太原市居住区绿地植物应用与配置模式研究

以太原市绿化达标的40个居住区为研究对象,将居住区绿地分为公共绿地、宅旁绿地、道路绿地和配套公建绿地4类,对居住区内植物种类、植物配置、植物空间效果进行调查,总结归纳了植物组成与主要节点植物空间特征;采用层次分析法(AHP)构建太原市居住区植物配置适宜性与景观效果评价体系,并对45种植物配置模式进行评价。结果表明:太原市居住区绿地适用植物共有356种,绿地植物景观节点类型10类,绿地植物配置综合评价总体得分值较高,结合综合评价结果得出10种典型植物配置模式。     

城市森林不同类型绿地植物配置抑菌效应初析

江苏省淮安市城市森林不类型绿地植物配置的抑菌效应测定结果表明,无论春、夏、冬季各样地绿化配置树种、植物均有明显抑菌功能,且抑菌效果存在明显的差异。研究结果为城市森林绿地生态保健型绿化模式构建提供了科学依据。       

宁波城市园林植物多样性调查研究

对宁波城市公共绿地居住区绿地、单位附属绿地、通道绿地等4类绿地进行了园林植物多样性调查。结果表明,宁波城市现有园林植物82科175属356种。植物种类在不同绿地上的水平空间分布格局为:公共绿地(274种)>单位附属绿地(202种)>居住区绿地(122种)>通道绿地(105种);从植物的垂直空间分布上看,乔灌木层植物具有较高的种类组成,而地被层的物种组成成分较低。植物群落配置以乔—灌—草结构为主(占73%),乡土植物种数仅占各种园林植物总数的26.9%。植物多样性综合评价指标排序为:通道绿地>公共绿地>居住区绿地>单位附属绿地,与物种丰富度Patrick指数(S)和Margalef指数(da)的排序完全一致。     

季风常绿阔叶林不同恢复阶段附生维管植物多样性及分布

通过对云南普洱地区不同恢复阶段(恢复15年、30年和原始林群落)季风常绿阔叶林群落内附生维管植物的调查,分析了不同恢复阶段附生维管植物的物种丰富度、多度、分布和相似性关系,并探讨附生维管植物与宿主的关系。结果表明:(1)在0.81 hm²的调查样地中,共发现附生维管植物3 116株(分属9科20属22种);(2)原始林中附生维管植物的物种丰富度(17种)要显著高于恢复30年(7种)和15年(5种)群落;(3)原始林与不同恢复阶段群落中附生维管植物的物种组成有显著不同,恢复15年群落中的附生植物主要由蕨类植物组成,兰科植物是原始林附生植物的主要物种组成,有些物种仅出现在原始林中,可以作为季风常绿阔叶林恢复程度的指示物种;(4)原始林附生维管植物的多度要显著高于恢复阶段;(5)3个群落类型中的附生维管植物在水平方向都为聚集分布,恢复15年群落主要分布在0~5 m,原始林中分布可达到20 m;(6)原始林中附生维管植物物种丰富度和多度与宿主的胸径之间存在显著正相关,而2个恢复阶段森林中不存在相关性。     

青神县城市森林结构特征

森林的结构决定功能,功能反映结构。调查青神县城市森林结构现状,分析存在的问题和空间规律,为森林城市的规划和城市森林的建设提供基础资料和参考依据。将青城县城区的绿地分为公园绿地、道路防护绿地和附属绿地三大类。对这三大类绿地内的木本植物进行全部或抽样调查。分析物种组成特征,计算物种多样性、径级结构和冠幅结构等。结果:(1)青神县城市森林的木本植物一共有96种(不含竹林湿地公园),隶属于45科76属。(2)城市森林绿化木本植物中常绿植物明显占优势,常绿植物物种数是落叶物种数的1.88倍。(3)物种多样性水平以附属绿地最高,其次是公园绿地,街道防护绿地最低。(4)从观赏部位来看,以植株造型和观花物种占优势,分别占总物种数的36.73%、29.59%,色叶类物种数占13.27%。(5)乔木物种以胸径10～20 cm、冠幅2～4 m的最多,均占50%以上。青神县城市森林物种多样性还不够丰富,在今后的城市森林建设中,应以乡土乔木树种为主,合理搭配灌、草物种,并增加色叶、观花、观果类植物的种类和数量。     

居住小区植物配置方式对大气颗粒物浓度的影响

为了探讨有效调控颗粒物的居住小区植物配置方式,将居住区绿地按照位置和功能划分为小区入口绿地、道路绿地和广场绿地3种类型,针对每种类型的绿地探讨了不同植物配置方式对于大气颗粒物浓度的削减效应。结果显示:乔木数量较多且通风良好的小区绿地对居住区内颗粒物削减率较高;悬铃木(Platanus orientalis)搭配大叶黄杨(Euonymus japonicus)作为行道树对大气颗粒物的净化能力较强,对TSP、PM_(10)和PM_(2.5)的削减率分别达18.87%、6.40%和6.02%;与开放式广场绿地和中心绿地相比,合理配置的半封闭式广场绿地能够更加有效地改善活动空间的空气质量。     

长春市典型城市森林景观秋季美学特征分析与评价

通过美景度评价法(SBE)对长春市典型城市森林景观秋季美学质量进行了科学与系统的分析与评价,将长春市城市森林景观要素与美景度间建立了关系,对影响长春市城市森林群落秋季景观美学特征的因素进行了筛选和提取,在以上分析结果基础上将长春市城市森林景观进行了分类,结果表明:平均冠幅、灌木高度等级、灌木盖度等级、林分密度等级与林分郁闭度等级为影响长春市秋季城市森林景观综合美景度的主导因素。群落乔木树种多样性、乔木生长状况、灌木分布、植物景观密度与群落结构确定为影响长春市秋季城市森林景观的主要因子。并将长春市秋季城市森林景观分为3类,分别为:(1)以郁闭度较低,有阔叶树种,乔木较多,且灌木较少的公园绿地为主的城市森林景观;(2)以针阔混交类型绿地为主,且灌木高度与盖度较大的城市森林景观;(3)多为乔灌草复层结构,并以落叶阔叶林分或针阔混交林分为主,且灌木较多的城市森林景观。由此可见,植物种的合理搭配、密度控制与树种选择,能够改善林分质量、林分层次与景观色彩,是提高城市森林景观质量的重要措施。     

重庆主城区边坡绿地植物群落的结构分析

以重庆主城区边坡绿地为研究对象,调查分析了边坡绿地物种组成、配置模式、乔木层亚层数及外貌特征。结果表明:在调查范围内,边坡绿地共有植物83种,群落中最多有16种植物,具有4种植物的群落比例最大(27.27%);有9种配置模式,"灌+草"型的群落最多(25.00%);有75.00%的群落无乔木层结构或仅有单层乔木层结构;乔木层常绿与落叶树种的种类和数量比例分别为1∶2.57、1∶2.09。     

扬州古运河生态林地植物配置及环境效应研究

对扬州古运河生态林地不同种植结构类型的典型配置模式进行试验分析可知:绿地遮光效应的大小主要是由植物种类、生长状态及空间配置方式等综合因素决定;与种植结构关系应视具体情况而定;蒸腾作用强且绿量大的植物构成配置模式的降温效果优于其它模式。绿地主要植物种类相同,复层林配置模式的降温效果优于单层林;不同植物的绿量、树形、树冠大小等结构特征不同;植物蒸腾作用能力是影响绿地增湿效应的重要因素;绿地CO2吸收率的大小与植物种类密切相关,且由植物光合作用能力与植株的三维绿量共同决定。     

郑州城市园林植物群落物种多样性研究

采用典型抽样法,对郑州城市园林植物群落的种类组成和物种多样性进行了调查统计和分析。结果表明:1)3种不同类型绿地植物种类共计186种,隶属于72科133属;2)公园绿地的乔木层、灌木层和草本层物种α多样性指数均高于居住区绿地和道路绿地;3)公园绿地的β多样性指数均高于居住区绿地和道路绿地,居住区绿地和道路绿地之间的β多样性指数较小。针对郑州城市园林植物群落物种多样性的实际调查情况,提出加大乡土植物的运用,注意丰富季相景观和植物群落垂直结构层次的建议。     

森林珠海发展的理论与路径探讨

森林珠海是以珠海"城、山、江、田、海、岛"的生态格局为依托,以城市森林工程为手段,构建以森林植被为主体的、森林和园林和谐统一的城市森林生态网络和城市森林绿化网络。文中介绍珠海森林城市建设现状与存在的问题,以科学发展观、城市生态系统学、森林生态学和"近自然"森林群落理论作为森林珠海发展的理论基础,对森林珠海如何发展提出具体路径:确立五大目标,构建三大体系,划分三大功能区,实施十大重点工程。     

Woody plant species diversity and composition in and around Debre Libanos church forests of North Shoa Zone of Oromiya,Ethiopia

Dry afromontane forests are among the most poorly managed and endangered ecosystems.Therefore,we assessed the composition,diversity,and conservation status of woody plant species of the Debre Libanos church forests and surrounding forest lands in Oromiya Regional National State,central Ethiopia in 62 nested circular sample plots spaced 200 m apart along two transect lines.Large circular plots 314 m~2 were used to sample trees with DBH of at least 10 cm,and subplots of 28.26 m~2 were laid in each main plot were used to assess saplings and shrubs;a small subplot of 3.14 m~2 was used to assess seedlings.In total,70 woody plant species belonging to 62 genera and 43 families were recorded.Of these,59,28 and 32 were in the church,government and private forest types,respectively.The most dominant families were Fabaceae and Verbenaceae,each represented by five species.In the forests considered,trees accounted for 61%,and shrubs with diameter at breast height(DBH) of 1-10 cm accounted for ca.33%.Among growth forms of woody species,shrubs and seedlings,followed by trees constituted much of the density of woody species in all the three ownership types of forests.The church forest had the most species(59) and highest Shannon(3.12) and Simpson(0.92) species diversity indices,and the government and private forests had a nearly similar total number of species and Shannon and Simpson species diversity indices.Most of the species with higher importance value indices(IVI) were indigenous in origin within the church forest(Juniperus procera=82),government forest(J.procera=66) and private forest(Acacia abyssinica=84).The composition,diversity,and population structure of woody species in the church forest were significantly higher than in the other forest lands.However,interventions of the government and private sectors to conserve forest systems in the areas,particularly the government-owned forest and specific species such as Olea europaea need active enrichment plantings due to their limited natural regeneration.Without improved management interventions,livelihood income diversification and ecosystem services obtained from the forest will not be sustainable.     

Understory diversity and composition after planting of teak and mahogany in Yogyakarta,Indonesia

ABSTRACT

Forest rehabilitation is when a desired tree species is planted in degraded forests or lands. Rehabilitation by planting a single tree species is a common way to restore exploited forests to maintain ecological processes. We compared woody and herbaceous understory vegetation between forests rehabilitated by mahogany (N = 12) or teak (N = 12) planted from 1941 until 2003 in Yogyakarta, Indonesia. Understory vegetation of these areas was compared with that of three native forests. Species richness, species diversity, density of plants and proportion of native plants did not differ between the rehabilitated areas and the native forest. Recently rehabilitated areas were different from the native forests while 41–74 yr after rehabilitation, characteristics of understory vegetation approached those of native forest. We described species composition using ordination, and found it to differ between areas rehabilitated with teak and with mahogany and, particularly, between the rehabilitated areas and the native forests. Time since rehabilitation and tree species planted were important for the species composition of understory vegetation. We conclude that the selection of species for rehabilitation and letting rehabilitated areas mature are important for understory development and species diversity.     

Effects of multiple factors on plant diversity of forest fragments in intensive farmland of Northern Portugal

The joint and independent effects of dominant tree species, forest patch spatial attributes, and forest structure and management as drivers of plant species richness and composition in small forest patches scattered within an intensive agricultural landscape were addressed.In a landscape with scattered urban and intensive dairy agricultural areas in north-west Portugal, within which small forest patches (dominated by pines, eucalypts, or both) represent semi-natural habitat islands, 50 small forest patches, with areas ranging between 0.3 and 3 ha, were selected and surveyed for vascular plant diversity, within dairy farming landscape mosaics dominated by annual forage crops. Explanatory variables were composed of three datasets derived either from GIS mapping or field observations: forest type (dominant tree species), forest patch spatial attributes (patch area and shape index), and measures of forest management and structure (diameter at breast height, tree density per hectare, and percentage cover of vegetation strata). Variations in these forest patch attributes were assessed across forest types, and related to measures of plant diversity (total, native, alien, woody, and herbaceous species richness). Redundancy analysis with variance partitioning was applied to evaluate the joint and independent effects of the three sets of variables on species assemblages. The recent shift in canopy dominance from pine to eucalypt observed in the region appears to be related to a (nonsignificant) tendency for the increase of patch area and to the decrease of patch complexity, as well as several changes in forest structure and management, expressed as a trend to denser tree canopies and lower cover of understory plants. Dominant tree species and attributes related to forest structure and management were the most important factors determining plant diversity. The joint effect of the dominant tree species and forest structure and management resulted in lower levels of plant species richness in eucalypt plantations. These were also more prone to invasion by alien species, probably due to decreased biotic resistance from unsaturated native plant assemblages. Our results draw attention to the importance of dominant tree species and management practices for the maintenance of plant diversity levels (species richness and composition) in dairy landscape mosaics, highlighting the importance of the remnants of semi-natural forests as refuges for plant diversity in the landscape context. Nonetheless, forest plant diversity could further be fostered by promoting naturalness of pine stands and the regeneration of native oak woodlands in some forest areas. This would also diversify the range of ecosystem services that could be provided by forest areas in these peri-urban farmlands.     

珠海市山地森林及其植物多样性研究

珠海市是广东省最早建立的经济特区之一。由于长期的人类活动,珠海市原生森林早已破坏殆尽,现有的山地森林群落多为人工林和次生植被。应用样方法,在珠海面积较大、林相结构较完整的森林群落中设置了34个面积400m2的样方,调查和分析了这些山地森林群落的物种组成和植物多样性特点。研究结果表明,珠海市山地森林群落类型主要有风水林、沟谷林和早期次生林,以风水林和沟谷林的物种多样性较高,它们是珠海市宝贵的森林遗产。珠海市的森林群落以樟科、大戟科和山茶科植物最为丰富,茜草科、桃金娘科和桑科等热带植物种类也比较丰富。珠海市的天然林对维持当地生态平衡和区域性生物多样性的保护均具有重要的作用。     

Factors influencing the formation of unburned forest islands within the perimeter of a large forest fire

Large forest fires have recently increased in frequency and severity in many ecosystems. Due to the heterogeneity in fuels, weather and topography, these large fires tend to form unburned islands of vegetation. This study focuses on a large forest fire that occurred in north-eastern Spain in 1998, which left large areas of unburned vegetation within its perimeter. Based on a satellite post-fire severity map we searched for the relative influence of biotic and abiotic factors leading to unburned island formation. We divided the area of the fire into individual units we called “slopes” which were meant to separate the differential microclimatic effects of contrasted aspects. The number of unburned islands and their areas were related to 12 variables that influence their formation (i.e. land cover composition, aspect, steepness, forest structure, two landscape indices and weather variables). We hypothesized that unburned vegetation islands would concentrate on northern aspects, in less flammable forests (i.e. broadleaf species) and higher fragmentation to interrupt the advance of fire. While north and western aspects did have a higher presence of unburned vegetation islands, our study suggests greater presence of islands in slopes that are larger (i.e. more continuous areas with relatively homogeneous aspect), with greater proportions of forest cover, with higher wood volumes and with lower proportions of broadleaf species. Climate also played a role, with relative humidity and wind speed positively and negatively correlated to island formation, respectively. Unburned vegetation was more frequent on slopes with lower diversity of land covers and higher dominance of one land cover in the slope. Since slopes with only one land cover (i.e. forests) had more islands than slopes with multiple cover types, we infer that under severe meteorological conditions, fragmented forests can be more affected by wind and by water stress, thus burning more readily than forests that are protected from this edge phenomenon. These results would reinforce forest management strategies that avoid linear features (fire-lines and fire-breaks), to enhance fuel treatments that focus on areas and minimize fragmentation.     

深圳市立交绿地植物多样性及其叶面积指数研究

对深圳市部分立交绿地植物群落的物种丰富度指数、多样性指数、均匀度指数、群落林冠孔隙度和群落叶面积指数进行了比较分析。结果表明,深圳市立交绿地的植物物种丰富,但分布不均匀,多样性不够高;平均叶面积指数为3.05,属中等水平,但不同的立交绿地由于物种组成及结构的不同,其叶面积指数值有差异;平均林冠孔隙度为14.47,在保护较好的立交绿地具有较丰富的非林冠层乔木种类的幼苗。     

Restoration of dry tropical forests in Central America: A review of pattern and process

Much information on restoration and management exists for wet tropical forests of Central America but comparatively little work has been done in the dry forests of this region. Such information is critical for reforestation efforts that are now occurring throughout Central America. This paper describes processes of degradation due to land use and provides a conceptual framework for the restoration of dry tropical forest. Most of this forest type was initially harvested for timber and then cleared for cattle in the last century (1930-1970). Only 1.7% remains largely restricted to infertile soils and remote areas on the Pacific coastal side of Panama, Costa Rica, Nicaragua and Mexico. These cleared areas are again in a state of transition due to a combination of decreasing land productivity, and land speculation for tourism development. Some farms have been sold to new landowners who are interested in reforesting to increase biodiversity and forest cover. Attempts have therefore been made to reforest by protecting the land from fire and cattle, by supplementing natural regrowth with enrichment planting, or through use of tree plantations. Experimental studies have demonstrated the ability of these lands to grow back to forests because of native species ability to sprout after cutting, and the capacity of remnant trees in field and riparian zones to provide seeds and to moderate edge environment for seed germination and seedling establishment. However, research also shows that on sites with long histories of land clearance, species diversity will remain low with functional groups missing unless some active management occurs. Under-planting with late-successional native tree species can add structure and diversity; enrichment planting with large-fruited shade-intolerant species can initiate new islands of more diverse regeneration beneath their canopies; and plantings of fast-growing, nitrogen-fixing trees that provide light canopy shade can moderate the environment below, promoting regeneration establishment of late-successional species. Plantations are the only option for lands that have lost almost all remnants of native forest, and where soils and vegetation have changed to new states of structure and function. Conversion of pastures to tree plantations that can facilitate natural regeneration beneath them is appropriate when pastures are prone to fire and/or lack immediate seed sources nearby. After the grasses have been shaded out, natural recruitment can slowly occur over a 10-15 years period. Under-planting of shade-tolerant late-successional species can supplement species composition and structure.     

基于GIS和Markov的黄龙山天然林区林地变化研究

以黄龙山林区为研究对象,以其1986年、1997年、2006年森林资源二类调查资料为数据源,运用GIS空间分析模型、土地利用动态度模型对该林区三期林地面积变化及水平空间格局特征进行了分析,并运用马尔可夫(Markov)模型对2015年林地类型分布状况进行了预测。研究表明:研究区林地类型结构以阔叶林和针叶林为主;1986-1997年间,针叶林、阔叶林、农田等面积增加,荒地剧烈减少,反映出该区域天然更新、人工抚育和植树造林以及垦荒造田的发展过程;1997-2006年间,退耕还工程的实施,使农田和荒地减少,阔叶林和灌木林地,特别是针叶林的大幅增加,主要变化趋势为其他土地利用类型转向有林地和灌木林地,土地利用类型向着更加理想的方向转移。Markov模型模拟结果表明,今后9年内阔叶林面积将会由增加转为减少,针叶林面积和针阔混交林面积有所增加,这一结果将在2015年林地变化调查中进行验证。     

Diversity and succession of adventive and indigenous vascular understorey plants in Pinus radiata plantation forests in New Zealand

The vegetation of Pinus radiata plantation forests in New Zealand was studied to examine how the indigenous flora has responded to this novel habitat. A chronosequence of stands about 5, 16 and 27 years was assessed in each of four different biogeographic regions to test the effects of several stand and site factors on the succession of vascular understorey plant communities. A total of 202 indigenous and 70 adventive vascular plant species were found across all study areas, with considerable geographic variation among forests in species composition, species richness (range 48–135 species), and the percentage of indigenous species (50–86%). Both richness and cover of adventive species decreased significantly over time, whereas richness and cover of indigenous species was highest in the oldest stands, and overall species richness was lowest at mid-rotation. The guild composition changed from dominance of grasses and forbs in young stands to dominance of ferns and understorey trees in mature stands. These temporal changes were accompanied by a decrease in light-demanding pioneer species and an increase in shade tolerant, later seral species adapted to a forest environment. Measurements of the degree of canopy closure in stands with low or high stocking and modelling of temporal changes of canopy closure indicated that these understorey plant dynamics are influenced by changes in light availability as stands age. Despite the successional changes within forests, geographic variation more strongly influenced understorey communities because stands within a forest area were grouped together in DCA and TWINSPAN analyses, along rainfall and temperature gradients. Although the canopy species of such intensively managed plantation forests is an alien element in the New Zealand flora, the sheltered forest environment of older stands allows the establishment of a mostly indigenous forest understorey community with considerable similarities to indigenous forests located nearby.