黄河流域节水高效农业建设的紧迫性及途径探讨

黄河流域由于水资源短缺,供需矛盾日益尖锐。本文在分析黄河流域水资源开发利用现状与建设高效节水农业紧迫性的基础上,对黄河流域建设节水高效农业的潜力进行了评价,并根据黄河流域上、中、下游水资源特点和农业生产现状对其节水高效农业的建设途径进行了探讨。建设高效节水的现代灌溉农业和现代旱地农业是黄河流域农业用水战略的必然选择。研究结果和结论对该区域维持21世纪农业可持续发展具有重要意义。     

Technical change in fisheries

Technical change in fisheries is an under-researched area in resource economics and management. This is surprising, because technical progress is the main driver of the development in fishing power and capacity. This article reviews the recent research and development in technology that have occurred in fisheries. New policy implications of introducing technical change into the standard bioeconomic model are illustrated. Bycatch saving technical change is critical to bycatch reduction and ecosystem based fisheries management, and optimal policies cost-effectively reduce bycatch, create incentives to induce bycatch saving technical change, and establish technology policy for research and development.     

建筑围护结构节能与防火体系构建

从围护结构节能与防火一体化思路出发,提倡钢筋混凝土结构保温一体化建筑体系和砌体结构保温一体化建筑体系;尤其主张在我国建筑工业化全面升级的基础上大力开发与推广保温型混凝土预制装配化技术,统一建筑模数,实现标准化与多样化;针对预制装配化保温型混凝土在梁、构造柱等容易出现的冷、热桥问题的部位,创新式提出以相变储能材料与建筑结构相融合来提高建这些部位的热工性能,减少温度梯度;从系统上做到保温与建筑同寿命、免维护、工序少,工期短、耐火等,从而真正实现低碳,构建建筑围护结构节能防火一体化建筑体系。     

Global virtual-land flow and saving through international cereal trade

With intense urbanization and sustained population growth, securing food production with limited land sources has increasingly become a pressing issue. Based on an analysis of international cereal (i.e., barley, buckwheat, maize, oats, rice, rye, sorghum, soybean, and wheat) trade and differences in yields of the cereal between export and import countries over the period of 2007 to 2011, we explore the great potential of land saving through the international cereal trade. By ‘land saving’, we refer to the reduced global total of lands required to produce a necessary amount of cereal when cereal is exported from a country with relatively large yield of the cereal to a country with relatively small yield of the cereal. Our scenario analysis suggests that international cereal trade would help mitigate the shortage of domestic arable land for many island countries (e.g., Japan) and countries in the arid Middle East and North Africa (e.g., Syria and Morocco). Furthermore, international cereal trade has the potential to generate ‘land saving’ of 50,092,284 ha of land per year, which is roughly the size of Spain. Drawing upon the definition of a similar concept — virtual water (Hoekstra and Hung 2002), we define virtual land as the area of land resources used for the production of goods. Through introducing the concept of virtual land, we believe land resources that are traditionally considered as stationary resources can flow with anthropogenic socioeconomic activities. The largest virtual-land flows (> 3,000,000 ha/year) exist between the United States (US) to China, Brazil to China, the US to Japan, the US to Mexico, and Argentina to China. However, not all virtual-land flows necessarily result in land saving. Thus, more endeavors are needed to plan the virtual-land flows for a larger land saving at the global scale.     

地质钻探技术与应用研究

钻探技术是取得地下实物资料、验证地下信息推断与解释、最终圈定矿体、计算储量、评估品位唯一的技术手段,是实现取得宏观影响大成果的重要技术支撑.我国钻探技术和装备水平与国外先进国家相比有很大的差距,但近些年来有了长足的发展.通过国家重大科学工程项目“中国大陆科学钻探工程”5158m“科钻一井”的实施,取得了一系列钻探技术成...     

中国实施铁路电气化的节能减排量估算

基于中国铁路部门逐年统计数据,计算了1975-2007年中国电气化铁路带来的逐年节能量和CO2、烟尘、SO2、CO、NOx与CnHm的直接减排量,并分析了其变化特点.结果表明,33年来电气化铁路使得中国铁路运输行业年均节省123.0万t标准煤的能源消耗,节能量年均增长13.9万t标准煤;CO2、烟尘、SO2、CO、NO...     

气候变暖对刚察县采暖气象指标的影响及节能潜力分析

利用青海省刚察县1961—2008年逐日气温资料,运用数理统计等方法,分析了该地区采暖期气象条件变化及节能潜力。结果表明,1961—2008年间,刚察县采暖期平均气温上升,负积温减少,采暖初日推迟、终日提前,采暖长度明显缩短;采暖度日与采暖期平均气温关系密切,采暖度日呈极显著下降趋势,特别是1994年气温突变后,下降趋势更加明显,冬季寒冷程度有所减弱,能耗需求量减小;该县采暖能源需求异常偏多主要分布在20世纪60年代,偏多年份以70—80年代为主,偏少年份出现在80年代中期以后,主要集中在2000年以后。气候变暖所致采暖节能率为7%,这对节约能源、减少大气污染和温室气体排放较为有利。     

河北临城水资源现状分析及节水对策

临城县属于缺水地区,随着社会经济的发展,需水量急剧增加,供需矛盾日益加剧.水资源可持续利用问题亟待解决.农业是用水大户,为实现水资源的可持续利用,论述农业节水几种途径及生活、工业节水的途径,合理开发利用水资源.     

农业节水灌溉环境影响系统分析

在分析节水灌溉实施区水资源利用现状的基础上, 选择34个因子建立环境指标体系, 用层次分析法(AHP)对节水灌溉项目实施前、后环境影响进行了综合分析与评价。结果表明: 项目实施后, 环境质量总体变化为正值, 有29个环境因子向有利方向发展(P_i>0)。环境变化显著度排序依次是自然生态、社会状况、环境质量、设施建设、农业生态、社会经济。     

中国农村资源,环境与发展的可持续性评估：SEEA方法及其应用

基于一体化核算体系（Ｓｙｓｔｅｍ ｏｆ Ｅｎｖｉｒｏｎｍｅｎｔａｌ－Ｅｃｏｎｏｍｉｃ Ａｃｃｏｕｎｔｉｎｇ简写为ＳＥＥＡ）分析１９９０￣１９９６年间中国农村的资源净产值、环境净产值和真实储蓄。表明中国农村经济发展的资源与环境代价巨大。资源净产值每年损失幅度为２１￣１４２６亿元,平均占农村总产值的１．７２％;环境净产值每年损失幅度为６０４￣１０５９亿元,平均占农村总产值的２．３３％;真实储蓄在－１２