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1.
根据长岭子湿地公园实际情况,提出以保护优先、突出自然与文化原貌、重视湿地保护教育、旅游设施生态化为原则的生态旅游发展策略及项目规划,旨在为长岭子湿地公园生态旅游合理性开放和湿地资源永续利用提供参考。 相似文献
2.
《中南林业科技大学学报(自然科学版)》2017,(9)
为了评估湖南水府庙国家湿地公园生态旅游环境容量和旅游空间容量,在获得其旅游景点布局与面积、大气环境、水质等方面数据的基础上,对其生态旅游的水质、大气、现有固体废物处置能力和生物(鸟类)等环境容量和旅游空间容量进行了估算。结果表明:其旅游环境日容量为100 000人,旅游空间日容量为30 000~60 000人;现有固体废物处置能力是旅游环境容量的瓶颈,旅游景点面积控制着旅游空间容量;根据木桶原则湖南水府庙国家湿地公园旅游环境容量为每天能容纳游客30 000~60 000人;目前湖南水府庙国家湿地公园生态旅游环境容量和旅游空间容量较大,而旅游设施和旅游服务跟不上,限制了水府庙国家湿地公园旅游产业的发展。因此,必须尽快完善旅游设施,提高旅游管理水平和服务质量,以保障湖南水府庙国家湿地公园生态旅游发展的持续性。 相似文献
3.
在简要介绍城市湿地公园的定义及分类的基础上,重点对汾河景区人工湿地公园野生植物种植区及园林植物种植区2个区域内湿地植物的应用情况进行了介绍,并阐述了湿地植物在湿地公园中的作用,最后提出了湿地植物在发展中存在的问题及以后的研究方向。 相似文献
4.
国家湿地公园建设规范探讨 总被引：10，自引：0，他引：10
目前,湿地公园的建设已经受到各国政府和社会各界的高度重视。我国湿地公园的建设在国家和社会各界的支持下,正在蓬勃发展。到2009年1月,已经建设和获得批准建设的国家级湿地公园达到68个,其中国家湿地公园为38个,国家城市湿地公园30个。但是由于对湿地公园的理解还没有统一的认识,使得我国湿地公园建设在总体布局、规划设计、建设经营等方面缺乏统一的标准。为了使我国湿地公园建设有序、健康地发展,本文对国家湿地公园的定义,国家湿地公园建设的指导思想与基本原则,国家湿地公园建设的目标,国家湿地公园应具备的基本条件、总体布局、规划设计以及主要建设内容等方面进行了探讨。 相似文献
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对湿地生态系统的定义进行了介绍和选取,简述了长株潭湿地资源概况.通过对湿地资源及湿地保护现状的调查分析,以长沙(湘江风光带)湿地公园的建设为例,阐述了长株潭城市近郊湿地的适宜性保护及开发模式--湿地公园,并规划出特色突出、分工明确的人大功能区. 相似文献
7.
根据迎龙湖国家湿地公园的自然生态特点,阐述了湿地公园保护的指导思想、规划原则,并对湿地公园的水系水质、水岸、栖息地(生境)和湿地文化保护等提出了一系列保护工程建设规划,以发挥迎龙湖湿地公园的保护功能,探索了湿地公园保护规划的具体落实内容。 相似文献
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我国湿地公园建设的回顾与展望 总被引：1，自引：0，他引：1
《林业资源管理》2016,(2):39-44
概述了我国湿地公园发展现状和发展历程,对未来我国湿地公园的发展方向进行了判断,指出:湿地公园是今后生态文明建设中自然保护体系的重要组成、生态修复的重要依托和生态教育的重要平台;湿地公园将为我国国家公园体制建设积累经验,部分湿地公园将成为国家公园的重要组成和发展节点;湿地公园将是我国智慧林业的试验田。同时,对我国湿地公园未来发展提出对策建议,即:加强湿地公园体系和综合管理体系建设;实施湿地公园的分类分级管理,强化后期维护和有效管理;严格执行生态红线制度,加强对湿地公园的保护;完善湿地公园的投入、经营管理和公众参与等机制;加强湿地公园相关科学技术研究;加强新技术的应用和新材料的使用;加强湿地公园与社区的合作和协调发展。 相似文献
10.
《中国城市林业》2020,(3)
探明湿地公园价值溢出及其效率的时序演变和内部分异特征,准确把握影响湿地公园建设的关键因素,对确定湿地公园发展方向、提高湿地公园资源配置效率具有重要意义。文章以苏州太湖国家湿地公园为研究对象,采用成本-收益分析法、DEA模型、逐步回归模型等方法对湿地公园2011—2018年价值溢出及其效率进行时序演变、内部分异及影响因素研究。研究结果表明:从时序演变看,在价值溢出方面,生态价值溢出发展平稳,经济价值溢出由快速增长变为负增长,社会价值溢出增速由快转慢;在价值溢出效率方面,生态价值溢出效率由波动上升变为快速下降,经济价值溢出效率缓慢波动上升,社会价值溢出效率长期处于较高水平。从内部分异看,在价值溢出方面一直呈社会生态经济的态势,在不同时期增速略有不同;而价值溢出效率在不同时期呈现不同变化规律。娱乐休闲收益、间接经济收益、景观改造和净化环境是影响太湖国家湿地公园价值溢出的关键因素;生态维护、管理费用、设施费用和广告宣传费用的冗余是限制太湖国家湿地公园价值溢出效率的主要因素。基于研究结果,提出加强生态管护技术输入、提升经济管理和设施成本利用效率及增强科普科研建设的策略期望有助于促进湿地公园价值溢出及其效率提升。 相似文献
11.
《Scandinavian Journal of Forest Research》2012,27(5):427-435
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. 相似文献
12.
《Scandinavian Journal of Forest Research》2012,27(3):206-217
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. 相似文献
13.
《Scandinavian Journal of Forest Research》2012,27(1):53-61
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. 相似文献
14.
《Scandinavian Journal of Forest Research》2012,27(1):15-27
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. 相似文献
15.
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. 相似文献
16.
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。 相似文献
17.
Astra Zaluma Lauma Bruna Darta Klavina Natalija Burnevica Kristine Kenigsvalde Andis Lazdins Talis Gaitnieks 《Forest Pathology》2019,49(6)
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. 相似文献
18.
《Scandinavian Journal of Forest Research》2012,27(2):118-130
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. 相似文献
19.
Steven Maranz Amadou Niang Antoine Kalinganire Djeneba Konaté Bocary Kaya 《Agroforestry Systems》2008,72(3):231-239
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. 相似文献
20.
《Wood material science & engineering》2013,8(2):76-84
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. 相似文献