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131.
It is a worldwide challenge to explore the deeply buried deposits. Deep-penetrating geochemical exploration methods were developed to solve the problems of how to get the information of the buried deposits in the covered layer. The methods were successfully used to indicate some buried deposits, but not all kinds of deposits. What is more, a method cannot be used in all kinds of landscapes. In this paper, theories and case studies of deep-penetrating geochemical exploration methods, including mobile metal ions, enzyme leach, leaching of mobile forms of metals in overburden, electro-geochemical extraction method, biogeochemical exploration, nano-metal in geogas were reviewed. Elements migration, unloading mechanism and anomaly models are the most important parts for deep-penetrating geochemistry and need to be further investigated. From the perspective of economic efficiency and applicability, sampling and analyzing procedures should be simplified to improve the stability of all methods.  相似文献   
132.
The Spanish real estate boom and bust of the 2000s caused immense economic, social, and environmental changes across the country. Massive urbanization, however, does not necessarily entail the end of nature and natural processes, instead marking a radical transformation of environments and societies. Through a political ecology approach, we analyze how ornamental species have become a fundamental part of new natures induced by urbanization in the Spanish province of Alicante. We connect the economic and ecological characteristics of ornamental plants like the palm tree to urbanization and real estate trends in Alicante. Our evidence indicates that, in Alicante, economic recession and environmental crises (manifested in the pests affecting palm trees) have mutually reinforced one other, creating a new geography of ecological desolation in many areas.  相似文献   
133.
A field study evaluating wetted radius (Wr), downward depth (Dd), and upward movement (Um) under different emitter discharges and lateral depths was conducted. Four emitter discharges (2, 4, 8, and 16 L/h) and four lateral depths (0, 10, 20, and 30 cm) were tested in a clay loam soil. Relationships were found between the emitter discharge and lateral depth versus Wr, Dd, and Um. Wetting area at the surface occurs under different emitter discharges and lateral depths except at 30 cm lateral depth. At lateral depth of 0 and 10 cm, Wr and emitter discharge were positively correlated. The Dd was not affected by emitter discharge except for laterals installed at 20 cm depth. At 30 cm lateral depth, the correlations between each of Wr, Um, and Dd with emitter discharge were poor. The ratios of Wr/Dd and Um/Dd, with respect to emitter position, were less than unity over different emitter discharges and lateral depths. These results shed some light on the design of subsurface drip irrigation scheme so that the spacing between emitters should be determined based on the lateral depths and discharge of emitters. Evaporation losses were negligible for the 30‐cm‐lateral depth since the upward moisture movement has not reached the soil surface area at all discharge rates tested in the study.  相似文献   
134.
杨斌  程紫燕  郑树平 《山西地震》2011,(2):42-45,48
地震发生时,地震应急指挥技术系统在应急基础数据库的支持下,可以迅速判断地震的规模、影响范围、人员伤亡、经济损失等情况。文章对影响计算结果的破坏矩阵、影响场模型等进行了分析,并分别与历史地震震后实际的灾害损失情况进行对比,以找到适合山西地区的本地化模型参数,为地震应急指挥提供科学的参考依据。  相似文献   
135.
Novel information and communication technologies have created new possibilities for transferring information and knowledge over distance. Although this might open up broad options for economic interaction, knowledge regarding the effects of these changes on the geographies of production and innovation is still incomplete. Under these circumstances, permanent co-location and face-to-face (F2F) interaction may be efficient in some contexts but not in others. Support by computer-mediated communication (CMC), temporary, and virtual interaction is increasingly becoming the basis for establishing trans-local production networks. By combining results from social psychology with economic geography, it is argued that there is no generally superior spatial fix for economic interaction. Different spatial configurations can be advantageous in different production and innovation contexts, even over large distances without permanent or even regular F2F contact. This paper systematically investigates the effects of new communication technologies and different organisational forms for economic interaction by emphasizing the potential of combining CMC with forms of temporary and permanent F2F interaction.  相似文献   
136.
加快文旅产业融合发展利于增强国家软实力和满足人民日益增长的物质文化需要。采用2002—2017年长江经济带11省市和三大城市群的73个地级及以上城市截面数据,运用双产业系统的耦合测度模型、相对发展度模型和探索性空间数据分析法,实证分析长江经济带文旅产业融合发展水平及其空间演化特征。研究发现:(1)文旅产业融合发展水平整体趋于上升,但仍属初级融合阶段。文旅产业融合发展水平从下游到中游及上游呈逐步递减趋势。(2)文旅产业融合发展水平及其增速出现空间异质性。中上游地区文旅产业融合发展水平增速较快,并与下游地区的差距有所减小。(3)文旅产业融合发展的空间集聚差异显著。下游地区属于“高-高”集聚区,成为文旅产业融合发展的重要增长极,具有明显的空间扩散效应;中游地区及核心城市属于“高-低”集聚区,正在成为文旅产业融合发展的新增长极;上游地区则需加快打破二者融合发展的 “低-低”集聚区困局。(4)三大城市群间的文旅产业融合发展不平衡。长三角城市群文旅产业的相应综合发展指数明显领先、二者融合发展的“高-高”集聚空间趋于扩大。  相似文献   
137.
以安徽铜陵凤凰山矿田为例,通过综合地质研究,构建了矿体定位预测概念模型。在地质勘探数据和物化探数据集成的基础上,采用三维地质建模技术,对地层、构造、岩浆岩、矿体等地质体进行了推断和圈定,构建了地质体的线框模型与块体模型。基于定位预测概念模型和地质体三维块体模型,通过地质空间定义和立体单元划分,建立了岩体及其表面形态起伏、接触带、地层、褶皱、断层等控矿地质因素的三维栅格场模型。在定量分析控矿地质因素与矿化分布的关系的基础上,建立了反应这种关联关系的矿体立体定量预测模型。预测模型提供矿田深部(-1000m标高以上)所有50m×50m×50m立体单元的铜品位、铜金属量和含矿概率的预测结果。基于预测结果圈定了4个深部找矿立体靶区,为深部找矿工程的设计、布置提供尚未发现的隐伏矿体的位置、品位、金属量等信息的指导。  相似文献   
138.
Special Economic Zones (SEZs) are important vectors of neoliberal globalization in India. Despite facing widespread resistance against the proposed land acquisition for these zones, they are still being promoted across the country. We argue that the wealth redistribution to the country's elites and the fractured resistance movements enable neoliberalism and its practices to grow in the countryside. Using a private sector SEZ in Gurgaon as a case study, this article explores how special economic zoning, as a neoliberal policy, has been implicated in the spatialized production of poverty. We also show that the main actors who promote neoliberalism in India (the state and the large‐scale urban private sector) have found a seemingly unlikely ally in rural India in the form of farmers with large landholdings, rural elites who are willing to let go of their land under certain conditions. The data for the article was collected in India in 2009–10.  相似文献   
139.
中原经济区干线公路路网通达性研究   总被引:1,自引:0,他引:1  
利用GIS空间分析工具,选取最短时间矩阵、最短路径矩阵、路网密度及通达性系数等指标,对中原经济区干线公路路网通达性进行分析。结果表明:中原经济区公路总长度和高速公路长度逐年快速增加,国道和高速公路分别呈现出"四横五纵"和"米"字型布网。郑州、开封、许昌和新乡因优越的干线公路基础条件和中心地理位置,位居公路路网总距离和总时间排名的前列;运城市、蚌埠市和晋城市则因边缘效应而排名相对靠后。郑州和洛阳的交通中心地位明显,特别是郑州的中心地位更加突出,但以二者为中心交通运输最短时间分布状况欠佳,2 h圈内的城市数量较少。研究区总路网密度较高,区域内路网总容量较大,服务能力和辐射能力较强。高密度路网主要分布在中东部,低密度则分布在北部、西部和南部。高通达性城市主要分布在山东省和河南省,低通达性城市主要分布在河北省、山西省、安徽省及河南省部分省辖市,郑州市干线公路通达性最好,蚌埠市最差。自然地理位置、经济发展水平及交通建设资金投入是影响公路路网通达性的主要因素。  相似文献   
140.
Inequalities, institutions, and forest commons   总被引:1,自引:0,他引:1  
This paper contributes to a growing literature on the commons that examines the relationship between inequality and commons outcomes. Our analysis of evidence on forest commons outcomes in 228 cases from South Asia (India and Nepal), East Africa (Kenya and Uganda) and Latin America (Mexico and Bolivia) suggests that local governance and collective action matter in shaping how socioeconomic inequalities affect forest conditions. In particular, we find that both inter-group and intra-group economic inequalities have consistently negative effects on forest outcomes, but that effectively functioning local institutions for collective action dampen the negative effect of inter-group inequality on forest outcomes.  相似文献   
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