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Anthropogenic disturbance of tropical humid forests leads to habitat loss, biodiversity decline, landscape fragmentation, altered nutrient cycling and carbon sequestration, soil erosion, pest/pathogen outbreaks, among others. Nevertheless, the impact of these alterations in multitrophic interactions, including host–pathogen and vector–pathogen dynamics, is still not well understood in wild plants. This study aimed to provide insights into the main drivers for the incidence of herbivory and plant pathogen damage, specifically, into how vegetation traits at the local and landscape scale modulate such interactions. For this purpose, in the tropical forest of Calakmul (Campeche, Mexico), we characterised the foliar damage caused by herbivores and pathogens in woody vegetation of 13 sampling sites representing a gradient of forest disturbance and fragmentation in an anthropogenic landscape from well preserved to highly disturbed and fragmented areas. We also evaluated how the incidence of such damage was modulated by the vegetation and landscape attributes. We found that the incidence of damage caused by larger, mobile, generalist herbivores, was more sensitive to changes in landscape configuration, while the incidence of damage caused by small and specialised herbivores with low dispersal capacity was more influenced by vegetation and landscape composition. In relation to pathogen symptoms, the herbivore-induced foliar damage seems to be the main factor related to their incidence, indicating the enormous importance of herbivorous insects in the modulation of disease dynamics across tropical vegetation, as they could be acting as vectors and/or facilitating the entry of pathogens by breaking the foliar tissue and the plant defensive barriers. The incidence of pathogen damage also responded to vegetation structure and landscape configuration; the incidence of anthracnose, black spot, and chlorosis, for example, were favoured in sites surrounded by smaller patches and a higher edge density, as well as those with a greater aggregation of semi-evergreen forest patches. Fungal pathogens were shown to be an important cause of foliar damage for many woody species. Our results indicate that an increasing transformation and fragmentation of the tropical forest of southern Mexico could reduce the degree of specialisation in plant–herbivore interactions and enhance the proliferation of generalist herbivores (chewers and scrapers) and of mobile leaf suckers, and consequently, the proliferation of some symptoms associated with fungal pathogens such as fungus black spots and anthracnose. The symptoms associated with viral and bacterial diseases and to nutrient deficiency, such as chlorosis, could also increase in the vegetation in fragmented landscapes with important consequences in the health and productivity of wild and cultivated plant species. This is a pioneering study evaluating the effect of disturbances on multitrophic interactions, offering key insights on the main drivers of the changes in herbivory interactions and incidence of plant pathogens in tropical forests. [ABSTRACT FROM AUTHOR]

Anthropogenic disturbance of tropical humid forests leads to habitat loss, biodiversity decline, landscape fragmentation, altered nutrient cycling and carbon sequestration, soil erosion, pest/pathogen outbreaks, among others. Nevertheless, the impact of these alterations in multitrophic interactions, including host–pathogen and vector–pathogen dynamics, is still not well understood in wild plants. This study aimed to provide insights into the main drivers for the incidence of herbivory and plant pathogen damage, specifically, into how vegetation traits at the local and landscape scale modulate such interactions. For this purpose, in the tropical forest of Calakmul (Campeche, Mexico), we characterised the foliar damage caused by herbivores and pathogens in woody vegetation of 13 sampling sites representing a gradient of forest disturbance and fragmentation in an anthropogenic landscape from well preserved to highly disturbed and fragmented areas. We also evaluated how the incidence of such damage was modulated by the vegetation and landscape attributes. We found that the incidence of damage caused by larger, mobile, generalist herbivores, was more sensitive to changes in landscape configuration, while the incidence of damage caused by small and specialised herbivores with low dispersal capacity was more influenced by vegetation and landscape composition. In relation to pathogen symptoms, the herbivore-induced foliar damage seems to be the main factor related to their incidence, indicating the enormous importance of herbivorous insects in the modulation of disease dynamics across tropical vegetation, as they could be acting as vectors and/or facilitating the entry of pathogens by breaking the foliar tissue and the plant defensive barriers. The incidence of pathogen damage also responded to vegetation structure and landscape configuration; the incidence of anthracnose, black spot, and chlorosis, for example, were favoured in sites surrounded by smaller patches and a higher edge density, as well as those with a greater aggregation of semi-evergreen forest patches. Fungal pathogens were shown to be an important cause of foliar damage for many woody species. Our results indicate that an increasing transformation and fragmentation of the tropical forest of southern Mexico could reduce the degree of specialisation in plant–herbivore interactions and enhance the proliferation of generalist herbivores (chewers and scrapers) and of mobile leaf suckers, and consequently, the proliferation of some symptoms associated with fungal pathogens such as fungus black spots and anthracnose. The symptoms associated with viral and bacterial diseases and to nutrient deficiency, such as chlorosis, could also increase in the vegetation in fragmented landscapes with important consequences in the health and productivity of wild and cultivated plant species. This is a pioneering study evaluating the effect of disturbances on multitrophic interactions, offering key insights on the main drivers of the changes in herbivory interactions and incidence of plant pathogens in tropical forests.

The new species Ormosia corcovada (Fabaceae, Papilionoideae, Ormosieae) from the lower Cauca River basin in NW Colombia is described and illustrated, and its taxonomic affinities are discussed. Specimens of Ormosia corcovada are usually confused with Ormosia holerythra. Both species belong to Ormosia section Unicolores but are geographically and morphologically distinct, especially with respect to leaflet shape and number of secondary veins. Se describe Ormosia corcovada (Fabaceae, Papilionoideae, Ormosieae), una nueva especie de la región del Bajo Cauca, NO de Colombia. La nueva especie se ilustra y se discuten sus relaciones taxonómicas. Los especímenes de Ormosia corcovada son usualmente determinados como Ormosia holerythra Ducke. Ambas especies pertenecen a Ormosia sección Unicolores, pero su distribución geográfica y morfología, principalmente de folíolos y número de nervaduras secundarias, son diferentes. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal fungi (AMF) play an important role in the dynamic of plant community in the south American Atlantic Rainforest biome. Even in protected areas, this biome is under several anthropic impacts, which can cause shifts in the soil microbiota, including AMF. This study aimed to determine the structure and composition of AMF community in areas of native Atlantic Forest and in natural regeneration and to identify which abiotic factors are influencing this community in these areas. Soil samples were collected at Monte Pascoal National and Historical Park, in Southern Bahia, in native and natural regeneration areas of Atlantic Forest in two seasons (rainy and dry). Greater number of glomerospores and richness and diversity of AMF were found in the area under regeneration, with differences between seasons being observed only for the number of glomerospores. Seventy-seven species of AMF were recorded, considering all areas and seasons, with Acaulospora and Glomus being the most representative genera. Greater abundance of species of the genera Acaulospora, Claroideoglomus, and Septoglomus was found in the regeneration area. The AMF community differed between the study areas, but not between seasons, with soil attributes (pH, K, Al, Mg, m, and clay) structuring factors for this difference in the AMF community. Atlantic Forest areas in natural regeneration and the soil edaphic factors provide changes in the structure and composition of the AMF community, increasing the richness and diversity of these fungi in conservation units. [ABSTRACT FROM AUTHOR]

Based on a set of reference indicators, a tool was designed for the evaluation “ex post” of sustainability of units of managed natural forests in Costa Rica. This set was developed using a hierarchical structure of principles, criteria and indicators of sustainability. The resulting reference list consists of 5 principles, 12 criteria and 30 indicators, classified as essential by a group of experts in forest management in Costa Rica. The set of indicators allows studying the dimensions and attributes that delimit the sustainability of the ecosystems. The selection procedure and the likely contribution of this set to forest management addresses, firstly, the economic, social, ecosystemic and institutional conditions of Costa Rica. However, the set of indicators is useful for other regions of the world, previous adaptation of the threshold values to the local conditions of the ecosystem. Additionally, the ecosystemic dimension (productivity, stability, adaptability) is ratified as a condition of first order for the sustainability, but the experts reinforce the idea that the institutional dimension (equity and governance) is a challenge for the evaluation of sustainability.

The Tropical Forestry Center (CFT) "Pedro Antonio Pineda" (Buenaventura, Colombia), is the main academic training center with rural character at the Faculty of Forestry Engineering, University of Tolima, located at the territory of the community council of Afro-descendant communities. Between 2013 and 2017, observations were made in seven locations associated with three habitat types (open areas, forest edge and forest interior), mainly in April and September, to provide knowledge of the tropical forest birds of the CFT. In overall, 166 species were registered (20 orders and 40 taxonomic families); the order with the highest relative abundance was Passeriformes (62.6%) and the families with the highest relative abundance were Thraupidae (17.3%) and Tyrannidae (8.9%). There were 22 species nearly endemic and 31 with migratory status; from a regional context, most of the birds were recorded in open areas (44 species) followed by forest edge species (42 species). [ABSTRACT FROM AUTHOR]

A new species of the genus Caecilia (Caeciliidae) from the western foothills of the Serranía de los Yariguíes in Colombia is described. Caecilia pulchraserrana sp. nov. is similar to C. degenerata and C. corpulenta but differs from these species in having fewer primary annular grooves and a shorter body length. With this new species, the currently recognized species in the genus are increased to 35. Mitochondrial DNA sequences, including newly sequenced terminals representing two additional, previously unanalyzed species, corroborate the phylogenetic position of the new species within Caecilia and the monophyly of the genus. This analysis also included newly sequenced terminals of Epicrionops aff. parkeri (Rhinatrematidae) and trans- Andean Microcaecilia nicefori (Siphonopidae). Evidence was found for the non-monophyly of the family Siphonopidae and the siphonopid genera Microcaecilia and Siphonops. The implications of these results for caecilian systematics are discussed and the status of the trans- Andean populations of Caecilia degenerata is commented upon. [ABSTRACT FROM AUTHOR]

Tropical cyclones (TCs) are large‐scale disturbances that regularly impact tropical forests. Although long‐term impacts of TCs on forest structure have been proposed, a global test of the relationship between forest structure and TC frequency and intensity is lacking. We test on a pantropical scale whether TCs shape the structure of tropical and subtropical forests in the long term.We compiled forest structural features (stem density, basal area, mean canopy height and maximum tree size) for plants ≥10 cm in diameter at breast height from published forest inventory data (438 plots ≥0.1 ha, pooled into 250 1 × 1‐degree grid cells) located in dry and humid forests. We computed maps of cyclone frequency and energy released by cyclones per unit area (power dissipation index, PDI) using a high‐resolution historical database of TCs trajectories and intensities. We then tested the relationship between PDI and forest structural features using multivariate linear models, controlling for climate (mean annual temperature and water availability) and human disturbance (human foot print).Forests subject to frequent cyclones (at least one TCs per decade) and high PDI exhibited higher stem density and basal area, and lower canopy heights. However, the relationships between PDI and basal area or canopy height were partially masked by lower water availability and higher human foot print in tropical dry forests.Synthesis. Our results provide the first evidence that tropical cyclones have a long‐term impact on the structure of tropical and subtropical forests in a globally consistent way. The strong relationship between power dissipation index and stem density suggests that frequent and intense tropical cyclones reduce canopy cover through defoliation and tree mortality, encouraging higher regeneration and turnover of biomass. The projected increase in intensity and poleward extension of tropical cyclones due to anthropogenic climate change may therefore have important and lasting impacts on the structure and dynamics of forests in the future. We show that tropical cyclones have a long‐term impact on the structure of tropical and subtropical forests in a globally consistent way. Forests subject to frequent and intense cyclones exhibit higher stem density and lower canopy heights. The projected changes in tropical cyclone regime may therefore have important and lasting impacts on the structure of forests in the future. [ABSTRACT FROM AUTHOR]

Herbivore foraging is influenced by spatial and seasonal changes in the production of leaves and fruits. To understand how herbivores respond to these changes, it is necessary to identify their habitat preferences and how they use the vegetation available. In the Neotropical region, one of the largest terrestrial herbivores is the lowland tapir (Tapirus terrestris), a species important for its dual role as browser and seed disperser. The objective of this study was to determine the species and plant components (leaves, fruits) utilized by T. terrestris in different time periods and habitats, in relation to changes in food availability in the north-western Amazon. Tapir diet was established through identification of browsing signs and faecal analysis, from data collected in the field during the months of March, April, August and September of 2015. Plant species availability for browsing was sampled in ten 2 × 50-m transects and fruit productivity was estimated in linear transects (~9 km). We found that T. terrestris mostly consumed vegetative parts, i.e. fibre (70–90%), and to a lesser extent fruits (10–30%). Food consumption was selective and concentrated in habitats with higher availability of preferred plants. When fruit intake increased, selectivity in browsing became more intense and limited to preferred species. This information, coupled with our findings about seasonal differences in browsing vs. frugivory patterns, provides valuable knowledge for understanding how environmental heterogeneity may influence the foraging ecology of the lowland tapir. [ABSTRACT FROM PUBLISHER]

Copyright of Boletin SAO is the property of Sociedad Antioquena de Ornitologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Successional dynamics and environmental associations of 18 pioneer and 24 commercial tree species were studied in a 4-year chronosequence of logging gaps in a Bolivian tropical forest. Logging gap area ranged from 108 to 1246m2. Pioneer regeneration was 71–387 more abundant than that of commercial species in all harvest years. Pioneer saplings (>1.5m tall and <10cmdbh) were more abundant in 2- and 4-year-old gaps than in 1-year-old gaps, but pioneer seedlings (≤1.5m tall) were more abundant in 1-year-old openings. By contrast, there were no significant differences among harvest years in size class distributions of commercial seedlings or saplings. Some pioneers (Acacia polyphylla, Urera baccifera, Heliocarpus americana, Cecropia concolor, and Inga edulis) were associated with large gaps or coarse soils with high herbaceous cover. Among commercial trees, Ampelocera ruizii, Hura crepitans, and Pseudolmedia laevis were associated with fine textured soils, while Pouteria nemorosa was associated with high fern cover and rock outcrops. Although most logging gaps were dominated by a few pioneer species, the commercial species A. ruizii, H. crepitans, P. nemorosa, and Terminalia oblonga may eventually dominate many gaps. Notably absent among gap regeneration were some of the most commercially valuable tree species, such as Swietenia macrophylla, Cedrela fissilis, Cariniana ianeirensis, and Ficus boliviana. Outplanting programs may be needed to ensure successful regeneration of these rare but valuable species. [Copyright &y& Elsevier]

Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Liana infestations can be a problem in forests managed for timber because lianas decrease rates of tree growth, damage tree boles, and inhibit tree regeneration. To determine the area from which lianas colonize tree crowns in a liana-rich moist lowland forest in a timber concession in the Department of Santa Cruz, Bolivia, we described “liana sheds” of individual canopy trees (the area under the crown and beyond its margins from which lianas colonize trees). In the same area we tested the hypothesis that pre-logging cutting of lianas in a harvested tree’s liana shed reduces post-logging liana infestations. Prior to logging, 73% of 570 trees >10 cm in DBH representing 12 commercial species, carried at least one liana >2 cm DBH. Liana-infested trees hosted an average of 9.3 lianas (±0.45 S.E., range: 1–68). The mean area of the crown covered by lianas was 35% (±29.7 S.E.) but some trees (10%) were completely covered by lianas. “Liana shed areas” were a function of crown area and varied among tree species. Most lianas on trees were rooted below the crown of their host (90%); the number of lianas decreased with increasing distance from the crown edge, but lianas colonized trees from as far as 8 m beyond the crown. Overall, there was a significant reduction in the number of lianas in 22 felling gaps 8 months after logging where lianas were cut before logging compared with 22 control gaps. In control gaps, the majority of climbing lianas sprouted from the prostrate stems of fallen canopy lianas (81%), including 3.1 km/ha of stems that were rooted along the ground before logging. Liana regeneration in gaps after pre-logging liana cutting occurred mainly by stump sprouting (41%) and sprouting from prostrate stems (48%). Pre-felling liana cutting reduced liana cover in felling gaps by 9% only but reduced liana basal area by 69%. The results of this study suggest that tree crown area, shape, and height are among the most important factors determining the likelihood of liana colonization of canopy trees and that pre-logging liana cutting reduces post-logging liana proliferation in logging gaps. [Copyright &y& Elsevier]

The area disturbed and damage to the residual stand caused by planned diameter-limit logging was assessed in a tropical humid forest of Bolivia and compared with disturbance and damage reported in other studies in the neotropics with similar harvesting intensities. The forest was logged by a private company under a government concession. The harvest incorporated many reduced impact logging practices including pre-harvest tree inventories, planned placement of roads and skid trails, vine cutting, and directional felling. A total density of 4.35 trees/ha and 12.1 m3/ha of wood were harvested. It was estimated that logging disturbed 45.8% of the stand including 25% ground area disturbance in the form of skid trails, logging roads, and log landings and an additional 25% in canopy openings due to tree felling. On average, 44 trees were damaged for every tree extracted including 22 trees killed or severely damaged, 6 of them commercial species. The most common types of damage included uprooted stems, stem wounds to the cambial layer, and bark scrapes. Road width was found to be a significant factor determining the number of trees damaged along logging roads but not along skid trails. Damage to trees sustained along skid trails was found to be significantly less than the damage incurred along logging roads. Residual damage in felling gaps was positively related to the diameter-at-breast-height of the harvested trees. Comparisons with other planned operations revealed a higher percent ground area disturbed and a greater felling gap area per tree extracted. Higher ground area disturbance was mostly due to the greater area in skid trails, many of which appeared to be unnecessary. Larger felling gap sizes appeared to be at least partially attributed to the larger size of trees harvested relative to those in other forests. The results of this study suggest that reduced impact logging practices may also need to be accompanied by close supervision of field personnel, monetary incentives and/or disincentives to loggers, and post-logging site inspections to be implemented properly. [Copyright &y& Elsevier]

• The ecosystemic dimension is ratified as condition of first order for sustainability. • The experts reinforce that evaluate the institutional dimension is a challenge. • Using Delphi method represented great advantage in generate the PCI. Based on a set of reference indicators, a tool was designed for the evaluation " ex post " of sustainability of units of managed natural forests in Costa Rica. This set was developed using a hierarchical structure of principles, criteria and indicators of sustainability. The resulting reference list consists of 5 principles, 12 criteria and 30 indicators, classified as essential by a group of experts in forest management in Costa Rica. The set of indicators allows studying the dimensions and attributes that delimit the sustainability of the ecosystems. The selection procedure and the likely contribution of this set to forest management addresses, firstly, the economic, social, ecosystemic and institutional conditions of Costa Rica. However, the set of indicators is useful for other regions of the world, previous adaptation of the threshold values to the local conditions of the ecosystem. Additionally, the ecosystemic dimension (productivity, stability, adaptability) is ratified as a condition of first order for the sustainability, but the experts reinforce the idea that the institutional dimension (equity and governance) is a challenge for the evaluation of sustainability. [ABSTRACT FROM AUTHOR]