Area, shape and isolation of tropical forest fragments: effects on tree species diversity and implications for conservation

Aim To quantify the influences of forest area, shape and isolation on tree species diversity in Ghana and to compare their significance with the influences of climate (average annual rainfall) and disturbance (fire burn, logging, agriculture). Location The forest zone of southern Ghana, West Africa (between 5 and 8° N). Methods For twenty‐two forest fragments (1) bivariate regression analyses of tree species diversity (number and composition) were employed with forest spatial geometry, climate and disturbance variables. (2) Multivariate regression analyses of tree species number and all seven environmental variables were used to determine the variability in tree species number that could be accounted for by these environmental variables. Results Forest area, shape and isolation accounted for sharply decreasing proportions of variability in tree species diversity. Large forest fragments contained the greatest numbers of tree species and the highest proportions of rare tree species; irregular fragments had high proportions of regenerating, light‐demanding pioneers and mature, animal‐dispersed species and isolated fragments were floristically similar to less isolated fragments. Fire burn and average annual rainfall accounted for small, but nevertheless significant, proportions of variability in tree species diversity. Logging and agriculture were non‐significant variables. Main conclusions (1) Forest area is the most important consideration when planning tropical forest reserves. (2) Management of disturbance should take priority over management of forest shape if higher levels of tree diversity and species quality are to be maintained. (3) If new reserves are to be designated, they should be located within different climatic zones in order to capture a large fraction of the regional biota. (4) Biogeographers have an important role to play in formulating and testing hypotheses at a broad spatial scale and ultimately, informing conservation management within the tropical biome.     

The roles of rivers and Pleistocene refugia in shaping genetic diversity in Praomys misonnei in tropical Africa

Aim This study aims to elucidate the phylogeography of the murid rodent Praomys misonnei and to document whether or not rain forest refugia and rivers structure patterns of diversity within this species. Location Tropical Africa, from Ghana to Kenya. Methods Patterns of genetic structure and signatures of population history (cytochrome b gene) were assessed in a survey of 229 individuals from 54 localities. Using maximum likelihood, Bayesian, network and genetic structure analyses, we inferred intra‐specific relationships and tested hypotheses for historical patterns of gene flow within P. misonnei. Results Our phylogenetic analyses reveal a strong phylogeographical structure. We identified four major geographical clades within P. misonnei: one clade in Ghana and Benin, a Nigerian clade, a West Central African clade and a Central and East African clade. Several subclades were identified within these four major clades. A signal of population expansion was detected in most clades or subclades. Coalescence within all of the major clades of P. misonnei occurred during the Middle Pleistocene and/or the beginning of Late Pleistocene. Main conclusions Our results suggest a role for both Pleistocene refugia and rivers in structuring genetic diversity in P. misonnei. This forest‐dwelling rodent may have been isolated in a number of forest fragments during arid periods and expanded its range during wetter periods. Potential forest refugia may have been localized in Benin–Ghana, south‐western Cameroon, southern Gabon, northern Gabon and eastern Democratic Republic of Congo–western Uganda. The Niger and/or the Cross Rivers, the Oubangui‐Congo, Sanaga, Ogooue and/or Ivindo Rivers probably stopped the re‐expansion of the species from relict areas.     

Spatial and temporal changes in bird assemblages in forest fragments in an eastern Amazonian savannah

We investigated the effects of forest fragmentation on bird assemblages in an Amazonian savannah landscape with forest fragments that have been isolated for more than 100 years. The study was conducted in areas surrounding the village of Alter do Chão (2°31′S, 55°00′W), Santarém, Brazil. Bird surveys and measurements of tree density were undertaken in 25 areas, with 19 plots in forest fragments of different sizes and six in an area of continuous forest. Data on forest‐fragment size, perimeter, and isolation were obtained from a georeferenced satellite image. Variation in number of bird species recorded per plot was not related to vegetation structure (tree density). The number of bird species recorded per plot increased significantly only with fragment area, but was not influenced by fragment shape or degree of isolation, even when considering species from the savannah matrix in the analysis. Fragments had fewer rare species. Multivariate ordination analyses (multiple dimensional scaling, [MDS]) indicated that bird species composition changed along a gradient from small to large forest fragments and continuous‐forest areas. In the Amazonian savannah landscapes of Alter do Chão, the organization and composition of bird assemblages in forest fragments are affected by local long‐term forest‐fragmentation processes. Differences in the number of bird species recorded per plot and assemblage composition between forest fragments and continuous forest were not influenced by forest structure, suggesting that the observed patterns in species composition result from the effects of fragmentation per se rather than from preexisting differences in vegetation structure between sites. Nevertheless, despite their long history of isolation, the forest fragments still preserve a large proportion (on average 80%) of the avifauna found in continuous‐forest areas. The fragments at Alter do Chão are surrounded by natural (rather than planted) grassland, with many trees in the savannah matrix and the landscape has vast areas covered by forest, which may have helped to ameliorate the influences of forest fragmentation.     

Assessing the Success of Restoration Plantings in a Temperate New Zealand Forest

The success of restoration plantings in restoring indigenous forest vascular plant and ground invertebrate biodiversity was assessed on previously grass-covered sites in the eastern South Island, New Zealand. The composition and structure of grassland, three different aged restoration plantings (12, 30, and 35 years old), a naturally regenerating forest (100 years old), and a remnant of the original old-growth forest of the area were measured. The restoration plantings are dominated by the native tree Olearia paniculata, which is not indigenous to the study area. Despite this, indigenous forest invertebrate and plant species are present in all three restoration sites and with increasing age the restoration sites become compositionally more similar to the naturally regenerating and mature forest sites. In particular the regenerating vegetation of the restoration sites is very similar floristically to the regenerating vegetation of the naturally regenerating and mature forest sites, despite marked differences in the current canopy vegetation reflecting the presence of the planted O. paniculata. The presence of regeneration in all three restoration sites indicates that the functional processes that initiate regeneration, such as dispersal, are present. The majority of regenerating tree species (71%) are bird dispersed and it is clear that birds play an important role in the recolonization of plant species at these sites despite the absence of edible fruit attractive to frugivorous birds on O. paniculata, a wind-dispersed species. The strong correlations between plant and invertebrate community composition and study-site age (r = 0.80, ?0.24, ?0.68 for plants, beetles, and spiders, respectively) suggest that the restoration site plant and invertebrate communities are undergoing change in the direction of the naturally regenerating and mature forest communities. Without restoration, colonization of grassland by forest plants is very slow in the study area and the restoration plantings studied here have been successful because they have considerably accelerated the return to forest at these sites.     

The relative importance of local, regional and historical factors determining the distribution of plants in fragmented riverine forests: an emergent group approach

Aim To investigate how local, regional and historical factors shape the herbaceous plant communities in fragmented riverine forests, and how the community composition and species richness of these fragments is related to the interplay between the environmental factors and specific plant life‐trait combinations. Location Riverine forest fragments in the Grand‐duché de Luxembourg. Methods Forest fragments were surveyed for their abundance in herbaceous plant species. All plant species where clustered into Emergent Groups (EG) by means of a formal classification based on 14 life‐history traits. Within each EG, the local, regional and historical factors were related to the community composition using partial Canonical Correspondence Analyses (pCCA) and to the species richness using Generalized Linear Models (GLMs). The EG colonization ability was characterized by means of logistic regressions. Results We defined and characterized seven EGs, among which three consisted of forest specialist species (barochorous perennials, short geophytes and zoochorous perennials), which exhibited specific life‐trait combinations: large and short‐lived seeds and/or vernal phenology. Differences in EG composition between forest fragments were mainly explained by local environmental factors such as soil productivity and pH. The richness of barochorous perennials and short geophytes was well predicted by the historical and regional factors. The colonization ability appeared very low for barochorous perennials and short geophytes. Main conclusions Local environmental conditions appear to drive the differentiation of the riverine forest plant communities owing to the specific habitat requirements of many forest species. Spatial and temporal forest discontinuities affect the richness of forest specialist species, due to dispersal and/or recruitment limitations. The emergent group approach enhances the understanding of the relative influence of local, regional and historical factors by distinguishing between forest specialists from generalists or ‘matrix’ species, which have a masking effect.     

Ecological outcomes of agroforests and restoration 15 years after planting

Large‐scale forest restoration relies on approaches that are cost‐effective and economically attractive to farmers, and in this context agroforestry systems may be a valuable option. Here, we compared ecological outcomes among (1) 12–15‐year‐old coffee agroforests established with several native shade trees, (2) 12–15‐year‐old high‐diversity restoration plantations, and (3) reference old‐growth forests, within a landscape restoration project in the Pontal do Paranapanema region, in the Atlantic Forest of southeastern Brazil. We compared the aboveground biomass, canopy cover, and abundance, richness, and composition of trees, and the regenerating saplings in the three forest types. In addition, we investigated the landscape drivers of natural regeneration in the restoration plantations and coffee agroforests. Reference forests had a higher abundance of trees and regenerating saplings, but had similar levels of species richness compared to coffee agroforests. High‐diversity agroforests and restoration plantations did not differ in tree abundance. However, compared to restoration plantations, agroforests showed higher abundance and species richness of regenerating saplings, a higher proportion of animal‐dispersed species, and higher canopy cover. The abundance of regenerating saplings declined with increasing density of coffee plants, thus indicating a potential trade‐off between productivity and ecological benefits. High‐diversity coffee agroforests provide a cost‐effective and ecologically viable alternative to high‐diversity native tree plantations for large‐scale forest restoration within agricultural landscapes managed by local communities, and should be included as part of the portfolio of reforestation options used to promote the global agenda on forest and landscape restoration.     

The Nature of Seedling Assemblages in a Fragmented Tropical Landscape: Implications for Forest Regeneration

Whether aging forest fragments are able to recover original assemblages or progressively move toward impoverished successional stages remains as an open question. This study tested the hypothesis that seedling assemblages in forest fragments differ from those across mature forest stands and examined to what extent the uncovered patterns supported the notion that edge‐affected habitats tend to support impoverished tree assemblages dominated by pioneer species. We contrasted a series of small forest remnants (3–91 ha) to old‐growth stands located in the largest (ca 3500 ha) and best preserved forest remnant in northeastern Brazil and found that tree seedling assemblages inhabiting forest fragments exhibited reduced species richness (up to 50%) at different spatial scales in comparison to seedling assemblages in mature forest and adult assemblages in both fragments and mature forest stands. Moreover, ordination analyses clearly segregated fragment seedling assemblages in taxonomic/functional terms and segregation correlated to the richness of pioneer species. Seedlings of pioneer species and those bearing medium‐sized seeds (0.6–1.5 cm) increased in fragments, whereas large‐seeded species (1.5–3.0 cm) were reduced by more than a half. Such a multiple‐scale replacement of the old‐growth flora by pioneers was also confirmed by an indicator species analysis and the resulting pioneer indicator species. Our results suggest that small forest fragments support impoverished and distorted seedling assemblages. This floristic/functional drift implies that forest remnants or edge‐affected habitats tend to be dominated by a small set of pioneer tree species rather than supporting a substantial portion of the old‐growth flora as do mature forest stands.     

Does selective logging change ground‐dwelling beetle assemblages in a subtropical broad‐leafed forest of China?

Selective logging with natural regeneration is advocated as a near‐to‐nature strategy and has been implemented in many forested systems during the last decades. However, the efficiency of such practices for the maintenance of forest species are poorly understood. We compared the species richness, abundance and composition of ground‐dwelling beetles between selectively logged and unlogged forests to evaluate the possible effects of selective logging in a subtropical broad‐leafed forest in southeastern China. Using pitfall traps, beetles were sampled in two naturally regenerating stands after clearcuts (ca. 50 years old, stem‐exclusion stage: selectively logged 20 years ago) and two mature stands (> 80 years old, understory re‐initiation stage: selectively logged 50 years ago) during 2009 and 2010. Overall, selective logging had no significant effects on total beetle richness and abundance, but saproxylic species group and some abundant forest species significantly decreased in abundance in selectively logged plots compared with unlogged plots in mature stands. Beetle assemblages showed significant differences between selectively logged and unlogged plots in mature stands. Some environmental characteristics associated with selective logging (e.g., logging strategy, stand age, and cover of shrub and moss layers) were the most important variables explaining beetle assemblage structure. Our results conclude that selective logging has no significant impacts on overall richness and abundance of ground‐dwelling beetles. However, the negative effects of selective logging on saproxylic species group and some unlogged forest specialists highlight the need for large intact forested areas for sustaining the existence of forest specialist beetles.     

Differences in seed rain composition in small and large fragments in the northeast Brazilian Atlantic Forest

Tropical forests are seriously threatened by fragmentation and habitat loss. The impact of fragment size and forest configuration on the composition of seed rain is insufficiently studied. For the present study, seed rain composition of small and large forest fragments (8–388 ha) was assessed in order to identify variations in seed abundance, species richness, seed size and dispersal mode. Seed rain was documented during a 1‐year period in three large and four small Atlantic Forest fragments that are isolated by a sugarcane matrix. Total seed rain included 20,518 seeds of 149 species of trees, shrubs, palms, lianas and herbs. Most species and seeds were animal‐dispersed. A significant difference in the proportion of seeds and species within different categories of seed size was found between small and large fragments. Small fragments received significantly more very small‐sized seeds (<0.3 cm) and less large‐seeded species (>1.5 cm) that were generally very rare, with only one species in small and eight in large fragments. We found a negative correlation between the inflow of small‐sized seeds and the percentage of forest cover. Species richness was lower in small than in large fragments, but the difference was not very pronounced. Given our results, we propose changing plant species pools through logging, tree mortality and a high inflow of pioneer species and lianas, especially in small forest fragments and areas with low forest cover. Connecting forest fragments through corridors and reforestation with local large‐seeded tree species may facilitate the maintenance of species diversity.     

Identifying forest‐obligate birds in tropical moist cloud forest of Andean Ecuador

ABSTRACT Large‐scale transformation of forested landscapes is a major factor in loss of biological diversity in the American tropics. Investigators examining the responses of species to deforestation rarely control for variation in the amount of forest relative to other habitats at the landscape‐level. Bellavista Reserve on the western slope of the Andes in Ecuador is located between similar‐sized areas of pristine, protected forest, and deforested landscapes. We used strip‐transect counts and mist netting to evaluate habitat use by passerine birds in a habitat mosaic consisting of abandoned pastures, forest edges, forest fragments, and large blocks of interior tropical montane cloud forest (TMCF). During 3600 net hours, we had 1476 captures, including 346 recaptures. Of 78 species captured in mist nets, 30 had sufficient counts for Poison Rate Regression (PRR) modeling (a statistical method for comparing counts). Twelve species (40%) had capture patterns indicative of an affinity for mature TMCF, and 6 species (20%) had significantly higher counts in degraded areas (forest edge, forest fragment, and regenerating pastures) than in interior TMCF. The remaining 40% showed no significant bias in detection among habitats. Combined with strip‐count data, our results suggest that about 38% of the 119 species sampled at the Bellavista Reserve occur primarily in mature TMCF, avoiding edges and early second‐growth forest. Populations of these species may be vulnerable to further loss, fragmentation, and degradation of TMCF and, as such, deserve additional study and a place on lists of species of conservation concern.     

Dung beetles in pasture landscapes of Central America: proliferation of synanthropogenic species and decline of forest specialists

This study examines the spread of synanthropogenic dung beetles (species favoured by human activities) in pasture landscapes in Central America, and evaluates the role of forest fragments and regenerating patches of native vegetation in maintaining beetle diversity. Pitfall trapping was carried out at nine locations in El Salvador and seven in Atlantic Nicaragua that included both pasture and remnant or regenerating native vegetation. More dung beetle species occurred in forest fragments than in pastures. Community composition differed considerably between forest fragments from El Salvador and Nicaragua with many species restricted to either the Caribbean or Pacific regions. In contrast, dung beetle community composition and structure were largely the same in the pastures of El Salvador and Nicaragua, regardless of region or original habitat-type, and were similar to published results from pastures in Mexico and elsewhere on the Isthmus. Very small patches of native shrubs and tree stands (<2.5 ha) maintained no forest specialists in Nicaragua, whereas, in El Salvador, some forest specialists occurred even in the smallest stands of trees (ca. 0.25 ha). The study indicates that the expansion of cattle pastures has caused a regional decline in dung beetle diversity. Forest fragments and small isolated patches of native trees and shrubs maintain some of the diversity of the original landscape but their conservation value for dung beetles will depend on the biogeographical history of the sites.     

Amphibian communities along a forest degradation gradient in an East African forest reserve

The amphibian communities in Africa's tropical forests are of global conservation importance, but disturbances derived from anthropological activities threaten to dismantle this irreplaceable diversity. We explored the impacts of forest degradation on the amphibian community in Mabira Central Forest Reserve, Uganda. We sampled amphibians from March to July of 2015 in plots that were positioned along a gradient of forest degradation. We conducted visual encounter surveys across three categories of forest degradation with six 300-m transects in each (four surveys per transect). From 216 h of surveyor effort, we detected 3563 individual frogs representing 30 species from eight families and 13 genera. Hyperoliidae was the most diverse family represented by 13 species in four genera. Hyperolius had the highest number of species (nine) followed by four genera each represented by three species (Phrynobatrachus, Pytchadena, Leptopelis, and Sclerophrys). Comparisons among plots along a gradient of forest degradation revealed differences in species richness, composition, and frequency of encounters. The regenerating and degraded forest plots were similar in species composition to each other and were dominated by mostly widespread, open-canopy species. Several forest-dependent species were recorded in both the regenerating and mature forest plots but were absent from the degraded plots. In the regenerating and mature forests, species presence was significantly associated with high canopy cover, high relative humidity, and dense leaf litter, whereas the microhabitat variables of high grass cover and high temperature were most influential in the degraded forests. Our study provides important data on an Afrotropical amphibian community and suggests that forest degradation has dramatically altered the habitat to the detriment of forest specialist species.     

Fragmentation and pre-existing species turnover determine land-snail assemblages of tropical rain forest

Aim The main aims of the study were: (1) to investigate the effect of fragment age in relation to other patch‐ and landscape‐scale measures of forest fragmentation, and (2) to assess the relative importance of fragmentation, habitat degradation (i.e. degradation caused by selective logging and past shifting cultivation) and putative pre‐existing species turnover in structuring current land‐snail assemblages. Location South‐western Sri Lanka. Methods The land‐snail fauna was sampled using standardized belt transects. Fifty‐seven transects were sampled in 21 lowland rain forest fragments (c. 1–33,000 ha). The spatial arrangement of fragments in the study area was explicitly considered in an effort to take into account the non‐random nature of fragmentation and degradation and the possibility that current species composition may reflect patterns of species turnover that existed prior to fragmentation. The data set of 57 land‐snail species and 28 environmental and spatial variables was analysed using canonical correspondence analysis and partial canonical correspondence analysis. Results Fragment age, mean shape complexity (i.e. a landscape‐scale measure of shape complexity), altitude, and the spatial variables x (longitude), y (latitude) and y² explained significant variation in land‐snail species composition. None of the three nominal variables quantifying habitat degradation was significantly correlated with variation in species composition. The independent effects of fragment age and mean shape complexity were similar. The combined effect of the spatial variables alone was larger than the independent effects of fragment age, mean shape complexity or altitude, but was of the same order of magnitude. The total variation explained by the spatial variables was comparable to the total non‐spatial variation accounted for by fragment age, mean shape complexity and altitude. Main conclusions Fragment age was found to be one of only two key determinants (the other was shape complexity at the landscape scale) driving fragmentation‐related changes in community composition. The influence of pre‐fragmentation patterns of species turnover on assemblage structure can be stronger than the effects of fragmentation measures, such as age, and may override the effects of forest degradation. Thus, strong patterns of pre‐existing turnover may potentially confound interpretation of the effects of forest fragmentation and degradation.     

Rehabilitation of Logged Rain Forests: Avifaunal Composition,Habitat Structure,and Implications for Biodiversity‐Friendly REDD+

The inclusion of carbon stock enhancements under the Reducing Emissions from Deforestation and Forest Degradation (REDD+) framework will likely drive a rapid increase in biosequestration projects that remove carbon from the atmosphere through rehabilitation of degraded primary rain forests. Such projects could also present an important opportunity to reverse losses of biodiversity from degraded rain forests, but concern has recently been expressed that management interventions to increase carbon stocks may conflict with biodiversity conservation. Focusing on a large‐scale rain forest rehabilitation project in northern Borneo, we examine: (i) how intensive rehabilitation of selectively logged forests affected patterns of bird community composition and (ii) whether changes in vegetation structure explain observed shifts in avian guild structure and species composition. Bird composition differed between unlogged, naturally regenerating logged, and rehabilitated logged habitats, with the avifauna of rehabilitated forest more similar to that of naturally regenerating forest. Crucially, rehabilitation did not adversely affect either those species that declined after logging or those species that are IUCN Red Listed. Rehabilitation reduced the prevalence of vines and shrubs within regenerating forest, and across all habitats, the abundance and species richness of all birds and of obligate frugivores were positively related to vine prevalence. In contrast, the abundance and richness of frugivore–insectivore generalists and of salliers were negatively related to vines, suggesting that avifaunal responses to forest rehabilitation were attributable to liberation cutting of vines. Management intervention to increase carbon stocks had little adverse effect on avian biodiversity and we therefore argue that rain forest rehabilitation should play a strong role in future REDD+ agreements.     

Secondary Succession and Indigenous Management in Semideciduous Forest Fallows of the Amazon Basin1

To the discussion on secondary succession in tropical forests, we bring data on three under‐addressed issues: understory as well as overstory changes, continuous as opposed to phase changes, and integration of forest succession with indigenous fallow management and plant uses. Changes in vegetation structure and species composition were analyzed in secondary forests following swidden agriculture in a semideciduous forest of Bolivian lowlands. Twenty‐eight fallows, stratified by four successional stages (early = 1–5 yr, intermediate = 6–10 yr, advanced = 12–20 yr, and older = 22–36 yr), and ten stands of mature forests were sampled. The overstory (plants ≥5 cm diameter at breast height [DBH]) was sampled using a 20 × 50 m plot and the understory (plants <5 cm DBH) in three nested 2 × 5 m subplots. Semistructured interviews provided information on fallow management. Canopy height, basal area, and liana density of the overstory increased with secondary forest age. The early stage had the lowest species density and diversity in the overstory, but the highest diversity in the understory. Species composition and abundance differentiated mature forests and early successional stage from other successional stages; however, species showed individualistic responses across the temporal gradient. A total of 123 of 280 species were useful with edible, medicinal, and construction plants being the most abundant for both over‐ and understories. Most of Los Gwarayo preferred mature forests for making new swidden, while fallows were valuable for crops, useful species, and regenerating timber species.     

Bryophyte species richness and composition in young forests regenerated after clear-cut logging versus after wildfire and spruce budworm outbreak

The disturbance regime in mixed-wood forests of eastern Canada is characterized by both natural disturbances including wildfires and insect outbreaks as well as forestry. The understanding of how understorey plant assemblages respond to different disturbances is mostly limited to short-term wildfire-logging comparisons of vascular plants. Here, we compare patterns of species richness and composition of four bryophyte guilds in young forests (approx. 40 years old) regenerating after clear-cut logging, wildfire, and spruce budworm outbreak. In addition, young forests were compared with mature spruce-fir dominated stands (approx. 90 years old). Although similar in overall species richness at the scale of 1,000 m² all young forest types were compositionally distinct with fewer species than mature forests. Stands developed after spruce budworm outbreaks had the highest canopy cover values and the highest surface area of coarse woody debris. These stands had similar numbers of woody debris species as mature forests and were closest to mature forests in species composition. Wildfire-disturbed sites were dominated by deciduous trees and a high number of treebase species. Finally, young managed forest had the highest number of forest floor bryophytes at the scale of 100 m² among the three young forest types, but was compositionally far from mature forests in their woody debris flora. In conclusion, young forests regenerating after natural disturbances are distinctly different from young forests regenerated after clear-cutting and if natural disturbances are eliminated certain species (e.g., epixylic and treebase species) might become more restricted to older stands in the landscape.     

Impacts of forest fragmentation on species composition and forest structure in the temperate landscape of southern Chile

Aim Few studies have explicitly examined the influence of spatial attributes of forest fragments when examining the impacts of fragmentation on woody species. The aim of this study was to assess the diverse impacts of fragmentation on forest habitats by integrating landscape‐level and species‐level approaches. Location The investigation was undertaken in temperate rain forests located in southern Chile. This ecosystem is characterized by high endemism and by intensive recent changes in land use. Method Measures of diversity, richness, species composition, forest structure and anthropogenic disturbances were related to spatial attributes of the landscape (size, shape, connectivity, isolation and interior forest area) of forest fragments using generalized linear models. A total of 63 sampling plots distributed in 51 forest fragments with different spatial attributes were sampled. Results Patch size was the most important attribute influencing different measures of species composition, stand structure and anthropogenic disturbances. The abundance of tree and shrub species associated with interior and edge habitats was significantly related to variation in patch size. Basal area, a measure of forest structure, significantly declined with decreasing patch size, suggesting that fragmentation is affecting successional processes in the remaining forests. Small patches also displayed a greater number of stumps, animal trails and cow pats, and lower values of canopy cover as a result of selective logging and livestock grazing in relatively accessible fragments. However, tree richness and β‐diversity of tree species were not significantly related to fragmentation. Main conclusions This study demonstrates that progressive fragmentation by logging and clearance is associated with dramatic changes in the structure and composition of the temperate forests in southern Chile. If this fragmentation process continues, the ability of the remnant forests to maintain their original biodiversity and ecological processes will be significantly reduced.     

Ectomycorrhizal colonization of naturally regenerating <Emphasis Type="Italic">Pinus sylvestris</Emphasis> L. seedlings growing in different micro-habitats in boreal forest

We investigated the species richness and composition of ectomycorrhizal (EM) fungi colonizing Pinus sylvestris L. seedlings naturally regenerating in boreal forest, in three different microhabitats: on forest ground, on decaying stumps, and within moss layer on erratic boulders. We tested the hypothesis that habitat differences would affect the composition of the EM community of regenerating pine seedlings. In total, 16 EM species were detected, from which none occurred on seedlings growing in all three microhabitats. Piloderma croceum and Cenococcum geophilum were common for seedlings growing in forest ground and on boulders, while Tricholoma aestuans and Suillus luteus were shared between seedlings growing on forest ground and decaying stumps. EM species richness and composition were strikingly different between seedlings regenerating in different microhabitats. Results are discussed as a function of dispersal and niche differentiation of EM fungi.     

The role of canopy gaps in the regeneration of coastal dune forest

In regenerating coastal dune forest, the canopy consists almost exclusively of a single species, Acacia karroo. When these trees die, they create large canopy gaps. If this promotes the persistence of pioneer species to the detriment of other forest species, then the end goal of a restored coastal dune forest may be unobtainable. We wished to ascertain whether tree species composition and richness differed significantly between canopy gaps and intact canopy, and across a gradient of gap sizes. In three known‐age regenerating coastal dune forest sites, we measured 146 gaps, the species responsible for gap creation, the species most likely to reach the canopy and the composition of adults, seedlings and saplings. We paired each gap with an adjacent plot of the same area that was entirely under intact canopy and sampled in the same way. Most species (15 of 23) had higher abundance in canopy gaps. The probability of self‐replacement was low for A. karroo even in the largest gaps. Despite this predominance of shade‐intolerant species, regenerating dune forest appears to be in the first phase of succession with ‘forest pioneers’ replacing the dominant canopy species. The nature of these species should lead to successful regeneration of dune forest.     

Edge disturbance drives liana abundance increase and alteration of liana–host tree interactions in tropical forest fragments

Closed‐canopy forests are being rapidly fragmented across much of the tropical world. Determining the impacts of fragmentation on ecological processes enables better forest management and improves species‐conservation outcomes. Lianas are an integral part of tropical forests but can have detrimental and potentially complex interactions with their host trees. These effects can include reduced tree growth and fecundity, elevated tree mortality, alterations in tree‐species composition, degradation of forest succession, and a substantial decline in forest carbon storage. We examined the individual impacts of fragmentation and edge effects (0–100‐m transect from edge to forest interior) on the liana community and liana–host tree interactions in rainforests of the Atherton Tableland in north Queensland, Australia. We compared the liana and tree community, the traits of liana‐infested trees, and determinants of the rates of tree infestation within five forest fragments (23–58 ha in area) and five nearby intact‐forest sites. Fragmented forests experienced considerable disturbance‐induced degradation at their edges, resulting in a significant increase in liana abundance. This effect penetrated to significantly greater depths in forest fragments than in intact forests. The composition of the liana community in terms of climbing guilds was significantly different between fragmented and intact forests, likely because forest edges had more small‐sized trees favoring particular liana guilds which preferentially use these for climbing trellises. Sites that had higher liana abundances also exhibited higher infestation rates of trees, as did sites with the largest lianas. However, large lianas were associated with low‐disturbance forest sites. Our study shows that edge disturbance of forest fragments significantly altered the abundance and community composition of lianas and their ecological relationships with trees, with liana impacts on trees being elevated in fragments relative to intact forests. Consequently, effective control of lianas in forest fragments requires management practices which directly focus on minimizing forest edge disturbance.