Myxomycete distribution varies among leaf litters of different vegetation in a local secondary forest of warm-temperate western Japan

Although many myxomycetes inhabit leaf litter on the forest floor and have feeding stages in litter layers, there has been little understanding regarding how the different types of leaf litter in a forest influence myxomycetes to distribute. In this study, I focused on the microhabitat distribution of foliicolous myxomycetes within a local secondary forest that consisted of various vegetation types in warm-temperate western Japan. Newly defoliated leaf litters were collected from the ground surfaces of seven different sites and then incubated in trays at a forested site throughout the entire fruiting seasons (in situ incubation method). Forty-eight species of myxomycetes (with varieties treated as species) were found in a total of 4042 samples. Leaf litters derived from different vegetation sites yielded diverse myxomycete assemblages, i.e. the Quercus glauca site yielded the richest myxomycete community (26 species), followed by Quercus variabilis site (24), Prunus verecunda site (22), Cinnamomum camphora site (21), Castanopsis cuspidata site (18), Pinus densiflora site (7) and bamboo site (7). Several myxomycete species were found to be preferentially distributed in deciduous broadleaf or evergreen leaf litter. The fraction of vegetative cover of deciduous and evergreen trees influenced the species richness and diversity of myxomycetes. Leaf litter heterogeneity derived from forest vegetation and defoliation season influenced the myxomycete distribution and species diversity. Research using in situ incubation method demonstrated that heterogeneous myxomycete microhabitats are distributed at a small spatial scale in a local forest.     

Inflorescences of Neotropical herbs as a newly discovered microhabitat for myxomycetes

An assemblage of myxomycetes associated with inflorescences of large Neotropical herbs, a microhabitat not previously known to support these organisms, is described and characterized ecologically from a number of study sites in Costa Rica, Ecuador, and Puerto Rico. Thirty-one different taxa were found among 652 specimens of myxomycetes recorded in the field or obtained from 358 moist chamber cultures prepared with decaying floral parts. A comparison with the results of 696 moist chamber cultures prepared with various other litter substrates showed that thirteen myxomycete taxa occurred more often on inflorescences. Six taxa had a strong preference for this microhabitat, and three of those seem to be new for the Neotropics. Correspondence analysis of the data set compiled for inflorescences indicated that the assemblage of myxomycetes was relatively consistent across all of the various study sites. The actual myxomycete substrates were the rapidly decaying floral parts enclosed by the massive, still living bracts. Richest in myxomycetes were species of Heliconia and Costus. Here, nectar residuals probably promoted a rapidly developing community of yeasts and bacteria. A high density of these organisms was indicated by the frequent occurrence of myxobacteria in the moist chamber cultures prepared with floral parts. Results from canonical correspondence analysis suggested that a substrate pH between 8 and 9 and the presence of massive, compact inflorescences on plants occurring at lower elevations in localities with moderate annual rainfall provide optimal conditions for inflorescence-inhabiting myxomycetes. An incidental dispersal of myxomycete spores by birds that pollinate the flowers or feed upon the fruits seems possible and may have accounted for the high degree of preference exhibited by some of the inflorescence-inhabiting myxomycetes, for which the term "floricolous" is proposed.     

Community of dark-spored myxomycetes in ground litter and soil of taiga forest (Nizhne-Svirskiy Reserve,Russia) revealed by DNA metabarcoding

The diversity of dark-spored myxomycetes in forest ground litter and soil from four study plots across a fire chronosequence in Nizhne-Svirskiy Nature Reserve (northwest of Russia) was assessed by a DNA metabarcoding approach. The history of fire disturbances and the season of sampling influenced the composition of myxomycete assemblages. Several species showed substrate preferences different from what is known from fruiting body records. A high abundance of nivicolous species in the majority of the samples suggests that this ecological group constitutes a common element of soil microbial communities in lowland taiga forests. Four species are reported for the Leningrad region for the first time. Our results support the hypothesis that amoebae populations of myxomycetes may have much wider ecological niches than indicated by records of fructifications, and further environmental studies may provide valuable new insights on myxomycete ecology and distribution.     

Seasonal occurrence and distribution of myxomycetes on different types of leaf litter in a warm temperate forest of western Japan

The seasonal occurrence and distribution of myxomycetes on different types of newly defoliated leaf litter were examined in a secondary forest in a warm temperate region of western Japan. The two types of leaf litter (deciduous trees, Prunus verecunda and Quercus variabilis, and evergreen trees, Q. glauca and Cinnamomum camphora) were incubated in trays on the forest floor. A total of 45 myxomycete species were recorded from 3021 collected samples that occurred at the July peak during the warmest and humidest season from April to November. The occurrence of species was significantly related to the changes in mean temperature and minimum temperature on both leaf types under humid conditions. Myxomycete assemblages were divided into three seasonal phases. Most of the species occurred in June–September, while a few species demonstrated characteristic distributions; i.e., Didymium melanospermum appeared in April– May and Diderma umbilicatum appeared in October– November. The respective leaf types supported the reproduction of myxomycetes with high species richness and diversity, with 34 species and H’ = 2.59 on deciduous trees and similarly 30 species and H’ = 2.49 on evergreen trees. Several species, however, exhibited a preference for either the deciduous tree or evergreen tree leaves. Thus, a mixed forest that defoliates during different two seasons yields a greater species diversity of myxomycete assemblage.     

宝天曼国家级自然保护区三种林型土壤的亮孢黏菌多样性

黏菌是土壤原生生物的重要组成部分,但其群落组成与多样性格局信息目前还不全面。本研究采用18S rRNA基因高通量测序的方法,研究了宝天曼自然保护区内落叶阔叶林、针叶林和针阔混交林土壤中的亮孢黏菌多样性,并通过多元统计方法分析了其群落结构与土壤环境因子之间的关系。结果表明,30份土壤样品中共获得26个亮孢黏菌的可操作分类单元（OTUs）,隶属团毛菌目Trichiales下的7个属。4个OTUs可注释到种,分别为球圆团网菌Arcyria globosa、蛇形半网菌Hemitrichia serpula、刺丝团毛菌Trichia scabra和高山团毛菌Trichia alpina。亮孢黏菌群落α多样性在不同林型间有显著差异,其中在针叶林最高,落叶阔叶林最低。不同林型土壤的亮孢黏菌群落结构也显著不同,冗余分析显示,不同林型间黏菌群落结构差异与土壤含水量、碳氮比、有效钾和有机碳显著相关,但总体土壤环境因子对群落结构差异的解释量有限,占比10.18%。本研究丰富了土壤黏菌多样性信息和生态分布理论。     

Functional and genetic diversity changes through time in a cloud forest ant assemblage

Climate change in the Neotropics is causing upslope range shifts. We used arrays of ant species collected in a cloud forest at 1,500 m in Área de Conservación Guanacaste (ACG), northwestern Costa Rica, collected in two time periods (1998–2000 and 2008–2011) to measure changes in species richness and diversity over a decade. Using metrics of community structure, we found that the species assemblage in the collections from the 1990s was significantly phylogenetically clustered and functionally less diverse as compared to collections from the early 2000s. At both time points, the assemblages were significantly phylogenetically clustered and while the difference in functional diversity between the time points was not significant, the ant assemblage has become lighter in color (on average) over time. When individual species are considered, the overall pattern of replacement is consistent with the cloud forest ant assemblage being colonized by arrivals from lower elevation forests. The invertebrate communities on cloud forested mountain tops are especially vulnerable to a changing climate as there are two factors working together; no higher terrain to which they can move and the invasion of more and more taxa from lower downslope. This vulnerability is already measurable.     

Patterns of occurrence of corticolous myxomycetes on white oak trees of two different size classes

Data were obtained on the assemblages of corticolous myxomycetes (plasmodial slime moulds or myxogastrids) associated with the bark surface of living white oak (Quercus alba) trees from two different size classes. Bark samples obtained from larger trees were characterized by higher values for both species richness and diversity when compared to those collected from smaller trees. This might have been expected since the former possess a larger surface area and presumably have persisted over a longer period of time. However, the myxomycete assemblage associated with smaller trees was appreciably different and did not simply represent a depauperate version of the assemblage associated with larger trees. This suggests that the differences observed between size classes cannot be simply attributed to size alone.     

Macroecology of high-elevation myxomycete assemblages in the northern Neotropics

A number of recent studies have been directed towards developing a more complete understanding of myxomycete ecology throughout the world. However, the lack of comparative data obtained using standard methodologies makes the results of these studies somewhat speculative. The objective of this investigation was to examine the evidence of macroecological patterns in myxomycete assemblages in high-elevation areas of the northern Neotropics. For this, a series of study areas in Mexico, Guatemala, and Costa Rica, as well as two external study areas (one in the United States and the other in Thailand), were selected to compare the diversity-environment relationships exhibited by myxomycetes. Altogether, the 2592 moist chamber cultures prepared yielded a total of 1377 myxomycete records, representing 89 different species. A trend of decreasing species richness with decreasing latitude was observed for the species assemblages associated with the study areas in the Neotropics. As latitude increased, species assemblages in the Neotropical study areas became increasingly similar to the temperate study area. The difference in species richness between study areas in Mexico and Thailand, along with the results obtained for a series of macroclimatic patterns evaluated in the study areas of the Neotropical region, suggests that forest structure plays an important role in the structure of myxomycete assemblages. In contrast, soil chemical characteristics and the pH of the substrates present seem to be indirectly related to the diversity estimators used for analysis, suggesting that they are probably more important at a smaller ecological scale.     

Instability of copronecrophagous beetle assemblages (Coleoptera: Scarabaeinae) in a mountainous tropical landscape of Mexico

We analyzed changes over time in species composition and functional guild structure (temporal beta diversity) for natural assemblages and those modified by humans in a fragmented, tropical mountain landscape. The assemblages belong to cloud forests (the original vegetation type), secondary forests, traditional shaded coffee plantations, commercial shaded coffee plantations, and a cattle pasture. Copronecrophagous beetles, subfamily Scarabaeinae (Insecta: Coleoptera: Scarabaeidae), were used as the indicator group. This group has been used in previous studies and other tropical forests and has been found to be a good indicator of the effects of anthropogenic change. For each assemblage, we compared samples that were collected several years apart. Changes were found in species composition, order of abundance, and in the proportion that a given species is present in the different functional groups. The changes that occurred between samplings affected the less abundant species in the cloud forest and in the pasture. In the other vegetation types, both abundant and less abundant species were affected. Their order of abundance and proportion in the different guilds also changed. This study shows that, although landscape richness remains relatively constant, richness at the local level (alpha diversity) changes notably even over short lapses of time. This could be a characteristic of landscapes with intermediate degrees of disturbance (such as those that have been partially modified for human use), where assemblage composition is very fluid.     

Breeding Birds in Riparian and Upland Dry Forests of the Cascade Range

ABSTRACT We quantified breeding bird abundance, diversity, and indicator species in riparian and upland dry forests along 6 third- to fourth-order streams on the east slope of the Cascade Range, Washington, USA. Upland dry forest on southerly aspects was dominated by open ponderosa pine (Pinus ponderosa) and dry Douglas-fir (Pseudotsuga menziesii) plant associations. Upland mesic forest on northerly aspects was dominated by closed-canopy Douglas-fir or dry grand fir (Abies grandis) plant associations. Riparian overstory vegetation was dominated by black cottonwood (Populus trichocarpa) plant associations with a prominent hardwood tree and shrub component. We quantified bird assemblages, diversity, and abundance from parallel point transects on riparian and adjacent dry and mesic upslope forests. We detected 80 bird species from >12,000 point-transect observations during 1998–1999. Eighteen species accounted for 75% of all detections. Species richness and evenness were similar in all 3 forest types, with approximately 35 species and high evenness (0.85) in each forest type. Bird species assemblages differed among dry, mesic, and riparian forest types, with the greatest differences between riparian and both dry and mesic upland forests. Riparian forest had the greatest number (9) of strong characteristic, or indictor, species among the 3 forest types. Upland mesic forest was characterized by 7 indicator species. Upland dry forest had 4 indicator species. Our results indicate that current standards and guidelines for riparian buffers zones would allow for avian refuge and corridor functions along these streams. Forest managers could use our indicator species to predict and monitor shifts in upland forest species composition from thinning and prescribed burning practices that are used to reduce fuels in uplands and to reduce continuity of fire effects between riparian and upland zones.     

Influence of bark pH on the occurrence and distribution of tree canopy myxomycete species

This study compares the occurrence and distribution of myxomycete species in the canopy of living trees and neighboring grapevines. Corticolous myxomycetes of three temperate forests in southeastern USA were studied on six tree species (30 trees) and grapevines (30 vines) to determine distribution and occurrence of myxomycete species relating to geographic location, host species, and bark pH. The double-rope climbing technique was used to access the canopy and sample bark up to 16.5 m. Bark samples were examined in 580 moist chamber cultures and 44 myxomycete species were identified representing 21 genera, averaging 3.0 +/- 2.1 species per sample site. Jaccard's coefficient determined community similarity between five individuals of six tree species, Acer saccharum, Fraxinus americana, Liquidambar styraciflua, Liriodendron tulipifera, Platanus occidentalis and Tsuga canadensis, and neighboring grapevines, Vitis aestivalis and V. vulpina. Vertical variation in species richness was significantly different only for Platanus occidentalis and might be attributable to flaking of bark with increasing height in the canopy. Tsuga canadensis and neighboring grapevines had greatest community similarity. Cribraria violacea was observed on all tree and grapevine species except T. canadensis and neighboring grapevines. Occurrence and species assemblages of myxomycetes were associated with bark pH, not geographic location. Bark of V. aestivalis (pH 4.5) was more acidic than neighboring T. canadensis (pH 4.1), compared to grapevines of the same species neighboring other tree species. Results indicated that most species are not regionally restricted, and although some myxomycetes are associated with a certain pH range, others develop on any substratum. Future research protocols for corticolous myxomycetes should emphasize sampling adequate amounts of substrata in a local region from different host species that have a wide range of bark pH, ensuring a representative sample of species for an entire region.     

后河保护区柳杉林中黏菌群落组成

柳杉是中国特有树种,对于广泛分布于森林生态系统的黏菌而言,单纯的柳杉林是一种特殊的生境。为探索柳杉林中黏菌的物种多样性,本研究在武陵山区东北部的湖北省后河国家级自然保护区柳杉林样地中采集柳杉树皮和凋落物,在120个培养湿室中,发生黏菌的湿室68个,占56.67%。从两种基物上获得黏菌6目7科12属24种,优势种为混淆筛菌Cribraria confusa,相对丰度达到19.01%。柳杉林凋落物上发生的黏菌种类和数量高于柳杉树皮,凋落物和柳杉树皮上发生的黏菌共有种为4种,种群间的Sørensen相似性系数为Cs=0.333。在不同季节间,黏菌物种的群落组成与多样性也表现出差异,春季Shannon-Wiener多样性指数Hʹ=0.2987±0.1564,夏季Hʹ=0.1105±0.0949,秋季Hʹ=0.1968±0.0589,冬季Hʹ=0.2726±0.0875。黏菌物种数量发生最多的是春季和冬季,均有15种,仅在春季发生的黏菌物种为粗壮发菌Comatricha suksdorfii、鲜黄绒泡菌Physarum luteolum、暗红团网菌Arcyria denudata和极小无丝菌Licea minima,仅在冬季发生的黏菌物种为钙丝绒泡菌Physarum decipiens、小筛菌Cribraria microcarpa和暗褐无丝菌Licea belmontiana。典型对应分析（canonical correspondence analyses,CCA）表明,影响柳杉林中黏菌物种群落组成与多样性的主要环境因素是基物类型。     

Effects of rain forest logging on species richness and assemblage composition of small mammals in Southeast Asia

Aim The effects of logging and habitat degradation on the richness and abundance of small mammals in Asian rain forests are largely unknown. This work compares the species richness, dominance and evenness of small non‐volant mammals between logged and unlogged forests, and assesses whether assemblage variability (β‐diversity) is similar between forest types. Location Southeast Asia, northern Borneo (Sabah, Malaysia), Sunda‐shelf. Methods We surveyed species‐rich assemblages of small non‐volant mammals in three unlogged and three logged forests for 2 years. At each forest site, we sampled a permanently marked transect and two additional sites in three trapping sessions. All analyses were performed at both levels to include the effects of local abundances and point estimates, separately from the relative abundances of species on a more regional scale. Results We trapped a total of 1218 individuals of 28 species. Eleven common species accounted for 95% of all captures. Species richness and diversity were significantly higher in unlogged forest (27 species) than in logged forest (17 species). This was mainly attributable to the smaller number of rarely recorded species in logged forest (five compared with 16 in unlogged forest, with a total of fewer than 10 captures). However, all common species were present in both logged and unlogged forests, and our analyses revealed similar patterns of dominance, evenness and fluctuations in abundance. Hence overall assemblage composition in multivariate space did not differ greatly between forest types. Assemblages of Muridae and Tupaiidae showed similar population fluctuations in space and time, indicating that the ecology of these taxa may be partially driven by the same environmental factors. Main conclusions Although species were distributed patchily within sites, analyses at local and regional scales revealed similar patterns in diversity and assemblage variability, suggesting that effects of forest modification did not differ extensively locally and regionally, but had a profound effect on rare species. Our results emphasize the importance and conservation value of logged forest stands that are able to hold a large proportion of the small mammals also found in unlogged forests. Rare and more specialized species are more vulnerable to forest degradation than commonly caught species, resulting in the complete loss, or a decrease in numbers, of certain groups, such as arboreal small mammals and Viverridae.     

Beetle species richness along the forest productivity gradient in northern Finland

The occurrence and habitat associations of the majority of invertebrate groups in boreal forests are poorly known, even though these groups represent perhaps over 99% of the animal species diversity in the forests. We studied the beetle (Coleoptera) fauna of four forest site types in northern Finland: in spruce mires, herb rich, mesic and sub-xeric forests. We sampled beetles in 32 study sites with five window and five pitfall traps in each. We describe the species abundance and diversity patterns within and among forest types and relate these patterns to structural components of the forests. The volume of decaying wood varied from 14 to 93 m³ ha⁻¹ among sampling sites. The total beetle catch consisted of 100 333 individuals and 435 species. The beetle species richness did not vary according to site fertility but the number of specimens increased with increasing fertility in heath forest sites. The richness of beetle species correlated only weakly with any of the stand structure characteristics at the stand level. Nevertheless, the detrended correspondence analysis (DCA) indicated that different beetle assemblages are characteristic of different forest types. The high level of beta-diversity in beetles among forest types indicates that focusing exclusively on, for example, key-biotopes (presumed biodiversity hotspots) when selecting areas to be set aside would result in a situation where a large proportion of species, even of the rare and threatened ones, is not included in this network of protected areas. This suggests that the complementary set of different forest types may be the best general strategy to maintain the overall beetle species diversity in boreal forests.     

Cloud forest dynamics in the Mexican neotropics during the last 1300 years

Key questions for understanding the resilience and variability of Mexican Neotropical cloud forest assemblages in current and future climate change include: How have human disturbances and climate change affected the dynamics of the cloud forest assemblage? What are the predominant processes responsible for its present day composition and distribution? Are the current conservation strategies for the cloud forest in accordance with preserving its natural variability through time? In this study, the temporal dynamics of the cloud forest in west‐central Mexico over the last ～1300 years were reconstructed using palaeoecological techniques. These included analyses of fossil pollen, microfossil charcoal, and sediment geochemistry. Results indicated that a cloud forest assemblage has been the predominant vegetation type in this region over the last ～1300 years. During this time, however, there have been changes in the vegetation with an apparent expansion of cloud forest from ～832 to 620 cal years bp and a decline from 1200 to 832 cal years bp . Climate change (intervals of aridity) and human disturbances through anthropogenic burning appear to have been the main factors influencing the dynamics of this cloud forest. The spatial heterogeneity reported for high‐altitude forests in this region, in concert with high beta diversity, appears to be a manifestation of the high temporal variability in species composition for these forests. Greater turnover in cloud forest taxa occurred during intervals of increased humidity and is probably representative of a higher temporal competition for resources among the cloud forest taxa. The present results support the current protection scheme for cloud forests in west‐central Mexico where areas are kept in exclusion zones to avoid timber extraction, grazing, and agriculture; this will maintain diversity within these forests, even if there are only a few individuals per species, and enable the forests to retain some resilience to current and future climate change.     

Secondary Rain Forests are not Havens for Reptile Species in Tropical Mexico

A widely accepted biodiversity crisis in the tropics has been recently challenged by claims that secondary forests will gradually restore biodiversity losses. This prediction was examined for the herpetofauna in Quintana Roo, Mexico. Quantitative sampling (108 transects) of reptiles was undertaken monthly (January–September 2004) along a vegetation gradient covering induced grasslands, and regrowth and primary rain forests. A total of 35 species was found, 14 being present in and five showing dependence on mature forests. Lizards contributed > 90 per cent of the individuals observed. Reptile abundance and snake species richness was highest in primary forests, even though the lower abundance and richness did not differ between regrowth forest and induced grasslands. Multivariate ordinations and ANOSIM tests displayed clear differences in assemblage structure among vegetation types, mainly caused by contrasting abundances of lizard species having distinctive arboreal or terrestrial habits. There was no evidence that snake assemblages differed between secondary forests and induced grasslands. Microhabitat availability had a key role in shaping species composition through the vegetation gradient. Our results dismiss the hypothesis that secondary forests can act as reservoirs of primary forest reptile diversity on the basis that many taxa depend largely on habitat quality and have specialized life‐history traits, and that biological succession does not guarantee the recovery of assemblage complexity.     

Liana communities exhibit different species composition,diversity and community structure across forest types in the Congo Basin

Lianas are poorly characterized for central African forests. We quantify variation in liana composition, diversity and community structure in different forest types in the Yangambi Man and Biosphere Reserve, Democratic Republic of Congo. These attributes of liana assemblages were examined in 12 1-ha plots, randomly demarcated within regrowth forest, old growth monodominant forest, old growth mixed forest and old growth edge forest. Using a combination of multivariate and univariate community analyses, we visualize the patterns of these liana assemblage attributes and/or test for their significant differences across forest types. The combined 12 1-ha area contains 2,638 lianas (≥2 cm diameter) representing 105 species, 49 genera and 22 families. Liana species composition differed significantly across forest types. Taxonomic diversity was higher in old growth mixed forests compared to old growth monodominant and regrowth forests. Trait diversity was higher than expected in the regrowth forest as opposed to the rest of forest types. Similarly, the regrowth forest differed from the rest of forest types in the pattern of liana species ecological traits and diameter frequency distribution. The regrowth forest was also less densely populated in lianas and had lower liana total basal area than the rest of forest types. We speculate that the mechanism of liana competitive exclusion by dominant tree species is mainly responsible for the lower liana species diversity in monodominant compared to mixed forests. We attribute variation in liana community structure between regrowth and old growth forests mostly to short development time of size hierarchies.     

Dead trees left in clear-cuts benefit saproxylic Coleoptera adapted to natural disturbances in boreal forest

Forest management alters the pattern of forest dynamics from that in natural conditions in the boreal region. In order to examine how certain forestry measures matching natural dynamics affect forest insects, we compared assemblages of saproxylic Coleoptera on dead, standing birch trunks left behind in eight clear-cut areas with corresponding assemblages in seven mature forests in southern and eastern Finland. We used trunk-window traps for sampling. Distinct beetle assemblages were associated with the different habitats. Median numbers of species or specimens caught did not differ between closed forests and clear-cuts, but individual beetle species occurred unevenly among the habitats. Several beetle species associated with open forest habitat, e.g. burned forests or storm-damage areas, including species regarded as threatened in Finland, were found almost exclusively, in clear-cuts. Correspondingly, a number of beetle species occurring frequently in closed forests were not found in clear-cuts. We conclude that dead trunks left in the clear-cut areas may host not only generalist saproxylic species but also many beetle species specialized to warm, sun-exposed environments, and such species may not be able to survive in closed forests. Management measures matching suppressed natural disturbances are found useful in preserving diversity in managed forests.     

Seasonal patterns of spatial variation in understory bird assemblages across a mosaic of flooded and unflooded Amazonian forests

We examined seasonal patterns of spatial variation in understory bird assemblages across a mosaic of upland and floodplain forests in central Amazonia, where variation in flooding patterns and floodwater nutrient load shapes a marked spatial heterogeneity in forest structure and composition. Despite great differences in productivity due to flooding by either nutrient-rich “white waters” (várzea) or nutrient-poor “black waters” (igapó), bird assemblages in the two floodplain forest types were relatively similar, showing lower abundances than adjacent upland forests (terra firme) and sharing a set of species that were absent or scarce elsewhere. Species that breed in pensile nests overhanging water were abundant in floodplain forests, whereas species that feed on the ground were generally scarce. Flooding affected assemblage dynamics in floodplain forests, with some influx of ground-dwelling species such as ant-following birds from adjacent upland during the low-water season, and the occupation by riverine and aquatic species such as kingfishers during floods. Spatial configuration influenced the seasonal pattern of assemblage structuring, with movements from terra firme occurring primarily to adjacent igapó forests. No such influx was detected in várzea forests that were farther from terra firme and isolated by wide river channels. Results support the view that habitat heterogeneity created by flooding strongly contributes to maintain diverse vertebrate assemblages in Amazonia forest landscapes, even in the case of largely sedentary species such as understory forest birds. Including both upland and floodplain forests in Amazonia reserves may thus be essential to preserve bird diversity at the landscape scale.     

The effects of habitat parameters and forest age on the ground dwelling spiders of lowland poplar forests (Hungary)

Forest management has highly modified the structure of the European forests. Harvesting and post-harvest regeneration leads to a simplified forest structure. Our main objective was to detect the effects of habitat structure and forest age on the ground-dwelling spider diversity and assemblage composition of poplar forests at the Hungarian Great Plain. Our results demonstrate that the rarefaction diversity and the number of forest specialists closely correlated with the structural parameters of the forest floor, however, the age and canopy closure did not influence these parameters. According to redundancy analysis, the composition of spider assemblages was determined solely by habitat structure, with habitat structure having a major effect on the species composition and diversity of spider assemblages. A direct effect of forest age on the spider assemblages was not detected, due to the presence of different habitat types in the surrounding landscape, which may serve as suitable habitats for source-populations of spiders with different habitat requirements. Our results highlight the importance structural complexity of forests for maintaining forest spider diversity and preserving the regional species pool of spiders.