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Plant distribution patterns are influenced by many different factors. We examined mechanisms behind local distribution patterns of boreo‐nemoral fleshy‐fruited woody plants with seed dispersal mainly mediated by birds. It has been suggested that guilds of these plants develop 'orchards', i.e. locally aggregated occurrences composed of several species. We analysed spatially explicit occurrence data of different life stages of a local guild of fleshy‐fruited woody plants in south‐eastern Sweden, and conducted a seedling recruitment experiment for a subset of ten species. Spatial point pattern analyses showed that the guild of fleshy‐fruited species was aggregated at small (< 10 m) spatial scales. Saplings were more common under canopies of heterospecific reproductive individuals than expected by chance. These results show that the local guild of fleshy‐fruited species is distributed as orchards, i.e. clusters consisting of individuals of different species and life stages. We found no evidence of negative distance dependence between saplings and reproductive conspecific individuals. Results from the recruitment experiment suggest that recruitment is seed limited and generally low among the studied species. At the site‐scale (circular areas with 50 m radius), there was no difference in seedling recruitment between sites with and without reproductive conspecific individuals for most species included in the recruitment experiment. This further suggests that the aggregated patterns found are not simply a result of spatial concordance in suitable habitats across life stages. Instead, we suggest that the sheer number of seeds from species in the guild deposited under the crowns of fruit bearing individuals is the main mechanism behind the build‐up of orchards. Although further studies are needed to fully disentangle the processes underlying the observed patterns of local diversity, we argue that describing patterns and contrasting them to the predictions of ecologically relevant hypotheses is a useful first step. [ABSTRACT FROM AUTHOR]

Factors driving the spatial patterns of communities of sedentary organisms are still poorly understood. In this context parthenogenetic animals are useful to test the contribution of sexual and interspecific interactions on spatial patterns. As such, mixed communities of asexual and sexual species are expected to be spatially organized as a single sexual species, with sexes randomly distributed and mutually independent. During the reproductive period, we determined the instantaneous spatial structure in a community of Darevskia rock lizards from Armenia composed of one sexual species (D. valentini), two asexual species (D. armeniaca, D. unisexualis), and their hybrids. We also analysed the specific composition of clusters and the species segregation by habitat. We used the Ripley's K distance function to measure clustering spatial patterns, and the Delaunay's triangulation to identify the clusters and their specific composition. We estimated the spatial segregation among species by calculating the overlap between species pairs, by comparing pairwise distances from males to other males and from males to females, and by comparing the frequencies of both sexes and reproduction modes (asexual and sexual) in plant cover and height using log-linear models. Species displayed a clustered spatial structure, with parthenogens (mainly D. armeniaca) or their hybrids in all clusters. Females and males were concentrated in areas with medium plant cover. D. armeniaca and D. valentini were the species with the highest overlap. Males were closer to males than to females. This community displays an instantaneous spatial pattern resembling a population of a single sexual species. Spatial statistics offer new insights to analyse the spatial structure of species communities. [ABSTRACT FROM AUTHOR]

Plant and animal individuals can have a random, regular, or clustered distribution across space. The analyses of these patterns are important to understand how environment influences the spatial structure of species communities. We studied the local spatial segregation in a lizard community that is composed by four species in Salamanca (Spain). We inferred if habitat and / or competition are segregating factors. We collected a total of 675 records with a high-accuracy GPS unit. We used Ripley's K function to determine the distance threshold of clustering of the whole community and of each species separately, Delaunay's triangulation (using as clustering distance threshold the Nearest Neighbor Index) to identify spatial species' clusters, and an overlapping analysis (using buffers around species records), as well as a distance comparison analysis (among intra-species and inter-species distances), to measure the species' spatial segregation. The lizard community was distributed in 34 clusters, with 13 composed by only one species and 21 composed by two or more species. Our results indicated that species of the same genus segregated almost totally, inhabiting different habitats; on the other hand, species of different genera presented partial segregation, sharing some habitats. Ground-dwelling species had partial spatial segregation as they compete for similar habitats. Saxicolous species presented a high degree of spatial segregation due to their different habitat. [ABSTRACT FROM AUTHOR]