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91.
Heat flow and its coalbed gas effects in the central-south area of the Huaibei coalfield, eastern China 总被引:2,自引:0,他引:2
TAN JingQiang JU YiWen ZHANG WenYong HOU QuanLin & TAN YongJie College of Earth Science Graduate University of Chinese Academy of Sciences Beijing China No. Exploration Party of Anhui Bureau of Coal Geology Suzhou Development Research Center China Geological Survey Beijing 《中国科学:地球科学(英文版)》2010,(5)
Based on an analysis of the present geo-temperature field and the thermal conductivity (K) of 62 samples from the central-south area of the Huaibei coalfield in eastern China, we calculated the heat flow and plotted its distribution map. The results show that the average heat flow in the research area is about 60 mW/m2. It is different from other major energy basins in the North China Plate, but has close relationship with the regional geology and the deep geological setting. The heat flow is comparatively ... 相似文献
92.
短期气候预测的现状 问题与出路(一) 总被引:4,自引:0,他引:4
丑纪范 《沙漠与绿洲气象(新疆气象)》2003,26(1):1-4
从方法论上分析了短期气候预测的现状、问题与出路。着重指出:基础理论研究的欠缺又不甚得法是短期气候预测准确率提高缓慢的原因;应当将数值预报的提法从初值问题改为演变问题,进一步提为反问题;统计学方法与动力学方法要相互借鉴,取长补短,融合发展。 相似文献
93.
《环境影响评价技术导则地下水环境》(HJ610-2011)的颁布与实施,对规范煤炭工业建设项目地下水环境影响评价工作,提高地下水环境影响评价的技术水平具有十分重要的意义。然而自导则颁布以来,业内对地下水评价工作的技术难度存在不同的理解,尤其是煤炭行业项目类型较多,对地下水环境的扰动特点及复杂程度不一。从地下水评价的四个方面:分类定级、现状调查评价、影响预测、预防措施逐一进行分析,提出每项工作中常见的问题和难点,并给出相应的理解和建议,期待可以提高地下水评价工作的科学性和合理性。 相似文献
94.
Understanding biogeographic patterns and the mechanisms underlying them has been a main issue in macroecology and biogeography, and has implications for biodiversity conservation and ecosystem sustainability. Evergreen broad-leaved woody plants(EBWPs) are important components of numerous biomes and are the main contributors to the flora south of 35°N in China. We calculated the grid cell values of species richness(SR) for a total of 6265 EBWP species in China, including its four growth-forms(i.e., tree, shrub, vine, and bamboo), and estimated their phylogenetic structure using the standardized phylogenetic diversity(SPD) and net relatedness index(NRI). Then we linked the three biogeographical patterns that were observed with each single environmental variable representing the current climate, the last glacial maximum(LGM)–present climate variability, and habitat heterogeneity, using ordinary least squares regression with a modified t-test to account for spatial autocorrelation. The partial regression method based on a general linear model was used to decompose the contributions of current and historical environmental factors to the biogeographical patterns observed. The results showed that most regions with high numbers of EBWP species and phylogenetic diversity were distributed in tropical and subtropical mountains with evergreen shrubs extending to Northeast China. Current mean annual precipitation was the best single predictor. Topographic variation and its effect on temperature variation was the best single predictor for SPD and NRI. Partial regression indicated that the current climate dominated the SR patterns of Chinese EBWPs. The effect of paleo-climate variation on SR patterns mostly overlapped with that of the current climate. In contrast, the phylogenetic structure represented by SPD and NRI was constrained by paleo-climate to much larger extents than diversity, which was reflected by the LGM–present climate variation and topog-raphy-derived habitat heterogeneity in China. Our study highlights the importance of embedding multiple dimensions of biodiversity into a temporally hierarchical framework for understanding the biogeographical patterns, and provides important baseline information for predicting shifts in plant diversity under climate change. 相似文献
95.
通过对经济建设、资源勘探、环境保护和地学发展的需求分析,提出了进行精细地质研究的必要性,诠释了精细地质的概念及其技术体系。认为精细地质是以先进的技术方法和高灵敏度的测量仪器,对地质体进行精确细致的研究,形成先进、精确、实用的成果,达到提高地学科研与调查水平,高效服务经济建设的目的。精细地质的技术体系包括遥感、物探、化探、钻探、同位素测年、空间定位技术、计算机技术等,通过空中地表地下全方位立体化的综合调查,完成对研究对象的精细研究。通过物探、遥感、同位素测年、化探等核心技术在国内外精细地质研究中的发展应用状况分析,以遥感技术为例,阐述了进行精细地质调查研究的可能性,展望了精细地质在矿产资源勘探、地学研究、环境保护、国防建设、地质灾害调查等领域的应用前景。 相似文献
96.
《Marine Policy》2017
Particulate matter (PM) emissions from ships in ports are a major contributor to air pollution and smog in port cities. The issue of how to reduce PM emissions has become a critical concern for port city residents and governments. This paper establishes an incentive policy to reduce PM emissions from ships in ports. Using a Panamax bulk carrier as a case study, eight alternative approaches that could be adopted by shipping companies are compared and their operational benefits are estimated. By restricting the analysis to emission control areas (ECAs), the net present value (NPV) model shows that the diesel particulate filter (DPF) is the most advantageous approach with the highest NPV, while the exhaust gas scrubber (EGS) approach is the most economically inefficient. Meanwhile, due to DPF's excellent performance in PM abatement, it is suggested that governments should prioritize the DPF approach when promoting the application of emission reduction technologies. From the perspective of social welfare, a positive social benefit of about US $20,000 will be generated over the life cycle of a ship. However, a low government pricing in China will reduce shipping companies’ operational performance as the emission control zone (ECZ) gradually expands. As a result, an appropriate subsidy scheme is necessary to encourage shipping companies to apply emission reduction technologies. 相似文献
97.
近年来,莱芜市莱城区张家洼规模化畜禽养殖发展迅速,促进了当地的经济发展,但畜禽养殖用地的规划还处于无序状态,畜禽养殖破坏了环境,影响了村容村貌。为此,莱城区加强畜禽养殖用地管理,加强规划控制,加强畜禽养殖用地规模的核查;推行畜禽养殖用房流转,收取复耕保证金,走大棚养殖特色之路,取得了明显成效。 相似文献
98.
介绍了适宜山东沿海鱼类增养殖的主要种类 ,回顾了山东省主要海水鱼类增养殖种类研究和生产发展的历史、山东省近年海水鱼类养殖概况。最后论述了今后的发展战略与对策 相似文献
99.
天津大神堂是我国北方纬度最高的现代活体牡蛎群聚海域,区域内地质条件特殊,生物多样性丰富,贝类生物与砂质沉积物等环境因素共同构成了独特活牡蛎礁海洋生态系统。近几年来,受海洋开发、环境污染、过度捕捞影响,牡蛎礁区面积逐年减缩小,生物资源持续衰退,2013年经国家海洋局批准建立了天津大神堂牡蛎礁国家级海洋特别保护区。为加强海洋特别保护区建设,本文分析了天津大神堂海洋特别保护区的自然条件和现状,探讨了健全管理体系,完善法律法规制度,加强生态环境监测,构建兼顾生态效益和经济效益的可持续利用新模式等问题,以期为天津大神堂牡蛎礁国家级海洋特别保护区的养护及管理提供参考。 相似文献
100.
在1996年杭锦旗土地利用调查基础上,分析了土地利用现状、开发程度及经济效益、土地利用中存在的问题等,提出了分区开发治理对策。分区开发治理对策中,重点阐述了土地利用现状、地域分区和生态建设,确定了各分区的用地主导方向,力争建立生态经济型土地利用结构,避免各行业用地矛盾及生态恶性循环的延续。 相似文献