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71.
苏警东 《林业劳动安全》2003,16(1):40-40,42
本文从节增效的角度谈提高沸腾炉的效率,即通过调节风量,风室风压,沸腾温度,提高锅炉热效率,节能增效。  相似文献   
72.
本文从热泵工作原理入手,阐述了可再生能源水源热泵技术替代解决燃煤城市冬季采暖的能源问题,进而为改善大气环境质量,推广应用清洁能源做一有益的尝试。同时也为治理乌鲁木齐市的大气污染及调整能源结构提出了一条新思路。  相似文献   
73.
Maplnfo机助制图在土地利用总体规划中的应用   总被引:2,自引:0,他引:2  
在土地利用总体规划中,传统的模拟制图日益暴露出其局限性。随着信息时代的到来,计算机机助制图以其强大的优势逐步取代了传统的模拟制图。阐述了在土地利用总体规划中应用Maplnfo机助制图的必要性和工作原理,并着重探索其在土地利用总体规划中的应用过程。  相似文献   
74.
This article does not focus on adaptation or mitigation policy directly but on an allied opportunity that exists for the Pacific Islands via the auspices of the Climate Convention, because the existing very costly energy systems used in the Pacific Island region are fossil-fuel dependent. It is argued here that efforts can be made towards the development of energy systems that are ecologically sustainable because Pacific Island nations are eligible to receive assistance to introduce renewable energy technology and pursue energy conservation via implementation mechanisms of the Climate Convention and, in particular, through transfer of technology and via joint implementation. It is contended that assistance in the form of finance, technology, and human resource development from developed countries and international organizations would provide sustainable benefits in improving the local Pacific Island environments. It is also emphasized that mitigation of greenhouse gas emissions is not the responsibility of the Pacific Islands as they contribute very little on a per capita global scale and a tiny proportion of total global greenhouse gas emissions.  相似文献   
75.
This paper develops the idea that the principle of equitable utilization must be applied in concert with sustainable water use not only in the resolution of specific disputes but in the cooperative management of water resources in general. It illustrates this point with two different cases involving the use of the Danube River. The first is the conflict over the Gabcikovo Nagymaros Dam, which now rests before the International Court of Justice. The author argues that a narrow legal ruling that fails to take into account broader issues of equitable utilization as they relate to sustainable development will not satisfactorily address the long-term questions at stake between the parties. The second involves the situation in the Danube Delta where the potential for conflict exists, but may be minimized through the convention and institutional framework developed to address the environmental degradation and pollution of the Danube River basin, which is based in part on the principle of equitable utilization and the goal of achieving more sustainable water use. The paper provides a brief overview of the geographical features of the Danube River and international water law. It then explores the principle of equitable utilization and sustainable water use in light of the two cases and discusses the implications for the resolution and management of conflicts involving internationally shared water courses.  相似文献   
76.
南滚河自然保护区的蕨类植物资源及其特点   总被引:2,自引:1,他引:2  
本文记载了南滚河自然保护区蕨类植物29科47属58种和它们的用途、分布区以及生境因子,并对其地理分布和生态特点进行了分析.  相似文献   
77.
ABSTRACT: Protection of ecosystems as entities on the landscape has attracted a wide range of support. Ecosystem-based public policies are claimed to be more effective, efficient, and scientifically sound than other approaches to environmental and natural resource policy. The ecosystem concept was never intended to serve as a public policy guide or to determine landscape units for land management purposes. This paper critically examines the use of the ecosystem concept in public policy and land use management and analyzes the proposed rule to manage the National Forest System according to ecosystem management principles. The concept is found to be unsuitable as a basis for guiding environmental and natural resource public policies in general while the proposed rule to manage the national forests according to ecosystem management principles is shown to be incoherent.  相似文献   
78.
ABSTRACT: Atrazine and atrazine-residue (atrazine + two metabolites - deethylatrazine and deisopropylatrazine) concentrations were examined to determine if consideration of these atrazine metabolites substantially adds to our understanding of the distribution of this pesticide in groundwater of the midcontinental United States. The mean of atrazine.residue concentrations was 53 percent greater than that of atrazine alone for those observations above the detection limit (> 0.05 μg/l). Furthermore, a censored regression analysis using atrazine-residue concentrations revealed significant factors not identified when only atrazine concentrations were used. Thus, knowledge of concentrations of these atrazine metabolites is required to obtain a true estimation of risk of using these aquifers as sources for drinking water, and such knowledge also provides information that ultimately may be important for future management policies designed to reduce atrazine concentrations in ground water.  相似文献   
79.
九华山风景名胜区是山岳型宗教旅游地。通过对九华山风景区的实地调查,总结了该类旅游地的土地利用特点,即统一性和协调性、难以变更性、总量有限性,并进行了土地利用沿革、变更和影响方面的分析。利用层次分析法从生存指标、发展指标、社会指标、环境指标和智力指标5个方面对九华山风景区的土地利用进行了定量讨论,认为九华山风景区土地利用问题现阶段主要集中在九华街景区、花台景区和柯村景区。在此基础上,对九华山风景区土地的可持续利用提出了相应的对策。  相似文献   
80.
利用淮河流域旱涝易发区的安徽省寿县农田下垫面陆气相互作用观测试验资料,重点分析观测期内CO2通量、能量交换和水汽输送的季节变化,并讨论了与此有关的辐射分量通量、下垫面反射率、波恩比、能量闭合守恒、土壤温度和土壤湿度的季节变化.结果表明CO2通量、能量分配受地表农作物长势影响明显,其中,水稻灌浆、成熟期,被稻田吸收的CO2通量最大可超过2 mg·m-2·s-1,潜热通量达到正的极大值.稻田光合作用最旺盛时期吸收的CO2通量和释放的潜热通量均大于小麦田光合作用最旺盛时期的对应量.较大土壤热通量对应于较低的土壤水含量.试验观测期的下垫面平均反射率为0.14.作物生长期,稻田表面潜热是下垫面吸收能量的主要消费者,小麦田表面潜热和感热相当.能量闭合率ε的变化范围为0.4~1.  相似文献   
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