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991.
西部大开发中的生态安全问题   总被引:12,自引:0,他引:12       下载免费PDF全文
正确处理区域发展与生态安全是西部开发战略的关键。以可持续发展为目标的区域空间结构理论 ,分析了在新一轮科技革命和产业革命的新形势下推动区域发展和区域空间结构演变的决定性因素 ,以及实行效益原则与社会公平原则相统一的必要性 ,从中引出西部大开发中确保生态安全的极端重要性。并就实现区域发展与生态安全的双赢目标所必须建立的能力体系和制度体系提出了建议。   相似文献   
992.
Zink, Jason M., Gregory D. Jennings, and G. Alexander Price, 2012. Morphology Characteristics of Southern Appalachian Wilderness Streams. Journal of the American Water Resources Association (JAWRA) 48(4): 762‐773. DOI: 10.1111/j.1752‐1688.2012.00647.x Abstract: Watersheds without urbanization or impacts from logging are rare in the southern Appalachian Mountains. The Joyce Kilmer/Slickrock Wilderness of North Carolina and Tennessee contains 24 km2 of old‐growth forest, with the balance of the wilderness in a mature second‐growth forest. The watersheds of Little Santeetlah and Slickrock Creek are located within the wilderness. Morphological information, including channel dimensions and longitudinal profiles, was gathered from 14 alluvial stream reaches in these watersheds. The study sites had drainage areas from 0.25 to 41.6 km2 and stream slopes from 0.014 to 0.104 m/m. Bankfull cross‐section dimensions of the study stream reaches were strongly correlated to drainage area across the observed range of slopes and bed morphology. Cross‐section area and width relationships for the streams in this study did not differ significantly from regional curves for the mountain physiographic region of North Carolina. Observations of these reaches did not suggest a definitive rule regarding the proportion of steps and riffles in streams. Pools occupied greater than 50% of the length in all stream reaches with slopes less than 0.07 m/m. Significant correlation existed between step height ratio and slope, suggesting that step height can be approximated as the product of channel width and slope. Riffle length and riffle slope ratios were also significantly correlated with slope, though pool spacing was not.  相似文献   
993.
There are many problems in the minority regions of western Sichuan Province,such as serious soil erosion,fragile ecological environment,low levels of economy and so on.Ad- vantages of tourism resources in theperiphery regionsshould be fully utilized,andmulti-tourismmeets the characteristics and present situation of the minority regions.Themulti-tourism de- velopment modelcan exert the functions of tourism as the key industry.Based on the demands and the internal linkages among different industries,the mo...  相似文献   
994.
依据火灾风险评估方法,对厦门市某区域建立区域火灾风险评估指标体系,运用层次分析法(AHP)进行火灾风险等级评定,依托LINGO软件对该区域内的消防站布局规划进行优化,将原来规划的9个消防站优化为7个,并最终应用于该区域的消防规划工作,促进了消防资源的合理配置,提高了消防资金投入的使用效能。  相似文献   
995.
With the implementation of reform and opening-up, the overall economy of China has made brilliant achievements; meanwhile, however, the economic disparity has been enlarging among some regions, and between the city and the countryside. The existence and evolution of this kind of economic disparity is concerned with social stability, sustainable development and the construction of harmonious society, which has gradually become the hotspot in social economic development. The West Coast of the Strait (WCS) located in southeast littoral areas is adjacent to the Pearl and Yangtze River Delta in the south and north and faces Taiwan Province in the east. The stability and development of this region has vital political and economic meaning in the social economic development of our country. It has important theoretical meaning and practical value to research the form, characteristics and evolution of regional economic disparity in the WCS. Based on insightful analysis on existing study results on the WCS, the paper defines the connotation and extension. By a series of absolute and comparative relative evaluation indexes and taking the WCS since 1992 as the study object, the paper makes analysis on different scales including three regions, four regions, 20 cities and 152 counties, quantitatively evaluates the level, characteristics and evolution of the regional economic disparity and compares the regional economic disparity on different scales. The main conclusions are as follows: the variation trend of the absolute disparity of the whole region is obvious and stable, which has presented an inflating trend; the comparative variation trend on a large scale has waved, The comparative disparity of the three regions increased annually from 1992 to around 2000, which had a decreasing trend from around 2000 to 2005; the comparative variation trend on a small scale was not stable, which showed an annual increase of four regions, 20 cities and 152 counties from 1992 to around 2003 and a decrease from around 2003 to 2005; the  相似文献   
996.
Abstract: Following creation of the 2010 Biodiversity Target under the Convention on Biological Diversity and adoption of the United Nations Millennium Development Goals, information on status and trends of biodiversity at the national level has become increasingly important to both science and policy. National red lists (NRLs) of threatened species may provide suitable data for reporting on progress toward these goals and for informing national conservation priority setting. This information will also become increasingly important for developing species‐ and ecosystem‐based strategies for climate change adaptation. We conducted a thorough global review of NRLs in 109 countries and analyzed gaps in NRL coverage in terms of geography and taxonomy to determine priority regions and taxonomic groups for further investment. We then examined correlations between the NRL data set and gross domestic product (GDP) and vertebrate species richness. The largest geographic gap was in Oceania, followed by middle Africa, the Caribbean, and western Africa, whereas the largest taxonomic gaps were for invertebrates, fungi, and lichens. The comprehensiveness of NRL coverage within a given country was positively correlated with GDP and negatively correlated with total vertebrate richness and threatened vertebrate richness. This supports the assertion that regions with the greatest and most vulnerable biodiversity receive the least conservation attention and indicates that financial resources may be an integral limitation. To improve coverage of NRLs, we propose a combination of projects that target underrepresented taxa or regions and projects that provide the means for countries to create or update NRLs on their own. We recommend improvements in knowledge transfer within and across regions as a priority for future investment.  相似文献   
997.
Abstract

The purpose of this article is to classify the regional economic types and development dynamics of small towns in suburb Beijing by applying the classification methods developed by Nelson’s method and Location Quotient method into 183 small towns in Beijing. Four types of small towns are thus identified, including urban agriculture dominated towns, manufacturing dominated towns, service industry dominated towns and comprehensive type towns with balanced economic development. Within the environment of geographical information system, the spatial distribution pattern of four types of small towns with their evolution trend is analyzed. The results indicate that four types of small towns have obvious ‘core-periphery’ spatial structure but with different functional orientations and evolution mechanisms. Based on this, the different development strategies for each type of small towns are summarized, providing a scientific reference for the differentiating planning and development strategies of these small towns.  相似文献   
998.
以沪苏通三地为例,研究了三地之间产业经济一体化的时间和空间过程,从空间相互作用理论视角探讨了地区之间的互补性、可运输性和介入性等因素的影响机制。研究认为改革开放以来沪苏通三地构成的三角区产业经济一体化经历了由弱到强、简单到复杂的关系,特别是2005年以后,在区域竞争和合作的大背景下,上海藉由定位转向和结构升级重塑区域地位的战略取向使得沪苏通三地产业经济关系步入了一体化重构轨道。三地之间未来要形成3边均强的网络化的产业经济一体化格局,应通过加强地区之间的合作,放大各地之间的互补性,通过减少地区之间非理性的竞争,改善地区之间空间分割。  相似文献   
999.
围绕现行的GB12348—2008《工业企业厂界环境噪声排放标准》在厂界噪声测量中测量指标不明确、方法简单、测点位置未细化等问题,通过对增压站、集输站等进行厂界噪声测量,对存在问题进行分析探讨,提出解决这些问题的方法与改进建议。  相似文献   
1000.
根据实地考察,采集了阿尔金山保护区主要地表水体的水质样本。受考察期限和水质样本保存要求与期限限制,只对样本中铜、锌、镉等重金属指标进行了检测,分析了各指标与《地表水环境质量标准》中不同标准限值的关系,及其在地理空间上的分布规律。本次考察分析的结果可作为后期水质考察的背景信息,是进一步开展保护区水环境调查和研究的基础。  相似文献   
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