Effects of Clearfell Harvesting on Lucanid Beetles (Coleoptera: Lucanidae) in Wet and Dry Sclerophyll Forests in Tasmania

The effects of commercial forestry harvest and regeneration practices (clearfelling and slash-burning) on the lucanid fauna of the wet sclerophyll forests of southern Tasmania and the dry sclerophyll forests of eastern Tasmania were examined using pitfall catches. Lucanids are saproxylic beetles, dependent on dead, moribund and decaying wood. Samples taken from old-growth forest and from a chronosequence of sites regenerating after logging, in each forest type, were used to compare the species richness and abundance of the lucanid assemblages. In both forest types, species richness and abundance was highest in the youngest regeneration sites (1–3 year), reflecting the species richness of the original and adjacent unlogged forest, lowest in the older (20–25 year) sites, and variable in the old-growth sites. TWINSPAN cluster analysis showed no clear distinction between regeneration and old-growth forest. The post-harvest slash and stump residue provided an important refugium and initial habitat, but our research indicates that some species may not maintain populations in the long term. Our results suggest that most species of lucanids will find a continuous supply of suitable habitat only in old-growth forests; and such species may become less common as clearfell harvesting leads to a replacement of heterogeneous old-growth forest with single-aged monospecific stands. Continuity of supply of wood in all decay stages, the maintenance of sufficient source areas, and biological connectivity between old-growth stands to enable dispersal, are all likely to be essential to maintain lucanid beetle community integrity. If similar principles apply to other saproxylic species of invertebrate, then clearfelling and slash-burning may cause a gradual extinction of an important element of the forest biota.     

Neotropical moth assemblages degrade due to oil palm expansion

Oil palm is one of the most rapidly expanding crops throughout the tropics, yet little is known about its impacts on Neotropical invertebrate biodiversity. Responses of insect assemblages to land conversion may substantially vary among taxa. We assessed geometrid and arctiine moth assemblages in a Costa Rican human dominated landscape, where oil palm plantations are now the second most common land cover. Moths were sampled during 6 months with automatic traps in the interior and margin of old-growth forests, young secondary forests and oil palm plantations in a 30 km² area. Our results show that richness and diversity of both taxa were severely reduced in oil palm compared to all other habitats. Geometrid abundance was highest in forest interiors and lowest in oil palm, while arctiine numbers did not differ between habitats. Dominance was highest in oil palm plantations, where one arctiine species and one geometrid species accounted for over 40% of total abundance in each of their respective taxa. Species composition was distinct in oil palm and forest interior sites, and depicted a gradient of habitat disturbance in ordination space that was strongly related to vegetation diversity and structure. This study demonstrates that oil palm plantations are not a suitable habitat for these moth taxa. Whilst some arctiine species seem adapted to disturbed habitats, geometrids were more dependent on old-growth forests, showing higher bioindicator potential. In the face of accelerated oil palm expansion, conservation strategies should focus on protecting old-growth forest remnants, as well as increasing species diversity and structural complexity of degraded habitats.     

Forest Age Influences In-stream Ecosystem Processes in Northeastern US

A disturbance or natural event in forested streams that alter available light can have potential consequences for nutrient dynamics and primary producers in streams. In this study, we address how functional processes (primary production and nutrient uptake) in stream ecosystems respond to changes in forest canopy structure. We focus on differences in incoming irradiance, nutrient uptake (NO₃, NH₄, and PO₄) and open-channel metabolism seasonally in 13 forested streams that drain forests with different canopy structures (10 to >300 years old) in the northeastern United States. Light irradiance was related to forest age in a U-shaped pattern, with light being the greatest in both young open forests (<50 years old) and older growth forests (>245 years old), whereas the darkest conditions were found in the secondary growth middle-aged forests (80–158 years old). Streams that had adjacent open or old-growth riparian forest had similar conditions with greater standing stock biofilm biomass (chl a), and elevated ER in October compared to streams with middle-aged riparian forests. Compared to all sites, streams with old-growth riparian forest had the greatest in-stream primary production rates (GPP) and elevated background nutrient concentrations, and to a lesser degree, increased nutrient retention and uptake (V _f). Streams draining older forests tended to be more productive and retentive than middle-aged forests, likely due to increased light availability and the age and structure of surrounding forest canopies. Middle-aged forests had the least variation in response variables compared to streams in young and old-growth riparian forests, likely a result of uniform canopy conditions. As the structure of widespread middle-aged forests in NE US is altered by loss of specific tree species, climate change, and/or human activity, it will impact in-stream production and nutrient dynamics and may ultimately alter nutrient loading in downstream catchments.     

Is microclimate-driven turnover of dung beetle assemblage structure in regenerating coastal vegetation a precursor to re-establishment of a forest fauna?

We questioned the capability of post-mining rehabilitation and successional changes in coastal vegetation to achieve restoration of dune forest, dung beetle assemblages in the Maputaland Centre of Endemism, South Africa. A repeat 2010 study of structural turnover between dung beetle assemblages across a 33 year successional sere of rehabilitating vegetation and old-growth forest (>73 years) produced comparable results to an earlier study across the 23 year chronosequence of 2000. Despite overlap, three structural patterns along the 33 year chronosequence were associated with specific stages of vegetation succession and their characteristic microclimates as in 2000. Although species biased to unshaded habitat dominated the earliest succession, there was rapid re-establishment of dominance by shade-associated forest species. In concert with progression from unshaded, post-mining vegetation to strongly shaded, early successional, Acacia shrub-woodland, there was an initial increase in similarity of the dung beetle fauna (species-poor, low abundance) to that in strongly-shaded forest (also species-poor, low abundance). However, in concert with decreasing shade cover in late successional woodland, the dung beetle fauna became species-rich with high abundance so that the early successional trajectory of increasing similarity to forest fauna either levelled off to a plateau (species in 2000; abundance in 2010) or declined (species in 2010, abundance in 2000). It remains to be seen if gaps forming in the oldest Acacia woodland permit forest tree saplings of the exposed understorey to recreate a forest canopy that would be tracked by dung beetles to re-establish a typically species-poor, deep shade, forest assemblage with low abundance.     

Changes in liana community structure and functional traits along a chronosequence of selective logging in a moist semi-deciduous forest in Ghana

ABSTRACT

Background: Lianas are an important component of tropical forests that respond to logging disturbance. Determining liana response to selective logging chronosequence is important for understanding long-term logging effects on lianas and tropical forests.

Aims: Our objective was to quantify the response of liana communities to selective logging chronosequence in a moist semi-deciduous forest in Ghana.

Methods: Liana community characteristics were determined in ten 40 m × 40 m plots randomly and homogenously distributed in each of four selectively logged forest stands that had been logged 2, 14, 40 and 68 years before the surveys and in an old-growth forest stand (ca. >200 years).

Results: Liana species composition differed significantly among the forest stands, as a function of logging time span, while species richness fluctuated along the chronosequence. The abundance of liana communities and of reproductive and climbing guilds was lower in the logged forests than in the old-growth forest. The ratio of liana abundance and basal area to those of trees was similar in the logged forests, but significantly lower than those in the old-growth forest.

Conclusions: Logging impacts on liana community structure and functional traits were largely evident, though no clear chronosequence trends were recorded, except for species composition.     

Disturbance and diversity of wood-inhabiting fungi: effects of canopy gaps and downed woody debris

Experimental canopy gap formation and additions of coarse woody debris (CWD) are techniques intended to mimic the disturbance regime and accelerate the development of northern hardwood forests. The effects of these techniques on biodiversity and ecosystem functioning were investigated by surveying the abundance and diversity of wood-inhabiting fungi in six treatments: (i) unharvested control, (ii) control + fenced to exclude deer, (iii) gap creation + fenced to exclude deer, (iv) gap creation, (v) gap creation + CWD addition, and (vi) CWD addition under closed-canopy. A total of 1,885 fungal occurrences (polyporoid and corticoid fruiting bodies) representing 130 species were recorded on 11 tree species, with eight fungal species accounting for 52 % of all observations. A linear mixed model demonstrated significant differences in the abundance and diversity of wood-inhabiting fungi by treatment, with the gap creation + CWD addition treatment supporting the highest abundance and richness of fungal species. Non-metric multidimensional scaling demonstrated that stumps, sugar maple substrates, medium (20 to <25 cm) and large-diameter (>40 cm) substrates most strongly influenced fungal species occurrences. Rarefaction curves indicated that smaller diameter substrates (<20 cm) supported a rich fungal community, yet substrates in the largest diameter class (>40 cm) supported nearly 25 % of all fungal species detected. Rarefaction curves also highlighted the importance of well-decayed substrates and minor host tree species. A subset of fungal species was significantly more abundant in gap treatments. The results indicate that wood-inhabiting fungi are responsive to forest management intended to promote the structural attributes of old-growth northern hardwood forests.     

Hoverfly (syrphidae) communities respond to varying structural retention after harvesting in canadian peatland black spruce forests

Variable retention harvesting (VRH), in which trees are removed at variable intensity and spatial configuration across the landscape, retains greater forest structural heterogeneity than traditional clear-cut harvesting and is being recommended as an alternative for sustainable management of the boreal forest. Little is known about its effects on forest fauna; thus, we studied the influence of one type of VRH (harvesting with advanced regeneration [HARP]) on the Syrphidae (Diptera) community in northern Ontario forests of peatland black spruce (Picea mariana). We examined the effects of varying structural retention (from unharvested through partial retention to clear-cut) on syrphid species richness and abundance, and abundance of functional assemblages. Greater species richness and population abundances were found generally in harvested than in unharvested forests. Overall species richness and the abundance of four species (Platycheirus rosarum, Toxomerus marginatus, Xylota annulifera, and X. tuberculata) and larval predators were all higher in both clear-cut sites and those with structural retention than in unharvested sites. Similarly, overall species richness and the abundance of nine species were higher in clear-cut than in unharvested sites. Species responses are discussed in an ecological context. Differences among the levels of forest retention harvesting were relatively minor compared with those of the clear-cut and unharvested area, suggesting that local habitat characteristics may play a more important role in determining the syrphid community than the landscape configuration. However, a landscape level effect was evident, suggesting that syrphids may be useful in reflecting changes in stand structure at the landscape scale.     

Edaphic beetle (Insecta: Coleoptera) diversity over a forest-matrix gradient in a tropical rainforest

Species from natural communities show different capacities for moving across contrasting habitats, and they may gradually respond along the transition between forests and anthropogenic areas. Because beetles are effective bioindicators, we analyzed the Coleoptera assemblage structure in the transition between sugarcane matrices and forest fragment. The study was conducted in an Atlantic rainforest fragment and sugarcane matrices after 2 and 6 months of replantation. Beetles were sampled in linear transects that were 50, 100, and 200 m from the forest edge and toward both forest core and matrices. We analyzed beetle abundance, species richness and composition, and diversity numbers. The abundance and species richness were higher in the forest, and species richness was higher at the sampling site 100 m inside the forest than at the gradients within the sugarcane matrices. The species composition differed between the forest and matrices, but not between the matrices with different replantation ages. Alpha diversity based on the number of species was higher in the forest, and alpha diversity based on the Shannon index was higher in the forest and matrix after 6 months of replantation. Our results suggest that the sugarcane matrices, chiefly the matrix after 2 months of replantation, sustain an impoverished beetle assemblage when compared with the forest fragment. Despite the strong habitat distinction, the beetle fauna in the sugarcane matrices was not affected by the horizontal distance from the forest. Here, we have highlighted the importance of forest fragments embedded in harsh matrices for the maintenance of biodiversity.     

The value of the trackway system within a lowland plantation forest for ground-active spiders

European forest management guidelines include conservation and enhancement of biodiversity. Within plantation forestry, trackways provide contiguous permanent open-habitat with potential to enhance biodiversity. We examined the ground-active spider assemblage in the trackway network of Thetford Forest, Eastern England, the largest lowland conifer forest in the UK, created by afforestation of heathland and farmland. Results are relevant to other forests in heath regions across Europe. We used pitfall trapping to sample the spider assemblage of trackways within thicket-aged stands (n = 17), mature stands (n = 13) and heathland reference sites (n = 9). A total of 9,314 individuals of 71 species were recorded. Spider assemblages of the trackway network were distinct from those of the heathland reference sites; however, trackways were found to support specialist species associated with grass-heath habitats, including nationally scarce species. Richness of grass-heath species was similar for trackways in thicket-aged forest and heathland reference sites, although the abundance of individuals was three times greater in the reference sites. Trackways in mature stands had lower grass-heath species richness and abundance than both thicket trackways and heath reference sites. Wide trackways within thicket stands contained greater richness and abundance of specialist xeric species than narrower trackways. However, fewer xeric individuals were found in trackways compared to heathland reference sites. Either inferior habitat quality in trackways or poor dispersal ability of specialist xeric species may largely restrict these to relict areas of heathland. Targeted widening of trackways to allow permanent unshaded habitat and creating early successional stages by mechanical disturbance regimes could improve trackway suitability for specialist species, helping to restore connectivity networks for grass-heath biodiversity.     

Long-Term Impacts of Forest Ditching on Non-Aquatic Biodiversity: Conservation Perspectives for a Novel Ecosystem

Artificial drainage (ditching) is widely used to increase timber yield in northern forests. When the drainage systems are maintained, their environmental impacts are likely to accumulate over time and along accompanying management, notably after logging when new forest develops on decayed peat. Our study provides the first comprehensive documentation of long-term ditching impacts on terrestrial and arboreal biodiversity by comparing natural alder swamps and second-generation drained forests that have evolved from such swamps in Estonia. We explored species composition of four potentially drainage-sensitive taxonomic groups (vascular plants, bryophytes, lichens, and snails), abundance of species of conservation concern, and their relationships with stand structure in two-ha plots representing four management types (ranging from old growth to clearcut). We found that drainage affected plot-scale species richness only weakly but it profoundly changed assemblage composition. Bryophytes and lichens were the taxonomic groups that were most sensitive both to drainage and timber-harvesting; in closed stands they responded to changed microhabitat structure, notably impoverished tree diversity and dead-wood supply. As a result, natural old-growth plots were the most species-rich and hosted several specific species of conservation concern. Because the most influential structural changes are slow, drainage impacts may be long hidden. The results also indicated that even very old drained stands do not provide quality habitats for old-growth species of drier forest types. However, drained forests hosted many threatened species that were less site type specific, including early-successional vascular plants and snails on clearcuts and retention cuts, and bryophytes and lichens of successional and old forests. We conclude that three types of specific science-based management tools are needed to mitigate ditching effects on forest biodiversity: (i) silvicultural techniques to maintain stand structural complexity; (ii) context-dependent spatial analysis and planning of drained landscapes; and (iii) lists of focal species to monitor and guide ditching practices.     

林业活动和森林片断化对甲虫多样性的影响及保护对策

森林片断化是造成生物多样性丧失的主要原因之一,而林业活动是导致森林片断化的重要因素,同时也在森林恢复中起重要作用。本文从小尺度、局域尺度以及生物地理尺度（大尺度）3个生态尺度分析林业活动和森林片断化对甲虫多样性的影响。在小尺度下,林业活动能够通过改变森林生境或微生境的类型和特性而影响甲虫物种分布。在局域尺度下,林业活动（尤其是森林砍伐）往往能提高许多甲虫类群（如步甲）的物种丰富度（α多样性）,这主要与来自周围环境物种扩散以及保留了若干耐受新环境能力较强的森林物种有关;然而,对森林生境依赖性很强的特有种受到了森林片断化的负面影响,面临局域种群灭绝的危险。在生物地理尺度下,林业活动（伐木或森林恢复）使森林生境单一化、异质性降低,从而导致对森林生境变化敏感的物种种群数量降低甚至灭绝。基于以上结果,可以归纳出3个基本原则用于指导林业管理,既能保证林业经济收益,又能维持森林生物多样性。首先,保留大面积的原始森林作为特有种的栖息环境基地,为这些物种在将来森林恢复后重新定居提供资源;其次,由于保护区内原始森林面积有限,且所代表的生境类型有限,所以发展依据自然干扰模式的新伐木方法十分必要;最后,依据自然规律（如火灾）进行森林恢复和天然演替,避免森林的单一化,丰富森林生境类型。     

Contrasting the distribution of butterflies and termites in plantations and tropical forests

In the tropics vast areas of natural forests are being converted into plantations. The magnitude of the resulting loss in arthropod biodiversity and associated ecosystem services represents a significant topic of research. In this study we contrasted the abundance, species richness and faunal turnover of butterflies, resident butterflies (i.e., whose host plants were ascertained to occur in the habitats studied) and termites between small (average 4.3 ha) 20+ year old exotic plantations (teak and Terminalia), native plantations (Cedro espino), and an old growth forest in Panama. We used Pollard walks and manual search to quantify the abundance or occurrence of butterflies and termites, respectively. In 2014 we observed 4610 butterflies representing 266 species and 108 termite encounters (out of 160 quadrats) representing 15 species. Butterflies were more abundant and diverse in plantations than in the forest, whereas this pattern was opposite for resident butterflies and termites. There was marked faunal turnover between plantations and forest. We conclude that (a) the magnitude of faunal changes between forest and plantations is less drastic for termites than for butterflies; (b) resident butterfly species are more impacted by the conversion of forest to plantations than all butterflies, including transient species; and (c) species richness does not necessarily decrease in the series forest > native > exotic plantations. Whereas there are advantages of studying more tractable taxa such as butterflies, the responses of such taxa can be highly unrepresentative of other invertebrate groups responsible for different ecological services.     

Long-Term Effects of Forest Regrowth and Selective Logging on the Seed Bank of Tropical Forests in NE Costa Rica1.

To investigate long-term effects of land use on the soil seed bank, we compared the abundance/density, species richness, life form distribution, and species composition of seeds stored in the soil of four 15–20 yr-old second-growth stands, two old-growth stands, and two previously selectively-logged stands in the Caribbean lowlands of Costa Rica. Surface soil (10 cm deep, 4.7 cm diameter) was collected at 10 m intervals along three 120–160 m long transects in each stand (44–48 soil cores, 22–24 combined seed bank samples per site). Seed density was highest but variable in second-growth stands (8331–14535 seeds/m²), low and homogeneous in old-growth stands (2258–2659 seeds/m²), and intermediate and highly variable in selectively-logged stands (1165–6854 seeds/m²), which also had contrasting logging intensities. Species richness was strongly dependent on seed density, but showed less variation. Life form distribution did not differ statistically among or within land-use categories. In each stand, herbs-forbs, shrubs, and vines dominated the seed bank (> 75% of the species richness and abundance), whereas trees were a minor component (< 20% of the species richness and < 5% of the abundance) and were predominandy early successional. Shrubs and vines were most abundant in second-growth stands where regrowth vegetation was repeatedly cut before abandonment, whereas grasses and sedges were most abundant in the only forest stand that was completely surrounded by pastures. In terms of species composition, old-growth stands were more similar to selectively-logged stands than to second-growth stands, but across stands, selectively-logged forests were most distinct from the other two forest types. An inventory of the standing woody vegetation in each site showed little representation of the woody taxa found in the seed bank. We discuss these results in the context of the main factors that have been postulated to influence the abundance, life form, and species composition of tropical forest seed banks, and explore the role of the latter during intermediate phases of tropical forest succession and regeneration.     

Temporal changes in the breeding bird community caused by post-fire treatments after the Samcheok forest fire in Korea

The Samcheok forest fire of April 2000 was the biggest stand-replacing fire recorded in Korea, and led to the largest-scale salvage logging operation (performed until 2005) ever implemented. We investigated the effects of the treatments performed after the fire on the breeding bird community in 2002–2005 (the management period) and 2006–2008 (the post-management period). A total of 75 line transect surveys resulted in 660 detections of 54 species in undisturbed stands (CO), in burned and naturally restored stands (NI), and in burned and logged stands (IT). Four species (Parus major, Aegithalos caudatus, Dendrocopos kizuki, and Parus ater) were identified as indicator species in CO which showed no temporal changes in bird communities and habitat structure. Among the various stand treatments, the standardized species richness was highest in CO (11.6 ± 4.6 species/transect in 2002–2005, 12.1 ± 3.5 in 2006–2008), and this richness did not change over time. On the other hand, low richness was observed in NI (6.8 ± 2.6 in 2002–2005, 9.6 ± 2.3 in 2006–2008), and the lowest richness was seen in IT (5.0 ± 2.4 in 2002–2005, 6.1 ± 1.8 in 2006–2008), but both of these increased over time. Although the bird abundances in NI and IT were lower than those in CO (38.0 ± 27.7 birds/transect in 2002–2005, 31.3 ± 10.9 in 2006–2008), the abundances in NI (15.1 ± 8.6 in 2002–2005, 17.6 ± 11.4 in 2006–2008) and IT (11.7 ± 8.3 in 2002–2005, 10.0 ± 4.6 in 2006–2008) were not significantly different. There was no significant difference in abundance between time periods for any of the stand treatments. These results imply that NI (i.e., no salvage logging) allows greater bird richness but not abundance to be recovered compared to IT. No indicator species was consistently present in NI throughout the two time periods covered due to the rapid regrowth of vegetation, but four open-habitat dwellers (Falco tinnunculus, Phoenicurus auroreus, Emberiza cioides, and Sturnus cineraceus) colonized IT during the post-management period. The bird assemblage in IT, as assessed by canonical correspondence analysis, shifted to open habitats, while the avifauna in NI became similar to that in CO over time. While post-fire treatment can provide new colonization opportunities for open-habitat dwellers, the slow colonization process, the low species richness, and the low bird abundance observed in large areas of IT indicate that post-fire treatment using salvage logging inhibits the restoration of forest bird communities by producing a poorer breeding bird community that is very different from the original one. Based on these lessons from the response to the Samcheok forest fire, we suggest that preserving as much of the disturbed forest as possible is essential, and that the current approach to post-fire treatment—intensive salvage logging—needs to be revised to ensure the effective restoration of breeding bird communities in disturbed temperate pine forests.     

Are the assemblages of tree pollination modes being recovered by tropical forest restoration?

Questions

Do the assemblages of pollination modes in restored (tree plantings) and secondary (naturally regenerated) forests change in comparison to primary forests, and how do these assemblages relate to species turnover at regional scale?

Location

Southeast region of Brazil.

Methods

We classified tree species found in a total of 40 forest sites (18 primary, 11 restored, 11 secondary) according to pollination mode, based on the literature. We calculated and compared functional dissimilarity distances, amounts of species and accumulated abundance of pollination modes, and functional indices of richness and evenness between forest types.

Results

Functional dissimilarity distances were much smaller than species dissimilarity distances within forest types (mean <20%, >80%, respectively), indicating a small variation in pollination modes between sites. Functional indices of richness and evenness did not differ between forest types. However, significant changes were found in the species and abundance proportions of several pollination modes. Primary forests were characterized by the predominance of generalized insect‐pollinated species, followed by secondary proportions of bee, wind and moth pollination; other pollination modes were underrepresented. In restored forests, reductions were found in generalized insect, moth, wind, fly, pollen‐consuming insect and very‐small insect pollination, whereas the species pollinated by bees and bats more than doubled. Smaller changes were found among secondary forests, including reductions in moth, fly and fig‐wasp pollination, whereas there were incremental changes in bee, beetle, big animal and small insect pollination.

Conclusions

Our results indicate a rather stable assemblage of pollination modes and also high ecological redundancy among trees regardless of the species replacement at the regional scale. Major changes among restored forests are probably in response to larger disturbance effects and/or restoration practices conducted in these sites. In contrast, smaller changes among secondary forests could be in response to smaller disturbance effects and natural selection processes, and also seem to suggest that highly resilient degraded areas are more likely to recuperate their functional diversity through natural regeneration alone. In both cases, however, efforts to recover such patterns should be encouraged to avoid possible negative effects in plant–pollinator interactions.     

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.     

Richness and Density of Birds in Timber <Emphasis Type="Italic">Nothofagus pumilio</Emphasis> Forests and their Unproductive Associated Environments

Research on forest management impact focuses mainly on timber stands, and leaves out the unproductive forest environments. These stands are spatially mixed with timber forests. The objective was to evaluate richness and density of birds in timber Nothofagus pumilio forests and their unproductive associated environments, and discuss forest management implications. These stands showed significant differences in their forest structure, which generate a great variety of ecological environments. A total of 1881 individuals belonging to 30 bird species were observed during the sampling, in spring and summer seasons. These species were mainly migratory and insectivores, Passeriforms being the most important group. From 12 to 17 birds/ha were found, which varied with the forest environments and seasons. Timber stands of Nothofagus pumilio support a low number of bird species. Most of them are opportunistic and a few prefer these woods over other forested or afforested areas. Low bird density and richness characterize these austral forests, which share their diversity with a high variety of ecosystems along Patagonia. Timber N. pumilio forests has a marginal value for bird species conservation, considering its richness, density and the percentage of this forest in the total forested landscape of Tierra del Fuego (Argentina).     

Establishment of laurel forest vegetation in adjacent secondary forest in central Japan

Distributions of lucidophyllous species are limited due to the fragmentation of laurel forest. On Komayama Hill in central Japan, we evaluated the colonization of typical lucidophyllous vascular plants from a 350-year-old laurel forest into adjacent abandoned secondary forest for conservation and restoration purposes. A total of 14 consecutive subplots were established along the vegetation border between the two forests (length, 30 m; width, 5 m), extending 70 m into the secondary forest; 18 quadrats of old-growth forest were surveyed. Edge effects of old-growth forest were found to play an important role in re-establishing lucidophyllous saplings and seedlings in the secondary forest. In particular, the abundances of the four dominant canopy species of the old-growth forest significantly decreased with increasing distance. Hence, they are expected to colonize further into the secondary forest and, ultimately, to dominate the canopy. However, the number of lucidophyllous species did not change with distance. Species such as Ficus nipponica, Damnacanthus indicus, Ilex integra, and Lemmaphyllum microphyllum were near-completely or completely limited to the old-growth forest. They are known to be negatively affected by forest fragmentation and were observed to be struggling to colonize the exterior of the old-growth forest even after 60 years of abandonment. Their absence highlighted the limited colonization capacities of some old-growth forest species and underlined the time required for habitat restoration following human disturbance. We conclude that it is important to consider the population dynamics of dominant canopy species and the colonization of these interior species when assessing the habitat expansion of lucidophyllous species and hence the restoration of degraded lands.     

Slash harvesting does not undermine beetle diversity on small clear-cuts containing sufficient legacies

Logging residues (slash) constitute an increasingly important source of renewable energy in forested countries, but their intensive extraction can reduce biodiversity. Important research issues include the mitigation potential of reduced logging and slash extraction levels, and their feasibility in production forestry. We performed a comparative study on beetle assemblages in relation to slash extraction practices in Estonia, where silviculture retains higher deadwood amounts than in intensive forestry systems, slash extraction level is ca. 50 %, and final fellings retain at least 5 % of the standing stock. We sampled beetles using flight-interception traps on six pairs of retention cut sites (one conventional and one slash-harvested; average size ca. 2 ha; in three forest site-types). The material comprised 11,948 beetle specimens identified to species level (500 species). Species of conservation concern occurred regularly in all sites, while a total of 18 putative pest species comprised only ca. 3 % of individuals in both treatments. There were no clear influences of slash extraction on species richness, abundance or assemblage composition. The main gradients in the assemblage composition were trapping season and site type; the latter co-varying with tree-species composition and deadwood volumes. We conclude that slash harvesting that retains (depending on forest type) 5–25 m³ ha^?1 of coarse deadwood and 10–35 m³ ha^?1 of fine deadwood neither reduces beetle diversity (at least of highly mobile species in the short term) nor affects pest outbreaks in our study system. To sustain beetle diversity, sufficient deadwood legacies should be supplemented with live-tree retention for a continuous deadwood supply during post-harvest succession.     

Environment heterogeneity and seasonal effects in ground-dwelling ant (Hymenoptera: Formicidae) assemblages in the Parque Estadual do Rio Doce, MG, Brazil

This work aimed to explore the response of ant species assemblage to contrasting types of forests in a semideciduous stationary rainforest, in the Parque Estadual do Rio Doce, South Eastern Brazil. We compared antropomorphic borders of this park and natural ecotones, such as lake margins continuous with forests, as well as preserved forests far from ecotones. We investigated whether ground-dwelling ant species richness, abundance and composition would change according to forest types and ecotones. We expected greater species richness in interior tall forest, compared with low forest or ecotone habitats. In addition, we tested the effect of climate seasonality on ant assemblages found in each studied vegetation type. Each forest type was surveyed based on a minimum transect sampling unit of 150 m long summing up 30 pit-falls per unit. Two sampling events, one in dry season (September of 2001) and another in the rainy season (January of 2002) were performed. For both seasons, tall forest presented greater total number of ant species, however lower mean ant species and abundance per trap than other forest types, thus corroborating the prediction that ecotones might present high alpha diversity. Mean species richness and abundance did not differ between interior low forest and lake edge, or between these habitats and reserve border. In general, species composition were not clearly defined by forest types. Results here found suggest that species loss or community dominance by generalist species, eventually due to deforestation, is probably a much greater problem than previously thought. However, to understand patterns of insect species diversity and distribution in tropical ecosystem should be taken in account much more comprehensive, spatially explicit sampling designs.