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151.
河南省打造内陆开放高地研究   总被引:1,自引:0,他引:1  
从河南省对外开放态势入手,较详细地分析了近年来尤其是"十一五"期间外部因素对河南省经济发展所起到的促进作用。在此基础上,结合中原经济区建设的新形势,提出为了更好地利用外部因素,需要打造内陆开放高地。根据河南省的优势,河南省内陆开放高地的打造应从以下几个方面展开:承接产业转移,形成产业集聚高地;加快综合保税区建设,形成开放制度创新高地;提高外资利用质量,形成利用外资高地;打造服务外包示范城市,形成服务外包高地。  相似文献   
152.
以山岳型旅游地武夷山风景名胜区为例,估算了风景区景观生态服务价值,分析1986年、1997年、2009年风景区景观生态服务价值时空变化特征,并运用相关分析和逐步回归分析方法对生态服务价值与环境因子的关系进行了探讨,以期揭示风景区景观生态服务价值与环境因子间的作用规律。结果表明:1.武夷山风景名胜区景观类型单位面积生态服务价值最高为水体(9 3707元/(hm2.a)),最低为裸地(354元/(hm2.a)),建设用地价值(12 000元/(hm2.a))仅高于裸地、农田、灌草等景观类型,杉木林、马尾松林、竹林、阔叶林等森林景观服务价值相差不大;2.风景区内景观生态服务价值在1986—1997年间服务价值有较大损失,在1997—2009年间得到一定程度弥补,但1986-2009年间景观生态服务价值变化呈亏损趋势,植被景观类型向建设用地的转变导致景观生态服务价值的降低;3.风景区内景观类型生态服务价值与环境因子(坡向除外)间呈现中等相关性,其中,郁闭度与生态服务价值相关系数最高(0.7**),环境因子中蓄积量与郁闭度相关系数最高(0.86**);4.植被景观生态服务价拟合结果(R2=0.7524,p<0.0001)值优于非植被景观(R2=0.5370,p<0.0001),拟合效果能较好地揭示景观类型生态服务价值与环境因子间的数量关系。  相似文献   
153.
重庆地区年可利用降水资源的变化分析   总被引:6,自引:0,他引:6  
利用重庆地区34站月平均气温及降水资料,在陆面蒸发经验模型基础上计算了可利用降水资源,采用EOF方法分析了主要分布型,并讨论了其变化规律,最后利用MGF-BP神经网络多步预测模型对重庆地区未来10 a(2006—2015年)可利用降水资源进行了预估。结果表明,重庆年可利用降水资源大体分为4种分布类型,即全区域分布型、东西分布型、南北分布型和中部型,其中全区域型是重庆年可利用降水资源最主要的分布型,各分布型具有较显著的年代际变化特征;当年气温偏高、降水量偏少时,年可利用降水资源可能偏少,而当年气温偏低,降水量偏多时,年可利用降水资源可能偏多;初步预测表明,2006—2011年,重庆地区年可利用降水资源总体偏少,而2012—2015年则可能偏多。  相似文献   
154.
北京市海淀区地下水污染风险性评价   总被引:10,自引:0,他引:10  
地下水受污染的风险性主要由含水层本身的防污性能、人为污染源污染地下水的灾害等级和地下水受污染后造成的后果严重程度等因素决定的,地下水污染风险性高是指高价值的地下水资源受到灾害高的污染源的污染可能性大,评价地下水污染风险需要编制3张基础图:地下水易污性图、地下水价值图和地下水污染源灾害分级图。本文介绍并应用了定量评价的DRASTIC方法和定性评价的矩阵方法,定量和定性相结合,综合了含水层易污性、地下水开发利用价值和污染源对地下水影响等因素,对北京市海淀区浅层地下水受污染的风险性进行了综合评价。  相似文献   
155.
SR28、SR29地热对井位于天津市东丽区,处于沧县隆起之大小东庄凸起的西缘,沧东断裂带附近,山岭子地热异常区中心。SR28、SR29地热对井采用中元古界蓟县系雾迷山组热储层作为开采和回灌目的层。根据地热水化学分析结果分析了地热水的水文地球化学特征,认为:SR28、SR29地热水属于含岩盐地层溶虑的陆相沉积水;雾迷山组碳酸盐地层为地热水的储水层,地热水来源于外源水流经上层灰岩地层的补给;SR28、SR29地热水属于未污染的天然水、微腐蚀型水,不结CaCO3垢和CaSO4.2H2O垢,有S iO2垢生成的可能。  相似文献   
156.
新疆幅员广阔,深居内陆,自然复杂,人文多样,是中国旅游资源特丰区。通过组织跨部门,多学科的专家按照《中国旅游资源普查规范》(试行稿)实地考察,对新疆旅游资源的丰度、类型、功能、地域结构给出了新评价,确认它是中国旅游业发展的重要资源后备基地。从新疆地处欧亚大陆腹心,毗邻八国的特殊区位,以及世界旅游重心东移,中国旅游资源开发向内陆推进的多维多元化出发,提出了树立超前意识以市场为导向,深层次,高品位,多元化开发新疆旅游资源的新方略。即确立发展大旅游业的战略观念构建“引爆工程”、“转动效应”的特种旅游、专题旅游和常规旅游项目,完善旅游管理体制,发展以航空运输为主体的综合运输网络,强化旅游软硬件设施,建设能满足不同层次需求、富有特色功能、具有国际意义的国家级旅游地域新网络系统。  相似文献   
157.
New stratigraphic, major- and trace-element, and Sr-, Nd- and Pb- isotopic data on volcanic deposits older than 14 ka from the island of Procida, Italy, are presented and compared with published analyses from the rest of the Phlegraean Volcanic District (PVD). Procida rocks range in composition from basalt to shoshonite and trachyte and show 87Sr/86Sr, 143Nd/144Nd, 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb ratios varying within the ranges 0.70523–0.70678, 0.512539–0.512630, 18.99–19.29, 15.67–15.69 and 39.10–39.39, respectively. The presence of a compositional gap in the range SiO2=54–59 wt % is evidence of magma bimodality, and suggests that the feeding magmatic system was formed by at least two different reservoirs located at different depths. Geochemical and isotopic variations with increasing differentiation can be explained by fractional crystallization mechanisms, that in some cases were associated with crustal contamination that occurred in both deeper and shallower reservoirs; the most evolved magmas formed in the shallower one. Mixing/mingling processes also occurred. The variation of isotopic composition through time observed both for Procida and for Campi Flegrei and Ischia rocks is evidence of strong affinity between magmas that erupted on the entire PVD until about 40 ka. This indicates that they share a common origin and a common plumbing system. Most of the PVD eruptive centers active until about 40 ka lie within a NE-SW-oriented volcano-tectonic belt extending from the southeastern part of Ischia, through Procida and Torregaveta volcano to the northeastern sector of the present Campi Flegrei caldera. This not only indicates the existence of a link between regional structures and volcanism in the area, but also suggests that PVD magma genesis and evolution were strongly regulated by extensional tectonics. In the last 40 ka the mafic rocks erupted along this extensional structure – from Torregaveta and the islands of Ischia and Procida – indicate that it still represents an important crustal discontinuity that focuses mantle-derived magmas. Procida trachybasalts are enriched in large ion lithophile elements (LILE) and light and middle rare earth elements (LREE and MREE), and show slight negative anomalies in the high field strength elements (HFSE) relative to average MORB. A slight depletion in HREE is present. Trace element and isotope systematics can be referred to a lithospheric mantle source. The lithospheric mantle source carries intra-plate and slab-derived components, the latter probably inherited from a previous subduction event.  相似文献   
158.
159.
Soil salinization is mainly an arid-zone problem leading to land desertification. It reduces soil quality and limits the growing of crops. The control of this problem involves inventorying, mapping, and monitoring soil salinity, which requires cost-effective, rapid, and reliable methods for determining soil salinity in the field, and rapid, specific data-processing methods. This paper shows the usefulness of an integrated methodology involving a hand-held electromagnetic sensor (Geonics-EM38) and the ESAP (Electrical conductivity or salinity, Sampling, Assessment and Prediction) software for assessing, predicting, and mapping soil salinity. The salinity of a 0.45-ha surface-irrigated plot was analysed by reading the EM38 at 161 locations, and by employing the ESAP software for calibrating the sensor, and predicting and mapping soil salinity at multiple depths. To calibrate the EM38 sensor, the electrical conductivity of the saturation extract (ECe) of 57 soil samples taken at 19 points was measured. The multiple linear regression (MLR) calibration model predicted ECe from EM38 readings with R2 ranging from 0.71 to 0.95 for the multiple-depth profile. Furthermore, the MLR calibration model provided field range average estimates of soil salinity. Fifty-seven percent of the field had ECe values above 4 dS m−1. The salinity levels and distribution in the root zone identified areas with inverted profiles, which revealed drainage problems. The integrated method presented is a breakthrough in the ability to accurately and rapidly assess soil salinity in agricultural lands.  相似文献   
160.
Highly elevated cadmium concentrations in paddy soil in the Mae Sod District, Tak Province, Thailand, was detected and widely reported in 2003. This emergence provoked public interest and demands for responsibility and remedial actions. As zinc mines and concentrator were located in the upstream area, mining activities were proclaimed a contamination source. Department of Primary Industries and Mines (DPIM), a governmental organization responsible for mining and mineral processing, was thus challenged to verify the reliability of post monitoring data displaying consistently low heavy metal concentrations in compliance with the standard limits for over 15 years. Detailed survey and deep-going research on the causes, boundary and severity of cadmium contamination as well as the environmental impact alleviation were consequently conducted. Environmental samples were accumulated systematically for 2 years throughout the areas of upstream and downstream mining sites. A total of 259 soil samples from 53 spots at the depths of 0-20, 20-40, 40-60 and 60-200 cm were drilled with hand auger. Samples of water, stream sediment and mine tailing were also collected. Chemical analysis for cadmium (Cd), zinc (Zn) and lead (Pb) concentrations with AAS and ICP were undertaken. The contaminated area was finally defined to spread over approximately 18 square kilometer mainly of mountainous mineralizing land and colluvium.  相似文献   
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