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71.
72.
Changes in global gravitational energy induced by earthquakes 总被引:1,自引:0,他引:1
Benjamin Fong Chao Richard S. Gross Da-Nan Dong 《Geophysical Journal International》1995,122(3):784-789
73.
我国城市扩张、粮食保障和能源转型形势严峻,如何挖掘城市建成环境的绿色生产潜力、探索一条通过粮食生产和太阳能利用节约土地空间并缓解生态压力的新途径?本文不同于以往生态补偿研究大多以重点生态功能区为对象或以财税补偿机制为手段,而是创新性地建立了一种城市空间内部的生态补偿机制。本文提出城市“绿色生产性面积”作为一种从城市生态学角度来衡量城市生态承载力提升潜力的方法,它基于将城市绿色资源收入换算成相同条件下它们所能节约的生态足迹面积。首先,通过类型学方法建立绿色生产补偿策略;其次,进行城市建成环境的全要素空间清查及其绿色生产潜力分析;最后,建立不同绿色生产的生态节地效益统一核算标准,并转换为绿色生产性土地面积指标。以天津市南开区学府街道为例,通过可利用的屋顶及闲置用地进行绿色生产,补充了该区12%的建筑所占用的自然土地所能提供的生态承载力。 相似文献
74.
帕隆藏布河流纵剖面演化的最小功模式 总被引:3,自引:0,他引:3
河流地貌最小功原理表明河流纵误时面形态将向力示使流速增大的方向演化,据此推导出矩形流域全程流速的平均值(u^-)与河流纵误时面形态指数(N)的关系式:u^∝-f(N)={1/2-1/[(N 1)(N 2)]}^1/2,f(N)被称为流速函数。这一最小功模式表明河流纵剖面演化方向是N由小变大。以西藏帕隆藏布中上游流域系统、干流全程及Ⅰ级阶地为例,由最小功模式计算的全程流速均值与实测值相吻合,从而检验了上述最小功原理和数学模式。 相似文献
75.
76.
MARTIN J. PASQUALETTI 《Geographical review》2000,90(3):381-394
ABSTRACT. Most of us have not known—or cared—where our electricity comes from. Our attitude is changing, however, as we turn toward wind energy, now the fastest‐growing renewable energy resource in the world. Because we cannot extract and transport the raw energy of the wind, reaping its many environmental benefits requires that we cope with the landscape presence of its development wherever it occurs. Sometimes this interferes with the value of open space, and sometimes it may be close to subdivisions. It is the immobility and very visibility of wind power that makes its presence unavoidable. In that regard it cannot be hidden underground, stored in tanks, or moved by trains. It is an energy resource that reminds us that our electricity comes from somewhere. The more we wish to tap the power of the wind, the less we will be able to avoid the responsibilities that our demand for energy brings. This necessary bargain, first evident near Palm Springs, California, is now being experienced wherever wind power is being developed. 相似文献
77.
Surface energy and water vapor fluxes observed in a desert plantation in central Iran 总被引:1,自引:0,他引:1
A. Oliphant P. Zawar-rezaG. Azizi A. DehghanpourJ. Harrison 《Journal of Arid Environments》2011,75(10):926-935
Summertime observations of surface radiation budget, energy balance and atmospheric surface layer meteorology were made on an arid valley floor planted with Haloxylon aphyllum to combat desertification in central Iran. The surface microclimate is characterized and compared with other arid regions and the role of ‘desert greening’ on surface fluxes is considered. A high surface albedo (0.265) and large longwave radiation loss produced relatively low net radiation. Energy partitioning was dominated by sensible and ground heat fluxes with opposing diurnal asymmetry governed by strong diurnal variability in eddy diffusivity. The Bowen ratio was 2.53, which fell inside the range of other vegetated arid surfaces. Surface temperature gradients were strong both in the atmospheric surface layer and in the substrate, with consistent lapse conditions by day and inversions at night. The wind regime included a moderate daytime regional wind which displayed Coriolis turning and weaker nocturnal slope flows. Actual evapotranspiration (1 mm dy−1) was only a small fraction of potential evapotranspiration. The diurnal pattern of AET indicates strong stomatal control. The desert greening effect of Haloxylon plantations provided atmospheric water and reduced sensible heat flux by up to 40%. 相似文献
78.
SOCIAL BARRIERS TO RENEWABLE ENERGY LANDSCAPES* 总被引:2,自引:0,他引:2
MARTIN J. PASQUALETTI 《Geographical review》2011,101(2):201-223
After many years of slow progress, we find that worldwide environmental, political, and economic pressures are providing greater purchase for the accelerated development of renewable energy. Although many people would consider this quickening pace good news, the transition from conventional resources has encountered public resistance. In this article I examine the nature of challenges to the development of geothermal, wind, and solar energy projects in three places: the United States, Scotland, and Mexico. The common thread in the public reservations about renewable energy is landscape change and the consequent disruption such change produces to established ways of life for those who are nearby. It also suggests the importance of rebalancing the emphasis of renewable energy programs away from the traditional technical focus that dominates development planning. The more suitable and expedient approach would be to consider the challenges of development as predominantly social matters with technical components, rather than the other way around. To accept this view is to unlock the door to a renewable energy future. 相似文献
79.
80.
W. Earl Bardsley 《Natural Resources Research》2008,17(4):197-204
A sustainable global silicon energy economy is proposed as a potential alternative to the hydrogen economy. This first visualization
of a silicon energy economy is based on large-scale and carbon-neutral metallic silicon production from major smelters in
North Africa and elsewhere, supplied by desert silica sand and electricity from extensive solar generating systems. The resulting
“fuel silicon” is shipped around the world to emission-free silicon power stations for either immediate electricity generation
or stockpiling. The high energy density of silicon and its stable storage make it an ideal material for maintaining national
economic functioning through security of base load power supply from a renewable source. This contrasts with the present situation
of fossil fuel usage with its associated global warming and geopolitical supply uncertainties. Critical technological requirements
for the silicon economy are carbon-neutral silicon production and the development of efficient silicon-fired power stations
capable of high-temperature rapid oxidation of fuel silicon. A call is made for the development of research effort into these
specific engineering issues, and also with respect to large-scale economical solar power generation. 相似文献