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91.
In high-income countries depression and cardiovascular diseases were predicted to be the two leading causes of DALYs in the year 2030. Private-life stress fosters both kinds of diseases. Scientific findings already show that forest exposure has stress-reducing effects. Particularly in Japan, people have practiced forest bathing to improve their health. The German population also has a strong connection to its forests, and forest law allows forest access, regardless of ownership structure. Hence, the question arises of whether forest exposure could be used in Germany as a kind of stress-coping strategy. To a certain degree, the success of such a strategy in Germany would require the participation of the stakeholders that are active in both the health and the forestry sectors. Therefore, it seems necessary to gain insight into German forest and health professionals' understanding and attitude concerning forest-related health benefits. For this reason, in this pilot study, guideline interviews with professionals of both sectors and with professionals standing in between these professions were conducted, recorded and transcribed. On the one hand, each professional’s presumptions regarding the health-fostering effects of forests were investigated, derived from their subjective certainty that forest exposure has health-fostering effects. In addition, a thought experiment was used to estimate the level of willingness to cooperate with each other in order to motivate people to be physically active in forests. For analysis, Mayring’s qualitative content analysis and a frequency analysis (MaxQDA) were applied. Findings show that most of the interviewed professionals presume forests to have health-fostering effects. Furthermore, something derived from the statements within the context of the thought experiment was that most professionals seem to be willing to cooperate with the other sector. Hence, it might be conceivable that forest exposure may be part of a German stress-coping strategy.  相似文献   
92.
乡村旅游产业发展契合了乡村振兴战略的基本要求,以可持续发展视角关注乡村旅游业的多重价值,为乡村产业融合、经济发展和农民就业增收提供了持久动力。基于一体化乡村旅游(IRT)框架理论,以山东省乡村旅游典型村为研究对象,运用案例分析方法探究乡村旅游协同发展的内在基础与阶段特征,剖析乡村旅游协同发展的驱动机制与实现路径。结果表明,乡村旅游初始发展阶段依赖于资源内生性与利益共享性,市场化运作阶段强调组织化嵌入与规模化经营,快速扩张阶段关注社区赋权与内生性发展,持续发展阶段诉求利益均衡与合作共生。社区参与、多元赋权与价值认同,多利益相关者的参与、联合与协同,持续、有效的制度性供给与规范是乡村旅游协同发展的运行基础。但是,乡村旅游不同发展阶段面临着多元主体利益不均衡、资源内生性不足、乡土文化异化、社区赋权程度低和城乡要素流动不畅等问题与挑战。因此,提出合作网络构建与协作经营机制、多元主体的利益协调机制、乡村社会文化的保护与建构机制、资本嵌入与竞合机制等协同发展路径。  相似文献   
93.
Summary The effect of liming on in-situ N transformations was studied in two stands of different ages of each of Scots pine (Pinus sylvestris L.), Douglas fir [Pseudotsuga menziesii (Mirb.) Franco], and common oak (Quercus robur L.). The stands were located on acid sandy soils in an area with high atmospheric N input. The organic matter of the upper 10-cm layer of the soil, including the forest floor, had a relatively high N content (C: N ratio <25) in all stands. Using a sequential core technique, N transformations were measured in both control plots and plots that had been limed 3 years previously with 3 t ha-1 of dolomitic lime. Limed plots had a higher net NO inf3 sup- production and a higher potential for NO inf3 sup- leaching than the controls in all stands except that of the younger oak. Net N mineralization did not differ significantly between limed and control plots in oak stands and younger coniferous stands but was significantly lower in the limed plots of the older coniferous stands. It is concluded that long-term measurements of net N mineralization in limed forest soils are needed to evaluate the effect of liming with respect to the risk of groundwater pollution.  相似文献   
94.
Summary Microbial biomass in the upper 7 cm of soil and needle decomposition on the forest floor were measured seasonally for 10 months in a mountain hemlock (Tsuga mertensiana) old-growth forest and in a regrowth forest after Phellinus weirii, a root-rot pathogen infection, had caused disturbance. The microbial biomass was higher in the old-growth forest soil than in the regrowth forest soil. However, T. mertensiana needle decomposition rates were higher in the regrowth than in the old-growth forest. Total N, Ca, Fe, Cu, and Zn concentrations in needles increased during the 1st year of decomposition in both the old and the regrowth forests, but P, K, Mg, Mn, and B concentrations decreased. N, P, K, Mg, Cu, and Zn concentrations were lower in regrowth than in old-growth decomposing needles. During mineralization, needles in the regrowth forests released more N, P, and K as a result of higher needle decomposition rates. Our results suggest that higher needle decomposition rates increased the mineralization of N, P, and K, which may lead to increased soil fertility and faster tree growth rates in the regrowth forest.  相似文献   
95.
利用层次分析与Fuzzy数学相结合方法,对辽宁省东部山区5种森林植被类型水源涵养能力进行了多目标综合评判。首先利用层次分析法确定了评价因子林冠截留、林冠蒸散、枯落物蓄水、土壤容重、非毛管孔隙度、初渗速率、稳渗速率、土壤总蓄水和土壤有效水的权重集为C=(0.0245,0.0051,0.1993,0.0109,0.0762,0.0565,0.2827,0.0573,0.2866),然后利用最大模糊熵原则确定了评价因子的隶属函数,最后利用Fuzzy综合评判得出油松、落叶松、红松、柞木林、杂木林评价结果模糊子集为B=(0.4686,0.3784,0.4145,0.6128,0.4808),结果表明阔叶林水源涵养效益高于针叶林,其中柞木林效益最佳。  相似文献   
96.
In order to examine the effects of disturbance, vegetation type, and microclimate on denitrification and denitrifier community composition, experimental plots were established at the H. J. Andrews Experimental Forest in the Cascade Mountains of Oregon. Soil cores were reciprocally transplanted between meadow and forest and samples were collected after 1 and 2 years. Denitrifying enzyme activity (DEA) was measured using the acetylene block assay and terminal restriction length polymorphism profiles were generated with nosZ primers that target the gene coding for nitrous oxide reductase. Nitrate concentrations, C mineralization, and water content were measured to gain additional insights into soil properties controlling DEA. Meadow soils were significantly higher in DEA than forest soils, and the highest DEA levels were observed in cores transferred from the meadow into the forest. Nitrate concentrations were also different between forest and meadow soils, but did not correlate to DEA. DEA was higher in open versus closed cores, suggesting an association between denitrification and the rhizosphere. Denitrifier communities of undisturbed forest and meadow soils shifted through a 4-year period but remained distinct from each other. Similarly, denitrifier communities clustered by vegetation type of origin regardless of manipulation, suggesting that the overall denitrifier communities are well buffered against environmental changes.  相似文献   
97.
Coastal rainforests of southeast Alaska have relatively simple species composition but complex structures with high diversity of tree ages, sizes and forest canopy layers, and an abundant understory plant community. Wildlife and fisheries resources also play an important role in the ecological functioning of forest and aquatic systems. Clearcutting has greatly altered these forest ecosystems with significant decreases in structural diversity of forest stands and greatly reduced wildlife habitat. This paper synthesizes information on management options in older forests that have never been actively managed, and in younger forests to increase diversity of stand structures and their associated effects on biodiversity. Light to moderate levels of partial cutting in old-growth forests can maintain the original diversity of overstory stand structures and understory plant communities. In younger forests that develop after clearcutting, mixed alder-conifer stands provide more heterogeneous structures and significantly higher understory biomass than in pure conifer forests. Research has shown that red alder increases diversity and abundance of understory plants, and provides forage for deer and small mammals. Results also show a clear linkage between alder and improved invertebrate diversity in aquatic systems. A combination of light partial cutting in older forests along with inclusion of red alder in conifer-dominated forests could provide the greatest amount of diversity and maintain the complex stand structures that are an important component of these forest ecosystems.  相似文献   
98.
对上海市郊外环林带两侧总悬浮颗粒物浓度(简称TSP)和可吸入颗粒物浓度(简称PM10)同步测定表明:林带的防尘效应与风向有关,下风向处的TSP与PM10日均浓度均分别比上风向低19%-44%和39%-61%。林带边粒径分布测定结果表明:下风向处较大粒径颗粒物的相对含量比上风向处小一些;冬季的粒子谱分布呈现较大粒子和较小粒子重量累积百分比较高、中等粒子的重量累积百分比较低的态势;而春季则相反,中等粒子的重量累积百分比较高、较大粒子和较小粒子则比较低。说明冬春不同风向条件下上海市郊的大道旁林带区具有一定的防尘效应。  相似文献   
99.
以庄浪县5种林草间作模式为对象,在田间采用张力计法测定各模式地的低吸力段土壤水分特征曲线,分析各模式地的土壤持水性能,比较不同模式地的比水容量,结果表明,各模式地土壤含水率随吸力变化较快;五种模式不同土层土壤持水力存在明显差异,表层土壤持水力较大,60cm土层土壤持水能力最差。仁用杏+红豆草模式地土壤持水能力和供水能力最强,是最为耐旱模式,油松+紫花苜蓿模式供水能力最差。  相似文献   
100.
天保工程建设是生态环境建设的重要措施,是人与自然和谐发展的重要基础。我们对鹤峰实施天保工程以后,森林资源变化情况、水土流失变化情况等重要生态环境因子进行了详细调查,并与天保工程实施前比较,结果表明:5年来,鹤峰县天保工程建设取得了阶段性成效,生态、经济、社会三大效益显著,折算总效益784 959.90万元。  相似文献   
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