Developing Allometric Equations for Teak Plantations Located in the Coastal Region of Ecuador from Terrestrial Laser Scanning Data

Traditional studies aimed at developing allometric models to estimate dry above-ground biomass (AGB) and other tree-level variables, such as tree stem commercial volume (TSCV) or tree stem volume (TSV), usually involves cutting down the trees. Although this method has low uncertainty, it is quite costly and inefficient since it requires a very time-consuming field work. In order to assist in data collection and processing, remote sensing is allowing the application of non-destructive sampling methods such as that based on terrestrial laser scanning (TLS). In this work, TLS-derived point clouds were used to digitally reconstruct the tree stem of a set of teak trees (Tectona grandis Linn. F.) from 58 circular reference plots of 18 m radius belonging to three different plantations located in the Coastal Region of Ecuador. After manually selecting the appropriate trees from the entire sample, semi-automatic data processing was performed to provide measurements of TSCV and TSV, together with estimates of AGB values at tree level. These observed values were used to develop allometric models, based on diameter at breast height (DBH), total tree height (h), or the metric DBH2 × h, by applying a robust regression method to remove likely outliers. Results showed that the developed allometric models performed reasonably well, especially those based on the metric DBH2 × h, providing low bias estimates and relative RMSE values of 21.60% and 16.41% for TSCV and TSV, respectively. Allometric models only based on tree height were derived from replacing DBH by h in the expression DBH2 x h, according to adjusted expressions depending on DBH classes (ranges of DBH). This finding can facilitate the obtaining of variables such as AGB (carbon stock) and commercial volume of wood over teak plantations in the Coastal Region of Ecuador from only knowing the tree height, constituting a promising method to address large-scale teak plantations monitoring from the canopy height models derived from digital aerial stereophotogrammetry

Global governance approaches to addressing illegal logging: Uptake and lessons learned

One of the most challenging tasks facing development agencies, trade ministries, environmental groups, social activists and forest-focused business interests seeking to ameliorate illegal logging and related timber trade is to identify and nurture promising global governance interventions capable of helping improve compliance to governmental policies and laws at national, subnational and local levels. This question is especially acute for developing countries constrained by capacity challenges and “weak states” (Risse, 2011). This chapter seeks to shed light on this task by asking four related questions: How do we understand the emergence of illegal logging as a matter of global interest? What are the types of global interventions designed to improve domestic legal compliance? How have individual states responded to these global efforts? What are the prospects for future impacts and evolution? We proceed in the following steps. Following this introduction, step two reviews how the problem of “illegal logging” emerged on the international agenda. Step three reviews leading policy interventions that resulted from this policy framing. Step four reviews developments in selected countries/regions around the world according to their place on the global forest products supply chain: consumers (United States, Europe and Australia); middle of supply chain manufacturers (China and South Korea) and producers (Russia; Indonesia; Brazil and Peru; Ghana, Cameroon and the Republic of Congo). We conclude by reflecting on key trends that emerge from this review relevant for understanding the conditions through which legality might make a difference in addressing critical challenges

Isolation and characterization of the full-length cDNA encoding a member of a novel cytochrome p450 family (CYP320A1) from the tropical freshwater snail, Biomphalaria glabrata, intermediate host for Schistosoma mansoni

Cytochrome p450s (cyp450s) are a family of structurally related proteins, with diverse functions, including steroid synthesis and breakdown of toxins. This paper reports the full-length sequence of a novel cyp450 gene, the first to be isolated from the tropical freshwater snail Biomphalaria glabrata, an important intermediate host of Schistosoma mansoni. The nucleotide sequence is 2291 bp with a predicted amino acid sequence of 584aa. The sequence demonstrates conserved cyp450 structural motifs, but is sufficiently different from previously reported cyp450 sequences to be given a new classification, CYP320A1. Initially identified as down-regulated in partially resistant snails in response to S. mansoni infection, amplification of this gene using RT-PCR in both totally resistant or susceptible snail lines when exposed to infection, and all tissues examined, suggests ubiquitous expression. Characterization of the first cyp450 from B. glabrata is significant in understanding the evolution of these metabolically important proteins

Bats use live fences to move between tropical dry forest remnants

Linear features can benefit wildlife by assisting animal movement. We captured bats along barbedâ wire and liveâ tree fences connecting tropical dry forest patches in Nicaragua. Bat species richness and captures were higher along live fences but we noted differences in sex ratios, richness, and species composition compared to surrounding natural forests.Abstract in Spanish is available with online onlyResumenLa degradación del hábitat y fragmentación del bosque son amenazas para la biodiversidad a nivel mundial. Estructuras lineales pueden beneficiar la vida silvestre, al asistir movimiento de animales entre parches de hábitat. Cercas definen cultivos o áreas de pastoreo usando alambre de púas y postes de madera, pero las cercas vivas reemplazan los postes de madera con árboles, creando corredores que animales pueden usar para moverse a través del paisaje fragmentado. Nosotros capturamos 279 murciélagos de 17 especies a lo largo de 27 sitios pareados de cercas tradicionales y cercas vivas conectando bosque seco tropical mesoamericano en el sudeste de Nicaragua. Riqueza y capturas de murciélagos fueron dos y cuatro veces mas altas en cercas vivas. Sin embargo, diferencias en proporciones de sexo, riqueza y composición de las capturas indican que las cercas vivas no proveen los mismos beneficios de conectividad para todas las especies.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153733/1/btp12751_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/153733/2/btp12751.pd

Snakebite: An Exploratory Cost-Effectiveness Analysis of Adjunct Treatment Strategies.

The cost-effectiveness of the standard of care for snakebite treatment, antivenom, and supportive care has been established in various settings. In this study, based on data from South Indian private health-care providers, we address an additional question: "For what cost and effectiveness values would adding adjunct-based treatment strategies to the standard of care for venomous snakebites be cost-effective?" We modeled the cost and performance of potential interventions (e.g., pharmacologic or preventive) used adjunctively with antivenom and supportive care for the treatment of snakebite. Because these potential interventions are theoretical, we used a threshold cost-effectiveness approach to explore this forward-looking concept. We examined economic parameters at which these interventions could be cost-effective or even cost saving. A threshold analysis was used to examine the addition of new interventions to the standard of care. Incremental cost-effectiveness ratios were used to compare treatment strategies. One-way, scenario, and probabilistic sensitivity analyses were conducted to analyze parameter uncertainty and define cost and effectiveness thresholds. Our results suggest that even a 3% reduction in severe cases due to an adjunct strategy is likely to reduce the cost of overall treatment and have the greatest impact on cost-effectiveness. In this model, for example, an investment of $10 of intervention that reduces the incidence of severe cases by 3$75 per individual. These findings illustrate the striking degree to which an adjunct intervention could improve patient outcomes and be cost-effective or even cost saving

Nut production in Bertholletia excelsa across a logged forest mosaic: implications for multiple forest use

Although many examples of multiple-use forest management may be found in tropical smallholder systems, few studies provide empirical support for the integration of selective timber harvesting with non-timber forest product (NTFP) extraction. Brazil nut (Bertholletia excelsa, Lecythidaceae) is one of the world’s most economically-important NTFP species extracted almost entirely from natural forests across the Amazon Basin. An obligate out-crosser, Brazil nut flowers are pollinated by large-bodied bees, a process resulting in a hard round fruit that takes up to 14 months to mature. As many smallholders turn to the financial security provided by timber, Brazil nut fruits are increasingly being harvested in logged forests. We tested the influence of tree and stand-level covariates (distance to nearest cut stump and local logging intensity) on total nut production at the individual tree level in five recently logged Brazil nut concessions covering about 4000 ha of forest in Madre de Dios, Peru. Our field team accompanied Brazil nut harvesters during the traditional harvest period (January-April 2012 and January-April 2013) in order to collect data on fruit production. Three hundred and ninety-nine (approximately 80%) of the 499 trees included in this study were at least 100 m from the nearest cut stump, suggesting that concessionaires avoid logging near adult Brazil nut trees. Yet even for those trees on the edge of logging gaps, distance to nearest cut stump and local logging intensity did not have a statistically significant influence on Brazil nut production at the applied logging intensities (typically 1–2 timber trees removed per ha). In one concession where at least 4 trees ha-1 were removed, however, the logging intensity covariate resulted in a marginally significant (0.09) P value, highlighting a potential risk for a drop in nut production at higher intensities. While we do not suggest that logging activities should be completely avoided in Brazil nut rich forests, when a buffer zone cannot be observed, low logging intensities should be implemented. The sustainability of this integrated management system will ultimately depend on a complex series of socioeconomic and ecological interactions. Yet we submit that our study provides an important initial step in understanding the compatibility of timber harvesting with a high value NTFP, potentially allowing for diversification of forest use strategies in Amazonian Perù

Construcción modular de habitajes turísticos en madera, para zonas de clima tropical

En les pàgines posteriors d'aquest text s'explora l'aplicació de construccions modulars en fusta en zones de clima tropical. L'objectiu de l'estudi és investigar la viabilitat i avantatges d'utilitzar estructures modulars de fusta com una solució sostenible i adaptable per a la indústria de la construcció en regions tropicals. La investigació es centra a analitzar els aspectes tècnics i mediambientals de les construccions modulars en fusta, incloent propietats d'aïllament tèrmic, resistència a les condicions climàtiques i tractaments previs per a la fusta. L'estudi també avalua la viabilitat i adequació cultural de les construccions modulars de fusta en àrees tropicals. La metodologia de recerca inclou una exhaustiva revisió de literatura i estudis de casos per avaluar els possibles beneficis i limitacions de les construccions modulars en fusta en climes tropicals. Els troballes d'aquest estudi contribueixen al cos de coneixement en pràctiques de construcció sostenible i proporcionen informació valuosa per a arquitectes, enginyers i responsables de polítiques involucrats en el desenvolupament de regions tropicals. Paraules clau: Habitatges, sostenible, habitatges prefabricades, modular, turisme.En la páginas posteriores de este texto se explora la aplicación de construcciones modulares en madera en zonas de clima tropical. El objetivo del estudio es investigar la viabilidad y ventajas de utilizar estructuras modulares de madera como una solución sostenible y adaptable para la industria de la construcción en regiones tropicales. La investigación se enfoca en analizar los aspectos técnicos y medioambientales de las construcciones modulares en madera, incluyendo propiedades de aislamiento térmico , resistencia a las condiciones climáticas y tratamientos previos para la madera. El estudio también evalúa la viabilidad y adecuación cultural de las construcciones modulares de madera en áreas tropicales. La metodología de investigación incluye una exhaustiva revisión de literatura y estudios de casos para evaluar los posibles beneficios y limitaciones de las construcciones modulares en madera en climas tropicales. Los hallazgos de este estudio contribuyen al cuerpo de conocimiento en prácticas de construcción sostenible y brindan información valiosa para arquitectos, ingenieros y responsables de políticas involucrados en el desarrollo de regiones tropicales. Palabras clave: Habitajes, sostenibles, viviendas prefabricadas, modular, turismo.In the following pages of this text, the application of modular wooden constructions in tropical climate zones is explored. The aim of the study is to investigate the feasibility and advantages of using modular wooden structures as a sustainable and adaptable solution for the construction industry in tropical regions. The research focuses on analyzing the technical and environmental aspects of modular wooden constructions, including thermal insulation properties, resistance to climatic conditions, and pre-treatments for wood. The study also evaluates the viability and cultural suitability of modular wooden constructions in tropical areas. The research methodology includes a comprehensive literature review and case studies to assess the potential benefits and limitations of modular wooden constructions in tropical climates. The findings of this study contribute to the body of knowledge in sustainable construction practices and provide valuable insights for architects, engineers, and policymakers involved in the development of tropical regions. Keywords: Dwellings, sustainable, prefabricated houses, modular, tourism