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The sustainability of ecotourism initiatives represents a major challenge. The aim of this study is to enhance our understanding of how community participation in ecotourism management can contribute toward achieving more sustainable results by identifying key factors that make it possible to potentiate a broader range of economic, social and environmental objectives. Based on the theory of collaborative planning and the strategic focus of community tourism, our work adopted a mixed approach to compare and explain the differences between two local cooperatives on the coast of the state of Nayarit, Mexico. The results reveal statistically‑significant differences between the benefits obtained through ecotourism and identify the factors that foment active community participation by local residents that, in turn, generates positive correlations with those benefits. Findings were supported by qualitative interviews with external informants. Our conclusion is that the level of benefits obtained can be reasonably explained by a set of six key factors

In order to meet consumer needs, the livestock industry is increasingly seeking natural feed additives with the ability to improve the efficiency of nutrient utilization, alternatives to antibiotics, and mitigate methane emissions in ruminants. Chitosan (CHI) is a polysaccharide with antimicrobial capability against protozoa and Gram-positive and -negative bacteria, fungi, and yeasts while naringin (NA) is a flavonoid with antimicrobial and antioxidant properties. First, an in vitro gas production experiment was performed adding 0, 1.5, 3.0 g/kg of CHI and NA under a completely randomized design. The substrate containing forage and concentrate in a 70:30 ratio on a dry matter (DM) basis. Compounds increased the concentration of propionic acid, and a significant reduction in methane production was observed with the inclusion of CHI at 1.5 g/kg in in vitro experiments (p < 0.001). In a dry matter rumen degradability study for 96 h, there were no differences in potential and effective degradability. In the in vivo study, six crossbred heifers fitted with rumen cannulas were assigned to a 6 × 6 Latin square design according to the following treatments: control (CTL), no additive; chitosan (CHI1, 1.5 g/kg DMI); (CHI2, 3.0 g/kg DMI); naringin (NA1, 1.5 g/kg DMI); (NA2, 3.0 g/kg DMI) and a mixture of CHI and NA (1.5 + 1.5 g/kg DMI) given directly through the rumen cannula. Additives did not affect rumen fermentation (p > 0.05), DM intake and digestibility of (p > 0.05), and enteric methane emissions (p > 0.05). CHI at a concentration of 1.5 g/kg DM in in vitro experiments had a positive effect on fermentation pattern increasing propionate and reduced methane production. In contrast, in the in vivo studies, there was not a positive effect on rumen fermentation, nor in enteric methane production in crossbred heifers fed a basal ration of tropical grass.

Life Cycle Assessment (LCA) is considered an innovative tool to analyze environmental impacts to make decisions aimed at improving the environmental performance of building materials and construction processes throughout different life cycle stages, including design, construction, use, operation, and end-of-life (EOL). Therefore, during the last two decades, interest in applying this tool in the construction field has increased, and the number of articles and studies has risen exponentially. However, there is a lack of consolidated studies that provide insights into the implementation of LCA on construction and demolition waste (C&DW). To fill this research gap, this study presents a literature review analysis to consolidate the most relevant topics and issues in the research field of C&DW materials and how LCA has been implemented during the last two decades. A systematic literature search was performed following the PRISMA method: analysis of selected works is based on bibliometric and content-based approaches. As a result, the study characterized 150 selected works in terms of the evolution of articles per year, geographical distribution, most relevant research centers, and featured sources. In addition, this study highlights research gaps in terms of methodological and design tools to improve LCA analysis, indicators, and connection to new trending concepts, such as circular economy and industry 4.0.

Wave energy, a form of renewable energy, is derived from the movement of sea waves. Wave energy generation devices are technologies designed to harness this resource and convert it into electricity. These devices are classified based on their location, size, wave direction, and operating principle. This work presents the design of an oscillating device for harnessing wave energy. For this purpose, computational fluid dynamics and response surface methodology were employed to evaluate the influence of the percentage of the blade height submerged below the water surface (X1) and the distance from the device to the breakwater in terms of the percentage of the wave length (X2). The response variable studied was the hydrodynamic efficiency (η) of the device. Transient fluid dynamic simulations were carried out using Ansys Fluent software 2023 R1, with input conditions based on a wave spectrum characteristic of the Colombian Pacific Ocean. Analysis of variance determined that both factors and their interaction have significant effects on the response variable. Using the obtained regression model, the optimal point of the system was determined. Numerical results showed that the maximum η of the system was achieved when the device was submerged at 75% of its height and was positioned 10% of the wave length away from the vertical breakwater. Under this configuration, η was 64.8%. Experimental validations of the optimal configuration were conducted in a wave channel, resulting in a η of 45%. The difference in efficiencies can be attributed to mechanical losses in the power take-off system, which were not considered during the numerical simulations.

Climate change and fragmentation are major threats to world forests. Understanding how functional traits related to drought tolerance change across small-scale, pronounced moisture gradients in fragmented forests is important to predict species' responses to these threats. In the case of Aextoxicon punctatum, a dominant canopy tree in fog-dependent rain forest patches in semiarid Chile, we explored how the magnitude, variability and correlation patterns of leaf and xylem vessel traits and hydraulic conductivity varied across soil moisture (SM) gradients established within and among forest patches of different size, which are associated with differences in tree establishment and mortality patterns. Leaf traits varied across soil-moisture gradients produced by fog interception. Trees growing at drier leeward edges showed higher leaf mass per area, trichome and stomatal density than trees from the wetter core and windward zones. In contrast, xylem vessel traits (vessels diameter and density) did not vary producing loss of hydraulic conductivity at drier leeward edges. We also detected higher levels of phenotypic integration and variability at leeward edges. The ability of A. punctatum to modify leaf traits in response to differences in SM availability established over short distances (<500 m) facilitates its persistence in contrasting microhabitats within forest patches. However, xylem anatomy showed limited plasticity, which increases cavitation risk at leeward edges. Greater patch fragmentation, together with fluctuations in irradiance and SM in small patches, could result in higher risk of drought-related tree mortality, with profound impacts on hydrological balances at the ecosystem scale.

The effects of environmental degradation on human health and the life of plants and animals have motivated politicians, researchers, and organizations such as the OECD to address this issue. The text adheres to conventional academic structure, using clear and objective language with precise word choice. The language is formal and free from grammatical errors, spelling mistakes, and punctuation errors. The text maintains a balanced perspective and avoids biased language. No changes in content were made. Abstract: This study examines the research trends on the relationship between economic growth and environmental degradation. The study employed a quantitative, exploratory methodology and conducted a bibliometric analysis of articles registered in the Scopus and Web of Science databases from 1972 to 2022. The search equations were structured based on the parameters of the international declaration PRISMA. The study considered bibliometric indicators of quality, quantity, and structure. VOSviewer was used to construct and visually present bibliometric networks on the structure and dynamics of the subject under study. The data indicates a noteworthy rise in the quantity of publications and authors examining the applicability of the Kuznets curve to ecological footprint and carbon emissions indicators, which are considered the most significant factors. This suggests an inverted U-shaped correlation between economic growth and environmental degradation. Notably, it underscores the adverse contribution of inadequate natural resource consumption, especially non-renewable energy, to environmental degradation. Overall, these implications underscore the urgency of concerted efforts to address this critical issue.

Cleaner production has been used for several years in Latin America to minimize waste generation while reducing material and energy consumption. Despite those environmental benefits, its implementation may sometimes lead to changes in products or processes whose environmental performance can yield either positive or negative outputs when examined within a broader context, meaning it is necessary to complement cleaner production with other environmental tools that can provide environmental assessments. This paper presents a combination of cleaner production with life cycle assessment (LCA) applied within the wood industry in a case study in Salvador, a state of Bahia (Brazil), regarding the production of two models of wooden chairs. The study selected life cycle assessment as a scientific tool to quantify the environmental impacts of the models having ILCD 2011 midpoint and cumulative energy demand methods. The results confirmed the presence of environmental tradeoffs among the models that were not considered during the cleaner production program implemented. This paper also includes a proposal of a flowchart to guide the implementation of cleaner production when deciding to implement changes in material, energy source, processes, final destination, or lifespan of the product evaluated, identifying the stages where environmental assessment like life cycle assessment may be required to address tradeoffs.