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71.
《Journal of Sustainable Forestry》2013,32(2-3):165-187
Summary It is some years now since forest decline was a major public concern in Europe and was one of the principal environmental issues around which international research programs were focused. A number of internationally coordinated activities were initiated in the 1980s and 1990s and have continued until now; these contributed significantly to our current understanding of forestry and to the way in which forestry policies have developed. In short, the concept of sustainable development has had an increasing influence and is now of immeasurable value in forest policy, with sustainable forest management well established as its guiding principle. This sequence of events is examined here. The extent to which understanding has advanced is remarkable; much has changed. Arguably this period gave the first indication of the extent to which forests and ecosystems globally are threatened by environmental change. On the basis of the last 20 years, it is tempting to conclude that we now have an effective institutional framework and have made excellent progress. However, some of the recorded ecosystem responses seem anomalous; there are surprises in system responses, e.g., the linkage between sulphur and nitrogen depositions and forest growth. Even more importantly some specific pollutant problems remain and will intensify, and climate change has become an environmental issue of overwhelming importance. 相似文献
72.
文章从文化创意产业与旅游业的融合角度着手,以五大连池风景区为例,通过分析五大连池风景区火山与矿泉文化资源,进一步从文化创意与旅游融合的角度提出拓展型融合、渗入型融合、重装型融合的五大连池火山矿泉疗养文化与旅游业的融合模式。 相似文献
73.
Uses of game resources are under constant debate. One such debate focuses on hunting tourism and its contributions to rural economics. To prioritize future investment and inform policy decisions, it is necessary to identify the full economic consequences of the operation of hunting tourism companies in rural areas. However, the true economic significance of these typically small-scale companies is not apparent when examined on an industrial scale. These companies may nevertheless serve as a sustainable solution to local-scale rural challenges. In this article, the regional economic significance of hunting tourism is estimated for the East Lapland sub-region of northern Finland through the use of Computable General Equilibrium simulation models. Although these models are known to effectively evaluate short- and long-term regional economic effects of industries such as tourism, they have not previously been applied to evaluate hunting tourism. 相似文献
74.
Complexity of mutual act and different sensation of different tourists are important factors influencing regional tourism resources evaluation. Fuzzy mathematic method can be used to up quantitative evaluation method on tourism resources evaluation. Taking Wushan Small Three Gorges as an example, the author carries out the evaluation of the tourism resources in the Three Gorges Reservoir. At the same time, the authors consider that five factors, such as improvement of the comunication of tourism resources, quickening the Steps of urbanization in reservior area, must be done well. 相似文献
75.
76.
基于生态系统视角的乡村旅游空间地域性探讨 总被引:1,自引:0,他引:1
沈刚 《干旱区资源与环境》2007,21(9):102-105
尽管人们对乡村旅游作了大量的研究,但对基本概念仍未取得一致。文章在对国内外研究情况综述的基础上,从生态系统的新视角对乡村旅游空间地域性进行了探讨,认为这对相关概念的辨析、指导乡村旅游发展规划等有积极的意义。 相似文献
77.
兰州旅游圈旅游空间结构构建研究 总被引:2,自引:0,他引:2
李建国 《干旱区资源与环境》2007,21(10):118-124
区域旅游空间结构对于区域旅游业的发展具有重要的意义。文章在简要地梳理近些年来区域旅游空间结构研究成果的基础上,对于区域旅游空间结构的构建方法提出了自己的观点:根据游客的到访情况划分其内部结构,根据资源集聚态势和共同表现的主题进行功能分区,按照远近结合的原则确定优先发展区,根据服务功能确定旅游中心地。通过对兰州旅游圈深入的调查和研究,提出兰州旅游圈的空间结构构建模式:三个旅游圈层、七个旅游瓣区和十一个旅游功能区;在综合评价的基础上确定了圈内的七个优先发展区和若干个旅游中心地。最后,对于兰州旅游圈的旅游线路提出了设计方案。 相似文献
78.
森林资源作为国家的重要自然资源,不仅能够创造经济效益,还可以调节整个生态系统.伴随公众环保意识的日益增强,森林资源保护工作受到了社会的广泛关注,国家也采取了一系列措施加强森林资源的保护管理.然而从现实来看森林资源保护工作仍面临着不少问题需要解决.为此,就当前森林资源保护管理存在的主要问题进行了分析,探讨了有效的应对策略... 相似文献
79.
大气中氧化亚氮(N2O)浓度的上升加剧了全球变暖。森林土壤在调节大气N2O浓度中发挥着至关重要的作用。近年来,氮(N)输入对森林土壤N2O通量的影响备受关注。然而,森林土壤N2O排放对N输入响应的机制,尤其是植物和微生物对N2O通量的调控作用尚缺乏系统研究。因此,本文综述了N输入如何通过森林植被(根系N吸收、凋落物分解和形成丛枝菌根)和土壤微生物(微生物量和群落组成)调控N2O产生途径从而影响森林土壤N2O排放。结果表明,植物的竞争性氮吸收能降低氮输入对N2O排放的促进作用,其作用大小可能主要取决于土壤“氮饱和”状态。植物凋落物主要通过分解过程中的养分归还和次生代谢产物释放来影响氮输入背景下的森林土壤N2O排放,前者具有促进作用,而后者具有抑制作用。丛枝菌根主要通过吸收有效氮和水分、促进团聚体形成以及改变N2O相关功能基因群落调控森林土壤N2O通量。N输入导致的土壤酸化或养分限制,通常会降低微生物量和/或改变微生物群落组成,从而控制N2O排放。N输入对N2O不同产生途径也会造成影响,受土壤湿度、N2O底物浓度以及N2O相关功能基因丰度(AOB、 AOA、nirK、 nirS和nosZ)的调控。未来在模型预测中,需要将植物氮吸收、凋落物分解、菌根以及N2O产生途径充分纳入模型,以提高模型预测准确性,为全球变化背景下制订森林管理政策和温室气体减排措施提供支持。 相似文献
80.
The composition of arbuscular mycorrhizal fungi (AMF) communities found in agricultural systems has been found to be very different to that of forest. The implications of this, if any, for the restoration of indigenous forest on ex-agricultural land is poorly understood. This study investigated the effect that AMF communities isolated from ex-agricultural and forest soils have on the growth of an indigenous New Zealand tree species (Podocarpus cunninghamii). The forest AMF community was isolated from a remnant stand of P. cunninghamii forest and the ex-agricultural AMF from a retired grazing grassland. In addition, the study examined how the two AMF communities affected the competitiveness of P. cunninghamii when grown in competition with an invasive grass species (Agrostis capillaris), which is frequently dominant on ex-agricultural land in New Zealand. P. cunninghamii growth was significantly decreased by inoculation with ex-agricultural AMF compared to forest AMF. Furthermore, the forest AMF community was able to significantly increase P. cunninghamii root production when in competition with A. capillaris. The findings suggest that when attempting to restore indigenous forest on ex-agricultural land, inoculation of tree seedlings with appropriate forest AMF may improve their growth and survival. 相似文献