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Copyright of Environmental & Social Management Journal / Revista de Gestão Social e Ambiental is the property of Environmental & Social Management Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nonlinear regression modeling was used to study the nursery production of the oyster Crassostrea virginica in the Celestún (CL) and Rio Lagartos (RL) lagoons in Yucatán, Mexico. Relationships between production parameters and environmental variables were also established. Spat (2.40 ± 0.20 mm) was obtained from a hatchery and reared in Nestier- type trays using an off-bottom system. Oyster cultivation took place from May 2021 to September 2021 and ended after 122--126 days when oysters reached 30.00 mm. There were no significant differences in final height (CL: 30.80 ± 0.42 mm; RL: 31.80 ± 0.65 mm; P = 0.18) and growth rate (CL: 0.23 ± 0.02 mm·d-1; RL: 0.23 ± 0.01 mm·d-1; P = 0.98). Final survival was 71.45% in CL and 99.40% in RL. Nonlinear regression curves were statistically satisfactory for analyzing growth and survival. Salinity (CL: 15.23 ppt; RL: 35.02 ppt), temperature (CL: 29.64 °C; RL: 31.02 °C), dissolved oxygen (CL: 4.50 mg· L-1; RL: 5.04 mg· L-1), pH (CL: 8.10; RL: 8.34), chlorophyll a (Chl a) (CL: 3.23 mg·m--3; RL: 6.85 mg·m--3), and total dissolved solids (CL: 16,101 mg·L-1; RL: 34,838 mg·L-1) were significantly higher in RL (P < 0.05). Except for Chl a, the environmental variables were more stable in RL than in CL (P < 0.05). In RL, the growth rate was positively related to salinity and pH. In CL, the growth rate slowed when salinity decreased, and the mortality rate diminished when salinity, dissolved oxygen, and total dissolved solids increased and pH decreased. Salinity was mainly responsible for the observed differences in production between lagoons. Even when temperature and salinity were high in RL, acceptable growth rate and survival were observed, possibly due to stable rearing conditions. [ABSTRACT FROM AUTHOR]

The study of the functioning of the high Andean ecosystems is of great importance since any change will influence the entire basin. However, knowledge of these environments is still limited. Therefore, we sought to determine the effect of seasonality on the macrobenthos assemblage of a high Andean River and to determine the limnological, geomorphological, and hydrologicalhydraulic variables that most influence it. In the El Salto River, located 4,500 meters above sea level, in high Andean environments in southern Peru, macrobenthos was collected in 2020 in 11 hydro morphological units, recording limnological variables (dissolved oxygen, saturation percentage, conductivity, TSD, temperature, pH, turbidity and SS), geomorphological (granulometry) and hydrological-hydraulic (flow, velocity, depth, channel width) in dry and wet seasons. The principal component analysis (PCA) of the physicochemical variables showed that the flow rate, conductivity, pH, and total dissolved solids explained the greatest variability of the data (70 %). The predominance of boulders and silt was found. The number of species and density were higher in the dry season than in the wet season. However, the diversity, richness, and equity were higher in the wet season. The ordination analysis (nMDS, stress=0.09) showed a different structure of the macrobenthic assemblage between both seasons. It is concluded that seasonality, given by various factors, mainly flow rate and flow velocity, determine variations in the macrobenthos assemblage, confirming the drastic changes to which these high Andean ecosystems with extreme climates are subjected. [ABSTRACT FROM AUTHOR]

Se determinó la variación espacio-temporal de la biomasa de los grupos morfo-funcionales de macroalgas y su relación con las variables ambientales: temperatura, salinidad, oxígeno disuelto y precipitaciones en dos localidades (laguna y playa) de pastizales al Norte de Ciego de Ávila desde marzo de 2010 a febrero de 2011. Las colectas se realizaron utilizando marco cuadrado de 25 cm de lado y se tomaron 15 unidades de muestreo en cada sitio. Se determinaron cinco grupos morfo-funcionales: foliosas y globosas, coriáceas, filamentosas, corticadas y calcáreas articuladas, presentando variaciones espacio-temporales los dos últimos. La laguna tuvo menor diversidad algal (13 géneros) y mayor biomasa total determinado por el aporte de las calcáreas articuladas, mientras que la playa fue más diversa (26 géneros) y menos productiva. Los picos máximos se presentaron en verano debido al enriquecimiento producto del arrastre por las lluvias y los mínimos enprimavera. Las variaciones espaciales pudieron estar dadas por las diferencias del régimen hidrodinámico, los nutrientes y el sustrato. La variación temporal de la biomasa de las corticadas y filamentosas mostró correlación con valores elevados de salinidad y oxígeno disuelto y las calcáreas articuladas y coriáceas lo fueron para valores elevados de temperatura y precipitaciones.

Introduction: The maintenance of the coral communities depends directly on the capacity of the individuals to grow as a whole colony. Since growth shapes the basis of the physical structure of the reef, determining the growth rate of builder coral-species and their response to environmental variations will allow us to identify their particular potential to implement more effective restoration strategies. Objective: To determine the growth rate of the reef-building coral Pocillopora throughout the Mexican Central Pacific (PCM) and its relationship with fluctuations in environmental conditions. Methods: From August 2019 - October 2020, a total of 153 branched coral fragments of the genus Pocillopora were monitored and transplanted as part of the restoration program in different PCM locations: Islas Marietas National Park and in the Caleta de Cuastecomates. Coral growth (cm·year-1) and survival rate (%), was calculated and correlated with temperature, PAR and Kd490 for each locality. Results: The results show similar patterns in the parameters examined among the coral fragments were found for all sites, with a survival range of 61.6 - 68 %, whose mortality was mainly related to hurricanes and storms that affected the region. However, growth rate range from 2.0 - 8.0 cm·year-1, with no significant differences between locations. Also, no differences in environmental conditions between locations were recorded. Conclusions: The branching corals of the genus Pocillopora present a similar growth rate in insular and coastal sites of the PCM, so it could be expected that the implementation of a restoration program throughout this region of the Mexican Pacific would be potentially successful, since local environmental conditions are not limiting factors. [ABSTRACT FROM AUTHOR]

El cambio climático es un calentamiento global, consecuencia de la producción de gases de efecto invernadero y produce un exceso de calor en las capas inferiores de la atmosfera. Estos cambios en el clima pueden ocasionar alteraciones en los ciclos de vida de varias especies como los mosquitos de Aedes aegypti, considerado un vector importante de transmisión de enfermedades. El objetivo de este trabajo fue realizar una búsqueda sistemática de artículos referentes a la posible relación entre el cambio climático y la aparición del riesgo de transmisión de la fiebre de dengue por Ae. aegypti y su adaptación a las condiciones ambientales locales. Para ello se realizó una búsqueda sistemática en tres bases de datos diferentes: Scopus, Google Scholar y CICCO (Springer link, Scielo, DOAJ) Se tuvieron en cuenta 3 preguntas clave de los cuales derivaron las palabras clave de búsqueda y sentencias lógicas. Se obtuvo un flujograma donde se aprecia como el número de búsqueda se redujo de 651 a 27 artículos científicos. Factores como la urbanización, la falta de servicios básico y variaciones en la temperatura, humedad ambiental y precipitaciones pueden aumentar el riesgo de epidemias a nivel global ya que varios insectos y en especial el Ae. Aegypti cambian para adaptarse a las condiciones ambientales locales.

La protección al medio ambiente representa un elemento de vital importancia para garantizar la subsistencia de la especie humana. Diversas normas han sido implementadas para asegurar su cuidado. Sin embargo, cuantificar el impacto del cumplimiento de las variables ambientales representa una actividad poco abordada por la ciencia. La presente investigación tiene como objetivo desarrollar un método para medir la implementación de las variables ambientales. El método basa su funcionamiento mediante la modelación de las relaciones causales a partir del mapa cognitivo difuso. La propuesta se implementa en la comunidad de Jipijapa con el objetivo de intencional el cumplimiento de las variables con mayor deficiencia.

En el entorno en que vivimos, se identifican un conjunto de variables ambientales que poseen determinado comportamiento. Evaluar y clasificar el comportamiento de las variables en su entorno, representa un problema de toma de decisiones que determina hacia donde centrar los esfuerzo en el trabajo ambiental. La presente investigación propone como objetivo desarrollar un método para la clasificación de variables ambientales. El método basa su funcionamiento mediante un sistema de actividades que en su integración marcan la inferencia. Como resultado de la implementación del método se identifica el comportamiento de las variables ambientales en un escenario donde se recomienda trabajar en función de corregir el comportamiento de los indicadores más deprimidos.

Ecosystem dynamics is based on successional processes that occur after anthropic and natural disturbances. The succession of native woody plant species was studied under a plantation of Eucalyptus globulus in Loja, Ecuador; with the objective of determining the floristic composition and monitoring natural regeneration. Five permanent plots of 20 m x 20 m were established to investigate latizales, five subplots of 5 m x 5 m were nested for saplings and five subplots of 1 m x 1 m for seedlings. Height and basal diameter were measured at the beginning of the experiment and at 12 months. Floristic composition and structural parameters were determined at the first sampling time; with the data from the second measurement, survival and growth were evaluated. The influence of the environmental variables: soil depth, slope and luminosity on the floristic diversity and abundance of natural regeneration were analyzed. Twenty-eight species within 24 genera and 21 families were recorded. The abundant species with the highest IVI are: Solanum aphyodendron (seedlings), Miconia obscura (sapling) and Viburnum triphyllum (latizal). Seedlings have a higher survival rate (100 %) and saplings have a lower survival rate (88.55 %). Viburnum triphyllum (seedlings), Verbesina arborea (saplings) and Inga acreana (grassland) showed the highest growth in height. Basal diameter is dominated by Solanum aphyodendron (seedlings), Alnus acuminata (saplins) and Critoniopsis pycnantha (latizal). The floristic diversity present in the latizales correlates with the environmental variables, in the seedlings and saplings there is no significant relationship.

Copyright of Acta Universitaria is the property of Universidad de Guanajuato/Acta Universitaria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Salud Bosque is the property of Universidad El Bosque and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The reproductive strategy of a species must be adjusted to variations in environmental conditions to guarantee population balance. Hydrological fluctuations in Amazonian streams of terra firme (non-flooded) are controlled primarily by local rainfall. Fish assemblages are composed predominantly of species of small size. We investigated the reproductive strategy of the cryptic catfish Helogenes marmoratus and assessed the influence of environmental variables (e.g., rainfall, conductivity, habitat descriptors) on its reproductive activity in a catchment of the Guamá River in the eastern Brazilian Amazon. Through monthly collections between March 2019 and March 2020, we identified an extended reproductive period between July 2019 and March 2020. Males mature at smaller sizes than females (♂ = 27.41 mm; ♀ = 31.36 mm). We confirmed batch spawning, low fecundity (59.55 ± 22.76 stage IV oocytes), and large oocytes (1.24 ± 0.15 mm). Our results indicated that H. marmoratus strategy occupies an intermediate place between opportunistic and equilibrium gradient. Multiple regressions showed that thalweg depth, electrical conductivity, leaf litter, and rainfall are important drivers of reproductive activity of females of H. marmoratus, explaining 32% of the variation of the GSI. Our study provides evidence of differentiated reproductive response between the sexes to environmental variables. [ABSTRACT FROM AUTHOR]

Introduction: Coral reefs are negatively affected by different anthropogenic and environmental causes in the Gulf of Papagayo, Costa Rican Pacific coast. Objective: The health status of the Playa Blanca coral reef was evaluated. Methods: Between August 2010 and September 2011, the percentage of live coral cover (LCC) per species and of the macroalgae Caulerpa sertularoides was determined in four sectors and at three depths of the coral reef; the annual growth of Pocillopora damicornis and P. elegans was measured and related to temperature, nutrients, wind, sun irradiation and rain. Results: 14 species of corals were found, two of them, Fungia curvata and Leptoseris papyracea, only as skeletons. The area with the highest LCC was offshore in the middle zone of Playa Blanca. The species with the highest coverage in all depth ranges was P. damicornis, followed by P. elegans. The LCC decreased from 29% in September 2010 to 1% in October 2010 due to a mass coral mortality caused by harmful algal blooms. The growth rate of P. damicornis (26.0 ± 8.9 mm year-1) and P. elegans (27.9 ± 4.5 mm year-1) did not show significant differences between depths or location in the reef. Conclusions: The exuberant Playa Blanca coral reef experienced a sudden drop in LCC similar to those described by Glynn et al. (1983). This suggests that cycles of mortality and natural recovery of coral reefs occur, although anthropogenic pressures reduce the resilience capacity of the reefs. Spatial planning, both on land and in the sea, is vital for adequate human development, in which the increase in the resilience of coral ecosystems is incorporated into the analysis. [ABSTRACT FROM AUTHOR]

Introduction: Numbers of alien plant species are rising around the globe, but not all of them become invasive. Whereas introductions have been documented for several decades in some regions of the world, knowledge on alien species in Western Mexico is limited. Here, we study roadside vegetation along an elevational gradient, which includes a protected area. Objective: We analysed the floristic composition of herbaceous alien species, their distribution patterns, and their relationship with various environmental factors. A relative importance value index (IVI) identified the most important and, therefore, probably invasive taxa. Methods: During 2017 and 2018, roadside vegetation was documented with 4-6 transects every 300 altitudinal meters, from 0 to 2 100 m, for a total of 37 transects. Each transect consisted of five 1 m² plots. All herbaceous species were registered and alien taxa identified. A cluster analysis distinguished grouping of species based on elevation. The potentially invasive species were identified by their IVI, based on the sum of relative frequency and density values. The influence of environmental variables was analysed with a canonical correspondence analysis. Results: Most alien species were grasses; other families were represented by one or two species. The species were grouped into three main clusters. The first group included rare species, the second consisted of species restricted to higher altitudes, and the third group were tropical taxa with a distribution from sea level to medium altitudes. The most important potentially invasive species were: Urochloa maxima, Melinis repens, Eragrostis ciliaris and Cynodon dactylon, all African grasses introduced for grazing. The IVI of the species was related to tree cover, leaf litter depth and surface stone cover for some species and, for others, to soil compaction, distance to major roads and elevation. Conclusions: The alien ruderal species clustered according to the general climate (temperate vs. tropical). Grasses of African origin are of highest concern as invasive species. Although most introductions are related to human disturbance, each species becomes dominant under certain environmental conditions. Thus, management programs must be specifically adjusted to each individual invasive alien. [ABSTRACT FROM AUTHOR]

Copyright of Cuadernos de Investigación Geográfica is the property of Universidad de la Rioja, Servicio de Publicaciones and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ecosystem dynamics is based on successional processes that occur after anthropic and natural disturbances. The succession of native woody plant species was studied under a plantation of Eucalyptus globulus in Loja, Ecuador; with the objective of determining the floristic composition and monitoring natural regeneration. Five permanent plots of 20 m x 20 m were established to investigate latizales, five subplots of 5 m x 5 m were nested for saplings and five subplots of 1 m x 1 m for seedlings. Height and basal diameter were measured at the beginning of the experiment and at 12 months. Floristic composition and structural parameters were determined at the first sampling time; with the data from the second measurement, survival and growth were evaluated. The influence of the environmental variables: soil depth, slope and luminosity on the floristic diversity and abundance of natural regeneration were analyzed. Twenty-eight species within 24 genera and 21 families were recorded. The abundant species with the highest IVI are: Solanum aphyodendron (seedlings), Miconia obscura (sapling) and Viburnum triphyllum (latizal). Seedlings have a higher survival rate (100 %) and saplings have a lower survival rate (88.55 %). Viburnum triphyllum (seedlings), Verbesina arborea (saplings) and Inga acreana (grassland) showed the highest growth in height. Basal diameter is dominated by Solanum aphyodendron (seedlings), Alnus acuminata (saplins) and Critoniopsis pycnantha (latizal). The floristic diversity present in the latizales correlates with the environmental variables, in the seedlings and saplings there is no significant relationship. [ABSTRACT FROM AUTHOR]

Miconia rufa is considered an endemic species complex from the eastern Cuban mountains, which includes M. plumieriifolia, a taxonomic decision based on the review of only a few herbarium specimens. Recent collections of this taxa allowed the verification of the foliar shape and size differences between populations of Sierra Maestra and Toa ranges, which indicated the need for a more detailed study regarding this subject. In the current paper, we characterized and morphometrically compared leaves among northeast and southwest groups of eastern Cuba, to provide elements that clarify their delimitation. We analyzed 361 leaves from 45 individuals from different herbaria, the length, maximum width and leaf area were measured, and the shape was described by internal angles, shape indexes, landmarks and Fourier contour descriptors. To characterize environmental conditions of source localities, we extracted bioclimatic models and remote sensing data, a set of variables including mean and annual maximum temperatures, precipitations, altitude, slope, tree cover, NDVI, aridity index and evapotranspiration potential from maps. Populations from northeast and southwest parts were statistically different in length and shape of leaves. Except for the type locality of each name, the rest were not markedly different in environmental conditions, but morphometric differences in leaves were associated with environmental differences. Individuals from the Gran Piedra mountain range show extremes properties. Morphometric characteristics from the type collection of M. rufa and M. plumieriifolia were not representative of all population spatial variability, therefore other studies are required to clarify the origin of these spatial morphometric patterns in the leaves differences of this species complex. [ABSTRACT FROM AUTHOR]

Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

El tahalí (Trichiurus lepturus) es un pez que habita fondos someros de sustratos blandos hasta 100 m de profundidad y puede encontrarse cerca de la superficie formando cardúmenes. La flota artesanal de Boca del Río en la isla de Margarita efectúa la captura del tahalí con línea de mano con lámpara de 12 vatios, conocido como "cordel fondero con luz". Debido a la importancia socio-económica que representa la pesca de esta especie en la comunidad, se planteó estimar la captura por unidad de esfuerzo (CPUE) mensual y su asociación con la temperatura superficial del mar, velocidad del viento y precipitación, durante el periodo 2003-2006. La toma de datos de captura y esfuerzo se efectuó en el Sector Caracas donde desembarcó el 16% de la flota pesquera, que osciló de 69 a 78 embarcaciones activas. La CPUE se relacionó con las variables ambientales mediante un Análisis de Componentes Principales. Los resultados mostraron coherencia entre la captura y el esfuerzo pesquero con apreciables fluctuaciones mensuales y anuales; mientras que la CPUE mostró una notable variación intermensual desde 0.25 kg/hora de pesca hasta 23.24 kg/hora de pesca; lo que evidencia una marcada estacionalidad. Se observó una asociación positiva entre la abundancia relativa y la temperatura superficial del mar, y negativa con la velocidad del viento. Estos resultados sugieren que la abundancia relativa estaría regulada fundamentalmente por los factores ambientales del ecosistema pelágico costero. Abstract The largehead hairtail (Trichiurus lepturus) is a fish that inhabits shallow waters of soft substrates, up to 100 m deep, and can be found near the surface forming shoals. The artisanal fishing fleet of Boca del Rio, on Margarita Island, captures largehead hairtails with hand lines attached to a 12 watt lamp, called "lighted bottom lines". Due to the socio-economic importance the fishery of this species represents to the community, it was proposed to estimate the catch per unit effort (CPUE) monthly and its association with the sea surface temperature, wind speed, and precipitation, during 2003-2006. Data on catch and fishing effort were collected in the Caracas Sector, where 16% of the fishing fleet landed, which ranged from 69 to 78 active fishing boats. The CPUE was correlated with environmental variables using Principal Component Analysis. Results showed a relationship between catch and fishing effort with notable monthly and annual fluctuations; while the CPUE exhibited significant monthly variation, from 0.25 kg/hour fishing to 23.24 kg/hour fishing, showing notable seasonality. A positive correlation was seen between relative abundance and sea surface temperature, and negative with wind speed. These results suggest that relative abundance may be affected fundamentally by environmental factors of the coastal pelagic ecosystem. Keywords: Trichiurus lepturus, artisanal fishery, environmental variables, Venezuela.

Background. The CO2 emission flow from the soil, known as soil respiration, is an important pathway in the global carbon cycle. Objective. Thus, the objective of the present was to determine the variation of CO2 emissions according to a) different management before, during and after grazing by cattle; b) influence of environmental and soil factors on emissions, as well as c) adjust a model and assess its sensitivity to dimension the applicability in soil respiration behavior. Methodology. The soil respiration was measured every 30 min for 312 hours followed by a closed dynamic chamber of known volume placed on the floor, integrated with an infrared gas analyzer (Model 8100-104). Results. The results indicate that the total emissions in each management were 228, 128 and 241 kg CO2 ha-1 day-1 in an agroforestry system with fruit trees before, during and after grazing, respectively. The ambient temperature influences the respiration of the soil in the three ways. While soil moisture affects only during and after grazing. Implications. Since the results are limited, it is important to evaluate and analyze for long periods of time to understand the behavior of the R in agroforestry systems. Conclusion. In the sensitivity analysis, the increase of 2 ° C and 20% in variables such as precipitation, soil temperature and soil moisture would favor the increase of the CO2 flow from the soil to the atmosphere.

Se analizó la variación en la composición taxonómica y densidad de las especies de la comunidad de c1adóceros planctónicos de una laguna de baja salinidad de la provincia de La Pampa, mediante muestreos mensuales a lo largo de un ciclo anual. La diversidad y la riqueza específica fueron mayores que en otros ambientes provinciales, probablemente debido al bajo contenido de sales del agua. Se registraron nueve especies: Moina micrura Kurz, 1874, Bosmina huaronensis Delachaux, 1918, Afona sp. Baird, 1843, Macrothrix sp. Baird, 1843, Leydigia leydigi Schoedler, 1863, Ceriodaphnia cf. dubia Richard, 1895, Daphnia cf. obtusa Kurz, 1874, Daphnia spinulata Birabén, 1917 y Diaphanosoma birgei Korínek, 1981. Se verificó el predominio de B. huaronensis, especie típicamente planctónica, pero el ticoplanctonte Alona sp. también alcanzó densidades muy altas. Se menciona la presencia de D. birgei, especie que había sido registrada en cuerpos de agua de la provincia con características físico-químicas distintas a las de esta laguna. La mayor parte de las especies detectadas fue de pequeño tamaño, probablemente debido al efecto de la predación selectiva por parte de peces.

La combinación de factores bióticos y abióticos (clima, orografía, litología, competencia interespecífica, etc.) y la patogenicidad de agentes como el hongo Phytophthora cinnamomi Rands han generado la enfermedad fitosanitaria denominada en España como la seca de encinas y alcornoques de la Península Ibérica. El objetivo del presente estudio es el análisis que desempeñan las variables ambientales en el desarrollo de dicha enfermedad y determinar cuáles tienen una mayor influencia en su propagación. Se toma como área de estudio el Monte de Valdelatas, Alcobendas, Madrid (hoja 534 del Mapa Topográfico Nacional a escala 1:50.000. Coordenadas UTM X: X: 442592.51, Y: 4487266.63 zona 30T). Se obtivieron muestras en campo de 100 árboles de Quercus ilex subsp. ballota (50 con apariencia saludable y 50 con síntomas aparentes de enfermedad) azarosamente ubicados en 7 transectos. En relación al modelo estadístico se empleó un modelo binomial cuya variable respuesta se definió como sano/enfermo, según la apariencia del árbol. Así mismo, se manejó el Criterio de Información de Akaike (AIC) con el fin de establecer el mejor modelo. En su caso, presentando un 44% de la varianza (D2 = 0.437) y un valor de 89.68 en AIC. Las principales variables ambientales que interfieren en la enfermedad fueron: proximidad a cursos fluviales, índice de humedad topográfico, cobertura de Daphne gnidium y Quercus ilex subsp. ballota y la edad de los individuos muestreados. Dada la pérdida en la masa forestal de Quercus debido a la enfermedad de la seca, es necesario comprender el comportamiento de dicha enfermedad, así como conocer los factores ambientales que contribuyen a su expansión, pudiendo llegar de tal modo a identificar algún factor inhibidor. The combination of biotic and abiotic factors (climate, orography, lithology, interspecific competition, etc.) and the pathogenicity of agents such as the fungus Phytophthora cinnamomi Rands has generated the phytosanitary disease known as the oak decline (la seca) in holm oak and cork oak stand of the Iberian Peninsula. The aim of this study is to analyse the role played by environmental variables in the development of this disease, and to determine which have a stronger influence in the spread of the disease. Data has been obtained from Monte de Valdelatas, Alcobendas, Madrid (sheet 534 national topographic map, scale 1:50.000, UTM coordinates X: 442592.51, Y: 4487266.63 zone 30T). Field samples were taken from 100 randomly selected Quercus ilex subsp. ballota individuals (50 with a healthy appearance and 50 that showed disease symptoms), located within 7 transects. In relation to the statistical model, in this work a binomial model was used. On it, the response variable was defined as healthy/unhealthy, depending on the appearance of each tree. Akaike Information Criteria (AIC) was used to define the quality of the model. We selected model obtained a score of 89.68 and accounts for approximately 44% of data variability (D2 = 0,437). The main environmental variables that impact disease were: proximity to river course, topographic wetness index, cover of Daphne gnidium and Quercus ilex subsp. ballota, and the age of the individuals. Given the loss of Quercus forest mass caused by the spread of the oak decline disease, detected in several countries, including Spain, it becomes necessary to adequately understand the different factors that contribute and, in some cases, is the cause of the expansion of the disease, as well as to identify any inhibiting factors.

Introduction: Zooplankton is a major link between primary producers and the following trophic levels, and in coral reefs they represent an energy source for corals and involve complex assemblies integrating a wide variety of species form different functional groups. Objective: To define interannual changes in zooplankton assemblies in coral reefs of Isla del Coco. Methods: Three coral reefs system were sampled. Two or three samples were taken by surface horizontal trawls in each coral reef from 2009 to 2012, using conical zooplankton nets of 200 and 500 μm mesh sizes at different times of the day. Physical and chemical variables were measured before zooplankton sampling. Results: We identified 24 taxonomic groups of macrozooplankton and 22 of mesozooplankton. Copepods were the most abundant taxa (87.1%) of the total abundance of mesozooplankton and macrozooplakton (58.9%); however, chaetognaths (35.6%) exceeded copepods (35.4%) in abundance in macrozooplankton samples during 2011. Mesozooplankton samples showed higher abundance (68753.2±9123.2 ind m-3) and biomass (85.14±11.3 mg DW m-3) than macrozooplankton samples (4454.9±751.0 ind m-3, 22.8±3.8 mg DW m-3). The interannual macrozooplankton community structure did not change significantly (ANOVA, p=0.368), but did change for mesozooplankton (ANOVA, p=0.001). Variations in physical and chemical variables influenced the community structure for both meso and macrozooplankton, increasing or decreasing organism abundance. Conclusions: Coral reef zooplankton of Isla del Coco resembles that of other coral reefs under the influence of oceanic conditions, with a fauna formed mainly by calanoid copepods, chaetognaths and appendicularians, and depending on oceanographic conditions, the abundance of these groups can change. [ABSTRACT FROM AUTHOR]

This article presents the evaluation of the parameters of Electrical Safety in its general requirements, for biomedical equipment and electronic instrumentation, according to the regulations of the International Electrotechnical Commission, IEC, for uncontrolled environmental laboratory conditions, such as the temperature and the percentage of relative humidity. This evaluation is done to implement a protocol for preconformity tests and in situ fault detection for electro-technology equipment. Eighteen equipment were evaluated, including biomedical and instrumentation. After that a correlation analysis of the environmental variables was performed with the measured parameters, to determine the influence of the environmental variables on the Electrical Safety parameters. The results show that such parameters do not present any correlation with the measured environmental variables. [ABSTRACT FROM AUTHOR]

This review paper makes part of the applied research project "Design and implementation of a SCADA system to control the water resources and associated environmental parameters through PLC in greenhouses" ascribed to the research group GICEMET in the National Learning Service-SENA-. This study aims at identifying the applications of the agricultural automation to include models of supervision, control and information acquisition in the water resources and environmental parameters management for crops cultivated in greenhouses. A comprehensive search was carried out in national and international indexed journals, webpages and databases. The information was categorized based on several differentiated criteria: supervision under greenhouses, automatic control of water resources and environmental parameters, information acquisition for irrigation under greenhouses, and technological tendencies of the automation in the field. This review allowed to conclude about the advantages of the implementation of this kind of automation compared to conventional agricultural systems, as well as, poses the necessity to apply it in the agricultural sector as a contribution to reduce the impact of the workforce migration from the rural areas to the urban areas.e. [ABSTRACT FROM AUTHOR]

Copyright of Revista Chapingo Serie Ciencias Forestales is the property of Universidad Autonoma Chapingo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mosquitoes (Diptera: Culicidae) are important vectors of diverse pathogenic organisms, particularly arboviruses and protozoa. The immature stages of mosquitoes occur in a wide range of natural or human-made aquatic habitats. On this basis, some anthropogenic places such as cemeteries, usually serve as thrive and productive artificial-breeding habitats for mosquitoes. Despite being important foci for vector species, urban cemeteries are frequently overlooked in control and surveillance programs. This study evaluates the association of ecological variables and attributes (type of material, presence of flowers, water availability and height from the ground) of the breeding sites with the levels of infestation of mosquito immature stages. In 2017, an entire urban cemetery in Jarabacoa (Dominican Republic) was sampled at two different climatic periods (March: dry and August: rainy) for the characterization of the artificial breeding-sites, collection of immature stages of culicids and subsequent laboratory rearing for species identification. In total 968 containers were studied, containing 7 758 immature stages in 203 (21.0%) water-filled containers which accounted for four species: Culex quinquefasciatus (50.5%), Aedes aegypti (47.1%), Aedes albopictus (1.9%) and Culex nigripalpus (0.4%). The mean of A. aegypti immatures in infested containers was roughly two times higher compared to C. quinquefasciatus and significantly lower compared to A. albopictus. The total Container Index (CI) was 20.9%, and among the type of materials, those made from rock (cement, ceramic, and mud) and plastic had the highest CI = 25.9% and 23.4%, respectively. Almost 95% of the total infested water-filled containers were made of plastic or rock. No association was found between the type of material of the containers and the density of mosquitoes. However, overall, greater densities of immature stages were found at ground than at higher levels. A weak positive correlation between water volume and density was found in some species of immature stages. Significantly higher number of C. quinquefasciatus were recorded in containers with flowers and large water volume. In contrast, A. aegypti immature stages were more frequent in containers without flowers. A weak negative association between water volume and infestations was found for A. albopictus immatures. As reflected of their opportunistic behaviour and broad ecological plasticity, Culex spp. and Aedes spp. mosquitoes were abundant pests in cemetery habitats where were able to breed in almost any kind of water-filled container regardless the type of material. However, our study showed that some ecological variables have critical impact for the development of the immature stages of some species. The health authorities and cemetery keepers can benefit from these results by focusing on the implementation of detailed plans and integrated strategies for the control and prevention of cemetery infestations by mosquitoes. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Los macroinvertebrados acuáticos representan un componente importante en los sistemas de agua dulce por su alta abundancia y diversidad, con relación a otros grupos biológicos. En estos sistemas acuáticos, muchos macroinvertebrados desarrollan gran parte de su ciclo de vida. Por lo anterior, el estudio de este grupo tiene gran importancia en temas de ecología de los sistemas acuáticos. El objetivo de este estudio fue caracterizar las comunidades de macroinvertebrados acuáticos asociados a la ciénaga Sahaya, en el departamento del Cesar y en tres de sus afluentes. En la ciénaga se recolectó el material biológico utilizando draga ekman y en los afluentes mediante red Surber. Se encontraron 6431 organismos, distribuidos 15 órdenes, 28 familias y 47 taxones. Del total de individuos, 5671 (88,2 %), se recolectaron dentro de la ciénaga y los 760 individuos restantes (11,8 %) en los afluentes evaluados. Se encontró que la familia con más abundancia fue Caenidae, con 1859 individuos, seguida por Naididae con 1691 y Chironomidae con 1122. La estructura de macroinvertebrados fue diferente en los cuerpos de agua corriente, de igual forma varió espacialmente entre las estaciones de la ciénaga y de los tres afluentes. En la ciénaga se evidenciaron posibles asociaciones entre la abundancia de algunos grupos de macroinvertebrados y las variables ambientales, hecho que parece confirmar el potencial de estas comunidades como indicadores de la calidad ecológica de las aguas.

Este trabajo estudia los tamaños corporales de las poblaciones modernas de Lama guanicoe de Patagonia continental e insular (Argentina), a partir del análisis osteométrico de cuatro huesos largos delanteros (húmero, radiocúbito, metacarpo y primera falange). Se analizó una muestra de más de 100 individuos procedentes de las provincias de Río Negro (40°S), Santa Cruz (48-52°S) y Tierra del Fuego (53-54.5°S). Las variaciones morfológicas de los tamaños se evaluaron en función de las variables ecoambientales de: temperatura (máxima/mínima), precipitación (estival, invernal y anual), productividad primaria neta aérea (PPNA) e índice de vegetación diferencial normalizado (NDVI). Los datos fueron procesados mediante diferentes análisis uni y multivariados. Los resultados demostraron que, en una escala macroregional, se registra un gradiente clinal de los tamaños corporales de las poblaciones de guanacos (los individuos de Tierra del Fuego son significativamente más grandes que los de Santa Cruz y éstos más grandes que los de Río Negro). Todos los factores ecoambientales que se asocian fuertemente con los tamaños óseos (temperatura máxima, PPNA, NDVI) covarían en la región de estudio con la latitud. El patrón clinal observado es, en principio, consistente con las expectativas derivadas de la Regla de Bergmann. Igualmente las diferentes variables ambientales y biogeográficas que influyen sobre los patrones de los tamaños de los guanacos modernos de Patagonia, exponen que la relación entre el tamaño corporal y el ambiente es de naturaleza compleja y no se puede explicar de forma simple y directa por un solo factor.

El objetivo del presente trabajo fue evaluar los impactos ambientales significativos generados por la actividad de la empresa Alpes Chiclayo S.A.C. en la producción de conserva de frijol de palo, midiendo las variables ambientales: la calidad del aire para medir NO2, O3, SO2 y H2S de acuerdo a lo contemplado en el D.S. 074-PCM, niveles de ruido en los diferentes puntos de la planta, material particulado midiendo los parámetros MP10 y MP2.5 y la calidad de agua fue determinada por el método de Plasma Inducido Acoplado (ICP). Para evaluar los impactos ambientales se utilizó el método de matrices bidimensionales que plotea acciones versus factores ambientales y utilizando el método de Fisher Davies se calificaron los impactos ambientales negativos en una escala de poco significativo, significativo y muy significativo, severo y critico anteponiendo el signo (-). Para los impactos positivos se antepuso el signo (+). Los resultados del monitoreo realizado utilizando el método de matriz bidimensional determinó que los impactos ambientales generados durante el proceso productivo fueron calificados como poco significativos; los impactos positivos fueron sobre la población, agua, suelo y paisaje. Los impactos negativos fueron sobre el suelo, agua y aire. Se concluyó que para mitigar los impactos ambientales identificados se ha elaborado el Programa de Adecuación y Manejo Ambiental (PAMA) para la empresa, orientado al logro del desarrollo sostenible y al paradigma basura cero con la finalidad de mejorar la calidad de vida de la población y del ambiente.

Caddisflies are abundant, diverse, and important insects in freshwater ecosystems. However our knowledge on their life history is incomplete, in particular for the Neotropics. The objectives of this study were to describe the life history and phenology of Phylloicus pulchrus in the Luquillo Experimental Forest, Puerto Rico. Eggs and larvae were reared to determine the species lifespan and time in each instar. Larval instars were determined based on a head width vs. pronotal suture length correlation (N= 120). Larvae and benthic leaf litter were sampled monthly at a headwater stream for a year; all specimens were classified into instars based on their case size. Adult P. pulchrus were sampled monthly for a year with a light trap and at various times with a Malaise trap. Monthly environmental variables were related to species and sex abundance. There was a gradient of egg development where eggs (within compound masses) closest to the water were more developed. There were five larval instars and reared larvae showed longer development times and more variable body measurements in later instars. The best correlation for larval instar determination was case length-head width (Pearson= 0.90, P= 2.2e-16, N= 120). Phylloicus pulchrus has a multivoltine life cycle, with asynchronous larval development. Adult abundance was low. First to third instar larvae were influenced significantly by rainfall and rainfall seasonality had a negative significant effect on second instar larval abundance (ANOVA= 7.45, P= 0.02).Compound egg masses were probably oviposited by different females that gathered for oviposition. Phylloicus pulchrus follows the predominant developmental characteristic of Trichoptera of having five larval stages. Development times were longer than expected (longest times for a Phylloicus species) and may be an effect of laboratory rearing. The influence of rainfall (and seasonality) on different larval instars highlights the importance of this variable on early larval development. The cause of low adult abundance remains unclear, but may be related to low emergence rates and trap efficiency. [ABSTRACT FROM AUTHOR]

The distribution and abundance of fish is influenced by multiple factors at temporal and spatial scales, and their community composition represent good river integrity indicators. The main objective of this study was to describe the composition and structure of fish assemblages along the Anchique river sub-basin (that drains to Magdalena river), and to test the hypothesis that these communities vary temporally and spatially. For this, four sites (E1, E2, E3 and E4) were sampled along the river (from river birthplace to Magdalena river), during the periods of high and low waters, in 2014. In each site, longitudinal transects (100 m long x 2 m wide, 60 min) were established and fishing was made with both electrofishing and trawl (10 m x 1 m, 0.05 m) nets. Fish samples were fixed and transported to the laboratory for posterior taxonomic identification with the use of keys; fish diversity and structure composition were calculated with the use of standard models. Besides, substrate composition and environmental variables were also considered. A total of 652 fish belonging to 36 species were recorded; high water showed higher values (325 fish with 32 species) than low water period (300 fish with 31 species). Siluriformes was dominant (51 %), followed by Characiformes (32 %), Gymnotiformes (5 %), Cyprinidontiformes and Cichliformes (6 %). Most abundant families were Characidae (28.3 %; 9 spp.), Loricariidae (23.4 %; 8 spp.) and Trichomycteridae (15.0 %; 2 spp.). Kruskal-Wallis test indicated that there is no significant difference among some environmental variables at the temporal level. The values of structural complexity and substrate composition indices showed that E4 had the highest values (0.8), followed by E1 (0.6), and E2 and E3 (0.4). Moreover, E4 had the highest richness and diversity, according to Hill's number. The canonical correspondence analysis showed that the substrate, and the complexity and width of the river channel, had a significant influence on fish composition and distribution. The fish community richness and diversity did not change temporarily, but did spatially, which could be related to the different structural features of sampling sites. Rev. Biol. Trop. 66(1): 336-351. Epub 2018 March 01. [ABSTRACT FROM AUTHOR]

Worldwide big cats are at risk of extinction, and anthropogenic factors and natural habitat disturbances represent the biggest threats for their survival. It is essential to know the natural resources use by these predators and the way these big felids can adapt to changes. It is unknown how the puma (Puma concolor) selects and uses resources, what environmental factors determine its presence and how this species is affected by natural disturbances in Mexican tropical forests. This study was performed in the Eden ecological reserve and surroundings, in the North of Quintana Roo, Mexico, an area dominated by tropical semideciduous (medium forest) and secondary forest (acahual). Camera samplings were carried out during 2008, and from 2010 to 2012. Habitat variables, activity patterns and species associations were also spatially and temporally analyzed using achi-squared test and overlapping coefficients. General Linear Models(GLM) were used in order to determine which variables influence the presence of cougars in the study area. Cougars used vegetation and paths in different proportions as the availability of these resources. The years with more changes (P <0.05) were 2008 and 2011. This predator was active throughout the day, but changed its activity patterns over the years. The cougarwas spatio-temporally associated with six mammals and two big terrestrial birds:Pecari tajacu (Δ = 0.52), Meleagrisocellata (Δ = 0.55), Crax rubra (Δ = 0.58), Didelphis sp.(Δ = 0.64), Mazama temama (Δ = 0.66), Leopardus pardalis (Δ = 0.68), Dasypus novemcinctus (Δ = 0.73) and Panthera onca (Δ = 0.87). After testing 90 GLM models, the model with a lower AIC value described the activity patterns of prey and co-predators. The vegetation and water in the reserve were important variables for the cougar. However the variables that determined and modified the presence of the species were activity patterns of co-predators and the potential preys. The factors that negatively affected the presence of the species were fire, human presence, and habitat displacement to less favorable habitats to avoid jaguar. Rev. Biol. Trop. 66(1): 78-90. Epub 2018 March 01. [ABSTRACT FROM AUTHOR]

Copyright of Espacio, Tiempo y Forma: Serie VI, Geografía is the property of Editorial UNED and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Colombiana de Ciencias Hortícolas is the property of Revista Colombiana de Ciencias Horticolas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The suprabenthos or hyperbenthos is the macrofaunal assemblage of small-sized organisms that interact for some time in the benthic boundary layer. Information about the taxonomic composition and role of suprabenthic species, especially in littoral zones, is scarce and scattered. This work attempts to contribute alleviate this problem. We analyze the temporal and spatial variations of suprabenthic assemblages in the swash-zone from four beaches of the littoral coast of Venezuela. For each beach, two sites were chosen, and special attention was given to water and sediment characteristics. 12 environmental variables were measured: Dissolved oxygen, oxygen saturation percentage, pH, salinity, surface temperature, total, organic and inorganic suspended solids, total organic carbon, organic matter in sediment, grain size of sediment, and amount of dragged material of sample. All faunal samples were taken on a monthly basis during 2011; these were extracted using a manual suprabenthic sledge towed parallel to the shoreline. Samples were sorted and identified to their lowest possible taxonomic level. A total of 24 141 specimens (mean abundance: 26.16±55.35ind./m²) belonging to 21 taxonomic groups were identified. Analysis suggests that seasonality does not explain observed changes either in fauna or environmental variables. It was found that suprabenthic assemblages, total suprabenthos density, richness and environmental variables changed in a dissimilar fashion between months and beaches. The most frequent groups were amphipods and decapods; and at the species/categories level post-larval shrimp (Penaeidae), Grapsidae crab megalopae and Arenaeus cribarius megalopae were common. Dissimilarity between months in each beach was primarily explained by the abundance of amphipods, ctenophores, decapods and mysids. For particular months and selected beaches very high abundances of ctenophores were found. This group dominated the sample even though it is not usually a representative group in suprabenthos. Samples showed low correlations between suprabenthos and environmental variables. A somewhat stronger correlation could be established between water characteristics and dragged material abundance. The studied suprabenthos assemblage was found to have high taxa richness and very dynamic behaviour at spatial and temporal scale. Further analysis suggested that there is no evident pattern of distribution and that causality can not be directly attributed to temporal variation only. Possibly there is an influence of a synergy of environmentals or biological factors, rather than a single variable. The species Americamysis bahia and Americamysis taironana are reported for the first time in Venezuela. This study represents the first ecological research of the suprabenthos in the Caribbean region.

For a sample of 25 cities from different countries, information was collected on the annual air quality for PM2.5, NO2 and ozone and also on various parameters of interest as to their potential relation with air quality. A comparative analysis of this information and a linear model that relates the air quality to some of the parameters was elaborated, based on the level of approximation found between the air qualities reported and those predicted by the modeling. The data are based on reports and information available on websites and public reports and also on research reports done by the authors for the years 2012 and 2015. With this comparative analysis it has been possible to present a novel perspective on the air quality situation of the city and on the type of strategic measures that could be taken to improve the air quality situation [ABSTRACT FROM AUTHOR]