Browsing Artículos científicos by Title
Now showing items 481-500 of 555
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Selección de plantas para el control de la erosión hídrica en Costa Rica mediante la metodología de criterio de expertos
(Centro Agronómico Tropical de Investigación y Enseñanza (CATIE) (Costa Rica), 2011)En Costa Rica, la utilización de plantas para el control de la erosión es escasa y poco documentada. Este estudio identificó, mediante la metodología de criterio de expertos, especies vegetales utilizadas para dicho ... -
Serpocaulon orosiense, a New Hybrid of Serpocaulon (Polypodiaceae) from Costa Rica
(Universidad Nacional (Costa Rica), 2021-11-08)Se han descrito cuatro híbridos entre especies de Serpocaulon, uno de ellos S. × sessilipinnum fue el único híbrido conocido entre dos clados diferentes propuesto por Smith et al. En este trabajo se describe un nuevo híbrido ... -
Shifts in bacterioplankton community structure between dry and wet seasons in a tropical estuary strongly affected by riverine discharge
(Elsevier (Países Bajos), 2023-12)Estuaries are among the most productive ecosystems in the world and are highly dynamic due to the interaction of freshwater and seawater, which results in strong spatial gradients in physico-chemical conditions. ... -
Simulación de una cohorte de Anchoa Panamesis (Steindachner, 1975) en el Golfo de Nicoya, Costa Rica
(Universidad Nacional [Costa Rica], 1987-01-01)Se aplica el modelo de simulación de stock de Jansen a una cohorte hipotético de 100.000 peces de Anchoa panamensis, utilizando una tasa de mortalidad natural de 0.274 mensual, obtenida para esta población en 1981 y dos ... -
Skin texture change in diasporus hylaeformis (Anura: Eleutherodactylidae
(Sociedad Herpetologica Mexicana, 2020-11)La Rana Martillito de Altura, Diasporus hylaeformis, fue observada mostrando un cambio de textura de la piel durante una sesión fotográfica. Se ha sugerido que este comportamiento, reportado recientemente en anuros, puede ... -
Snake diversity (squamata: Serpentes) in Quebrada González sector of Braulio Carrillo National Park, Costa Rica
(Malcolm L. McCallum, 2019-04-30)Within Braulio Carrillo National Park (BCNP) of Costa Rica, there is a lack of quantitative data regarding the snake community despite its informally reported abundance and relevance to human health. The objective of this ... -
Social effects in growth experiments. Growth of jaguar guapote (Cichlasoma managuense) in isolation and in small groups
(Universidad Nacional (Costa Rica), 1997)Se evaluaron el crecimiento y la conversión alimenticia de juveniles de guapote tigre (Cichlasoma managuense) mantenidos a densidades constantes de 1, 2, 5, 10 y 20 individuos por pecera. La densidad mostró una correlación ... -
Spatial variation of physicochemical parameters in a constructed wetland for wastewater treatment: An example of the use of the R programming language
(Universidad Estatal a Distancia (Costa Rica), 2021-06)Introduction: The implementation of wastewater treatment systems such as constructed wetlands has a growing interest in the last decade due to its low cost and high effectiveness in treating industrial and residential ... -
Species diversity and distribution of genus Pampus (Pelagiaria: Stromateidae) based on global mitochondrial data
(Universidad Nacional (Costa Rica), 2022-12-13)Due to the highly similar external morphology of the Pampus species, misidentifications frequently occur and hinder the understanding of the taxonomy and species distributions of the genus. In this study, we generated 271 ... -
Spontaneous spawning in captivity of the first generation hatchery-produced weakfish, Cynoscion squamipinnis (Perciformes: Sciaenidae)
(Universidad Nacional (Costa Rica), 2017-01)The aim of this study was to evaluate the spontaneous spawning of the first generation of weakfish (Cynoscion squamipinnis) reared in captivity in order to conduct restocking programs and mariculture projects. Juveniles ... -
Spontaneous spawning, ontogeny and growth in captivity of Cynoscion squamipinnis
(Universidad de Costa Rica, 2016-09-03)The croakers or drums are commercial species, which have been overfished in the Nicoya Gulf, Costa Rica. This study aimed to describe, for the first time, the reproduction and the ontogeny of weakfish, Cynoscion squamipinnis ... -
Spotted rose snapper (Lutjanus guttatus) aquaculture research and development as socio-economic alternative for Costa Rican fishing communities
(2010-06-01)The spotted rose snapper (Lutjanus guttatus) is one of the main target coastal species, but landings are decreasing in quantity and size. Reports include a mean capture size of 50 cm with gill nets and 38 cm with bottom ... -
Strategy of bioremediation in recirculating aquaculture systems using constructed microbial mats
(Journal of Chemical, Biological and Physical Sciences, 2014-11-30)Due to strict international standards, every day there is greater interest in developing environmentally sound treatment systems in aquaculture facilities that can remove contaminants from effluent and allows for the reuse ... -
Surface-Water Quality of the Gulf of Papagayo, North Pacific, Costa Rica
(Universidad Nacional, Costa Rica, 2021-08-25)In recent years, the northwestern part of the North Pacific areas of Costa Rica has undergone rapid socioeconomic development. This situation, combined with the scarce available information about the water quality of the ... -
Sustainability assessment based on stakeholders’perceptionof tourism activities in Loreto Bay National Park, Mexico
(Centro de Investigación en Alimentación y Desarrollo, A. C, 2022-11-22)Objective: To assess the level of sustainability, based on stakeholders’ tourism perceptions of Loreto Bay National Park (LBNP) in Mexico. Methodology: Indicators were selected and organized in three components: (1) ... -
Tamaños y proporción sexual de Ucides occidentalis (Crustacea: Gecarcinidae) en un manglar de Costa Rica
(Universidad Nacional (Costa Rica), 1995-02-22)Sizes and sex ratios of Ucides occidentalis (ORT-MANN 1897) were studied in the mangrove area of Estero Panama, Guanacaste, Costa Rica, from March to August 1982. The caparace length was 36.7-84.5 mm for males and 36.00-60.8 ... -
Tasa de filtración del ostión de manglar, ( Crassostrea rhizophorae, Guilding 1828), a diferentes salinidades y temperaturas
(Universidad de Costa Rica (Costa Rica), 1985-06-01)Se analizaron los valores de la tasa de filtración con rojo neutro en 60 ostras de mangra, Crassostrea rhizophorae, en dos experimentos; uno con salinidades de 10, 20, 25, 30 y 35%0 a una temperatura constante de 24°C y ... -
Technical and economic feasibility of adding pure oxygen for rotifer production (Brachionus plicatilis) spotted snapper (Lutjanus guttatus) larvae feeding
(Tecnológico de Costa Rica (TEC) (Costa Rica), 2016-08-30)A study to technically and economically evaluate the addition of pure oxygen in a culture of rotifers for feeding marine fish in the Pacific Marine Park, Puntarenas, Costa Rica was performed. The results showed no ... -
Tecnologías para la rehabilitación en una microcuenca urbana
(Universidad Estatal a Distancia (Costa Rica), 2016-05-17)La degradación de los ecosistemas acuáticos urbanos que incluye ríos y quebradas ha provocado la pérdida de biodiversidad, disminución de la calidad ambiental y la afectación de la calidad de vida de los habitantes de ... -
Tendencias en las concentraciones de nitratos y determinación de sus orígenes usando isótopos estables (18O y 15N) en el agua subterránea de la parte oeste del Valle Central, Costa Rica
(2013-08-22)El nitrato es el contaminante más común en el agua subterránea y se deriva principalmente de la lixiviación de fertilizantes sintéticos y desde sistemas in situ de disposición de aguas negras, especialmente en áreas con ...