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1.
Rev. biol. trop ; Rev. biol. trop;72(1): e57968, ene.-dic. 2024. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1583373

ABSTRACT

Resumen Introducción: Recientes investigaciones han mostrado correlaciones positivas entre la estructura del hábitat y las comunidades animales que los habitan. Generalmente, estos estudios evalúan la hipótesis de una mayor diversidad de animales en hábitats complejos y heterogéneos, ya que éstos pueden ofrecer un mayor número de nichos potenciales a diferencia de aquellos estructuralmente más simples. Objetivo: Se evaluó el efecto de la complejidad, la heterogeneidad y la estructura del hábitat sobre una comunidad de mariposas diurnas (Papilionoidea) en tres tipos de coberturas vegetales (rastrojo, bosque y páramo) ubicadas en ecosistemas de alta montaña sobre la cordillera Central, departamento de Antioquia, Colombia. Métodos: Entre enero y julio del 2012, se realizaron capturas de mariposas utilizando trampas Van Someren Rydon y se cuantificó la complejidad, la heterogeneidad y la estructura de la vegetación a partir de parcelas circulares de 0.04 ha establecidas alrededor de las trampas. Resultados: Se reportó un total de 108 especies, 48 géneros y cinco familias de mariposas. La riqueza y la abundancia de especies de mariposas fueron sensibles tanto a la complejidad y heterogeneidad de las coberturas vegetales como a los cambios en la estructura de la vegetación, mostrando fuertes correlaciones con las características del hábitat. El rastrojo presentó la mayor diversidad de mariposas (1D = 25.02; 2D = 11.97), seguido por el bosque (1D = 15.83; 2D = 9.42) y el páramo (1D = 12.36; 2D = 7.86). Adicionalmente, la riqueza y abundancia de mariposas se asoció positivamente con la cobertura de dosel y la densidad de vegetación de los estratos verticales y horizontales. Conclusión: Estos resultados subrayan la importancia de conservar la heterogeneidad de los hábitats y la estructura vegetal en los ecosistemas de alta montaña andinos, para mantener la diversidad y abundancia de las mariposas, resaltando la necesidad de políticas de conservación y manejo que consideren la complejidad y diversidad de estos ecosistemas.


Abstract Introduction: Recent ecological studies have found a positive correlation between habitat structure and animal communities that inhabit them. Generally, such studies try to test the hypotheses that animal species diversity increases in complex and heterogeneous habitats since they may provide more potential niches that structurally simpler habitats. Objective: In this research, the effect of habitat complexity and heterogeneity, and structural habitat characteristics on the butterfly community (Papilionoidea) inhabiting three vegetation covers (shrubs, highland forest and paramo) was evaluated in high-montane ecosystems of the Central Cordillera, Antioquia department, Colombia. Methods: From January to July 2012, butterflies were systematically sampled using Van Someren Rydon traps. Simultaneously, complexity, heterogeneity, and vegetation structure were quantified using 0.04 ha circular plots established around the traps. Results: We reported 108 species, 48 genus and five families of butterflies. Butterfly richness and abundance were sensible to both complexity and heterogeneity of the vegetation covers, as well as to changes in the vegetation structure, showing strong correlations with habitat characteristics. Butterfly diversity was highest in the shrub habitat (1D = 25.02; 2D = 11.97), followed by the highland forest (1D = 15.83; 2D = 9.42) and paramo (1D = 12.36; 2D = 7.86). Moreover, richness and abundance of butterfly species were positively associated with the increase in canopy cover and vegetation density in horizontal and vertical strata. Conclusion: These findings underline the importance of preserving the heterogeneity of habitats and vegetation structure in the Andean high-montane ecosystems to maintain the diversity and abundance of butterflies, highlighting the need for conservation and management policies that consider the complexity and diversity of these ecosystems.

2.
Rev. biol. trop ; Rev. biol. trop;72(1): e56175, ene.-dic. 2024. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1583375

ABSTRACT

Abstract Introduction: Levee forests exhibit a vertical stratification that may contribute to structural complexity allowing a great diversity of birds to thrive on the islands. In deltaic ecosystems there is scarce or no data to prove it. Objectives: To assess variations in the composition of the bird community within levee forests. Methods: Two areas of protected wetlands belonging to the Paraná River Delta in Argentina were sampled for three years. A comparative analysis of richness, abundance, and diversity was performed in different levee forests using the point count method. Results: Three distinct types of levee forests -open, intermediate, and closed- were identified based on the structure of their vegetation, hosting a total of 85 bird species. Variation in avian community structure among forest types revealed greater diversity in open forests during winter (3.26 ± 0.13, P < 0.01) and spring (3.58 ± 0.05, P < 0.01), and greater richness in autumn (35.33 ± 3.01, P < 0.01). The closed forests exhibited increased diversity during autumn (3.16 ± 0.13, P < 0.05) and summer (3.24 ± 0.06, P < 0.05), along with elevated abundance in autumn (114 ± 13.70, P < 0.05) and richness in spring (39.17 ± 4.71, P = 0.01). Due to the evolutionary history between sites, significant variation was observed in the most recently created national park, influencing abundance in winter (141 ± 22.06, P < 0.01) and spring (176 ± 12.83, P < 0.01), as well as diversity in winter (3.25 ± 0.10, P < 0.01) and spring (3.50 ± 0.10, P < 0.01). Conclusions: The microhabitat in the different levee forests allows the birds to organize differently. Focusing on microspatial dynamics is key to a deep understanding of the biological processes within subtropical islands and to plan conservation strategies and demonstrate the transition of a recovering riparian forest towards its natural state, where the pulse of the river and the effect of seasonality do not stop operating.


Resumen Introducción: Los bosques de albardón exhiben una estratificación vertical que puede contribuir en la complejidad estructural, permitiendo que una gran diversidad de aves prospere en las islas. En ecosistemas deltaicos hay escasos datos que lo demuestren. Objetivos: Evaluar las variaciones en la composición de la comunidad de aves dentro de los bosques de albardón. Método: Se muestrearon durante tres años, dos áreas protegidas de humedales pertenecientes al Delta del Río Paraná, Argentina. Se realizó un análisis comparativo de riqueza, abundancia y diversidad de aves en tres diferentes bosques de albardón, utilizando el método de conteo por puntos. Resultados: Tres distintos tipos de bosque de albardón -abiertos, intermedios y cerrados- fueron identificados con base en la estructura de su vegetación, hospedando un total de 85 especies de aves. La variación en la estructura de la comunidad de aves entre tipos de bosque revela mayor diversidad en bosques abiertos durante el invierno (3.26 ± 0.13, P < 0.01) y la primavera (3.58 ± 0.05, P < 0.01), y mayor riqueza en otoño (35.33 ± 3.01, P < 0.01). Los bosques cerrados exhibieron mayor diversidad en el otoño (3.16 ± 0.13, P < 0.05) y en verano (3.24 ± 0.06, P < 0.05), junto con elevada abundancia en otoño (114 ± 13.70, P < 0.05) y elevada riqueza en primavera (39.17 ± 4.71, P=0.01). Debido a la historia evolutiva entre sitios, se observó variación significativa en el parque nacional de más reciente creación, influyendo en la abundancia del invierno (141 ± 22.06, P < 0.01) y de la primavera (176 ± 12.83, P < 0.01), así como en la diversidad en el invierno (3.25 ± 0.10, P < 0.01) y en la primavera (3.50 ± 0.10, P < 0.01). Conclusiones: El microhábitat en los diferentes bosques de albardón permite a las aves organizarse diferencialmente. Enfocarse en la dinámica microespacial es clave para una comprensión profunda de los procesos biológicos dentro de las islas subtropicales, planificar estrategias de conservación y evidenciar la transición de un bosque ripario en recuperación hacia su estado natural, donde el pulso del río y el efecto de la estacionalidad no dejan de operar.

3.
Article | IMSEAR | ID: sea-241165

ABSTRACT

Aims: The aim of this study was to examine the vegetation found along the riverbanks of the Calyawan River in Barangay Andap, Municipality of New Bataan, Province of Davao de Oro, Philippines using the transect walk method. The goals were to determine the variety and abundance of the flora along the riverbank, evaluate the conservation status of the discovered plant species, and suggest measures for safeguarding and preserving the riparian environment. Study Design: The study employed a transect walk method to carry out an initial survey of the riparian vegetation. A 1-kilometer transect was conducted along the riverbanks of the Calyawan River to gather qualitative and quantiatative measurements of plant diversity. The evaluation took place on December 20, 2022. This approach facilitated a quick and systematic examination of the vegetation along the riverbanks. Place and Duration: The study was carried out on the riverbanks of the Calyawan River in Barangay Andap, Municipality of New Bataan, Province of Davao de Oro. The fieldwork was conducted on December 20, 2022. The region can be reached by using the Compostela-Montevista-Mati Boundary Road. Methodology: The transect walk approach was employed to record the riparian flora during the survey. Plant species were identified and photographed, but no tangible plant specimens were collected. The obtained data encompassed the identification of fern and angiosperm taxa and families encountered along the transect. The conservation status assessments were conducted using the pre-existing classifications of the species. Results: A rapid assessment revealed the presence of 49 distinct genera of ferns and angiosperm plants belonging to 30 different families along the transect. Out of these, 74% of the riparian plant genera that were identified were found to be endemic to the region. The assessment of the riparian plants' conservation status indicated that 37% were classed as vulnerable, 30% as least concern, 22% as other threatened species, 10% as endangered, and 1% were not categorized. Although the sample time was short, these findings emphasize the abundance and importance of the riparian flora in terms of conservation. Conclusion: The initial study conducted along the riverbanks of Calyawan River indicated a notable variety of plants that grow along the river, with a large number of species that are unique to that area. Many identified plants have a conservation status that emphasizes the necessity for heightened sampling efforts and monitoring in order to gain a more comprehensive understanding of and safeguard this rich ecosystem. Considering the clear human-induced stresses on the forest fragments in the region, it is advisable to enhance and broaden conservation efforts in order to protect the riparian vegetation and guarantee its ongoing existence.

4.
J Environ Biol ; 2024 Jul; 45(4): 408-417
Article | IMSEAR | ID: sea-238365

ABSTRACT

Aim: This research aimed to determine the distribution of different types of Urban green spaces (UGS) in Tbilisi districts, the distribution of access zones, the number of people who have access to UGSs, how current active housing construction affects UGSs and where reduction hotspots are located. Methodology: A 500-m buffer was set around UGSs. UGS changes were detected based on the NDVI from the 2017 and 2023 (June-August) PlanetScope imagery. The NDVI classification thresholds were -1 to 0.19 (nonvegetation), 0.19 to 0.5 (shrubs), and 0.5 or greater (trees). Thereafter, UGS patterns and reduction hotspots were determined in the district. Results: The percentage of access zones was lowest for Didube (5.4%) and highest for Nadzaladevi (14.7%). Chughureti (8.3%), Mtatsminda (8.8%), Isani (9.3%), and Gldani (9.9%) had similar numbers. The worst situation was observed in Samgori (8.9%) whereas the best situation was in Didube (69.8%). UGS degradation was high in Saburtalo (35.3%), and only a 0.6% decrease was found in Chughureti. Interpretation: UGSs are better distributed spatially and available to more people in "old" districts (Mtatsminda, Chughureti) and territories that were developed in the 1970s. The urban green spaces were neglected by contemporary urban sprawl. Though legislation has helped to preserve urban green spaces with status, but locations without status are victims of active development.

5.
Braz. j. biol ; 842024.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469269

ABSTRACT

Abstract The current focus is on the overall pattern of seed storage present in the fragments of the soil of piedmont and alluvial landscapes of the environment. The present study predicted the seed banks of both soils of alluvial and piedmont zones in different ecological conditions and evaluate the potential of seeds in the restoration of both environments. The composition of the seed bank of soil is mainly affected by the alluvial environment and the structure of cleared area shows that more species of germinating annual grasses and growable seeds with the higher total number. Extant vegetation structures have an important role in the diversity of soil seed reservoirs, whose composition corresponded with the openness of the site. When in situ soil seed bank is recruited, it helps to restore only some components of the plant community in an alluvial environment. In our current research, it was confirmed that seed richness was higher in number at lower elevation (alluvial) than that at high elevation (piedmont). Seed richness showed a significant negative correlation with anions, cations, while significantly positive with altitude that suggests the richness pattern of the overall seed bank of the area is influenced by various environmental factors.


Resumo O foco atual está no padrão geral de armazenamento de sementes presente nos fragmentos de solo do Piemonte e nas paisagens aluviais do meio ambiente. O presente estudo previu os bancos de sementes de ambos os solos das zonas aluvial e piemontesa em diferentes condições ecológicas e avaliou o potencial das sementes na restauração de ambos os ambientes. A composição do banco de sementes do solo é afetada principalmente pelo ambiente aluvial e a estrutura da área desmatada mostra que mais espécies de gramíneas anuais em germinação e sementes cultiváveis apresentam o maior número total. As estruturas da vegetação existente têm um papel importante na diversidade dos reservatórios de sementes do solo, cuja composição correspondeu à abertura do local. Quando o banco de sementes do solo in situ é recrutado, o mesmo ajuda a restaurar apenas alguns componentes da comunidade de plantas em um ambiente aluvial. Em nossa pesquisa atual, foi confirmado que a riqueza de sementes era maior em número em altitudes mais baixas (aluviais) do que em altitudes elevadas (Piemonte). A riqueza de sementes mostrou uma correlação negativa significativa com ânions, cátions, enquanto significativamente positiva com a altitude, o que sugere que o padrão de riqueza do banco geral de sementes da área é influenciado por vários fatores ambientais.

6.
Braz. j. biol ; 842024.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469386

ABSTRACT

Abstract The edge effect has impacts on seed and seedling survival due to modifications in biotic and abiotic factors. Often, large-seeded tree species lost seed vectors in the forest edge due to the rarity or absence of large frugivores at this habitat type. In this study, I compared the seedling abundance and distribution of the palm Syagrus flexuosa between edges and interiors of three large Cerrado remnants. In every remnant, the number of seedlings around parent palms in the edge was smaller than around palm individuals located in the Cerrado interior. Moreover, the distribution of seedlings around parent palms differed between edges and interiors. In the edges, most seedlings were found under parent crowns, while in the interiors, the contrary occurred. The high concentration of seedlings under parent palms suggests a decrease of seed dispersal at the edges. Because S. flexuosa is a widely distributed palm that serves as an important resource for several animals along Cerrado habitats, changes on the regeneration process of this palm due to edge effects can further impact frugivore populations. Therefore, the decline of seedling establishment along forest edges implies changes in the Cerrado regeneration dynamics, which may compromise the persistence of ecological processes and animal communities.


Resumo O efeito de borda tem impactos severos na sobrevivência de sementes e plântulas devido a modificações dos fatores bióticos e abióticos. Frequentemente, espécies arbóreas com sementes grandes perdem seus dispersores na borda da floresta devido à raridade ou ausência de grandes frugívoros neste tipo de habitat. Neste estudo, comparei a abundância e distribuição de plântulas de S. flexuosa entre bordas e interiores de três grandes remanescentes de Cerrado. Em cada remanescente, o número de plântulas ao redor das palmeiras-mãe, na borda, era menor do que ao redor dos indivíduos no interior do Cerrado. Nas bordas, a maioria das plântulas foi encontrada junto às plantas mãe, enquanto no interior ocorreu o contrário. A alta concentração de plântulas sob as plantas adultas sugere diminuição da dispersão de sementes nas bordas. Como S. flexuosa é uma palmeira amplamente distribuída que serve como um recurso importante para vários animais nos habitats do Cerrado, mudanças no processo de regeneração dessa palmeira devido aos efeitos de borda podem impactar ainda mais as populações de frugívoros. Portanto, o declínio do estabelecimento de plântulas ao longo das bordas do Cerrado implica em mudanças na dinâmica de regeneração do Cerrado, o que pode comprometer a persistência de processos ecológicos e comunidades animais.

7.
Braz. j. biol ; 84: e259137, 2024. graf
Article in English | LILACS, VETINDEX | ID: biblio-1364510

ABSTRACT

The edge effect has impacts on seed and seedling survival due to modifications in biotic and abiotic factors. Often, large-seeded tree species lost seed vectors in the forest edge due to the rarity or absence of large frugivores at this habitat type. In this study, I compared the seedling abundance and distribution of the palm Syagrus flexuosa between edges and interiors of three large Cerrado remnants. In every remnant, the number of seedlings around parent palms in the edge was smaller than around palm individuals located in the Cerrado interior. Moreover, the distribution of seedlings around parent palms differed between edges and interiors. In the edges, most seedlings were found under parent crowns, while in the interiors, the contrary occurred. The high concentration of seedlings under parent palms suggests a decrease of seed dispersal at the edges. Because S. flexuosa is a widely distributed palm that serves as an important resource for several animals along Cerrado habitats, changes on the regeneration process of this palm due to edge effects can further impact frugivore populations. Therefore, the decline of seedling establishment along forest edges implies changes in the Cerrado regeneration dynamics, which may compromise the persistence of ecological processes and animal communities.


O efeito de borda tem impactos severos na sobrevivência de sementes e plântulas devido a modificações dos fatores bióticos e abióticos. Frequentemente, espécies arbóreas com sementes grandes perdem seus dispersores na borda da floresta devido à raridade ou ausência de grandes frugívoros neste tipo de habitat. Neste estudo, comparei a abundância e distribuição de plântulas de S. flexuosa entre bordas e interiores de três grandes remanescentes de Cerrado. Em cada remanescente, o número de plântulas ao redor das palmeiras-mãe, na borda, era menor do que ao redor dos indivíduos no interior do Cerrado. Nas bordas, a maioria das plântulas foi encontrada junto às plantas mãe, enquanto no interior ocorreu o contrário. A alta concentração de plântulas sob as plantas adultas sugere diminuição da dispersão de sementes nas bordas. Como S. flexuosa é uma palmeira amplamente distribuída que serve como um recurso importante para vários animais nos habitats do Cerrado, mudanças no processo de regeneração dessa palmeira devido aos efeitos de borda podem impactar ainda mais as populações de frugívoros. Portanto, o declínio do estabelecimento de plântulas ao longo das bordas do Cerrado implica em mudanças na dinâmica de regeneração do Cerrado, o que pode comprometer a persistência de processos ecológicos e comunidades animais.


Subject(s)
Ecosystem , Arecaceae , Seedlings , Seed Dispersal
8.
Braz. j. biol ; 84: e255485, 2024. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1350312

ABSTRACT

Abstract The current focus is on the overall pattern of seed storage present in the fragments of the soil of piedmont and alluvial landscapes of the environment. The present study predicted the seed banks of both soils of alluvial and piedmont zones in different ecological conditions and evaluate the potential of seeds in the restoration of both environments. The composition of the seed bank of soil is mainly affected by the alluvial environment and the structure of cleared area shows that more species of germinating annual grasses and growable seeds with the higher total number. Extant vegetation structures have an important role in the diversity of soil seed reservoirs, whose composition corresponded with the openness of the site. When in situ soil seed bank is recruited, it helps to restore only some components of the plant community in an alluvial environment. In our current research, it was confirmed that seed richness was higher in number at lower elevation (alluvial) than that at high elevation (piedmont). Seed richness showed a significant negative correlation with anions, cations, while significantly positive with altitude that suggests the richness pattern of the overall seed bank of the area is influenced by various environmental factors.


Resumo O foco atual está no padrão geral de armazenamento de sementes presente nos fragmentos de solo do Piemonte e nas paisagens aluviais do meio ambiente. O presente estudo previu os bancos de sementes de ambos os solos das zonas aluvial e piemontesa em diferentes condições ecológicas e avaliou o potencial das sementes na restauração de ambos os ambientes. A composição do banco de sementes do solo é afetada principalmente pelo ambiente aluvial e a estrutura da área desmatada mostra que mais espécies de gramíneas anuais em germinação e sementes cultiváveis ​​apresentam o maior número total. As estruturas da vegetação existente têm um papel importante na diversidade dos reservatórios de sementes do solo, cuja composição correspondeu à abertura do local. Quando o banco de sementes do solo in situ é recrutado, o mesmo ajuda a restaurar apenas alguns componentes da comunidade de plantas em um ambiente aluvial. Em nossa pesquisa atual, foi confirmado que a riqueza de sementes era maior em número em altitudes mais baixas (aluviais) do que em altitudes elevadas (Piemonte). A riqueza de sementes mostrou uma correlação negativa significativa com ânions, cátions, enquanto significativamente positiva com a altitude, o que sugere que o padrão de riqueza do banco geral de sementes da área é influenciado por vários fatores ambientais.


Subject(s)
Soil , Seed Bank , Pakistan , Plants , Seeds , Ecosystem , Poaceae
9.
Rev. biol. trop ; Rev. biol. trop;71(1)dic. 2023.
Article in Spanish | SaludCR, LILACS | ID: biblio-1514955

ABSTRACT

Introducción: Las hormigas cumplen funciones ecológicas importantes en muchos ecosistemas, y son altamente sensibles a los cambios en el uso del suelo. Sin embargo, la respuesta ante estos cambios está poco documentada, a grandes escalas espaciales y en distintos usos de suelo, en ecosistemas poco estudiados como la Serranía del Perijá. Objetivo: Analizar la riqueza, diversidad y composición de las comunidades de hormigas en cuatro usos de suelo de dos paisajes agroforestales de la Serranía del Perijá, Cesar, Colombia. Métodos: En dos paisajes agroforestales (compensación y no compensación) se delimitaron dos ventanas de muestreo de 4 × 4 km. Dentro de cada ventana y paisaje se escogieron cuatro usos de suelo: bosques, sistemas agroforestales de café, regeneración natural y pastizales, en los cuales se aplicaron dos métodos de captura: trampas Pitfall y sacos Winkler. Se midieron seis variables ambientales: cobertura de dosel, altura de la hojarasca, densidad aparente, temperatura, humedad y dureza del suelo. El esfuerzo de muestreo fueron 384 trampas Pitfall y 192 m2 de extracción de hojarasca. El trabajo de campo se realizó entre febrero y marzo de 2021. Resultados: Las hormigas mostraron alta sensibilidad a los cambios en el uso del suelo. La diversidad y riqueza de especies disminuyó en los usos de suelo con menor cobertura vegetal natural, como los pastizales; mientras que los bosques, en ambos paisajes, conservaron la mayor riqueza de especies. La cobertura de dosel y la disponibilidad de hojarasca fueron los parámetros ambientales que favorecieron la diversidad y riqueza de las comunidades de hormigas en todos los usos de suelo. No se encontraron diferencias entre la composición de hormigas de los dos paisajes estudiados. Conclusiones: Las hormigas responden a los cambios de uso de suelo y en particular a la cobertura vegetal. Se confirmó nuestra hipótesis puesto que los usos de suelo con alta cobertura vegetal fueron los hábitats con mayor riqueza y diversidad de hormigas. La heterogeneidad ambiental, producto de la dinámica de transformación de los paisajes es un elemento que debe considerarse en futuras investigaciones.


Introduction: Ants fulfill important ecological functions in many ecosystems and are highly sensitive to changes in land use. However, the response to these changes is poorly documented, at large spatial scales and in different land uses, in poorly studied ecosystems such as the Serranía del Perijá. Objective: To analyze the richness, diversity, and composition of ant communities in four land uses of two agroforestry landscapes of the Serranía del Perijá, Cesar, Colombia. Methods: Two sampling windows of 4 × 4 km were delimited in two agroforestry landscapes (compensation and non-compensation). In each window and landscape four land uses were chosen: forests, coffee agroforestry systems, natural regeneration and pastures, in which two trapping methods were applied: Pitfall traps and Winkler bags. Six environmental variables were measured: canopy cover, leaf litter height, bulk density, temperature, humidity and soil hardness. The sampling effort was 384 Pitfall traps and 192 m2 of leaf litter extraction. The fieldwork was conducted between February and March 2021. Results: Ants showed high sensitivity to changes in land use. Species diversity and richness decreased in land uses with less natural vegetation cover, such as pastures; while forests, in both landscapes, retained the highest species richness. Canopy cover and leaf litter availability were the environmental parameters that favored the diversity and richness of ant communities in all land uses. No differences were found between the ant composition of the two landscapes studied. Conclusions: Ants respond to changes in land use, particularly to vegetation cover. Our hypothesis was confirmed since land uses with high vegetation cover were the habitats with the greatest richness and diversity of ants. Environmental heterogeneity, a product of the dynamics of landscape transformation, is an element that should be considered in future research.


Subject(s)
Animals , Ants/classification , Colombia
10.
Rev. biol. trop ; Rev. biol. trop;71(1)dic. 2023.
Article in Spanish | LILACS, SaludCR | ID: biblio-1514954

ABSTRACT

Introducción: Las comunidades de macroinvertebrados son afectadas simultáneamente por la calidad del agua y las características físicas del hábitat acuático, complicando su uso en la bioindicación. Objetivo: Determinar cuáles variables del hábitat condicionan la comunidad de macroinvertebrados acuáticos en algunas corrientes (quebradas) de montaña del Oriente antioqueño (Colombia). Métodos: El muestreo se realizó en febrero 2021 (periodo de transición seco-lluvia), para evaluar variables físicas y químicas en tres tipos de mesohábitats: rápidos, rizos y pozas en corrientes con coberturas vegetales contrastantes. Los macroinvertebrados fueron recolectados en diez sitios de muestreo con red tipo net, pantalla y manual, y preservados en etanol al 70 %. Resultados: Se recolectaron 4 484 macroinvertebrados (16 órdenes, 46 familias y 75 géneros). El mesohábitat rizo presentó mayores valores de diversidad y abundancia, mientras las pozas presentaron los menores. Hubo diferencias en la concentración de oxígeno, profundidad, velocidad y abundancia de macroinvertebrados entre mesohábitats. Las pozas defirieron de los otros mesohábitats en profundidad, velocidad, así como en la composición, abundancia y riqueza de macroinvertebrados, y fue el hábitat de menor preferencia. Conclusión: La velocidad, profundidad y concentración de oxígeno disuelto, desempeñan un papel muy importante en el establecimiento de las comunidades de macroinvertebrados en los diferentes mesohábitats. En el mismo tipo de mesohábitat, la calidad de la cobertura vegetal determinó la diversidad y abundancia de esta comunidad.


Introduction: Macroinvertebrate communities are affected by water quality and physical characteristics of the aquatic habitat, simultaneously, complicating their use as bioindicators. Objective: To determine which habitat variables regulate the macroinvertebrate community in mountain streams in Eastern of Antioquia (Colombia). Methods: Sampling was carried out in February 2021 (dry-rain transition period), to evaluate physical and chemical variables in three types of mesohabitat: ripples, pools, and rapids in streams with contrasting vegetation covers. The macroinvertebrates were collected from ten sampling sites with a net, screen and manual type net preserved with 70 % ethanol. Results: 4 484 macroinvertebrates were collected (16 orders, 46 families and 75 genera). The ripples mesohabitat presented higher values of diversity and abundance, while the pools presented the lowest. There were differences for oxygen concentration, depth, speed, and macroinvertebrate abundance between mesohabitats. Pools differed from the other mesohabitats in depth, speed, as well as in composition, abundance, and richness in macroinvertebrates, and was the least preferred mesohabitat. Conclusion: Speed, depth, dissolved oxygen concentration played a very important role in the establishment of macroinvertebrates community in different mesohabitats. For the same type of mesohabitat, the quality of the plant cover determined both diversity and abundance of this community.


Subject(s)
Animals , Rivers , Invertebrates/anatomy & histology , River Pollution , Colombia
11.
CienciaUAT ; 18(1): 6-24, jul.-dic. 2023. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1513968

ABSTRACT

RESUMEN El Bosque Mesófilo de Montaña (BMM) del centro de Veracruz, México, representa un paisaje alterado por actividades antrópicas, por lo que es necesario evaluar el potencial evolutivo y adaptativo de las aves refugiadas en el sitio, las cuales se enfrentan a un paisaje con un gradiente heterogéneo. El objetivo de este estudio fue determinar la diversidad de aves en fragmentos de BMM y vegetación secundaria (VS), en el predio Finca La Pastoría, Huatusco, Veracruz, así como, asociar su presencia y/o alimentación a cada hábitat evaluado. Se identificaron las especies y número de individuos en 14 sitios de observación de aves, con el método de muestreo basado en conteo por puntos con radio fijo de 30 m. Se registraron 100 especies pertenecientes a 33 familias y 15 órdenes. En el BMM se identificaron 916 individuos, correspondientes a 89 especies, y en VS 331 individuos de 54 especies, encontrando diferencias significativas de diversidad de aves entre coberturas de muestreo. Destacan los registros de Dendrortyx barbatus, Leptotila verreauxi y Vireo griseus, por ser endémicas. La primera está clasificada en peligro de extinción, mientras que la segunda se encuentra sujeta a protección especial y la tercera amenazada. También se registraron Pionus senilis, especie amenazada; Falco peregrinus, Micrastur semitorquatus, Passerina ciris, Psarocolius montezuma, Myadestes occidentalis y Amazona albifrons, sujetas a protección especial. Este estudio brinda información sobre cómo la avifauna hace uso diferencial de dos coberturas de vegetación, la cual puede servir para generar estrategias sustentables para el manejo y conservación del bosque.


ABSTRACT The Cloud Forest (CF) in central Veracruz, Mexico, represents a landscape that has been altered by anthropic activities. Therefore, it is necessary to evaluate the evolutionary and adaptive potential of the birds sheltered in the site, which face a landscape with a heterogeneous gradient. The objective of the study was to describe the diversity of birds in fragments of CF and secondary vegetation (VS), in the property "Finca La Pastoría", Huatusco, Veracruz. The species and number of individuals in 14 bird watching sites were identified, with the sampling method based on counting points with a fixed radius of 30 m. 100 species from 33 families and 15 orders were recorded. In the CF, 916 individuals were identified, corresponding to 89 species, and in VS 331 individuals of 54 species, finding significant differences in bird diversity between sampling coverages. The records of Dendrortyx barbatus, Leptotila verreauxi and Vireo griseus stand out for being endemic and classified as endangered and threatened, respectively. Furthermore, Pionus senilis, a threatened species, as well as Falco peregrinus, Micrastur semitorquatus, Passerina ciris, Psarocolius montezuma, Myadestes occidentalis and Amazona albifrons, subject to special protection, were also recorded. This study provides information on how the birds make differential use of two vegetation covers, which can be used to generate sustainable strategies for forest management and conservation.

12.
Article | IMSEAR | ID: sea-230666

ABSTRACT

Forests play a critical role in combating climate change and promoting sustainable development. They are often referred to as the "lungs of the Earth" because they absorb carbon dioxide and release oxygen, making them vital for regulating the planet's climate and supporting life. Forests act as carbon sinks, absorbing and storing significant amounts of carbon dioxide from the atmosphere. Trees, through the process of photosynthesis, convert carbon dioxide into organic matter, which is stored in their biomass and in the soil. This process helps reduce the concentration of greenhouse gases, mitigating climate change. Forests are home to a vast array of plant and animal species. Biodiversity is essential for the stability and resilience of ecosystems. Maintaining healthy and diverse forests helps ensure that ecosystems can adapt to changing environmental conditions and continue to provide ecosystem services that support sustainable development. Forests contribute to climate regulation by influencing temperature, precipitation, and weather patterns. They release water vapor into the atmosphere through a process known as transpiration, which can lead to increased cloud cover and precipitation, thus affecting local and regional climates. Forests play a crucial role in protecting watersheds and maintaining the quality and availability of freshwater resources. Tree roots stabilize soil, reducing erosion and maintaining water quality. Forested areas often act as natural filters, removing pollutants and sediments from runoff. Forests provide livelihoods for millions of people worldwide, especially in rural areas. Sustainable forest management practices can ensure a steady supply of timber, non-timber forest products, and ecosystem services, contributing to the economic well-being of local communities. Forests offer various ecosystem services, including regulating services (climate regulation, water purification, erosion control), provisioning services (timber, fuelwood, non-timber forest products), cultural services (recreation, spiritual value), and supporting services (nutrient cycling, pollination). Adopting sustainable forest management practices is crucial to maintaining the benefits provided by forests. Sustainable logging, afforestation, and reforestation efforts can help maintain and even enhance the carbon sequestration capacity of forests. Recognizing and respecting the rights of indigenous peoples in forest management is essential. Indigenous communities often have valuable traditional knowledge of sustainable forest practices and can play a key role in conservation and sustainable development efforts. Efforts to restore degraded forests and establish new forested areas (reforestation and afforestation) can contribute to climate change mitigation and the protection of biodiversity. Global agreements such as the Paris Agreement and the United Nations Sustainable Development Goals (SDGs) acknowledge the importance of forests in climate action and sustainable development, providing a framework for global cooperation. In conclusion, forests are integral to addressing climate change and promoting sustainable development. Efforts to conserve and sustainably manage forests are essential to achieving environmental, social, and economic goals at both local and global levels. Recognizing the multifaceted benefits of forests and integrating them into climate and development strategies is crucial for a more sustainable and resilient future.

13.
Article | IMSEAR | ID: sea-230566

ABSTRACT

Aim: This study was taken up to investigate the usefulness of Remote Sensing & GIS tools for the evaluation of fourteen watershed projects implemented under Pradhan Mantri Krishi Sinchayee Yojana (PMKSY) project in East Godavari District of Andhra Pradesh.Place and Duration of Study: This study was conducted by Panchayat Raj and Rural Development Department, Andhra Pradesh 2009 to 2022.Methodology: High-resolution data like Resourcesat-2, Linear Imaging and Self Scanning-IV (LISS-IV) of 2011 (pre-treatment) and 2016 (post-treatment) were used in this project to measure the changes in land use/land cover and biomass during the project period (2011-16). Due to the implementation of the watershed developmental activities, an additional area of 11417 ha has been brought under cultivation.Results: The fallow land area decreased by 3686.12 Ha (24.12%) which is attributed to dense and open vegetation categories. The output of the Normalized Difference Vegetation Index classification indicates the increase in dense vegetation by 9804.05 ha, which indicates there is an improvement in the open vegetation category due to the reclamation of fallow land.Conclusion: This study reveals that an additional area of 126.88 ha (12.80%) increased under water bodies and 3686.12 ha wasteland converted to cultivable land due to the construction of farm ponds, percolation tanks and check dams. This area is attributed to cropland and plantations.

14.
Article | IMSEAR | ID: sea-230463

ABSTRACT

Food and fibre, two of humanity's most fundamental requirements, are met by agriculture. In the last century, new farming methods have been introduced, such as the Green Revolution, which has enabled agriculture to keep up with the increasing demand for food and other agricultural goods. But population growth, rising income levels, and increased food demand will probably put more stress on the planet's natural resources. As the detrimental effects of agriculture on the environment become more widely acknowledged, new methods and strategies need to be able to meet future food needs while preserving or lessening the environmental footprint of agriculture. Informed management decisions aiming at increasing crop production could be made with the help of emerging technologies like artificial intelligence (AI), Internet of Things (IoT), big data analysis, and geospatial technology. Many scientists, engineers, agronomists, and researchers use a variety of technologies each year to boost agricultural output while minimising pollution, yet these efforts have a negative environmental impact. Precision agriculture examines how technology might be applied to enhance agricultural practises relative to traditional methods while minimising negative environmental effects. Precision agriculture greatly benefits from the deployment of remote sensing technologies, which also presents new chances to enhance agricultural practises. Geographically, latitude and longitude data can be recorded for field data (slope, aspect, nutrients, and yield) using the global positioning system (GPS). Because of its ability to continuously determine and record the right position, it can build a larger database for the user. Geographic Information Systems (GIS), which can handle and store these data, are needed for the additional analysis. This review will offer you an overview of Remote Sensing technology, GPS, and GIS, and how it might be used for precision agriculture.

15.
Article | IMSEAR | ID: sea-227478

ABSTRACT

Background: This study aimed to assess the effect of enhanced vegetation index, proximity to national borders, proximity to protected areas, and water on malaria morbidity in Sub-Saharan Africa. Methods: Data were pooled from the Demographic and Health Surveys (DHS) conducted in 32 Sub-Saharan African countries spanning 2000 to 2020. Women's standard weights were denormalized and bivariate analyses were conducted to identify potential confounders. Two models were fitted; model 1 involved primary exposure variables and model 2 involved primary exposure variables adjusted for significant confounders. The final interpretation of the results was based on model 2. Results: The prevalence of malaria cases was 23.1%, The risk of children suffering malaria in households that belong to the 3rd quantile of the vegetation index is 27% less compared to children that belong to the households in the 1st quantile of the vegetation index [aOR=0.73, 95%CI: 0.55-0.99; p-value<0.05]. Children belonging to households in the 4th quantile of proximity to water have a 33% higher risk of suffering from malaria compared to households that are closer to water [aOR=1.33, 95%CI:1.08-1.63; p-value<0.01]. Conclusions: Environmental factors have been found to influence malaria morbidity among children in SSA. Intervention should be targeted at households especially those that are closer to water with more children under five to ensure full access and use of ITNs among all children under five as part of the overall goal of achieving the health-related SDGs.

16.
Article | IMSEAR | ID: sea-229291

ABSTRACT

Remote sensing technology has revolutionized agriculture management and monitoring by providing valuable information on crop health, soil conditions, weather patterns, and overall land management. The reflectance data are progressively being exploited in agriculture with the momenta gained in ground-based, airborne, and satellite remote sensing. The agriculture systems when managed conventionally don’t facilitate the proper utilization of resources and productivity potential of the soil. However, taking the aid of remote sensing techniques helps in boosting the productivity potential of the soil and optimizing the inputs. This paper aims to review the potential applications of remote sensing in agriculture and its role in improving productivity, resource efficiency, and sustainability. The paper discusses various remote sensing techniques, including satellite imagery, aerial photography, and sensor-based data collection, and their integration with advanced data analysis methods. The applications explored include biomass estimation, yield estimation, global food demand, salinity stress detection, drought monitoring, soil moisture content assessment, and change detection. The paper highlights the benefits and challenges associated with each application and provides insights into future research directions and technology advancements in the field of remote sensing for agriculture.

17.
Acta biol. colomb ; 28(2): 328-332, mayo-ago. 2023. tab
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1573626

ABSTRACT

RESUMEN El conocimiento de la biodiversidad acuática de ecosistemas lénticos es escaso en muchas regiones del mundo. Por ello, se consideró importante realizar evaluaciones preliminares de la fauna bentónica de poca profundidad en tres franjas subacuáticas de muestreo entre los 0 a 10 m en una zona rocosa del área noreste del lago de Coatepeque, El Salvador. Las familias más abundantes fueron Thiaridae (Gastropoda), Hyalellidae (Malacostraca, Amphipoda) y larvas de Coenagrionidae (Insecta, Odonata) entre la orilla y 2,5 m de profundidad. En los sedimentos finos (10 m) se encontró una riqueza de especies y abundancia reducida en comparación a los estratos menos profundos, así como una gran cantidad de conchas vacías de caracoles de la familia Thiaridae y cápsulas cefálicas de larvas de quironómidos (Insecta, Diptera).


ABSTRACT The knowledge of aquatic biodiversity in lentic ecosystems is scarce in many regions of the world. Therefore, it was considered important to accomplish preliminary assessments of benthic fauna associated with low depths in three sampling subaquatic fringes between 0 and 10 m on a rocky shore along the northeast area of Coatepeque Lake, El Salvador. The most abundant families were Thiaridae (Gastropoda), Hyalellidae (Malacostraca, Amphipoda), and Coenagrionidae (Insecta, Odonata) from the edge to a depth of 2,5 m. A reduced species richness and abundance were found in fine sediments (10 m) in comparison to shallower strata, as well as a lot of empty shells of the Thiaridae family and cephalic capsules of chironomid larvae (Insecta, Diptera).

18.
Article | IMSEAR | ID: sea-229050

ABSTRACT

The assessment and analysis of Land Use/Land Cover (LULC) changes are required to identify the land use changes from year to year which plays a critical role in planning and implementation of developmental activities. The present study aims to assess LULC changes in Samastipur district of Bihar using Remote Sensing (RS) and Geographical Information System (GIS). The LULC maps were prepared using LANDSAT-5 and LANDSAT-8 images by adopting object based image classification technique. Assessments of LULC changes were done @ 5 years, @ 10 years and @ 20 years during 2000-2020. The results indicated that the agriculture land coverage increased at high rate during 2000-2005 and 2005-2010; and after that it is increasing at slow rate. The natural vegetation coverage is continuously decreasing during years 2000-2020 while settlement is continuously increasing during this period with notable increase during 2000-2005 and 2015-2020. In the time interval of 10 years (2000-2010), the agriculture land area increased by 22.17%; natural vegetation area decreased by 38.04%; the water-bodies decreased by 46.69%; sand and barren land decreased by 61.27% and settlement area increased by 15.62%. Over the next 10 years (2010-2020), area covered by agriculture land, settlement, water-bodies and sand and barren land increased by 8.05%, 38.30%, 26.27% and 44.65% respectively while area covered by natural vegetation decreased by 75.24%. During time interval of 20 years (2000-2020), agriculture land area and settlement area increased by 32% and 59.91% respectively while natural vegetation, sand and barren land and water-bodies decreased by 84.66%, 43.98% and 32.68% respectively. The analysis of the results indicates that the natural vegetation has decreased at fast rate in the recent years. Therefore, proper attention is required towards stopping of cutting of natural vegetation in the district to save the environment.

19.
Article | IMSEAR | ID: sea-220325

ABSTRACT

Introduction: Infective Endocarditis (IE) is a serious disease whose prognosis depends on early management. Aortic localization is characterized by its progression to myocardial failure and the high number of complications motivating early recourse to surgery. The diagnosis of AR is based on microbiological and imaging studies. Echocardiography is the recommended imaging modality to make the diagnosis, assess the impact and guide surgery. Materials and Methods: This is a retrospective study, including all subjects over 20 years of age who presented with infective endocarditis of the aortic valve, hospitalized between January 2019 and December 2022, in the Department of Cardiology and Vascular Diseases at the ERRAZI-CHU Mohammed VI Hospital in Marrakech. Clinical, paraclinical and therapeutic data were collected for each case using an exploitation form. Results: During the study period, 26 patients had presented with aortic positional AR, with a sex ratio that was equal to 1.8. The mean age of the patients was 43±12.5 years. A known history of valvular disease was found in 57% of the cases. Among the native valvular diseases, rheumatic origin was found in 85%. The most common valvular lesions were represented by vegetations (88%), which were mobile in 56%, measuring between 10 and 20 mm in half of the cases, their most predominant localization was on the ventricular side with a tilt.IE on severe IAo was found in 90% of cases. The most common associated valvulopathies were MI (53%), RAo (38%) and MR (34%), whose severity was variable. The association of aortic disease with mitral disease was the most frequent association. Echocardiographic complications were presented by fistulas, perforations and peri-aortic abscesses (2 cases each) which were correlated with severe AI. Regarding the impact of the aortic AR on the LV, we noted a marked dilatation in 42% of cases with a preserved ejection fraction in 74%. A quarter of our patients had undergone transesophageal echocardiography in addition to transthoracic echocardiography, with an average time between admission and completion of 3 days. The indication of its realization was posed in front of the doubt of the visualization of an image of vegetations or suspicion of complications not visualized with the TTE. Valvular lesions found on TEE were essentially vegetations in 45% of cases, prolapses in 22% of cases, as well as abscesses, para-prosthetic leaks and prosthesis deinsertion found in 11% of cases. Conclusion: Aortic AR remains a frequent pathology in our context. Aortic insufficiency is the most predisposing valvulopathy and the most common sonographic appearance is vegetations. The results of our study have shown that complications of AE occur preferentially in patients with severe aortic insufficiency.

20.
J Environ Biol ; 2023 May; 44(3): 335-344
Article | IMSEAR | ID: sea-238414

ABSTRACT

Aim: The main objective of the present study is to quantify and assess the changes in vegetation cover by using NDVI values from the Kannad Taluka of Aurangabad district, Maharashtra, India. The changes were studied during the period 2013 to 2020 to identify the probable causes of change in NDVI. Methodology: The present study utilized Landsat images to evaluate and track the changes in vegetation cover by using the NDVI index values and classified in eight classes during seven years period. Results: Two of the major NDVI classifications of this area were agriculture and urban area which showed a significant decrease in the year 2020 while in the water bodies, dense forest, sparse forest, grass land mixed with shrubs, grass land and barren land were increased. Area covered by agriculture and urban area was found 36.40% and 4.47 % in 2013 and which was noted to reduce by 21.64% and 2.53 % in 2020. The water bodies, dense forest, sparse forest, grass land and shrubs, grass land and barren land were found to be 1.79%, 6.18%, 9.71%, 12.71%, 12.92%, and 15.82 % in the year 2013 and were increased up to 2.17%, 14.28%, 13.52%, 13.49%, 14.54% and 17.83 % in 2020, respectively. Interpretation: Area covered by agriculture has decreased by 14.76% in seven year period while the barren land increased by 2.01% in seven year period in Kannad Taluka. The loss of forest cover might be due to increased human population in the study area.

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