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491.
Integrating nature-based tourism and forestry in private lands under heterogeneous visitor preferences for forest attributes 总被引:1,自引:0,他引:1
Erkki Mäntymaa Ville Ovaskainen Artti Juutinen Liisa Tyrväinen 《Journal of Environmental Planning and Management》2018,61(4):724-746
Developing nature-based tourism in private lands calls for new mechanisms to consolidate the interests of the tourism industry, visitors, and landowners. This choice experiment study elaborates on the heterogeneity of visitors’ preferences and willingness to pay (WTP) for enhanced forest amenities and ecosystem services. The survey, targeting domestic and foreign tourists visiting the Ruka-Kuusamo area in Finland, considered four attributes: landscape quality, outdoor routes, forest biodiversity, and carbon sequestration. For observed heterogeneity, the visitors were grouped by their attitudes towards forest management. Unobserved heterogeneity in visitors’ choice behaviour and WTP was examined with the latent class model. While most visitors had environmentally friendly attitudes and were willing to pay, especially for enhanced landscape quality and biodiversity, considerable heterogeneity was revealed in terms of three segments with distinctive attitudes, choice behaviour and WTP. The variation in WTP has important implications for the design of a scheme of payments for environmental management. 相似文献
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493.
文章阐述了目前国内外对干法脱硫渣综合利用的现状,以胶凝材料学以及水泥化学为理论基础,将干法脱硫渣中的物质划分为三类,并提出在充分激发其活性的基础上,对干法脱硫渣进行高技术附加值的利用,并详细阐述了其原理和途径。 相似文献
494.
通过对青海杨的两个分别来自极端干旱和湿润地区的种群进行不同水分处理,研究其在生物量的积累与分配、气体交换、脱落酸积累以及水分利用效率上的种群差异.结果表明:①不同种群在各种生长和形态指标上均表现出了显著性差异,例如株高(Ht)、基径(Bd)、总生物量(Tb)、总叶面积(La)和细根比(Ft).②不同种群在各种生理指标上也表现出了显著性差异,例如净光合速率(A)、蒸腾速率(E)、气孔导度(g)、水分利用效率(WUEi)和脱落酸(ABA)积累.③与来自湿润地区的种群相比,来自干旱地区的种群表现出了较小的生长和形态指标值以及较大的生理指标值.这些对水分可利用性的形态和生理适应性表明,不同种群在其幼苗早期生长和建立方面采用了不同的生存策略,来自湿润地区的杨树种群采用耗水策略从而抗旱性低,而来自干旱地区的杨树采用节水策略从而抗旱性高.这些对干旱的不同反应可以为不同气候地区选择相应的生态型提供一定的参考标准.表4参26 相似文献
495.
赵承开 《湖南环境生物职业技术学院学报》1997,(1)
今天,美国许多林业工作者正在研究城市林业。城市居民和社会团体每天都要接触都市环境,管理和使用城市林业资源,因此,城市林业与市民的关系是非常密切的。其相互作用也是非常重要的。 城市林业资源的管理和使用与普通林业有广泛地联系,有时,市民们是直接按普通林业的方式来管理城市林业的。 本文论述了在城市环境中,市民与城市林业的关系、说明了城市林业的多种效益、提出了与城市林业有关的一些论点。 相似文献
496.
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498.
Barker JR Bollman M Ringold PL Sackinger J Cline SP 《Environmental monitoring and assessment》2002,75(1):57-78
This article evaluates the performance of a protocol to monitor riparian forests in western Oregon, United States based on thequality of the data obtained from a field survey. Precision isthe criteria used to determine the quality of 19 field and 6 derived metrics. The derived metrics were calculated from thefield data. The survey consisted of 110 riparian sites on publicand private lands that were sampled during the summers of 1996 and 1997. In order to calculate metric precision, some of the field plots were re-measured. Metric precision was defined in terms of the coefficient of variability (CV) and standard deviation and then compared with a pre-defined data quality objective (DQO). A metric was considered precise if the CV met or exceeded the DQO. The geomorphology metrics were not precisewhile the forest stand inventory metrics and forest cover metrics, with some exceptions, were precise. The precision formany of the field and derived metrics compared favorably withthe level of precision for similar metrics reported in the literature. Recommendations are made to improve the precision for some metrics and they include changing the way precision is calculated, re-defining the field protocol, or improving field training. 相似文献
499.
N. J. Snyder S. Mostaghimi D. F. Berry R. B. Reneau S. Hong P W. McClellan E. P. Smith 《Journal of the American Water Resources Association》1998,34(2):385-395
ABSTRACT: A field monitoring study of a riparian forest buffer zone was conducted to determine the impact of the riparian ecosystem on reducing the concentration of agricultural nonpoint source pollutants. Groundwater samples were collected from 20 sampling locations between May 1993 and December 1994, and analyzed for NO3-N, PO4, and NH4-N. Statistical analyses such as Friedman's test, cluster analysis, cross correlation analysis and Duncan's test were performed for the nutrient data. The study showed that the ripanan buffer zone was effective in reducing nitrate concentrations originating from upland agricultural fields. Instream nitrate concentrations were 48 percent less than those measured in the agricultural field. Reductions in concentrations in sampling locations at the wetland edge ranged from 16 to 70 percent. The mean nitrate concentrations in forested hill slope were 45 percent less than concentrations in a well located in an upland agricultural field. Meanwhile, the concentrations of phosphate and ammonia did not follow any specific spatial trend and were generally higher during the summer season for most sampling locations. 相似文献
500.
T. K. Vlassova 《Mitigation and Adaptation Strategies for Global Change》2006,11(4):897-909
Three methods of gathering local and traditional knowledge of Indigenous Peoples were used to assess environmental changes
and human impacts in Russian boreal forest communities: structured interviews, followed by an unstructured interview, and
an education/training workshop. The most important environment changes reported by Indigenous Peoples included the disappearance
of animals and plants, climate changes, a decrease in forest and shrub area, and human impacts such as poaching, forests fires,
industrial logging, clearing of forests for firewood, and water pollution by industrial wastes and discharges. We propose
establishment of the Boreal Residents' Network for Socio-environment Assessments and Education for Sustainable Development
to acquire local and traditional knowledge as a supplement to scientific monitoring. The proposed approach would involve permanent
inhabitants living in a broad range of boreal forests to gather local and traditional knowledge and assessments. This could
lead to a meta-database to share with international networks. 相似文献