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1.
以云南小黑山自然保护区作为研究区域,利用Fragstats软件和Arcgis软件分析了其一级和二级生态系统的分布和面积变化,选取斑块数、平均板块面积、聚集度、类板块平均面积和景观连接度等5个景观指数来分析景观格局及其变化情况。结果表明,10年间,保护区内的草地生态系统面积增加,耕地减少,并且出现了城镇;保护区内的斑块数增加了36个,平均斑块面积降低了0.548 5hm2,聚集度指数增加了2.751 1,该区域内景观完整性度减少。  相似文献   

2.
文章旨在构建湿地景观评价指标体系,在国家规定的科学价值、整体风貌、科普宣传价值、历史文化价值和美学价值5个一级指标的基础上提出了29个二级指标。利用粗糙集理论,对29个二级指标进行筛选,最终在每个一级指标的基础上筛选出二级指标各3个,分别是科学价值:物种多样性、遗传多样性、科研教学价值;整体风貌:结构复杂性、与周围环境协调性、区位条件;科普宣传价值:宣传范围、宣传场馆、宣传次数;历史文化价值:历史人物、历史事件、文化底蕴;美学价值:幽深度、开阔度、视觉多样性。构成一套较完整的拥有一级指标5个,二级指标15个的湿地景观质量评价指标体系。并对阿蓬江湿地景观进行评价,其最后得分值为8.17,质量等级为优秀。  相似文献   

3.
按照建设项目对森林公园景观影响评价工作要求,建立了景观影响评价指标体系,包括7个一级指标和20个二级指标.二级指标影响程度等级分为较小影响、中度影响、较大影响三级,分别赋予50分、70分、90分的分值.根据评价指标权重表计算了各一级指标分值和景观影响指数,根据景观影响指数得分情况判定了建设项目对景观的影响程度,分为较小...  相似文献   

4.
朱凯  汤辉 《广东园林》2013,(5):32-35
亲社会行为又叫积极的社会行为,具体指人们有益的行为。文章通过阐述幼儿亲社会行为的定义、内涵和国外基于亲社会行为培养的幼儿园户外环境设计,总结出适合我国国情的培养幼儿亲社会行为的幼儿园户外环境营建原则和设计方法。试图以此提高业界对儿童使用场地的重视,从而使幼儿园户外环境的设计朝着培养幼儿健全人格的方向发展。  相似文献   

5.
为更好地实现八英庄林场森林资源的优化配置,以河北省木兰围场国有林场管理局八英庄林场2010年和2015年2期地形图、遥感图像及二类调查数据为基础,运用ArcGIS10.0和Fragstats4.2软件,对砬沿沟流域森林景观变化进行分析。砬沿沟流域按一级景观分类划分,斑块类型共5类,有林地斑块面积由473.95hm~2增加为500.88hm~2,其他斑块面积相对减小;有林地的景观形状指数、散布与并列指数减小,分别由3.008 1、59.106 6降为2.481 6、49.060 4;景观多样性由0.426 9减小为0.233 4,说明各斑块的聚集程度有所增加,各斑块之间的连通性有所提高。砬沿沟流域按二级景观分类划分,在有林地类型中,2010年和2015年斑块类型都为5类,到2015年山杏林斑块消失,新增云杉林斑块;2010至2015年华北落叶松林斑块面积、斑块景观形状指数均增加,山杨林斑块面积、斑块景观形状指数均减小。砬沿沟流域森林景观香农多样性指数由1.602 7降为1.389 2。除去一级景观分类中有林地斑块破碎度减小,其他无论是一级景观分类还是二级景观分类,各斑块破碎度都有不同程度的增加,说明近5a一级、二级斑块在总数上有所增加,并且增加的斑块相对独立,并不连续。  相似文献   

6.
森林景观格局是森林景观生态学研究的核心。本文以林场1∶5万的地形林相图及小班调查数据为基本资料,建立森林景观二级分类体系;利用GIS技术,选取景观要素斑块特征指数(类斑近圆指数、分维数)、景观异质性指数(斑块边缘密度、多样性指数、优势度)、景观要素空间相互关系分析指数(联系度、聚集度),系统地分析了林场的森林景观格局,以期在此基础上实现森林景观的优化配置。  相似文献   

7.
基于森林资源二类调查数据的延庆县森林景观格局分析   总被引:3,自引:0,他引:3  
以北京市延庆县1999年和2004年两期森林资源二类调查数据为基础,在ArcG IS的支持下,使用PatchAnalyst 4软件计算出10个景观指数,对研究区域的森林景观进行了要素组成、斑块特征、异质性和空间分布等的动态分析。结果表明,以土地类型和优势树种为依据的二级森林景观类型为标准,在以有林地为基质的森林景观格局中,由于人工和自然因素影响,其整体森林景观具有极强的异质性,并且有升高的趋势,使得有林地景观具有较高破碎度。同时非林地受人类活动影响严重,不规则斑块形状进一步加剧。通过对优势树种的二级森林景观类型划分,刺槐、杨树、阔叶杂木等先锋树种的斑块,侧柏、油松、落叶松等人工林树种的斑块,桦树、栎类等高海拔次生林树种的斑块都分别表现出与之生态和林学特性相适应的状态。  相似文献   

8.
文章选取浙北41个乡村聚落,运用SBE评价法对乡村道路植物景观开展美景度评价,按照9种道路植物景观要素分析其对14个典型道路植物景观美景度的影响,构建道路植物景观美景度模型。结果表明:影响道路植物景观美景度的景观要素主要为观赏性和整洁度,美景度值随着观赏性和整洁度增加而增加。研究结果可为乡村道路植物景观规划提供参考借鉴。  相似文献   

9.
基于2018年新密市完善林地变更数据,利用ArcGIS10.2软件,按地类和优势树种组两个属性对小班数据进行重分类,利用Python软件从景观类型组成、破碎度、形状和多样性及优势度等方面对新密市景观格局进行统计分析。结果表明:新密市景观格局以有林地为主,耕地和建设用地为辅,多种景观要素镶嵌分布。林地景观破碎化程度高,景观类型较单一。林地景观中,杨树和泡桐景观面积占比最大,核桃景观的破碎度高,栎类、其他软阔和其他硬阔的连通性相对较好,刺槐景观的形状最不规则。非林地景观中,耕地景观面积占比最大,建设用地景观最不规则。提出分区发展、优化景观布局,增加常绿乡土树种,开展宜林地新造林等对策。  相似文献   

10.
幼儿园自然教育有助于引导幼儿爱护自然、尊重生命,关注环境、保护地球,并激发幼儿的探究精神和创新思维。为探讨幼儿园自然教育研究的新思路与方向,文章运用CiteSpace可视化软件对我国近20年(2004—2022年)的幼儿园自然教育研究文献进行计量分析。结果发现:我国幼儿园自然教育研究可以划分为平缓期、发展期和起伏期3个发展阶段;研究内容主要包括意识理念、环境创设、课程建设、活动实施,以及解决策略5个方面,并取得一定成果。根据分析结果提出研究展望:教育目标应坚持以幼儿为本,支持幼儿在自然中游戏;教育价值应加强理论联系实际;教育活动形式应灵活多样化;研究方法应加强实证研究和行动研究。  相似文献   

11.

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.

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.

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.

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.
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   

16.

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   

17.
18.

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   

19.
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   

20.
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   

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