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531.
发展生态农业是改善农业生态环境、实现农业可持续发展的有效途径。本文根据河北省农业和农村经济的发展水平、农业资源以及环境状况,提出了一些适宜河北省发展的生态农业模式。  相似文献   
532.
温室效应与气候变暖是深刻影响人类社会发展、人类生存而亟待解决的首要环境问题。在广泛调研的的基础上,从生态可持续发展角度对其进行了阐述。介绍了生态可持续发展理论、环境污染问题的严重性与全球性、近30年的地球异常气候而产生的各种恶性自然灾害、温室效应的产生和发展趋势及温室效应的防治对策。指出温室效应的防治要以生态可持续发展为着眼点,开发利用无污染能源,保护森林、增加植被,研究温室气体回收技术及不产生温室效应的原材料。  相似文献   
533.
厌氧反应器技术研究开发情况简介   总被引:2,自引:0,他引:2  
本文分析了厌氧反应器技术的发展过程,着重介绍了几种新型第三代厌氧反应器技术的原理和应用现状,以及我国目前对这些技术的研究开展情况,其中:升流式厌氧污泥床过滤器(UBF)研究取得了一定的成功经验;垂直折流厌氧污泥床反应器(VBASBR)缺乏应用生产实例;厌氧折流反应器(ABR)已有成功经验;内循环反应器(IC)还只限于部分废水的处理;膨胀颗粒污泥床反应器(ECSB)尚未有规模的生产投入使用。  相似文献   
534.
根据多年来从事井下无轨辅助车辆研究工作的实践和收集到的有关资料,论述了近年来冶金矿山井下无轨辅助车辆的国内外概况及其发展趋势。  相似文献   
535.
本文系统阐述了绿色GDP理论,介绍了我国西部地区的生态环境现状,结合我国西部大开发战略的实施,论述了在西部大开发中,应用绿色GDP来衡量其发展的重要性。  相似文献   
536.
We examined the behavioral and developmental responses of Xenopus laevis larvae to their mirror images in three experiments. The mirrors allowed us to visually simulate increased density, without the tadpoles’ behavior being confounded by chemical cues from additional tadpoles. In the first experiment, we demonstrated that Xenopus tadpoles have a right eye preference for mirrors, contrary to the left eye preference of all other anuran species studied to date. This lateralized eye use disappeared, however, as tadpoles approached metamorphosis. Next, we examined how mirrored aquaria walls affected tadpole growth and development. We found that tadpoles raised in aquaria with partially mirrored walls showed depressed growth compared to tadpoles raised without mirrors, despite the fact that Xenopus larvae normally thrive when raised in visual contact with conspecifics. The tadpoles raised with mirrors had, though not significantly, proportionally larger bodies relative to their tail length (d = 0.51). This suggests that a phenotypically plastic response in body proportions was induced in these tadpoles solely by the sight of other tadpoles. The third experiment established that X. laevis tadpoles are more active in front of a mirror; i.e., they turn more often and spend more time in front of mirrored surfaces. We consider this increased activity to be an aberrant behavior of the tadpoles, which were attempting to school with their own images. We suggest that this extra activity reduced the amount of energy available for growth, accounting for the depressed growth seen in our second experiment.  相似文献   
537.
Sustainable development is a process that has social, cultural, economic and ecological dimensions. The necessity of improving the quality of life of rural women in terms of socio-economic aspects in developing countries like Nigeria is the aim of this study. The study was carried out in four villages of Tonkere district (Okeake, Abagboro, Elefon and Akiri), situated on expansive university land at Ile-Ife and typical of rural settings in Nigeria. Data were generated from group meetings, local government and individual interviews and surveys. In rural Nigeria, women’s essential contributions to overall environmental health, development and economy are negatively influenced by domestic tasks such as gathering of fuel woods and biomass for cooking. In reality, wood burning, kerosene stoves, and open fireplaces emit significant quantities of known health-damaging pollutants. The significant emissions of health-damaging pollutants per unit activity, combined with daily use in close proximity to rural human populations mean household biomass fuel use exposes total population to important pollutants resulting in ill-health and premature dead. Application of solar energy collectors and hosts of solar devices is an alternative energy sources in rural areas that could best improve women’s health, socially and economically, and positively add to ecological dimensions. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
538.
我国桐油发展战略与对策   总被引:6,自引:0,他引:6  
桐油是我国的特产资源,其价值之高,用途之广,早已引起许多国家的重视;其化学结构之特殊,化学性质之活泼,引起许多化学工作者的兴趣,而致力于桐油化学科学的研究。我国种植油桐历史修久,远在公元前六世纪有文记载。新中国成立后,党 和政府非常重视,周总理曾亲自主持全国油桐工作会议,油桐得到了空前发展。  相似文献   
539.
Biodiversity is under threat from anthropogenic pressures, in particular in biodiversity-rich developing countries. Development cooperation actors, who traditionally focus on the improvement of socio-economic conditions in the South, are increasingly acknowledging the linkages between poverty and biodiversity, e.g. by referring to the ecosystem services framework. However, there are many different framings which stress the need for biodiversity integration and which influence how biodiversity and development are and/or should be linked. Moreover, there is a gap between the lip service paid to biodiversity integration and the reality of development cooperation interventions. This study analyses how biodiversity framings are reflected in environmental impact assessment (EIA) practice, and how these framings influence EIA and decision-making. The findings, based on an in-depth qualitative analysis of World Bank EIAs undertaken in West Africa, indicate the incoherent quality but also the dominance of the ‘utilitarian’ and ‘corrective’ framings, which respectively stress human use of nature and mitigation of negative unintended development impacts. Identifying and highlighting these discursive trends leads to increased awareness of the importance of biodiversity among all development actors in North and South. However, some framings may lead to an overly narrow human-centred approach which downplays the intrinsic value of biodiversity. This study proposes recommendations for an improved integration of biodiversity in development cooperation, including the need for more systematic baseline studies in EIAs.  相似文献   
540.
环境规划中植物的景观功能及其应用   总被引:11,自引:0,他引:11  
本文在探讨植物的景观特点及其建造功能和观赏功能等基础上,提出了环境规划中景观规划的基本原则。结合岳阳市南湖旅游度假区的实际情况,应用景观规划的基本原则,研究了该旅游度假区的面上绿化规划和景区景点绿化规划。  相似文献   
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