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1.
Neotrop. ichthyol ; 19(3): e210034, 2021. graf, mapas, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1340234

ABSTRACT

Our objective was to evaluate the effectiveness of protected areas (PAs) in the Paraná-Paraguay basin on multiple facets of ichthyofauna, both currently and in future climate change scenarios, based on reaching the 17% of conserved terrestrial and inland water defined by Aichi Target 11. Analyses were carried out vis-à-vis a distribution of 496 native species, modeling for the present and for the future, and in moderate and pessimistic scenarios of greenhouse gases. We calculated species richness, functional richness, and phylogenetic diversity, overlapping the combination of these facets with the PAs. The results indicate that the current PAs of the Paraná-Paraguay basin are not efficient in protecting the richest areas of ichthyofauna in their multiple facets. While there is a larger overlap between PAs and the richest areas in phylogenetic diversity, the values are too low (2.37%). Currently, the overlap between PAs and areas with larger species richness, functional richness, and phylogenetic diversity is only 1.48%. Although this value can increase for future projections, the values of the indices decrease substantially. The relevant aquatic environments, biological communities, and climate change should be considered as part of the systematic planning of PAs that take into consideration the terrestrial environments and their threats.(AU)


Nosso objetivo foi avaliar a efetividade das áreas protegidas da bacia Paraná-Paraguai sobre múltiplas facetas da ictiofauna, atualmente e em cenários futuros de mudanças climáticas baseado em alcançar 17% de áreas protegidas, de acordo com os objetivos de Aichi. Análises foram feitas a partir da distribuição de 496 espécies para o presente e futuro, em diferentes cenários climáticos. Foram calculadas a riqueza de espécies, a riqueza funcional e a diversidade filogenética, sobrepondo a combinação destas facetas com as áreas protegidas. Os resultados indicaram que as áreas protegidas da bacia Paraná-Paraguai não são eficientes em proteger as áreas mais ricas em ictiofauna considerando diversas facetas. A maior sobreposição se dá entre as áreas protegidas e as áreas mais ricas em diversidade filogenética, mas os valores são muito baixos (2,37%). A sobreposição entre as áreas protegidas e os 17% das áreas com maior riqueza de espécies, riqueza funcional e diversidade filogenética é de apenas 1,48%. Para o futuro as projeções indicaram que a sobreposição pode aumentar, mas os valores dos índices caem consideravelmente. Os ambientes aquáticos e as mudanças climáticas são componentes que devem ser considerados no planejamento sistemático de áreas protegidas que consideram essencialmente ambientes terrestres e suas ameaças.(AU)


Subject(s)
Animals , Climate Change , Protected Areas/analysis , Fishes , Phylogeny , Genetic Variation
2.
Acta sci., Biol. sci ; 42: e49958, fev. 2020. map, tab, ilus, graf
Article in English | LILACS, VETINDEX | ID: biblio-1460952

ABSTRACT

Less than 10% of the original Atlantic Forest cover now remains standing in the Brazilian state of Sergipe, although few scientific studies have focused on its mammalian diversity. The present study describes the diversity of non-volant mammals found in the Ibura National Forest (INF), based on live trapping, and direct and indirect observations. We sampled the IBF on six days per month between June 2012 and August 2013, using live-traps (Sherman-type) positioned in pairs (ground and understory). We equally sampled semideciduous forest and an abandoned Eucalyptusplantation with dense understory (over 30 years). We also used non-systematics methods (direct observations, vestiges, camera-trap, and opportunistic captures). We recorded 18 species, from 12 families and 7 orders considering all the applied methods. Among recorded species, Bradypus torquatusand Lontra longicaudisare considered threatened of extinction. Considering only the live-trapping (totaling 3,240 trapping nights), we captured 125 individuals (3.85% success) from four species, Marmosa demerarae(52%), Didelphis albiventris(19.2%), Cerradomys vivoi(15.2%), and M. murina(13.6%). Estimated and observed richness was the same, suggesting a satisfactory effort. Didelphis albiventrisand M. demeraraeshowed significantly higher captures in the dry seasons. Didelphis albiventrisand C.vivoishowed significantly higher captures in the substratum, and M. demeraraehigher in the understory. Cerradomysvivoishowed significantly higher captures in the Eucalyptusphytophysiognomy. Non-Metric Multidimensional Scaling and the ANOSIM showed a significant difference in the captured species among semidecidual forest and Eucalyptus. Despite the small area (144 ha), the INF still houses a relatively high mammalian diversity. Further investigations may help to understand the role of habitat reduction in the diversity and habitat partitioning among mammal species in the Atlantic Forest of Northeastern Brazil.


Subject(s)
Animals , Biodiversity , Ecosystem , Mammals/anatomy & histology , Protected Areas/analysis
3.
Rev. biol. trop ; 66(2): 863-879, abr.-jun. 2018. tab, graf
Article in Spanish | LILACS, SaludCR | ID: biblio-977351

ABSTRACT

Resumen La Selva Baja Caducifolia (SBC) es de gran importancia por su biodiversidad. En el Istmo-Costa de Oaxaca, México, se encuentran áreas con SBC y distinta categoría de protección (legislación mexicana): (1) Área Natural Protegida (ANP), (2) Área Destinada Voluntariamente para la Conservación (ADVC) y (3) Área de Uso Común (ADUC). En cada una de ellas se analizó la estructura de vegetación leñosa, plantas con DAP ≥ 2.5 cm, muestreando 15 parcelas de 100 m2. La riqueza observada fue de 90 especies incluidas en 36 familias y corresponde al 80 % (Jackknife) y 85 % (ICE) de la esperada. El análisis de agrupamiento identificó dos grupos con 90 % de disimilitud: el primero (G1) incluyó a todas las parcelas muestreadas del ANP; y el segundo (G2) aglomeró las del ADVC y ADUC. Los índices de Shannon, dominancia de Simpson y diversidad verdadera de Jost para el G1 fueron H'= 2.43, D= 0.21 y qD= 11 y para el G2, H'= 2.76, D= 0.28 y qD= 15, sin diferencias entre grupos (P < 0.05). Las especies con Valor de Importancia Relativa más elevado, en ambos grupos, corresponden a vegetación secundaria. La densidad de especies del G1 fue de 1 829 ind/ha y en el G2 de 2 370 ind/ha. Los promedios de altura (6.8 m) y área basal (19.7 m2/ha) del G1 no variaron significativamente (P < 0.05) con los del G2 (7.9 m y 22.1 m2/ha). Las ADVC y ADUC, semejantes en composición y estructura, difieren del ANP. Se sugiere seguir monitoreando la SBC.


Abstract Tropical dry forest (TDF) is important due to its biodiversity. In the Isthmus-Coastal region of the state of Oaxaca, in Southeast Mexico, there are many areas of TDF with varying categories of legal protection (1) Protected Natural Areas (PNA), (2) Voluntarily Designated Conservation Areas (VDCA) and (3) Areas of Common Use (ACU). In each of these, tree vegetation structure was analysed, recording plants with a DBH ≥ 2.5 cm and sampling 15 plots of 100 m2. Observed richness was 90 species, belonging to 36 families and corresponding to 80 % (Jackknife) and 85 % (ICE) of expected richness. A cluster analysis identified two groups with 90 % dissimilitude: the first (G1) included all the sampled plots in the PNA; and the second (G2), grouped together those from the VDCA and the ACU. The Shannon, Simpson dominance and Jost true diversity indices for G1 were H'= 2.43, D= 0.21 and qD= 11 and for G2, H'= 2.76, D= 0.28 and qD= 15 respectively, with no differences between groups (P < 0.05). The species that presented the highest relative importance value (RIV) in both groups, corresponded to secondary vegetation. Species density of G1 was 1 829 ind/ha and 2 370 ind/ha for G2. Mean height (6.8 m) and basal area (19.7 m2/ha) of G1 did not vary significantly (P < 0.05) when compared to G2 (7.9 m y 22.1 m2/ha). The VDCA and ACU presented similar composition and structure, differing from the PNA. Continual monitoring of the TDF is suggested. Rev. Biol. Trop. 66(2): 863-879. Epub 2018 June 01.


Subject(s)
Soil , Trees/classification , Forestry/classification , Endangered Species/statistics & numerical data , Conservation of Natural Resources/statistics & numerical data , Protected Areas/analysis , Ecological and Environmental Phenomena , Mexico
4.
Rev. biol. trop ; 62(supl.1): 65-83, feb. 2014. graf, mapas, tab
Article in English | LILACS, SaludCR | ID: lil-753724

ABSTRACT

Tropical Eastern Pacific island streams (TEPis) differ from other neotropical streams in their rainy climate, mixed sedimentary-volcanic geology and faunal composition. Yet, their relationships between environmental characteristics and stream biota remain unexplored. We analyzed the environmental subject at three spatial scales using a fully nested sampling design (6 streams, 2 reaches within each stream, 2 habitats within each reach, and 4 replicates per habitat) on Gorgona Island (Colombia). Sampling was carried out in two months with contrasting rainfall during early 2009. We studied the spatial variation of assemblage composition and density along with 27 independent variables within two contrasting rainfall conditions. Five stream-scale variables, two reach-scale variables, and five habitat-scale variables were selected using a Canonical Correspondence Analysis (CCA). A partial CCA showed that the total variance explained was 13.98%, while stream- and habitat-scale variables explained the highest proportion of the variance (5.74 and 5.01%, respectively). Dissolved oxygen (as affected by rainfall), high-density use zone (a management category), and sedimentary geology were the best descriptors of insect assemblages. The two latter descriptors affected fine-scale variables such as total benthic organic matter and gravel substratum, respectively. A Nested ANOVA showed significant differences in total density and richness among streams and habitats, and significant differences between the two sampling months regardless of the spatial scale. The evenness showed a significant stream- and habitat-dependent temporal variability. These results suggested that rainfall regime in Gorgona Island might be a driver of insect assemblage dynamics mediated by water chemistry and substratum properties. Spatial assemblage variability here is greater within habitats (among samples), and a minor fraction occurs at habitat- and stream-scales, while no longitudinal pattern was observed probably due to the short courses. Temporal variability should be further studied relative to rainfall and discharge regimes. Rev. Biol. Trop. 62 (Suppl. 1): 65-83. Epub 2014 February 01.


Las quebradas insulares del Pacífico Tropical Oriental difieren de otras quebradas neotropicales en términos de regímenes de lluvia, geología sedimentaria-volcánica, y composición faunística; pero la relación entre características ambientales y la biota de estas quebradas insulares permanece inexplorada. En este estudio, conducido en Isla Gorgona, se analizó el efecto restrictivo de 27 variables ambientales sobre la distribución, composición y densidad de los insectos acuáticos en tres escalas espaciales; se consideraron además diferencias en las intensidades de la lluvia entre los muestreos. Los muestreos se realizaron en 2009, en dos meses con intensidades de lluvia contrastantes; se siguió un diseño muestral anidado (6 quebradas, 2 tramos en cada quebrada, 2 hábitats en cada tramo, y 4 réplicas por hábitat). En un ACC fueron seleccionadas 5 variables operando a la escala-quebrada, 2 a la escala-tamo y 5 a la escala-hábitat. Un ACC parcial mostró que la varianza total explicada fue de 13.98%; las variables de las escalas hábitat y quebrada explicaron la mayor proporción (5.74 y 5.01%, respectivamente). Los mejores descriptores del “ensamblaje” fueron, oxígeno disuelto (influenciado por la lluvia), zona de alta densidad de uso y geología sedimentaria. Las dos últimas afectaron variables de escalas menores tales como, materia orgánica béntica y sustrato de gravas. Un ANOVA anidado presentó diferencias significativas de densidad total y de riqueza entre quebradas y hábitats, así como entre meses. La equidad mostró una variabilidad temporal significante dependiente de la quebrada y del hábitat. Se sugiere que el régimen de lluvia podría ser el conductor principal de las dinámicas, pues influye en la química del agua y en las propiedades de los sustratos. La variabilidad espacial de la composición y la estructura es mayor dentro de los hábitats (entre las muestras), y en menor proporción en las escalas quebrada y hábitat. No se definió un patrón longitudinal debido probablemente a la corta longitud de las quebradas. La variabilidad temporal debe ser estudiada a fondo en función de los regímenes de lluvia y de descarga.


Subject(s)
Marine Currents/analysis , Benthic Fauna/analysis , Protected Areas/analysis , Colombia , Rivers
5.
Rev. biol. trop ; 60(supl.1): 127-137, Mar. 2012. graf, tab
Article in English | LILACS, SaludCR | ID: lil-657859

ABSTRACT

The Inlet of Xel-Ha is used as a park for ecotourism, representing a sanctuary for the conservation of Pink Queen Conch. Increasing fishing pressure has led to the inclusion of the species in CITES. Most knowledge about the growth of the queen conch was generated through aquaculture, ocean enclosures or obtained using estimates derived from population dynamics. In this study we estimated the growth rate of juvenile S. gigas in a natural protected area by direct methods, during the period of April 2009 to January 2011. Data was obtained by capture-mark-recapture sampling. 1418 individuals were tagged and growth of 714 conchs was analyzed. Population size and density was estimated using Schnabel’s method. The average density was estimated at 0.1694 ± 0.0996ind. m-2, while the highest density was estimated for September 2010 (0.3074ind. m-2). The highest growth rate (0.27 ± 0.10mm day-1) was detected in juveniles with an initial size between 100-149mm, followed by conch <100mm, with an increase of 0.24 ± 0.05mm day-1. The growth rate decreased for individuals with an initial size between 150-199mm (0.18 ± 0.09mm day-1) and for organisms > 200mm (0.08 ± 0.07mm day-1). Variability in growth rate was high in conch 100-149mm and showed seasonal differences, with the highest growth rate in May 2010. Recruitment of juveniles was highest in October 2009 and February 2010. The population of Xel-Ha has grown in size and more large and juvenile conch could be found than in previous studies, indicating that Xel-ha park is working as a sanctuary for the conservation of the queen conch in Mexico’s Riviera Maya. The growth rate of juvenile conch in Xel-Ha is high and exhibits large variations in individuals, reflecting the natural conditions of foraging and aggregation. Seasonal differences in growth rate may be associated with water quality and availability of nutrients for primary production. We conclude that the direct method is useful for the assessment of growth in juvenile S. gigas and that growth in natural conditions may be higher than in aquaculture systems. This information may be applied to fishery management as well as rehabilitation programs and aquaculture.


La Ensenada de Xel-Ha es usada como parque para ecoturismo y representa un santuario para la conservación del caracol rosado. El incremento en la presión de la pesca ha llevado a la inclusión de esta especie en CITES. Mucho del conocimiento acerca del crecimiento del caracol rosado ha sido generado a través de la acuicultura, encierros oceánicos o usando estimaciones derivadas de las dinámicas poblacionales. En este estudio estimamos la tasa de crecimiento de Strombus gigas juvenil en un área natural protegida, por métodos directos durante el período de abril 2009 a enero 2011. Los datos fueron obtenidos por muestras de captura-marca-recaptura. Un total de 1 418 individuos fueron marcados y el crecimiento de 714 caracoles fue analizado. La talla de la población y la densidad relativa fue estimada usando el método de Schnabel. La densidad promedio relativa fue estimada en 0.1694±0.0996ind. m-2, mientras que la densidad más alta fue estimada para septiembre 2010 con 0.3074ind. m-2. La tasa de crecimiento más alta (0.27±0.10mm día-1) fue detectada en juveniles con una talla inicial entre 100-149mm, seguida por juveniles <100mm, con un incremento de 0.24±0.05mm día-1. La tasa de crecimiento disminuyó para individuos con una talla inicial entre 150-199mm (0.18±0.09mm día-1) y para organismos >200mm (0.08 ± 0.07mm día-1). La variabilidad en la tasas de crecimiento fue alta en individuos entre 100-149mm y mostró diferencias estacionales; con la tasa de crecimiento más alta en mayo 2010. El reclutamiento de juveniles más alto se dio en octubre 2009 y en febrero 2010. La población de Xel-Ha ha crecido en tamaño y se pudo encontrar más adultos y juveniles que en estudios anteriores, lo que demuestra que el Parque de Xel-Há está funcionando como un santuario para la conservación del caracol rosado del Caribe en la Riviera Maya de México. La tasa de crecimiento de juveniles en Xel-Ha es alta y presenta grandes variaciones en los individuos, lo ...


Subject(s)
Snails/anatomy & histology , Aquaculture , Protected Areas/analysis , Mexico
6.
Rev. biol. trop ; 60(supl.1): 71-87, Mar. 2012. graf, tab
Article in English | LILACS, SaludCR | ID: lil-657855

ABSTRACT

Annual benthic and fish population surveys were completed at five locations in the nearshore waters along Grenada´s southwest coast during 2008-2010. Two survey sites are located in a newly launched Marine Protected Area (MPA). Photo Quadrat (PQ) and Point Line Intercept (PLI) surveys were used to determine substrate cover. Algae was the primary live cover increasing significantly from 45.9% in 2008 to 52.7% in 2010 (PLI). Algae was also predominant (61.0%-59.3%) in the PQ surveys although annual variation was not significant. Hard coral cover ranged from 16.5% to 15.4% (PLI) and 11.4% to12.0% (PQ) with no significant differences between years. Branching and encrusting corals occurred more frequently than massive corals. In the three annual surveys neither algal cover nor hard coral varied significantly between MPA and non-protected areas (PLI). Relative abundance of fishes along 30x2m belt transects did not vary significantly among years however density of fishes decreased significantly across years for most major groups. Chromis spp. dominated the survey sites at 65.2% in 2008 and 49.8% in 2010, followed by territorial damselfish,11.1% and 15.5%, wrasse increased from 7.3% to 15.5%. Both the substrate cover and fish survey data analyses indicated a stable but degraded community. Annual surveys are planned at these sites for the foreseeable future. Existing and future data from this project will be valuable in determining the efficacy of MPA management, guiding resource management decisions and monitoring the health status of Grenada’s valuable reef systems.


Un estudio sobre poblaciones bentónicas y de peces fue realizado en cinco localidades en la zona costera en el suroeste de Grenada entre 2008 y 2010. Dos sitios se ubicaron en una Área Marina Portegida (AMP) recientemente creada. Para determinar la cobertura se utilizaron foto-cuadrantes (FQ) y transectos de intersección de puntos (TIP). Las algas fueron el principal componente del bentos, aumentando significativamente de 45,9% en 2008 a 52,7% en 2010 (TIP). Las algas también fueron predominantes (61,9%-59,3) en los FQ, aunque las diferencias anuales no fueron significativas. La cobertura de corales pétreos tenía un ámbito de 16,5% a 15,4% (TIP) y de 11,4% a 12,0% (FQ), sin diferencias significativas entre años. Los corales ramificados e incrustantes fueron más frecuentes que los corales masivos. En los tres años no hubo diferencias significativas entre las AMPs y las áreas no protegidas. La abundancia relativa de peces a lo largo de un transecto de 30x2m no varió significativamente entre los años, sin embargo, la densidad de peces decreció significativamente a través de los años, para los grupos principales. Chromis spp. predominó con 65,2% en 2008 y 49,8% en 2012, seguido por damiselas territoriales, 11,1% y 15,5%, y los lábridos aumentaron de 7,3% a 15,5%. Tanto la coberura del sustrato como los datos de peces indican una comunidad estable pero degradada. Sondeos anuales están planeados para el futuro. Los datos existentes y futuros de este proyecto serán muy útiles para determinar la eficacia de la gestión de las AMPs y el estado de salud de los sistemas arrecifales de Grenada.


Subject(s)
Benthic Flora/analysis , Grenada , Seaweed/classification , Spain , Protected Areas/analysis
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