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141.
长江干流地区区域发展与国家工业化   总被引:1,自引:0,他引:1  
江河流域是人类文明的摇篮。作为四大文明古国之一,江河流域、特别是长江流域(干流)资源的开发对中国的持续发展至关重要。在农耕时期,受气候条件变化的影响,自盛唐中期以后(公元640年)长江流域(干流)就开始取代黄河流域成为国家最重要的人口集聚和社会生产场所。进入工业化进程以来,由于优越的地理位置和良好的人文素质,长江流域(干流)再次承担起推动国家现代经济发展主力引擎的职责,尽管这一发展经受过国家区域发展政策的不同影响。随着国家人地关系演进状态和社会经济整体发展环境的变化,21世纪长江流域(干流)在国家现代化进程中将承担起较以往更为重大的责任,其中以重化工制造业的发展最为重要。然而,要切实完成国家工业化和现代化所赋予的历史使命,长江流域(干流)地区未来的发展应首先处理好自身的发展环境问题,诸如上游地区土壤侵蚀、沿岸城市空气污染、地区能源供应短缺、城乡用地冲突等等。而所有这些问题的解决都依赖于一系列科学的区域发展政策。  相似文献   
142.
There is a critical need for a national agroecosystem model for conservation policy and environmental planning, driven by issues including harmful algal blooms, water scarcity, flooding, and other weather‐related extremes. In this study, we illustrate the feasibility of a national agroecosystem model that will downscale processes to individual fields and first‐order channels. We propose to conceptually divide the conterminous United States (U.S.) into process domains as a framework for simulating processes and management at relevant scales. Specifically, we are proposing five domains: field (1–50 ha), transition (0.2–2.0 km2), headwater (1–15 km2), tributaries (15–150 km2), and main river (>150 km2). The proposed conceptual framework hydrologically connects fields across the U.S. using the National Hydrography Dataset (NHDPlus version 2). Parameterizing the Soil and Water Assessment Tool for the national agroecosystem model resulted in 4,880,000 agricultural fields, 2,250,000 non‐agricultural hydrologic response units, and 7,130,000 transition, 1,610,000 headwater, 591,000 tributary, and 432,400 main channels. Application of this framework was shown for Hydrologic Unit Code 07120002 in central Illinois and Indiana to demonstrate the feasibility of the approach using data that is readily available across the U.S. The new connectivity framework has the potential to dramatically improve national conservation and environmental assessments performed by U.S. Department of Agriculture and U.S. Environmental Protection Agency.  相似文献   
143.
It is generally recognised by the disaster risk management and development communities that disasters have a negative impact on development, and indeed can set back development by years. This realisation led to a new paradigm for the management of hazards and their impacts, namely an integrated approach which emphasises disaster risk reduction being incorporated into national development planning. Awareness, however, does not necessarily translate into implementation. ‘Reduce the underlying risk factors’, Priority for Action 4 of The Hyogo Framework for Action 2005–2015, reported the lowest average score for progress of the five priority areas. Challenges to progress, as reported by Governments included inappropriate development practices, high levels of poverty and other factors which increase vulnerability. Various authors have recognised the difficulty of consistently and successfully integrating disaster risk reduction into development planning. This integration is particularly challenging for Small Island Developing States (SIDS) which face high exposure to hazards, vulnerable populations and limited resources, often both human and financial. The efforts of Jamaica, a Caribbean SIDS, at integrating disaster risk reduction into national development, and some factors which proved to be important in making progress are presented here. This retrospective paper is written from the perspective of a participant observer and traces developments in disaster risk management over three decades, 1980–2010. Integration and inclusiveness, use of quantitative methods and application of risk assessments are identified as being important in gaining acceptance for disaster risk reduction.  相似文献   
144.
王娜萍  李海萍  张帆 《环境科学》2021,42(6):2721-2729
二次有机气溶胶(SOA)是大气污染的主要成分之一,估算汽车尾气所生成的SOA对交通大气污染治理具有重要意义.本文基于国家干线公路交通量调查数据,根据监测站点和代表路段长度建立了中原城市群干线路网线性参考系统,并以车流量为基础数据,采用排放系数法测算出中原城市群干线道路VOCs排放量,再根据气溶胶生成系数对SOA的生成潜势进行估算,并经核密度计算后转换为线性连续分布,进行交通SOA的空间定量分布研究.结果表明:①甲苯的SOA生成潜势最高,但1,4-二乙基苯的SOA生成能力最强,芳香烃的SOA生成能力总体高于烷烃;②中小型汽油客车是最大的SOA生成源,占SOA生成量的1/3左右,但SOA生成能力最强的是小型汽油货车;③汽油车的SOA生成能力高于柴油车,客车的SOA生成能力略微高于货车;④中原城市群的SOA排放强度具有明显的以郑州为中心的高强度聚集现象,汽油车的分布与总体相似,但柴油车的强度和聚集性明显下降,以郑州为中心,南北干线上的排放强度高于东西方向.  相似文献   
145.
松嫩平原西部湿地自然保护区保护有效性遥感分析   总被引:6,自引:0,他引:6  
以松嫩平原西部国家级湿地自然保护区为研究对象,以Landsat MSS/TM/OLI遥感影像为基础信息源,综合运用最小均方差、变异系数、景观指数、信息熵模型、地理信息系统空间分析和景观发展强度指数,研究保护区保护有效性变化及其影响因素.结果表明:松嫩平原西部国家级湿地自然保护区保护有效性大致呈递减趋势;1987~2013年人类活动对保护区的干扰强度不断增加,且与保护区保护有效性呈显著负相关;耕地和草地为湿地转出的主要类型,分别占总转出面积的63.71%和21.69%;湿地自然保护区保护有效性的降低是自然环境变化和人类活动影响共同作用的结果,自然环境变化是内因,而人为活动干扰,尤其是开垦造田和水利修建加速了湿地退化.最后,论文就研究中存在的不足以及保护区管理建设中应关注的问题进行了阐述.  相似文献   
146.
基于全国空气质量监测网数据,分析了2015-2019年汾渭平原11个城市臭氧(O3)污染状况.结果 表明:2015-2019年,汾渭平原11个城市O3平均浓度总体呈升高趋势,年平均升高12.2 μg/m3,其中,2017-2019年均超过二级标准限值(160μg/m3).O3单项污染物的空气质量分指数占空气质量指数的比...  相似文献   
147.
Land degradation by soil erosion is a socioeconomic and environmental problem facing many developing countries. Application of stonewall terraces for soil moisture conservation is vital to reducing the environmental impacts of this phenomenon. To this end, a field plot experiment was conducted in the study area along with the use of a closed-ended questionnaire. The object of the experiment was to study the socioeconomic impacts of soil erosion on local farmers and their adoption of the stonewall terrace technique. The study showed a higher net profit in areas that had implemented terrace conservation practices than in areas that had not (i.e., 3.5 to 6 times higher net profit). Correlation analysis indicated that the farmers’ perceptions, land ownership, and geomorphology were significantly related to the farmers’ incentives and willingness to adopt terraces as soil conservation measures (P < 0.05), although the correlations were negative. Smallholder farmers (52% of the interviewed farmers) were involved in the sale of the agricultural land for urban uses, largely because of the high price and immediate returns offered. However, the associated land use changes warrant greater involvement of both the private and public sectors. This cooperation may be accomplished through the introduction of a long-term agricultural loan system and the development of proper legislation accompanied by a comprehensive and durable infrastructure and service system with the goal of reducing the negative impact of land use changes and encouraging sustainable use of resources.  相似文献   
148.
There is no universally-accepted definition of tourism carrying capacity(TCC).Numerical TCC focuses on use level and is considered as"a magic number"of the saturation point for tourism.There are several reasons why numerical tourism capacity is inadequate.Alternatively,tourism capacity can be defined in terms of limits of acceptable change,which shifts the focus from"how much use is too much"to"how much change is acceptable".This article proposes an improved conceptual framework for evaluating carrying capacity for the tourism city based on approaches used in US national parks,which consider the impact of human use on a city's economic,environmental/resource,and socio-cultural conditions.Based on the basic data of indicator values and relevant standards,the framework monitors the current indicators and predicts future indicator values; it can also be used to assess and predict TCC.  相似文献   
149.
建设秦岭国家中央公园的探究   总被引:1,自引:0,他引:1  
杨亭  丁艳平 《资源开发与保护》2012,(5):475-478,F0003
通过对秦岭的综合分析,借鉴国外"国家公园"的建设经验,从秦岭目前开发现状存在的问题及其原因进行分析研究,提出应成立国家秦岭管理局,科学开发保护秦岭,分不同区域建设秦岭国家中央公园;在发展生态旅游的同时,积极整合资源,争取加入世界人与生物圈,联合申遗,推动秦岭走向世界,从而实现秦岭地区人与自然的可持续发展。  相似文献   
150.
根据上海市空气自动监测网络由市级中心站负责子站和区/县级监测站自建子站共同组成和两级管理的结构特点,上海自2006年开始实施对空气自动监测子站的年度质保审核,并在实践中持续改进和完善。以上海为例对新环境空气质量标准实施和AQI实时发布背景下完整的空气质量自动监测QA/QC体系中的质保审核的建立实施及其效果进行讨论。  相似文献   
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