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51.
《Scandinavian Journal of Forest Research》2012,27(7):668-676
The aim of this study was to investigate to which extent forestry professionals, other “green” professionals (mainly landscape architects) and natural resource students in Denmark agree with the general population regarding their recreational preferences for contrasting stem densities in young, even-aged stands of pedunculate oak (Quercus robur L.). The study was based on five pairs of colour photographs from each of the five recently thinned experimental plots in a 13-year-old stand. The plots represented five different residual stem densities: 7000 (unthinned), 5300 (traditional thinning), 1000, 300 and 100 stems ha?1. All cut trees were left on the ground. The analysis was carried out as a survey of forest and landscape experts (n=158) and the general public (n=243) based on questionnaires. Interviewees ranked the photographs according to the criterion: “Which forest environment do you prefer as a visitor?” Principal component factor analysis showed that the general public tended to perceptually group photos according to similar overall pattern of openness, presence of row structure and stand accessibility (including presence/absence of slash). As long as a stand appeared accessible, stand density had little influence on their preferences for a wide range of stand densities (5300?300 stems ha?1). In contrast, foresters, other “green” professionals and students seemed to perceptually group photos according to treatment type, and the presence of slash had little influence on their preferences. This suggests an influence of professional background, making experts visually analyse and evaluate stands according to contemporary management standards and paradigms within their own profession. 相似文献
52.
解读了盆景与园林同源相生的涵义,认为盆景是把园林景观结合起来的艺术产物,园林是盆景的模本,而盆景又是园林的小样。探讨了盆景与园林的美学思想,解析了盆景和园林的形式美原则,并从主题与立意,布局与构图,变化与统一,主次与均衡,点题与题咏方面,总结了盆景与园林的造景艺术手法。 相似文献
53.
通过分析和评价泾惠渠水利风景旅游区的旅游资源特征及价值,确定旅游区的性质、目标和规划原则,阐述了旅游区的规划布局、功能分区,并提出相关的规划建设建议和措施。 相似文献
54.
乡村林业从它的生产场地和生产内容上看,是当前在中国农村兴起的庭园经济林的同义语,是农村建设的“绿色致富”工程.乡村林业的实施采用立地经营模式,因地制宜,建立商品基地;大力发展产品加工业,提高经济效益;建设好社会化服务体系,推进乡村林业依靠科技进步,向前发展。 相似文献
55.
浅议园林道路的景观设计 总被引:2,自引:0,他引:2
道路在风景园林中起到组织交通、引导游览、分割空间、联系景点和构成园景的多功能作用.从园林道路的线形、材料、色彩、铺装图案和园林道路与山、水、植物、园林小品的布局等多个角度探讨了其景观设计原则. 相似文献
56.
57.
A.M. Prados-Ligero J.L. González-Andújar J.M. Melero-Vara M.J. Basallote-Ureba 《European journal of plant pathology / European Foundation for Plant Pathology》1998,104(9):861-870
Pseudothecia of Pleospora allii developed best on garlic leaf debris infected by Stemphylium vesicarium incubated at low temperature (5–10°C) and relative humidity (RH) close to saturation. RH of less than 96% prevented the formation of pseudothecia, while an incubation temperature of 15–20°C led to the early degeneration of pseudothecia. Under natural conditions, colonization by pseudothecia of unburied garlic leaf debris varied between seasons from 6.0 to 15.5 pseudothecia/mm2, whereas lower colonization levels were recorded when samples were buried. Pseudothecial maturity was reached 1–4mo after the deposition of garlic debris on the soil surface and 15 days after the burial of residues. In the later case, pseudothecia degenerated with degradation of the plant debris. Ascospore release, which required rainfall or dew periods, occurred between late January and late April depending upon the year. A high correlation was found between pseudothecia maturation and four meteorological variables. Two of which, i.e. the number of hours with RH98% and with a mean temperature of 4.5–10.5°C, and the accumulated rainfall, explained most variability (adjusted R2=0.82–0.98 depending upon the year). A multiple regression equation relating the pseudothecia maturity index with these two variables could be used to forecast the epidemic onset of Stemphylium leaf spots in Southern Spain. Temporal progress of pseudothecia maturation was best fitted by a monomolecular model. 相似文献
58.
利用四川竹林资源大力发展园林观赏竹种 总被引:2,自引:0,他引:2
四川竹林资源丰富,除大面积的慈竹、硬头黄竹、毛竹、白夹竹等外,还有多种具有很高观赏价值的竹种。随着森林旅游以及人们要求“回归大自然,返朴归真”,物质文化生活水平的不断提高,挖掘和大力发展园林观赏竹具有十分广阔的前景,会取得显著的社会、生态和经济效益。 相似文献
59.
60.
基于AHP的道路黑点交通安全影响因素分析及应用 总被引:1,自引:1,他引:0
阐述道路黑点交通事故的生成特征,通过AHP法建立交通安全影响因素的层次结构模型,形成了诸因素重要程度量化分析方法,为减少和预防密集型交通事故提供切实依据;应用该方法对某大型交叉口进行了分析和计算,确定了各安全影响因素的权重,提出了相应的安全保障措施。 相似文献