检索结果-南通市图书馆

Separating the impacts of climate variability,land-use change and large reservoir operations on streamflow in the Yangtze River basin,china,using a hydrological modeling approach

引用

International Journal of Digital Earth 2021年第2期14卷 231-249页

作者： Ning Nie Wanchang Zhang Min liu Hao Chen Dengzhong zhao Key Laboratory of geographic Information Science of the Ministry of Education School of Geographic SciencesEast China Normal UniversityShanghaiPeople’s Republic of China Aerospace Information research institute Chinese Academy of SciencesBeijingPeople’s Republic of China institute of Eco-Chongming(IEC) ShanghaiPeople’s Republic of China institute of Surface-Earth System Science School of Earth System ScienceTianjin UniversityTianjinPeople’s Republic of China Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim Tianjin UniversityTianjinPeople’s Republic of China Changjiang River Scientific research institute WuhanPeople’s Republic of China

Separating the individual effects of climate variability and human activities on streamflow is more important than just knowing their combined *** this paper,using a scenario-based hydrological simulation approach,the streamflow changes caused by climate variability and two different types of human activities(***-use change and large reservoirs operations)as well as the contribution rates of these three factors over 2.2.sub-basins in the Yangtze river basin were quantified and compared among 5 different periods(i.e.1988–1992.P1),1993.1.97(P2.,1998–2.02.P3),2.03–2.07(P4)and 2.08–2.12.P5)).Results demonstrate that,at the annual scale,climate variability played a leading role in the change in outflow of most *** regard to the seasonal variations in discharge at Datong station,climate factors played a predominant role during P1-P2.and *** the Three Gorges Reservoir began operating in 2.03,the discharge was enhanced by reservoirs in January-May and reduced by reservoirs in July*** and climate factors codetermined seasonal streamflow change during P3-P4 and ***-use change made the smallest contribution to seasonal discharge *** study can support decision-making in regional water resources planning and management.

关键词： Climate variability land-use change reservoirs streamflow Yangtze River Basin

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Bias Analysis in the Simulation of the Western North Pacific Tropical Cyclone Characteristics by Two High-Resolution Global Atmospheric Models

引用

Advances in Atmospheric sciences 2023年第4期40卷 634-652页

作者： Qiyang liu Fengxue QIAO Yongqiang YU Yiting ZHU Shuwen zhao Yujia liu Fulin JIANG Xinyu HU Key Laboratory of geographic Information Science Ministry of EducationEast China Normal UniversityShanghai 200241China School of geographic sciences East China Normal UniversityShanghai 200241China Climate Environment and Sustainability CenterSchool of Atmospheric ScienceNanjing University of Information Science and TechnologyNanjing 210044China State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of the chinese academy of sciences Beijing 100049China Department of Atmospheric and Ocean sciences Institute of Atmospheric SciencesFudan UniversityShanghai 200438China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081China

This study compares the atmosphere-only HighResMIP simulations from FGOALS-f3-H(FGOALS)and MRIAGCM3-2.S(MRI)with respect to tropical cyclone(TC)characteristics over the Western North Pacific(WNP)for the July-October months of *** focus is on investigating the role of the tropical easterly jet over the Western Pacific(WP_TEJ)in modulating the simulation biases in terms of their climatological distribution and interannual variability of WNP TC genesis frequency(TCGF)based on the analysis of the genesis potential index(GPI).Results show that the two models reasonably capture the main TC genesis location,the maximum center of frequency,and track density;however,their biases mainly lie in simulating the intense TCs and TCGF *** MRI better simulates the windpressure relationship(WPR)but overestimates the proportion of super typhoons(SSTYs).At the same time,FGOALS underestimates the WPR and the proportion of SSTYs but better simulates the total WNP TC *** particular,FGOALS overestimates the TCGF in the northeastern WNP,which is strongly tied to an overestimated WP_TEJ and the enhanced vertical circulation to the north of its entrance *** contrast,the MRI simulates a weaker WP_TEJ and vertical circulation,leading to a negative TCGF bias in most of the *** models exhibit comparable capability in simulating the interannual variability of WP_TEJ intensity,but the composite difference of large-scale atmospheric factors between strong and weak WP_TEJ years is overestimated,resulting in larger interannual anomalies of WNP TCGF,especially for ***,accurate simulations of the WP_TEJ and the associated oceanic and atmospheric factors are crucial to further improving WNP TC simulations for both models.

关键词： tropical cyclone genesis HighResMIP tropical easterly jet

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

磷指数模型在美国的应用和发展

引用

农业环境科学学报 2024年第5期43卷 965-973页

作者：马华雷秋良杜新忠赵营李影安妙颖武淑霞樊秉乾刘宏斌农业农村部面源污染控制重点实验室/北京昌平土壤质量国家野外科学观测研究站/北方干旱半干旱耕地高效利用全国重点实验室中国农业科学院农业资源与农业区划研究所北京100081 宁夏农林科学院农业资源与环境研究所银川750002 中国科学院地理科学与资源研究所资源与环境信息系统国家重点实验室北京100101

磷是植物生长必需的营养元素之一,在农业生产中起着关键作用。然而,长期过量的磷肥投入导致土壤磷素水平增加,进而加大了土壤磷素流失风险,造成农业非点源磷污染,同时这也成为导致水体富营养化的主要因素之一。因此,识别和管理农业非点... 详细信息

磷是植物生长必需的营养元素之一,在农业生产中起着关键作用。然而,长期过量的磷肥投入导致土壤磷素水平增加,进而加大了土壤磷素流失风险,造成农业非点源磷污染,同时这也成为导致水体富营养化的主要因素之一。因此,识别和管理农业非点源磷的流失风险关键区,成为面源污染亟待解决的关键问题。磷指数模型起源于2.世纪90年代,是评估农田磷流失潜力和指导磷管理决策的重要工具之一。根据研究区特点,美国众多学者在各州设立了不同的磷指数指标体系,优化了磷指数的组成因子、计算方法和分级标准。本文对美国各州磷指数模型评价体系进行了综述和评价,指出了磷指数模型的局限性,提出了改进方向,以期为我国磷素管理方法提供借鉴。

关键词：磷指数非点源污染磷素迁移评价体系流失风险

来源：

维普期刊数据库博看期刊

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The evolution of tea spatial agglomeration in china:An analysis based on different geographical scales

引用

Journal of Mountain Science 2018年第12期15卷 2590-2602页

作者： liu Han-chu FAN Jie ZENG Yu-xi WANG Wen-zhao Key Laboratory of Regional Sustainable DevelopmentModeling ChineseAcademy of SciencesBeijing 100101China institute of C-eography Science andnatural {2. research ChineseAcademy of SciencesBeIjing 100101China University of chinese academy of sciences Beijing 10049China National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene research (Wuhan) Huazhong Agricultural UniversityWuhan 430070China

The spatial agglomeration of agricultural production is conducive to reducing planting costs, increasing production efficiency and improving product quality. It is an important way to promote the transformation and upgrad of tea industry and realize the modernization of china's tea industry. This study used Gini coefficient and spatial autocorrelation analysis to explore the characteristics of tea spatial agglomeration in china from three {2.al scales: regional level, provincial level and prefecture level from the year 2.05 to 2.15. The results indicated that there was a significant scale effect on the tea spatial agglomeration. The agglomeration degree increased from the regional level, provincial level to prefecture level. The types of spatial agglomeration evolution of the three scales were Ushaped, continuous diffusion, and continuous agglomeration. The spatial autocorrelation of tea production could only be found at the prefecture level. Meanwhile, at the prefecture scale, we could not only reveal the pattern changes at the regional and provincial levels, but also identify tea production agglomeration regions. Compared with the large scale, the small scale could reveal the characteristics of tea spatial agglomeration in more details. Factors such as natural resource endowments, cost factor, technological advancement, agglomeration economy, and agricultural policy influenced the evolution of tea spatial agglomeration from different {2.al scales. Finally, from the perspectives of spatial transfer of tea production, promoting spatial agglomeration, building tea production bases, and breaking administrative boundaries, we proposed several policy suggestions for optimizing the spatial layout of tea production.

关键词： Tea production Spatial agglomeration geographic scale Driving Factors china

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Parameter regionalization of the FLEX-Global hydrological model

引用

Science china Earth sciences 2021年第4期64卷 571-588页

作者： Jingjing WANG Hongkai GAO Min liu Yongjian DING Yan WANG Fang zhao Jun XIA Key Laboratory of geographic Information Science(Ministry of Education of china) Shanghai 200241China School of geographical sciences East China Normal UniversityShanghai 200241China State Key Laboratory^of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Journal Editorial Department of Anhui Agricultural University Hefei 230036China State Key Laboratory of Water resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China

Global hydrological models(GHMs) are important tools for addressing worldwide change-related water resource problems from a global perspective. However, the development of these models has long been hindered by their low accuracy. In order to improve the streamflow simulation accuracy of GHMs, we developed a GHM—the FLEX-Global—based on the regionalization of hydrological model parameters. The FLEX-Global model is primarily based on the framework of the FLEX hydrological model coupled with the HAND-based Storage Capacity curve(HSC) runoff generation module to calculate net rainfall, and uses the global river-routing Ca Ma-Flood model to calculate river network routing. This new model allows for streamflow simulation at a spatial resolution of 0.5°×0.5° and a temporal resolution of 1 day in global catchments. To validate FLEX-Global accuracy, the FLEX-Global-simulated streamflow of 2. major rivers distributed in five different climate zones was compared with the observed data from the Global Runoff Data Center(GRDC). Next, the model performance of FLEXGlobal was further verified by comparing it with that of seven existing GHMs with varying accuracy in the five climate ***-metric evaluation indicated that the streamflow simulation accuracy was improved by the FLEX-Global model with regionalized parameters, especially in the tropical and dry climate zones. This newly-developed GHM with regionalized parameters can provide scientific support for the assessment of climate change impact, optimization of global water resource mangement, simulation of Earth's multi-sphere coupling, and implementation of the Inter-Sectoral Impact Model Intercomparison Project(ISIMIP).

关键词： Global hydrological model Model performance Parameter regionalization

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

SAR image water extraction using the attention U-net and multi-scale level set method:flood monitoring in South china in 2.2. as a test case

引用

Geo-Spatial Information Science 2022年第2期25卷 155-168页

作者： Chuan Xu Shanshan Zhang Bofei zhao Chang liu Haigang Sui Wei Yang Liye Mei School of Computer Science Hubei University of TechnologyWuhanChina geographic Information Center GuangZhou Urban Planning&Design Survey Research InstituteGuangzhouChina State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanChina School of Information Science and Engineering Wuchang Shouyi UniversityWuhanChina The institute of Technological sciences Wuhan UniversityWuhanChina

Level set method has been extensively used for image segmentation,which is a key technology of water ***,one of the problems of the level-set method is how to find the appropriate initial surface parameters,which will affect the accuracy and speed of level set ***,the semantic segmentation based on deep learning has opened the exciting research *** addition,the Convolutional Neural Network(CNN)has shown a strong feature representation ***,in this paper,the CNN method is used to obtain the initial SAR image segmentation map to provide deep a priori information for the zero-level set curve,which only needs to describe the general outline of the water body,rather than the accurate *** with the traditional circular and rectangular zero-level set initialization method,this method can converge to the edge of the water body faster and more precisely;it will not fall into the local minimum value and be able to obtain accurate segmentation *** effectiveness of the proposed method is demonstrated by the experimental results of flood disaster monitoring in South china in 2.2..

关键词： Water extraction flood monitoring level set attention U-net Convolutional Neural Network(CNN)

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

The Development of Khorgas Port in Xinjiang, china and Its Effect on Surrounding Towns

引用

chinese geographical Science 2023年第3期33卷 458-473页

作者： DONG Junxi liu Hanchu zhao Yannan CHEN Dong QIAO Qin FAN Jie School of Economics and Management University of Chinese Academy of SciencesBeijing 100190China institute of Science and Development Chinese Academy of SciencesBeijing 100190China institute of geographic {2. and natural resources research Chinese Academy of SciencesBeijing 100101China chinese research {2. of Environmental sciences Institute of EcologyBeijing 100049China

The sustainable development of border port-cities is of considerable significance to the stabilization and consolidation of border areas,unlike coastal-ports cities that consist of coastal ports and *** ports should continue to drive the development of their surrounding towns to provide high-quality living conditions,employment,and housing for inhabitants of such towns and enhance the population agglomeration capacity of border *** study aimed to analyze the structure of employment and settlement in the cities surrounding the Khorgas Port at the different stages of its development—employing semi-structured interviews with individuals to analyze the spatial orientation characteristics of the daily needs of different groups of people and reveal the ways in which border ports drive the development of their surrounding towns—and recommend ways in which this can be *** study finds that as the Khorgas Port’s mutual trade market,industrial base,comprehensive management,and other functions continue to grow,the port is becoming increasingly *** more people work and settl in the surrounding towns,their living needs also ***,a considerable number of employed people do not live nearby,and many living needs are not being addressed in the towns surrounding the *** study also reveals the living services demands of government management personnel who work at the port on weekdays and return to Yining City on weekends,employees of industrial enterprises who work at the port and return home for the New Year’s celebration,and government management personnel and individual business personnel who work at the port and live *** the future,the focus should be on improving the living conditions of the inhabitants of the towns surrounding Khorgas Port,including public services and the settlement ability of employees of industrial enterprises to better realize the radiation drive of the port on the surrounding towns.

关键词： return services coastal

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Dynamic Assessment and Sustainability Strategies of Ecological Security in the Irtysh River Basin of Xinjiang, china

引用

chinese geographical Science 2023年第3期33卷 393-409页

作者： FAN Jie ABUDUMANAN Ahemaitihali WANG Li ZHOU Daojing WANG zhao liu Hanchu institute of geographic {2. and natural resources research Chinese Academy of SciencesBeijing 100190China institutes of Science and Development Chinese Academy of SciencesBeijing 100190China School of Economics and Management University of Chinese Academy of SciencesBeijing 100190China University of chinese academy of sciences Beijing 100049China

The drylands of china are extensive,and they are home to more than one-third of the country’s ***,the watershed territories of the drylands,where the majority of human activities are concentrated have long experienced strained human-land relationships,culminating in ecological security ***,it is essential to carry out a comprehensive assessment of the ecological security of dryland watersheds and to identify the key factors influencing ecological security in order to formulate strategies that ensure the sustainability of *** on the Driving-Pressure-State-Impact-Response(DPSIR)model,this study developed an ecological security index and applied it to the Irtysh River Basin of Xinjiang,china,from 2.00 to *** obstacle degree model was applied to reveal the obstacles in two dimensions:criterion level and indicator *** findings suggested that the ecological security comprehensive index in the Irtysh River Basin has increased significantly from 2.00 to 2.2.,irrespective of the fact that it decreased during the study period and then *** ecological security level changed from‘critically safe’in 2.00 to‘general safety’in 2.2.,with the state subsystem and pressure subsystem becoming ecological security *** primary factors influencing the ecological security of the study area were water consumption,the area of high-efficiency water-saving irrigation,the proportion of wetland area,vegetation coverage,and livestock *** ecological security of different counties in the basin varies greatly,whereas the factors that influence ecological security showed both similarities and differences among the *** light of on the findings,we proposed that future strategies for ecological security enhancement should concentrate on enacting the policy of localizing spatial differentiation,optimizing industrial structure,strengthening scientific and technological support in the field of water conservat

关键词： subsystem watershed dimensions

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

geographic Variation in Clutch and Egg Size for the Lizard Phrynocephalus przewalskii(Squamata:Agamidae)

引用

Asian Herpetological research 2011年第2期2卷 97-102页

作者： Yajuan WANG Weihong JI Wei zhao Nannan YU Naifa liu School of Life sciences Lanzhou University institute of natural {2. Massey UniversityPrivate Bag 102904North Shore Mail Centre

In order to tease apart proximate vs. ultimate sources of variation in reproductive strategy, studies have increasingly focused on populations rather than species as the unit of interest. The reproductive parameters of Phrynocephalus przewalskii （Agamidae） in different populations within the same phylogenetic clade were compared in this study. Female SVL, clutch size, egg volume and clutch volume varied significantly among populations. With increase in latitude, clutch size increased, while egg size decreased. Relatively fewer but larger eggs were produced with increasing of population density. Food availability had positive effects on clutch size, but no effect on egg size. Our result indicated that latitude, food availability and population density may be the proximate factors affecting the reproductive parameters ofP. przewalskii.

关键词： Phrynocephalus przewalskii reproductive parameter geographic variation egg size clutch size

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Assessing Crop Water Demand and Deficit for the Growth of Spring Highland Barley in Tibet, china

引用

Journal of Integrative Agriculture 2013年第3期12卷 541-551页

作者： liu zhao-fei YAO Zhi-jun YU Cheng-qun ZHONG Zhi-ming institute of geographic {2. and natural resources research Chinese Academy of Sciences

The aim of this study was to assess the crop water demand and deficit of spring highland barley and discuss suitable irrigation systems for different regions in Tibet, china. Long-term trends in reference crop evapotranspiration and crop water demand were analyzed in different regions, together with crop water demand and deficit of spring highland barley under different precipitation frequencies. Results showed that precipitation trends during growth stages did not benefit the growth of spring highland barley. The crop coefficient of spring highland barley in Tibet was 0.87 and crop water demand was 389.0 ram. In general, a water deficit was found in Tibet, because precipitation was lower than water consumption of spring highland barley. The most severe water deficit were in the jointing to heading stage and the heading to wax ripeness stage, which are the most important growth stages for spring highland barley; water deficit in these two stages would be harmful to the yield. Water deficit showed different characteristics in different regions. In conclusion, irrigation systems may be more successful if based on an analysis of water deficit within different growth stages and in different regions.

关键词： Tibet highland barley Penman-Monteith reference crop evapotranspiration crop water requirement crop coefficient crop water deficit

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：