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101.
达建文 《石油化工技术经济》2005,21(1):25-29
近年来我国原油进口数量急剧增加。石油安全问题引起广泛关注。而我国煤炭与天然气资源相对比较丰富。统筹规划并合理利用煤、油、气资源,通过煤化工、石油炼制、石油化工3个行业技术上的互相借鉴,资源上的互相替代,产业链的互相补充,尽量减少石油的消耗,以减轻对进口原油的依赖。 相似文献
102.
某燃气公司一段埋地高压天然气输送管线某处发生严重破损,为分析失效原因,作者采用宏观形貌分析、扫描电镜分析、化学成分分析、显微组织分析、力学性能检验、Fluent模拟分析等系列方法对该失效管段进行分析。结果表明,与该天然气管近距离平行铺设的自来水供水管道破裂,导致高速水流正面与切向冲刷作用,最终导致天然气管破裂。根据分析结论,提出了预防同类事故发生的建议。 相似文献
103.
Heidi Karst 《Journal of Sustainable Tourism》2017,25(6):746-762
Common definitions of ecotourism address the need to benefit the well-being of local people; in reality, ecotourism is often supported or dominated by external agents. Local ideological, social and cultural values may be overlooked, thereby disenfranchising local and indigenous stakeholders. This paper examines indigenous perceptions of ecotourism and well-being, and how they relate to ecotourism practices in three Brokpa communities of the first protected area in Bhutan to become a special tourism destination. A range of methods (e.g. semi-structured interviews, participatory mapping) was used and data analysis was couched in the context of buen vivir (living well), an indigenous concept of well-being. Findings indicate that: (1) perceptions of ecotourism vary between community members and contrast with the official park definition; (2) well-being is conceived in diverse ways but corresponds to key features of buen vivir; (3) indigenous worldviews are pervasive, and shape social values and spiritual beliefs in connection to nature; and (4) indigenous cosmologies and traditional values may be strengthened through their integration into modern policies and institutions. This research contributes more non-Western voices to the literature, a concept and mode of analysis for well-being that embraces an indigenous ontology, and empirical insights on indigenous communities in protected areas. 相似文献
104.
Recreation carrying capacity (RCC) is one of the most important indictors used in measuring the usage limits for the forest park resources. However, the consensus has not been reached with respect to the RCC’s content and its measuring metrics. In this paper, we attempt to establish a new RCC theoretical framework based on the demand theory of the tourism product characteristics. In the process, the choice experiment and orthogonal design methods are used in questionnaire designs and the conditional Logit model is used for parameter estimates. More than 700 park visitors are surveyed for data collection at the Shenyang National Forest park of Liaoning province in China. The primary park attributes being considered encompass vegetation, coverage, water quality, number of rubbish on the park trail path, admission fees, and congestion. The carrying capacity threshold for each specific attribute is identified. 相似文献
105.
[目的]粮食生产能力关系到粮食供给和国家粮食安全,如何提高粮食生产能力是我国亟待解决的问题。文章以宾县为例,通过一定的方法探索粮食生产能力的影响机制,最终提出提高粮食生产能力的合理建议。[方法]利用农户调查数据,借助Logistic模型探讨自然因素和社会经济因素对粮食生产能力的影响特点。[结果](1)品种技术推广、作物收益对粮食生产能力的影响效应在1%水平上达到显著;(2)生育期变化、土地质量、旱灾、耕作方式对粮食生产能力的影响效应在5%水平上达到显著;(3)温度、降水、冷害及农业生产资料投入对粮食生产能力的影响效应在10%水平上达到显著;(4)温度与降水是否集中在生育期内、出售情况、农业引导政策对粮食生产能力的影响不显著。[结论]针对研究结果,该文提出,可从预防低温冷害、健全水利设施、完善耕地保护制度及加强农业基础设施建设等方面提高粮食生产能力。 相似文献
106.
陈志刚 《生态经济(学术版)》2021,(5):171-178
以北部湾城市群为例用三维生态足迹模型、偏最小二乘法、空间计量模型分析了其自然资本利用状况、空间相关性、驱动因素。结论:(1)城市群自然资本利用处于不可持续状态;(2)自然资本利用程度划分为低、中、高三类,城市也相应分成三类;(3)自然资本利用的主要驱动因素是人口因素、社会经济;(4)空间分析显示全局莫兰指数为正,空间集聚显著,表明自然资本利用存在空间正相关;空间误差模型拟合度最好,并证明自然资本存量占用与人口总量正相关,与GDP总额负相关。 相似文献
107.
自然资产负债表是自然资源管理研究的一个新方向,水资源会计是自然资产负债表的一个重要范围,水资源会计是从资产负债表的角度来分析和统计水资源。研究对水资源会计在国内外研究发展进行了回顾,分析了在中国开展水资源会计理论与应用研究的必要性。研究进一步对水资源会计的理论构架从会计目标、会计主题和会计理论等进行了探讨,明确了水资源会计容易混淆的概念。结合秦巴山区的情况,提出在秦巴山区实现水资源会计的具体步骤。 相似文献
108.
110.
In the 1990s, the Democratic People’s Republic of Korea (North Korea) suffered from severe food shortages and large-scale deforestation, which triggered a stage of rural conservation reform. Since 2004, with support from the Swiss Agency for Development and Cooperation (SDC), North Korea’s Ministry of Land and Environmental Protection (MoLEP) has implemented a Sloping Land Management Program (SLMP). The SLMP established sloping land user groups and granted these groups the right to use marginal land for agroforestry development. This devolution of land rights from state control onto local groups is a landmark in North Korea, and this decentralization initiative has now expanded to over eight counties to involve thousands of households. It has also led to the launch of a National Agroforestry Policy and Strategy. Drawing from both qualitative and quantitative data collected from 2008 to 2014, this paper documents the process and effects of the SLMP. It argues that the decentralization reform in land management has contributed to not only food security with increased food crop diversity and productivity, but also notably forest recovery through an expansion of tree plantations and agroforestry practices on degraded sloping lands. However, an insufficient power transfer in the form of a lack of timber rights granted to the local user groups has hampered the effectiveness of the SLMP. There are also institutional and geopolitical challenges that are limiting further scaling-up of land-use decentralization across the country. The policy implication calls for more international investment as well as national land-use policy reforms in order to promote and facilitate further decentralization of sloping land management and to secure greater use rights for sloping land user groups. 相似文献