探究城镇化过程中生态产品生产能力的变化规律,对推进城镇化可持续发展和生态产品价值实现具有重要意义。目前,生态产品核算体系尚未形成统一认识,鲜有研究将乡村休闲旅游点和社区游憩公园等文化... 城镇化过程中生态产品生产能力变化深刻,探究城镇化过程中生态产品生产能力的变化规律,对推进城镇化可持续发展和生态产品价值实现具有重要意义。目前,生态产品核算体系尚未形成统一认识,鲜有研究将乡村休闲旅游点和社区游憩公园等文化服务纳入核算体系,对城镇化过程中生态产品生产能力的变化规律也缺乏系统认识。以湖北长江经济带为案例区,采用USLE、CASA等生态模型和市场价值法、替代成本法等价值评价方法,对2008、2018年研究区的生态产品生产能力进行核算,并分析其变化特征以及与城镇化的相关关系。结果表明:1)2008、2018年湖北长江经济带生态产品生产能力分别为34.21×10^(3)亿元、30.28×10^(3)亿元,其中土壤保持、气候调节和科研教育服务是生态产品生产能力的核心;2)与2008年相比,2018年湖北长江经济带生态产品生产能力下降了3.92×10^(3)亿元,降幅达11.47%,其中土壤保持能力下降显著,随着乡村旅游迅速发展,休闲游憩服务增长态势明显;3)空间变化上,湖北长江经济带三分之二的县(市、区)生态产品生产能力呈下降态势,下降区域主要分布于西部、东部地区,其中重点生态功能区下降尤为明显;4)2008、2018年湖北长江经济带城镇化与生态产品生产能力存在显著负相关关系,快速城镇化过程中,生态产品生产能力受到严峻挑战。因此,在城镇化过程中,要以“两山”理念为指导,保护生态资源基础,修复受损生态系统,开发地方特色生态产品,不断提升城乡生态产品的生产能力。 展开更多
关键词 生态产品 生产能力 生态产品价值 湖北长江经济带 城镇化
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基于随机森林模型的长江流域分区多源融合降水模拟方法研究
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作者 宋蕾玥 张珂 +3 位作者 晁丽君 李曦 牛杰帆 黄轶铭 《水资源保护》 EI CAS CSCD 北大核心 2024年第3期125-132,共8页
基于3种卫星降水产品,提出了一种基于随机森林模型的长江流域分区多源融合降水模拟算法(FCM-RF算法)。采用模糊C均值算法,结合地面观测站点资料对长江流域进行降水区域划分,引入降水比降刻画降水空间性,进一步通过普通克里金插值法优化... 基于3种卫星降水产品,提出了一种基于随机森林模型的长江流域分区多源融合降水模拟算法(FCM-RF算法)。采用模糊C均值算法,结合地面观测站点资料对长江流域进行降水区域划分,引入降水比降刻画降水空间性,进一步通过普通克里金插值法优化融合结果,得到一套长江流域空间分辨率为0.25°×0.25°的多源融合降水产品,并对其进行了评估。结果表明:FCM-RF算法在长江流域具有良好的表现,可以有效提高原始卫星降水产品对于降水事件的捕捉能力,在验证站点模拟降水量与实测降水量的相关系数可达到0.76;FCM-RF算法在年际上具有相似变化特征,对于春秋季降水的敏感性较高,在夏季由于强降水影响表现欠佳,冬季由于雨量稀少、存在固态降水,呈现出误差小、相关系数较低的特点;FCM-RF算法在东南地区具有较强的降水捕捉能力,在青藏高原地区的准确性较低。 展开更多
关键词 降水模拟 模糊C均值算法 随机森林模型 分区多源融合方法 FCM-RF算法 长江流域
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长江经济带渔业经济效率评价及差异研究
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作者 周涛 李永前 +1 位作者 程振博 余佳祥 《云南农业大学学报(社会科学版)》 CAS 2024年第2期8-15,共8页
渔业是粮食供应链中的一个重要组成部分,研究渔业经济效率,了解渔业资源开发利用的现状和问题,对于提高渔业经济效益、促进可持续发展具有重要意义。本文基于2012—2021年长江经济带11个省(市)的面板数据,结合超效率SBM模型、超效率Malm... 渔业是粮食供应链中的一个重要组成部分,研究渔业经济效率,了解渔业资源开发利用的现状和问题,对于提高渔业经济效益、促进可持续发展具有重要意义。本文基于2012—2021年长江经济带11个省(市)的面板数据,结合超效率SBM模型、超效率Malmquist指数、泰尔指数分析法解析渔业经济效率时及其差异。结果表明,长江经济带渔业经济效率总体上不断上升,逐渐呈现出下游效率最高的变化态势;渔业经济效率值趋于1,各地对于渔业投入资源的利用率较高;渔业总体发展较为均衡,渔业经济效率的差异主要由区域内的差异形成。基于此,未来长江经济带的渔业发展要注重养殖渔业技术创新、养殖规模扩大化以及区域间的协调均衡发展。 展开更多
关键词 长江经济带 渔业生产 超效率SBM MALMQUIST指数 泰尔指数
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长三角城市群低碳发展效率测度及时空格局演变
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作者 於孝平 张振龙 +1 位作者 吕连宏 孙鸿鹄 《环境科学研究》 CAS CSCD 北大核心 2024年第7期1470-1482,共13页
城市群低碳协同发展是应对气候变化、实现“双碳”目标的重要途径,测度区域低碳发展效率水平,把握其时空演变规律,对促进城市群低碳协同发展具有重要意义。本文构建低碳发展效率测算方法评估2005−2020年长三角城市群经济、社会、生态复... 城市群低碳协同发展是应对气候变化、实现“双碳”目标的重要途径,测度区域低碳发展效率水平,把握其时空演变规律,对促进城市群低碳协同发展具有重要意义。本文构建低碳发展效率测算方法评估2005−2020年长三角城市群经济、社会、生态复合维度的低碳发展效率水平,并基于此开展长三角低碳发展分区,结果表明:①构建的低碳发展效率测算方法能够有效测度城市群复合维度的低碳发展效率水平,进而得出低碳发展综合效率。②低碳发展综合效率在空间上呈现出“高值多点集聚,低值中部连片”的分布特征,低碳发展综合效率高值、较高值城市从皖中、皖北及浙南地区集聚分布演变为沪宁合杭甬发展带集聚分布,低值、较低值城市集聚于长三角中部地区,呈带状分布。③基于低碳发展效率测算结果,将长三角城市分为五类低碳发展优势区,分别为经济低碳优势区、社会低碳优势区、生态碳汇优势区、经济-社会低碳优势区和社会-生态低碳优势区。研究显示,长三角城市群各类低碳发展效率水平存在显著的空间差异,亟需针对不同分区的低碳发展特征提出差异化低碳策略,协同推进城市群绿色低碳发展。 展开更多
关键词 碳排放 低碳发展效率 低碳分区 时空格局 长三角城市群
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