Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

The present study aims to characterize the floristic composition, structure, and diversity of the urban tree population in the canton of Puerto López, Manabí, Ecuador. To achieve this, a forest census was conducted in 10 public spaces, including 7 parks and 3 green areas. A total of 16 tree species were recorded, distributed across 11 botanical families, with 279 individuals. The Fabaceae family was the most representative in the study area. Regarding the horizontal structure of the species, a normal distribution was observed in relation to the diameter of the trees, with greater abundance in the diameter range of 10 to 30 cm. The vertical structure of the trees showed that 61 % of the trees had heights ranging from 3 to 9 m. Additionally, the area in square meters of the green spaces was determined to calculate the urban green index, obtaining a value of 5,70 m²/capita, which is below the WHO recommendation of 9 m²/capita. Various ecological value indices were also applied to assess the biodiversity of the tree population. The non-native index revealed that 75 % of the green areas contain non-native species. Other indices, such as Shannon-Wiener (2,07), Pielou (0,52), Simpson (0,62), Berger-Parker (0,59), Margalef (2,66), and Jaccard (19 %), allowed for a comprehensive evaluation of diversity, equitability, and similarity among species in the urban tree population of the studied area. These results contribute to the development of future management and conservation strategies for urban greenery.

The study investigated the impact of age (E) and variety (V) on several plant characteristics, including plant height (AP) in centimeters, forage biomass (FB) in kilograms of dry matter per hectare, stem weight (PT), leaf number (LH), leaf area (LA), leaf-stem ratio (LSR), and the chemical composition of three grass species: Axonopus micay, Axonopus scoparius, and Melinis minutiflora. The grasses were harvested at five different stages of maturity (30, 45, 60, 75, and 90 days). A randomized complete block design with a factorial arrangement (3 x 5) was employed, resulting in a total of 75 plots. Notably, the purple Gramalote grass (Axonopus scoparius) outperformed the other varieties in terms of AP, PT, LH, AH, PH, and H:T ratio, with specific measurements of 168,46 cm, 97,24 g, 64,02 cm, 3,72 cm, 32,39 g, and 0,37, respectively. Additionally, at 90 days, the highest values were observed for AP (138,83 cm), PT (58,96 g), LH (41,74 cm), AH (2,94 cm), PH (15,69 g), and biomass (1 682,5 kg MS ha-1). Furthermore, the dry matter content (%) of the purple Gramalote grass (33,16) exceeded that of the Gordura grass (32,38) and Micay grass (21,97). In terms of ash and crude protein content, the Gramalote morado variety exhibited higher values (9,65 and 9,09 respectively). 

Nutrient uptake by black pepper (Piper nigrum) is crucial for estimating its nutritional demand and designing efficient fertilization plans. This study evaluated nutrient absorption in different plant organs during the initial production stage (1,5 years) in a crop located in Valle Hermoso parish, Santo Domingo de los Tsáchilas, Ecuador. A completely randomized design was used, applying the Di Rienzo, Guzman and Casanoves test for mean comparisons (a = 0,05). Treatments included plant organs, macronutrients, and micronutrients, with three replicates per treatment. The main results revealed that leaves had the highest contents of nitrogen, potassium, and calcium calcium (2,86 ± 0,18 to 3,14 ± 0,26 dag kg-1), while roots accumulated higher amounts of boron, zinc, copper, and iron. Similarly, leaves absorbed the largest quantities of nitrogen, calcium, and sulfur (1,00 ± 0,32 to 40,5 ± 3,1 kg ha-1), as well as boron, zinc, and manganese (32,6 ± 3,9 to 217,1 ± 21,5 g ha-1). Macronutrient uptake followed the order nitrogen = potassium = calcium > magnesium > phosphorus = sulfur, while for micronutrients, it was iron > manganese > zinc > boron > copper. These findings are essential for designing fertilization plans that optimize nutrient availability and uptake in black pepper crops during their initial production stage.

Ensuring the provision of high-quality and risk-free food to the public health necessitates the implementation of robust food production systems encompassing the entire chain from producer to consumer. The availability of safe and wholesome food is an essential consumer demand and a societal necessity. In Ecuador, currently, there are no legal provisions regulating the application of the Hazard Analysis and Critical Control Points (HACCP) system for managing the health risks associated with products such as margarines. The present study was undertaken with the objective of establishing the theoretical and methodological foundations for implementing the HACCP system in the production of sunflower margarine. To achieve this, the following activities were carried out: development of a flowchart for the process of obtaining and storing raw materials, identification of Critical Control Points (CCPs), establishment of critical limits for each identified CCP, and proposals for corrective actions for potential deviations from these critical limits. The study confirms the feasibility of the HACCP system for the production of sunflower margarine, and critical control points have been identified in the production chain. However, the quality of the raw materials could be compromised, posing a potential risk to consumer health.

This study aims to explain the temporal variation of PM10 particles in Quito's air quality, estimate future pollution risks, and minimize adverse health effects through the implementation of preventive measures. The research adopts a quantitative approach, focusing on data from the Quito Metropolitan Atmospheric Monitoring Network (REMMAQ) to predict PM10 pollution. The results indicate that the average particulate matter concentrations at each station for a year are acceptable based on homoscedasticity, stationarity, and normality models. The most suitable station is Guamaní, where particulate matter concentrations reach up to 38.8%. According to forecasts, air quality is considered good when it falls within the 0-50 range, where the health effects are acceptable. Guamaní consistently presents acceptable values in the range, The selected ARIMA (2, 1, 5) model, with an acceptable and appropriate fit, provides a robust alternative for managing air quality through PM10 particles using time series analysis. This study provides valuable information on air quality in Quito and the potential to address air pollution.

Minquartia guianensis and Hyeronima alchorneoides are two valuable woody species in the Costa Rican tropical wet forest. Little is known about the genetic diversity of these species. Using 20 random amplified polymorphic DNA (RAPD) primers, we estimated the levels of diversity and variance within and among three distinct areas for each species within La Selva Biological Station. Genetic diversity was calculated using classical and Bayesian estimators, and their values were similar. The results indicated high levels of variance within patches (78% in M. guianensis and 87% in H. alchorneoides). We also estimated the genetic distance, and the dendrograms indicated a lack of differentiation between the patches for both species. Our data are consistent with studies of genetic variation in other tropical trees.

This research problematizes the field of biomaterials, examining their production rationale in the context of climate and ecological crises. The initial section outlines eleven fundamental categories to understand the production and research of biomaterials in Costa Rica, juxtaposed with theoretical discussions of global scope about how these categories are understood and conceptualized. The second part proposes a conceptual framework that organizes these approaches and redefines four key concepts. The research takes an interdisciplinary approach, integrating methods and subjects from the biological sciences, materials engineering, design, and art, along with tools from the social sciences and philosophy. It is concluded that conceptual distinctions extend beyond the scientific realm; biomaterial productions also imply political, socio-environmental, and ecological dimensions that must be differentiated through new concepts. Likewise, it is argued that inter/transdisciplinary research and the application of new biomaterials must constantly explore the concepts they engage with and critically assess the inherent production logic and its impact on the global environmental crisis and local ecosystems.

Shallow marine ecosystems with extensive communities of submerged aquatic vegetation, including seagrasses and macroalgae, are found along the northern coast of the Yucatán Peninsula. This study describes the geomorphological complexity of the nearshore seafloor in Yucatán, Mexico, and its association with submerged aquatic vegetation communities, constituting the first effort of its kind in this region. This work is relevant because ecological interactions between the seafloor and its inhabitants define the spatial structure of ecosystems, as well as ecological processes, many of which provide benefits to human society. The objectives of this study were to: (1) spatially delineate discrete geomorphological units (structures and zones) based on their depth, slope, and aspect; (2) describe the relative abundance of major groups of submerged aquatic vegetation (seagrasses, green algae, red algae, brown algae, and algal turf); and (3) assess the association between geomorphology and the presence of the vegetation groups under study. This information establishes a baseline for biological, ecological, and oceanographic analyses of the coastal marine ecosystems in southeastern Mexico. In addition, the results of this study are crucial for decision-making related to coastal development, adaptive management, and environmental conservation monitoring, and provide a foundation for functional ecosystem assessment studies.

Rocky-coral ecosystems host highly heterogeneous habitats and functionally diverse fish communities. Within these systems, coral microhabitats play a pivotal role by offering a subset of the available resources to cryptofauna, particularly cryptobenthic reef fishes (CRF), which are notable for their abundance and diversity. This group of fishes, with adult lengths of less than 5 cm, shows highly specialized visual and behavioral camouflage, which often leads to their underrepresentation in studies. Due to the scarcity of research and the significant taxonomic complexity of CRF, this study investigated the association between CRF and the massive coral Porites panamensis in Bahía de los Ángeles, Gulf of California, and rocky substrate. We hypothesized that CRF densities would be higher in coral microhabitats because of their superior three-dimensional complexity. Two extractive sampling efforts were conducted in March and October 2022 (n = 16). A total of 238 individuals were collected, representing 14 species from 5 fish families. Five species accounted for 76.62% of the total abundance, with the families Gobiidae, Tripterygiidae, and Chaenopsidae being the most represented. The average density of CRF in P. panamensis microhabitats was twice that observed in rocky microhabitats (W = 46.5, P = 0.036). Moreover, CRF assemblage structure and composition differed significantly between microhabitats (Pseudo-F = 4.41, P = 0.004). These findings highlight the critical role of P. panamensis as a microhabitat and its influence on the benthic organization of CRF. Given the ongoing degradation of coral cover and the decline in structural habitat complexity, these results are essential to understand long-term shifts in cryptofaunal communities.

Coral bleaching is caused mainly by heat stress, as the rise in temperature generates increasingly frequent and intense heat waves. In addition to the increase in temperature, sediment contributions in the Veracruz Reef System (VRS) could increase stress and, with it, the susceptibility of corals to bleaching. This work evaluated 2 reefs of the VRS on 2 time scales: (1) in the short term (2022 to 2023), using the bleaching response index (BRI) to assess the recovery of 104 colonies of scleractinian corals on a scale of 1 to 6 and (2) in the medium term (2008 to 2021), through the coral index (CI) to assess the health of the coral community on a scale of 1 to 5. High values reflect better condition of the corals. In addition, the number of bleached colonies was related to degree heating week (DHW) values and sedimentation rates in both periods. We found that the degrees of accumulated heat were the main cause of bleaching events, whereas sediments did not have a direct influence. In 2022, the prevalence of bleaching was 17% with values of 5 DHW, with Montastraea cavernosa, Siderastrea siderea, Siderastrea stellata, and Colpophyllia natans being the most affected species. However, most exhibited an increase in pigmentation within the first 5 months, with BRI values of 5 and 6. During the period of 2008 to 2021, the health of coral communities was classified as good, with CI values of 3.8 and 3.6. The results illustrate that scleractinian corals have been resilient to bleaching events under VRS conditions, highlighting the need to continue with in situ studies of the susceptible species in this study.