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选取2010—2020年福州市林业、生态环境和经济发展水平数据,构建福州市林业—生态环境—经济系统综合评价指标体系,分析其综合发展水平趋势,并利用耦合协调度模型分析3个子系统的耦合协调发展特征。结果表明,2010—2020年福州市的耦合协调程度由失调向优质协调转换,期间经历了严重失调—中度失调—轻度失调—初级失调—勉强协调—良好协调—优质协调的过程。2010—2020年福州市协调度均低于耦合度,在不同的阶段存在林业滞后、经济滞后以及生态环境滞后等问题。结合研究结果,提出福州市未来林业—经济—生态环境系统的协调可持续发展的相应建议。 相似文献
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在分析南昌市城市绿地动态变化的基础上,对该市2005—2014年绿地生态系统服务功能价值进行评估,并引入生态经济协调度(EEH)指数,分析区域内的生态经济协调发展水平。结果表明:2005—2014年间南昌市绿地生态系统服务功能总价值由506.32×106元增加至1040.40×106元,年增长率为8.33%,每项生态服务价值历年平均价值大小排序为:涵养水源、释氧、固碳、调节气候、保护物种多样性、固定土壤、净化空气;10年间南昌市EEH指数为0.4,处于生态经济低度协调区,经济发展与生态环境基本处于和谐发展。 相似文献
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中国省域森林生态安全与林业产业结构时空耦合测度 总被引：3，自引：1，他引：2
在探讨森林生态安全与林业产业结构耦合特征的基础上,分别构建森林生态安全与林业产业结构评价指标体系,并运用耦合协调度模型对2007,2010,2013,2016年中国大陆各省域森林生态安全与林业产业结构的耦合协调发展关系进行分析。结果表明:从耦合协调发展阶段来看,大部分省域在4个年份分别处于磨合、磨合、磨合、协调阶段,部分省域发展过程出现了跃进或倒退现象;从相对发展状态来看,大部分省域在4个年份分别处于超前、超前、超前、滞后状态,当前森林生态安全较林业产业结构仍存在一定差距;从耦合协调发展类型来看,大部分省域在4个年份分别为类型Ⅵ、Ⅵ、Ⅵ、Ⅶ,当前森林生态安全滞后于林业产业结构,二者处于低度协调阶段。 相似文献
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应用灰色关联分析模型对2005—2012年湖南省湘西州的林业系统的产值结构进行了研究。结果表明,2005—2012年湘西州林业三次产业各产值与其林业总产值的灰色关联度排序为第一产业第三产业第二产业。解释了产生此排序的的原因,同时,结合定性分析方法,分析了湘西州林业产业的现状,指出了湘西州林业产业结构调整存在的问题,并有针对性地提出相应的调整建议,这对于巩固集体林权改革成果,协调湘西州林业生态保护与林业产业发展的关系,以及进一步深化改革有一定的借鉴作用。 相似文献
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基于2003~2016年湘西自治州的相关统计数据,利用灰色关联度模型,全面分析经济与水资源利用效率的交互作用,并构建耦合协调度模型,定量、定性地分析了其水资源利用效率与经济的关联状况以及耦合协调状况,结果表明:(1)湘西自治州水资源利用效率与经济整体关联度系数均在0.5以上,这14年间湘西自治州水资源利用效率与经济的关联性较强;(2)在耦合协调度方面,时间呈波动变化,可分为三个阶段,第一阶段(2003~2005年)耦合协调度波动起伏大,第二阶段(2006~2009年)总体趋势平稳,第三阶段(2010~2016年)呈上升趋势;(3)湘西自治州空间差异明显,古丈县、保靖县处于低水平阶段,泸溪县、花垣县、永顺县、龙山县、凤凰县、吉首市处于拮抗阶段。 相似文献
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土地利用与城市化发展息息相关,若两者处于高度耦合优质协调状态则可促进城市社会经济的可持续发展。以呼包鄂城市群为例,计算了3个城市2001—2016年的土地利用效益与城市化综合指数、耦合协调度和灰色关联度,结果显示:①3个城市的土地利用效益与城市化水平均稳步上升,且呼包鄂土地利用效益平均增幅分别为8.96%、18.01%、24.19%,城市化平均增幅分别为9.45%、8.53%、27.71%,增幅最大的是鄂尔多斯市,包头的平均水平与增长水平都较低;②3个城市均处于高水平耦合阶段,且16a间协调度逐年递增,鄂尔多斯的增长幅度最大,为0.714 3,2009年开始3个城市均进入初级协调状态;③灰色关联度分析结果表明,呼包鄂3个城市的人口密度指标对土地利用效益的影响都是中度相关,分别为0.487 1、0.543 7、0.627 1,人口城市化是对土地利用效益影响最小的因素,所以重视土地利用的方式要远比减少人口数量更能提高土地利用的效率。 相似文献
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呼和浩特市生态环境与经济协调发展综合评价研究 总被引：1，自引：0，他引：1
《内蒙古林业科技》2015,(3)
文章从生态环境与经济发展方面在前人研究的基础上,构建呼和浩特市生态环境与经济协调发展评价指标体系,应用协调发展度评价模型对呼和浩特市2000-2013年生态环境与经济协调发展状况进行定量评价。结果表明:呼和浩特市生态环境与经济协调发展状况总体来说处于相对比较稳定的上升趋势,由2000年严重失调衰退类发展到2001-2003年的中度失调衰退类,到2004-2006年轻度失调衰退类,到2007-2009年和2012年为濒临失调衰退类,到2010-2011年和2013年为勉强协调发展类;但在此期间两者的协调发展类型及其协调发展水平仍然存在差异;2000-2004年、2006-2008年和2010-2011年生态环境与经济协调发展类型均为经济滞后型,2005年、2009年和2012-2013年发展类型为环境滞后型,但两者相差不大。预计未来生态环境与经济会向优质协调方向发展。 相似文献
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《绿色科技》2016,(22)
以贵州省为研究区域,并借助国内外城市化与生态环境耦合关系方面的理论和研究成果,且以2001~2010年贵州省统计年鉴和环境发展公报中的数据为依据,运用变异系数法求各项指标权重,根据权重构建贵州省城市化与生态环境协调发展的综合指标体系,构建了耦合度模型,深入研究了贵州省城市化与生态环境之间的耦合关系。结果表明:2001~2010年以来,贵州省城市化与生态环境发展水平除了在2005~2006年期间有所下降以外,总体来看呈现上升趋势;从耦合协调度来看,贵州省的耦合协调度也在不断增强,从2001年的基本耦合阶段到2010年的高水平耦合阶段。总体来说,贵州省的城市化与生态环境处于相对协调状态,但城市化发展水平一直低于生态环境发展水平,今后必须在进一步保护生态环境的基础上,大力推进城市化发展,这样才能不断促进贵州省城市化与生态环境的协调发展。 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