景观格局动态对浑善达克沙地植物物种多样性和功能多样性的影响

景观格局是影响植物物种多样性(PSD)和功能多样性(PFD)变化的重要驱动因素。然而,目前对景观格局动态的作用机制仍然不清楚。浑善达克沙地固定沙丘、半固定沙丘、流动沙丘、丘间低地、湖泊和建设用地镶嵌分布,形成了复杂的景观格局,是揭示这种机制的理想地区。本文对该地区2008–2017年的遥感图像进行处理,对PSD和PFD进行实地调查和分析,采用Spearman相关性分析和广义线性混合模型识别了对PSD和PFD有显著贡献的景观格局指数;采用结构方程模型解析了景观格局动态变化对PSD和PFD的直接和间接效应。结果表明,PSD和PFD均受2–4年前景观格局的影响。PSD主要受形状指数、面积和边缘指数以及聚集指数的重要影响,PFD主要受形状指数和聚集指数的影响。由于环境过滤和扩散限制,欧氏邻近距离指数和分离度指数是描述PFD的良好指标。综上,在世界干旱和半干旱地区土地的景观规划、管理和生物多样性保护过程中,必须考虑景观的动态和演变。     

基于亲和度法测度湖北省植被格局多样性

以植物群系为指标,采用亲和度分析法测度湖北省的植被格局多样性。研究结果表明,湖北省植被格局的镶嵌多样性值（mosaic diversity,m）为4.071,景观复杂,不存在明显的生态梯度。根据平均亲和度（mean affini-ties,MA）,可将湖北省的植被划分为3类：第一类为中心点,位于中心点的植被比较典型和常见,对联结整个景观的各斑块起着关键的作用,包括武汉市、襄阳市、黄冈市和随州市等4个分区;第二类为外点,位于外点的植被较为珍稀,多为当地特有,对构成整个植被格局的独特性和多样性意义重大,包括鹤峰县、利川市和咸丰县等3个分区;第三类为中间点,位于中间点的植被普遍度和稀有度适中,占据了较多的生境空间,是构成整个湖北省植被格局的基础,包括黄石市、荆州市、荆门市、宜昌市等14个分区。将平均相似性值（mean similarity,MS）从中心点到外点排序,结果表明,毗邻地区相似性高,鄂东北、鄂西北、鄂东南以及江汉平原构成了整个植被格局的普遍性,鄂西南则构成其独特性。湖北省植被格局东部和西部差异较大,比较复杂。     

农业景观步甲多样性时间格局及其与景观结构的关系

于2009年5-9月在北京密云县采用陷阱法对玉米地、花生地、果园和林地4种生境中步甲群落进行取样,并采用逐步线性回归分析了景观中优势生境类型——玉米地中步甲群落及其捕食性步甲功能群多样性的季节分布,及其与周围100、250和500 m半径范围内景观格局指数的关系.结果表明:不同生境下,8月步甲群落、捕食性步甲类群的个体数和物种数均达到最大;5月玉米地中步甲群落的物种数与取样点100 m半径范围内的景观连接度呈正相关,8月步甲群落个体数和500 m半径范围内的景观连接度呈负相关;5月玉米地中捕食性步甲群落不论是个体数还是物种数均与取样点100 m半径范围内景观连接度呈正相关,而8月捕食性步甲的物种数则与100 m尺度范围内的半自然生境的类型数呈负相关.可见,景观连接度、半自然生境的类型数对步甲及其中捕食性步甲群落动态的关键季节的多样性状况有显著影响,合理规划农田半自然用地类型组成、增加景观连接度可促进步甲群落多样性保护及其害虫生物控制功能的发挥.     

基于亲和度法测度湖北省植被格局多样性北大核心CSCD

以植物群系为指标,采用亲和度分析法测度湖北省的植被格局多样性。研究结果表明,湖北省植被格局的镶嵌多样性值(mosaic diversity,m)为4.071,景观复杂,不存在明显的生态梯度。根据平均亲和度(mean affini-ties,MA),可将湖北省的植被划分为3类:第一类为中心点,位于中心点的植被比较典型和常见,对联结整个景观的各斑块起着关键的作用,包括武汉市、襄阳市、黄冈市和随州市等4个分区;第二类为外点,位于外点的植被较为珍稀,多为当地特有,对构成整个植被格局的独特性和多样性意义重大,包括鹤峰县、利川市和咸丰县等3个分区;第三类为中间点,位于中间点的植被普遍度和稀有度适中,占据了较多的生境空间,是构成整个湖北省植被格局的基础,包括黄石市、荆州市、荆门市、宜昌市等14个分区。将平均相似性值(mean similarity,MS)从中心点到外点排序,结果表明,毗邻地区相似性高,鄂东北、鄂西北、鄂东南以及江汉平原构成了整个植被格局的普遍性,鄂西南则构成其独特性。湖北省植被格局东部和西部差异较大,比较复杂。     

百山祖自然保护区植物群落beta多样性

本文采用植物群落学的典型样方法,研究了百山祖自然保护区森林植物群落beta多样性格局及其维持机制。通过对45个20m?20m标准样地的调查数据进行分析,运用Chao’s群落距离指数衡量该植物群落beta多样性格局,并通过Mantel检验、基于距离矩阵的偏RDA分析和方差分解等方法初步检验和衡量了各环境因子差异（包括群落郁闭度、海拔、坡度、坡向和坡位）和群落空间距离对该区域beta多样性格局的影响。结果显示,该区域内植物群落beta多样性随着群落间综合环境差异或群落空间距离的增加而增大, 但环境差异和群落空间距离只能解释36%左右的beta多样性格局。检验的5个环境因子中,只有群落郁闭度和海拔对百山祖自然保护区植物群落beta多样性有显著影响,并且群落郁闭度对beta多样性的解释度（20.0%）略高于海拔对beta多样性的解释度（18.0%）。群落空间距离对百山祖自然保护区beta多样性的解释度最小（9.0%）。本文展现了百山祖自然保护区内植物群落beta多样性格局及其与群落环境和空间距离的关系,所获得的结果支持生境异质性和扩散限制联合对植物群落beta多样性起作用的假说。     

碱化草地景观动态及其对气候变化的响应与多样性和空间格局的关系

试图通过对碱化草地景观动态过程与群落多样性和空间格局的关系的分析,探讨利用景观的多样性指标和空间格局指数来解释和预测景观发展动态及其对气候变化的响应的可能性。运用空间仿真的方法,对东北松嫩平原碱化草地景观动态进行了模拟。模型强调景观内的斑块（即空间匀质生态系统）的演替与土壤碱化度的相互耦合作用。在当前气候条件下,模型的输出结果与观测到的１９８９￣１９９３年在１ｈｍ＾２样地内的斑块分布动态非常吻合。     

黑龙江省森林景观多样性动态

讨论了1949—1981年黑龙江省森林景观多样性的动态。利用1949年和1981年森林资源分布图,选取7个有代表性的度量景观多样性的定量指标：斑块密度、周长-面积分数维、聚集度、斑块散布与毗连指数、Shannon多样性指数、优势度、均匀度,在ESRI’S ARCGIS 8和FRAGSTATS 3．3软件支持下,系统研究了景观元素空间格局的变化。结果表明在近32年的时间进程中,区域森林景观破碎化现象加剧,其中以红松(Pinus koraiensis)林的破碎化最为严重。从斑块多样性、格局多样性和类型多样性的动态变化分析看出,原生的景观斑块类型在数量上不断减少或被异类景观所代替,即景观类型所占景观表面的百分比发生了变化,从而引起景观内部空间格局的改变。整个森林的景观多样性和景观类型分布的均匀性降低,优势度增加。人类不合理的经济活动,如毁林开荒、乱砍滥伐等,改变了景观异质性,从而造成景观多样性的变化。现在应该把对森林的保护和经营提到日程上来。天然林保护工程的实施对于促进林业部门休养生息、培育与保护森林资源,保护生物多样性和改善生态环境等具有重要意义。保护现有森林资源,实行采育结合,实施天然林保护工程,使森林的经营走可持续发展的道路是切实可行的解决办法．     

景观多样性分析及其制图研究

景观多样性是生物多样性研究的主要内容之一。景观多样性是指景观结构、功能和动态的多样性和复杂性。本文讨论了景观多样性的概念、测度和空间制图。提出了景观多样性包括类型多样性、格局多样性和斑块多样性。景观多样性可用多样性指数、优势度、相对丰富度、修改的分维数等指数来测定。一个多样性指数Ｄ＿ｉ＝（ｉ－１）／（ｍ－１）×１００％被给出用于景观多样性制图,黄土高原泉家沟流域被选为研究区域。在地理信息系统的支持下,通过时栅格化的土地利用类型图进行分析操作产生出了研究区域的景观多样性图。对景观多样性进行空间制图有助于分析景观生态过程,研究结果可直接用于景观和土地利用规划、野生动植物保护及立地分析。     

洪河自然保护区典型湿地植物群落组成及物种多样性梯度变化

以洪河自然保护区两类典型湿地——河漫滩湿地与碟形洼地湿地的植物群落为研究对象,探讨其物种组成及物种多样性的梯度变化规律。结果表明,由沼泽至岛状林的梯度上:(1)各群落建群种、优势种和伴生种的种类及其优势度,地表覆盖藓类等组成特征均变化明显;(2)群落的物种丰富度呈逐渐增加格局,丰富度指数分别为26、41、51、68和82;(3)群落的α多样性的变化格局与丰富度格局不太一致,Shannon-Wiener多样性与Pielou均匀度的变化格局基本一致,呈不规则"N"型格局,Simpson优势度的变化格局正好与它们相反,呈不规则倒"N"型格局;上述格局的两个"拐点"出现在沼泽化草甸群落和湿草甸群落中;(4)群落的β多样性——相异性系数和Cody指数均呈先降后升的格局,二者的最小值出现在沼泽化草甸群落和湿草甸群落之间,最大值出现在灌丛草甸和岛状林群落之间;研究认为,典型湿地植物群落物种组成和物种丰富度的梯度变化主要于生境的变化有关,α多样性的变化格局主要与生境的变化和优势种的生物学特性有关,β多样性的格局的原因比较复杂,尚需进一步探讨。     

武汉地区油菜和蚕豆田内蜘蛛群落多样性的初步分析

用五种多样性指数及均匀度指数对武汉市油菜和蚕豆田内蜘蛛群落进行了比较,讨论了多样性指数的生态学意义及其判别力,探讨了其物种多样性值的行为变化,分析测定了油菜及蚕豆田内蜘蛛群落多样性的时间格局。并讨论了群落多样性与丰盛度、均匀度及其与群落稳定性的关系。结果表明:采用Shannon—Weaver指数较为合适。     

Affinities and high-order diversity within landscape mosaics

Summary Concepts and methods for use in the study of plant community variation across a single landscape, or for the comparative analysis of two or more landscapes, are presented. The method is called affinity analysis because it produces a sorting and scaling of all the communities in a data set according to degree of differentiation in composition away from an objectively identified subset of modal communities. Modal communities possess maximum affinity with the whole landscape because they contain a large number of the species common throughout the landscape. The modal communities provide a kind of central tendency for the landscape and an anchor for depicting the dispersion of all other communities in it.To accomplish affinity analysis, the Jaccard similarity coefficient and the WilcoxonT statistic are used in a two-step transformation of the primary species-by-site data matrix. From these calculations we obtain both a visual image, theS-T graph, and summary statistics for the landscape-wide diversity described by the data. One summary statistic is a high-order diversity measure for the total patchwork of communities. We refer to this measure as mosaic diversity. The analytical results are referred to collectively as the metastructure because they provide a general, abstract, characterization of any set of community data. This abstract rendering of the data allows comparison of pattern and variation between taxonomically, geographically, and temporally different landscapes. Either presence/absence or abundance data may be used.Examples using artificial and field data are presented. All but one of the field data sets showed a significantly higher mosaic diversity than would be expected from a randomly constructed landscape. We also show how the new methods may be used with ordination to explore intralandscape patterns in more detail than was previously possible.In addition to statistical matters, ecological and evoutionary interpretations of affinity analysis are discussed. Topics included in this discussion involve reasoning about the influences on diversity arising from micro- and macroevolution, species packing and association, environmental gradients, differential fitness expression among species-populations, continuity in community variation, and the uses of both presence/absence and abundance data in community studies. Among the examples provided, mosaic diversity is independent of diversity (Whittaker, 1972).     

Diversity patterns in grasslands along a landscape gradient in northwestern France

Abstract. Several measures of biodiversity were calculated (species richness SR, species diversity H', species evenness J', mean similarity, mosaic diversity and factorial diversity) in vascular plant communities along a landscape gradient in the Seine valley, Normandy, France. For these communities, we also recorded environmental and management data. Species and environmental data were analysed simultaneously by Canonical Correspondence Analysis (CCA) in order to study their relationships. CCA identifies one main landscape gradient linked to a set of highly linked ecological factors. Three community types were identified along this gradient: calcicolous communities on chalk slopes, mesophilous communities on colluvium and hydrophilous communities on alluviums. The measures of biodiversity between these groups and their variations along the landscape gradient indicate similar patterns for H', J' and SR. Between‐community biodiversity measures allow consideration of the distribution of species among communities in the landscape. Factorial diversity accounts for the organisation of the communities with reference to the basic mechanisms of species coexistence. Affinity analysis (similarity and mosaic diversity) measures the compositional pattern diversity, which is the function of the variation in species richness. We discuss the indicative versus the predictive value of these measures of biodiversity as regards ecological factors and processes and their application for conservation purposes.     

Diversity patterns of wet meadows along geochemical gradients in central Spain

Four measures of biodiversity (species number per site, total species number, mean similarity and mosaic diversity) and their relationships with soil chemical composition were studied in vascular plant communities in groundwater discharge ecosystems of central Spain. Species richness decreased with increasing salinity, alkalinity and halite concentration. Species richness was apparently controlled more by soil toxicity than by soil nutrient levels, although a positive correlation of Ca²⁺ with species richness was found after accounting for the effects of toxic compounds. All relationships were strictly monotonic. Six community types were identified based on their soil chemical characteristics: glycophyte, subglycophyte, tolerant, subalkalinophyte, alkalinophyte, and halocalcicole communities. Within community types, species richness showed very few significant relationships with soil characteristics. Mean species richness was lowest in the environmentally stressful communities. Total species richness was greatest in the ecotonal community type. Mean similarity, a measure of among-community diversity, and mosaic diversity, a measure of landscape complexity, differed among community types. Mean similarity was smaller (higher diversity) in species-poor community types, while mosaic diversity was greatest (greater complexity) in species-rich community types. The halocalcicole community type was richest in rare species.     

Disturbance and diversity at two spatial scales

The spatial scale of disturbance is a factor potentially influencing the relationship between disturbance and diversity. There has been discussion on whether disturbances that affect local communities and create a mosaic of patches in different successional stages have the same effect on diversity as regional disturbances that affect the whole landscape. In a microcosm experiment with metacommunities of aquatic protists, we compared the effect of local and regional disturbances on the disturbance–diversity relationship. Local disturbances destroyed entire local communities of the metacommunity and required reimmigration from neighboring communities, while regional disturbances affected the whole metacommunity but left part of each local community intact. Both disturbance types led to a negative relationship between disturbance intensity and Shannon diversity. With strong local disturbance, this decrease in diversity was due to species loss, while strong regional disturbance had no effect on species richness but reduced the evenness of the community. Growth rate appeared to be the most important trait for survival after strong local disturbance and dominance after strong regional disturbance. The pattern of the disturbance–diversity relationship was similar for both local and regional diversity. Although local disturbances at least temporally increased beta diversity by creating a mosaic of differently disturbed patches, this high dissimilarity did not result in regional diversity being increased relative to local diversity. The disturbance–diversity relationship was negative for both scales of diversity. The flat competitive hierarchy and absence of a trade-off between competition and colonization ability are a likely explanation for this pattern.     

Finding spatial regularity in mosaic landscapes: two methods integrated

Two methods were employed to find spatial regularity in a complicated mountain landscape of Beijing, China on the basis of functional and structural affinities. The first approach applied Affinity Analysis based on species composition to landscape. The mosaic diversity of the landscape was 3.5298>3, which means the study landscape is complex and controlled by multiple environmental gradients. These landscape types were divided into 3 parts according to the mean affinity values of 0.2143 and 0.7857 (0.5±1 SD). Modal sites are the central types of the landscape, which include a zonal broad-leaved forest of the region and a conifer plantation replacing the former. Outliers are found in the highest altitude and the lowest, both have few species in common with the above two modal types. The remaining landscape types are intermediate sites, which are transitional between modals and outliers, broadly distributed throughout mountain environments. Neighbor types have more species in common than those more widely separated, which probably distributed adjacently in space or in similar quality habitat. The other method employed is the new TWINSPAN analysis by substituting spatial neighboring data of landscape types for species composition data. It clearly divided the landscape types into three groups, i.e., subalpine, middle and low mountain groups, which were correlated with altitude, as well as influenced by human disturbance. The new TWINSPAN classification method is more reliable in finding spatial gradient of patchy landscapes than affinity analysis; however, affinity analysis is useful in finding species diversity pattern and the importance of landscape types in a region. Integrating advantages of the two methods could supply complete and reliable information on how landscape types are distributed in space, which environmental gradient dominates the spatial distribution of the landscape types, as well as where important and unusual types are located.     

Multifaceted Analysis of Patch-Level Plant Diversity in Response to Landscape Spatial Pattern and History on Mediterranean Dunes

Landscape structure is known to critically affect biodiversity. However, although the multi-facetted character of biodiversity is widely recognized, few studies have linked landscape spatial pattern and history simultaneously to multiple facets (taxonomic, functional, and phylogenetic) and spatial components (α, β, and γ) of plant diversity. We set out to reveal whether landscape parameters have specific effects on the separate diversity facets and components of plant diversity at a patch scale on coastal dune landscapes of Central Italy. For each landscape patch, we computed a set of patch-based metrics relying on multi-temporal land-cover maps. Based on a database of plant community plots, on functional traits from field measurements and on a dated phylogenetic tree, we calculated taxonomic (TD), functional (FD), and phylogenetic diversity (PD) within each patch at α, β, and γ level. Diversity measures were then related to the landscape metrics via linear mixed-effect models. Landscape pattern and transformations affected TD only moderately in coastal dune ecosystems. We found much stronger and contrasted effects on FD and PD. FD increased in patches surrounded by human-dominated habitats; PD was higher in fragmented patches, particularly in the Mediterranean macchia. Moreover, landscape pattern affected differently the single communities, the turnover among communities and the pool of species within the patch (α, β, and γ components). Our results call for the combined inclusion of FD and PD and their partitions into ecological analyses, being TD too crude to capture the comprehensive and contrasted response of plant diversity to landscape spatial pattern.     

Partitioning the diversity of riverine fish: the roles of habitat types and non-native species

1. Quantifying how biological diversity is distributed in the landscape is one of the central themes of conservation ecology. For this purpose, landscape classifications are being intensively used in conservation planning and biodiversity management, although there is still little information about their efficacy. 2. I used data from 158 running water sites in Hungary to examine the contribution of six a priori established habitat types to regional level diversity of fish assemblages. Three community measures [species richness, diversity (Shannon, Simpson indices), assemblage composition] were examined at two assemblage levels (entire assemblage, the native assemblage). The relative role of non‐native species was quantified to examine their contribution to patterns in diversity in this strongly human influenced landscape. 3. Additive diversity partitioning revealed the primary importance of beta diversity (i.e. among‐site factors) to patterns in species richness. Landscape‐scale patterns in species richness were best explained by between‐habitat type (beta₂: 41.2%), followed by within‐habitat type (beta₁: 37.7%) and finally within‐site (alpha: 21.1%) diversity. Diversity indices showed patterns different from species richness, indicating the importance of relative abundance distributions on the results. Exclusion of non‐natives from the analysis gave similar results to the entire‐assemblage level analysis. 4. Canonical analysis of principal coordinates, complemented with indicator species analysis justified the separation of fish assemblages among the habitat types, although classification error was high. Multivariate dispersion, a measure of compositional beta diversity, showed significant differences among the habitat types. Contrary to species diversity (i.e. richness, diversity indices), patterns in compositional diversity were strongly influenced by the exclusion of non‐natives from the analyses. 5. This study is the first to quantify how running water habitat types contribute to fish diversity at the landscape scale and how non‐native species influence this pattern. These results on riverine fish assemblages support the hypothesis that environmental variability (i.e. the diversity of habitat types) is an indication of biodiversity and can be used in large‐scale conservation designs. The study emphasises the joint application of additive diversity partitioning and multivariate statistics when exploring the contribution of landscape components to the overall biodiversity of the landscape mosaic.     

Land-use diversity index: a new means of detecting diversity at landscape level

Preservation of ecological diversity is a guiding principle of landscape management and planning. Although diversity is often quantified with measurable indices, common approaches used to measure diversity, for example the Shannon–Weaver index, are not adequate for many landscape studies, because they are affected by scale and sampling efforts. A robust index for measurement of landscape diversity should be able to quantify distinctive components of a landscape mosaic. This paper provides a new diversity index for landscape studies that improves the measurement of diversity at landscape level. The key features of the method are inclusion of an implication of physical moment and quantification of diversity by placing greater weight on the structure and composition of a patch. We have named the new index the land-use diversity index, or LUDI, and have concluded that the LUDI is the preferred measure of diversity at landscape level.