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1.
The research progress of climate suitability at home and abroad was briefly reviewed in this paper, which was divided into three stages: The initial stage of research, the initial development and application stage, and the application research warming stage. The main achievements and progress of climate suitability in China were also introduced from three aspects as follows: Improvement of climate suitability model, extension of climate suitability applications and development of climate suitability model. Based on the impact of climate change on agriculture and the weak links in climate suitability research, the focus and hotspot of future climate suitability research were proposed, which will be five important directions:The climate suitability model proceed from crop growth model, the climate suitability research proceed from characteristic agriculture, the climate suitability research proceed from climate change, the climate suitability model based on different theories and the climate suitability evaluation index research.  相似文献   

2.
国内外城市化水文效应研究综述   总被引:3,自引:0,他引:3  
城市化等人类活动导致的土地利用方式的改变是城市生态学研究的重要内容之一,而由于城市化进程造成的城市水文效应是其重要的研究方向。本文通过介绍城市化的内涵以及城市化水文效应国内外的最新研究进展,归纳了城市化导致的城市水文效应的主要研究方向和内容,具体包括城市化对径流、蒸散发等各种水文要素及其水质的影响,并针对目前城市化水文效应的研究方法—流域对比实验法、水文特征参数法和流域水文模型法进行了总结,最后指出了当前城市化水文效应研究中存在的问题和不足,对未来的研究趋势进行了展望。  相似文献   

3.
气候适宜度国内外研究进展及展望   总被引:1,自引:0,他引:1  
简要概述了国外在气候适宜度方面的研究现状,回顾了我国在气候适宜度方面的研究历程,将气候适宜度研究划分为3个阶段:研究的起步阶段、初步发展应用阶段及应用研究升温阶段。从气候适宜度模型的改进、气候适宜度应用的延伸及气候适宜度模型的发展3个方面介绍了我国在气候适宜度方面的主要成果和进展;从气候变化对农业的影响角度及气候适宜度研究存在的薄弱环节等方面,提出立足作物生长模型的气候适宜度模型研究、立足特色农业的气候适宜度研究、立足气候变化的气候适宜度研究、立足不同理论的气候适宜度模型研究和气候适宜度评价指标研究等方面将是未来气候适宜度研究的重点和热点。  相似文献   

4.
国内外泥浆材料的现状及发展趋势   总被引:7,自引:0,他引:7       下载免费PDF全文
系统介绍了泥浆材料的现状及发展趋势,重点叙述了水基泥浆、油基泥浆及合成基泥浆这3大类泥浆材料的现状及发展趋势。  相似文献   

5.
近年来,随着我国城市化快速发展,城市地面空间资源难以负荷,国家大力支持开发利用城市地下空间。本文概述我国城市地下空间开发和利用的发展历程和城市地下空间开发利用保护工作的相关政策,梳理我国现行城市地下空间标准以及国际国外现行城市地下空间标准,并分析存在的问题。针对存在的问题,参考当前国际上现有标准,提出城市地下空间标准发展建议,逐步建立和完善我国城市地下空间标准体系,促进我国城市地下空间可持续发展。  相似文献   

6.
高温盐水钻井液技术难点及国内外研究现状   总被引:3,自引:0,他引:3  
单文军 《地质与勘探》2013,49(5):976-980
在分析高温盐水钻井液面临的主要问题的基础上,对国内外抗高温、抗污染钻井液处理剂及钻井液体系的研究与应用情况进行了介绍。深井、超深井钻探中会面临各种复杂情况,因此对钻井液抗温、抗污染能力的要求也越来越高,主要技术难点是高温高压及高污染条件下对钻井液流变性、滤失量、腐蚀性的控制。耐260℃以上抗高温、抗盐处理剂及体系,耐高温钻井液测试仪器是未来抗高温钻井液发展的方向。  相似文献   

7.
山东省沂沭河干流水环境质量评价与趋势分析   总被引:1,自引:0,他引:1  
张涛  刘洪林  张勇  吴启鲁 《地下水》2003,25(3):183-185
根据多年水质监测资料,对沂沭河干流水环境质量进行综合评价;采用Kendall季节检验趋势分析法,对沂沭河水系水环境质量变化趋势进行了探讨,为治理改善沂沭河水环境质量提供科学依据。  相似文献   

8.
In June 2014, the Ministry of Civil Affairs, the National Disaster Reduction Committee Office issued the “Statistical System of Large-scale Natural Disasters Damage and Loss” (SSLNDD&L), in which the standard statistical content and index were explored. Examined by several major natural disasters in recent years, such as Ludian earthquake (Ms 6.5) on 3 August 2014, Nepal earthquake (Ms 8.1) on 25 April 2015, SSLNDD&L provided good basis for post disaster recovery and reconstruction planning, but the direct guidance of reconstruction planning was still limited. Post Disaster Needs Assessment (PDNA), the mainstream of the international disaster needs assessment system, was taken as the main research object, and the content and characteristics of PDNA system were analyzed in detail. The comparison analysis was made from the objectives, contents and index system, evaluation methodology, evaluation parameters between the SSLNDD&L and PDNA. In the future, expanding and increasing various industries and local evaluation index focusing on recovery and reconstruction needs, optimizing the disaster assessment parameter database used for the multi-user such as the Central-Province-County scale, supporting the preparation of technical standard optimization evaluation process to form a complete assessment technical specification should be put forward as the future development of the SSLNDD&L. It is of great practical significance to optimize and perfect the content and index of the SSLNDD&L to better serve the decision making of the recovery and reconstruction after large-scale disasters, and to achieve international standards on large-scale disaster damage & loss statistics and assessment in China.  相似文献   

9.
放射性废物处置研究进展   总被引:1,自引:0,他引:1  
放射性废物的处置是制约核能可持续发展的关键因素,目前已成为国际社会关注的热点问题之一.针对处置场地核素运移污染的风险问题,对放射性废物的处置及其选址、核素运移试验和核素运移模型进行了回顾和论述.指出采用多重屏障系统进行放射性废物的处置,其安全性是可以得到保障的;处置场的选址应遵循就近原则,并应从环境水文地质的角度来构建...  相似文献   

10.
结合多指标因子评价方法的研究成果及北京地区突发地质灾害与避险场所的特征,提出了一种新的避险场所适宜性评价方法,即"决定性与程度性指标分析法",应用于北京市避险场所的选址评价得到了良好的效果。  相似文献   

11.
Global climate change featured with warming has created serious challenge to world sustainable development and human security. It has become an important consensus of the international society to assess global change risk at the global scale and carry out tailored governance and risk-based adaptation. National Key Research and Development Program “Study on global change population and economic system risk forming mechanism and assessment” aims at quantitatively predicting future global climate change and population and economic system exposure and vulnerability change, developing global change population and economic system risk assessment model based on complex system dynamics, synthesizing risk assessment model with proprietary intellectual property rights, assess global change population and economic system risk of the near and mid future at the global scale, and compiling the atlas of global change population and economic system risk. The outcomes intend to serve the participation of global risk governance and international climate negotiation, and to provide scientific support to the implementation of international disaster risk reduction strategy.  相似文献   

12.
阜新煤田东梁区沙海组煤成气成藏条件分析   总被引:5,自引:0,他引:5  
阜新煤田东梁区沙海组赋存有可观的煤成气资源(煤层气和砂体气)。通过对气源岩的生气能力、储集岩的储气能力、盖层的圈闭条件研究,认为沙海组煤成气具有良好的成藏条件。  相似文献   

13.
As an important exchange process of water and heat between the cryosphere and the atmosphere, snow and glacier sublimation is a principal pathway of moisture content loss of cryosphere. The observations and simulations of snow and glacier sublimation for the process and influencing factors were conducted earlier in the Antarctic and the Arctic Pole, North America and northern Europe, and had made great progress. Based on the analysis of the sublimation of ice and snow and the latent heat of sublimation in different regions and climatic conditions, the influencing factors to sublimation of ice and snow were analyzed. Although sublimation of ice and snow is an important part of regional hydrological process and energy budget balance, under humid climate conditions, sublimation of ice and snow is inhibited. it is greatly affected by local topography(elevation, slope and aspect), vegetation and meteorological elements, resulting in large differences in reported sublimation of ice and snow. However, there are many factors that affect the sublimation, resulting in the obvious spatial and temporal differences of research results. The researches lack of long-term, systematic observation and research, and which has contributed to the lack of understanding in the water-heat process of snow and glacier. There are still great uncertainties and difficulties in this study that need to be overcome.  相似文献   

14.
周启鸣  李剑锋  崔爱红  刘会增 《水文》2021,41(1):15-21,72
集中回顾中亚干旱区陆地水资源评估手段进展.水资源评估手段主要可分为基于观测数据和水文模型模拟两大类.从数据获取手段来讲,站点实测、遥感、再分析数据是目前中亚水资源评估的主要数据来源.其中,遥感数据又可分为成像遥感数据以及非成像遥感数据(包括雷达高度计、重力卫星数据).由于干旱区站点资料缺乏,遥感与水文模型集成已经成为常...  相似文献   

15.
地下水超采引发的诸多环境地质问题制约着当地的社会经济发展,亟需加强对地下水资源的管理和保护。为合理规划管理地下水超采区,本文探讨了超采区的概念,归纳总结出超采区的自然属性和社会属性,认为超采区为"在一定时期内,地下水开采量超过一阈值而对地下水系统或局部的地质环境或水生态环境等产生一定损害或裂变影响的区域";阐述了超采区的评价指标与单因子评价、多因子系统分析以及数值模拟法等评价方法,同时对不同方法进行了比较分析;在此基础上,提出区域数值模拟-局部水位动态联合评价法,并以潍坊北部地区为例,验证了区域数值模拟-局部水位动态联合评价法的实用性。  相似文献   

16.
This paper analyzes the variation of meridional temperature gradient (MTG) over mid-latitude and high-latitude of Northern Hemisphere continents during last 100 years using observational data. It is found that MTG over high-latitude of Northern Hemisphere continents has an increasing trend, but the simulation results of CMIP5 models show a decreasing trend. Results of this study showed the decrease of MTG over the high-latitude continents of Northern Hemisphere calculated by CMIP5 historical simulations mainly because the models of CMIP5 exaggerated ice-albedo feedback over high-latitude regions. A series of simulation results by energy balance climate models showed that ice-albedo feedback amplified the magnitude of warming in the global warming induced only by carbon dioxide, and the magnitude of warming in high latitude was much larger than that in low-latitude regions. Along with global warming, ice-albedo feedback has little influence on MTG in low-latitude, but can induce the decrease of MTG in high-latitude regions.  相似文献   

17.
The redox sensitive elements, molybdenum (Mo) and uranium (U), in marine sediments from the latest Permian Dalong (大隆) Formation at the Shangsi (上寺) Section, Northeast Siehuan (四川), South China, were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) to determine their response to a range of redox conditions, and to estimate the organic carbon burial rate. On the basis of the correlation between authigenic Mo abundance and organic carbon content in modern oceans, the organic carbon burial rates were calculated for the rocks at Dalong Formation, ranging from 0.48-125.83 mmol/(m2-d), which shows a larger range than the mineralization rate of organic carbon at the continental margins (1.6-4.23 mmol/(m2.d)). The Zr-normalized Mo and U abundances show large fluctuations in the entire section. The maxima of Zr-normalized Mo abundance and thus the maxima of the organic carbon burial rates were observed at the interval between the 155th and 156th beds (404-407 m above the base of Middle Permian). A decrease (the minimum) in U/Mo ratios is present in this interval. It is speculated that the oxygen-limited conditions and ultimately anoxia or euxinia may develop within this depth interval. In contrast, an enhanced enrichment of Zr-normallzed U abundance is found, in association with less enrichment in Zr-normnllzed Mo abundance in the interval from the I51st to 154th beds (395-404 m above the base of Middle Permian), inferring the dominance of a suboxic/anoxic depositional condition (denitrifying condition), or without free H2S. The presence of small quantities of dissolved oxygen may have caused the solubilization and loss of Mo from sediments. It is proposed that the multiple cycles of abrupt oxidation and reduction due to the upwelllng at this interval lead to the enhanced accumulation of authigenic U, but less enrichment of Mo. A decrease in the contents of U, Mo, and TOC is found above the 157th bed (407 m above the base of Middle Permian), in association with the enhanced U/Mo ratio, suggesting the overall oxic conditions at the end of the Dalong Formation.  相似文献   

18.
孙丰英  许光泉  唐文锋 《地下水》2009,31(4):15-17,64
提出采用灰色系统理论中的灰色关联度分析方法对地下水脆弱性进行研究,选取地下水位埋深、包气带岩性、含水层砂层厚度等6个因子建立脆弱性评价指标体系,采用离差最大化方法确定评价指标的权重,使得权重的分配有了一定的理论依据。并以MATLAB为平台编制了常用计算程序,将其应用于抚州市地下水脆弱性评价与分区,取得良好结果。  相似文献   

19.
吉林省城市生态建设现状评价及对比分析   总被引:1,自引:1,他引:1  
建设生态经济城市是吉林省建设生态省过程中的一项重要内容,对我省国民经济和社会发展具有重要作用和意义。本文针对吉林省各主要城市生态建设的基础条件和实际情况,采用层次分析方法构建了包含生态经济、生态环境、社会发展3个子系统32个评价指标因子在内的评价指标体系。应用模糊综合评判法和综合指数法对吉林省9个主要城市从经济水平、产业结构等方面进行了生态建设现状评价,从而为城市生态建设规划等科学决策提供理论依据。  相似文献   

20.
选择信江下游梅港站1950~2010年日径流量,根据流域大型水库界牌枢纽运行时间将梅港站径流序列分为建库前(1953~2001)和建库后(2002~2010)两个时段。采用变动范围法(Range of Variability Approach,简称:RVA)分析水库运行对下游梅港站流域生态水文指标改变度,并分析了信江下游生态流量。研究表明:33个水文指标有22个发生中高度改变,11个指标发生低度改变,其水文综合改变度为0.51,属于中度改变;梅港站生态流量值均在RVA阈值内,基本能够保持河流稳定流量,但2月、7~9月及12月河道生态流量大于RVA下限。可适量增大水库下泄水量,降低对下游河段生态系统的威胁。  相似文献   

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