Lianas Significantly Reduce Aboveground and Belowground Carbon Storage: A Virtual Removal Experiment

Lianas are a quintessential tropical plant growth-form; they are speciose and abundant in tropical forests worldwide. Lianas compete intensely with trees, reducing nearly all aspects of tree performance. However, the negative effects of lianas on trees have never been combined and quantified for multiple tropical forests. Here, we present the first comprehensive standardized quantification of the effect of lianas on trees across tropical forests worldwide. We used data from 50 liana removal experiments and quantified the effect size of lianas on tree growth, biomass accretion, reproduction, mortality, leaf water potential, sap flow velocity, and leaf area index (LAI) across different forest types. Using a three-level mixed-effect meta-analysis, we found unequivocal evidence that lianas significantly reduce tree growth and biomass accretion in ecological, logging, and silvicultural studies. Lianas also significantly reduce tree reproduction, recruitment, and physiological performance. The relative detrimental effect of lianas on trees does not increase in drier forests, where lianas tend to be more abundant. Our results highlight the substantial liana-induced reduction in tree performance and biomass accumulation, and they provide quantitative data on the effects of lianas on trees that are essential for large-scale plant demographic and ecosystem models that predict forest change and carbon dynamics

Estudio exploratorio de variables a través de análisis estructural MICMAC en la prestación del servicio en la administración pública municipal de Monterrey, México

Durante muchos años se ha intentado subsanar las graves deficiencias de la Administración Pública municipal en los países con una economía en transición, como es el caso de México. Situación que a pesar de que la administración pública municipal cuenta con avances en capacitación, modernización y parámetros de medición del servicio, aún tiene graves rezagos sistémicos y problemáticas como: conflicto de intereses, procedimientos lentos, prepotencia e infraestructura deficiente, entre las quejas más recurrentes de los ciudadanos de la ciudad de Monterrey respecto de la prestación del servicio por parte de la administración pública municipal; debido a ello, se realizó un estudio exploratorio de variables a través del sistema MICMAC (análisis estructural), es mediante este estudio que se plantea encontrar las variables más impactantes en las que la administración debería realizar acciones correctivas en la prestación del servicio del municipio de Monterrey, México

Do Lianas Shape Ant Communities in An Early Successional Tropical Forest?

Almost half of lowland tropical forests are at various stages of regeneration following deforestation or fragmentation. Changes in tree communities along successional gradients have predictable bottom‐up effects on consumers. Liana (woody vine) assemblages also change with succession, but their effects on animal succession remain unexplored. Here we used a large‐scale liana removal experiment across a forest successional chronosequence (7–31 years) to determine the importance of lianas to ant community structure. We conducted 1,088 surveys of ants foraging on and living in trees using tree trunk baiting and hand‐collecting techniques at 34 paired forest plots, half of which had all lianas removed. Ant species composition, β‐diversity, and species richness were not affected by liana removal; however, ant species co‐occurrence (the coexistence of two or more species in a single tree) was more frequent in control plots, where lianas were present, versus removal plots. Forest stand age had a larger effect on ant community structure than the presence of lianas. Mean ant species richness in a forest plot increased by ca. 10% with increasing forest age across the 31‐year chronosequence. Ant surveys from forest \u3e20 years old included more canopy specialists and fewer ground‐nesting ant species versus those from forestsConsequently, lianas had a minimal effect on arboreal ant communities in this early successional forest, where rapidly changing tree community structure was more important to ant species richness and composition

La imagen y la narrativa como herramientas para el abordaje psicosocial en escenarios de violencia en el departamento del cesar

El siguiente trabajo académico corresponde a la fase cuatro del diplomado de profundización Acompañamiento Psicosocial en Escenarios de Violencia, ofrecido por la Universidad Nacional Abierta y a Distancia (UNAD) como opción de grado a sus estudiantes de psicología, en este se pretende el reconocimiento de herramientas como métodos de abordaje, específicamente la imagen y la narrativa el cual permite el acercamiento a los contextos que se pretenden reconocer y estudiar. El documento permitirá conocer cada una de las historias identificadas durante la realización del diplomado, mismas que han estado entrelazadas por hechos dolorosos y situaciones que impactaron negativamente en la vida de quienes padecieron el conflicto armado en el departamento del Cesar, pero además enmarca la forma de resiliencia y empoderamiento que estos han adquirido con el único fin de resignificar su vida , la de sus familias, olvidar el pasado y construir a través de la verdad momentos de perdón y reconciliación; Considerando que la esencia del diplomado anteriormente mencionado se basa en la apropiación de constructos y referentes, tanto conceptuales como metodológicos, como lo es por ejemplo el enfoque narrativo, se debe reconocer a este como fuente esencial para la creación de recursos y estrategias que le permitirán a las comunidades desarrollar habilidades de afrontamiento y como fin para la superación de los hechos traumáticos ocasionados por la violencia originada por el conflicto armado en el territorio Colombiano.The following academic work corresponds to phase four of the in-depth diploma course Psychosocial Support in Scenarios of Violence, offered by the National Open and Distance University (UNAD) as a degree option to its psychology students, this aims to recognize tools such as methods of approach, specifically the image and the narrative which allows the approach to the contexts that are intended to be recognized and studied. The document will allow us to know each of the stories identified during the completion of the diploma, which have been intertwined by painful events and situations that negatively impacted the lives of those who suffered the armed conflict in the department of Cesar, but also frames the way of resilience and empowerment that they have acquired with the sole purpose of redefining their lives, that of their families, forgetting the past and building moments of forgiveness and reconciliation through the truth; Considering that the essence of the aforementioned diploma is based on the appropriation of constructs and references, both conceptual and methodological, such as, for example, the narrative approach, this must be recognized as an essential source for the creation of resources and strategies that will allow communities to develop coping skills and as an end to overcoming the traumatic events caused by the violence caused by the armed conflict in Colombian territory

Effect of the inclusion of Bacillus spp. in growing–finishing pigs’ diets: a meta-analysis

This meta-analysis determined the effect of Bacillus spp. on growth performance of growing–finishing pigs and then assessed causes for the heterogeneity of responses detected using meta-regression. A database of 22 articles published from 2000 to 2020 was identified, and 9 articles fitted the selection criteria and were integrated in the final database. Statistical analysis was performed to analyze the effect size for ADG, average daily feed intake (ADFI), and F:G ratio using a standardized means difference (SMD) at a 95% confidence interval. A meta-regression analysis was used to investigate the cause of heterogeneity, using the individual SMD for each study assessment as the outcome and the associated SE as the measure of variance. Dietary Bacillus spp. supplementation had no effect on ADFI (SMD: −0.052, p = 0.138) and numerically increased ADG (SMD: 0.113, p = 0.081) and reduced the F:G ratio SMD: −0.127, p < 0.001). Meta-regression outcomes suggested that the number of animals per group was an essential component promoting heterogeneity in ADG. Overall, the inclusion of Bacillus spp. (median 486 mg/d) in growing–finishing pigs can increase ADG and can decrease the F:G ratio

Edaphic Factors and Initial Conditions Influence Successional Trajectories of Early Regenerating Tropical Dry Forests

Edaphic factors and initial conditions can regulate the speed of forest succession. Edaphic factors, which include soil chemistry and topography, determine soil resource availability and can filter species as forests mature. Initial plant cover early in succession can determine the rates at which secondary forests change in structure, richness, biomass and composition over time. While some of the effects of edaphic factors and initial conditions on forest succession have been studied, how they simultaneously modify young regenerating tropical forest has rarely been examined. We surveyed 22 young forests plots in Panama for 7 years (11, 6 and 3‐year‐old stands when censuses began). We study how tree and liana species composition change early in succession, as well as how edaphic factors (soil nutrients and topography) and initial conditions (initial basal area and forest canopy cover) influence changes in tree and liana abundance, species richness, biomass and composition throughout succession. We found that edaphic factors and initial conditions explained up to 45% of the variation in the successional trajectories for trees and lianas. Soil nutrients had a significant positive effect on the changes in tree biomass accretion, while topography significantly contributed to community similarity of large lianas over time. Initial basal area had a significant negative effect on the changes in sapling abundance and tree richness over time and a positive marginal effect on tree biomass accretion. Forest canopy cover only had a positive marginal effect on changes in sapling abundance. Tree abundance, biomass and richness increased over time, while sapling abundance, biomass and richness remained stable or decreased, probably due to community thinning. However, changes over time of small and large lianas diverged, probably due to differential resource availability that affected lianas but not trees. Synthesis. Soil fertility, topography and initial basal area influence early forest regeneration. Higher soil fertility can allow trees to fix carbon faster, and lianas might show habitat association to ridges and slopes. Basal area can determine how fast saplings and trees change in abundance, richness and biomass over time by possibly affecting space availability for recruitment and light availability for growth

Ensemble Composition and Activity Levels of Insectivorous Bats in Response to Management Intensification in Coffee Agroforestry Systems

Shade coffee plantations have received attention for their role in biodiversity conservation. Bats are among the most diverse mammalian taxa in these systems; however, previous studies of bats in coffee plantations have focused on the largely herbivorous leaf-nosed bats (Phyllostomidae). In contrast, we have virtually no information on how ensembles of aerial insectivorous bats – nearly half the Neotropical bat species – change in response to habitat modification. To evaluate the effects of agroecosystem management on insectivorous bats, we studied their diversity and activity in southern Chiapas, Mexico, a landscape dominated by coffee agroforestry. We used acoustic monitoring and live captures to characterize the insectivorous bat ensemble in forest fragments and coffee plantations differing in the structural and taxonomic complexity of shade trees. We captured bats of 12 non-phyllostomid species; acoustic monitoring revealed the presence of at least 12 more species of aerial insectivores. Richness of forest bats was the same across all land-use types; in contrast, species richness of open-space bats increased in low shade, intensively managed coffee plantations. Conversely, only forest bats demonstrated significant differences in ensemble structure (as measured by similarity indices) across land-use types. Both overall activity and feeding activity of forest bats declined significantly with increasing management intensity, while the overall activity, but not feeding activity, of open-space bats increased. We conclude that diverse shade coffee plantations in our study area serve as valuable foraging and commuting habitat for aerial insectivorous bats, and several species also commute through or forage in low shade coffee monocultures

Impacts of land management and climate change in a developing and socioenvironmental challenging transboundary region

Land-use/cover change is the major cause of terrestrial ecosystem degradation. However, its impacts will be exacerbated due to climate change and population growth, driving agricultural expansion because of higher demand of food and lower agricultural yields in some tropical areas. International strategies aimed to mitigate impacts of climate change and land use-cover change are challenging in developing regions. This study aims to evaluate alternatives to minimize the impacts of these threats under socioeconomic trajectories, in one of the biologically richest regions in Guatemala and Mexico. This study is located at the Usumacinta watershed, a transboundary region that shares a common history, with similar biophysical properties and economic constraints which have led to large land use/cover changes. To understand the impacts on deforestation and carbon emissions of different land-management practices, we developed three scenarios (1): business as usual (BAU), (2) a reducing emissions scenario aimed to reduce deforestation and degradation (REDD+), and (3) zero-deforestation from 2030 onwards based on the international commitments. Our results suggest that by 2050, natural land cover might reduce 22.3 and 12.2% of its extent under the BAU and REDD + scenarios, respectively in comparison with 2012. However, the zero-deforestation scenario shows that by 2050, it would be possible to avoid losing 22.4% of the forested watershed (1.7 million ha) and recover 5.9% (0.4 million hectares) of it. In terms of carbon sequestration, REDD + projects can reduce the carbon losses in natural vegetation, but a zero-deforestation policy can double the carbon sequestration produced by REDD + projects only. This study shows that to reduce the pressures on ecosystems, particularly in regions highly marginalized with significant migration, it is necessary to implement transboundary land-management policies that also integrate poverty alleviation strategies