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951.
针对环境科学的特点,立足于长远发展,从生态哲学角度分析了生态道德观对环境科学技术的重要价值。分析认为应用生态的观点来学习和研究环境科学,才能达到最大程度防治的目的;合理融入生态观念的环境治理技术有利于经济发展;生态道德观是环境科技工作者必备的品质和环境科学发展的动力。通过这三个方面的分析得出环境科学技术的发展必须以生态道德观为指导的结论。另外本文从纵向和横向分析了生态道德观在指导环境科学技术发展过程中存在的问题并提出了相应的措施和建议。 相似文献
952.
山东省城市生活垃圾管理现状及对策 总被引:2,自引:0,他引:2
随着经济的发展,城市生活垃圾逐渐成为山东省面临的重大问题.系统分析了山东省城市生活垃圾的收运及处理现状,并对其对策进行了讨论,认为山东省应立足现实,完善城市生活垃圾管理体系;对城市生活垃圾分类收集,以源头控制为主,并逐步改进现有的较为单一的卫生填埋技术;尝试应用多种先进的综合处理新技术,改变传统的思维模式,加快城市生活垃圾处理市场化、产业化的步伐,走可持续发展之道路. 相似文献
953.
从湛江旅游资源、经济发展及其区位特点等方面,分析了湛江在创建"全国优秀旅游城市"过程中存在的问题,并提出了解决对策,以期为同类型城市旅游业的发展提供一条新思路. 相似文献
954.
灰白银胶菊的开发利用 总被引:1,自引:0,他引:1
介绍了有关灰白银胶菊的一些生物学特征,探讨了作为天然橡胶资源的市场开发利用价值,以及可能对半干旱区生态环境的影响,并针对开发利用中可能出现的问题提出了建议. 相似文献
955.
基于MAPXTREME的WEBGIS开发浅析--以山东省辖淮河流域水环境WEB管理系统开发为例 总被引:5,自引:0,他引:5
区域水环境信息是空间的重要组成部分,通过将地理信息系统与Internet相结合,以山东省辖淮河流域水环境WEB管理系统的开发过程为例,对当前主流的WEBGIS实现技术及常用开发方法作了较为系统的论述. 相似文献
956.
对ppl空间、wppl空间、metaLindelf空间的映射性质进行了探讨,证明了ppl空间、wppl空间、metaLindelf空间被可数对一开映射保持。 相似文献
957.
T. D. Blackall M. R. Theobald C. Milford K. J. Hargreaves E. Nemitz L. J. Wilson J. Bull P. J. Bacon K. C. Hamer S. Wanless M. A. Sutton 《Water, Air, & Soil Pollution: Focus》2004,4(6):279-285
Ammonia emissions from two contrasting seabird colonies in Scotland were measured, based on the determination of atmospheric concentrations downwind of the colonies. Atmospheric concentrations of ammonia (NH3) across the downwind plume were compared with the inverse application of a Gaussian dispersion model (ID) to calculate the modelled NH3 emission that would generate the measured cross-wind-integrated plume concentration. In parallel, a tracer gas (sulphur hexafluoride, SF6) was released from the colonies with air samples taken to allow determination of SF6 concentrations. On the basis of the known emission rate of SF6, the magnitude of ammonia emissions was estimated by the cross-wind-integrated tracer ratio (TR) of NH3/SF6 concentrations. Coupled with data on annual bird attendance, the measurements indicate annual emissions from the Isle of May and the Bass Rock of 18 and 132 tonnes NH3-N year–1, respectively. The measured NH3 emissions were compared with estimates of seabird nitrogen excretion to estimate the proportion of excreted N that is volatilised as NH3 (FNr). The emission estimates of the two methods compared favourably, giving 4 and 6 kg NH3-N h–1 (FNr = 15%) for the Isle of May for the ID and TR methods, respectively, and 21 and 25 kg NH3-N h–1 (FNr = 50%) for the Bass Rock for the ID and TR methods, respectively. The results provide the first measurement-based estimates to allow regional up scaling of ammonia emissions from seabirds. 相似文献
958.
David Fowler Jennifer B. A. Muller Lucy J. Sheppard 《Water, Air, & Soil Pollution: Focus》2004,4(6):3-8
This paper provides the background to this special issue, outlining the extent to which the global atmospheric nitrogen cycle has been modified by human activity and outlining the range of effects. The global total emissions of reduced and oxidized nitrogen, amount to 124 Tg N, and exceed those from natural sources (34 Tg N) by almost a factor of four showing the extent to which anthropogenic activity has taken over the global N cycle. Of the 124 Tg N, 70 Tg N is emitted in the oxidized form, largely as NO and 70% of which results directly from anthropogenic activity. The remaining 54 Tg N is emitted as NH3, (66% anthropogenic). The enhanced nitrogen emissions are associated with a range of local, regional and global issues including, acidification, eutrophication, climate change, human health and tropospheric O3. The paper also places the Global Nitrogen Enrichment (GaNE) research programme in the UK in a wider perspective. 相似文献
959.
M. R. Theobald U. Dragosits C. J. Place J. U. Smith M. Sozanska L. Brown D. Scholefield A. Del Prado J. Webb P. G. Whitehead A. Angus I. D. Hodge D. Fowler M. A. Sutton 《Water, Air, & Soil Pollution: Focus》2004,4(6):135-142
The distribution and impacts of different nitrogen pollutants are inextricably linked. To understand the problem fully, the interactions between the different pollutants need to be taken into account. This is particularly important when it comes to abatement techniques, since measures to reduce emissions of one nitrogen pollutant can often lead to an increase in another. This project represents a step towards greater understanding of these issues by linking together new and existing nitrogen flux models into a larger framework. The modelling framework has been constructed and some of the nitrogen flows between fields, farms and the atmosphere have been modelled for a UK study area for typical farm management scenarios. 相似文献
960.
Davey L. Jones John F. Farrar Kevin K. Newsham 《Water, Air, & Soil Pollution: Focus》2004,4(6):169-175
Amino acids constitute one of the largest inputs of organic nitrogen (N) to most polar soils and have been hypothesized to be important in regulating vegetational succession and productivity in Arctic ecosystems. Our understanding of amino acid cycling in these soils, however, is poor. The aim of this study was to investigate the size and rate of turnover of the amino acid pool in a range of Arctic and Antarctic soils. Our results indicate that in polar soils with either high or low ornithogenic inputs the amino acid pool is small in comparison to the inorganic N pool (NO–3 and NH+4). The free amino acid pool constituted only a small proportion of the total dissolved organic nitrogen (DON) pool in these soils. Here we show that these low concentrations may be due to rapid use by the soil microbial community in both Arctic and Antarctic soils. The turnover of the amino acid pool in soil was extremely rapid, with a half-life ranging from 2 to 24 h, indicating that this N pool can be turned over many hundred times each summer when polar soils are frequently unfrozen. The implications of amino acids in N cycling and plant and microbial nutrition are discussed. 相似文献