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热带和亚热带地区沿海海洋的相互作用:夏威夷为例
The culture, subsistence, and welfare of tropical and subtropical Pacific Island Nation people are all in some way tied to the interactions between the land and the adjacent and surrounding coastal waters. Land use plays an important role in the relative chemical species distribution and concentrations of particulate and dissolved nutrients that reach coastal waters by riverine, groundwater, and atmosphere. Some key human activities on land that affect coastal waters through land-sea connections and interactions are: (1) the application of nitrogenous and phosphorus-bearing fertilizers and biocides to the landscape and subsequent leaching of significant proportions of these materials into water courses, (2) the release of sewage into aquatic systems, including directly into coastal ocean waters, (3) the diversion of water flows through channelized structures and dams resulting in changes in retention times of water, nutrients and sediments and also in riparian communities on land and hence changes in water, nutrient and suspended sediment fluxes to the coastal ocean, (4) deforestation and/or conversion of land type from, for example, agricultural use to urban housing, (5) the fallout of nitrogen from the atmosphere derived from combustion sources on land and its ultimate transport into aquatic systems, (6) CO2 emissions from fossil fuel and land-use activities (e.g., deforestation) and absorption of some of this CO2 by coastal and open ocean waters, and (7) atmospheric nitrogen emissions from combustion sources on land that ultimately fall directly on the ocean surface, and especially that of the coastal ocean.
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建设环境在运输方面的影响:能源的使用,温室气体的排放,和其他因素
Planning initiatives in many regions and communities aim to reduce transportation energy use, decrease emissions, and achieve related environmental benefits by changing land use. This report reviews and summarizes findings from existing literature on the relationship between the built environment and transportation energy use and greenhouse gas emissions, identifying results trends as well as potential future actions. The indirect influence of federal transportation and housing policies, as well as the direct impact of municipal regulation on land use are examined for their effect on transportation patterns and energy use. Special attention is given to the 'four D' factors of density, diversity, design and accessibility. The report concludes that policy-driven changes to the built environment could reduce transportation energy and GHG emissions from less than 1to as much as 10by 2050, the equivalent of 16-18of present-day urban light-duty-vehicle travel. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency project initiated to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to transportation.
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未来气候变化,海平面上升和海洋酸化对夏威夷和西太平洋渔业管理的影响
The culture, subsistence, and welfare of tropical Pacific Island Nation people are all in some way tied to their proximate fishery resources. Many of these fisheries are already under considerable stress and duress due to human practices such as overfishing, pollution and runoff, habitat destruction and degradation, lack of proper management protocols, and coastal and global population pressures. Other human activities such as fossil fuel use, deforestation and changes in land use and consequent emissions of gases and particulates, such as carbon dioxide, sulfur dioxide, methane, etc., to the atmosphere are contributing to alteration of the global climate by a general overall warming of the planetary atmosphere. The warming of the overlying atmosphere in turn warms the underlying surface ocean. In addition to the surface ocean warming, there is also the problem of ocean acidification owing to absorption of anthropogenic carbon dioxide by the surface waters of the ocean. This input of atmospheric carbon dioxide into the surface ocean reduces the surface water pH, which is detrimental to calcifying organisms such as those that are integral to coral reefs or the planktonic calcareous coccolithophoridae and foraminifera. Climate change and ocean acidification both have the capacity to impact simultaneously all organism trophic levels and so the possible negative ramifications can and should not be underestimated.