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311.
Abstract: Intense deforestation causes massive species losses. These losses occur because the habitats supplanting primary forest are inadequate to sustain viable populations of forest-dependent species. Despite this, certain species do seem to persist within the secondary habitats that replace original forest. This implies that there is a special class of species that might survive the loss of primary forest. Such a result would significantly influence conservation plans and extinction predictions. We tested whether species that tolerate secondary habitats survive extensive habitat loss and whether the same degree of loss threatens species that are forest obligates. To identify purported "survivors," we compared the remaining range sizes of endemic birds, their abundances, and their degree of extinction threat. We did this within the remaining Atlantic Forest of Brazil, a region extremely rich in endemics but with only approximately 10% of its forest remaining. We found no survivors. Habitat loss threatens forest-obligate birds and those using secondary habitats equally. 相似文献
312.
To improve the efficiency of the carbon dioxide cycling process and to reduce the regeneration energy consumption, a sterically hindered amine of 2-amino-2-methyl-1-propranol (AMP) was investigated to determine its regeneration behavior as a CO_2 absorbent. The CO_2 absorption and amine regeneration characteristics were experimentally examined under various operating conditions. The regeneration efficiency increased from 86.2% to 98.3% during the temperature range of 358 to 403 K. The most suitable regeneration temperature for AMP was 383 K, in this experiment condition, and the regeneration efficiency of absorption/regeneration runs descended from 98.3% to 94.0%. A number of heat-stable salts (HSS) could cause a reduction in CO_2 absorption capacity and regeneration efficiency. The results indicated that aqueous AMP was easier to regenerate with less loss of absorption capacity than other amines, such as, monoethanolamine (MEA), diethanolamine (DEA), diethylenetriamine (DETA), and N-methyldiethanolamine (MDEA). 相似文献
313.
Fungal activity is thought to play a direct and effective role in the breakdown and dissolution of primary minerals and in the synthesis of clay minerals in soil environments, with important consequences for plant growth and ecosystem functioning. We have studied primary mineral weathering in volcanic soils developed on trachydacite in southern Tuscany using a combination of qualitative and quantitative mineralogical and microbiological techniques. Specifically, we characterized the weathering and microbiological colonization of the magnetically separated ferromagnesian minerals (biotite and orthopyroxene) and non-ferromagnesian constituents (K-feldspar and volcanic glass) of the coarse sand fraction (250-1,000 microm). Our results show that in the basal horizons of the soils, the ferromagnesian minerals are much more intensively colonized by microorganisms than K-feldspar and glass, but that the composition of the microbial communities living on the two mineral fractions is similar. Moreover, X-ray diffraction, optical and scanning electron microscope observations show that although the ferromagnesian minerals are preferentially associated with an embryonic form of the clay mineral halloysite, they are still relatively fresh. We interpret our results as indicating that in this instance microbial activity, and particularly fungal activity, has not been an effective agent of mineral weathering, that the association with clay minerals is indirect, and that fungal weathering of primary minerals may not be as important a source of plant nutrients as previously claimed. 相似文献
314.
Fobissie B. Kalame Johnson Nkem Monica Idinoba Markku Kanninen 《Mitigation and Adaptation Strategies for Global Change》2009,14(2):135-151
Many studies have suggested various kinds of forest policies, management planning and practices to help forests adapt to climate
change. These recommendations are often generic, based mostly on case studies from temperate countries and rarely from Africa.
We argue that policy and management recommendations aimed at integrating adaptation into national forest policies and practices
in Africa should start with an inventory and careful examination of existing policies and practices in order to understand
the nature and extent of intervention required to influence the adaptation of forest ecosystems to climate change. This paper
aims to contribute to closing this gap in knowledge detrimental to decision making through the review and analysis of current
forest policies and practices in Burkina Faso and Ghana and highlighting elements that have the potential to influence the
adaptation of forest ecosystems to climate change. The analysis revealed that adaptation (and mitigation) are not part of
current forest policies in Burkina Faso and Ghana, but instead policies contain elements of risk management practices which
are also relevant to the adaptation of forest ecosystems. Some of these elements are found in policies on the management of
forest fires, forest genetic resources, non-timber resources, tree regeneration and silvicultural practices. To facilitate
and enhance the management of these elements, a number of recommendations are suggested. Their implementation will require
experienced and well-trained forestry personnel, financial resources, socio-cultural and political dimensions, and the political
will of decision makers to act appropriately by formulating necessary policies and mainstreaming adaptation into forest policy
and management planning. 相似文献
315.
基于生态绿当量的开封土地利用研究 总被引:1,自引:0,他引:1
基于生态绿当量的提出与模型的建立,计算水田、旱田、园地和林地的生态绿当量,得到研究区域的综合绿当量,并将该值与以最佳森林覆盖率的生态优化标准进行比较。对研究区域的土地利用结构进行现状评价,在此基础上对研究区域土地利用结构进行优化调整。以开封为例,针对开封土地利用问题,提出优化方案,以期达到经济、社会和生态效益的统一。 相似文献
316.
TiO2晶须在深度净化饮用水过程中失活原因分析 总被引:1,自引:0,他引:1
研究了TiO2晶须在光催化深度净化饮用水过程中失活的原因及相应的再生方法.对TiO2薄膜失活前后的AFM、XRD表征,以及对失活前后TiO2晶须酸洗液的ICP分析表明,TiO2晶须失活的主要原因是难溶性碳酸钙在催化剂表面的沉积.由于自来水中钙离子的存在以及有机物光催化降解过程中产生的二氧化碳,生成的难溶性碳酸钙覆盖在催化剂的表面,影响了紫外光的透光率,限制了光生电子和光生空穴的生成,导致催化剂的光催化能力逐渐下降直至失活;失活的催化剂通过1 mol/L的盐酸酸洗4 h后,光催化活性可以恢复到95%左右;多次失活/再生的催化剂的光催化活性保持较好的稳定性. 相似文献
317.
Land-use change due to socioeconomic factors leads to the abandonment of traditional intensive coppice management in large areas of the mountainous landscapes of the Apennines (Italy). In this study we explored the multivariate relationship between plant species traits, stage of forest succession and environmental gradients. We focused on community-level patterns in plant traits of the vegetation of beech forest understory along the regeneration chronosequence initiated after cessation of coppicing. We hypothesized that the correlations between the traits and environmental factors should increase with succession age due to the decreasing role of chance.Landscape-level heterogeneity, i.e. changing elevation, slope, exposition, bedrock and forest stand age was assessed using a stratified random sampling design. Sixty sites were sampled for stand structure and species composition. We focused on 14 plant traits related to persistence, growth and dispersal. The recently developed data-analytical method, Model-Based Recursive Partitioning, was used to disentangle the relationships between patterns of plant traits and environmental gradients.About half (seven) of the studied plant traits showed significant correlations with succession stand age, elevation, inclination, heat index and bedrock. Contrary to the low number of trait-environment correlations in early succession, eight traits showed significant relationships with one or more abiotic factors in older stages of the post-coppice development. Stand age had the highest independent explanatory power, explaining 40% of variance of SLA, more than 17% of variance of short-distance seed dispersal and more than 15% of variance of both long-term connection and extensive perennial root. Among the other abiotic factors, elevation explained 27% of variance of SLA, inclination explained 6-8% of variance of long-term connection, extensive perennial root, thickening and large bud bank.The observed trait-environmental relationship is assumed to be driven by various environmental factors operating at various levels of complexity. While forest succession in relatively homogeneous landscapes might be driven mainly by environmental factors related to forest succession itself and associated abiotic changes (such as changes in light and soil moisture patterns), in heterogeneous landscapes the succession pathways may be structured by landscape-level environmental factors such as inclination. However, in the present study, forest stand age had the highest explanatory power for most of the investigated traits, supporting the assumption of the overall strong impact of succession-driven environmental factors in trait-environment relationships. 相似文献
318.
Marileena KoskelaAuthor Vitae 《Journal of Cleaner Production》2011,19(12):1365-1376
The paper argues that corporate environmental management should be based on significant environmental aspects that result in significant environmental impacts. The Finnish forest industry has substantially reduced its emissions but, being heavy industry, it still causes significant environmental impacts. This paper presents expert views on environmental impacts and their measurement. They were gathered through semi-structured theme interviews. The most frequently mentioned environmental impacts and significant environmental impacts related to water, energy and air. Positive environmental impacts resulted from recycling, forest industry products and use of energy. Traditional emission measurement was considered a well-measured issue. The target subjects of the measurement and especially environmental impact measurement require improvement. The contribution of this research is concerned with the development of measurement and two issues arising from the research are emphasised. First, environmental impact measurement should be further developed. Second, the measurement of the production chain that is physically outside the boundaries of forest industry mills should also be developed. 相似文献
319.
Eeva Primmer 《Journal of Cleaner Production》2011,19(16):1822-1832
Integrating biodiversity conservation into forest management requires changes in the practices of those public and private actors that have implementing responsibilities and whose strategic and operational opportunities are at stake. Understanding this kind of context-dependent institutional adaptation entails bridging between two analytical approaches: policy implementation and organizational adaptation. This article combines these two approaches by reviewing them, and their caveats, and by summarizing empirical analyses of organizational competences, specialization, professional judgment, and organizational networks in the organizational field of non-industrial private forestry in Finland. Drawing on these theoretical and empirical analyses, the article discloses the broad phenomenon of institutional adaptation in the integration of biodiversity conservation and forest management. The empirical analyses point to the dominance of hierarchical policy implementation over strategic organizational adaptation. Together with the detected isomorphism of professional norms and networks, these contribute to meeting minimum standards but can constrain the ways in which the organizations and professionals respond to the challenge of biodiversity conservation. The detected inertia signals lack of alertness. It is perhaps also an indication of self-sufficiency among the actors. The interpretation of these responses to challenges and responsibilities across the public and private sector boundaries demonstrates the necessity of combining the two traditionally segregated approaches. 相似文献
320.
以奥运森林公园南区景观水系为背景,探讨了如何建立基于自动监测的水质预警体系.水质预警体系中包含5个部分:风险因素自动识别、风险因素定量化分析和预测、水质预测、水质警报指标体系与水质预警、对策及防范措施.结合奥运森林公园南区景观水系的具体情况,分析了上述水质预警体系中各部分的主要实现方法,给出了动态率定法、统计模型法、机... 相似文献