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971.
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
972.
BIOMONITORING OF AIR POLLUTION IN A SEASONALLY DRY TROPICAL SUBURBAN AREA USING WHEAT TRANSPLANTS 总被引:3,自引:0,他引:3
Air pollution has been identified as a serious problem throughout the world which causes tremendous loss to the crops by affecting plant growth and yield. Earlier, air pollution was restricted to urban and industrial regions. Over the last few decades, however, it has become evident that pollutants can be transported over long distances and hence their impact may be felt widely over rural areas. The present study was conducted to evaluate the impact of urban air pollution on suburban agriculture with respect to the changes in photosynthetic rate, stomatal conductance, water-use efficiency, plant height, numbers of tillers, leaves, ears and seeds, chlorophyll, carotenoid, protein, phenol, ascorbic acid, nitrogen and sulphate-sulphur contents and seed weight of pot-grown wheat plants (Triticum aestivum var. HUW 468) kept at different sites around Varanasi city receiving varying levels of pollution load. Mean concentrations of were monitored. The study clearly showed that plants are negatively affected by the ambient levels of air pollutants. Reduction in various parameters directly corresponded with the air pollution levels at different sites. 相似文献
973.
Uri ND 《Environmental monitoring and assessment》2001,66(3):293-312
Soil erosion has both on-farm and off-farm impacts. Reductionof soil depth can impair the lands productivity, and thetransport of sediments can degrade streams, lakes, and estuaries. Since 1933, soil conservation policies have existedin the United States. Originally they focused on the on-farmbenefits of keeping soil on the land and increasing net farmincome. Beginning in the 1980s, however, policy goalsincreasingly included reductions in off-site impacts of erosion.As a consequence of conservation efforts associated withexplicit U.S. government policies, total soil erosion between1982 and 1992 was reduced by 32% and the sheet and rillerosion rate fell from an average of 4.1 tons per acre per yearin 1982 to 3.1 tons per acre in 1992 while the wind erosion ratefell from an average of 3.3 tons per acre per year to 2.4 tonsper acre per year over the same period. Still, soil erosion isimposing substantial social costs. These costs are estimated tobe about $37.6 billion annually. To further reduce soil erosionand thereby mitigate its social costs, there are a number ofpolicy options available to induce farmers to adopt conservationpractices including education and technical assistance, financial assistance, research and development, land retirement, andregulation and taxes. 相似文献
974.
Integration of Case Studies on Global Change by Means of Qualitative Differential Equations 总被引:2,自引:0,他引:2
We present a novel methodology to integrate qualitative knowledge from different case studies on Global Change related issues
into a single framework. The method is based on the concept of qualitative differential equations (QDEs) which represents
a mathematically well-defined approach to investigate classes of ordinary differential equations (ODEs) used in conventional
modeling exercises. These classes are defined by common qualitative features, e.g., monotonicity, signs, etc. Using the QSIM-algorithm
it is possible to derive the set of possible solutions of all ODEs in the class. By this one can formulate a common, qualitatively
specified cause–effect scheme valid for all case studies. The scheme is validated by testing it against the actually observed
histories in the study regions with respect to their reconstruction by the corresponding QDE. The method is outlined theoretically
and exemplary applied to the problem of land-use changes due to smallholder agriculture in developing countries. It is shown
that the seven case-studies used can be described by a single cause–effect scheme which thus constitutes a pattern of Global Change. As a generally valid prerequisite for sustainability of this kind of land-use the presence of wage labor is shown to represent
a decisive factor.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
975.
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
976.
The Thar Desert of western India is known for its rich and ancient culture system and traditions. The communities have long
been part of the Thar Desert ecosystem and have evolved specific strategies to live in harmony with its hostile environment.
This culture has provided several miracle plants of immense food and medicinal value to modern civilisation. The ancient rural
livelihood knowledge system reflects time-tested techno-scientific knowledge with a proven track record of sustainability,
especially during natural hazards like drought and famines. In addition, several of the traditional skills of local communities
in arts and crafts, music and instruments have made modern man aware of the art and techniques of sustainably utilising local
biological resources and preserving their biodiversity along with using waste products of the forests, without harming the
desert ecosystem. Traditional cultural and socio-religious values are fast dwindling under the impact of materialistic approach,
industrialisation and development. This paper endeavours to illustrate the need to assist and propagate indigenous rural livelihood
systems rather than mindlessly replace or abandon them as a result of state bureaucracies. 相似文献
977.
The water quality of the Vrgorska Matica River 总被引:1,自引:0,他引:1
Stambuk-Giljanović N 《Environmental monitoring and assessment》2003,83(3):229-253
The article presents the results of investigations carried out on the 42 km long Vrgorska Matica River, which flows through the 15 km long Vrgorsko polje (polje = field) which covers an areaof 3000 ha, and is at 24 m a.s.l., located in Southern Croatia.It covers the years 1997–2000 after this field had been reclaimed for agricultural use.The purpose of the investigations was to evaluate the influence of the Vrgorska Matica River which is part of the catchment areaof the Trebizat River, on the water quality in Modro Oko Lakeand Prud Spring, which are used for water supply and are locateddownstream of the Vrgorska Matica River on the right bank of theNeretva River.The water quality was evaluated by using the quality index basedon the following nine parameters: temperature, mineralization, corrosion coefficient, K = (Cl + SO4)/HCO3, dissolvedoxygen, BOD5, total N, protein N, total phosphorus and totalcoliform bacteria (100 mL)-1 (MPN coli (100 mL)-1) for which concentrations C
95 are calculated. After completingthe nine parameters the results of C
95 were recorded andtransferred to the score table to obtain the q-value. The q-value used is an attempt to quantify environmental factors which would otherwise be qualitative. For each parameter the q-value was multiplied by a weighting factor based upon the relative significance of the parameter. The nine resulting scores values were then added to arrive at an overall water quality index (S95).According to this index the water can be classified into four categories. The first category, according to the Croatian Water Classification Act (Official Bulletin No. 77,1998), includes ground and surface waters used for drinking or in the food industry either in its natural state or after disinfection, and surface water used for raising high-quality species of fish, ranging from 85–100 scores; the second category includes waterused in its natural state for swimming and recreation, sports orfor other species of fish and the treated water used for drinkingand other industrial purposes ranging between 70–85 scores. Thethird category includes water used in industry with no specific requests upon water quality and in agriculture ranging from 50–70 scores; the fourth category includes water used only afterbeing treated in areas with water shortage which is less than 50 scores.According to results obtained by investigations, the water of theVrgorska Matica River and Prud Spring falls into the second (II)category, while water from the Modro Oko Lake belongs to the first (I) category. This means that the Matica River water does not influence the water quality of the Modro Oko Lake. This lakewater quality is influenced by the Rastoka Matica River from theRastoko polje which is located upstream from the Vrgorska MaticaRiver. This has been proved by dyeing tests. 相似文献
978.
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
979.
可持续发展理念下的地质环境承载力初步探讨 总被引:3,自引:1,他引:3
在环境承载力概念的基础上定义了地质环境承载力,讨论了地质环境承载力的内在涵义及特点,以城市地质环境为例,探讨了地质环境承载力评价的工作程序。 相似文献
980.
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