Climate change, deforestation, and the fate of the Amazon

The forest biome of Amazonia is one of Earth's greatest biological treasures and a major component of the Earth system. This century, it faces the dual threats of deforestation and stress from climate change. Here, we summarize some of the latest findings and thinking on these threats, explore the consequences for the forest ecosystem and its human residents, and outline options for the future of Amazonia. We also discuss the implications of new proposals to finance preservation of Amazonian forests.     

Deforestation and increased flooding of the upper Amazon

The height of the annual flood crest of the Amazon at Iquitos has increased markedly in the last decade. During this same period, there has been greatly increased deforestation in the upper parts of the Amazon watershed in Peru and Ecuador, but no significant changes in regional patterns of precipitation. The change in Amazonian water balance during the last decade appears to be the result of increased runoff due to deforestation. If so, the long-predicted regional climatic and hydrological changes that would be the expected result of Amazonian deforestation may already be beginning.     

亚马逊网络书店的信息检索

文章论述了亚马逊网络书店的特征，从图书信息，检索速度，检索途径，检索的交互性等分析了其特的价值．对我国网络书店和图书馆有一定的启示。     

Rationality,habitus, and agricultural landscapes: Ethnographic case studies in landscape sociology

To explain how agricultural landscapes become social constructions of the natural environment, this essay utilizes Jurgen Habermas's concept of rationality and Pierre Bourdieu's constructs of field and habitus to examine how social relationships shape the way three farmers perceive, alter, and evaluate their land. Intensive interviewing and aerial photographs are used to document the processes through which farmers internalize the primary rationalities of social relationships as a foundation of decision-making regarding water impoundments on their land. One farmer internalizes an instrumental rationality while interacting within relationships with the economic and political system; his landscape changes are meant to improve his ability to extract profit from the land. A second case focuses on a farmer who draws upon familial relationships to provide a substantive counter to the instrumental rationalities of economic relationships; he built a pond to conserve soil. The final case is of a farmer who resists social relationships governed by an instrumental rationality; he built a pond to improve and preserve the beauty of his farm.     

高校校园绿化养护管理影响因子及对策研究

校园绿化是校园文化建设的组成部分,在高校校园建设中发挥着不可替代、独特的功能。绿化养护管理在一定程度上决定着校园绿化水平。通过对部分高校园林绿化养护现状调查研究,发现了影响绿化养护水平的诸多因子并加以分析,针对各因子进一步提出所应采取的相应对策及措施。     

园林植物景观评价研究进展

园林植物不仅有利于提高绿地的生态效益,而且可以创造健康的人居环境。园林植物配置在城市园林绿化建设中的地位日益凸显,植物景观的评价已经成为学者研究的重点。概述了近年来园林植物景观评价的研究成果及国内外的研究现状,分析了层次分析法（AHP）,美景度评价法（SBE）,人体生理心理指标测试法（PPI）,审美评价测量法（BIB-LCJ）和语义分析法（SD）的评价特点及其在园林植物景观评价中的应用。提出了5种评价方法适用的绿地类型,指出园林植物景观评价存在的问题,进一步探讨了园林植物景观评价的前景及价值。     

Extinction debt and windows of conservation opportunity in the Brazilian Amazon

Predicting when future species extinctions will occur is necessary for directing conservation investments but has proved difficult. We developed a new method for predicting extinctions over time, accounting for the timing and magnitude of habitat loss. We applied this to the Brazilian Amazon, predicting that local extinctions of forest-dependent vertebrate species have thus far been minimal (1% of species by 2008), with more than 80% of extinctions expected to be incurred from historical habitat loss still to come. Realistic deforestation scenarios suggest that local regions will lose an average of nine vertebrate species and have a further 16 committed to extinction by 2050. There is a window of opportunity to dilute the legacy of historical deforestation by concentrating conservation efforts in areas with greatest debt.     

The future of seawater desalination: energy, technology, and the environment

In recent years, numerous large-scale seawater desalination plants have been built in water-stressed countries to augment available water resources, and construction of new desalination plants is expected to increase in the near future. Despite major advancements in desalination technologies, seawater desalination is still more energy intensive compared to conventional technologies for the treatment of fresh water. There are also concerns about the potential environmental impacts of large-scale seawater desalination plants. Here, we review the possible reductions in energy demand by state-of-the-art seawater desalination technologies, the potential role of advanced materials and innovative technologies in improving performance, and the sustainability of desalination as a technological solution to global water shortages.     

Detection of anthropogenic climate change in the world's oceans

Large-scale increases in the heat content of the world's oceans have been observed to occur over the last 45 years. The horizontal and temporal character of these changes has been closely replicated by the state-of-the-art Parallel Climate Model (PCM) forced by observed and estimated anthropogenic gases. Application of optimal detection methodology shows that the model-produced signals are indistinguishable from the observations at the 0.05 confidence level. Further, the chances of either the anthropogenic or observed signals being produced by the PCM as a result of natural, internal forcing alone are less than 5%. This suggests that the observed ocean heat-content changes are consistent with those expected from anthropogenic forcing, which broadens the basis for claims that an anthropogenic signal has been detected in the global climate system. Additionally, the requirement that modeled ocean heat uptakes match observations puts a strong, new constraint on anthropogenically forced climate models. It is unknown if the current generation of climate models, other than the PCM, meet this constraint.