Evaluation of Two Ecosystem Services Provided by a Pistia stratiotes Population on the Pacific Coast of South America.

One of the most fascinating wetlands on Peru's central coast is the Santa Rosa wetland (Chancay, Lima), an ecosystem threatened by anthropogenic activities. Some of these impacts have led to the uncontrolled growth of Pistia stratiotes, an invasive aquatic plant. This study sought to quantify the regulation and provisioning of ecosystem services provided by P. stratiotes using carbon storage and the provision of biomass as indicators. To this end, the biomasses of 50 plots measuring 0.0625 m2 were weighed and georeferenced and the percentages of dry biomass (%DB) and total organic carbon in the biomass (%C) were quantified. The biomass and its coordinates were entered into ArcGIS and a Kriging interpolation technique was applied to determine the total amount of biomass (B). It was found that P. stratiotes stored 3942.57 tCO2 and that 2132.41 tons of biomass could be obtained for fodder. The total carbon stored by this aquatic plant represented 28.46% of the total carbon sequestered in the wetland ecosystem by vascular plants, suggesting that its contribution to the carbon cycle is significant. This is the first study to estimate the biomass of a floating aquatic plant population in a coastal Peruvian wetland and is a pioneering study addressing the in situ carbon estimation of Peruvian floating aquatic plants. The results and methods proposed in this research will serve in the evaluation of the potential of ecosystem services among similar populations of floating aquatic species. In addition, the data presented can be used to establish plans for the management and use of this biomass in the production of soil fertilizers and cattle forage.

Combining multisensor images and social network data to assess the area flooded by a hurricane event.

In this study, multisensor remote sensing datasets were used to characterize the land use and land covers (LULC) flooded by Hurricane Willa which made landfall on October 24, 2018. The landscape characterization was done using an unsupervised K-means algorithm of a cloud-free Sentinel-2 MultiSpectral Instrument (MSI) image, acquired during the dry season before Hurricane Willa. A flood map was derived using the histogram thresholding technique over a Synthetic Aperture Radar (SAR) Sentinel-1 C-band and combined with a flood map derived from a Sentinel-2 MSI image. Both, the Sentinel-1 and Sentinel-2 images were obtained after Willa landfall. While the LULC map reached an accuracy of 92%, validated using data collected during field surveys, the flood map achieved 90% overall accuracy, validated using locations extracted from social network data, that were manually georeferenced. The agriculture class was the dominant land use (about 2,624 km2), followed by deciduous forest (1,591 km2) and sub-perennial forest (1,317 km2). About 1,608 km2 represents the permanent wetlands (mangrove, salt marsh, lagoon and estuaries, and littoral classes), but only 489 km2 of this area belongs to aquatic surfaces (lagoons and estuaries). The flooded area was 1,225 km2, with the agricultural class as the most impacted (735 km2). Our analysis detected the saltmarsh class occupied 541 km2in the LULC map, and around 328 km2 were flooded during Hurricane Willa. Since the water flow receded relatively quickly, obtaining representative imagery to assess the flood event was a challenge. Still, the high overall accuracies obtained in this study allow us to assume that the outputs are reliable and can be used in the implementation of effective strategies for the protection, restoration, and management of wetlands. In addition, they will improve the capacity of local governments and residents of Marismas Nacionales to make informed decisions for the protection of vulnerable areas to the different threats derived from climate change.

Spatial distribution and characteristics of plastic pollution in the salt marshes of Bahía Blanca Estuary, Argentina.

This study delves into the magnitude and attributes of plastic pollution in the salt marshes of the Bahía Blanca Estuary, Argentina, with a specific focus on its spatial distribution. The investigation included the evaluation of microplastics (1-5 mm), mesoplastics (5-25 mm) and macroplastics (25-100 mm), discovering elevated levels along the high salt marsh strandline compared to low salt marsh and mudflat areas. Notably, the abundance of plastic reached staggering levels, reaching up to 20,060 items/m2 in the vicinity of an illegal dumpsite. Microplastics, particularly in the 2-4 mm range, were dominant, and the main plastic components were high-density polyethylene (HDPE), low-density polyethylene (LDPE), polypropylene (PP), and polystyrene (PS). Plastic films emerged as the predominant plastic type, while the presence of pellets hinted at potential sources such as illegal dumping and port-related activities. This contamination could be largely attributed to inappropriate waste management practices and urban runoff, which pose a substantial ecological threat to these ecosystems. Urgent remedial action is essential to protect these marshes, underscoring the critical need for comprehensive wetland management and educational initiatives to ensure their long-term sustainability.

Insects associated to ephemeral pools in Huentelauquén (29ºS Coquimbo Region, Chile) / Insetos associados a lagoas temporárias em Huentelauquén (29ºS Região de Coquimbo, Chile)

Abstract In northern central Chile, ephemeral pools constitute shallow isolated water bodies with a favourable habitat for fauna adapted to seasonal changes. Based on the limited knowledge about the fauna—particularly insects—associated to these ecosystems, the objective of this study was to characterize the richness, composition, structure and similarity of the insect communities associated with ephemeral pools in Huentelauquén (29º S, Coquimbo Region, Chile). By using pitfall traps, 10,762 individuals were captured, represented by 7 orders, 27 families, and 51 species. Coleoptera and Hymenoptera were the best represented orders, with Neuroptera, Orthoptera and Plecoptera being poorly represented groups. The non-parametric estimators evaluated showed wealth values above those observed for all the studied pools, and their accumulation curves suggest the existence of an incomplete species inventory in the studied community. Additionally, the hierarchical and ordering analysis showed groupings of pools located in the northwest and southeast of Huentelauquén. Preliminarily we found a negative correlation between the area of the pools and the richness (species) and abundance of insects. Additional studies (on other arthropod groups and other seasons of the year) could provide a better understanding of the local processes of extinction and colonization of the species inhabiting these fragile coastal environments.

Resumo No norte central do Chile, lagoas efêmeras constituem corpos de água isolados e pouco profundos, com um habitat favorável para a fauna adaptada as mudanças sazonais que as zonas úmidas estão sujeitas. Com relação a estes ecossistemas, sabe-se pouco sobre sua fauna, principalmente a de insetos. O objetivo do presente estudo foi caracterizar a riqueza, composição, estrutura e similaridade das comunidades de insetos que habitam as lagoas temporárias de Huentelauquén (29º S, Região de Coquimbo, Chile). Usando armadilhas de interceptação, se capturou um total de 10.762 indivíduos, pertencentes a 7 ordens, 27 famílias e 51 espécies. Coleoptera e Hymenoptera foram as ordens mais representativas, enquanto Neuroptera, Orthoptera e Plecoptera foram grupos pouco representativos. Os estimadores não paramétricos avaliados mostraram valores de riqueza superiores ao observados para todas as lagoas estudadas, e suas curvas de acumulação parecem indicar que o inventario da comunidade estudada está incompleto. A análise hierárquica e de ordenamento revelou agrupamentos de lagoas correspondentes a zona nordeste e sudeste de Huentelauquén. Preliminarmente encontramos uma correlação negativa entre a área de lagoas efêmeras e a riqueza (espécies) e abundância de insetos. É necessário realizar estudos adicionais (sobre outros grupos de artrópodes e em outras estações do ano) para melhor compreensão dos processos locais de extinção e colonização das espécies que habitam estes frágeis ambientes costeiros estudados.

Insects associated to ephemeral pools in Huentelauquén (29ºS Coquimbo Region, Chile)

Abstract In northern central Chile, ephemeral pools constitute shallow isolated water bodies with a favourable habitat for fauna adapted to seasonal changes. Based on the limited knowledge about the faunaparticularly insectsassociated to these ecosystems, the objective of this study was to characterize the richness, composition, structure and similarity of the insect communities associated with ephemeral pools in Huentelauquén (29º S, Coquimbo Region, Chile). By using pitfall traps, 10,762 individuals were captured, represented by 7 orders, 27 families, and 51 species. Coleoptera and Hymenoptera were the best represented orders, with Neuroptera, Orthoptera and Plecoptera being poorly represented groups. The non-parametric estimators evaluated showed wealth values above those observed for all the studied pools, and their accumulation curves suggest the existence of an incomplete species inventory in the studied community. Additionally, the hierarchical and ordering analysis showed groupings of pools located in the northwest and southeast of Huentelauquén. Preliminarily we found a negative correlation between the area of the pools and the richness (species) and abundance of insects. Additional studies (on other arthropod groups and other seasons of the year) could provide a better understanding of the local processes of extinction and colonization of the species inhabiting these fragile coastal environments.

Resumo No norte central do Chile, lagoas efêmeras constituem corpos de água isolados e pouco profundos, com um habitat favorável para a fauna adaptada as mudanças sazonais que as zonas úmidas estão sujeitas. Com relação a estes ecossistemas, sabe-se pouco sobre sua fauna, principalmente a de insetos. O objetivo do presente estudo foi caracterizar a riqueza, composição, estrutura e similaridade das comunidades de insetos que habitam as lagoas temporárias de Huentelauquén (29º S, Região de Coquimbo, Chile). Usando armadilhas de interceptação, se capturou um total de 10.762 indivíduos, pertencentes a 7 ordens, 27 famílias e 51 espécies. Coleoptera e Hymenoptera foram as ordens mais representativas, enquanto Neuroptera, Orthoptera e Plecoptera foram grupos pouco representativos. Os estimadores não paramétricos avaliados mostraram valores de riqueza superiores ao observados para todas as lagoas estudadas, e suas curvas de acumulação parecem indicar que o inventario da comunidade estudada está incompleto. A análise hierárquica e de ordenamento revelou agrupamentos de lagoas correspondentes a zona nordeste e sudeste de Huentelauquén. Preliminarmente encontramos uma correlação negativa entre a área de lagoas efêmeras e a riqueza (espécies) e abundância de insetos. É necessário realizar estudos adicionais (sobre outros grupos de artrópodes e em outras estações do ano) para melhor compreensão dos processos locais de extinção e colonização das espécies que habitam estes frágeis ambientes costeiros estudados.

Thirty-year changes of the coastlines, wetlands, and ecosystem services in the Asia major deltas.

Coastal zones are usually composed of coastlines and coastal wetlands and are among the most productive and dynamic ecosystems. However, the deltas are seldom detected and compared in detail at the continental scale to investigate the spatiotemporal evolution of coastline migration and coastal wetlands. Here we detected and compared the spatiotemporal changes in coastlines, wetlands, and ecosystem services in major deltas in Asia, including the Yellow River Delta (YRD), Yangtze River Delta (YAD), Pearl River Delta (PRD), Red River Delta (RRD), Mekong River Delta (MERD), Chao Phraya River Delta (CPRD), Mahanadi River Delta (MARD), Krishna River Delta (KRD), and Indus River Delta (IRD). We used time series remote sensing images from 1990 to 2019 to derive coastline and wetland information for the nine coastal zones. The ecosystem service value coefficients were applied to explore the ecosystem services characteristics of wetland changes in coastal areas. We found that the coastlines of the deltas in the study area changed less in the bedrock and sandy coasts, while the coastlines in the silty delta coasts changed more from 1990 to 2019. The interannual dynamics of coastal wetland areas in nine major deltas over the nearly 30 years can be divided into three periods: decreasing variability (1990-2005), increasing variability (2005-2015), and increasing volatility (2015-2019). Ecosystem services had an overall downward trend. These findings complement the official database of coastal planning and have substantial guiding implications for adjusting coastal management regulation policies.

Variability of the community structure of aquatic macroinvertebrates in the Salinas de Chilca, Lima, Peru / Variabilidad de la estructura comunitaria de macroinvertebrados acuáticos en las salinas de chilca, lima, perú

RESUMEN Las Salinas de Chilca están localizadas en el km 65 de la carretera Panamericana Sur, representadas por tres lagunas: La Milagrosa (laguna principal y pozas salinas), La Mellicera y La Encantada. El entorno de estas lagunas pertenece a la zona de vida Desierto Subtropical (d-ST). El objetivo del presente estudio fue determinar la influencia de las variables ambientales en los cambios de la estructura comunitaria de macroinvertebrados en las Salinas de Chilca, Lima, Perú. Se realizaron cuatro campañas de colecta desde enero hasta septiembre del 2018, estableciéndose doce estaciones de muestreo, tres estaciones por cada ambiente léntico. La muestra fue colectada a través de barridos con una red tipo D de 500 µm de apertura de malla en la orilla de cada laguna. Los parámetros fisicoquímicos del agua presentaron valores diferenciados en cada laguna y formaron una gradiente de salinidad descendente desde las pozas salinas (de valores hipersalinos) hacia la laguna La Encantada (de valores mesosalinos). Se recolectaron 42 géneros de macroinvertebrados, siendo los géneros más influyentes en los patrones comunitarios: Heleobia, Larsia, Trichocorixa, EphydrayArtemia, estos organismos representaron el 83,85 % de la abundancia total. El gradiente ambiental generado por la salinidad determinó dos grupos muy diferenciados, un grupo de especies que no toleran valores elevados de salinidad (lagunas mesosalinas) de otro grupo de especies que soportan valores extremos de salinidad (lagunas hipersalinas); sin embargo, la depredación, alteraciones antrópicas, estructura del hábitat, entre otros factores, también estarían influyendo en los cambios de la estructura comunitaria.

ABSTRACT The Salinas de Chilca are located at km 65 of the Panamericana Sur highway, represented by three lagoons: La Milagrosa (main lagoon and salt ponds), La Mellicera and La Encantada. The environment of these lagoons belongs to the Subtropical Desert (d-ST) life zone. The objective of the present study was to determine the influence of environmental variables on changes in the macroinvertebrate community structure in the Salinas de Chilca, Lima, Peru. Four collection campaigns were carried out from January to September 2018, establishing twelve sampling stations, three stations for each lentic environment. The sample was collected through sweeps with a 500 µm mesh opening type D network on the shore of each lagoon. The physicochemical parameters of the water presented different values in each lagoon and formed a descending salinity gradient from the saline pools (with hypersaline values) towards the La Encantada lagoon (with mesosaline values). 42 genera of macroinvertebrates were collected, with the most influential genera in community patterns: Heleobia, Larsia, Trichocorixa, Ephydra and Artemia, these organisms represented 83.85 % of the total abundance. The environmental gradient generated by salinity determined two very different groups, a group of species that do not tolerate high salinity values (mesosaline lagoons) from another group of species that support extreme salinity values (hypersaline lagoons); however, predation, anthropic alterations, habitat structure, among other factors, would also be influencing changes in the community structure.

Free-living Microturbellarians (Platyhelminthes) from Wetlands in Southern Brazil, with the Description of Three New Species.

The Taim strict nature reserve (ESEC Taim) is a protected wetland (Ramsar site) in southern Brazil. Although the ESEC Taim harbours a broad conspicuous flora and fauna, this area lacks studies on free-living Platyhelminthes. Here, we describe three new species to science, one belonging to Macrostomorpha (Macrostomum itai n. sp.) and two belonging to Dalytyphloplanoida (Gieysztoria duopunctata n. sp. and G. hermes n. sp.). Macrostomum itai n. sp. differs from their congeners for its distinct stylet in "J"-shaped. Gieysztoria duopunctata n. sp. is distinguishable based on the crown-like penis stylet, this species possesses 12-18 spines of similar sizes and two smaller spines (one a bit longer than the other). Gieysztoria hermes n. sp. clearly differs from its congeners owing to its fibrous girdle, which bears two groups of complexes of spines and three different-in-length ventral spines. Moreover, we identified twenty-three species, eleven belonging to Catenulida, three to Macrostomorpha, seven to Dalytyphloplanoida, one to Kalyptorhynchia, and one to Prorhynchida. We recorded three species for the first time in Brazil (Myostenostomum vanderlandi, Macrostomum quiritium and Strongylostoma elongatum). This new information on these free-living Platyhelminthes makes this protected area a more valuable and reinforces the actions that are being done to protect it.

Future carbon emissions from global mangrove forest loss.

Mangroves have among the highest carbon densities of any tropical forest. These 'blue carbon' ecosystems can store large amounts of carbon for long periods, and their protection reduces greenhouse gas emissions and supports climate change mitigation. Incorporating mangroves into Nationally Determined Contributions to the Paris Agreement and their valuation on carbon markets requires predicting how the management of different land-uses can prevent future greenhouse gas emissions and increase CO2 sequestration. We integrated comprehensive global datasets for carbon stocks, mangrove distribution, deforestation rates, and land-use change drivers into a predictive model of mangrove carbon emissions. We project emissions and foregone soil carbon sequestration potential under 'business as usual' rates of mangrove loss. Emissions from mangrove loss could reach 2391 Tg CO2 eq by the end of the century, or 3392 Tg CO2 eq when considering foregone soil carbon sequestration. The highest emissions were predicted in southeast and south Asia (West Coral Triangle, Sunda Shelf, and the Bay of Bengal) due to conversion to aquaculture or agriculture, followed by the Caribbean (Tropical Northwest Atlantic) due to clearing and erosion, and the Andaman coast (West Myanmar) and north Brazil due to erosion. Together, these six regions accounted for 90% of the total potential CO2 eq future emissions. Mangrove loss has been slowing, and global emissions could be more than halved if reduced loss rates remain in the future. Notably, the location of global emission hotspots was consistent with every dataset used to calculate deforestation rates or with alternative assumptions about carbon storage and emissions. Our results indicate the regions in need of policy actions to address emissions arising from mangrove loss and the drivers that could be managed to prevent them.

Trabajos originales Preferencia de hábitats y estacionalidad de las especies de aves de los Pantanos de Villa en Lima, Perú / Habitat preferences and seasonality of bird species of Pantanos de Villa in Lima, Peru

Resumen En el Refugio de Vida Silvestre Pantanos de Villa se analizó la preferencia de hábitat de las aves residentes y migratorias en función a la estacionalidad de 211 especies de aves, de las cuales 97 son residentes, 82 migratorias y 32 visitantes ocasionales. De acuerdo con el uso de los hábitats: 80.1% de especies habitan en cualquiera de los hábitats de pantanos, 40.8% en el litoral marino, 37.9% en parques y jardines, 33.2% en pantanos y la playa marina, 34.1% en pantanos y los parques y jardines y 1.0% en la playa arenosa marina y los parques y jardines. La mayor similitud de especies se encuentra entre las que habitan en la zona arbustiva y parques y jardines con 82.3%. La intensidad de las fluctuaciones de la riqueza de especies varía según el hábitat que ocupan con los mayores valores entre marzo y mayo en los espejos de agua (25) y en el litoral marino (24). La gestión de Pantanos de Villa debe priorizar el mantenimiento de la heterogeneidad de hábitats debido a la baja similitud entre varios de ellos y exclusividad de especies para los mismos. La comparación entre las preferencias de hábitat de las aves y las plantas muestra que es necesario tener en cuenta más de un taxón en la toma de decisiones para el manejo y conservación de la biodiversidad de los humedales costeros.

Abstract In the wildlife refuge Pantanos de Villa, habitat preferences of resident and migratory birds were analyzed according to the seasonality of 211 species of birds, of which 97 were residents, 82 migratories and 32 occasional visitors. According to use of habitats: 80.1% of species live on any of these wetlands, 40.8% in the marine coast, 37.9% in parks and gardens, 33.2% in wetlands and the beach, 34.1% in wetlands and parks and gardens and 1.0% in marine sandy beach and parks and gardens. Higher species similarity was between those living in "shrubland zones" and "parks and gardens" (82.3%). Fluctuation intensity of the species richness varied according to their occupance habitats, with the highest value observed between March and May in the water bodies (25) and marine coast (24). Management of the Pantanos de Villa must prioritize maintenance of heterogeneity of habitats because the low similarity degree would show species exclusivity of each of them. Comparisons between preferences of habitats of birds and plants would demonstrate the need of consider more than one taxa in decision-making for the management and conservation of biodiversity of coastal wetlands.

Variación espacial de la comunidad de macroinvertebrados acuáticos en la zona litoral del humedal costero Santa Rosa, Lima, Perú

Los humedales costeros son ecosistemas sensibles de alta productividad por los servicios ecosistémicos que brindan: purificación del agua, reducción de las inundaciones, protección de las costas marinas y; además, son lugares de gran diversidad biológica. El objetivo del presente estudio fue determinar la estructura comunitaria de los macroinvertebrados acuáticos en relación con las variaciones espaciales en la zona litoral del humedal costero Santa Rosa en Lima, Perú. El estudio fue realizado en seis periodos bimestrales desde agosto 2015 a junio 2016. Se establecieron ocho estaciones de muestreo: tres estaciones en la laguna principal, tres estaciones en el brazo de la laguna y dos estaciones en pozas pequeñas aisladas. Los muestreos se realizaron con una red tipo D de 250 μm de apertura de malla y tres réplicas por cada estación. Las ocho estaciones evaluadas se caracterizaron ambientalmente y se registraron los parámetros fisicoquímicos del agua para cada estación. Se recolectaron en total 28 655 macroinvertebrados distribuidos en 76 géneros. Los órdenes de mayor riqueza fueron: Diptera y Coleoptera con 24 y 19 géneros respectivamente. De estos últimos, los más abundantes fueron: Buenoa (Hemiptera: Notonectidae), Ischnura (Odonata: Coenagrionidae), Chironomus y Goeldichironomus (Diptera: Chironomidae). Estos cuatro representaron el 62.43 % de la abundancia total. En cuanto a la variación espacial, la mayor parte de las estaciones de estudio compartieron la misma estructura y composición de macroinvertebrados debido a que se conectan al cuerpo de agua principal de manera temporal o permanente, lo cual les confirió una estabilidad y resiliencia mayor. Solo las estaciones con una baja profundidad, menor extensión, escasa vegetación acuática e impacto antropogénico mayor se apartaron del conjunto general. A pesar de los variados impactos producidos por la agricultura, ganadería y la actividad urbana que sufre el humedal, se observó que las estaciones más profundas y con cobertura vegetal son más resilientes que las zonas expuestas al impacto y con menor volumen de agua y vegetación. Por otro lado, los parámetros fisicoquímicos del agua en la primera estación (E1) se diferencian al resto de la comunidad por su ausencia de impacto.

Coastal wetlands are sensitive ecosystems of high productivity due to ecological services they provide: water purification, flood reduction, and protection of marine coasts. In addition, these zones are places of great biological diversity. The objective of the present study was to determine the community structure of the aquatic macroinvertebratesin relation to the spatial variations in the littoral zone of the Santa Rosa coastal wetland in Lima, Peru. The study was carried out during six bimonthly periods from August 2015 to June 2016. We established eight sampling sites: three sites in the main lagoon, three sites in the lagoon arm and two sites in isolated small pools. We carried out the sampling with a D-frame of 250 μm mesh aperture with three replicates for each site. The eight evaluated sites were environmentally characterized, and the physicochemical parameters of the water were recorded for each sampling site. We collected 28 655 macroinvertebrates distributed in 76 genera. Diptera and Coleoptera were the orders with the greatest richness: 24 and 19 genera respectively. The most abundant genera were: Buenoa (Hemiptera: Notonectidae), Ischnura (Odonata: Coenagrionidae), Chironomus and Goeldichironomus (Diptera: Chironomidae); these four represented 62.43 % of the total abundance. In the spatial variation, most sites shared the same structure and composition of macroinvertebrates. This was expected because they are connected to the main water body temporarily or permanently, which consequently gives them greater stability and resilience. The sites with shallow depth, smaller extension, scarce aquatic vegetation and greater anthropogenic impact were the only ones with results separated from the general set. Due to the variety of environmental impacts produced by agriculture, livestock, and urban activity on the wetland, it was observed that the sites with deeper and more abundant vegetation were more resilient than the areas exposed to environmental impacts and with less water and vegetation. On the other hand, the physicochemical parameters of water at one site (E1) differentiate the community in the absence of impact.

Variación espacio-temporal de la respuesta espectral en manglares de La Habana, Cuba, evaluada con sensores remotos / Spatio-temporal variations of the spectral response in mangroves of Havana, Cuba, by remote sensing

Introducción: Los manglares son una de las formaciones vegetales de mayor relevancia global por los servicios ecosistémicos y roles ecológicos que desempeñan, y representan el 5 % de la superficie emergida de Cuba. No existen estudios previos que describan las variaciones en los índices espectrales de vegetación por sensores remotos en los manglares cubanos, pero con este tipo de variable se pueden constituir indicadores del estado de estos ecosistemas y emplearse en evaluaciones a nivel nacional. Objetivo: En el presente trabajo se evalúa la variabilidad espacial y temporal de dos índices espectrales de vegetación en cuatro manglares periurbanos de la ciudad de La Habana y se comparan con un sitio natural como control. Métodos: El estudio se desarrolló en las localidades de Bajo de Santa Ana, Cojímar, Rincón de Guanabo y la laguna El Cobre - Itabo y el control fue tomado en la ciénaga de Zapata. A través de la plataforma Climate Engine se extrajeron, de 2 460 imágenes satelitales LandSat, los valores promedio de los índices espectrales NDVI y EVI en 5 parcelas por cada localidad de estudio, entre 1984 y 2019. Las variables se compararon estadísticamente entre localidades y se describió su tendencia a lo largo del periodo de estudio. Resultados: Se detectaron diferencias geográficas en los índices, que pueden correlacionarse con las propiedades estructurales y grado de conservación de cada localidad. La tendencia global de los índices fue a un aumento, pero difirió entre localidades. Los menores cambios se produjeron en el sitio control y, entre los humedales periurbanos, en el Rincón de Guanabo y en Cojímar. El ordenamiento de las localidades a partir de variables espectrales fue consistente con el de grado de conservación general. Conclusiones: La respuesta espectral permitió caracterizar cada manglar de manera individualizada, mostrando relación aparente con las características ecológicas y de conservación de cada lugar. Es necesario continuar promoviendo estudios con sensores remotos de estas formaciones boscosas y generar indicadores sólidos que sustenten su uso en futuras investigaciones y monitoreos en manglares del Caribe.

Introduction: Mangroves are one of the most important forest types because of their ecosystem services and ecological roles. They represent 5 % of the emerged land of Cuba. No previous studies are describing spectral vegetation indexes variations by remote sensing in Cuban mangroves, but these variables can be used as indicators of the conservation status of the ecosystem and sustain national wide assessments. Objective: In the current paper we describe spatial and temporal variations in two spectral vegetation indexes in four near-city mangroves at Havana, Cuba and compare them to a natural control site. Methods: Study was conducted in localities named: Bajo de Santa Ana, Cojímar, Rincón de Guanabo, and El Cobre - Itabo lagoon and as control site was selected northern Zapata swamp. By using Climate Engineplatform we extract, from 2 460 Landsat satellite images, mean values of spectral indexes NDVI and EVI in 5 parcels per locality, from 1984 to 2019. Variables were statistically compared among localities and the global trend was described. Results: We detect geographic differences in both indexes, which can be related to structural properties and conservation degree of mangroves in each locality. Global trend of indexes was to increase, but differently among localities. Slighter changes appear in the control site and, among near city mangroves, in Rincón de Guanabo and Cojímar. The ordering of localities from spectral variables was consistent with the ranking in general conservation degree. Conclusions: Spectral responses describe uniquely each mangrove forest, in concordance to each ecological and conservation characteristics. There is a need for promoting studies using remote sensors at these forest types and to generate strong and reliable indicators that can sustain future researches and monitoring schemes in Caribbean mangroves.

New genus and species of Delphacini (Hemiptera: Delphacidae) from a salt marsh in northern Chile.

Salinesia atacamensis gen. et sp. nov. is described from a coastal wetland of Atacama Region, Chile. It is characterized by the small size (males < 2 mm), dorsal side concolorous, with lateral carinae of pronotum reaching hind margin, armature of male pygofer narrow and not produced, phallus curved ventrad, and abdominal segment X of male without processes.

Influence of sediment granulometry and salinity on the composition of an estuarine fish assemblage in the Mexican Tropical Pacific / Influencia de la granulometría del sedimento y la salinidad en la composición de una comunidad de peces estuarinos en el Pacífico tropical mexicano

Abstract Barra de Navidad lagoon (BNL) is one of the main coastal wetlands in the coast of the State of Jalisco, Mexico. It is a Ramsar site (wetland of international importance) and has been included among the 81 mangrove sites with biological relevance and ecological rehabilitation needs in Mexico. Although fish fauna composition is well known in BNL, little evidence exists that support seasonal and spatial changes of fish assemblages' structure. The hypothesis tested in this study was that there are significant seasonal and spatial changes in BNL fish assemblages' composition which can be explained, at least partially, by changes in salinity, water temperature and sediment's granulometry. Fish assemblages were sampled monthly from October 2012 to September 2013 at four zones of BNL, using gill nets (7.62 mm stretched mesh). A sample was taken every month in a randomly selected area of each zone. Prior to each sampling operation, water salinity and temperature were measured using an YSI-30 probe. Samples of sediment were collected with a Van Veen grab sampler in three randomly selected points of each zone for granulometry and organic matter analyses. A total of 2 026 individuals belonging to 48 species were collected. Slightly more than 90 % of all caught fish belonged to nine species: Peruvian mojarra (Diapterus brevirostris), Pacific crevalle-jack (Caranx caninus), White mullet (Mugil curema), Blue sea-catfish (Ariopsis guatemalensis), Oval flounder (Syacium ovale), Pacific lined sole (Achirus mazatlanus), Yellowfin mojarra (Gerres simillimus), Pacific bumper (Chloroscombrus orqueta) and Freckled porcupinefish (Diodon holocanthus). Generalized linear models yielded significant differences among zones for the mean abundance of each of these nine species, but only in two cases seasonal differences were significant (D. brevisrostris and C. caninus). Permutational multivariate analysis of variance yielded also significant differences among zones and between seasons for the composition of the fish assemblage. Redundancy analysis using salinity, temperature, and percentage mud in sediment as environmental variables showed that fish assemblage's composition varies along two main gradients defined by mud fraction of sediments in a small spatial scale (~ 3 km) and salinity in a seasonal scale. Percentage of variation explained by canonical axes was less than 25 %, indicating that other factors could be influencing changes in assemblage composition. As most species appear as juveniles in the lagoon, fluctuations in their abundances could be linked, at least partially, with recruitment events. Rev. Biol. Trop. 66(3): 1065-1077. Epub 2018 September 01.

Resumen La laguna Barra de Navidad (LBN) es uno de los principales humedales costeros en la costa del Estado de Jalisco, México. Es un sitio Ramsar (humedal de importancia internacional) y ha sido incluida entre los 81 sitios de manglar con relevancia biológica y necesidades de rehabilitación en México. Aunque la composición de la ictiofauna es bien conocida en LBN, hay poca evidencia sobre la existencia de cambios estacionales y espaciales en la estructura de la misma. La hipótesis que guió este trabajo fue que en la composición de la ictiofauna de la laguna Barra de Navidad hay cambios espaciales y estacionales que pueden ser explicados, al menos parcialmente, por cambios en la salinidad, temperatura del agua y granulometría del sedimento. Los peces fueron muestreados mensualmente de octubre 2012 a septiembre 2013 en cuatro zonas de la laguna, usando redes agalleras (7.62 mm de malla estirada). Se tomó una muestra cada mes en un área seleccionada aleatoriamente en cada zona. Previo a cada operación de muestreo, se midieron la salinidad y la temperatura del agua con una sonda YSI-30. Muestras de sedimento para análisis granulométrico y del contenido de materia orgánica, se recolectaron con una draga tipo Van Veen en tres puntos seleccionados aleatoriamente en cada zona. Se recolectaron 2 026 individuos de 48 especies de peces. Poco más de 90 % de todos los peces contados pertenecieron a nueve especies: Diapterus brevirostris, Caranx caninus, Mugil curema, Ariopsis guatemalensis, Syacium ovale, Achirus mazatlanus, Gerres simillimus, Chloroscombrus orqueta y Diodon holocanthus. Modelos lineales generalizados arrojaron diferencias significativas entre zonas para la abundancia media de estas nueve especies, pero solo en dos casos se encontraron diferencias significativas entre estaciones (D. brevirostris y C. caninus). El análisis multidimensional de varianza basado en permutaciones, arrojó también diferencias significativas entre zonas y entre estaciones para la composición de la ictiofauna. El análisis de redundancia usando la salinidad, la temperatura y el porcentaje de lodo en el sedimento como variables ambientales, mostró que la composición de la ictiofauna varía a lo largo de dos gradientes definidos por la fracción de lodo de los sedimentos en una escala espacial pequeña (~ 3 km) y la salinidad en una escala estacional. El porcentaje de variación explicado por los ejes canónicos fue menor de 25 %, indicando que otros factores pudieran influir en los cambios de la composición de la ictiofauna. Como la mayoría de las especies aparecen en su estadio juvenil en la laguna, las fluctuaciones en sus abundancias pudieran estar relacionadas, al menos parcialmente, con eventos de reclutamiento.

Sarcocornia neei as an Indicator of Environmental Pollution: A Comparative Study in Coastal Wetlands of Central Chile.

Being adapted to saline environments, halophytes are plant species that have received considerable attention due to their ability to cope with environmental stress factors, such as high concentrations of soluble salts and heavy metals. In this work, we focused on determining if the Sarcocornia neei (S. neei) plant can be considered as an indicator of heavy metal pollution in soil. This was done by analyzing the concentration of cadmium (Cd), lead (Pb), copper (Cu), and arsenic (As) in plants and soil sampled from two wetlands in the central zone of Chile: a wetland contaminated by industrial activities and a wetland protected by the Chilean government. In addition, 14 fertility parameters (pH, electrical conductivity, organic matter, nitrogen (N), phosphorus (P), potassium (K), sodium (Na), Pb, calcium (Ca), magnesium (Mg), Manganese (Mn), zinc (Zn), iron (Fe), and boron (B)) were analyzed for soil samples in both wetlands. This was done to differentiate between available elements and contamination by heavy metals. Plant and soil samples in the contaminated wetland exhibited significantly higher heavy metal concentrations in comparison to samples analyzed from the protected wetland. This indicates that the S. neei plant can be further researched as an indicator of heavy metal pollution in saline soils and possibly for phytoremediation purposes.

Are acid volatile sulfides (AVS) important trace metals sinks in semi-arid mangroves?

Acid-volatile sulfides (AVS) formation and its role on trace metals bioavailability were studied in semi-arid mangroves. The semi-arid climatic conditions at the studied sites, marked by low rainfall and high evapotranspiration rates, clearly limited the AVS formation (AVS contents varied from 0.10 to 2.34µmolg-1) by favoring oxic conditions (Eh>+350mV). The AVS contents were strongly correlated with reactive iron and organic carbon (r=0.84; r=0.83 respectively), evidencing their dominant role for AVS formation under semi-arid conditions. On the other hand, the recorded ΣSEM/AVS values remained >1 evidencing a little control of AVS over the bioavailability of trace metals and, thus, its minor role as a sink for toxic metals.

Producción espacial y temporal de hojarasca del manglar en la laguna Barra de Navidad, Jalisco, México / Spatial and temporal mangrove litter production in Barra de Navidad lagoon, Jalisco, México

ResumenLa laguna de Barra de Navidad es un humedal costero de importancia internacional (sitio RAMSAR) y está incluida entre los 81 sitios prioritarios de manglar de México. Una de las características de mayor valor de la laguna, es la presencia de bosques de mangle en buen estado de conservación. El objetivo de nuestro trabajo, fue medir la producción de hojarasca del manglar y los factores ambientales que pueden influir en su dinámica.El manglar fue dividido en siete zonas y las recolectas de hojarasca se realizaron mensualmente entre noviembre 2011 y octubre 2012, mediante recolectores cuadrados de 0.25 m2 construidos con malla de mosquitero (1 mm) y colocados a 1.3 m del suelo. De forma simultánea, se midieron varias variables abióticas en el agua intersticial recolectada en pozos permanentes en cada zona, mediante un Sistema Multi-Sonda, YSI-556-M. El valor total promedio de producción de hojarasca, según el área de cada zona, fue de 19.12 ± 1.23 gPS/m2.mes (2.29 t/ha.año). Esta baja productividad se atribuye al clima seco de la región y a la poca amplitud de las mareas. Avicennia germinans y Laguncularia racemosa produjeron poco más del 80 % de toda la hojarasca, mientras que Rhizophora mangle sólo contribuyó con el 16 % y Conocarpus erectus< 4%. Existe una correlación significativa entre las variables abióticas del sustrato (principalmente la salinidad y la profundidad del agua intersticial) y la cantidad de hojarasca producida. Se concluye que, existen variaciones espaciales significativas en las variables abióticas del sustrato que se correlacionan con diferencias en la composición por especies del manglar y que, junto con las etapas de los ciclos vitales de esas especies, generan variaciones significativas en la cantidad y composición de la hojarasca producida. La investigación futura se enfocará en la cuantificación de las variaciones espaciales de la estructura del bosque y su relación con la producción de hojarasca.

AbstractBarra de Navidad lagoon is a coastal wetland of international importance (Ramsar site) and it is included among the 81 Mexican mangrove priority sites. One of the most valued characteristics of this lagoon is the presence of mangrove forest in a good conservation state. The goal of our research was the measurement of mangrove litter production and environmental factors influencing its dynamics. The mangrove area was divided into seven zones and litterfall was monthly sampled from November 2011 to October 2012 using 0.25 m2 square collectors made with mosquito mesh (1 mm) and positioned at 1.3 m above the ground. Abiotic variables of the interstitial water were measured simultaneously at each zone in permanent plots using a multi-parameter probe, YSI-556-M. Total mean value of litterfall production, weighted by zone surface, was 19.12 ± 1.23 gPS/m2.mo (2.29 t/ha.year). This low productivity is a consequence of the region's dry climate and low tide range. The species Avicennia germinans and Laguncularia racemosa produced more than 80 % of total litterfall, while Rhizophora mangle contributed only 16 % and Conocarpus erectus < 4 %. A significant correlation between litterfall production and abiotic variables was found (e.g. salinity and interstitial water depth). We concluded that there are significant spatial variations in soil abiotic variables which are correlated with differences in mangrove species composition, and produce, together with the life cycles stages of those species, significant variations in the quantity and composition of litterfall. Future research will be focused on quantifying spatial variations in forest structure and their relationship with litterfall production.