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101.
资源外交寓于国际地缘政治的长期博弈之中。地缘政治是一国对外交往所要考虑的重要因素之一。本文立足于内线周边和外线外围的地缘关系分析,总结了中国资源外交地缘政治的总体态势和潜在风险,并试图提出我国资源外交的基本思路。在全球地缘政治格局中,中国的资源外交包括内线地带和外线地带两个层次:内线由接壤的邻国以及接近的近邻组成,是中国资源外交的战略依托地带;外线由涵盖美洲、欧洲、非洲和澳洲大陆的资源生产大国和消费大国组成,是中国资源外交的战略腾挪空间。在这两个层次上,我国的地缘风险主要来自其他大国的地缘战略遏制、“走出去”战略的地缘选择权旁落、资源通道和贸易路线受制于人。要突破这些地缘限制与束缚,我国的资源外交需统筹国内、国际两个大局,分清内线、外线战略方向的轻重缓急,以周边关系为首要、以大国关系为关键、以发展中国家关系为基础,积极拓展对外友好关系的发展空间,有序扩展资源合作领域,坚定维护国家资源权益。  相似文献   
102.
结合陕西灞源地区金矿预测实例,探讨了在蒙特卡罗法应用中潜在矿床总数估计及资源总量概率分布向资源潜力分布转换两个环节的合理实现方法。在一定条件下,矿点空间分布模型和发现过程模型可有效地用于估计潜在矿床总数。通过坐标平移或求截尾分布而将资源总量的概率分布转变为资源潜力的概率分布,可得到较为符合地质实际的评价结果。  相似文献   
103.
Drought is a natural phenomenon posing severe implications for soil, groundwater and agricultural yield. It has been recognized as one of the most pervasive global change drivers to affect the soil. Soil being a weakly renewable resource takes a long time to form, but it takes no time to degrade. However, the response of soil to drought conditions as soil loss is not manifested in the existing literature. Thus, this study makes a concerted effort to analyze the relationship between drought conditions and soil erosion in the middle sub-basin of the Godavari River in India. MODIS remote sensing data was utilized for driving drought indices during 2000–2019. Firstly, we constricted Temperature condition index (TCI) and Vegetation Condition Index (VCI) from Land Surface Temperature (LST) and Enhanced Vegetation Index (EVI) derived from MODIS data. TCI and VCI were then integrated to determine the Vegetation Health Index (VHI). Revised Universal Soil Loss Equation (RUSLE) was utilized for estimating soil loss. The relationship between drought condition and vegetation was ascertained using the Pearson correlation. Most of the northern and southern watersheds experienced severe drought condition in the sub-basin during 2000–2019. The mean frequency of the drought occurrence was 7.95 months. The average soil erosion in the sub-basin was estimated to be 9.88 t ha?1 year?1. A positive relationship was observed between drought indices and soil erosion values (r value being 0.35). However, wide variations were observed in the distribution of spatial correlation. Among various factors, the slope length and steepness were found to be the main drivers of soil erosion in the sub-basin. Thus, the study calls for policy measures to lessen the impact of drought and soil erosion.  相似文献   
104.
The Beijing-Tianjin-Hebei (BTH) region is an important engine for China’s socioeconomic development. Timely and effectively assessing constraint factors of resources and environment is of great significance for the sustainability assessment and the sustainable development of this region. However, comprehensive assessment research considering key resource and environmental constraints are still lacking. In this study, therefore, the limiting factors of resources and the environment in the BTH region were assessed based on the framework of landscape sustainability science. First, we chose five limiting factors, including topographic condition, geological environment, water resource, land resource, and atmospheric environment, to assess the constraints of resources and the environment using the single-factor evaluation method and the multi-factor comprehensive evaluation method. Based on the results, we divided the whole region into five subregions, i.e., the ecological conservation subregion, the geological disaster subregion, the water resource scarcity subregion, the atmospheric pollution subregion, and the cropland protection subregion. The results revealed that the northern BTH region was highly constrained by topographic conditions, the central BTH region was strongly constrained by geological environment and water resources, whereas the southern BTH region was constrained mainly by land resources and atmospheric environment. In addition, water resource was the main limiting factor for regional population growth and economic development. In 2010, the water resource scarcity subregion had a total population of 39.59 million, an urban population of 76.90%, and a gross domestic product of 2 455.57 billion yuan. We argue that the sustainable development of the BTH region should explicitly consider the resource and environmental limiting factors, implement land use optimization according to local conditions, maintain multiple land use types and diverse management strategies, based on the perspective of “strong sustainability”, so as to promote the regional sustainable development.  相似文献   
105.
New Zealand's policy goal to preserve coastal natural character was first incorporated into planning legislation in 1973 and protected area legislation in 1977. An evaluation of 100 relevant Resource Management Act Court decisions determined the Courts' interpretations of this policy goal. The Courts have repeatedly found that natural character is of nature (not culture), including natural elements, patterns, and processes. There is a continuum of naturalness from pristine indigenous ecosystems to the urban environment. A 2014 Supreme Court decision has upheld the use of environmental bottom lines for natural character and the importance of protection as part of sustainable management.  相似文献   
106.
Accurate pesticide exposure estimation is integral to epidemiologic studies elucidating the role of pesticides in human health. Humans can be exposed to pesticides via residential proximity to agricultural pesticide applications (drift). We present an improved geographic information system (GIS) and remote sensing method, the Landsat method, to estimate agricultural pesticide exposure through matching pesticide applications to crops classified from temporally concurrent Landsat satellite remote sensing images in California. The image classification method utilizes Normalized Difference Vegetation Index (NDVI) values in a combined maximum likelihood classification and per-field (using segments) approach. Pesticide exposure is estimated according to pesticide-treated crop fields intersecting 500 m buffers around geocoded locations (e.g., residences) in a GIS. Study results demonstrate that the Landsat method can improve GIS-based pesticide exposure estimation by matching more pesticide applications to crops (especially temporary crops) classified using temporally concurrent Landsat images compared to the standard method that relies on infrequently updated land use survey (LUS) crop data. The Landsat method can be used in epidemiologic studies to reconstruct past individual-level exposure to specific pesticides according to where individuals are located.  相似文献   
107.
扎龙保护区丹顶鹤栖息地适宜性评价   总被引:1,自引:0,他引:1  
结合TM影像和ENVISAT ASAR(HH/HV)数据,以扎龙保护区丹顶鹤栖息地为研究对象,在分布式定量提取评价因子(植被类型、生境结构、巢下水深、植被盖度、人为干扰)的基础上,建立HSI模型对丹顶鹤栖息地质量进行评价,并根据实测巢址空间分布情况对评价结果进行验证。结果表明:基于主观专家知识建立的HSI模型得到丹顶鹤高适宜栖息地面积为48km2,适宜栖息地面积为265km2,低适宜栖息地面积为385km2,不适宜栖息地面积为1 403km2,结合实测数据验证,得出高适宜、适宜和低适宜栖息地巢址共占实测巢址的92.86%,不适宜栖息地巢址占7.14%。经检验HSI模型对淡水沼泽湿地典型水禽栖息地的质量评价有良好的适用性。  相似文献   
108.
Observations from 560 weather stations in China show that sand–dust storms occur most frequently in April in north China. The region consists of Sub-dry Mid Temperate, Dry Mid Temperate, Sub-dry South Temperate and Dry South Temperate Zones and much of the land surface is desert or semi-desert: it is relatively dry with minimal rainfall and a high annual mean temperature. In most regions of China, the annual mean frequency of sand–dust events decreased sharply between 1980 and 1997 and then increased from 1997 to 2000. Statistical analyses demonstrate that the frequency of sand–dust storms correlates highly with wind speed, which in turn is strongly related to land surface features; on the other hand, a significant correlation between storm events and other atmospheric quantities such as precipitation and temperature was not observed. Accordingly, land surface cover characteristics (vegetation, snowfall and soil texture) may play a significant role in determining the occurrence of sand–dust storms in China. Analysis of Normalized Difference Vegetation Index derived from National Oceanic and Atmospheric Administration and Empirical Orthogonal Function show that since 1995 surface vegetation cover in large areas of Northern China has significantly deteriorated. Moreover, a high correlation is shown to exist among the annual occurrence of sand–dust storms, surface vegetation cover and snowfall. This suggests that the deterioration of surface vegetation cover may strongly influence the occurrence of sand–dust storms in China. Soils with coarse and medium textures are found to be more associated with sand–dust storms than other soils.  相似文献   
109.
1:150万山东省地下水资源评价空间数据库,是全国地下水资源评价空间数据库的重要组成部分,是在新一轮山东省地下水资源评价的基础上建立的。本文简要论述了建库的准备、图形数据采集、属性数据采集、数据的集成4个阶段的工作方法流程。该库的建立,实现了山东省地下水资源评价空间信息的集中管理、数据的网络查询、统计分析及全国范围内的信息共享。  相似文献   
110.
本文将Fuzzy综合评判方法应用于建设项目的大气环境影响评价,并通过与其它评价方法的比较,说明Fuzzy综合评判方法在建设项目大气环境影响评价中的可行性和客观性。  相似文献   
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