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711.
Xie Genzong Qiu Penghua Tang Shaoxia 《中国人口.资源与环境(英文版)》2007,5(1):74-83
As the protected areas of land and coastal environment, nature reserves are designed to address how to reconcile the conservation of biodiversity, the quest for economic and social development and the maintenance of cultural values. This paper establishes a framework for nature reserve development that seeks to incorporate ecotourism into its strategies. The overall purpose was to identify the information needs required for a comprehensive nature reserve that incorporates ecotourism related values. It also illustrates the utility of this framework in the context of the Wuzhishan Mountain Region of China. A literature review, the first phase of a visionary strategy and a subsequent gap analysis for available management information were undertaken in order to achieve this paper's purpose. Finally, recommendations axe pre-sented for integrating ecotourism into nature reserve development in the Wuzhishan Mountain Region. 相似文献
712.
713.
S. Hellsten U. Dragosits C. J. Place T. H. Misselbrook Y. S. Tang M. A. Sutton 《Water, Air, & Soil Pollution: Focus》2007,7(1-3):3-13
Most ammonia (NH3) emission inventories have been calculated on an annual basis and do not take into account the seasonal variability of emissions
that occur as a consequence of climate and agricultural practices that change throughout the year. When used as input to atmospheric
transport models to simulate concentration fields, these models therefore fail to capture seasonal variations in ammonia concentration
and dry and wet deposition. In this study, seasonal NH3 emissions from agriculture were modelled on a monthly basis for the year 2000, by incorporating temporal aspects of farming
practice. These monthly emissions were then spatially distributed using the AENEID model (Atmospheric Emissions for National
Environmental Impacts Determination). The monthly model took the temporal variation in the magnitude of the ammonia emissions,
as well as the fine scale (1-km) spatial variation of those temporal changes into account to provide improved outputs at 5-km
resolution. The resulting NH3 emission maps showed a strong seasonal emission pattern, with the highest emissions during springtime (March and April) and
the lowest emissions during summer (May to July). This emission pattern was mainly influenced by whether cattle were outside
grazing or housed and by the application of manures and fertilizers to the land. When the modelled emissions were compared
with measured NH3 concentrations, the comparison suggested that the modelled emission trend corresponds fairly well with the seasonal trend
in the measurements. The remaining discrepancies point to the need to develop functional parametrisations of the interactions
with climatic seasonal variation. 相似文献
714.
715.
Ian D. Leith Lucy J. Sheppard David Fowler J. Neil Cape Matt Jones Alan Crossley Ken J. Hargreaves Y. Sim Tang Mark Theobald Mark R. Sutton 《Water, Air, & Soil Pollution: Focus》2004,4(6):207-218
Providing an accurate estimate of the dry component of N deposition to low N background, semi-natural habitats, such as bogs and upland moors dominated by Calluna vulgaris is difficult, but essential to relate nitrogen deposition to effects in these communities. To quantify the effects of NH3 inputs to moorland vegetation growing on a bog at a field scale, a field release NH3 fumigation system was established at Whim Moss (Scottish Borders) in 2002. Gaseous NH3 from a line source was released along of a 60 m transect, when meteorological conditions (wind speed >2.5 m s–1 and wind direction in the sector 180–215°) were met, thereby providing a profile of decreasing NH3 concentration with distance from the source. In a complementary study, using a NH3 flux chamber system, the relationships between NH3 concentrations and cuticular resistances were quantified for a range of NH3 concentrations and micrometeorological conditions for moorland vegetation. Cuticular resistances increased with NH3 concentration from 11 s m–1 at 3.0 g m–3 to 30 s m–1 at 30 g m–3. The NH3 concentration data and the concentration-dependent canopy resistance are used to calculate NH3 deposition taking into account leaf surface wetness. The implications of using an NH3 concentration-dependent cuticular resistance and the importance for refining critical loads are discussed. 相似文献
716.
717.
718.
间苯二甲酸二甲酯磺酸钠生产废水的综合利用 总被引:1,自引:0,他引:1
介绍了用溶剂析出法分离间苯二甲酸二甲酯磺酸钠生产废水中硫酸钠和间苯二甲酸二甲酯磺酸钠的新工艺。采用该工艺可回收废水中90%的硫酸钠和80%的间苯二甲酸二甲酯磺酸钠,经济效益显著。 相似文献
719.
为了实现油(气)田(特别是环境敏感地区)开发的可持续发展,在原有基础上,针对水网地区油田开发环境的特点,就现在环境保护技术工作中存在的重点难点问题进行进一步的研究和探讨,完善和发展了整套污染防治工艺、处理技术及处理装备。 相似文献
720.
土体的导热系数是能源岩土工程设计与研究中重要的热物理参数。工程中土体常处于非饱和状态。非饱和土体的导热系数会影响地下结构物的力学性能、热交换效率以及整个热工结构的工作效率。为给能源岩土工程设计与研究提供可靠的热物理参数,通过室内单元试验测量了不同含水率和温度下砾砂、粉土和黏土的导热系数,研究这三种非饱和土体的导热系数与含水率、基质吸力和温度的关系。研究结果表明,三种非饱和土体的导热系数都随含水率的增加而增加,最后趋于稳定。砾砂导热系数增加的速率最快,粉土次之,黏土最小。相同含水率下,砾砂导热系数最大,粉土次之,黏土最小。粉土的导热系数与基质吸力密切相关,其关系曲线趋势近似土 水特征曲线。三种土体的导热系数均随温度的增加近似线性增加,但增加幅度仅为10-3级别,可忽略其影响。 相似文献