Spider Community Structure Research Articles

Biotic and abiotic factors drive multi-trophic interactions among spiders at different spatial scales in urban greenspaces

Abstract Urbanization is often detrimental to biodiversity, yet urban greenspaces can be managed to provide habitat for many arthropods. Understanding how anthropogenic filters influence processes of community assembly in urban ecosystems will inform conservation of species such as spiders, which provide natural pest control. Spiders are abundant in urban areas, but the relative importance of biotic and abiotic factors for structuring spider communities in urban greenspaces is unclear. We initiated the Cleveland Pocket Prairie Project in the legacy city of Cleveland, Ohio, where vacant lots and urban prairies were established across eight inner-city neighborhoods. In each greenspace, spiders were collected along with landscape and local environmental data in July 2017. Using a path analysis approach, we investigated the relative importance and strength of landscape and local environmental filters for influencing the structure of spider communities during mid-summer within this system. We found that spider community assembly was influenced by multiple abiotic and biotic drivers across spatial scales related to landscape composition, soil texture and quality, prey breadth, and habitat management designs. Web-building and active hunting spiders responded differently to these landscape and local drivers, highlighting the need to incorporate a functional perspective when studying community assembly. These findings suggest that a multi-scale approach to conservation management is needed to support biodiversity and associated biological control services in urban ecosystems.

Toxic effect of Cd burden on the gut microflora and immune responses of wolf spider Pardosa pseudoannulata

Spiders are dominant predators in the paddy ecosystem, but the immunotoxicity induced by environmental contaminants like heavy metals is still largely unknown. The gut microbiota-host interaction was the basic immune mechanism discovered in the arthropods. Here, we investigated the gut microflora and immune responses of wolf spider Pardosa pseudoannulata under Cd burden. Cd exposure was identified to shape the gut microbial community structure of spiders, with increased levels of Firmicutes and pathogens, and decreased levels of Proteobacteria and Bacteroidota. The alteration of microbiota-derived immune messengers like peptidoglycan (PGN) was also observed. ELISA and hemolymph metabolomic analysis showed that the activities of immune effectors phenoloxidase (PO) and lysozyme (LZM) and the abundance of tyrosine derivates were decreased, which indicated the suppression of Cd on the melanization immune response of spiders. Correlation analysis revealed a close relationship between the impaired immune system and the disordered microbiota. This study provides insight into the underlying mechanisms of the gut microflora-immune system interaction of P. pseudoannulata in response to Cd burden.

Non-native Douglas fir promotes epigeal spider density, but has a mixed effect on functional diversity

With climate change altering ecosystems worldwide, forest management in Europe is increasingly relying on more adaptable non-native tree species, such as Douglas fir (Pseudotsuga menziesii). However, the ecological consequences of the increased utilization of Douglas fir on arthropod diversity and ecosystem functioning are not fully known. Here we assessed how non-native Douglas fir as well as large- and small-scale differences in the environmental context, affect epigeal spider abundance, biomass, taxonomic and functional diversity, and community structure in Central European forests. Our study sites were divided into two regions with large differences in environmental conditions, with seven replicates of five stand types, including monocultures of native European beech (Fagus sylvatica), non-native Douglas fir and native Norway spruce (Picea abies), as well as two-species mixtures of European beech and each of the conifers. Contrary to our expectations, Douglas fir promoted small-scale spider diversity, and abundance and biomass (activity density). On the other hand, it decreased spider functional divergence and altered spider community structure. Microhabitat characteristics had opposing effects on spider diversity and activity density, with more open stands harboring a more diverse but less abundant spider community. Overall, our findings suggest that increasing Douglas fir utilization at the expense of Norway spruce does not necessarily decrease the diversity of epigeal arthropods and may even promote local spider diversity and activity density. However, care needs to be taken in terms of biodiversity conservation because typical forest spider species and their functional divergence were more strongly associated with native beech than with coniferous stands.

The effect of seabird presence and seasonality on ground-active spider communities across temperate islands.

Seabirds influence island ecosystems through nutrient additions and physical disturbance. These influences can have opposing effects on an island's invertebrate predator populations. Spiders (order: Araneae) are an important predator in many terrestrial island ecosystems, yet little is known about how seabird presence influences spider communities at the intraisland scale, or how they respond to seasonality in seabird colony attendance.We investigated the effects of seabird presence and seasonality on ground-active spider community structure (activity-density, family-level richness, age class, and sex structure) and composition at the family-level across five short-tailed shearwater breeding islands around south-eastern Tasmania, Australia. Using 75 pitfall traps (15 per island), spiders were collected inside, near, and outside seabird colonies on each island, at five different stages of the short-tailed shearwater breeding cycle over a year. Pitfall traps were deployed for a total of 2674 days, capturing 1592 spiders from 26 families with Linyphiidae and Lycosidae the most common. Spider activity-density was generally greater inside than outside seabird colonies, while family-level richness was generally higher outside seabird colonies. For these islands, seabird breeding stage did not affect activity-densities, but there were some seasonal changes in age class and sex structures with more adult males captured during winter. Our results provide some of the first insights into the spatial and temporal influences seabirds have on spider communities. We also provide some of the first records of spider family occurrences for south-eastern Tasmanian islands, which will provide an important baseline for assessing future change.

Four-year study of arthropod taxonomic and functional responses to a forest wildfire: Epigeic ants and spiders are affected differently

When studying forest disturbances, it is essential to examine biodiversity from different perspectives, which includes considering its taxonomic and functional facets. Indeed, different taxa may respond differently based on their functional traits. We analyzed the short-term effects of a wildfire on epigeic ant and spider communities in a Mediterranean forest. We specifically hypothesized that (1) fire would initially decrease the taxonomic and functional diversity of both taxonomic communities and have a more pronounced effect on spiders than ants because spider nests are shallower than ant nests and are consequently more vulnerable to fire; (2) recovery time would be longer for spiders than ants; and (3) the responses of taxonomic and functional diversity would be dependent on the identities and functional traits of the species found in both taxa. Our results show that wildfire affected the structure and composition of both communities but had a greater influence on ants. Over the four years of the study, these effects were largely constant for ants, whereas spiders displayed recovery. The two facets of diversity showed parallel responses to fire in the structure and composition of ant communities and in the composition of spider communities. However, the taxonomic and functional structure of spider communities reacted differently. In both spiders and ants, we observed that burned plots hosted species typical of open habitats, while unburned plots hosted species typical of vegetated habitats. We highlight the importance of (1) conducting long-term post-fire monitoring to get an accurate estimate of ecosystem recovery relative to pre-fire conditions and (2) studying taxonomic and functional responses to fire in different taxa to increase the power of the ecosystem response predictions used in habitat management decisions.

Ground-dwelling Spider Communities Respond to Changes in Riparian Vegetation Widths.

Spiders play a key role in the ecological dynamics in riparian habitats. However, most studies on the effects of changes in riparian habitats on spider communities have focused on the conversion of riparian forest to other land uses rather than on a gradient of forest widths. We assessed the community structure of ground-dwelling spiders in riparian vegetation fragments with varying widths in Southern Brazil. We selected four fragments with different riparian vegetation widths (> 40 m; < 30 m; < 15 m; < 5 m). In each fragment, spiders were seasonally collected using pitfall traps. We tested the effects of riparian vegetation widths and environmental variables (litter height, litter cover and canopy openness) on the taxonomic and guild composition of spider communities. The taxonomic and guild composition of ground-dwelling spiders varied among the widest (> 40 and < 30 m) and narrower riparian widths (< 15 m and < 5 m). While hunting spiders were associated with the narrower widths, web-building spiders were associated with the wider widths. Spider composition was influenced by the leaf litter height in the widest widths (> 40 and < 30 m) and by canopy openness in the narrowest width (< 15 m). Reductions in riparian vegetation were associated with significant changes in the community structure of ground-dwelling spiders, likely through top-down mechanisms associated with the higher litter input in wider fragments. In summary, the fragmentation of the riparian forests of Sothern Brazil are negatively associated with web-building spiders.

Contrasting beta diversity of spiders, carabids, and ants at local and regional scales in a black soil region, northeast China

Understanding the factors determining the formation of each community and metacommunity across a landscape is one of the most important ideas in soil animal ecology. However, the variables and parameters that shape soil arthropod communities in agroecosystems have not been resolved. These arthropods can serve as important bioindicators of field management and its sustainability. We sampled five corn plantations in each of three locations across a region spanning 600 km to come up with these determinants of the community structure of ground-dwelling spiders (Erigoninae: Araneae), carabids (Coleoptera: Carabidae), and ants (Hymenoptera: Formicidae). The analysis of the five fields within each of the three locations represent our local-scale samples, while the comparisons of the 15 sites across all three locations represent the regional scale samples. We tested the hypothesis that in the models we sampled, environmental/soil variables would drive community assembly locally (within location comparisons), but at the regional scale (between location comparisons), climatic and spatial variables would drive metacommunity assembly. The outcomes of our study showed distinct communities at each of the three locations when compared across regions but locally, fields were similar in species composition, as expected. Locally, spatial variables were important but not soil variables, regulated species richness and abundance. Turnover contributed more than nestedness to explain the biodiversity of spiders, carabids, and ants at both the local and regional scales. Neither purely climate variables, nor purely soil or spatial variables were significant enough explanations for the regional scale arthropod community composition. However, spatially structured environmental factors contributed most to explain the patterns supporting our hypothesis. We conclude that biodiversity in this agroecosystem area can be promoted by a mosaic of land uses being encouraged to increase landscape complexity at the regional scale.

How Iberian are we? Mediterranean climate determines structure and endemicity of spider communities in Iberian oak forests

Understanding the causes behind species richness and endemicity is fundamental to explain biodiversity and assist conservation management, especially in biodiversity hotspots like the Mediterranean Basin. Here we investigate the patterns in Iberian forest spider communities and the processes behind their assembly, by testing hypotheses about the effects of climate and habitat on species richness, endemicity and structure of communities at different spatial scales, and about how microhabitat and dispersal affect the level of endemicity of species. We studied 16 spider communities in Iberian Quercus forests from different climatic zones, applying a standardised sampling protocol. We examined the contribution of habitat, climate, and geography to the differences in the composition of spider communities across spatial scales using distance-based redundancy analysis models (dbRDA) and principal coordinates of neighbour matrices (PCNM). We assessed the effects of the same variables on the endemicity of communities (measured by a weighted index), and tested the correlation between the microhabitat and the ballooning frequency (obtained from bibliography), and the endemicity of species through generalised linear models. Spider communities formed two groups—one southern and one northern—based on similarity in species composition. Precipitation and temperature were inversely related with the number of species while geography and forest type explained the compositional similarities between communities at different spatial scales. Endemicity of communities increased with temperature and decreased with precipitation, whereas species endemicity decreased with ballooning frequency. Our findings illustrate how niche-related processes may drive spider diversity while dispersal determines species distribution and identity and, ultimately, community composition. From a conservation viewpoint, when maximising species richness is incompatible with prioritising endemicity, the criteria to follow may depend on the geographic scale at which decisions are made.

Riparian condition influences spider community structure and the contribution of aquatic carbon subsidies to terrestrial habitats

Degradation of riparian zones can alter aquatic and terrestrial communities of flora and fauna and disrupt their role in assimilating and mobilising carbon between the two ecosystems. Riparian spiders that predate on emergent aquatic invertebrates can contribute to carbon flux and the structure of aquatic and riparian food webs. The impact of riparian degradation on spiders in temperate rivers of Australia and their role in this broader ecosystem function is poorly understood. We surveyed the riparian zone of four rivers of south-western Australia in areas of natural intact vegetation and degraded agricultural land to explore whether riparian spider abundance, and diversity may be affected by changes to riparian condition. We also assessed the impact of the riparian condition on carbon fluxes between aquatic and terrestrial environments, using stable isotope analysis. We found overall abundance of riparian spiders was higher in degraded agricultural sites compared to natural intact sites and the structure of spider assemblages was different. Orb-weaver spiders (Araneidae and Tetragnathidae) were found to be more abundant in agricultural areas where canopy cover and understory are sparse as a result of livestock grazing and trampling. The contribution of carbon from aquatic invertebrates in a natural intact site was 48.5% for Orb-weavers and 41.6% for Cursorial Hunter spiders but reduced to 19.6% and 39.9% respectively in a degraded agricultural site. These results suggest that the position of spiders in riparian food webs and the amount of aquatic subsidy may change according to the condition and complexity of the riparian zone.

The community structure of beneficial and harmful arthropod fauna in rice field ecosysterms in lower Northern Thailand

The purpose of this current survey was to determine the community structure of insects and spiders that inhabit rice paddy fields. Six major locations of rice-growing areas were selected in lower northen Thailand i.e. Nakhon Sawan, Phetchabun, Phichit, Phitsanulok, Sukhothai and Uttaradit provinces. In each survey site, six sampling plots of paddy field were chosen and insects and spiders were caught using sweeping nets at 20 times/sampling plot during 2017-2019. All samples were identified based on external morphology. A total of 6,459 individuals of insects and spiders were collected, representing 102 species in 69 families and 11 orders. The rice paddies of Phitsanulok showed the highest diversity (73 species). In this regard, the species diversity (H’) for all insects and spiders of all rice-growing areas was considered relatively high (3.038). Meanwhile, the Evenness (J’) and Simpson index (1-D) in all rice paddies from the pooled data set out in this survey were 0.765 and 0.919, respectively. Phichit (H’ = 3.234) showed the highest species diversity index, whereas Phetchabun and Sukhothai (H’ = 2.895) had the lowest levels of diversity. Significant differences in species diversity indexes of six rice-growing sites were detected (P < 0.05) in all comparison. The insect order of Coleoptera had the highest recored species (21 species or 20.59%). It was found that the insect pests namely, Edwardsiama hergmanni (F. Cicadellidae), Dyscinetus morator (F. Scarabaeidae) and Nilaparvata lugens (F. Delphacidae) were the dominant species. Meanwhile, Micraspis discolor (F. Coccinellidae), Agriocnemis pygmaea (F. Coenagrionidae) Oxyopes javanus (F. Oxyopidae), Temelucha philippinensis (F. Ichneumonidae), Tropobracon schoenobii (F. Braconidae) and Goniozus nr. triangulifer (F. Bethylidae)] were mainly exhibited as natural enemies in this time. Additionally, the distribution of insects and spiders was aggregated for all rice-planting areas, as indicated by the values of variance to mean ratio (S2/) and the index of aggregation (Iδ).

Spontaneous recovery of functional diversity and rarity of ground-living spiders shed light on the conservation importance of recent woodlands

Secondary (or recent) woodlands, whose development is favoured by massive farmland abandonment, are increasingly seen as promising habitats that limit losses of biodiversity and ecosystem processes. The importance of temporal forest continuity (i.e. the duration of an uninterrupted forest state) for conservation of the forest fauna has been demonstrated for several taxa, but its influence on functional diversity and conservation importance of communities remains unclear. We studied how temporal continuity can shape taxonomic and functional composition and structure of forest-ground spider communities at a regional scale. According to broad-scale ecological site characteristics, species composition and—to a lesser extent—trait distribution substantially diverged between ancient and recent forest sites. Yet, we found hardly any significant differences in functional β-diversity, community structure, or conservation importance between the two forest categories. The only difference was for functional originality, which quantifies the average functional uniqueness of species within an assemblage: spiders’ communities of the ancient forests was more functionally original than those of the recent woodlands. Thus, in a conservation perspective, our study provides evidence that each forest harbours original species combinations, suggesting that each of them is irreplaceable, especially for ancient forests, which are functionally more original; however, recent woodlands have a high potential to spontaneously recover typical forest fauna communities with very similar structural and functional profiles to those of ancient forests.

Liming alters body size distribution in a community of epigeic spiders in birch forest (Betula pendula Roth)

Liming, an ameliorative method for acidified forest soils, affected the relative abundance of prey of ground-hunting spiders and consequently reduced densities of functionally similar species of these predators. Liming, an ameliorative method for acidified forest soils, may modify the structure of an arthropod community by altering the soil characteristics and/or the availability of food resources. We investigated the effect of liming on the community structure of ground-hunting spiders in a birch forest. We established six experimental birch stand plots. Each stand was exposed to one of three experimental treatments: control, 1.5 t/ha, or 3 t/ha of dolomitic limestone. We collected spiders using pitfall traps during 5 years. We characterized the community in terms of activity density, species richness, community-weighted mean body size, and functional diversity and evenness in body size. We further investigated the potential links through which the liming might affect spiders, namely soil characteristics, effect of liming on birch, and densities of potential prey. The commonly used dosage of 3 t/ha reduced densities of functionally similar species which led to the reduced functional evenness in body size and increased functional divergence in body size. Liming increased soil pH only slightly but decreased the densities of spiders’ preferred prey. The liming affected the community of ground-hunting spiders, at least partially, through reduced densities of their preferred prey.

Early summer aspect of the population of ground–dwelling spiders (aranei), harvestmen (opiliones) and ground beetles (coleoptera, carabidae) in pinus sibirica forests of Shorsky national park

The early summer structure of the communities of ground-dwelling spiders, harvestmen and carabids in Pinus sibirica forests of the Shorsky National Park has been studied for five years. The community was found to consist of 39 spider, 5 harvestman and 12 carabid species. Among spiders,small-sized litter-dwelling web-producing spiders (Linyphiidae) predominated, accounting for over 70 % of collected specimens. The community of wolfspiders (Lycosidae) was small and taxonomically poor, their dynamic density in the study area being rather low and unstable. Although spider species outnumbered the other studied groups, their population was generally scant and unstable. The composition of spider dominants varied among years, their dynamic densities and shares were unstable even in regularly collected species. Pairwise comparisons of the early summer structure of spider communities in different years did not always show statistically significant differences. Early summer communities of harvestmen in Pinus sibirica forests were predominated by juveniles of Mitopus morio (Fabricius, 1779), with first emergences of newly hatched Oligolophus tridens nymphs (C. L. Koch, 1836). The most abundant among eurychronic species was Sabacon sergeidedicatum Martens, 1989. In the early summer beetle community, the family Carabidae was the dominant group of ground-dwelling arthropods. The dominants complex was stable, and included Carabus aeruginosus Fischer von Waldheim, 1822, Pterostichus monticoloides Shilenkov, 1995, P. oblongopunctatus (Fabricius, 1787), and P. virescens (Gebler, 1833). Their population structure did not vary significantly among years. The Sorensen similarity indexes for the species composition of carabid communities in among-year pairwise comparisons were oftener higher than those for spiders.

Assessing spider diversity in grasslands – does pitfall trap color matter?

We analyzed effects of pitfall trap color on spider catches using four different pitfall trap colors (white, yellow, green, brown). For each color, we installed 17 pitfall traps at two grassland sites, respectively, and sampled 77 species from 6,202 individuals. Number of species showed no significant differences but Shannon- and Simpson-diversity were significantly higher in green and brown traps while number of individuals increased in white ones. Species inventories were not complete in the different pitfall trap colors but species accumulation increased significantly slower in white and brown traps. Trap color significantly affected hunting type with ground hunters being associated with bright and web-builders associated with dark colors. Attractiveness of different trap colors may arise due to differences in biological preconditions, albedo and microclimate which in turn can affect diversity and community structure of spiders. Trap color has a significant impact on spider catches and should be considered when planning surveys. We recommend the use of a combination of white and brown (or transparent) pitfall traps to gain complete and diverse species inventories in spiders.

Abiotic factors and biotic interactions jointly drive spider assemblages in nest-boxes in mixed forests

Although spiders are common inhabitants of tree cavities, factors that drive their community structure in these microhabitats are little known. Here we investigated whether bark type, season, intraguild predation (IGP) among spiders, and presence of vertebrate predators can influence the spider community structure in tree cavities. We examined spider abundance and the taxonomic and functional composition of spiders in nest-boxes within two mixed forest stands in central Slovakia in 2012–2013. In total, 1211 spiders belonging to 31 species were sampled from 60 nest-boxes at two sites over three seasons. Spider abundance peaked in autumn as spiders sought wintering sites. Guilds and taxonomic composition changed seasonally with spring and autumn communities dominated by “Other hunters” (Anyphaenidae, Clubionidae, Philodromidae) while during summer the community was dominated by “Sheet web weavers” (Linyphiidae). The guild and taxonomic turnover may be partly explained by the interaction between spiders' phenology and IGP exerted by winter-active spiders on smaller spiders from autumn until spring. Bark type influenced the guild composition as dominance of “Space web weavers” was higher in trees with rough bark than in trees with smooth bark. The rough bark also reduced the intensity of IGP by Anyphaena accentuata (Sundevall, 1833) on philodromids. The presence of insectivorous birds reduced the abundance of spiders by 67%. The presence of bird predators altered the guild composition as they affected mostly the web spiders. The results show that the biotic interactions and abiotic factors interactively determined the spider community structure in the nest-boxes depending on spiders' functional traits.

Community Structure of Spiders in Sulphur-Polluted Habitats in the Karkonosze Mts (Poland)

ABSTRACT Spiders are considered to be sensitive to habitat pollution, but the effect of sulphur contamination on spider communities is poorly known and studied, although the impact of sulphur can be realized by the changes of soils and forest community. This work examined the diversity of ground-dwelling spiders in sulphur-contaminated habitat among three types of studied biotopes (deforested area, thicket, spruce forest) in the area of the Karkonosze Mountains (Sudetes Mountain System) in Poland. In the late 1970s and 1980s, a large-area forest decline in Sudetes Mountains, mainly derived from industrial emissions caused drastic changes in abiotic environment leading to the fundamental forest ecosystem transformation. The results of these damages were studied directly after the forest decline took place. Nowadays, more than 20 years after the ecological disaster, 13 sites were chosen according to habitat type to study the long-term impact of sulphur on spiders. The sites with high and low sulphur content...

Deer herbivory reduces web-building spider abundance by simplifying forest vegetation structure.

Indirect ecological effects are a common feature of ecological systems, arising when one species affects interactions among two or more other species. We examined how browsing by white-tailed deer (Odocoileus virginianus) indirectly affected the abundance and composition of a web-building spider guild through their effects on the structure of the ground and shrub layers of northern hardwood forests. We examined paired plots consisting of deer-free and control plots in the Allegheny Plateau region Pennsylvania and Northern Highlands region of Wisconsin. We recorded the abundance of seven types of webs, each corresponding to a family of web-building spiders. We quantified vegetation structure and habitat suitability for the spiders by computing a web scaffold availability index (WSAI) at 0.5 m and 1.0 m above the ground. At Northern Highlands sites, we recorded prey availability. Spider webs were twice as abundant in deer-free plots compared to control plots, while WSAI was 7–12 times greater in deerfree plots. Prey availability was lower in deer-free plots. With the exception of funnel web-builders, all spider web types were significantly more abundant in deer-free plots. Both deer exclusion and the geographic region of plots were significant predictors of spider community structure. In closed canopy forests with high browsing pressure, the low density of tree saplings and shrubs provides few locations for web-building spiders to anchor webs. Recruitment of these spiders may become coupled with forest disturbance events that increase tree and shrub recruitment. By modifying habitat structure, deer appear to indirectly modify arthropod food web interactions. As deer populations have increased in eastern North America over the past several decades, the effects of deer on web-building spiders may be widespread.

Non-crop plant communities conserve spider populations in chili pepper agroecosystems

Habitat management enhances heterogeneity in agroecosystems and also has the potential to increase recruitment of spiders, which can improve the biological control services afforded by these important predators. A paucity of studies has documented the associations of spiders with plant communities or the efficacy of non-crop plants for increasing the density and diversity of spider populations. Here we examined natural associations of spiders with native non-crop plants within Brazilian chili pepper agroecosystems. Following this characterization, a manipulative experiment was undertaken at two locations to identify the effects of non-crop plant strips and borders on spider community structure. The composition of native plants altered the community of spiders. The abundance of these predatory spiders was highest on Asteraceae. Spatial Analyses by Distance Indices (SADIE) determined that there was significant aggregation of spiders in chili pepper fields under these plant management strategies. Although incorporating this habitat management approach reduced the overall cropping area, the corresponding increase in generalist predator abundance could offset costs by improving the natural control of pests. This study revealed associations between native plants and spider communities, and how these help to conserve predator biodiversity. Targeted management of native non-crop plants promote the abundance of natural enemies and enhances biological control in chili pepper agroecosystems.

The arthropod community of boreal Norway spruce forests responds variably to stump harvesting

Forest fuel harvesting increases the need to collect not just logging residues but also tree stumps from harvested stands. This biomass removal has raised concern over forest biodiversity. Here, the effects of stump harvesting on spiders, ants, harvestmen, ground beetles and epiedaphic springtails occupying boreal Norway spruce (Picea abies) forest floor were studied two and five years after harvesting by comparing pitfall trap samples from clear-cut sites with and without subsequent stump harvesting and from unharvested mature forests in central Finland. At harvested sites, traps were placed both on intact and exposed mineral soil surface. Open-habitat and generalist ground beetles benefitted from the stump harvesting, but generally the numbers of arthropods between stump harvesting treatments and different aged clear-cuts were rather similar. The intact forest floor hosted more ants, springtails and harvestmen than did the exposed mineral soil. Moreover, the community structure of spiders, ground beetles and springtails was affected by stump harvesting, forest-floor quality (intact or exposed), and time elapsed since harvesting. Based on these results we recommend minimizing the exposure of mineral soil during management practices. However, more long-term studies are required to document the development of fauna in the harvested areas and the ecosystem-level impacts of utilization of forest biomass for energy.

海南天然林与橡胶林蜘蛛多样性比较

PDF HTML阅读 XML下载 导出引用 引用提醒 海南天然林与橡胶林蜘蛛多样性比较 DOI: 10.5846/stxb201408191643 作者: 作者单位: 湖北大学、重庆大学,湖北大学生命科学学院，行为生态与进化中心，生物资源绿色转化湖北省协同创新中心,重庆大学资源及环境科学学院,湖北大学生命科学学院，行为生态与进化中心，生物资源绿色转化湖北省协同创新中心 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金(31172113, 31272268);湖北省自然科学基金(2014CFB544);湖北省教育厅青年基金(Q20141001) Composition and diversity of spiders in the rubber plantation and natural forest of Hainan Island, China Author: Affiliation: Hubei University,,,Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Centre for Behavioural Ecology and Evolution, College of Life Sciences, Hubei University, Wuhan 430062, China Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:为探索天然林和橡胶林蜘蛛多样性现状,于2010 年8 月在海南黎母山自然保护区选取天然林和橡胶林,采用扫网法、陷阱法和单位面积法收集蜘蛛标本,分析两种林型之间蜘蛛组成、多样性和功能群差异,并以蜘蛛科和数量分布为属性进行主成分分析(PCA),探讨林型中样方之间蜘蛛群落的相似性。共采集蜘蛛标本3609 头,用于统计分析的成蛛969 头,归属于23 科,162 种。天然林20 科,100 种,优势类群为跳蛛科、球蛛科和园蛛科;橡胶林17 科,87 种,优势类群为肖蛸蛛科、狼蛛科和猫蛛科。从蜘蛛的数量分布看,橡胶林蜘蛛个体密度显著高于天然林;而天然林多样性指数和丰富度指数显著高于橡胶林。橡胶林中结圆网型和游猎型蜘蛛显著高于天然林,结皿网型显著低于天然林,伏击型不存在显著性差异。PCA分析结果表明,24 个样方趋于分成天然林和橡胶林2 组,并且天然林样方之间相似性极高,而橡胶林样方之间相似性相对较低。以上结果表明:(1)橡胶林替代天然林后蜘蛛群落结构发生变化,多样性降低;(2)增加生境结构的复杂性和减少人为干扰对保护和恢复物种多样性有重要意义。 Abstract:The present study compares the community dynamics of spiders in the rubber plantation of Hainan Island to those of spiders in the island's natural forest. Hainan, which is the fifth largest rubber producer in the world, is the second largest island in China. It features a tropical climate, and is located in the South China Sea. Rubber plantations are commonly considered "Green Deserts", as the expansion of rubber plantations has caused a series of ecological problems, including habitat fragmentation, biodiversity loss, habitat loss, soil erosion, and climate change. Of the arthropods, spiders comprise a group known to measure changes in habitat structure, habitat type, wind, and temperature exposure, and play key ecological roles as predators. Spider assemblages, which are easily sampled, are useful indicators that can be used to compare the biodiversity of various environments and assess the effects of disturbances on diversity. Because spiders are generally found in forests in high abundance, they form a good model taxa for biodiversity studies. In addition, their distributions and abundances are linked to the structural attributes of their habitat. They play key functional roles in ecosystems, and their abundance, richness, and community structure in tree canopies are associated with the complexity of the ecosystem's vegetative structure. To compare the composition and diversity of spiders in a natural forest and a rubber plantation, spider communities in 6 plots (three repetitions for each forest type) were investigated during four field trips in August 2010, using pitfall traps, direct searching, and sweep-netting. The similarity analysis of samples from the natural forest and rubber plantation was conducted via the principal component analysis (PCA) of spider families and numbers of individuals. A total of 3609 individual spiders were collected from the two forests, 969 of which were identifiable adults representing 23 families and 162 species. From samplings of the natural forest, 20 families and 100 species were identified, in which the most abundant families were Salticidae, Theridiidae, and Araneidae. From the rubber plantation samples, 17 families and 87 species were identified, in which the most abundant families were Tetragnathidae, Lycosidae, and Oxyopidae. The abundance of spiders in the rubber plantation is significantly higher than that in the natural forest, but the Shannon -Wiener (H'), Simpson index (D), Evenness (J), and Richness (Dmg) are significantly higher in the natural forest than in the rubber plantation. In the rubber plantation, the abundance of orb weavers and cursorial hunter-spiders is significantly higher than that in the natural forest, while no significant difference can be detected between sheet-line weaver spiders and ambush predator spiders in the two forests. The results of the PCA indicate that the natural forest and rubber plantation are highly differentiated, with the sampling plots in the natural forest having a much higher degree of similarity than those in the rubber plantation. These results suggest that (1) spider community structure varies and its diversity decreases when rubber plantations replace natural forest, (2) increasing the complexity of habitat structure and reducing anthropogenic disturbance is a meaningful way to conserve and restore biodiversity. 参考文献 相似文献 引证文献