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41.
Shemdoe Riziki Silas 《中国人口.资源与环境(英文版)》2016,14(1):38-44
This paper presents results of the assessment on benefit sharing and payment mechanisms tested by six non-governmental organizations (NGOs)-piloted Reducing Emissions from Deforestation and Forest Degradation (REDD+) initiatives in Tanzania. Results from the assessment indicate that models applied by most of the REDD+ pilot projects have provided most of decisions for the distribution of benefits to the communities through village general assemblies. Based on requirements of the tested models, national benefit-sharing mechanism models are proposed. Major attributes to be considered in the development of national benefit-sharing models should include: (i) ensuring that the existing government structure is not excluded to ensure sustainability; (ii) village general assembly is involved in determining the distribution of the benefits accrued; and (iii) transparency in handling the carbon finance is ensured. Models that are proposed for the national REDD+ benefit sharing apply to two forest management systems, namely Joint Forest Management (JFM) and Community Based Forest Management (CBFM). The paper recommends testing of the two proposed models to determine whether they could be useful in sharing benefits resulting from REDD+ in Tanzania. 相似文献
42.
Gert Jan Reinds Maximilian Posch 《Environmental pollution (Barking, Essex : 1987)》2009,157(4):1258-1269
The dynamic soil chemistry model SMART was applied to 121 intensive forest monitoring plots (mainly located in western and northern Europe) for which both element input (deposition) and element concentrations in the soil solution were available. After calibration of poorly known parameters, the model accurately simulated soil solution concentrations for most plots as indicated by goodness-of-fit measures, although some of the intra-annual variation especially in nitrate and aluminium concentrations could not be reproduced. Model evaluations of two emission-deposition scenarios (current legislation and maximum feasible reductions) for the period 1970-2030 show a strong reduction in sulphate concentrations between 1980 and 2000 in the soil due to the high reductions in sulphur emissions. However, current legislation hardly reduces future nitrogen concentrations, whereas maximum feasible reductions reduces them by more than half. Maximum feasible reductions are also more effective in increasing pH and reducing aluminium concentrations, mostly below ‘critical’ values. 相似文献
43.
Dölarslan ES 《Journal of environmental management》2009,90(1):25-35
This paper reviews the effects of six post-modern management concepts as applied to Turkish forestry. Up to now, Turkish forestry has been constrained, both in terms of its operations and internal organization, by a highly bureaucratic system. The application of new thinking in forestry management, however, has recently resulted in new organizational and production concepts that promise to address problems specific to this Turkish industry and bring about positive changes. This paper will elucidate these specific issues and demonstrate how post-modern management thinking is influencing the administration and operational capacity of Turkish forestry within its current structure. 相似文献
44.
Frank Merry Britaldo Soares-Filho Daniel Nepstad Gregory Amacher Hermann Rodrigues 《Environmental management》2009,44(3):395-407
Logging has been a much maligned feature of frontier development in the Amazon. Most discussions ignore the fact that logging
can be part of a renewable, environmentally benign, and broadly equitable economic activity in these remote places. We estimate
there to be some 4.5 ± 1.35 billion m3 of commercial timber volume in the Brazilian Amazon today, of which 1.2 billion m3 is currently profitable to harvest, with a total potential stumpage value of $15.4 billion. A successful forest sector in
the Brazilian Amazon will integrate timber harvesting on private lands and on unprotected and unsettled government lands with
timber concessions on public lands. If a legal, productive, timber industry can be established outside of protected areas,
it will deliver environmental benefits in synergy with those provided by the region’s network of protected areas, the latter
of which we estimate to have an opportunity cost from lost timber revenues of $2.3 billion over 30 years. Indeed, on all land
accessible to harvesting, the timber industry could produce an average of more than 16 million m3 per year over a 30-year harvest cycle—entirely outside of current protected areas—providing $4.8 billion in returns to landowners
and generating $1.8 billion in sawnwood sales tax revenue. This level of harvest could be profitably complemented with an
additional 10% from logging concessions on National Forests. This advance, however, should be realized only through widespread
adoption of reduced impact logging techniques. 相似文献
45.
Ecological disturbances of forests by insects have a complex array of associated human dimensions presenting complications
for natural resource decision making and relationships between stakeholders and managers. This article discusses the human
context of forest disturbances by insects by reviewing four cases of bark beetle forest disturbance from British Columbia
in Canada, Bavarian Forest National Park in Germany, the Kenai Peninsula in Alaska, and the north central region of Colorado.
Findings and lessons learned from these studies are outlined along with their implications for managing forest disturbances
by insects in general. Conclusions focus on the need to assess the broad array of impacts and risks perceived by local residents
and the capacity for local action and involvement in managing forest disturbances. Communication and interaction between resource
managers and local stakeholders can facilitate the identification of management priorities and potentially reduce some of
the risks associated with forest disturbances by insects. 相似文献
46.
Fertilization with 2.5 t/ha limestone: (83% CaCO3, 8% MgO, 6% K2O, 3% P2O5) reduces the 137Cs transfer from spruce forest soil into plants like fern (Dryopteris carthusiana) and blackberry (Rubus fruticosus) by a factor of 2–5 during at least 11 years as measured by the aggregated transfer factor Tag. In 1997 and 2006 these results were confirmed by additional measurements of the 137Cs transfer factor TF, related to the root zone (Oh horizon), which were explained by the selective sorption of 137Cs in the root zone by measurements of the Radiocaesium Interception Potential (RIP) in fertilized (RIP > 179 meq/kg) and non-fertilized soils (RIP < 74 meq/kg). 相似文献
47.
The results of studies on postfire succession in larch forests of the permafrost zone are discussed. The main directions of successional processes in burned-out areas of different ages are described. It has been shown that secondary pyrogenic successions in larch forests follow the scheme of rapid regeneration without tree species replacement and the model of succession tolerance. Groups of plant species with different life strategies and indicator species characterizing different stages of the overgrowing of burned-out areas have been identified. 相似文献
48.
Yu Y Wen S Lü H Feng Y Wang X Sheng G Fu J 《Environmental monitoring and assessment》2008,137(1-3):275-285
The diurnal variation of atmospheric carbonyls and VOCs in a forest in south China were studied in summer 2004. Twenty kinds
of carbonyls and eight kinds of VOCs were identified and quantified. Formaldehyde and acetaldehyde were the two most abundant
carbonyls, while the most abundant VOCs were isoprene, followed by o-xylene. Most C3-C10 carbonyls had higher concentrations from 09:00 to 15:00, and their levels were lower during night-time and often reached
the lowest in early morning. Formaldehyde and acetaldehyde, however, showed two high levels in their diurnal patterns partly
due to their different sources and sinks. The VOCs had different diurnal patterns compared to most carbonyls. The highest
concentrations were observed from 03:00 to 06:00 for 1-butene, from 06:00 to 12:00 for isoprene, and from 12:00 to 15:00 for
α-pinene. The highest levels for aromatic hydrocarbons occurred during midnight and the lowest in late afternoon. According
to the study, emissions from vegetation and photo-oxidation of gas-phase hydrocarbons were the main sources for some carbonyls
and VOCs in this region. Other compounds, such as formaldehyde, acetaldehyde and BTEX, showed anthropogenic sources. 相似文献
49.
We propose a stochastic dynamic programming framework to model the management of a multi-stand forest under climate risk (strong
wind occurrence). The preferences of the forest-owner are specified by a non-expected utility in order to separately analyze
intertemporal substitution and risk aversion effects. A numerical method is developed to characterize the optimal forest management
policies and the optimal consumption-saving strategy. The stochastic dynamic programming framework is applied to a non-industrial
private forest-owner located in North-East of France. We show that the optimal decisions both depend upon risk and time preferences.
The authors would like to thank participants at the international conference on Economics of Sustainable Forest Management
in Toronto, at the PARIS 1 seminar on Environmental and Natural Resource Economics, at the 2004 Applied Microeconomics Conference
in Lille and at the 13th annual conference of the European Association of Environmental and Resource Economists at Budapest. 相似文献
50.
废塑料处理技术进展与展望 总被引:10,自引:0,他引:10
文章介绍了解决废塑料污染的几种方法,分析了目前我国废塑料回收利用技术的现状,并介绍作者在这方面进行的一些新的研究工作:(1)使用自制的催化剂完成了聚烯烃类塑料催化热解回收燃料油的小试,获得了较好的效果;(2)通过实验对发泡聚苯乙烯热解回收苯乙烯单体的工艺流程提出了优化操作条件。根据国内外实际,文章最后对废塑料回收利用提出了几点建议。 相似文献