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Interspecific competition, environmental filtering, or spatial variation in productivity can contribute to positive or negative spatial covariance in the abundances of species across ensembles (i.e. groups of interacting species defined by geography, resource use, and taxonomy). In contrast, density compensation should give rise to a negative relationship between ecomorphological similarity and abundance of species within ensembles. We evaluated (1) whether positive or negative covariances characterized the pairwise relationships of 21 species of Congolese shrew, and (2) whether density compensation characterized the structure of each of 36 Congolese shrew ensembles, and did so based on the abundances or biomasses of species. In general, positive covariance is more common than negative covariance based on considerations of abundance or biomass, suggesting dominant roles for environmental filtering and productivity. Nonetheless, negative covariance is more common for ecomorphologically similar species, suggesting a dominant role for competition within functional groups. Effects of abundance or biomass compensation, via pairwise or diffuse competitive interactions, were detected less often than expected by chance, suggesting that interspecific competition is not the dominant mechanism structuring these ensembles. Effects of competition may be balanced by responses to variation in resource abundance among sites in a landscape or among niche spaces within sites. Future studies of compensatory effects should incorporate considerations of heterogeneity in the abundance and distribution of resources in ecological space to better isolate the effects of competition and resource abundance, which can have opposing effects on community structure. [ABSTRACT FROM AUTHOR]

The biota comprises all living organisms (bacteria, fungi, plants, animals) that inhabit a given area. Therefore, the objective of this paper was to evaluate the spatial distribution and status of biota habitats in the forest reserves of Omo and Ago-Owu in Ogun State, Oluwa in Ondo State, and Ife and Shaha in Osun State of southwestern Nigeria using appropriate standard techniques. The field surveys were conducted in relation to a 5 km × 5 km grid of cells across the target region. Twenty-three transects 5 km in length were created, and walks of 2.5 km from the boundary to the center of the grid cell enabled observation and data collection in these forest complexes. Mammals were detected at very low rates, especially in the Osun reserves. From the 23 transects totaling 115 km, only 140 mammals were encountered. Most large mammals, particularly elephants, are relatively abundant across much of the western Omo Forest. Hunters' reports showed that chimpanzees are still present in southern Shasha and in Oluwa Forests. Our assessment revealed that except for the 4.6 km² Strict Natural Biosphere Reserve in Omo, all the remaining natural forests have been heavily damaged by many years of intensive logging. However, if protected and given time, these forests can still regenerate. [ABSTRACT FROM AUTHOR]

The biota comprises all living organisms (bacteria, fungi, plants, animals) that inhabit a given area. Therefore, the objective of this paper was to evaluate the spatial distribution and status of biota habitats in the forest reserves of Omo and Ago-Owu in Ogun State, Oluwa in Ondo State, and Ife and Shaha in Osun State of southwestern Nigeria using appropriate standard techniques. The field surveys were conducted in relation to a 5 km × 5 km grid of cells across the target region. Twenty-three transects 5 km in length were created, and walks of 2.5 km from the boundary to the center of the grid cell enabled observation and data collection in these forest complexes. Mammals were detected at very low rates, especially in the Osun reserves. From the 23 transects totaling 115 km, only 140 mammals were encountered. Most large mammals, particularly elephants, are relatively abundant across much of the western Omo Forest. Hunters’ reports showed that chimpanzees are still present in southern Shasha and in Oluwa Forests. Our assessment revealed that except for the 4.6 km2 Strict Natural Biosphere Reserve in Omo, all the remaining natural forests have been heavily damaged by many years of intensive logging. However, if protected and given time, these forests can still regenerate.

Hopea reticulata Tardieu (Dipterocarpaceae) represents a critically endangered tree species primarily confined to the Ganza Ridge of Hainan Island, China, with a couple of additional records of populations in Thailand and Vietnam. Neither the species’ genetic diversity, which is essential for a species’ long-term survival in the face of changing climate and various biotic stresses, nor the demographic history, which directly affects genetic diversity, has been examined. In this study, we employed double-digest restriction site-associated sequencing to investigate the population structure and evolutionary history of H. reticulata on Hainan Island. Our analysis revealed that H. reticulata exhibits the lowest nucleotide diversity (π = 0.00091) when compared to other well-known endangered tree species in China that have been assessed using high-throughput sequencing data. Utilizing the software Stairway Plot 2 for demographic history inference, we identified a significant reduction in effective population size of H. reticulata, a result concordant with the species’ restricted geographic range and likely responsible for its low genetic diversity. Additionally, our research unveiled a weak genetic structure within geographically close H. reticulata populations, probably resulted from limited seed dispersal. These findings offer valuable insights into the conservation and management strategies required for the protection of H. reticulata on Hainan Island.

The functional space of an ecological community is not evenly filled by its species. Instead, it is usually divided into areas of high species density, where species with common combinations of functional traits are grouped into species rich clusters, while lower density areas are filled with species poor clusters or isolated species with uncommon or unique combinations of traits. Species whose functional traits differ from those of the rest of the community are expected to play distinct ecological roles and over-contribute to ecosystem functionality. Sampling methods used to characterize arthropod assemblages usually target subsets of the community and filter species based on their functional traits, reducing the probability of detecting species with uncommon combinations of functional traits. Consideration of these species is particularly important for characterizing the functional structure and resilience of ecological communities inhabiting threatened ecosystems such as lowland Amazonian rainforests, in which dung beetles play multiple ecological roles and are commonly used as ecological indicators. In this study, we characterize the functional structure of a diverse Amazonian dung beetle assemblage using five different sampling methods (dung- and carrion-baited pitfalls, dung-baited aerial traps, flight interception traps, and visual transects) and 18 different functional traits. Our main objective is to assess the suitability of these methods for the detection of the functional volume of the assemblage and of species with uncommon or unique combinations of functional traits that are expected to support vulnerable ecosystem functions. We found that, although dung-baited pitfalls (DPF) detected the highest species richness and proportion of the functional volume, they did not detect 30 species out of 103 and over 20% of the functional volume of the assemblage. The additional sampling methods captured more species with uncommon combinations of functional traits than expected by chance, some of which were trophic specialists not attracted to DPFs. The use of complementary sampling methods resulted in a better characterization of the functional structure of dung beetle communities inhabiting both terra firme and floodplain Amazonian rainforests and revealed functional resilience and rare species playing ecological roles overlooked by DPFs. The consideration of these species is of great importance given the threats that tropical rainforests face worldwide.

Biological invasions drive biodiversity loss and ecosystem change on tropical islands. However, we know little about the implications of species losses on the functional structure of both resident and novel communities. Herein, we examined the potential effect of a non-native palm species, Pinanga coronata, on the taxonomic and functional assemblages of understory plant species in a Fijian rainforest. We predicted that competition from this invasive species would lead to trait convergence according to the competitive hierarchy hypothesis. Using a trait-based approach, we sampled plant communities in 280 plots across a gradient of P. coronata densities. We measured five functional traits, including height and leaf traits related to nutrient acquisition. We found that an increase in P. coronata density is strongly correlated with a decrease in taxonomic diversity (i.e., about − 50% for species richness and − 33% for Shannon diversity index) and a decrease in functional richness. Community-weighted mean values of traits of resident species (i.e., excluding P. coronata) converged toward competitive strategies such as higher leaf nitrogen content (LNC), lower carbon-to-nitrogen (C:N) ratios and leaf dry matter content (LDMC), a pattern that is significantly non-random for LDMC and C:N. This study demonstrates that P. coronata might act as a strong biotic filter responsible for species loss and functional changes. Our findings suggest that in response to increasing competition with this invasive plant, resident and novel plant communities shift toward less diverse and more competitive assemblages. Nevertheless, the intensity of this filtering is habitat dependent (e.g. less filtering effect under mahogany trees). Lastly, changes in resource acquisition strategies (mainly nutrient-based) in particular in low nutrient status of rainforest soils, could lead to long-term impacts on tree regeneration, in turn causing large-scale changes in ecosystem properties. [ABSTRACT FROM AUTHOR]

Despite their key role in biodiversity conservation, forests in the Congo Basin are increasingly threatened by human activities, but it remains challenging to assess the impact of forest degradation under a more or less intact canopy. Likewise, forest recovery following agricultural abandonment remains poorly understood in the Congo Basin. Here, we surveyed 125 vegetation quadrats across 25 forest inventory plots in the Yangambi area. We aimed to find associations between both selective logging and forest recovery, and a range of forest community and tree community trait characteristics, as compared to reference undisturbed old-growth forest. We found that plots in undisturbed old-growth forest harboured both more tree individuals and tree species with a higher wood density as compared to plots in disturbed old-growth forest. In addition, their tree community composition was significantly different, whereas species diversity recovered since relatively recent agricultural abandonment (< 60 years), community composition and forest structure remained significantly different from the plots in undisturbed old-growth forest. Our study provides some insights into the rate of forest recovery in the Congo basin after agricultural abandonment and highlights the need of proper conservation of the remaining relatively undisturbed old-growth forests. Finally, we stress the need for more extensive vegetation surveys in the Congo Basin to further unravel the effects of anthropogenic disturbance. [ABSTRACT FROM AUTHOR]

Vessel diameter variation along the hydraulic pathway determines how much water can be moved against the force of gravity from roots to leaves. While it is well-documented that tree size scales with vessel diameter variation at the stem base due to the effect of basipetal vessel widening, much less is known whether this likewise applies to terminal sun-exposed twigs. To analyze the effect of tree height on twig xylem anatomy, we compiled data for 279 tropical rainforest tree species belonging to 56 families in the lowlands of Jambi Province, Indonesia. Terminal upper-canopy twigs of fully grown individuals were collected and used for wood anatomical analysis. We show that hydraulically weighted vessel diameter (D h) and potential hydraulic conductivity (K p) of upper canopy twigs increase with tree height across species although the relationship was weak. When averaged across given tree height classes irrespectively of species identity, however, a strong dependency of tree height on D h and K p was observed, but not on the lumen-to-sapwood area ratio (A l: A x) or vessel density (VD). According to the comparison between actual tree height and the maximum tree height reported for a given species in the stand, we show that the vascular xylem anatomy of their terminal twigs reflects their canopy position and thus ecological niche (understory versus overstory) at maturity. We conclude that the capacity to move large quantities of water during the diurnal peak in evaporative demand is a prerequisite for growing tall in a humid tropical environment. [ABSTRACT FROM AUTHOR]

We here report for the first time the complete immature life cycle of a Neotropical skipper butterfly, Ebusus ebusus ebusus (Cramer, 1780), with a report of a new natural hostplant based on a single individual reared at Finca Las Piedras (Madre de Dios, Peru). An egg obtained in nature passed through four larval instars and reached the adult stage, feeding on a palm species identified as Mauritia flexuosa L.f. (Arecaceae: Calamoideae). We provide images of each life stage including illustrations of head capsules and larval shelter structures, as well as information on the duration of the stages. [ABSTRACT FROM AUTHOR]

We describe a new Pseudophilautus species, P. conniffae sp. nov. from southern Sri Lanka. It was previously confused with Pseudophilautus rus (Manamendra-Arachchi & Pethiyagoda). The new species differs from the latter by the combination of the following characters: fourth toe webbing to penultimate subarticular tubercle on inner and outer sides (vs. fourth toe webbing in between penultimate and anetpenultimate subarticular tubercles on inner and outer sides), presence of conical median lingual process (vs. absent), and black patches on the posterior flank, anterior and posterior edges of the thigh (vs. black patches on the anterior surface of the thigh). Pseudophilautus conniffae sp. nov. may be sympatric with P. limbus (Manamendra-Arachchi & Pethiyagoda), which shares certain characters with the new species. The new species is, however, distinguished from P. limbus by the following characters: having supernumerary tubercles on manus (vs. lacking), absence of frontoparietal ridges (vs. presence), fourth toe webbing to penultimate subarticular tubercle on both sides (vs. fourth toe webbing between penultimate and anetpenultimate subarticular tubercle on both sides), third toe webbing to distal subarticular tubercle on both sides (vs. distal subarticular tubercle on outer side and below penultimate subarticular tubercle on inner side), and having the dorsum light brown with dark brown patches (vs. black and yellow variegated pattern on dorsum). The new species may be restricted to the southwestern wet zone of Sri Lanka. It is compared with all known Pseudophilautus species and also provided with a field key to identify it from those species that are sympatric with it or inhabit the southwestern wet zone.

Batu Hampar Recreational Forest (BHRF) is a lowland dipterocarp forest located in the northwestern region of Peninsular Malaysia and has not been surveyed for its herpetofauna until now. A preliminary survey of the herpetofaunal diversity of BHRF was conducted from September 2018 to February 2019 resulting in 103 individuals (37 species) of amphibians and reptiles found. This includes 14 species of frogs from six families and 10 genera; 14 species of lizards from four families and 11 genera; eight species of snakes from five families and eight genera; and one species of freshwater turtle. From these results, Batu Hampar Recreational Forest has a high herpetofaunal diversity with a Simpson's Index of Diversity of 0.869 and a Shannon-Wiener Diversity Index of 2.930. In the future, additional surveys over longer periods of time should be conducted at BHRF to produce a more complete checklist. [ABSTRACT FROM AUTHOR]

Elevation gradients correlate with changes in several environmental conditions and are known to be related to animal abundance. Animals in regions with a naturally limited extent of lowland rainforest are expected to have evolved adaptations to intermediate elevations that provided a stable environment during their evolution.Since the lowland rainforest of Madagascar has a limited extent and suffers from increasing anthropogenic pressure, it is essential to understand how well species tolerate intermediate and high elevations. In this study, we aim to quantify the relationship between lemur abundance and elevation in the eastern rainforest of Madagascar.We correlated abundance data on 26 lemur species (10 genera), including 492 records from 26 studies, with elevation. We analysed the consistency of correlations across species with a meta‐analytical approach. We controlled for species' body mass, elevational range and median elevation. We then ran generalised linear mixed models to determine whether lemur abundance was related to elevation, body mass, plant productivity and anthropogenic disturbance.Overall, the abundance of lemur species in Malagasy rainforests was negatively correlated with elevation, and species occupying broader elevational ranges showed stronger correlations. Body mass was not related to species' tolerance of high elevations. Even though several lemur species are able to occupy the entire elevation gradient, the few remaining patches of lowland rainforests host lemur species at greater abundances than other sites. Abundance across species was negatively related to body mass, elevation and seasonality in plant productivity and positively related to plant productivity.Despite the ecological flexibility of many lemur species, the remnant patches of lowland rainforests host the highest levels of lemur abundance and are key to lemur conservation. It is crucial to preserve this priority habitat both for biodiversity conservation and for our understanding of lemur adaptations. [ABSTRACT FROM AUTHOR]

A guild is a group of species that have similar requirements of resource and foraging behavior. The knowledge of insectivorous guild could explain foraging patterns, niche exploitation, and competition in a tropical forest. This information could help to monitor the forest by understanding the guild composition and their response to the habitat condition. In order to describe the guild composition and niche overlap of insectivorous birds, we observed all of the individual birds found foraging in the evergreen forest, Baluran National Park. Bray-Curtis similarity index and Pianka niche overlap index were used to analyze the data and grouping the birds into a guild. The cluster analysis consists of 27 bird species revealed 4 guilds: ground gleaner, foliage gleaner, aerial sallier, and bark prober. Based on species richness, foliage gleaner dominates the other groups while bark prober had the least species richness in the evergreen forest. The scarcities of feeding substrate affect guild existence and proved that the diversity of habitat substrate could affect the diversity of guild in an area. Ten congeneric species were found in this habitat and most of them are grouped into foliage gleaner. The junglefowl has the highest niche overlap than any other congeneric species. It seemed that the more specific the foraging substrate niche, the higher the competition among sympatric species. The level of congeneric/sympatric species competition could become the indicator to monitor a specific habitat or forest by understanding their niche partitioning, especially if the species is protected by the law. [ABSTRACT FROM AUTHOR]

The climate change impacts are felt by all facets and sectors of ecosystems, covering flora, fauna and environment. Sri Lanka is considered as a vulnerable, small island country that is under serious threat from climate change impacts. The most profound impacts of climate change in Sri Lanka will be on agriculture and food security, water and coastal resources, biodiversity changes, and human health. Sri Lanka's biodiversity is significantly important both on a regional and global scale as it has the highest species density for flowering plants, amphibians, reptiles, and mammals. Sri Lanka's varied ecosystems provide many services that are of significant economic value and play a crucial role in providing goods and ecosystem services. The subsequent sections featuring specific aspects of biodiversity in forests, freshwater wetlands, coastal and marine systems and agricultural systems, provide greater detail on the ecosystem services and bio-resources. Habitat loss and fragmentation, invasive alien species, deforestation and forest degradation, development projects, environmental pollutions and climate change (global warming) are the major threats to the biodiversity of the country. Climate change impacts on environment lead to a reduction in the distribution and abundance of species, especially endemics, which may even result in their global extinction. The introduction of various policies and guidelines in relation to environment is a good sign for conservation of ecosystems and biodiversity. The government of Sri Lanka has been implementing various environmental projects aiming at reducing deforestation and degradation of ecosystems. Policies and measures already developed under such initiatives will no doubt preserve natural habitats for plant and animal species. However, being a developing country with many economic challenges, the funds and expertise available for monitoring climate change impacts and biodiversity conservation are not sufficient.

The lowland rainforests of Meghalaya, India represent the westernmost limit of the rainforests north of the Tropic of Cancer. These forests, on the Shillong plateau, are akin to Whitmore's ‘tropical lowland evergreen rainforest’ formation and exhibit striking similarities and conspicuous differences with the equatorial rainforests in Asia-Pacific as well as tropical seasonal rainforests in southwestern China near the Tropic of Cancer. We found these common attributes of the rainforests in Meghalaya: familial composition with predominance of Euphorbiaceae, Lauraceae, Meliaceae, Moraceae, Myrsiticaceae, Myrtaceae and Rubiaceae; deciduousness in evergreen physiognomy; dominance of mega- and mesophanerophytic life-forms; abundance of species with low frequency of occurrence (rare and aggregated species); low proportional abundance of the abundant species; and truncated lognormal abundance distribution. The levels of stand density and stand basal area were comparable with seasonal rainforests in southwestern China, but were lower than equatorial rainforests. Tropical Asian species predominated flora, commanding 95% of the abundance. The differences include overall low stature (height) of the forest, inconspicuous stratification in canopy, fewer species and individuals of liana, thicker understory, higher proportion of rare species, absence of locally endemic species and relatively greater dominance of Fagaceae and Theaceae. The richness of species per hectare (S) was considerably lower at higher latitudes in Meghalaya than in equatorial rainforests, but was comparable with seasonal rainforests. Shannon's diversity index (H′ = 4.40 nats for ≥10 cm gbh and 4.25 nats for ≥30 cm gbh) was lower on higher latitudes in Meghalaya in comparison to species-rich equatorial rainforests, but it was the highest among all lowland rainforests near the Tropic of Cancer.

Focusing on nematodes and their well-developed indices of community, ecosystem structure and function, we investigated the effects of the conversion of rainforest into rubber and oil palm plantations in Sumatra, Indonesia. Land use did not affect the total abundance of litter- and soil-dwelling nematodes, neither in riparian nor in well-drained sites. However, the rainforest nematode community differed from communities in plantations, with differences in litter being more pronounced compared to soil. In litter, fungivores and nematodes with short generation time (c-p2) increased in monoculture plantations, while that of bacterivores, herbivores, and nematodes with longer generation time and higher sensitivity to disturbances (c-p3) decreased. This indicates higher environmental pressure on nematodes in monoculture plantations than in rainforest. In soil of monoculture plantations, bacterivores, and c-p3 nematodes decreased while herbivores increased. This suggests that the damage of plants by nematodes in oil palm plantations exceeds that in rainforest. Overall, nematode functional diversity indices suggest that the stability of the decomposer community is higher in rainforest compared to monoculture plantations. Importantly, functional diversity indices were much more meaningful than nematode abundance. Further, changes with land use manifested more in litter than in soil, reflecting that nematode communities in soil are buffered against changes in land use and associated environmental conditions. Therefore, to fully assess changes in the structure and functioning of decomposer systems with changes in land use, the litter layer, which often receives little attention, requires more careful consideration.

Though tropical forest ecosystems are among the largest natural sources of the potent greenhouse gas nitrous oxide (N2O), the spatial distribution of emissions across landscapes is often poorly resolved. Leaf cutter ants (LCA; Atta and Acromyrmex, Myrmicinae) are dominant herbivores throughout Central and SouthAmerica, and influencemultiple aspects of forest structure and function. In particular, their foraging creates spatial heterogeneity by concentrating large quantities of organic matter (including nitrogen,N) fromthe surrounding canopy into their colonies, and ultimately into colony refuse dumps. Here, we demonstrate that refuse piles created by LCA species Atta colombica in tropical rainforests of Costa Rica provide ideal conditions for extremely high rates of N2O production (high microbial biomass, potential denitrification enzyme activity, N content and anoxia) and may represent an unappreciated source of heterogeneity in tropical forest N2O emissions. Average instantaneous refuse pile N2O fluxes surpassed background emissions by more than three orders of magnitude (in some cases exceeding 80 000 mg N2O-N m22 h21) and generating fluxes comparable to or greater than those produced by engineered systems such as wastewater treatment tanks. Refuse-concentrating Atta species are ubiquitous in tropical forests, pastures and production ecosystems, and increase density strongly in response to disturbance. As such, LCA colonies may represent an unrecognized greenhouse gas point source throughout the Neotropics. [ABSTRACT FROM AUTHOR]

[Display omitted] • Complementary sampling methods detected species not attracted to dung-baited pitfalls. • Additional species increased the functional volume of the dung beetle assemblage. • Functional traits of additional species were rarer than expected by chance. • FITs and visual transects had the highest values of taxonomic and functional turnover. • Visual transects detect functionally rare trophic specialists. The functional space of an ecological community is not evenly filled by its species. Instead, it is usually divided into areas of high species density, where species with common combinations of functional traits are grouped into species rich clusters, while lower density areas are filled with species poor clusters or isolated species with uncommon or unique combinations of traits. Species whose functional traits differ from those of the rest of the community are expected to play distinct ecological roles and over-contribute to ecosystem functionality. Sampling methods used to characterize arthropod assemblages usually target subsets of the community and filter species based on their functional traits, reducing the probability of detecting species with uncommon combinations of functional traits. Consideration of these species is particularly important for characterizing the functional structure and resilience of ecological communities inhabiting threatened ecosystems such as lowland Amazonian rainforests, in which dung beetles play multiple ecological roles and are commonly used as ecological indicators. In this study, we characterize the functional structure of a diverse Amazonian dung beetle assemblage using five different sampling methods (dung- and carrion-baited pitfalls, dung-baited aerial traps, flight interception traps, and visual transects) and 18 different functional traits. Our main objective is to assess the suitability of these methods for the detection of the functional volume of the assemblage and of species with uncommon or unique combinations of functional traits that are expected to support vulnerable ecosystem functions. We found that, although dung-baited pitfalls (DPF) detected the highest species richness and proportion of the functional volume, they did not detect 30 species out of 103 and over 20% of the functional volume of the assemblage. The additional sampling methods captured more species with uncommon combinations of functional traits than expected by chance, some of which were trophic specialists not attracted to DPFs. The use of complementary sampling methods resulted in a better characterization of the functional structure of dung beetle communities inhabiting both terra firme and floodplain Amazonian rainforests and revealed functional resilience and rare species playing ecological roles overlooked by DPFs. The consideration of these species is of great importance given the threats that tropical rainforests face worldwide. [ABSTRACT FROM AUTHOR]

Along environmental gradients, communities are expected to be filtered from the regional species pool by physical constraints, resource availability, and biotic interactions. This should be reflected in species trait composition. Using data on species-rich moth assemblages sampled by light traps in a lowland rainforest landscape in Costa Rica, we show that moths in two unrelated clades (Erebidae-Arctiinae; Geometridae) are much smaller-sized in oil palm plantations than in nearby old-growth forest, with intermediate values at disturbed forest sites. In old-growth forest, Arctiinae predominantly show aposematic coloration as a means of anti-predator defense, whereas this trait is much reduced in the prevalence in plantations. Similarly, participation in Müllerian mimicry rings with Hymenoptera and Lycidae beetles, respectively, is rare in plantations. Across three topographic types of old-growth forests, community-weighted means of moth traits showed little variation, but in creek forest, both types of mimicry were surprisingly rare. Our results emphasize that despite their mobility, moth assemblages are strongly shaped by local environmental conditions through the interplay of bottom–up and top–down processes. Assemblages in oil palm plantations are highly degraded not only in their biodiversity, but also in terms of trait expression.

Nigeria is the most populous country in Africa and has highly diverse forest ecosystems. Unfortunately, this rich vegetation continues to decline at an alarming rate; 21% of its forest cover has been lost between 1990 and 2005. The lowland rainforest area which is the main source of hardwood timber resources has been depleted to less than 3.94 million ha and continues to decline. The major causes of deforestation and forest degradation are crude oil exploration and exploitation in the coastal regions, increased intensity of land fallow systems, fuelwood collection, charcoal production, illegal logging, infrastructural development and urbanisation. The drastic reduction and degradation of forest cover in the last 50 years have diminished the productive and protective functions of the forests. This article highlights the historical development of forestry and forestry education in Nigeria. It discusses the issues related to policy and legislation development, the challenges facing the forest industries as well as the economic contributions from the forestry sector. It proposes the need for regulated forest exploitation, enactment and implementation of national afforestation and reforestation programmes, and the need for the revitalisation of the sector through a sustainable forest management approach. [ABSTRACT FROM AUTHOR]

Conspecific effects of neighbours on small-tree survival may have a role in tree population dynamics and community composition of tropical forests. This notion was tested with data from two 4-ha plots in lowland forest at Danum, Sabah (Borneo), for a 21-year interval (censuses at 1986, 1996, 2001, 2007). Species with ≥45 focal trees 10 to <100 cm stem girth per plot in 1986 were selected. Logistic regressions fitted mean focal tree size and mean inverse-distance-weighted basal area abundance of neighbours (within 20 m), for the periods over which each focus tree was alive. Coefficients of variation of neighbourhood basal area abundance, both spatially and temporally, quantified the changing environment of each focus tree. Fits were critically and individually evaluated, with corrections for spatial autocorrelation. Conspecific effects at Danum was generally very weak or non-existent: species' mortality rates varied also across plots. The main reasons appear to be that (1) species were not dense enough to interact despite frequent although weak spatial aggregation, and their neighbourhoods were highly differing in species composition; and (2) these neighbourhoods were highly variable temporally, meaning that focus trees experienced stochastically fluctuating neighbourhood environments. Only one species, Dimorphocalyx muricatus, showed strong conspecific effects (varying between plots) which can be explained by its distinct ecology. This understorey species is highly aggregated on ridges and is drought-tolerant. That this functionally and habitat-specialized species, has implied intraspecific density-dependent feedback in its dynamics is a remarkable indication of the overall processes maintaining stability of the Danum forest. [ABSTRACT FROM AUTHOR]

A total of six Amblyomma tapirellum ticks were found for the first time in rainforest from the lowland to the southern Pacific of Costa Rica. Tick identification was carried out by morphology and afterward confirmed by molecular analysis, using polymerase chain reaction (PCR) and DNA barcoding. Further studies are required to determine the distribution of A. tapirellum and this species' potential as a vector of bacterial agents to humans and wild hosts. [ABSTRACT FROM AUTHOR]

Background: The Buff-spotted Woodpecker (Campethera nivosa) is a resident bird species that is distributed in lowland rainforest habitats from western to eastern Africa. We developed species-speciic microsatellite markers to examine the population genetics of this species. Findings: Twenty-one microsatellite loci were isolated from C. nivosa. Of these, 15 were found to amplify consistently. These loci were then tested for variability in 15 individuals from diferent lowland forest localities. The number of alleles ranged from 3 to 13 per locus, with observed and expected heterozygosity ranging from 0.100 to 0.917 and 0.485 to 0.901, respectively. Four loci exhibited signiicant heterozygote deiciency while one had an excess of heterozygotes. None of the loci exhibited linkage disequilibrium. Conclusion: These polymorphic microsatellite markers will be used to study genetic variability in populations of C. nivosa across either sides of the Congo River to evaluate the efect of the river as a barrier to gene low. [ABSTRACT FROM AUTHOR]

The article reports on a survey of bat population diversity at Bukit Barisan Selatan National Park in Sumatra, Indonesia. Topics discussed include the species discovered during the survey, the distinct morphs of Chironax melanocephaus found in the area and the significance of the national park in the maintenance of bat diversity in the island.

The productivity of tropical forests is driven by climate (precipitation, temperature, and light) and soil fertility (geology and topography). While large-scale drivers of tropical productivity are well established, knowledge on the sensitivity of tropical lowland net primary production to climate anomalies remains scarce. We here analyze seven consecutive years of monthly recorded tropical forest aboveground net primary production (ANPP) in response to a recent El Niño-Southern Oscillation (ENSO) anomaly. The ENSO transition period resulted in increased temperatures and decreased precipitation during the El Niño dry period, causing a decrease in ANPP. However, the subsequent La Niña wet period caused strong increases in ANPP such that drought-induced reductions were overcompensated. Most strikingly, the climatic controls differed between canopy production (CP) and wood production (WP). Whereas CP showed strong seasonal variation but was not affected by ENSO, WP decreased significantly in response to a 3°C increase in annual maximum temperatures during the El Niño period but subsequently recovered to above predrought levels during the La Niña period. Moreover, the climate sensitivity of tropical forest ANPP components was affected by local topography (water availability) and disturbance history (species composition). Our results suggest that projected increases in temperature and dry season length could impact tropical carbon sequestration by shifting ANPP partitioning toward decreased WP, thus decreasing the carbon storage of highly productive lowland forests. We conclude that the impact of climate anomalies on tropical forest productivity is strongly related to local site characteristics and will therefore likely prevent uniform responses of tropical lowland forests to projected global changes. [ABSTRACT FROM AUTHOR]

Selective logging is a major driver of rainforest degradation across the tropics. Two competing logging strategies are proposed to meet timber demands with the least impact on biodiversity: land sharing, which combines timber extraction with biodiversity protection across the concession; and land sparing, in which higher intensity logging is combined with the protection of intact primary forest reserves. We evaluate these strategies by comparing the abundances and species richness of birds, dung beetles and ants in Borneo, using a protocol that allows us to control for both timber yield and net profit across strategies. Within each taxonomic group, more species had higher abundances with land-sparing than land-sharing logging, and this translated into significantly higher species richness within land-sparing concessions. Our results are similar when focusing only on species found in primary forest and restricted in range to Sundaland, and they are independent of the scale of sampling. For each taxonomic group, land-sparing logging was the most promising strategy for maximizing the biological value of logging operations. [ABSTRACT FROM AUTHOR]

The accurate estimation of above ground biomass in the natural forests of Papua New Guinea is a key component for the successful implementation of the REDD policy in the country. Biomass densities in a lowland rainforest site located at the northeast of the country were differentiated with Landsat digital images throughout normalized difference vegetation index (NDVI). Submaps of 4,377.69 ha of bands 3 and 4 were georeferenced with affine transformation and a RMSE of 0.529. The calculated NDVI map was sliced to separate its pixel values into 5 classes as they are distributed in the histogram with the assistance of ground truth points. The method is simple, fast and reliable, however swampy palm forest could not be discriminated from dense forests; and different bare land types had to be grouped into a single major class. Therefore other vegetation indexes and/or band ratios are recommended to be tested using images of higher spatial resolution to accurately differentiate more classes.

In an intensive mark-release-recapture study of all butterfly species in a tropical rainforest understory, 5903 individuals from 90 butterfly species (from the estimated total of 104 ± 9 species present in understory habitat) were marked, and 1308 recaptured at least once., The study proved that mark-recapture methods are feasible in tropical rainforests, but also showed its limitations, as after 232 person-days of sampling we could only characterise dispersal for one-third of the species present., The mean dispersal distance was 184 ± 46.1 m per species, while for six of the 14 species studied >1% of individuals were estimated to disperse 1 km or more. These parameters are, however, strongly dependent on the size and spatial configuration of the study plots, particularly in large homogeneous habitats. A new method proposed here to correct this bias revised the mean distance between two captures from 135 ± 33.6 to 325 ± 87.0 m per species., These results, in combination with data from large permanent rainforest plots, suggest that most woody plant species in tropical forests are sufficiently abundant to serve as host plant species even to monophagous Lepidoptera species. [ABSTRACT FROM AUTHOR]

Asian rainforests suffer from massive deforestation but remain less studied pantropically. Although Sri Lanka is a severely threatened biodiversity hot spot with high endemicity and unique conservation challenges, few have investigated how fauna respond to environmental perturbations caused by human modification of habitats. We investigated differences in the diversity and community composition of amphibians and butterflies in primary and selectively logged forests ( SLF), home gardens and plantations in the Sinharaja lowland tropical forest and surrounding areas. A Bayesian multi-model inference approach was then used to identify environmental variables that explained differences in richness and abundance patterns among sites. Amphibian species richness ( SPR) was highest in a forest habitat, and community composition differed between forest and disturbed habitats. In contrast, butterfly SPR increased with increasing disturbance. Butterfly diversity patterns were best explained by climatic variables, while structural habitat parameters were the best predictors of amphibian patterns. Based on research findings, the protection of primary forest habitats is essential for amphibian conservation. Regenerating SLF can be of high conservation value especially if substantial pristine habitat remains conserved in the landscape. Anthropogenic habitats at the periphery of forests require realistic management recommendations to support the species inhabiting, visiting or migrating through them. Different environmental predictors for butterflies and amphibians underscore the importance of including multiple indicator taxa in surveys that are intended to inform habitat management. [ABSTRACT FROM AUTHOR]

From June, 2007, to February, 2009, the Waria Valley Community Conservation and Sustainable Livelihoods Project (WVCP) completed an inventory survey of the birds of the lower Waria Valley, Morobe Province, Papua New Guinea. Four land use types -- agricultural, secondary forest edge, primary forest edge and primary forest -- were surveyed using Mackinnon list surveys. In total, 125 species representing 43 families were identified, of which 54 (43.2%) are endemic to the islands of New Guinea and the Bismark Archipelago. The avifauna of primary forest edge and primary forest was more species rich and diverse than that of agricultural habitats. Agricultural habitats also differed significantly in both overall community composition and some aspects of guild composition compared to all three forested habitats. Nectarivores and insectivore-frugivores formed a significantly larger proportion of species in agricultural habitats, whereas obligate frugivores formed a significantly greater proportion in forested habitats. We propose further survey and management initiatives that could help contribute to the conservation and sustainable use of the area's important biological resources. [ABSTRACT FROM AUTHOR]

Termites play a prominent role in the decomposer food web as ‘ecosystem engineers’. However, the effect of spatial scales on termite assemblages has, to date, been poorly studied. Here, we evaluate the contribution of two spatial levels [transects (100 m × 2 m) and sections within transects (5 m × 2 m)] on the local termite assemblage of a continuous mixed secondary lowland rainforest in southeast Cameroon. Standardized 100 m × 2 m transects were run in five vegetation types to cover more of the heterogeneity of this forest. The additive partitioning of the species richness of all species, soil- and wood-feeder species was statistically tested with sample-based randomization... [ABSTRACT FROM AUTHOR]

Abstract: La Réunion Island (Indian Ocean) is one of the tropical oceanic islands that exhibits a lowland forest still not destroyed by human activities and by introduced species. In order to protect and conserve native intact habitats, information concerning their functioning is needed. We measure the biomass and litterfall of the Marelongue Reserve lowland rainforest on a permanent plot and examine what is the part played by the different species as well as the role of seasonality and cyclones. The total biomass estimated at 535t/ha is relatively consistent with biomasses measured in other tropical forests. Over 92% of the biomass is due to 10 species only. The annual fine litterfall, measured at 7.6t/ha during the two studied years, is similar to annual litterfall measured in similar ecosystems and is strongly affected by cyclones. The litterfall seasonality seemed to be linked to temperature fluctuations, rather than to either of the other two studied climatic factors (rainfall and wind speed). The results of this study will define valuable basic information for conservation and management of fragmented rainforest remnants. [Copyright &y& Elsevier]

A corticolous species, Anisomeridium flavovulcanus, is described. It has so far been found in the Carribean and Pacific lowland rainforests of Costa Rica, where it is a frequent lichen in the understorey. This conspicuous lichen is characterized by large conical conidiomata, which release a yellow conidial mass at the apex. Dimorphic conidia occur in the same conidiomata: 1-septate microconidia and thick walled globose macroconidia. Ascomata were found only twice; the inconspicuous perithecia are hemispherical, semi-emergent with an apical ostiole, the asci are cylindrical with a cruciform ocular chamber and the ascospores are uniseriately arranged. [ABSTRACT FROM AUTHOR]

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1. The parasitic wasp family lchneumonidae (Hymenoptera) is of great interest because it has been claimed that its species richness does not increase with decreasing latitude. 2. No extensive studies of the family have been conducted in South American localities. 3. Arthropods were sampled using 27 Malaise traps in the Allpahuayo-Mishana National Reserve (56 000 ha) in the north-eastern Peruvian Amazonian lowland rainforest. The total duration of the sampling programme was 185 Malaise trap months. 4. Altogether, 88 species were collected. This is one of the highest local pimpline and rhyssine species numbers ever recorded. A comparison with results from Mesoamerica revealed that at equal numbers of individuals sampled, the number of Pimplinae and Rhyssinae species in Peruvian Amazonia is at least twofold compared with lowland locations in Mesoamerica and somewhat higher than in the most species-rich Costa Rican higher altitude localities. 5. Non-parametric methods of estimating species richness were applied. These suggest that additional sampling would yield a considerable number of new Pimplinae and/or Rhyssinae species. [ABSTRACT FROM AUTHOR]

Dacine fruit flies in the Kau Wildlife Area, a patch of lowland rainforest near Madang, Papua New Guinea, were studied during the dry season of 1996 using Steiner traps baited with cuelure and methyl eugenol. A limited amount of data on larval hosts was obtained from fruit samples collected in the reserve and held in the laboratory. Fruit flies were also trapped at some other lowland rainforest sites near Madang to determine if there were any major differences in species composition between sites. Over 50 species of fruit flies were collected in the Kau Wildlife Area, 25% of which appeared to be undescribed. Trapping at the other lowland rainforest sites yielded only one additional species. [ABSTRACT FROM AUTHOR]

Lake-sediment cores from Laguna Bonilla and Laguna Bonillita provide some of the first evidence of prehistoric human impacts on lowland rainforests in Costa Rica. The longer Bonillita sediment record docu ments permanent settlement of the lake shores by 2560 BP, about 600 years earlier than previously inferred from the archaeological record. Zea pollen and charcoal fragments in cores from both lakes indicate a subsist ence strategy that included maize cultivation and some use of fire. A dramatic decline in Myrsine pollen percentages about 1300 BP suggests local eradication of this woody plant, likely as a result of land clearance and/or the use of Myrsine for construction. [ABSTRACT FROM PUBLISHER]