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Spatio-temporal Evolution Characteristics and Driving Forces of Winter Urban Heat Island:A Case Study of Rapid Urbanization Area of Fuzhou City,China
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作者 WANG Zili LU Chunyan +4 位作者 SU Yanlin SU Yue YU Qianru LI Wenzhe YANG Nuocheng 《Chinese Geographical Science》 SCIE CSCD 2024年第1期135-148,共14页
Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly prominent.In order to promote urban sustainable development and improve the quality of human... Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly prominent.In order to promote urban sustainable development and improve the quality of human settlements,it is significant for exploring the evolution characteristics of urban thermal environment and analyzing its driving forces.Taking the Landsat series images as the basic data sources,the winter land surface temperature(LST)of the rapid urbanization area of Fuzhou City in China was quantitatively retrieved from 2001 to 2021.Combing comprehensively the standard deviation ellipse model,profile analysis and GeoDetector model,the spatio-temporal evolution characteristics and influencing factors of the winter urban thermal environment were systematically analyzed.The results showed that the winter LST presented an increasing trend in the study area during 2001–2021,and the winter LST of the central urban regions was significantly higher than the suburbs.There was a strong UHI effect from 2001 to 2021with an expansion trend from the central urban regions to the suburbs and coastal areas in space scale.The LST of green lands and wetlands are significantly lower than croplands,artificial surface and unvegetated lands.Vegetation and water bodies had a significant mitigation effect on UHI,especially in the micro-scale.The winter UHI had been jointly driven by the underlying surface and socio-economic factors in a nonlinear or two-factor interactive enhancement mode,and socio-economic factors had played a leading role.This research could provide data support and decision-making references for rationally planning urban layout and promoting sustainable urban development. 展开更多
关键词 winter urban heat island(UHI) rapid urbanization area land surface temperature(LST)retrieval profile analysis GeoDetector model Fuzhou City china
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Velocity model and time-depth conversion for the northwestern South China Sea deepwater areas
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作者 LIU Aiqun CHEN Dianyuan +2 位作者 LI Wentuo FAN Caiwei HE Jianwei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第4期56-61,共6页
There are rich natural gas resources in the northwestern South China Sea deepwater areas, with poor degree of exploration. Because of the unique tectonic, sedimentary background of the region, velocity model building ... There are rich natural gas resources in the northwestern South China Sea deepwater areas, with poor degree of exploration. Because of the unique tectonic, sedimentary background of the region, velocity model building and time-depth conversion have been an important and difficult problem for a long time. Recent researches in this direction have revealed three major problems for deepwater areas, i.e., the way to determine error correction for drilling velocity, the optimization of velocity modeling, and the understanding and analysis of velocity variations in the slope areas. The present contribution proposes technical solutions to the problems:(1) velocity correction version can be established by analyzing the geology, reservoir, water depths and velocity spectrum characteristics;(2) a unified method can be adopted to analyze the velocity variation patterns in drilled pale structural positions;and (3) across-layer velocity is analyzed to establish the velocity model individually for each of the layers. Such a solution is applicable, as shown in an example from the northwestern South China Sea deepwater areas, in which an improved prediction precision is obtained. 展开更多
关键词 time-depth conversion velocity modeling deepwater areas continental slope South china Sea
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A comparison of the management models of protected areas between China and the southern Africa region
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作者 Claudino DA VEIGA MENDONA 《Forestry Studies in China》 CAS 2010年第3期151-157,共7页
A comparison of the management models of protected areas between China and the African south region allows reading and evaluating the similarities and differences in the use of management model as a management tool fo... A comparison of the management models of protected areas between China and the African south region allows reading and evaluating the similarities and differences in the use of management model as a management tool for protected areas and specifi- cally some positive and negative features of the management approaches in these two regions. Previous to this study it verified the designation of protected areas as increasing at a faster rate than ever before, comparatively much faster now in China than southern Africa regions. With the aim of evaluating similarities and differences in the use of management model as a management tool for pro- tected areas in China and southern Africa Region, both qualitative and quantitative data were collected. Qualitative data were mainly from policy documents, scientific articles and magazine reports, whereas quantitative (secondary data) statistical data from Interna- tional Union for Conservation of Nature Resources (IUCN) and World Database on Protected Areas (WDPA). In view of the data sources above, the study found that in China all the protected areas are state owned whilst in southern Africa regions there are some protected areas that are privately owned; also that the models or typology of governance applied are successful for the fact that they both combine co-management or collaborative management, community-conserved areas and private protected areas that are subject to greater success and can help design planning and management than those who use exclusively government management. To this, the study concluded that the use of management model is influenced by the type of governance a country applies to its reserved areas. 展开更多
关键词 protected areas SUSTAINABILITY china southern Africa region management model
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A 3D basin modeling study of the factors controlling gas hydrate accumulation in the Shenhu Area of the South China Sea
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作者 Zhi-yuan Xie Jian-gong Wei +2 位作者 Jin-yun Zheng Zhen Sun Kun Zhang 《China Geology》 2022年第2期218-233,共16页
Great advancement has been made on natural gas hydrates exploration and test production in the northern South China Sea.However,there remains a lot of key questions yet to be resolved,particularly about the mechanisms... Great advancement has been made on natural gas hydrates exploration and test production in the northern South China Sea.However,there remains a lot of key questions yet to be resolved,particularly about the mechanisms and the controls of gas hydrates enrichment.Numerical simulaution would play signficant role in addressing these questions.This study focused on the gas hydrate exploration in the Shenhu Area,Northern South China Sea.Based on the newly obtained borehole and multichannel reflection seismic data,the authors conducted an integrated 3D basin modeling study on gas hydrate.The results indicate that the Shenhu Area has favorable conditions for gas hydrate accumulation,such as temperature,pressure,hydrocarbon source,and tectonic setting.Gas hydrates are most concentrated in the Late Miocene strata,particularly in the structual highs between the Baiyun Sag and the Liwan Sag,and area to the south of it.It also proved the existence of overpressure in the main sag of source rocks,which was subject to compaction disequilibrium and hydrocarbon generation.It also shown that the regional fault activity is not conducive to gas hydrate accumulation due to excess gas seepage.The authors conjecture that fault activity may slightly weaken overpressure for the positive effect of hydrocarbon expulsion and areas lacking regional fault activity have better potential. 展开更多
关键词 3D basin modeling Gas hydrates Fault reactivation OVERPRESSURE Gas seepage Heat flow NGHs exploration trial engineering Oil and gas exploration engineering Shenhu area South china Sea
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Simulation on the dynamics of forest area changes in Northeast China 被引量:11
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作者 DENG Xiangzheng JIANG Qun'ou +2 位作者 ZHAN Jinyan HE Shujin LIN Yingzhi 《Journal of Geographical Sciences》 SCIE CSCD 2010年第4期495-509,共15页
There is plenty of forests in Northeast China which contributes a lot to the conservation of water and land resources, produces timber products, and provides habitats for a huge number of wild animals and plants. With... There is plenty of forests in Northeast China which contributes a lot to the conservation of water and land resources, produces timber products, and provides habitats for a huge number of wild animals and plants. With changes of socio-economic factors as well as the geophysical conditions, there are dramatic changes on the spatial patterns of forest area. In this sense, it is of great significance to shed light on the dynamics of forest area changes to find the underlining reasons for shaping the changing patterns of forest area in Northeast China. To explore the dynamics of forest area change in Northeast China, an econometric model is developed which is composed of three equations identifying forestry production, conversion from open forest to closed forest and conversion from other land uses to closed forest so as to explore the impacts on the forest area changes from demographic, social, economic, location and geophysical factors. On this basis, we employ the Dynamics of Land System (DLS) model to simulate land-use conversions between forest area and non-forest cover and the land-use conversions within the sub-classes of forest area for the period 2000-2020 under business as usual scenario, environmental protection scenario and economic growth scenario. The simulation results show that forest area will expand continuously and there exist various kinds of changing patterns for the sub-classes of forest area, for example, closed forest will expand continuously and open forest and shrub will decrease a little bit, while area of other forest will keep intact. The research results provide meaningful decision-making information for conserving and exploiting the forest resources and makJng out the planning for forestry production Jn the Northeast China region. 展开更多
关键词 forest area forestry production econometric model dynamics of land system Northeast china
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Distribution Prediction of Suitable Growth Area for Eucommia ulmoides in China under Climatic Change Background 被引量:3
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作者 Yang Liu 《Meteorological and Environmental Research》 CAS 2013年第8期21-24,共4页
[ Objective] The research aimed to study distribution prediction of suitable growth area for Eucommia ulmoides in China under climatic change background. [ Method] By using the maximum entropy model and many kinds of ... [ Objective] The research aimed to study distribution prediction of suitable growth area for Eucommia ulmoides in China under climatic change background. [ Method] By using the maximum entropy model and many kinds of climate change scenarios, we predicted current and future distribution pattems of suitable growth area for Eucommia ulmoides in China and its change process. [ Result ] At present, highly suitable growth area of E. ulmoides mainly distributed in Sichuan, Shaanxi and Chongqing, Under climate change background, total suitable growth areas in future three decades all drastically reduced when compared with that at present. It was noteworthy that moderately and highly suitable growth areas of wild E. ulmoides all disappeared, and junction between Shaanxi and Gansu and Taibai Mountain would be stable suitable growth area of wild E. ulmoides. [ Condusioa] The research could provide useful reference data for investigation, protection and sustainable development of the wild E. ulmoides resources. 展开更多
关键词 E. ulmoides Suitable growth area Climate change The maximum entropy model Distribution prediction china
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Research on Model Construction and Technique Support for Integrated Rehabilitation of Rock Desertification in Chaoying Small Watershed of Bijie Test Area of Guizhou Province 被引量:1
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作者 Wei Qingzhang Gao Shourong +1 位作者 Jiao Li Wu Yilan 《Meteorological and Environmental Research》 CAS 2014年第8期41-47,共7页
Selecting Chaoying small watershed with representative karst rocky desertification in the Bijie test area of Guizhou Province as an example, according to karst rocky desertiflcation degree and the existing eco-environ... Selecting Chaoying small watershed with representative karst rocky desertification in the Bijie test area of Guizhou Province as an example, according to karst rocky desertiflcation degree and the existing eco-environmental problems in the small watershed, we study developmental model and technique support system for integrated rehabilitation of rocky desertification in the small watershed, and bring forward the development model and technique integration for integrated rehabilitation of rocky desertification, which adapt to the karst areas of Bijie test area, Guizhou Province and even South China. 展开更多
关键词 Rocky desertification Integrated rehabilitation Developmental model Technique integration Bijie test area china
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Evaluation of the WRF Model with Different Land Surface Schemes: A Drought Event Simulation in Southwest China during 2009–10 被引量:2
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作者 HU Zu-Heng XU Zhong-Feng +2 位作者 ZHOU Ning-Fang MA Zhu-Guo LI Guo-Ping 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第2期168-173,共6页
The authors examined the performance of version 3.4.1 of the Weather Research and Forecasting Model(WRF) with various land surface schemes in simulating a severe drought event in Southwest China. Five numerical experi... The authors examined the performance of version 3.4.1 of the Weather Research and Forecasting Model(WRF) with various land surface schemes in simulating a severe drought event in Southwest China. Five numerical experiments were completed using the Noah land surface scheme, the Pleim-Xiu land surface scheme, the Noah-MP land surface schemes, the Noah- MP scheme with dynamic vegetation, and the Noah-MP scheme with dynamic vegetation and groundwater processes. In general, all the simulations reasonably reproduced the spatial and temporal variations in precipitation, but significant bias was also found, especially for the spatial pattern of simulated precipitation. The WRF simulations with the Noah-MP series land surface schemes performed slightly better than the WRF simulation with the Noah and Pleim-Xiu land surface schemes in reproducing the severe drought events in Southwest China. The leaf area index(LAI) simulated by the different land surface schemes showed significant deviations in Southwest China. The Pleim-Xiu scheme overestimated the value of LAI by a factor of two. The Noah-MP scheme with dynamical vegetation overestimated the magnitude of the annual cycle of the LAI, although the annual mean LAI was close to observations. The simulated LAI showed a long-term lower value from autumn 2009 to spring 2010 relative to normal years. This indicates that the LAI is a potential indictor to monitor drought events. 展开更多
关键词 打表面模型 干旱 西南中国 Noah-MP 降水 叶区域索引
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Regional green innovation system mode and its implication:Acase study in eastern China coastal areas
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作者 CI Fu-yi LI Hong-fei SHI Jia-lu 《Ecological Economy》 2020年第1期35-57,共23页
Developing circular economy is the inevitable choice to realize regional sustainable development.And innovation is the fundamental driving force for regional sustainable development.Therefore,the combination of circul... Developing circular economy is the inevitable choice to realize regional sustainable development.And innovation is the fundamental driving force for regional sustainable development.Therefore,the combination of circular economy and regional innovation systems is of great value in the study of regional circular innovation systems.Based on the concepts and basic characteristics of the regional circular innovation system,the author takes Beijing,Shanghai,and Jiangsu as examples,which are the circular economy pilot provinces in developed region of eastern coastal China.With outstanding circular economy and innovation achievements,Beijing Economic-Technological Development Area,Shanghai Caohejing Hi-Tech Park,and Suzhou Industrial Park(the National Eco-Industrial Demonstration Park),served to summarize the characteristics,formation mechanism and inspiration of the circular innovation system model in capital economic-technological development zones(characterized by innovation in the recycling of water and land resources and energy,and innovation in circular service industries supplemented with"Internet+Wisdom Park"),coastal new&hi-tech industrial development zones,(featured by innovation in the recycling of water and land resources and energy,in addition,the companies’management and export processing cooperate with government)and hi-tech industrial parks(marked by open innovation and Sino-foreign governments cooperate in construction and management).This paper mainly focuses on the concepts and characteristics,formation mechanisms,evaluations,structure laws,the optimizing strategies and the cases in China to study the progress of regional green innovation system. 展开更多
关键词 regional circular innovation system model developed areas eastern coast of china
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On the Paleogene coal-measure distribution over the China sea area
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作者 LI Zeng-xue LI Ying +3 位作者 ZHOU Jing LIU Hai-yan LV Da-wei WANG Ping-li 《Journal of Coal Science & Engineering(China)》 2012年第2期147-157,共11页
关键词 中国海域 第三纪 煤系 东海西湖凹陷 含煤盆地 含煤沉积 聚煤盆地 太平洋沿岸
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Study of Finite Element Modeling of Strong Earthquake Activities and Its Preliminary Application—Taking Southwest China as an Example
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作者 ChenHuaran JiangChun +4 位作者 LiYiqun HeQiaoyun LiuJie LiLi MaHongsheng 《Earthquake Research in China》 2003年第3期236-247,共12页
Based on research result concerning the preparation and activity of strong earthquakes in groups and using the finite element method, a finite element dynamic model for Southwest China is established in this paper. Us... Based on research result concerning the preparation and activity of strong earthquakes in groups and using the finite element method, a finite element dynamic model for Southwest China is established in this paper. Using this model, the stress adjustment in the whole of the Southwest China region in response to the stress change due to strong earthquake occurrence is studied. The preliminary result shows that many strong earthquakes occurred in areas where the stress heightened after the last strong earthquake. So, the finite element model set up in this paper is useful for judging the regions where strong earthquakes are likely to occur in future. 展开更多
关键词 有限元法 模型理论 强震 地震活动性
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类型化视域下当代我国农村养老模式的比较与融合研究 被引量:1
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作者 屈振辉 张鹏 李浩平 《广东农工商职业技术学院学报》 2024年第1期5-10,共6页
农村养老是我国养老事业和养老产业的重要组成部分。当代我国农村养老模式主要有家庭养老、互助养老、机构养老和医养结合养老四种,每种模式在我国都有具有典型意义的代表。通过比较,四种模式既凸显出优势也暴露出不足。因此这四种模式... 农村养老是我国养老事业和养老产业的重要组成部分。当代我国农村养老模式主要有家庭养老、互助养老、机构养老和医养结合养老四种,每种模式在我国都有具有典型意义的代表。通过比较,四种模式既凸显出优势也暴露出不足。因此这四种模式,既要根据当地情况因地制宜选择,更要采取以一种模式为主、兼采其他模式所长的融合型模式。可以预见,融合型模式将成为我国今后农村养老发展的趋势。 展开更多
关键词 我国农村 养老模式 类型化 融合
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“双碳”目标下东北黑土区耕地利用生态效率时空格局与演变趋势
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作者 崔宁波 王婷 董晋 《水土保持研究》 CSCD 北大核心 2024年第1期335-344,共10页
[目的]探究东北黑土区耕地利用生态效率的时空格局和演变趋势,将碳源与碳汇融入耕地利用过程,这对于实现黑土减排增效和“双碳”目标至关重要。[方法]基于超效率SBM模型、核密度估计、探索性空间数据分析和空间插值工具等方法,系统考察... [目的]探究东北黑土区耕地利用生态效率的时空格局和演变趋势,将碳源与碳汇融入耕地利用过程,这对于实现黑土减排增效和“双碳”目标至关重要。[方法]基于超效率SBM模型、核密度估计、探索性空间数据分析和空间插值工具等方法,系统考察了2006—2020年东北黑土区耕地利用生态效率的时空特征与演进规律。[结果]黑土区耕地利用生态效率历经波动上升、显著下降和迅速回升3个阶段,总体处于较高发展水平,北部边缘城市的效率值明显高于中南部地区,基期和末期区间两极分化局势尤为显著,整体发展严重失衡;黑土区耕地利用生态效率全局空间相关特性并不明显,大致呈现“边缘—中心”空间扩散格局,由南北两端高值集聚向内及四周递减,而后形成多个块状高值区和低值分布带,规模集聚优势未能得到充分发挥;多数城市均存在不同程度的投入与产出冗余,劳动力和化肥冗余问题较为严重,碳排放冗余是造成黑土区耕地利用生态效率损失的普遍因素。[结论]优化要素配置和污染减排治理成为黑土利用重点改善方向,也是提升黑土区耕地利用生态效率的关键路径。 展开更多
关键词 耕地利用生态效率 “双碳”目标 超效率SBM模型 时空格局 东北黑土区
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基于非齐次灰色模型的我国东部部分地区的碳排放预测
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作者 赵国喜 方颖颖 熊作鑫 《新乡学院学报》 2024年第3期13-18,31,共7页
以2010—2019年东部部分地区的碳排放量为基础,通过量子粒子群算法对模型的未知参数进行寻优,建立了GM(1,1)模型、DGM(1,1)模型、FGM(1,1)模型和优化的灰色FQNGM(1,1,k)模型,利用这些模型对上海市、江苏省、浙江省和福建省的碳排放量进... 以2010—2019年东部部分地区的碳排放量为基础,通过量子粒子群算法对模型的未知参数进行寻优,建立了GM(1,1)模型、DGM(1,1)模型、FGM(1,1)模型和优化的灰色FQNGM(1,1,k)模型,利用这些模型对上海市、江苏省、浙江省和福建省的碳排放量进行了模拟和预测。通过对比,发现FQNGM(1,1,k)模型的模拟与预测精度最高。利用FQNGM(1,1,k)模型预测了上海市、江苏省、浙江省和福建省的碳排放量。 展开更多
关键词 灰色量子粒子群算法 东部部分地区 碳排放
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五种气候生产力模型在华北土石山区的适用性分析
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作者 江睿 郑艺伟 +3 位作者 桑玉强 孙守家 张劲松 段志强 《中国农业气象》 CSCD 2024年第4期363-373,共11页
植被净初级生产力(Net Primary Productivity,NPP)是陆地植物的净固碳量,对于全球碳估算研究具有重要意义。华北土石山区作为中国林业工程重点区域,是典型的干旱半干旱气候区,准确估算该地区NPP大小及其变化特征对林业生态工程建设具有... 植被净初级生产力(Net Primary Productivity,NPP)是陆地植物的净固碳量,对于全球碳估算研究具有重要意义。华北土石山区作为中国林业工程重点区域,是典型的干旱半干旱气候区,准确估算该地区NPP大小及其变化特征对林业生态工程建设具有重要意义。本文基于河南小浪底森林生态系统国家野外科学观测研究站1980-2020年气候数据,利用Miami模型、Thornthwaite Memorial模型、Chikugo模型、朱志辉模型及周广胜模型共5种气候生产力模型估算,分析NPP的变化趋势,运用随机森林算法探讨NPP影响因素,并以区域MODISNPP数据为标准进行评价,以探究适合估算该地区NPP的气候生产力模型。结果表明:(1)华北土石山区年平均气温、最高气温、最低气温和降水量均呈上升趋势,变化速率分别为0.05℃×a^(-1)、0.04℃×a^(-1)、0.05℃×a^(-1)和1.58mm×a^(-1);年平均太阳辐射和平均相对湿度则呈下降趋势,变化速率分别为0.46MJ×m^(-2)×a^(-1)和0.17个百分点×a^(-1)。(2)采用5种模型计算的华北土石山区NPP均呈上升趋势,但NPP值存在差异,变化范围在739.35~958.48gC×m^(-2)×a^(-1),均值为862.19gC×m^(-2)×a^(-1)。其中Miami模型估算值最大(958.48gC×m^(-2)×a^(-1)),周广胜模型估算值最小(739.35gC×m^(-2)×a^(-1))。(3)随机森林算法表明,降水是影响该地区NPP的关键因子。适用性分析显示,周广胜模型估算值与MODIS NPP最接近,其相对误差、RMSE和MAE分别为1.45%、451.05gC×m^(-2)×a^(-1)和446.03gC×m^(-2)×a^(-1),且相关系数最大(0.49)。综上可知,周广胜模型更适宜该地区的NPP估算,在使用气候生产力模型估算华北土石山区NPP时,应优先考虑使用周广胜模型。 展开更多
关键词 植被净初级生产力 气候生产力模型 华北土石山区 MODISNPP 气候因子
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基于时空多成分模型的中缅边境地区景洪市登革热流行特征分析
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作者 唐烨榕 周红宁 +1 位作者 李菁华 肖建鹏 《热带病与寄生虫学》 CAS 2024年第2期83-88,共6页
目的了解中缅边境地区景洪市2019年登革热时空分布特征及传播影响因素。方法收集中缅边境地区景洪市2019年登革热本地病例逐日发病数,将人口密度、人均GDP、日平均气温、日平均相对湿度和日照时数等因素作为协变量,构建基于Power-law算... 目的了解中缅边境地区景洪市2019年登革热时空分布特征及传播影响因素。方法收集中缅边境地区景洪市2019年登革热本地病例逐日发病数,将人口密度、人均GDP、日平均气温、日平均相对湿度和日照时数等因素作为协变量,构建基于Power-law算法的时空多成分模型,通过赤池信息量(Akaike information criterion,AIC)来评价模型的拟合效果。结果中缅边境地区景洪市2019年累计报告3303例登革热本地病例,发病率为763.44/10万。将人均GDP纳入时间自相关成分,同时将人口密度、日平均气温、日平均最高气温和日平均相对湿度纳入局部特性成分的时空多成分模型的拟合效果最优(AIC=2317),此时时间自相关成分为0.2151[95%CI:(0.0812,0.5702)]、空间流行成分为0.0004[95%CI:(0.0002,0.0010)]、局部特性成分为3.0152[95%CI:(1.6507,5.5078)]。协变量日平均相对湿度、人口密度、人均GDP、日平均气温、日平均最高气温的作用强度依次为2.8159[95%CI:(0.0216,367.1685)]、1.8227[95%CI:(1.4976,2.2183)]、1.2088[95%CI:(1.0577,1.3816)]、0.3561[95%CI:(0.0119,10.6739)]、0.3104[95%CI:(0.0036,126.5482)]。对发病数>20例的区域分析发现,允景洪街道、西双版纳旅游度假区和景洪工业园区时间自相关成分影响较大,嘎洒镇、勐龙镇和勐罕镇局部特性成分影响较大。结论景洪市不同区域登革热时空构成存在差异性,具有不同的时空传播特征。人均GDP会扩大前期疫情对后期疫情传播的影响,人口密度、日平均气温、日平均最高气温和日平均相对湿度则会影响研究区域登革热本地风险水平。 展开更多
关键词 登革热 中缅边境地区 景洪市 时空多成分模型
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中国粮食主产区耕地利用效率区域差异及影响因素——基于179个地级市的实证研究
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作者 朱梦凡 李敬锁 《水土保持通报》 CSCD 北大核心 2024年第1期206-217,共12页
[目的]粮食主产区在实现粮食稳产保供中具有重要的战略地位。研究粮食主产区的耕地利用效率及其时空演变特征,旨在为促进粮食主产区耕地资源高效利用、保障粮食安全及实现农业可持续发展提供参考。[方法]创新性地运用两阶段动态网络DEA... [目的]粮食主产区在实现粮食稳产保供中具有重要的战略地位。研究粮食主产区的耕地利用效率及其时空演变特征,旨在为促进粮食主产区耕地资源高效利用、保障粮食安全及实现农业可持续发展提供参考。[方法]创新性地运用两阶段动态网络DEA模型,测算粮食主产区2010—2020年179个地级市耕地利用效率,并通过ArcGIS可视化技术和核密度估计分析其时空演变特征,构建Tobit模型并探究耕地利用效率影响因素。[结果]2010—2020年粮食主产区整体效率水平呈“小幅下降—快速上升—波动增长”的阶段趋势,整体效率水平偏低,仍具有较大提升空间。分阶段来看,生产阶段效率水平始终高于消费阶段,且两阶段效率水平差距有进一步增大的态势;粮食主产区耕地利用效率提升受两阶段效率水平共同作用的影响,生产阶段是效率提升的主要动力,阻力来自于消费阶段效率。分区域来看,松花江流域>长江流域>黄河流域的耕地利用效率,区域不均衡性显著。从空间上来看,整体效率、生产阶段效率高值区呈东北—西南空间分布,并逐渐形成“高—高”集聚和“低—低”集聚的空间格局,消费阶段效率高值区呈离散化分布格局,并未呈现出向提升方向收敛的发展态势。整体、生产阶段和消费阶段的外部影响因素不尽相同,涉及社会经济发展水平、城乡发展水平、科技水平及农业基础设施建设。同时不同因素对不同区域的整体及各子阶段耕地利用效率作用强度及作用方向也存在显著差异。[结论]未来粮食主产区不但要探索区域差异化耕地利用路径,加强各地级市间合作,更要在提升生产阶段效率的同时,重点关注各地级市消费阶段效率提升收敛速度以及与生产阶段效率差距之间的协调。 展开更多
关键词 耕地利用效率 时空特征 影响因素 DEA模型 粮食主产区 中国
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南海北部陆缘盆地深水区油气勘探新认识及攻关方向 被引量:2
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作者 谢玉洪 《天然气工业》 EI CAS CSCD 北大核心 2024年第1期13-25,I0001,共14页
南海北部陆缘盆地深水区已成为我国海洋油气勘探增储上产的重要领域,但由于构造演化史复杂,该区不同凹陷的沉积—构造特征、烃源岩生烃—储层成岩演化和成藏模式均存在明显差异。为准确认识该区油气勘探潜力和方向,基于前人研究成果和... 南海北部陆缘盆地深水区已成为我国海洋油气勘探增储上产的重要领域,但由于构造演化史复杂,该区不同凹陷的沉积—构造特征、烃源岩生烃—储层成岩演化和成藏模式均存在明显差异。为准确认识该区油气勘探潜力和方向,基于前人研究成果和勘探实践,在综合分析烃源岩、储层、差异成藏等地质条件的基础上,剖析了南海北部陆缘盆地深水区成藏特征、油气勘探作业面临的挑战,并指出了下一步油气攻关研究方向。研究结果表明:①受地壳拆离作用及强烈薄化影响,该区地层沉积特征特殊,岩石地球物理性质多样;②软流圈差异抬升形成深水区独特的高热流背景,促使区域性湖相、煤型及叠合型等3类烃源灶快速、高强度生烃,生烃门限变浅;③深水盆地群的演化和成盆规模差异大,构造演化控制了盆地几何形态和储集体时空展布,深水区独特的板块构造位置、复杂的构造演化史、温压变化剧烈的地质特征等控制了油气成藏模式。结论认为:①该区油气勘探面临地震资料解析度低、规模有效储层预测困难、勘探成本高等技术与经济的双重挑战;②需要创新形成高地温背景下优质储层差异化分布规律的研究思路;③亟需提升勘探设备能力建设,攻关高效地震采集、“重磁电震”地球物理一体化采集处理、双井架钻探作业、多井段“一趟钻”等勘探关键技术,为我国海洋深水油气勘探开发的高质量发展做好理论和技术支撑。 展开更多
关键词 南海北部 陆缘盆地深水区 烃源岩类型 烃源灶 成藏模式 构造演化 勘探挑战 高效勘探作业
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西南山区乡村人居环境治理:模式比较与政策启示——以4个典型村落为例
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作者 张会吉 陈静 《江汉大学学报(社会科学版)》 2024年第1期32-44,共13页
探索乡村人居环境治理的有效模式对推进乡村建设,促进乡村振兴具有重要意义。文章基于西南山区4个典型村落人居环境治理的实地调研,依据农户行为理论、公共选择理论、委托代理理论和多中心治理理论,按照治理主体力量的不同,将其划分为... 探索乡村人居环境治理的有效模式对推进乡村建设,促进乡村振兴具有重要意义。文章基于西南山区4个典型村落人居环境治理的实地调研,依据农户行为理论、公共选择理论、委托代理理论和多中心治理理论,按照治理主体力量的不同,将其划分为村民自主治理、政府治理、市场治理和多中心治理4种主要模式,并深入比较4种治理模式的实践机制。研究发现:4种模式在乡村人居环境治理中各有利弊,且适用环境不尽相同。距县城、中心镇较远,宗亲关系密切和农户较为分散的村落适宜推行村民自主治理模式;人口较为集聚且政府治理能力强的村落适宜推行政府治理模式;资源禀赋强、人文历史和交通条件好的村落适宜推行市场治理模式;村落发展较好且利益联动机制较为完善的村落,适宜推行多中心治理模式。西南山区乡村人居环境治理水平总体较低,后续治理任务依然艰巨,针对政府治理成本大、市场进出机制不完善和村民参与不积极等问题,从政府、市场和村民等视角提出了相应建议。 展开更多
关键词 西南山区 乡村人居环境 治理模式 政策启示 典型村落
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中国-东盟自贸区背景下食品类人才培养探究——以南宁学院食品质量与安全专业为例
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作者 程忠 张婷 朱芙蓉 《高教学刊》 2024年第4期17-20,共4页
广西是中国-东盟自由贸易区的开放前沿,其与东盟国家贸易的快速发展对区域内的食品类人才培养提出新要求。该文通过分析现阶段广西食品类人才在区域性国际化方向培养中存在的问题,立足南宁学院食品质量安全专业的办学特色,提出从实践教... 广西是中国-东盟自由贸易区的开放前沿,其与东盟国家贸易的快速发展对区域内的食品类人才培养提出新要求。该文通过分析现阶段广西食品类人才在区域性国际化方向培养中存在的问题,立足南宁学院食品质量安全专业的办学特色,提出从实践教学体系、课程体系、教育评价体系及实践教学能力出发,探讨服务中国-东盟自贸区发展的人才培养模式,以期为区域性、复合型人才的培养模式提供新思路。 展开更多
关键词 食品质量与安全 中国-东盟自由贸易区 国际化人才 复合型人才 培养模式
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