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1. Ants are the dominant insects in tropical forest canopies. The α and β diversities of ants change in response to forest disturbance. Understanding the response of ants to forest disturbance will help to guide ant conservation and forest management plans, especially in endangered ecosystems such as the tropical dry forest. 2. We analysed ant α and β diversities in 15 fragments (5 mature, 5 disturbed, and 5 secondary) of a tropical dry forest in central Mexico. We identified and measured all of the trees in two transects (10 × 50 m) established within each fragment. Pit‐fall traps were used to sample ants in all of the trees. 3. We identified 52 ant species (from a total of 11,524 individuals). The mature forest presented the greatest quantity of exclusive species and the highest α diversity. Ant composition differed among the mature forest but not between disturbed and secondary forest, and was related to tree size and richness. The β diversity was lower in the disturbed forest, reflecting the cost of biotic homogenization (15%). Among the β diversity components in all three forest types, this diversity was mainly influenced by turnover, while nestedness diminished in the disturbed forest. 4. In the tropical dry forest studied, anthropogenic disturbance homogenises the ant community, probably because the availability of resources is also homogenised, decreasing the α diversities of the canopy ants. Our results show the importance of the conservation of mature forests in terms of maintaining the diversity of canopy ants.

RESUMEN El estudio de la dieta de los murciélagos es importante para entender cómo se conforma su ensamblaje y cómo aportan a la dinámica de los bosques. Al ser pocos los estudios de dieta de murciélagos frugívoros en el bosque seco tropical, nuestro objetivo fue describir su dieta y analizar cuál es su efecto sobre la germinación de semillas. El trabajo se realizó en el Área Natural Única Los Estoraques, Norte de Santander, Colombia; una zona de vida de bosque seco premontano (bs-PM). Para la captura de murciélagos se utilizaron redes de niebla y se recolectaron sus excretas. Las semillas de Vismia baccifera y Piper sp4, obtenidas de las excretas, fueron seleccionadas para el experimento de germinación cuya respuesta se analizó mediante el índice de capacidad de germinación. Se hizo una curva de acumulación para describir la riqueza de semillas, se calculó el índice de mejor dispersor DII y el índice de Morisita para estudiar solapamiento de dieta. Se registraron diez especies de murciélagos con siete registros nuevos para un total de 18 en la zona, trece de ellas fueron frugívoras. Carollia brevicauda fue la especie más abundante y la mejor dispersora, considerándola clave para la mayoría de las especies vegetales. Se identificaron 18 morfoespecies de semillas, incluyendo Calycolpus moritzianus, nuevo registro en la dieta de los murciélagos. En ninguna de las dos especies de plantas se encontraron diferencias en la germinación de semillas obtenidas de las excretas y aquellas extraídas del fruto directamente. ABSTRACT The study of bat diets is important to understand how their assemblage is shaped and how they can contribute to the dynamics of the forests. Since there are few studies on the diet of fruit bats in the tropical dry forest, our objective was to describe their diet and to understand their effect on seed germination. The work was carried out in the Área Natural Única Los Estoraques, Norte de Santander, Colombia, corresponding to a premontane dry forest life zone (bs-PM). Mist nets were used to capture bats; their excreta were also collected. The seeds of Vismia baccifera and Piper sp4, obtained from the excreta, were selected for the germination experiment whose response was analyzed by means of the germination capacity index. An accumulation curve was made for the seeds richness, the best disperser index DII and the Morisita index were calculated to study diet overlap. Ten species of fruit bats were recorded from which seven are new local records for a total of 18 species in the area, thirteen of these were frugivorous species. Carollia brevicauda was the most abundant and the best disperser species, considering it key for the dispersal of most plant species. A total of 18 seed morphospecies were identified, including Calycolpus moritzianus, being a new record for the diet of bats. We did not find differences in the germination of seeds of the two plant species obtained from either the excreta of from the fruit directly.

This chapter encompasses a literature survey and strategic analysis to understand the elaboration and implementation of Participatory Forest Management (PFM) in Benin, with a focus on the case of the “Forêt des Trois Rivières”. By analyzing the historical background of forest management systems in Benin, we highlighted two major turning points. The first relates to the creation and autocratic management of protected forests, which took place from 1940 to 1990. The second change took place after the Rio conference in 1992, and this emphasized the importance of local communities in natural resources management. Moreover, the results of our strategic analysis of stakeholders involved in the specific case of Participatory Forest Management Plan (PFMP) of the “Forêt des Trois Rivières” showed that it is important to emphasize on active community participation while designing a participatory management plan and for decision making at the implementation stage. We also observed that alliances between foresters and timber loggers are likely to hinder the achievement of the PFM objectives.

Tropical dry forests (TDFs) are characterized by pronounced seasonality in precipitation, with several months of prolonged drought, 80% of annual precipitation occurring during a four- to six-month rainy season, and high interannual rainfall variability. Surprisingly, there are relatively few studies addressing patterns of functional trait in tropical dry forest (TDF) ecosystems. Functional trait analysis across plant species and the environment is a rapidly developing research field with many possible applications for forest restoration practice. Trait-based ecological research within TDFs will advance our understanding of how these ecosystems interact with and differ from other tropical ecosystems.

Forest degradation is attributed to the excessive use of forest resources and extraction, whether for subsistence or commercial purposes. With an increase in human population pressure on forests, forest degradation is becoming a concern for the conservation of biodiversity. The high human dependence on tropical dry forests underscores the need for a complete understanding of the interaction of humans and these forests to ensure their persistence and the wellbeing of the people who depend on these resources. This chapter examines forest resource use and degradation to provide a nuanced understanding of forest degradation and the impact of forest resource use.

Una evaluación del aprovechamiento de Bonellia sprucei Mez como producto forestal no maderable se realizó en las localidades de Las Peñas y Soledad de la localidad de Julcuy, para conocer sobre el aprovechamiento y potencialidades de uso de los Productos Forestales No Maderables derivados de esta especie. Se realizaron recorridos de campo, entrevistas y charlas, así el objetivo del trabajo consistió en evaluar el aprovechamiento de Bonellia sprucei Mez, en las localidades antes mencionadas, a través del método empírico de encuestas y la realización de un muestreo aleatorio estratificado; para el muestreo se establecieron transectos de 20 m x 50 m. Mediante un inventario florístico en el bosque seco tropical de aquellas localidades, se comprobó el grado de asociación de ese taxa con otras especies, así mismo se determinó su abundancia, los porcentajes, cantidad de uso y sus derivados. Los resultados revelan la composición del ecosistema, y demuestran que estos productos no se explotan al máximo. La distancia de los árboles a las viviendas es una variable que incide en el precio final del producto.

We provide species lists and geographical occurrence records of the beetle family Passalidae for three subregions of the department of Sucre, northern Colombia. The sampling localities are lowland environments with typical tropical dry forest vegetation. We selected 15 sampling sites and examined decomposing trunks. We record seven species, four genera, and two tribes of Passalidae. The most abundant species were Passalus punctiger Lepeletier & Serville, 1825, P. interstitialis Eschscholtz, 1829, and P. interruptus (Linnaeus, 1758). We also provide new records for Passalus punctatostriatus Percheron, 1835, Paxillus leachi MacLeay, 1819, and Popilius marginatus (Percheron, 1835) in the department of Sucre. Veturius aspina Kuwert, 1898 was present only in the localities with well-preserved forests. Finally, the species number recorded in this study is low compared to other inventories in Neotropical regions.

Aims: Plant phenology is a tool to assess climate variability, but less is known about the differences in phenological sensitivity at community, life-form and individual species level. The aim of the present study is to know the contribution of individual, life-form leaf phenophases within the community. Methodology: The leaf phenology of tropical dry forest trees in Bhadra wildlife sanctuary, Karnataka, India was observed during June 2004 to May 2009. A total of 277 trees belonging to 45 species were monitored on monthly basis for different phenophases of leaf phenology. Simple Spearman’s correlations and multiple regressions were performed between different phenophases and environmental factors like rainfall and temperature. Seasonality was determined with circular statistics analyses using the phenological variables and dates of observation. Results: The influence of temperature was stressed with multiple regressions. Seasonality of each of the phenophases was also tested with circular statistics. There is a strong seasonality observed in all phenophases, the strength of seasonality was highest with leafless phenophases. Leafing phenophases among some dominant species within the community was described for seasonality and differences among them were also analyzed. Understorey species had longer leaf life span compared to canopy species. At the community level different phenophases are distinctly seasonal, though the strength of seasonality varied considerably with flushing and expansion of leaves, the strength of the seasonality was high with leaf senescence for all species. Conclusion: The results of this research are in agreement with previous study but the present study suggests that community, population and individual sensitivity might vary under the present context of increasing climatic variability and their adaptation helps to understand the climatic influence in shaping phenology at individual, species and community level.

Galictis vittata is a small carnivore distributed in all the natural regions of Colombia, but it is considered as a “demographic rarity” due to its low density throughout its range in the national territory. This note documents new records with some ecological data and compiles the existing evidence about the local distribution of G. vittata in the department of Sucre, Colombian Caribbean. The new records are the product of fieldwork aiming at evaluating mammal diversity in the region, among other ecological aspects, by applying camera-trapping and interviews. In addition, other confirmed records of the species in the department were compiled based on the available information in three online data portals. The new records of G. vittata presented include a camera-trap record in a disturbed area of tropical dry forest and one related to an event of attack by domestic dogs. The local distribution of the species is extended to the sub-regions of Golfo de Morrosquillo and San Jorge, based on that three preserved specimens confirm its presence in the Montes de Maria sub-region. This is among the first data compilation of G. vittata focused specifically to the department of Sucre, also confirming its current presence in disturbed zones of tropical dry forest. The new records contribute evidence to previous statements about the potential ecological tolerance of the species to landscape modifications and provide novel information on possible threats and habitat use, specially about the potential importance of some elements in fragmented landscapes.

The Big Crested Mastiff Bat, Promops centralis (Thomas, 1915), is widely distributed from Mexico to South America but has yet to be reported in the state of Sinaloa, Mexico. We collected 122 acoustic recordings of P. centralis from tropical dry forest and agroecosystems in Sinaloa and Sonora for two years (2015 and 2016). We documented a new record for P. centralis outside the known distribution area in northwestern Mexico. Our results reveal that the current P. centralis distribution needs to be reevaluated.

Management of tropical dry forests in Brazil expanded 450% in the two latest decades; but little is known about the dynamics of these areas. Thus, the objective of this work was to evaluate if the recovery of mean original biomass stocks (MOBS) is a consistent criterion to define cut cycles in a managed forest for charcoal production, and determine the remaining biomass and its contribution to soil carbon stocks. The study was conducted at the Ramalhete Settlement, in General Sampaio, CE, Brazil, in 2018. The explorable shrubby-arboreous biomass (ESAB) and the ESAB mean annual increases (ESAB-MAI) were determined in five areas subjected to clearcutting after 3, 5, 8, 11, and 15 years, and in a preservation area with 40 years of regeneration. Each area was divided into seven plots (20 × 20 m), totaling 42 plots. The ESAB of the plots were compared and the remaining biomass (branches, stumps, and litterfall) in a recently explored area was calculated and converted into organic carbon. The remaining biomass of branches had higher contribution to soil carbon stocks, followed by the litterfall, and stumps. The carbon stocks of the branch component were 3.4-fold higher than those of the litterfall. The recovery of the MOBS of an area after clearcutting should not be used as a criterion to define the cut cycle, since these original carbon stocks do not represent the maximum ESAB production possible in the area; the biodiversity and amount of ESAB in the classes of larger diameter are more adequate criteria. O manejo florestal na floresta tropical seca do Brasil expandiu em 450% nas duas últimas décadas; mas pouco se sabe da dinâmica nessas áreas. Assim, em uma área manejada para produção de carvão, objetivou-se avaliar se a recuperação dos estoques originais médios de biomassa (EOMB) é um critério consistente para definir ciclos de corte, além disso, determinou-se a biomassa remanescente e seu potencial de aporte de carbono ao solo. O estudo foi realizado no Assentamento Ramalhete, General Sampaio-CE, no ano de 2018. Determinou-se a biomassa arbustiva-arbórea explorável (BAAE) e o incremento médio anual (IMA) em cinco talhões submetidos ao corte raso há 3, 5, 8, 11 e 15 anos, e reserva legal (40 anos em regeneração). Em cada talhão foram instaladas sete parcelas (20,0 m x 20,0 m), totalizando 42 parcelas amostrais. Comparou-se a BAAE com a de projeto e calculou-se a biomassa remanescente (ramos, cepas e serapilheira) em um talhão recém explorado, a qual foi convertida para carbono orgânico. Quanto à biomassa remanescente, a ordem de maior potencial de aporte de carbono ao solo foi ramos > serapilheira > cepas. O aporte oriundo do componente ramos é superior ao da serapilheira em 3,4 vezes. A simples recuperação dos EOMB de um talhão após o corte raso não serve como critério para se definir um novo ciclo de corte, pois esses estoques originais não representam a máxima BAAE possível para essa área; sendo a biodiversidade e a presença de mais BAAE nas classes de maior diâmetro critérios mais adequados. &nbsp

Introduction: Scattered trees from tropical dry forests (TDF) deposit significant amounts of leaf litter into pasture soils. Objective: To estimate the litterfall production during the dry season by scattered Lysiloma acapulcense (Kunth) Benth. and Vachellia pennatula (Schltdl. & Cham.) Seigler & Ebinger trees in pastures. Materials and methods: Ten scattered trees of each species were selected from a 10-ha pasture, and litter was collected during the dry season (November to May) and sorted into fractions. Leaf litter biomass, nitrogen (N) and lignin (L) content, and the lignin-nitrogen (L/N) ratio were assessed. Leaf litterfall was modelled over an annual cycle using a double logistic model. Means from all variables were compared between species using a t-test. Results and discussion: Litter, nitrogen and lignin content were similar between species. However, the L/N ratio was significantly higher (P Conclusion: The quantity and quality of leaf litter that scattered trees deposit in a pasture encourages the adoption of agroforestry systems, including tree species native to TDF

Aim The objective of this study is to estimate the current potential geographic distribution of Plebeia flavocincta and to evaluate the influence of climate on the dynamics of suitable habitat availability in the past and in the future. Location Northeast region of Brazil and dry forest areas. Methods The habitat suitability modeling was based on two algorithms, two global circulation models, and six different scenarios. We used this tool to estimate the areas of occurrence in the past (Last Interglacial and Last Glacial Maximum), in the present, and in the future (years 2050 and 2070). Results According to the models, P. flavocincta had great dynamics in the availability of suitable habitats with periods of retraction and expansion of these areas in the past. Our results suggest that this taxon may benefit in terms of climate suitability gain in Northeast Brazil in the future. In addition, we identified high‐altitude areas and the eastern coast as climatically stable. Conclusion The information provided can be used by decision makers to support actions toward protecting and sustainably managing this taxon. Protection measures for this taxon are particularly important because this insect contributes to the local flora and, although our results indicate that the climate may favor this taxon, other factors can negatively affect it, such as high levels of habitat loss due to anthropogenic activities., We analyzed the influence of climate on the dynamics of suitable areas and presented priority areas for the conservation of a stingless bee, an important pollinator in the endemic and threatened dry forest biome distributed across northeastern Brazil. Yellow areas represent locations indicated by all scenarios as suitable for the species considering (a) past, present, future and (b) present and future climate conditions.

Se analiza una comunidad de hormigas encontrada en un fragmento de Bosque Seco Tropical de la Vereda El Arenoso del municipio de Rivera, Huila; el cual se encuentra altamente intervenido pero que aún conserva suficiente estructura de vegetación. Nuestro objetivo principal era determinar si hay significancias en la diversidad de hormigas dentro del área de estudio. Para lograr dicho objetivo se caracterizaron las muestras colectadas tanto de hormigas como de vegetación para analizar su relación. Se registraron un total de 18 géneros de hormigas en todo el fragmento y 16 géneros de plantas. Se encuentra dominado taxonómicamente por las subfamilias Myrmicinae, Ponerinae, Dolichoderinae, Dorylinae, Formicinae, Pseudomyrmecinae para hormigas y Anacardiaceae, Cactaceae, Piperaceae, Nyctageaceae, Myrtaceae, Apocynaceae, Sapindaceae, Aristolochiaceae, Poaceae, Salicaceae, Asteraceae, Moraceae, Boraginaceae, Rutaceae y Euphorbiaceae para plantas.

Resumen Los análisis post incendio, como el índice de área quemada (IAQ), permiten discriminar áreas afectadas y severidad de los incendios forestales. En este estudio se comparó según la frecuencia de incendios, el comportamiento anual del IAQ en la región de bosque seco tropical del Área de Conservación Guanacaste, Costa Rica entre los años 1997 al 2019. Los resultados evidencian que las áreas frecuentemente quemadas por incendios forestales muestran un comportamiento diferenciado en el IAQ a lo largo de todos los años. Mostrando una relación directa entre la frecuencia de incendios forestales y los valores de IAQ. Donde a mayor frecuencia de incendios forestales, los valores de IAQ son mayores. Por otro lado, las áreas que han sido poco afectadas o no han sido afectadas del todo mostraron valores bajos de IAQ. Estos resultados podrían validar la hipótesis de que después de dos a tres incendios, el banco de semillas es completamente destruido. Esto debido a que la composición y estructura de los bosques secos tropicales cambia considerablemente después de múltiples incendios. Abstract Post-fire analysis such as the burned area index (BAI) allows us to discriminate affected areas and the severity of fires. In this study, the annual behaviour of the BAI was analyzed in the tropical dry forest region of the Guanacaste Conservation Area, Costa Rica among 1997 to 2019 according to the frequency of fires. Our results show that the areas frequently burned by forest fires display a differentiated behaviour in the BAI throughout the years. Where, the greater the frequency of forest fires is, the higher the BAI values. On the other hand, areas that have not been affected or have been affected by a single fire showed low BAI values. These results could validate the hypothesis that after two to three fires, the forest seed bank is destroyed. Consequently, the composition and structure of tropical dry forests change considerably after the occurrence of many fires.

espanol[Introduccion]: En las regiones secas de Centroamerica, los ganaderos llevan su hato a los bosques de sus fincas durante la temporada seca, pero se sabe poco sobre esta practica. [Objetivo]: Determinar la frecuencia de esta practica, y como se ajusta al manejo de fincas. [Metodologia]: Se administraron 43 entrevistas semiestructuradas a ganaderos del canton de Liberia, Guanacaste, Costa Rica. [Resultados]: Los ganaderos padecian de la perdida de rentabilidad de la ganaderia debido a sequias, incendios y robo de ganado. El ramoneo en bosques se usaba en el 70 % de las fincas, mayormente entre marzo y mayo. No se pudo asociar esta practica con un tipo especifico de finca o estrategias de alimentacion. La alta variabilidad en manejo de finca impidio explicar las diferencias en practicas de alimentacion. Se encontraron diferencias en la estructura y tipos de alimentacion entre fincas de bajura y en las pendientes de montanas. La decision de usar el bosque para ramoneo parecia basarse en un trade-off entre bienestar animal y facilidad de manejo. El conocimiento de los finqueros sobre el comportamiento del ganado en bosques era variable y limitado a los margenes del bosque y pasturas. [Conclusiones]: Se destaca que los bosques se deben considerar cuando se estudia la ganaderia en regiones secas de Centroamerica. Recomendamos estudios de seguimiento sobre estrategias de alimentacion y sobre el impacto del ganado sobre la integridad ecologica de los bosques secos, para determinar si los decisores de politica deben fomentar este tipo de alternativas de bajo costo. English[Introduction]: In the dry regions of Central America, forests in cattle ranches are used as a refuge for cattle during the dry season, and there is no much information about this practice. [Objective]: to determine the frequency of this practice and how it fits in farm management. [Methodology]: We conducted semi-structured interviews with cattle ranchers in 43 farms in Liberia County, Guanacaste, Costa Rica. [Results]: Cattle farmers suffered from the loss of profitability due to droughts, fire, and cattle theft. Cattle browsing in the forest was used by 70 % of farms, mostly between March and May. No type of farm or feeding strategy was associated with forest browsing. The high variability in farm management did not provide a distinct classification of feeding strategies. We found a difference in farm structure and feed types between ranches in the plains and mountain slopes. The decision to use forests for browsing seemed to rely on a trade-off between animal welfare and ease of management. Traditional knowledge about cattle behavior in forests was variable and often limited to forest edges and pastures. [Conclusions]: This research shows that forests should be taken into consideration when analyzing cattle ranching in dry regions of Central America. We recommend a further study on feeding strategies and the impact of cattle on forest integrity to determine if agricultural policymakers should foster these low-costs alternatives. portugues[Introducao]: Nas regioes secas da America Central, os criadores de gado levam seu rebanho aos bosques de suas fazendas durante a temporada seca, mas pouco se sabe sobre a pratica. [Objetivo]: Determinar a frequencia desta pratica, e como se ajusta ao manejo das fazendas. [Metodologia]: Foram realizadas 43 entrevistas semiestruturadas com criadores de gado da regiao de Liberia, em Guanacaste, Costa Rica. [Resultados]: Os criadores de gado passavam por perdas de rentabilidade do gado devido as sequias, aos incendios e aos roubos do rebanho. O remanejo nos bosques era usado em 70 % das fazendas, em sua maioria entre marco e maio. Nao foi possivel associar esta pratica com um tipo especifico de fazenda ou estrategias de alimentacao. A alta variabilidade no manejo de fazenda impediu explicar as diferencas em praticas de alimentacao. Foram encontradas diferencas na estrutura e tipos de alimentacao entre fazendas costeiras e nos declives de montanhas. A decisao de usar o bosque para o remanejo parecia estar baseada em um trade-off entre o bem-estar animal a facilidade de manejo. O conhecimento dos fazendeiros sobre o comportamento do gado em bosques era variavel e limitado as margens do bosque e pastagens. [Conclusoes]: Destaca-se que os bosques devam ser considerados ao estudar a pecuaria em regioes secas da America Central. Recomendamos estudos de seguimento sobre estrategias de alimentacao e sobre o impacto do gado sobre a integridade ecologica dos bosques secos e, assim, determinar se os decisores politicos deveriam fomentar este tipo de alternativas de baixo custo.

Dalea es el único género de la tribu Amorpheae (Leguminosae: Papilionoideae) presente en Colombia. El género comprende 172 especies, de las cuales cinco se encuentran en bosques y matorrales secos del país. Se presenta el tratamiento taxonómico de Dalea para la flora de Colombia, realizado a partir de trabajo de herbario, de campo y de laboratorio. Se incluye una clave de identificación, seguida de las descripciones y notas relacionadas con el hábitat y la distribución geográfica de todas las especies. A la vez, se reevalúan los caracteres diagnósticos de D. cuatrecasasii, y se designa un neótipo para D. coerulea.

We report the predation on the gecko Hemidactylus angulatus by the spider Ancylometes bogotensis, in the Tropical Dry Forest life zone located at Northern Tolima (Colombia). This short note is a contribution to the knowledge about the natural history of the referenced species because of the potential of A. bogotensis as a biological control agent of geckos that decreases its invasive potential. This is important due to the possibility to make populations of the gecko decline and to restrict the entry of these saurians to natural forested areas.

Societal Impact Statement Tropical dry forests (TDF) underpin the wellbeing of millions, mostly rural populations; yet have suffered from severe clearing in Colombia, triggering cascading effects such as desertification. By engaging scientists, society, and institutions in the establishment of platforms for monitoring biodiversity and ecosystem functioning, crucial knowledge gaps will be bridged, helping to find a path toward sustainable development. Science‐led but socially and economically anchored information on biodiversity will help to incorporate nature's contributions to people into the society's cultural values. Ultimately, these transformative actions will translate into the comprehensive management of TDF through a greater impact in decision making. Summary Thousands of permanent plots have been established across the tropics with the purpose of monitoring tree communities. Research outcomes from these platforms, however, have been mainly directed toward the academic community, and their contribution to society has been limited so far. Here, we show how generating robust data on biodiversity has supported decision making in Colombian tropical dry forests (TDF), where less than 8% of their original cover remains. As a first step to build a national dialogue around the critical status of this ecosystem, a national collaborative network on TDF research and monitoring was born in 2014, the Red de Investigación y Monitoreo del Bosque Seco Tropical en Colombia (Red BST‐Col). Our main goal is to generate scientifically sound information that feeds into the comprehensive management of this ecosystem. To do so, a set of biodiversity monitoring platforms has been established across the country, which have already served to answer socio‐ecological questions related with deforestation drivers, citizen science, or the valuation of ecosystem services. Overall, this research agenda has nurtured the four lines that underpin the Program for the comprehensive management of dry forests in Colombia (knowledge management, preservation, restoration, and sustainable use), formulated by the Humboldt Institute, the United Nations Development Programme, and the Ministry of Environment in 2019. Many challenges are ahead, however, for a complex territory where multiple social actors and productive sectors coexist. The ultimate goal is to integrate all the dimensions of biodiversity to achieve a synthetic understanding of the functioning of the most endangered ecosystem in Colombia, and its relationship with local communities' wellbeing.

With the objective to contribute to a better understanding of ecological consequences of deforestation on the below-ground system in the Western Llanos of Venezuela, we evaluated the vertical distribution, nutrient concentration and seasonal changes of total fine root mass (FRM) (0.05) were observed in the total concentrations of organic carbon, nitrogen, phosphorus, calcium and magnesium in the FRM in soils supporting forest, OP and YP at the evaluated depths. Non-significant changes in the total FRM and nutrient concentrations were observed between the sampling periods and the 3 study sites. YP soils showed a slight increase in FRM that could be associated with the root growth of secondary vegetation, which is considered a weed and is periodically removed. Our results suggest that the land use change from tropical forest to pastures has not significantly affected the mass of fine roots and their carbon and nutrient concentrations. Further studies are needed to determine if these findings apply to other ecosystems.

Aims: Percentage of native thorny and thornless Mimosa tenuiflora (Willd.) Poiret trees, and their growth, height and/or diameter class distribution and clustering pattern were determined in a pure stand of this species. Study Design: A survey of the adult and juvenile plants was carried out in a 50 m x 50 m site after 10 years of tree cover regeneration. Place and Duration of Study: The study site was located at Fazenda Nupearido, Patos-PB, Brazil and data collection occurred in September 2017. Methodology: Adult plants with trunk circumference at breast height (1.3 m from the soil) > 6 cm (CBH > 6 cm) were measured for height and CBH, and located within the study area. Juvenile plants (i.e.: CBH ≤ 6 cm) were divided into 4 height classes. The position of only the thornless individuals within the study area was determined. Results: Among the 170 adult plants documented in the area, 95.3% and 4.7% were thorny and thornless, respectively. Height and diameter at breast height averaged higher for thornless than for thorny adult plants (4.13 m and 9.28 cm vs. 3.61 m and 5.90 cm). In contrast, thornless juvenile plants averaged lower for height and basal diameter than the thorny ones. The number of juvenile M. tenuiflora totaled 897 plants, including 58 thornless ones, but percentage of thornless juveniles peaked at 17.6% for 10-to-50 cm high plants. In general, thorny plants showed a clustering pattern of distribution while the thornless plans were randomly distributed. Conclusion: The density, random distribution and growth of the thornless plants suggest the possibility to form thickets of thornless plants in caatinga sites where this tree predominates. Also, these data show that in forested sites with thorny trees that generate thornless mutants, as observed in the Caatinga Biome for M. tenuiflora and other tree species, it is possible to increase the frequency and abundance of the naturally regenerating thornless plants, making easier the exploitation of forest resources, an approach that may be applied in other types of vegetation.

Avocado Branch Dieback and Wilting (ABDW) was recently reported on West-Indian avocado (Persea americana var. americana) orchards in the Serrania de Perija, Colombia. This disease is caused by Bionectria pseudochroleuca and transmitted by ambrosia beetles. In this work we estimated the potential distribution of ABDW to map avocado-growing areas at risk of ABDW in Colombia and Venezuela. Disease occurrence records were obtained from pest and disease surveys undertaken during 2014–2015 period in the avocado-growing areas of the Colombian Caribbean. The correlative maximum entropy-based model (MaxEnt) algorithm was used to assess the potential distribution of ABDW in the Caribbean South America. The MaxEnt model predicted locations with potential distribution for ABDW disease in tropical dry forest biomes of Colombia and Venezuela. The largest producing avocado areas in these locations are Serrania de Perija (Colombia) and Serrania de Merida (Venezuela). Field reports from these locations confirm the presence of avocado trees with symptoms of wilting and branch dieback in association with ambrosia beetles. Isothermality, mean diurnal range in temperature and precipitation of the wettest month were the variables with the highest contribution and importance to the spatial distribution model of ABDW disease. A potential distribution map of the ABDW disease for the Caribbean South America was proposed together with an explanatory hypothesis for disease occurrence.

Functional diversity is a tool for understanding biological communities and the influence of environmental filters on assembly rules. However, few studies explore the relationships of diversity metrics across contrasting ecosystems. We evaluated the effect of ecosystems (tropical dry forest and pine-oak forest) and seasons (wet and dry) on the functional diversity and community composition of amphibians in western Mexico. Our study showed that associations among metrics of diversity were not constant across contrasting ecosystems. The amphibian communities were related to changes in the environmental variables of elevation, temperature and relative humidity. We analyzed the functional diversity of the amphibian community based on 11 traits related to reproduction, trophic flow and habitat use. Seven functional groups with distinct ecological characteristics were detected, of which, four presented functional redundancy and two were represented by a single species. While the tropical dry forest during the wet season showed the highest species richness, the richness and diversity of functional groups were significantly lower than in the pine-oak forest in both seasons. These results suggest that the seasonal drought in the tropical dry forest could act as an environmental filter, promoting dominance of similar functional traits among species, while limiting similarity could be acting in the pine-oak forest, in the face of relatively stable hydric conditions, allowing a greater functional diversity. Analysis of the relationship between biological communities and ecosystem functioning is necessary to undertake conservation strategies.

This paper shows the intraspecific plant responses in leaf morphology, herbivory and FA between mature and successional tropical dry forests, as well as the difficulty associated with understanding the relationship between FA and herbivory Understanding the processes that affect biotic interactions during secondary succession has implications for the maintenance of species diversity in the tropics. We studied the changes in leaf morphology, fluctuating asymmetry (FA) and herbivory in three dominant tropical dry forest plant species that occur in mature and secondary forests. We selected eight study sites: four in mature and four in successional forests. At each site, a plot of 20 × 50 m was established to characterize the vegetation structure and soil fertility. Subsequently, leaf morphology, FA and herbivory were measured in all individuals of Cordia elaeagnoides, C. alliodora and Achatocarpus gracilis with DBH ≥ 2.5 cm found in the plots. Plant abundance and plant height decreased in secondary forest, while the content of nitrates and phosphates increased in soil of secondary forests. Differences in leaf morphology between forest conditions were found for the three species. Total leaf area was higher in mature than in secondary forests for C. elaeagnoides and A. gracilis. An opposite pattern was found for C. alliodora. In both Cordia species, herbivory was higher in secondary than in mature forests. The opposite pattern was found for A. gracilis in secondary forests. For all the cases, FA was higher in mature forests than in secondary forests. Herbivory was positively correlated with FA in secondary forests in C. elaeganoides and in A. gracilis, whereas in C. alliodora herbivory was positively related with FA in mature forests. Overall, we detected changes in foliar morphology, fluctuating asymmetry and herbivory between mature and secondary forests, with a general pattern of higher FA levels in mature forests. Our findings illustrate the difficulty associated with understanding the relationship between FA and herbivory throughout the regeneration process in tropical dry forests due to the complexity of abiotic and biotic factors that can affect plant–herbivore interactions.

We describe and illustrate a new species of Capparidastrum subgen. Pulviniglans (Capparaceae). Capparidastrum dugandii occurs in tropical dry forest fragments of the Colombian inter-Andean valley of the Dagua River, near the municipality of Santa Fe de Antioquia. Capparidastrum dugandii is distinguished from other species of subgen. Pulviniglans molecularly and by the lowest number of stamens (18–20). In addition, the species is endemic to the Cauca biogeographic province.

Understanding the factors that influence the composition and structure of bee communities in natural habitats is critical for conservation and restoration efforts, mainly in disturbed ecosystems that are widely used for agricultural crop production, such as tropical dry forests (TDF). The aim of this study was to evaluate the effects of tree species composition and vegetation structure on the composition, abundance and species richness of eusocial and non-eusocial wild bee assemblages. Bees (19.909 individuals of 96 species) were collected in fifteen plots in different secondary succession stages in a TDF in the state of Minas Gerais, Brazil. We found a positive relationship between tree community similarity and bee community similarity, for both eusocial and non-eusocial bees. Average tree height positively affected the abundance and species richness of eusocial bees, while the abundance of non-eusocial bees was negatively affected by tree species richness. Similar tree species composition and vegetation structure between plots at the same stage of secondary succession probably determined more similar bee communities than dissimilar tree communities. Most eusocial bee species are dependent on cavities in large trees to house their colonies, while most non-eusocial bees probably prefer open habitats because they provide a greater density and diversity of floral resources, and suitable areas for ground-nesting species. Since eusocial bees represented 94% of the individuals sampled, the conservation and restoration of mature forests is of primary importance in order to increase eusocial bee diversity, and the maintenance of these areas in the vicinity of agricultural systems is crucial to increase the ecosystem service of pollination.

Forest soil contributes to global methane (CH4) cycle as the natural sink for atmospheric CH4 by methane-oxidizing bacteria (MOB). In this study, high-throughput sequencing of pmoA gene amplicons based approach was used to investigate temporal variations in molecular diversity of MOB in soil of tropical dry forest. Quantitative PCR (qPCR) analysis revealed pmoA and 16S rRNA gene copy numbers (copies g−1 dws) ranging from 2.23 × 106 to 14.62 × 106 and from 0.92 × 109 to 14.99 × 109, respectively, in the year 2016. In 2017, the respective values varied from 1.96 × 106 to 13.62 × 106 and from 2.55 × 109 to 20.15 × 109, respectively. The sequence analysis revealed the existence of both type I and type II methanotrophs in soils. The average observed OTUs were about 800/sample, and Shannon diversity index ranged between 4.24 and 6.22 being highest in winter season. The rice paddy clusters (RPCs), Methylocystis, Methlylocystis-Methylosinus and JR2 and JR3, dominated the methanotrophic community with relative abundance of 32.7–50.2, 15.4–34.2, 0.45–15.8, 0.0–17.8 and 1.6–19.2%, respectively. Relatively, higher CH4 oxidation potential (MOP) (ng CH4 g−1 h−1 dws) was observed in winter (14.12) compared with rainy (2.10) and summer (3.72) coinciding with high methanotrophic diversity and abundance. Overall, the study suggests that tropical dry deciduous forest soils favour considerable range of methanotrophic diversity and abundance that positively correlates with MOP of soils across season.

Fil: Blanco Torres, Argelina. Universidad Nacional de Colombia; Colombia. Universidad de la Costa.; Colombia

The aim of this study was to evaluate the impact of the creation of protected areas (PAs) to avoid deforestation using Matching methods, focusing on the north of the Minas Gerais state, Brazil. Usi...

Knowledge of the nutritional efficiency of species can help revegetation of forest areas, guiding the use of species that best adapt to environmental humidity, altitude and diversity. The objective of this study was to evaluate the nutrient utilization efficiency of N, P, K, Ca and Mg of dominant species in tropical dry forest and rainforest environments. The work was carried out in two areas, both in Pernambuco state, characterized as: Tropical Dry Forest of Caatinga and Tropical Rainforest of Atlantic Forest. A floristic and phytosociological survey was carried out. Species with highest density were evaluated, four from the dry forest and three from the rainforest. For each species, leaves of five healthy individuals of similar size were sampled and nutrient contents were determined. Leaf biomass was estimated by allometric equations. Rainforest species were more efficient in the use of N and K, and dry forest species in the use of P and K. In the dry forest environment, the species Pilocarpus spicatus and Guapira oposita stored more nutrients, and in the rainforest, the species Dialuim guianese was more efficient. These species are essential for the balance of ecosystems and the continuous and sustainable cycling of nutrients.

To understand the effects of invasive species on soil hydraulic properties is a challenging task for Neotropical dry ecosystems because the relative paucity of knowledge of linkages between functional traits of species in response to drought conditions and land-cover transformation contexts. We tested whether functional strategies vary between native and invasive plants and if these differences have impact on processes at ecosystem level. Eight functional traits in wood and leaves of all woody species reported in our study area were measured. Over two contrasting climatic seasons and three vegetation covers, we measured four water regulation properties of soils. We found that forest covers showed higher values of hydraulic conductivity, water infiltration rate, volumetric water content and lower penetration resistance (lower compaction) of soils for both climatic seasons than other vegetation covers. In contrast, zones dominated by invasive species and degraded covers showed greater similarity between hydraulic properties in the soil and high variation among climatic seasons. Additionally, evergreen and deciduous species were functionally different, and invasive evergreen legumes were characterized by acquisitive hydraulic traits but leaf, height and wood density related with conservative strategies. The dominance of functional traits, mainly hydraulic traits, was correlated with volumetric moisture content of the soil. The functional differences between invasive and native species explained the lower soil moisture and greater soil compaction values in invasive covers compared to the forest covers. These results confirm that introduction of invasive species have an impact on soil ecosystem properties on tropical dry forests. Additionally, it is possible that invasive species can help to recover some hydraulic properties and can facilities the restoration processes in degraded areas where the native species failed to colonize.

In Brazil, the Caatinga ecoregion is the only biome that lies completely within the country, covering approximately 11% of the national territory. This biome exhibits a strong climatic seasonality ...

Landscape Ecology using GIS is applied to understand the effects of forest fragmentation and makes it feasible mainly for extensive areas, through the possibility of analyzing both the variety of units that compose it in time. This study aims to analyze the land use and coverage of tropical dry forests and to characterize their landscape structure in an area of the municipality of Floresta, Pernambuco, Brazil, in order to understand how the landscape configuration can influence the conservation. Orbital images were used from LANDSAT, and the classification was performed in the QGIS 2.18 software using the Maximum Likelihood methodification, for the years of 2007 and 2017. A circular buffer was incorporated around the area of study to analyze the structural patterns in the context of the landscape. Five thematic classes were used: dense vegetation, sparse vegetation, exposed soil, grassland, and water. The metrics were obtained through the Patch Analyst tool only to the class of dense vegetation. It is noted that much of the dense vegetation has become sparse. There was a reduction of exposed soil and an increase in grassland areas, which may indicate a regeneration process of the vegetation. The fragments of dense vegetation with more substantial dimensions are on constant exploratory actions and are the most affected with the reduction of size. Furthermore, climatic factors, periods of drought, and the presence of livestock may also affect the fragmentation of dense vegetation patches. Therefore, the landscape became heterogeneous, and a tendency was observed to increase the fragmentation, mainly in the more significant spots.

Cathemeral primates perform significant amounts of activity during the daylight and dark portions of the 24-h cycle. Most brown lemurs have been reported to be cathemeral. A previous study reported that brown lemurs in Ankarafantsika National Park (ANP) shift their activity pattern from being cathemeral in the dry season to being diurnal in the wet season. From July 2015 to March 2016, we collected data on active behaviour of brown lemurs over 46 full-day and 33 full-night observations, distributed evenly between the dry and wet seasons. This study examined the abiotic factors that potentially allow this seasonal shift from cathemeral to diurnal activity. We analysed the effects of day length (time from sunrise to sunset), nocturnal luminosity, and climatic factors on the diurnal and nocturnal activities of the brown lemurs in ANP using generalized linear mixed models. We found that the brown lemurs were cathemeral regardless of season. Their diurnal activity increased with increasing day length and at high humidity, but decreased on days of high temperature and low lunar luminosity. Their nocturnal activity increased with decreasing day length, during bright nights, at low temperature, and at low humidity. Their diurnal and nocturnal activities decreased during heavy rainfall. These data indicate that the photoperiodic variation entrained their activity rhythm. Bright nights may provide better visibility, advantageous for the detection of predators and food, although it may increase exposure to predators. The modification of activity level with temperature variation can be a behavioural thermoregulation. The high humidity during the wet season probably reduced evaporative cooling, inducing increased body temperature and stimulating water foraging as a potential response to dehydration and active heat dissipation. Investigation on physiological responses to environmental factors is needed to fully understand cathemerality in lemurs. These findings emphasize the flexibility of diurnal and nocturnal activity level of brown lemurs according to the great seasonal variation in tropical dry forests.

We report the first record of Eptesicus innoxius in northwestern Ecuador, in the province of Esmeraldas, occurring in a disturbed area, at 134.3 km northwest from the nearest known locality in Ecuador, which represents an important latitudinal extension in the distribution of this species. A predictive distribution model is presented using a total of 43 records from localities of Ecuador and Peru, and its distribution area is determined by a minimum convex polygon (PMC). The sensitivity value obtained in the test data was 0.984 and the area under curve ROC (AUC) value obtained (0.979) indicates an acceptable confidence level. Based on new records and known records, we estimate its distribution area in 135,243 km2. The environmental variables with the greatest influence in the distribution of E. innoxius were: Precipitation seasonality (37.4 %), Minimum temperature of coldest month (20.1 %), Precipitation of driest month (14.5 %), and Mean temperature of wettest quarter (12.8 %). This data show that E. innoxius has been recorded mainly in tropical dry forest, but also has presence in humid areas. Within these new reports, we recommended an upgrade of its conservation status in Ecuador and Peru.

Geographic variation in acoustic signals may arise in vocal learning species due to processes of cultural evolution and population dynamics, but few studies have evaluated geographic vocal variatio...

Tropical dry forests are diverse ecosystems that are globally threatened but are rarely protected. The main threat to this habitat is conversion for agricultural use. Here we evaluate the effects o...

The objective of this study was to evaluate the influence of the composition and diversity of plant species browsed in a tropical dry forest, on the selection and voluntary intake (VI) by cattle during two seasons of the year. Plant species selection and VI of nine adult cattle (390 ± 13 kg of live weight) was evaluated for 7 weeks during the dry and rainy seasons on secondary vegetation (acahual). The composition, structure, diversity and importance value index were measured for fodder species browsed by cattle. The bite frequency (BF), preference index (PI) and VI of plants were also recorded. A total of 4882 plants belonging to 26 species and 17 families were registered, with a Shannon–Wiener diversity (H′) of 2.45. The species with the highest BF, PI and VI (P

Variation in tree biomass and carbon (C) stocks in tropical dry forests is important at both regional and global scale to know their contribution in global C cycle. In Indian tropical forests, the ...