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森林生态系统服务功能是指森林生态系统与生态过程所形成及所维持人类赖以生存的自然环境条件与效用。它支撑和维护了地球的生命保障系统、生命物质的地化循环与水文循环、生物多样性、大气化学成分的平衡与稳定。文章根据当前国内外森林生态系统生态服务功能与价值研究现状,选用森林的涵养水源、保育土壤、固碳释氧、养分物质贮存、净化大气、生物物种保育、森林游憩等7大类指标,对阿尔山森林生态系统生态服务功能价值进行评估。 相似文献
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加强森林生物多样性的保护,对保护生物多样性具有十分重要的作用。四川地处我国西南林区的主体部份,森林资源丰厚,森林生态系统复杂,使森林生物在物种、生态系统和遗传信息等三个层次上具有丰富度与多样性。为适应我国生物多样性的保护形势及要求,对四川的森林生物多样性保护工作从八个方面探讨其策略。 相似文献
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黑龙江黑河森林生态定位观测研究站是中国森林生态系统定位观测研究网络(CFERN)中的第91个森林生态站,主要对大小兴安岭过渡区的生物多样性、红松天然分布北界群落特征、火山森林生态系统结构与功能、森林功能对环境质量的影响等进行长期系统的定位观测研究。目的是为揭示过渡区森林生态系统的演替和恢复规律、为量化生态服务功能与生态效益补偿、为森林与人居环境的规划与管理提供理论依据和技术支撑。文章对黑龙江黑河森林生态定位观测研究站建设必要性进行了论述。 相似文献
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森林生态系统的生物多样性保护问题 总被引：3，自引：0，他引：3
生物多样性的保护和可持续的利用对森林的保护与可持续经营具有特别重要的意义，生物多样性保护在森林生态系统管理中也越来越显示其重要性。讨论全球森林生态系统生物多样性保护的发展趋势及森林生态系统生物多样性保护的理论和对策，以及生物多样性指数在评价生物多样性管理的应用，提出我国生物多样性保护研究应该加强的方向。 相似文献
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加强森林生物多样性的保护，对保护生物多样性具有十分重要的作用。四川地处我国西南林区的主体部分，森林资源丰厚，森林生态系统复杂，使森林生物在物种、生态系统和跗信息等三个层次上具有丰富度与多样性。为适应我国生物多样性的保护形势及要求，对四川的森林生物多样性保护工作从八个方面探讨其策略。 相似文献
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森林是陆地生态系统中生物多样性最丰富的生态系统。森林生物多样性对于维持陆地生态系统平衡,保证人类生存和社会经济可持续发展起着不可替代的重要作用。对森林生物多样性进行评估、监测和报告是有效保护生物多样性、合理利用其资源、保证其可持续发展的基础和关键。建立一个有效的生物多样性评价指标体系是对生物多样性正确评估的前提和基础,而合适的指标的筛选是构建这一体系的首要工作。本文从文献分析的角度,分析了生物多样性的评价方法,提出了森林生物多样性评价指标的选择原则以及其中需要注意的一些问题,提出了基于林分水平上的生物多样性评价指标的初步构想,为全面构建森林生物多样性评价指标体系奠定理论基础。 相似文献
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《辽宁林业科技》2015,(1)
本研究基于退耕还林工程生态效益专项监测站和中国森林生态系统定位研究网络所属森林生态站等的数据资源,参照《退耕还林工程生态效益监测评估技术标准与管理规范》(办退字[2013]16号)和《森林生态系统服务功能评估规范》(LY/T 1721-2008),应用分布式测算方法评估了辽宁省退耕还林工程的生态效益。结果显示全省退耕还林工程每年生态效益总价值量为491.94亿元;朝阳市、大连市、葫芦岛市生态效益总价值量位于全省前3位;辽中平原地区的辽阳市、营口市、盘锦市生态效益总价值量位于全省后3位。涵养水源和生物多样性保护为主导生态功能,生态效益价值量分别占总价值量的26.84%和26.30%。不同林种类型生态效益各分项价值量均为生态林(372.9亿元)最大,经济林(98.1亿元)次之,灌木林(20.94亿元)最小。 相似文献
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通过近年来的调查和从相关部门收集的资料，结合本地气候、土壤、地形地貌、水文等自然环境，从生物多样性、森林生态系统、湿地资源、自然保护区建设、生态建设及水土保持等方面分析了襄阳市生态环境质量现状，并提出了相应的对策。 相似文献
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《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
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《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
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《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
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《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
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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
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《Scandinavian Journal of Forest Research》2012,27(2):131-138
The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(5):472-479
Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken. 相似文献
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Srisuda Thippayarugs Banyong Toomsan Patma Vityakon Viriya Limpinuntana Aran Patanothai Georg Cadisch 《Agroforestry Systems》2008,72(2):137-148
In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic
or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts
(stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea
(Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content
as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest
N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized
to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea,
largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for
N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant
components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N
released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures
were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality
components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in
the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols.
Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest
age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its
components are mixed. 相似文献
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A. Rigueiro-Rodríguez M. R. Mosquera-Losada E. Gatica-Trabanini 《Agroforestry Systems》2000,48(3):245-256
The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste
disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization,
(2) milk sewage sludge at 40 kg N ha−1 target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two
pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha−1. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1); (2) Lolium perenne L. var. Tove (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea
(Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m2, with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect
on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage
sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but
affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral
systems.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献