浅析“广场舞”引发的噪声污染问题及对策

指出了近年来,“广场舞”引发的居民矛盾越演越烈,由争吵到泼粪,由鸣枪到刀捅,由广场、公园到火车上、地铁口,由国内到国外,引发众多网民的炒作和广大居民的热议,逐渐成为影响社会稳定的大问题。从“广场舞”问题的提出、如何正确看待“广场舞”、“广场舞”问题是如何产生的、“广场舞”问题的对策建议等几个方面阐述了自己的认识和思考。     

白冠长尾雉保护中的社区影响——以董寨自然保护区为例

以河南董寨国家级自然保护区为主要研究对象,通过访谈和问卷调查等方式,分析了该保护区社区状况及社区居民生产生活现状,探讨了社区活动行为的方式和时间上对白冠长尾雉的可能影响。结果表明:董寨国家级自然保护区内社区居民较多,增长明显,社区居民的生产生活水平低于河南省平均水平;并且,当地社区人为活动在活动方式、活动季节和活动时间上与白冠长尾雉存在一定影响或冲突。从政府对社区经济发展的支持、社区居民活动的规范管理和时间安排、薪柴砍伐和替代能源以及社区宣传教育等方面提出了合理化建议。     

湖北神农架自然遗产地社区参与现状及对策

社区参与意愿以及如何参与,直接影响到自然遗产的保护和开发活动。本文采用分层随机抽样和入户调查的方式,对湖北神农架自然遗产地社区居民的认知程度、参与现状和意愿诉求等3个方面开展了调查和研究。调查发现,受访者对自然遗产保护与开发有较高的认知度,目前社区整体参与程度较高;列入世界遗产后,社区居民在决策管理、商业经营、利益分配、社会保障等方面的意愿和诉求不会产生显著变化。建议从改变居民生活方式、转变社区就业方式、加强宣传教育、完善社区共管机制等方面进一步完善神农架自然遗产地社区的管理和建设。     

浅谈保护与发展共赢的可持续社区发展模式——以滇西北滇金丝猴社区保护地项目为例

以云南省维西县塔城镇托落顶社区开展的滇西北滇金丝猴社区保护地项目为例,从社区参与滇金丝猴栖息地巡护、促进社区发展、开展社区能力建设活动、建立社区保护地等4个方面分析了生物多样性保护和经济、社会发展的可持续社区发展模式。通过开展一系列替代能源、替代生计示范项目,提高了社区居民的生活水平,降低了社区对周边自然资源的依赖,减轻了社区群众的生产生活对保护区造成的压力,提高了社区居民合理持续利用自然资源的意识。     

轿子山国家级自然保护区社区共管研究

采用参与式农村评估方法(PRA)对轿子山自然保护区周边社区进行调查,阐述社区共管所取得的成效,分析周围社区居民生产、生活活动对自然保护区自然资源的威胁,包括生态保护意识弱、传统的资源消耗模式、过度放牧等。从转变资源利用方式、完善机构设置、加强管理、实施生态移民、提高社区居民素质和争取外援、开展合作交流等方面对进一步开展好社区共管进行了探讨。     

基于健康生活理念的老旧社区微空间更新策略探析--以长沙市侯家塘社区红旗片区为例

指出了社区绿地作为居民最贴近的景观,已日渐成为居民的“户外客厅”。随着经济的高速发展,老旧社区逐渐被城市发展所遗忘,面临着社区绿地面积少、荒废空间多、基础设施破坏严重等现状,老旧社区微空间急需激活与重塑。以长沙市侯家塘社区红旗片区作为研究对象,通过实地调研分析社区微空间类型,从建设资源节约型社会方面出发,提高老旧社区的利用价值,促进老旧社区的可持续发展。并着重从健康生活角度探析社区微空间的改造与建设,总结提出了4个更新策略:即开放天台空间、激活闲置场地、创造交流空间和营造健康氛围。以使老旧社区能够满足居民健康生活的需求。     

社区居民参与乡村旅游开发的途径——以大理州漾濞县金牛村为例

阐述社区居民参与的含义及其在乡村旅游开发中的重要作用。社区居民可通过资源产品化、产业多样化、服务专业化等途径参与旅游开发,对旅游社区的发展分担责任、共享成果。以大理州漾濞县金牛村的乡村旅游规划为研究案例,从村级集体产业规划、乡村旅游产业规划、服务专业化以及乡村旅游规划效益等方面进一步阐明乡村旅游开发中社区居民参与的途径及其重要性。     

河北小五台山国家级自然保护区社区问题初探

河北小五台山国家级自然保护区周边社区居民放牧、采摘野菜、猎捕野生动物等行为,严重威胁到保护区的自然资源和自然环境。保护区需采取有效措施制止破坏资源的行为,并且通过为社区居民提供一些公共事业及技术支持,帮助社区加强基础设施建设等提高当地居民的生活水平,缓和社区和保护区的关系,实现保护区和社区的和谐发展。     

山区生态保护对当地社区居民生计影响的研究进展及展望

山区生态保护和农村扶贫是发展中国家重要的政策,山区生态保护对当地社区居民生计的影响是乡村地理学和生态保护学关注的焦点。基于国内外相关文献,本研究从生态保护对当地社区居民生计资本的影响、生态保护对当地社区居民生计策略的影响和生态保护对当地社区居民生计结果的影响等方面对国内外生态保护对社区居民生计的影响进行系统归纳总结。依据目前研究和实践现状,提出生态补偿对社区居民可持续生计的影响过程与机制是未来需要关注的重点问题,应深入探索生态保护区社区居民可持续生计的研究,强化新技术方法在社区居民可持续生计研究中的运用。     

广西国家级自然保护区与周边社区协调发展研究——以十万大山和并岗自然保护区为例

就保护区与社区间的协调发展问题对广西弄岗、十万大山2个国家级自然保护区周边社区居民进行问卷调查．运用SPSS15．0对调查问卷中的11个指标进行因子分析,确定出4个公共因子,即：周边社区居民对保护区生态效益的认识,保护区相关制度与周边社区相互影响,保护区对周边社区发展的经济影响,社区共管．并从这4个方面对2个保护区与社区间的协调发展情况进行分析,找出发展过程中存在的矛盾,藉此提出提高社区居民对保护区的认识水平,解决社区居民在能源需求、经济发展等方面的实际问题,增强社区共管力度等国家级自然保护区与周边社区协调发展对策和建议．     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.     

Effects of Root Freezing on the Physiology and Growth of Picea glauca,Picea mariana and Pinus banksiana Seedlings Under Different Soil Moisture Regimes

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.     

Decomposition and nutrient loss from prunings of different contour hedgerow species in tea plantations in the sloping highlands of Sri Lanka

Contour hedgerows of multipurpose tree species in the sloping tea lands of Sri Lanka are expected to reduce soil erosion and also add significant amounts of plant nutrients to the soil via periodic prunings. The objective of this experiment was to characterize the biomass decomposition pattern and quantify the amount of nutrients added through prunings of six tree species (Calliandra calothyrsus, Senna spectabilis, Euphatorium innulifolium, Flemingia congesta, Gliricidia sepium and Tithonia diversifolia) currently being used in hedgerows associated with tea. Withered leaf and stem prunings (50 g) were enclosed in 2-mm litter bags, placed at 5-cm depth and retrieved after one, three, six, nine and 12 weeks. Loss of initial dry weight, N, P and K was measured. Single exponential decay function adequately described both dry weight and nutrient loss. Tree species differed significantly in their rate of breakdown with decomposition constants (k) varying from 0.0299 to 0.2006 week⁻¹ for leaves and from 0.0225 to 0.0633 week⁻¹ for stems. Gliricidia showed the highest k for leaves with the rest in the following descending order: Senna > Tithonia ≥ Euphatorium > Calliandra > Flemingia. A similar pattern was observed for loss of all nutrients with Calliandra and Flemingia always having lower k values than the rest. Although N immobilization was not observed, immobilization of P and K was observed during the first week of incubation in some species, particularly in stem prunings. Annual biomass of prunings differed significantly between tree species in the following descending order: Calliandra > Senna > Flemingia > Tithonia > Gliricidia > Euphatorium. Calliandra added the greatest amount of nutrients annually to the soil with Euphatorium adding the least. Calliandra prunings provided the annual total K requirement and 49% of the N requirement of mature tea. However, none of the species provided more than 5% of the P requirement. It is concluded that among the tree species tested, Calliandra and Flemingia are the most suitable for contour hedgerows in tea plantations of this agroclimatic region because of their higher soil nutrient enrichment capacity and slower decomposition rates which would minimize leaching losses. This revised version was published online in June 2006 with corrections to the Cover Date.     

Effects of Seed Weight and Seed Type on Early Seedling Growth of Pinus sylvestris under Harsh and Optimal Conditions

The effects of seed weight and seed type on seedling growth of Pinus sylvestris (L.) were studied by seeding individually weighed orchard and stand seed in different mixtures under harsh (direct seeding in field) and optimal (seeding in nursery) conditions. In the nursery experiment an increase in the seed weight from 3 to 7 mg increased the seedling height by 10-27% and total weight by 27-113%, and decreased the height/diameter ratio by 5-6% after 2 yrs. With elimination of seed weight effects, orchard seedlings were 2% taller than stand seedlings in year 2. Without elimination of seed weight effects, orchard seedlings were 7-13% taller. In the field experiment an increase in the seed weight from 3 to 7 mg increased seedling height by 18-65%, stem volume by 81-274% and the number of top-buds by 23-34% in year 5. After elimination of seed weight effects, orchard seedlings were 7-13% taller than stand seedlings and without elimination of seed weight effects 20-21% taller after 5 yrs. Even after elimination of both seed weight and genetic effects orchard seedlings were 3-9% larger than stand seedlings in the field experiment. In conclusion, the influence of seed weight and seed type on growth traits and slenderness is highly significant and the influence seems to be greater in harsh conditions.     

Modelling of adequate pretwist for obtaining straight timber

Abstract

Wood in general and wooden studs in particular are often distorted owing to uneven shrinkage during the drying process in the sawmill. Twist is often the most detrimental of all types of distortion, and it is caused by spiral grain in combination with variations in moisture content. For sawmills, the objective is to produce dried, straight boards, and one method of dealing with boards with excessive spiral grain is to sort them out and then dry them in a pretwisted position to obtain straight boards after drying. A model using the finite element (FE) method for the simulation of drying twist distortions was first calibrated against laboratory experiments in which boards were dried with and without restraints and pretwists. After the calibration, the FE results were compared with industrial test results for boards that were dried without restraints or with restraints with zero pretwist, i.e. straight restraints. The FE model used an elastic–ideally plastic material model to obtain permanent deformations. The calibration was to set the yield stresses so that there was a good match between FE results and results from the laboratory experiments. The comparison between the industrial test results and the FE results showed that the FE model is capable of realistic simulations of drying boards with and without restraints and presumably also pretwists.     

Potential to harness superior nutritional qualities of exotic baobabs if local adaptation can be conferred through grafting

Baobab leaves form an important part of the local diet in Sahel countries and elsewhere in Africa. Existing leaf nutritional data and agroforestry performance information are based solely on Adansonia digitata L., the baobab of continental Africa. The introduction potential of Adansonia species from the center of diversity in Madagascar and from Australia remains untapped. To assess this potential, the mineral contents and B₁ and B₂ vitamin levels of dried baobab leaves were determined for five-year old trees of A. digitata, A. gibbosa (A. Cunn.) Guymer ex D. Baum, A. rubrostipa Jum. & H. Perrier (syn. A. fony Baill.), A. perrieri Capuron and A. za Baill. grown in an introduction trial in Mali. Nutritional data were evaluated against survival and vigor to identify promising germplasm. Leaf vitamin and crude protein contents were highest in the Madagascar species, especially A. rubrostipa (B₁ 88 mg 100 g⁻¹, B₂ 187 mg 100 g⁻¹, protein 20.7% dry weight). However, the local species far outperformed the introductions in survival, tree height, basal diameter and resistance to termites. We suggest grafting as a way of harnessing the vigor of well-adapted local baobab varieties to the superior nutritional profiles of A. rubrostipa and others. Cross-species grafting tests in Adansonia were successful, thus creating new agroforestry possibilities with different scion/rootstock combinations.     

Growth of Phlebiopsis gigantea in wood of seven conifer species

Heterobasidion parviporum and Heterobasidion annosum are widely distributed root‐rot fungi that infect conifers throughout Europe. Infection of conifer stumps by spores of these pathogens can be controlled by treating fresh stumps with a competing non‐pathogenic fungus, Phlebiopsis gigantea. In this study, growth of three Latvian strains of P. gigantea and the biological control agent ‘Rotstop’ strain was evaluated in stem pieces of Norway spruce, Scots pine, lodgepole pine, Douglas‐fir, Weymouth pine, Siberian larch and Sitka spruce. The growth rates of one H. parviporum and one H. annosum isolate were also measured in the same stem pieces. The growth rate of P. gigantea varied greatly in wood of different conifer species. It was higher in the three pine species, lower in Norway spruce and lowest in Sitka spruce and Siberian larch, and in Douglas‐fir, this fungus did not grow. The largest area of wood occupied by P. gigantea was in lodgepole pine. Growth of Latvian isolates of P. gigantea in the wood of Pinus and Picea species was comparable to that of the Rotstop isolate. Consequently, stump treatment with local P. gigantea isolates should be recommended. However, our results suggest that Douglas‐fir stump treatment against Heterobasidion by P. gigantea may be ineffective and other stump treatment methods should be considered.     

Stand Structure in Pine,Spruce and Deciduous Forests: A Comparison Between Finnish and Russian Karelia

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.     

Growth and Terminal Bud Formation in Picea abies Seedlings Grown with Alternating Diurnal Temperature and Different Light Qualities

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.     

CAD与建筑设计的关系

本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。