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111.
中国工业化进程与能源矿产供需均衡的研究 总被引:2,自引:0,他引:2
工业化与能源需求的均衡关系及解决工业化进程中能源供需失衡的战略途径是中国工业化进程中需要探讨的重大问题.文章运用协整技术,就1990-2008年间中国工业化进程与能源需求协整关系的检验,认为中国工业化与能源需求增长具有长期稳定的均衡关系,能源需求将继续保持增长,能源利用效率也将持续提高.然而工业化进程中重工业化高能耗结构特征与能源低效利用并存的困境以及能源供需矛盾不利于能源供需平衡的平稳发展.我国应适应工业化进程的基本规律,转变能源消费方式;走新型工业化道路,适当限制低附加值产业发展,鼓励产业向离附加值、低能耗、高技术产业转移;在实现能源开发利用技术进步和创新的同时.有效利用国内外能源资源;建立能源应急机制等战略途径来实现工业化进程中能源供需平衡发展. 相似文献
112.
循环经济的范式研究 总被引:1,自引:0,他引:1
冯之浚 《中国人口.资源与环境》2007,17(4):10-13
发展循环经济是落实科学发展观、实现经济增长方式根本性转变的重要途径。借鉴“范式”理论探讨和研究了循环经济范式替代末端治理范式的变革:①自然资源的价值得到重估。循环经济范式中将自然资源列为最重要的资源形式。认为它是人类社会最大的资源储备,提高资源生产率是解决环境问题的关键。②不同生态伦理得到整合、提升。循环经济的生态伦理基础强调“生态价值”的全面回归.主张在生产领域和消费领域向生态化转向,承认“生态位”的存在和尊重自然权利。它既包含了现代人类中心主义、生命中心主义和生态中心主义兰种生态伦理追求人类道德完善的合理成分。又补充了各自其不完善的方面o③生态阈值的研究得到深化。循环经济范式的基本前提之一是认为生态阈值是客观存在的。强调在生态阈值的范围内合理利用自然资源.从原来的仅对人力生产率的重视转向在根本上提高资源生产率。在尊重自然的基础上切实有力地保护生态系统的自组织能力。实现经济发展和环境保护的目的。④深层生态学的研究得到加强。循环经济范式是一种深层生态学。符合天人调谐的理念。它不仅强调技术进步.而且将制度、体制、管理、文化等因素通盘考虑,注重观念创新和生产、消费方式的变革.树立了人与自然和谐发展的价值观念。 相似文献
113.
Zhang Jing Feng Zhiming Yang Yanzhao 《中国人口.资源与环境(英文版)》2006,4(2):33-40
The article puts forward the process and means of regional water and land balance research, and then from two scenarios which are the balances under natural regulation and human intervention, calculated and analysed the balance between water and land on Ningxia Plain. For the balance under natural regulation named farmland water balance, using farmland water resource balance equation, the research estimated the monthly farmland" water balance of 8 major crops for all of the 12 counties on Ningxia Plain in the period of 1960-2001; for the balance under human intervention, the research estimated land-use water balance equation of the counties in 2000, and calculated the balance between land use and water resources including irrigating water of all the 12 counties on Ningxia Plain. Results showed that ①precipitation can not meet the water demand of the crops for growth and development on Ningxia Plain, and water shortage is the primary character of farmland water balance under natural regulation. ②the diversity of water and land balance of different counties is distinctly influenced by the crop structure, water quantity for irrigation and irrigation level. ③Irrigation water could meet the crop water demand on Ningxia Plain in 2000, but there was not much space to expand irrigating cultivated land. 相似文献
114.
Humans can consume a number of types of biota tissues, which have varying propensities to accumulate radionuclides. As a result, depending upon the biota species, the radionuclide and the tissue under consideration, it may be necessary to estimate the percent radionuclide load in specific edible tissues, and in cases where whole organisms are consumed, to estimate the radionuclide load in the whole body of an organism, based on data that have been collected for individual tissues. To accomplish this, data were compiled that can be used to estimate the partitioning patterns and percent loads of various groups of elements in edible tissues of freshwater fishes. General trends in partitioning, such as those provided in this paper, can be used to predict radionuclide transfer to humans and the corresponding potential radiological dose to humans via dietary pathways, in this case following the consumption of fish. 相似文献
115.
本文在分析长江三峡工程用地特点的基础上。对大型水利水电工程实施耕地补偿制度中的问题和困难进行调查研究,认为应从新的视角来认识大型水利水电工程的耕地占补平衡问题。进而探索耕地补偿制度实施的新途径和新方式。应在耕地总量动态平衡政策适当调整的基础上.将“以地补地”和“缴费补地”的方式相结合。既通过土地整理.在提商土地质量的前提下增加耕地的有效面积:又要落实耕地开垦费.扶持库区的土地整理。从而使库区的耕地占补制度顺利实施。 相似文献
116.
总量控制是控制污染源发展趋势、改善环境质量、实现经济社会可持续发展的重要途径,如何在适度公平的基础上寻求环境、经济、技术、资源等整体最优是环境科学领域的研究课题。本文以工业城市苏州市为例,研究其工业化学需氧量的排放特征,以基尼系数法分行业对其工业化学需氧量排放量的公平性进行评价,并将总量控制与资源、社会和经济相联系,以行业经济效益最大化和增加治理投资费用最小化为目标,利用多目标行业总量优化分配模型对苏州市的工业化学需氧量排放总量进行优化分配。研究结果表明,纺织业、化学原料及化学制品制造业、能源和水的生产与供应业、造纸及木材加工、医药制造业等行业是苏州市的化学需氧量重点排放行业,经优化分配后,COD排放总量削减了10%,新鲜用水量减少了41.81%,行业年总产值增幅达到214.69%,资源和水环境容量在满足一定的经济增长速度的条件下实现优化配置,总量控制制度在市场经济体制下发挥出尽可能大的环境效益和经济效益。 相似文献
117.
目的研究不同海拔大气压力特别是高空条件对水平对置活塞汽油机热平衡性能的影响。方法利用内燃机高空模拟试验台进行不同海拔高度(0~7000 m)下水平对置活塞汽油机的热平衡试验,测得不同海拔下排温、缸体表面温度等特征参数,计算热流量分配特性,并对比分析热流量分配特性随海拔高度的变化规律。结果随海拔升高,汽油机排温和缸体表面温度逐渐下降,且海拔愈高,缸体表面温度下降幅度愈大。汽油机有效功率随海拔升高逐渐下降,余项损失百分比逐渐上升,且在低转速下,变化幅度增大。在6000 m模拟海拔、3000 r/min转速下,汽油机有效热效率不到5%,而余项损失达到了30%以上,此时部分汽油甚至并未燃烧。结论高空环境对水平对置汽油机热平衡性能造成严重影响,成为制约其高海拔性能恢复的关键因素。 相似文献
118.
Gregory J. McCabe Mark A. Ayers 《Journal of the American Water Resources Association》1989,25(6):1231-1242
ABSTRACT: The Thornthwaite water balance and combinations of temperature and precipitation changes representing climate change were used to estimate changes in seasonal soil-moisture and runoff in the Delaware River basin. Winter warming may cause a greater proportion of precipitation in the northern part of the basin to fall as rain, which may increase winter runoff and decrease spring and summer runoff. Estimates of total annual runoff indicate that a 5 percent increase in precipitation would be needed to counteract runoff decreases resulting from a warming of 2°C; a 15 percent increase for a warming of 4°C. A warming of 2° to 4°C, without precipitation increases, may cause a 9 to 25 percent decrease in runoff. The general circulation model derived changes in annual runoff ranged from ?39 to +9 percent. Results generally agree with those obtained in studies elsewhere. The changes in runoff agree in direction but differ in magnitude. In this humid temperate climate, where precipitation is evenly distributed over the year, decreases in snow accumulation in the northern part of the basin and increases in evapotranspiration throughout the basin could change the timing of runoff and significantly reduce total annual water availability unless precipitation were to increase concurrently. 相似文献
119.
Joie C. Taylor Nick van de Giesen Tammo S. Steenhuis 《Journal of the American Water Resources Association》2006,42(4):1113-1126
ABSTRACT: Water resource management in West Africa is often a complicated process due to inadequate resources, climatic extremes, and insufficient hydrological information. Insufficient data hinder sustainable watershed management practices, one of the top priorities in the Volta River Basin. This research properly fills in missing data by modeling the hydrological distribution in the Volta River Basin. On average, discharge gages across the basin are missing 20 percent of their monthly data over 20 years. Two methods were used to supplement missing data: a statistically linear model and a conceptual hydrological model. A linear equation, developed from the regression of precipitation and runoff, was used to evaluate the quality of existing data. The hydrological model separates the system into root and groundwater zones. Measured values were used to calibrate the hydrological model and to validate the statistical model. The quality of existing data was analyzed and organized for usability. Accuracy of the hydrological model was also evaluated for its effectiveness using R2 and standard error. It was found that the hydrological model was an improvement from the linear model on a monthly basis; R2 values improved by as much as 0.5 and monthly error decreased. Monthly predictions of the hydrological model were used to fill gaps of measured data sets. 相似文献
120.
Cao Junji Lee Shungcheng Zheng Xiangdong Ho Kinfai Zhang Xiaoye Guo Hai Chow Judith C. Wang Hongbin 《Water, Air, & Soil Pollution: Focus》2003,3(2):213-229
In April 1998, two intense dust storms were generated in CentralAsia and transported eastward across East Asia (15 and 19 April). This article presents the chemical characterization ofHong Kong (HK) aerosols during the dust storms. During the 15 Aprildust storm, hourly respiratory suspended particles (RSP)(particle diameter smaller than 10 m) concentrationsmonitored at 7 sites in Hong Kong reached the peak valuessynchronously between 9 and 11 a.m. on 17 April, in which thehighest concentration was 267 g m-3. Analysis ofthe RSP samples showed that concentrations of crustalelements (Ba, Ca, Cd, Cr, Fe, Mg, K+) and anthropogenicspecies (As, Ni, Pb, Zn, NH4
+, NO3
-,SO4
2- and total carbon) were substantiallyenhanced. Enhancement of these species was more than afactor of 2 to 14 relative to the non dust period. The totalcarbon content was high, at 59 g m-3 (notincluding carbonate), and the enrichment factors of Asand Pb on 17 April were 122 and 117, respectively. Thisimplied that anthropogenic materials together with mineraldust were transported to HK from Mainland China. Based onmaterial balance calculations, mineral dust contributed41% to the observed RSP mass on 17 April, which was 2 times thatof the nondust sample (22%). From the 5-day backwardtrajectory analysis, this storm was transported directlyfrom Northwest China to HK. However, there was nocorresponding observation for the 19 April dust stormaerosol. Consequently, 15 April storm had stronger impact onHK's atmosphere than 19 April storm. Compared to the HK AirQuality Objective, 15 April dust storm did not cause seriousair pollution in HK. 相似文献