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901.
The necessity of incorporating societal and environmental concerns into publicly funded agricultural initiatives in research, extension, and practice is increasingly evident. Agriculturalists are urged to acknowledge and respond to societal concerns before an insensitive and largely ill-informed urban majority assumes a dominant posture in agricultural policy. In recent history, the availability of unrealistically cheap energy encouraged the evolution of a form of commercial agriculture unfettered by sound ecological principles. At present, external, resource-intensive intervention of increasing magnitude is needed to compensate for the apparent ecological instability generated by practices such as intensive cereal management or conservation tillage practices. Polarization of the enterprises of plant and animal agriculture to enable centralized, concentrate-intensive, confinement feeding has disrupted the natural cycling of nutrients and carbon in the soil, encouraged the withdrawal of perennial forages from crop rotations, and invoked a widely ramifying network of agricultural and societal problems. Solutions to these problems must evolve from a holistic and far-reaching appraisal of causes, rather than from a piecemeal approach to individual symptoms. 相似文献
902.
Oettlé N Arendse A Koelle B Van der Poll A 《Environmental monitoring and assessment》2004,99(1-3):115-125
Community knowledge exchanges have played a key role in developmental processes in the Suid Bokkeveld community of South Africa.
Two exchange visits were undertaken with the support of the Department of Agriculture and an NGO, the Environmental Monitoring
Group, which have led to local economic development and enhanced capacity to manage natural resources in a sustainable manner.
These pilot projects were undertaken within the framework of the Community Exchange and Training Programme of the Global Mechanism
of the United Nations Convention to Combat Desertification (UNCCD). The methodology applied included facilitation to develop
a community-based vision for development, in terms of which the community exchange process was designed. A Facilitation Team
of service providers conducted preparatory workshops, and identified potential partner communities. Two exchange visits were
carried out, one focused on Rooibos production and marketing, and the other on community-based eco-tourism. Following report-back
and planning workshops, emerging community-driven initiatives were supported through their formative stages. The initiatives
have not only resulted in enhanced livelihoods, but the methodology has also been applied widely in a number of different
contexts. 相似文献
903.
The concept of sustainable forest management (SFM) requires forest resource managers to monitor and collect information pertaining to their environmental, economic and social impact. There are increasing expectations from a variety of publics (government, customers, and other stakeholders) that forests be demonstrably well-managed, creating incentives for forest managers to design credible systems for assessing their management performance. It is against this background that local, national and international approaches to regulating forest practices have been evolving. This article reviews the different dimensions of governance as they relate to monitoring and information reporting in the forest sector. Specifically, it discusses the changing role of sovereignty, the effects of globalization and the emergence of civil society stakeholders in forestry-related decision-making. Concepts such as sovereignty and globalization have important implications for monitoring forest practices and for defining SFM. Whether SFM standard creation and enforcement involves a sovereign, shared-sovereignty or civil society approach will affect the level and nature of SFM monitoring. As a result, we need to better consider the concept of monitoring appropriate to the scale and intensity of operations, how monitoring and information reporting standards differ between jurisdictions, and what this means for independently verifying SFM at an inter-jurisdictional level. 相似文献
904.
Combating desertification requires the involvement of many people ranging from communities who experience the effects on a
daily basis and scientists attempting to understand the biophysical and socio-economic causes and consequences of desertification,
to developers and policy makers on all levels. In many instances, however, the understanding, approaches and actions of these
different groups contradict rather than support one another. Over the period 2000 to 2002, a conference process undertaken
in southern Africa brought together communities, scientists, and development workers to test the concept that they could connect
and work together to combat desertification, given an appropriate framework. The conference was a success, and communities,
scientists and developers did exchange experience, knowledge and information. Many lessons were learned, although some pitfalls
were experienced. Time, funding, enhanced communication, and good will are the primary ingredients for ensuring that different
sectors complement one another in their efforts to combat desertification. 相似文献
905.
利用美国陆地资源卫星TM5遥感信息,调查分析了鞍山市森林资源现状。结果表明,鞍山市共有森林资源466933.52hm^2,占全市土地面积的50.32%,其中灌木林占森林面积的81.11%。在此基础上,分析了存在的主要问题,并提出了恢复途径及生态建设模式。 相似文献
906.
907.
Miroslav Jicha Jiri Pospisil Jaroslav Katolicky 《Environmental monitoring and assessment》2000,65(1-2):343-351
A 3-D Eulerian-Lagrangian approach to moving vehicles is presented that takes into account the traffic induced flow rate and turbulence. The method is applied to pollutants dispersion in a street canyon. The approach is based on CFD calculations using Eulerian approach to the continuous phase and Lagrangian approach to the "discrete phase" of moving objects - vehicles. A commercial CFD code StarCD was used into which the Lagrangian model was integrated. As an example a street canyon is taken into consideration. It has the length of 50 m and the aspect ratio of 1.27. The speed of wind was assigned values of 4, 7 and 12 m/s at the altitude of 300 m. The total height of the domain is 115 m. In the study different traffic situations are considered, namely one-way and two-way traffic with different traffic rates per lane. The predictions show that different traffic situations affect pollutants dispersion in the street canyon and that there are also differences in the pollutants dispersion in case of one- and two-way traffic. 相似文献
908.
玉溪市中心城区土地利用布局及其优化研究 总被引:3,自引:0,他引:3
本文系统分析了玉溪市中心城区土地利用强度、土地利用效率、土地利用结构的现状 ,研究了玉溪市中心城区土地利用优化对策 ,探索在城市总体布局中 ,如何充分利用地形特点 ,从可持续发展的角度出发 ,创造舒适宜人的城市生态环境空间。 相似文献
909.
额济纳绿洲生物多样性保护与可持续发展对策研究 总被引:1,自引:0,他引:1
本文论述了额济纳绿洲生物多样性的基本内涵与保护价值,提出保护绿洲生物多样性的措施及策略。 相似文献
910.