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81.
82.
重庆临峰山森林公园生态系统属于次生林系统,系统的抗害能力较弱。森林公园规划、开发和运营中存在着较为严峻的生态风险。为了保护森林资源,促进森林公园的可持续发展,分析、评价了其主要生态风险源——森林火灾和生态入侵及其危害,并提出了相应的防止对策。 相似文献
83.
我国煤矿矸石的堆放长期以来主要是以露天堆放为主,当遇到雨季,受雨水冲刷产生的废水对环境造成二次污染,香根草是近年来逐渐被重视的生物防治技术,利用香根草良好的固土护坡特性,解决矸石堆放的二次污染问题,取得较好的效果。 相似文献
84.
受山区起伏地形和不均匀下垫面的强烈影响,低层大气在水平和垂直两个方向上形成特殊的风场和温度场,污染物的输送和扩散规律比平原复杂的多.探索山区大气扩散规律是一项重要的研究课题,也是空气环境影响中急待解决的一个问题.本文通过对山区大气扩散特点的研究,在平坦地形大气扩散规律高斯模式的基础上,提出了较典型情况下的地形大气扩散修正公式,并通过模拟计算结果的比较,得出了公式的预测效果. 相似文献
85.
通过对六种植物配置方式及三种开发模式的对比试验分析,试验出了一种融水土保持效益与经济效益于一体的高效生态经济型造林模式,并探讨了灰毡毛忍冬产量与海拔高度的关系.结果表明:在自然条件恶劣的小沙江高海拔山区,采用金银花(品种为灰毡毛忍冬) 三木药材或其它草本药材,运用景观生态学原理进行设计开发,可获得很好的经济效益与社会效益,并能保持山区的可持续发展.同时还试验出了主栽树种灰毡毛忍冬在海拔1000~1400m之间时经济效益最好. 相似文献
86.
本文分析了山区贫困的一般原因。讨论了山区有效资源不足和“单向流失”现象与山区贫困化的关系,并列举了山区工作中的历史失误。本文总结了一些地区采用“长短结合、以短养长”的发展战略,开发优势资源所取得的成功经验,并提出了区域经济、社会、生态协同发展的目标。 相似文献
87.
春季沙尘过程对华东高山背景区域颗粒物中水溶性无机离子的影响 总被引:1,自引:0,他引:1
于2014年3—5月在国家大气背景监测福建武夷山站采集了PM2.5及PM2.5~10样品,利用离子色谱对其中的水溶性组分进行分析,并同步收集气象因子及污染物质量浓度数据,结合后向气流轨迹,分离出受沙尘影响的样品,探讨了春季沙尘过程华东高山背景区域颗粒物中水溶性组分的特征.结果表明,春季武夷山背景点沙尘影响期间颗粒物质量浓度及各水溶性离子浓度均比非沙尘期高,在粗粒子中表现更为明显;沙尘期间NO-3在粗粒子中明显富集,NO-3浓度显著升高;受沙尘影响,粗粒子中阳离子与阴离子的当量浓度比及NO2的二次转化率均明显升高. 相似文献
88.
Soil and water conservation (SWC) contests among farmer groups were organized in five rural villages in the Bolivian mountain
valleys. The contests were aimed at quickly achieving widespread sustainable results. This article analyzes the effectiveness
of these contests as an extension tool. Mixed results were obtained. In three villages, participation rates in the SWC activities
introduced in the contests were still high even 2 years after project withdrawal. These were all villages where a solid foundation
for sustainable development had been laid before the contests were held. Two years later, most families were still involved
in maintenance of the SWC practices introduced in the contests, and many farmers had started to experiment with different
soil management practices. However, replications of these SWC practices were not widespread, Conservation Leaders did not
continue with their training activities, and the quality of maintenance of the practices was often not satisfactory. In order
to become a more effective extension tool and achieve widespread impact, SWC contests must receive continued support by a
catalyst agency. Moreover, other SWC contests should also be organized in which practices are not predefined. Given that SWC
contests are a low-budget extension tool, local municipalities could become more actively involved. 相似文献
89.
C. A. Kessler 《Environment, Development and Sustainability》2008,10(2):233-247
In Bolivia, recent decentralisation policies have broadened the participation of local actors in development processes. However,
development is far from sustainable, and poverty and natural resources degradation still increase. The challenge is to develop
strategies that achieve the genuine participation of poor farmers in natural resources management and sustainable development.
The logical strategy, which was developed and validated in five Bolivian mountain villages, is an example. In this strategy,
first a solid foundation for sustainable development is laid, with activities focussing on five basic conditions for sustainable
development in rural villages: leadership and organisation, responsible participation, effective collaboration, mutual trust
and environmental awareness. The results show that the existence of a solid foundation is crucial for the success of other
development activities, such as soil and water conservation activities. However, given that 2 years after the project’s withdrawal
the firmness of the foundation had slightly weakened, it was concluded that a better integration of these villages in local
development processes is essential to profit from the new dynamics. This is especially true for soil and water conservation.
To achieve this integration, municipalities—with the support of international development agencies—must be encouraged to invest
in laying this solid foundation in rural villages and in facilitating follow-up activities to keep the dynamic process going.
This study shows that such investments result in better organised villages, more equality, and the genuine participation of
more people in sustainable village development. Effective collaboration and accountability at institutional level are, however,
required. 相似文献
90.
Kenneth E. Bencala Ronald E. Rathbun Alan P. Jackman Vance C. Kennedy Gary W. Zellweger Ronald J. Avanzino 《Journal of the American Water Resources Association》1983,19(6):943-950
ABSTRACT: A significant fraction of rhodamine WT dye was lost during a short term multitracer injection experiment in a mountain stream environment. The conservative anion chloride and the sorbing cation lithium were concurrently injected. In-stream rhodamine WT concentrations were as low as 45 percent of that expected, based on chloride data. Concentration data were available from shallow‘wells’dug near the stream course and from a seep of suspected return flow. Both rhodamine WT dye and lithium were nonconservative with respect to the conservative chloride, with rhodamine WT dye closely following the behavior of the sorbing lithium. Nonsorption and sorption mechanisms for rhodamine WT loss in a mountain stream were evaluated in laboratory experiments. Experiments evaluating nonsorption losses indicated minimal losses by such mechanisms. Laboratory experiments using sand and gravel size streambed sediments show an appreciable capacity for rhodamine WT sorption. The detection of tracers in the shallow wells and seep indicates interaction between the stream and the flow in the surrounding subsurface, intergravel water, system. The injected tracers had ample opportunity for intimate contact with materials shown in the laboratory experiments to be potentially sorptive. It is suggested that in the study stream system, interaction with streambed gravel was a significant mechanism for the attenuation of rhodamine WT dye (relative to chloride). 相似文献