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121.
ABSTRACT: It has been well established that the greenhouse gas loading of the atmosphere has been increasing since the mid 19th century. Consequently, shifts in the earth's radiative balance are expected with accompanying alterations to the earth's climate. With these anticipated, and perhaps already observable, changes in both global and regional climate, managers of regional water resources seek insight to the possible impacts climate change may have on their present and future water supplies. The types and degrees of impacts that climate change may have on New York City's water supply system were assessed in a study of a watershed at Allaben, New York. Hypothetical scenarios of future climate and climate change projections from three General Circulation Models (GCMs) were used in conjunction with the WatBal hydrological model and the Palmer Drought Severity Index (PDSI) to ascertain how runoff and soil moisture from this watershed may change in a warmer climate. For the worst case predictions, the results indicate that within the century of the 2000s, the watershed's air temperature may increase up to about 11°F, while its precipitation and runoff may decrease by about 13 and 30 percent, respectively. If this watershed is typical of the others within the New York City water supply system, the system's managers should consider implementing mitigation and adaptation strategies in preparation for the worst of these possible future conditions.  相似文献   
122.
新亚欧大陆桥新疆段环境灾害的灰色拓扑预测   总被引:6,自引:0,他引:6  
基于灰色系统理论中拓扑预测的理论方法 ,对新亚欧大陆桥新疆段环境灾害造成的受损长度进行了分析预测 .在对受损长度时序分布特征分析的基础上 ,给定一组阈值 ξi,并按不同的时间序列分别建立 GM(1.1)模型而得到模型群 .然后应用新亚欧大陆桥新疆段 38年(1959~1997年)的受损长度统计资料 ,对所建模型群进行了检验 ,并用此模型群对未来可能出现一定阈值范围内受损长度的年份进行了预测 .经检验 ,该模型群的原点误差范围为 0.090~6.520 ,精度范围为 72.658~ 97.134.结果表明 ,所建模型群精确度高 ,科学性较强 ,具有比较好的实用性 .  相似文献   
123.
Hurricanes devastated the Gulf coast of the USA in 2005. Hurricane Katrina, in particular, highlighted the compelling need to build more sustainable and hazard-resilient communities. Much can be learned from recovery efforts to rebuild the Gulf coast. Personal observations and interviews with planners, academics and others involved in recovery efforts inform this analysis, which focuses on New Orleans. A conceptual framework is developed and principles and operational imperatives outlined to guide action for building sustainable, hazard-resilient communities. Such communities will remain elusive unless ‘business as usual’ is confronted by a transformational process of developmental planning. Sustainable, hazard-resilient coastal communities are founded upon robust ‘critical infrastructure’ that is secured by planning and decision-making processes that enable coastal communities to build ‘layers of resilience’ to overcome ‘waves of adversity’. Planners need to take on a redefined role—as ‘new naval architects’—to design and build communities that are ‘sea-worthy’ in this age of coastal storms.
Bruce C. GlavovicEmail:
  相似文献   
124.
霍雨  王腊春 《四川环境》2007,26(2):79-83,100
党的十六届五中全会提出了新农村建设的任务,江苏省也于近期举办了新农村建设专题研讨会。本文通过对现存相关指标体系的回顾分析,结合新农村建设“生产发展、生活宽裕、乡风文明、村容整洁、管理民主”的内涵,对江苏省新农村建设指标体系进行了初步探讨,并采用这一体系对大丰市南阳镇新农村建设实现程度进行了评价。结果表明,虽然江苏省农村发展水平已有明显提高,但仍需要进一步加强农村工作,努力达到新农村建设的目标。  相似文献   
125.
浅论农业可持续发展的新模式:资源循环型农业   总被引:7,自引:1,他引:7  
阐述了资源循环型农业的基本概念及其特征,根据循环经济的相关理论和国内外农业发展的实际情况,指出我国农业应在生态农业的基础上,朝着资源循环型农业的目标发展。  相似文献   
126.
A multivariate statistical technique, cluster analysis, was used to assess the logged surface water quality at an irrigation project at Al-Fadhley, Eastern Province, Saudi Arabia. The principal idea behind using the technique was to utilize all available hydrochemical variables in the quality assessment including trace elements and other ions which are not considered in conventional techniques for water quality assessments like Stiff and Piper diagrams. Furthermore, the area belongs to an irrigation project where water contamination associated with the use of fertilizers, insecticides and pesticides is expected. This quality assessment study was carried out on a total of 34 surface/logged water samples. To gain a greater insight in terms of the seasonal variation of water quality, 17 samples were collected from both summer and winter seasons. The collected samples were analyzed for a total of 23 water quality parameters including pH, TDS, conductivity, alkalinity, sulfate, chloride, bicarbonate, nitrate, phosphate, bromide, fluoride, calcium, magnesium, sodium, potassium, arsenic, boron, copper, cobalt, iron, lithium, manganese, molybdenum, nickel, selenium, mercury and zinc. Cluster analysis in both Q and R modes was used. Q-mode analysis resulted in three distinct water types for both the summer and winter seasons. Q-mode analysis also showed the spatial as well as temporal variation in water quality. R-mode cluster analysis led to the conclusion that there are two major sources of contamination for the surface/shallow groundwater in the area: fertilizers, micronutrients, pesticides, and insecticides used in agricultural activities, and non-point natural sources.  相似文献   
127.
基于生态系统服务供需的雄安新区生态安全格局构建   总被引:2,自引:0,他引:2  
生态安全格局构建是保障区域生态安全的关键。沿用“源地识别—阻力面构建—廊道提取”的生态安全格局构建模式,选取粮食供给、产水量、土壤保持、固碳释氧和生境维持5项生态系统服务供给指标,以及人口密度、地均GDP和土地利用程度3项生态系统服务需求指标,综合生态系统服务供需2方面识别重要生态源地,利用夜间灯光强度进行基本阻力面修正,采用最小累积阻力模型进行生态廊道提取,构建出雄安新区生态安全格局。研究表明:新区生态源地总面积约48433 km2,占新区土地总面积的313%,主要分布于新区西北部旱地和东南部水域;新区生态阻力系数空间分布较为破碎,大部分区域阻力值较低,间或分布高阻力值;新区生态廊道总长度18586 km,呈“Y”字型沿建设用地和水系分布,所处地类主要为旱地。基于生态系统服务供需的生态安全格局构建可为新区规划建设提供参考和借鉴。  相似文献   
128.
Humans’ superiority over all other organisms on earth rests on five main foundations: command of fire requiring fuel; controlled production of food and other biotic substances; utilization of metals and other non-living materials for construction and appliances; technically determined, urban-oriented living standard; economically and culturally regulated societal organization. The young discipline of ecology has revealed that the progress of civilization and technology attained, and being further pursued by humankind, and generally taken for granted and permanent, is leading into ecological traps. This metaphor circumscribes ecological situations where finite resources are being exhausted or rendered non-utilizable without a realistic prospect of restitution. Energy, food and land are the principal, closely interrelated traps; but the absolutely decisive resource in question is land whose increasing scarcity is totally underrated. Land is needed for fulfilling growing food demands, for producing renewable energy in the post-fossil and post-nuclear era, for maintaining other ecosystem services, for urban-industrial uses, transport, material extraction, refuse deposition, but also for leisure, recreation, and nature conservation. All these needs compete for land, food and non-food biomass production moreover for good soils that are scarcer than ever. We are preoccupied with fighting climate change and loss of biodiversity; but these are minor problems we could adapt to, albeit painfully, and their solution will fail if we are caught in the interrelated traps of energy, food, and land scarcity. Land and soils, finite and irreproducible resources, are the key issues we have to devote our work to, based on careful ecological information, planning and design for proper uses and purposes. The article concludes with a short reflection on economy and competition as general driving forces, and on the role and reputation of today’s ecology. Updated version of the keynote lecture presented at the EcoSummit 2007 in Beijing, China, May 24. The article is gratefully dedicated to the memory of my late colleague and friend Frank B. Golley.  相似文献   
129.
长江下游典型滨海地区农业土壤重金属污染特征   总被引:1,自引:0,他引:1  
为揭示长江下游滨海地区农业土壤重金属污染状况,以滨江临海的南通市为例,网格化布点,采集表层农业土壤样品共计334个,对其重金属Cu、Pb、Cr、As、Hg含量进行了测定分析.结果表明,研究区域表层农业土壤中各重金属含量均已超过其背景值,且以Pb污染最为严重;区域性差异较大,以滨海的如东、海门、启东污染最为严重,且以海门、启东As含量最高;各重金属间相关性不显著,来源途径不止一种.从而提出南通市农业土壤重金属污染的防治应立足于防重于治的方针,着重滨海地区,以Pb、As污染源为主,并对污染土壤进行修复.  相似文献   
130.
酸沉降影响稻米品质的新发现   总被引:2,自引:0,他引:2  
酸沉降影响了稻米质量和口感.酸雨时空分布从宏观上概括了稻米品质的地理分布.酸雨决定了酶活性相关金属离子的丰缺,继而影响淀粉合成关键酶的活性,最终影响淀粉合成质量.温度变化是表象,降雨pH值变化是条件,酶活性相关金属离子丰缺是根本,实质是酶活性相关金属离子或激活或抑制了支链淀粉合成关键酶的活性.提出了改善粮食作物质量的化控创新技术路线.  相似文献   
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