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41.
云南澜沧江流域热区资源开发及热作基地建设研究   总被引:1,自引:0,他引:1  
李凤钊  彭永岸 《热带地理》1994,14(3):210-217
本文通过对澜沧江流域热区资源的分析,认为该区种植热带橡胶、香料、咖啡、南药、热果、发展甘蔗、茶叶、建立各种热作基地是开发利用热区资源的主要途径;热作布局应在立体布局和地域布局基础上形成大分散、小集中的专业化布局;热区开发应采取相应的措施和特殊政策。  相似文献   
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Non-linear response of the soil is investigated by comparing the spectral ratios (uphole/downhole) using weak and strong motions. Data from seven vertical arrays in Japan are analysed in this study. The frequency-dependent transfer function of soil is calculated as a ratio of the spectrum at uphole to the spectrum at downhole, considering the horizontal component of shear wave. In spectral ratio analysis auto- and cross-spectra are employed. The reduction in the predominant frequency of the transfer function with increases in excitation level reflects the non-linear response of the soil. Results of analysis demonstrate a significant non-linear ground response at six sites with surface PGA exceeding 90 gal. However, the results of one site show the linear response up to 130 gal surface PGA. Furthermore, the in situ strain-dependent soil behaviour is examined through the shear modulus – shear strain relationship. When compared, the actual and laboratory results of the shear strain – shear modulus relationship are in agreement. Additionally, a good consistency between the tendency of reduction in shear modulus ratio with shear strain increases, and reduction of predominant frequency with ground motion increases, confirms the significance of non-linearity in site effects study.  相似文献   
44.
辽中地区矿业城市生态系统脆弱性研究   总被引:10,自引:0,他引:10  
辽中地区矿业城市是中国重要的能源生产和重工业基地,研究其生态系统脆弱性有助于改善该区域环境恶化、生态系统失调的状况,为其可持续发展提供决策依据。基于矿业城市复合生态系统内涵,建立了辽中地区矿业脆弱性评价指标体系,提出生态系统协调度,并设定了其脆弱性和协调性分级标准。结果表明:2005年,辽中地区矿业城市生态系统脆弱性处于亚稳定状态,主要限制因子为资源匹配指数、环境质量指数和经济发展指数;辽中地区矿业城市生态系统间处于亚协调状态,其中本溪略低于亚协调,处于低度失调状态。鞍山的资源匹配指数处于较失调状态,抚顺、本溪的资源匹配指数处于失调状态,抚顺、本溪的经济发展指数处于较失调状态,是限制整个生态系统协调发展的主要原因。该评价模型较真实的反映了辽中地区矿业城市生态系统脆弱性、协调性状况,并且提出了制约其发展主要限制因子。  相似文献   
45.
In recent ten years, Differential Interferometric Synthetic Aperture Radar (D-InSAR) has become a major technique of space-based geodesy together with GPS, VLBI and SLR. Interferometric Synthetic Aper-ture Radar (InSAR) has many advantages, such as all-weather, all-time, strong stability and dynamic survey property, and no requirements for ground sta-tions. In particular, the surveying results by InSAR can cover a large range of the ground deformation field in succession and has gr…  相似文献   
46.
Mesozoic and Cenozoic volcanic rocks are widely distributed in the circum-Pacific area of eastern China. These rocks have long been genetically linked to westward subduction of the paleo-Pacific oceanic plate to the eastern Asia continent[1,2]. Research in re-cent years[3―6] has attained conclusions that a simple paleo-Pacific subduction model does not work well in interpreting all the volcanic rocks in eastern China, although some of them could be attributed to circum-Pacific interaction …  相似文献   
47.
罗承平  薛纪渝 《热带地理》1996,16(3):191-195
本文分析了大气中CO2浓度增加的事实,原因及其发展趋势,结果认为,大气中CO2浓度上升对我国农业的发展产生了一定的不利影响。因此,为控制大气中CO2的上升,必须采取相应的有效对策。  相似文献   
48.
Non-avian theropods are well represented in the Cretaceous of Asia. However, the first theropod remains ever reported from China, from the Wangshi Group of Shandong Province, have not been reassessed since they were described by Carl Wiman in 1929, despite the great strides that have been made in theropod phylogenetics in the last eight decades. The remains redescribed herein consist of four vertebrae (two cervicals, one dorsal and one caudal) from one site, and a caudal vertebra and ungual phalanx from another. The vertebrae from the first site are assigned to tyrannosauroids and ornithomimosaurs, as is the caudal vertebra from the second site, whereas the manual ungual also bears resemblances to those of non-maniraptoran coelurosaurs (specifically compsognathids and ornithomimosaurs). Theropods remain relatively rare in the Wangshi Group; nevertheless, the remains redescribed herein highlight the potential for the discovery of more theropod remains in future excavations.  相似文献   
49.
中西部地区承接产业转移的影响因素研究   总被引:1,自引:0,他引:1  
将中西部地区划分为东北、中部、西北、西南4个区域,采用1995—2013年的相关数据,分析各区域在承接东部发达地区产业转移过程中的主要影响因素。选取的影响因素包括资本存量、经济规模、劳动力成本、人力资源和路径效应。结果发现:4个区域的路径效应、资本存量与产业转移承接地均存在显著正相关关系;人力资源与产业转移承接地存在正相关关系,但东北、西北地区不显著;劳动力成本与产业转移承接地存在负相关关系,但对东北地区不显著;除中部地区外,经济规模与产业转移承接地并不存在显著相关关系。中西部区域地方政府和企业家在促进产业转移进程中应充分发挥比较优势,根据不同影响要素制定宏观政策与微观引资策略。  相似文献   
50.
The question of whether China is on the verge of a ‘shale gas revolution’ is examined. This has potentially significant consequences for energy policy and climate change mitigation. Contrary to the optimistic reading of some commentators, it argues that various technological, environmental, political, regulatory and institutional factors will constrain the growth of China's shale gas market and that such a revolution might in any event have consequences that are at best mixed, at worst antithetical to climate change mitigation.Policy relevanceChina's reserves of unconventional gas have the potential to transform energy policy, as has occurred in the US, resulting in the substitution of shale gas for coal in the energy mix. Because gas emits only approximately half the GHG per unit as coal, such a move would have important implications for climate policy. However, substantial obstacles stand in the way of the ‘energy revolution’ that some policy analysts see China as embarking upon. The need to acknowledge these obstacles, particularly those relating to regulation and governance (and whether or to what extent they can be overcome), is an issue of profound importance to the future of climate and energy policy.  相似文献   
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