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1.
PLoS One ; 19(7): e0305462, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38990928

RESUMEN

Many habitat-specialist organisms occur in distinct, patchy habitat, yet do not occupy all patches, and an important question is why apparently suitable habitat remains unoccupied. We examined factors influencing patch occupancy in near-threatened, little-known Diademed Plovers (Phegornis mitchellii), arguably the bird most specialized to life in High Andean peatlands. Andean peatlands are well-suited to occupancy modelling because they are discrete patches of humid habitat within a matrix of high-altitude steppe. We hypothesized that Diademed Plovers occupy preferably larger and more humid peatlands, and avoid peatlands used for grazing by llamas and vicuñas, which may trample vegetation and nests. From December 2021 to February 2022 (breeding season), we conducted plover occupancy surveys (2-4) on 40 peatlands at Lagunas de Vilama, a landscape of arid steppe and wetlands above 4,500 m in NW Argentina. We measured peatland size, grazing pressure, topographic and remotely-sensed variables that correlate with humidity, and incorporated these as covariates in occupancy models. Occupancy models showed that more than 50% of the studied peatlands were used by Diademed Plovers and most showed signs of reproduction, highlighting the importance of the Vilama Wetlands for Diademed Plover conservation. Within peatlands, Diademed Plovers were most often associated with headwaters. The top ranked occupancy model included constant detection, random spatial effects, and a single occupancy covariate: mean NDWI (Normalized Difference Water Index, an index correlated with water content and humidity) over the previous three years. Contrary to our prediction, Diademed Plovers preferred less water-saturated peatlands (lower NDWI), possibly to avoid nest flooding. This may be especially important in wet years, like the year when we conducted our surveys. Neither peatland size nor grazing by llamas and vicuñas affected peatland use by Diademed Plovers, suggesting that llama grazing at current levels may be compatible with plover conservation. For organisms that specialize on humid habitats, such as peatlands, factors affecting occupancy may vary temporally with variation in climate, and we recommend follow-up surveys across multi-year timescales to untangle the impact of climate on animals' use of humid habitats.


Asunto(s)
Camélidos del Nuevo Mundo , Ecosistema , Humedad , Animales , Camélidos del Nuevo Mundo/fisiología , Argentina , Humedales , Herbivoria , Especies en Peligro de Extinción , Suelo/química
2.
PLoS One ; 19(7): e0306578, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38959281

RESUMEN

Thoughtfully managed hydroperiods in natural and artificial wetlands could potentially provide a combination of desirable flood control services and high ecological functions. To explore how managed freshwater wetlands typical of the Houston, Texas area would respond to different hydrological regimes that might occur if wetlands were drained in anticipation of a heavy rain that did not materialize, we conducted a mesocosm experiment with six flooding depths and seven drought durations, followed by seven months of recovery. We found that the speed in which mesocosms dried out was a function of initial water depth, with mesocosms initially set with greater water depths (30 cm) taking ~ 38 days to dry out versus zero days for wetlands that were completely drained. Individual plant species (14 species planted; 8 species common at the end of the recovery period) were affected by drought length, flooding depth, or their interaction, although details of these responses varied among the species. The composition of the plant community at the end of the drought period was strongly affected by drought length, and the effect of the drought length treatment persisted through seven months of post-drought recovery, with the 80- and 160-day drought treatments diverging most strongly from shorter drought treatments. Above- and below-ground biomass of plants was not affected by the treatments, but above-ground dead biomass (litter) decreased with increasing drought length. Densities of mosquito larvae, snails and tadpoles were temporally variable, and were affected more during the treatment period and early in recovery than after a disturbance event late in recovery. Our results indicate that managed wetlands in southeast Texas would be quite resilient to dry periods of up to 40 days in duration, especially if water was not completely drained at the beginning of the drought. In addition, many species would persist in managed wetlands even with droughts of up to 160 days. This indicates considerable potential for managing the hydroperiods of artificial detention ponds by retaining water longer to increase ecological function, with little to no loss of flood control services, and for managing the hydroperiods of natural wetlands by draining them in advance of anticipated rains to increase flood control services, with little to no loss of ecological function.


Asunto(s)
Inundaciones , Agua Dulce , Invertebrados , Humedales , Animales , Invertebrados/fisiología , Plantas , Sequías , Texas
3.
J Parasitol ; 110(4): 239-249, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38972666

RESUMEN

In salt marsh ecosystems, daggerblade grass shrimp, Palaemon (Palaemonetes) pugio, play a crucial role in food webs and serve as the definitive host for the bopyrid isopod Probopyrus pandalicola. These ectoparasites infest the branchial chambers of grass shrimp, which can lead to decreased energy availability and sterilization of infected hosts. Although bopyrid isopod infestation of daggerblade grass shrimp has been frequently reported in literature from coastal marshes of the southeastern United States, the prevalence of this parasite has not been recently documented in daggerblade grass shrimp from marshes of the northeastern United States. The goal of this project was to quantify the prevalence of Pr. pandalicola infestations in Pa. pugio across Cape Cod, Massachusetts. We evaluated bopyrid isopod prevalence from shrimp collected from 5 different salt marsh habitats along Cape Cod in August 2021. Bopyrid isopod infestations were found in shrimp at 4 of 5 salt marshes, with prevalence ranging from 0.04 to 14.1%. Seasonal resampling of one of the salt marshes revealed the highest average infestation prevalence in spring (<17.1%) and an isolated high of 30.3% prevalence in a single salt panne. A series of linear and multivariate models showed that panne area, shrimp abundance, and distance to shoreline were related to Pr. pandalicola shrimp infestations in salt pannes in summer. This study describes the prevalence of the bopyrid isopod infesting daggerblade grass shrimp in salt marshes in New England, with implications for how parasitized shrimp influence salt marsh food webs in which they are found.


Asunto(s)
Isópodos , Palaemonidae , Humedales , Animales , Massachusetts/epidemiología , Palaemonidae/parasitología , Prevalencia , Infestaciones Ectoparasitarias/veterinaria , Infestaciones Ectoparasitarias/epidemiología , Infestaciones Ectoparasitarias/parasitología
4.
Sci Adv ; 10(27): eadk5430, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38968357

RESUMEN

Mangroves' ability to store carbon (C) has long been recognized, but little is known about whether planted mangroves can store C as efficiently as naturally established (i.e., intact) stands and in which time frame. Through Bayesian logistic models compiled from 40 years of data and built from 684 planted mangrove stands worldwide, we found that biomass C stock culminated at 71 to 73% to that of intact stands ~20 years after planting. Furthermore, prioritizing mixed-species planting including Rhizophora spp. would maximize C accumulation within the biomass compared to monospecific planting. Despite a 25% increase in the first 5 years following planting, no notable change was observed in the soil C stocks thereafter, which remains at a constant value of 75% to that of intact soil C stock, suggesting that planting effectively prevents further C losses due to land use change. These results have strong implications for mangrove restoration planning and serve as a baseline for future C buildup assessments.


Asunto(s)
Biomasa , Carbono , Suelo , Humedales , Carbono/metabolismo , Suelo/química , Rhizophoraceae/crecimiento & desarrollo , Rhizophoraceae/metabolismo , Teorema de Bayes , Ecosistema
5.
J Environ Sci (China) ; 146: 298-303, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38969458

RESUMEN

Antibiotics, their transformation products, and the translocation of antibiotic-resistant genes in the environment pose significant health risks to humans, animals, and ecosystems, aligning with the One Health concept. Constructed wetlands hold substantial yet underutilized potential for treating wastewater from agricultural, domestic sewage, or contaminated effluents from wastewater treatment plants, with the goal of eliminating antibiotics. However, the comprehensive understanding of the distribution, persistence, and dissipation processes of antibiotics within constructed wetlands remains largely unexplored. In this context, we provide an overview of the current application of stable isotope analysis at natural abundance to antibiotics. We explore the opportunities of an advanced multiple stable isotope approach, where isotope concepts could be effectively applied to examine the fate of antibiotics in wetlands. The development of a conceptual framework to study antibiotics in wetlands using multi-element stable isotopes introduces a new paradigm, offering enhanced insights into the identification and quantification of natural attenuation of antibiotics within wetland systems. This perspective has the potential to inspire the general public, governmental bodies, and the broader research community, fostering an emphasis on the utilization of stable isotope analysis for studying antibiotics and other emerging micropollutants in wetland systems.


Asunto(s)
Antibacterianos , Monitoreo del Ambiente , Contaminantes Químicos del Agua , Humedales , Antibacterianos/análisis , Contaminantes Químicos del Agua/análisis , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química , Isótopos/análisis
6.
Glob Chang Biol ; 30(7): e17388, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38967139

RESUMEN

Permafrost thaw in northern peatlands causes collapse of permafrost peat plateaus and thermokarst bog development, with potential impacts on atmospheric greenhouse gas exchange. Here, we measured methane and carbon dioxide fluxes over 3 years (including winters) using static chambers along two permafrost thaw transects in northwestern Canada, spanning young (~30 years since thaw), intermediate and mature thermokarst bogs (~200 years since thaw). Young bogs were wetter, warmer and had more hydrophilic vegetation than mature bogs. Methane emissions increased with wetness and soil temperature (40 cm depth) and modelled annual estimates were greatest in the young bog during the warmest year and lowest in the mature bog during the coolest year (21 and 7 g C-CH4 m-2 year-1, respectively). The dominant control on net ecosystem exchange (NEE) in the mature bog (between +20 and -54 g C-CO2 m-2 year-1) was soil temperature (5 cm), causing net CO2 loss due to higher ecosystem respiration (ER) in warmer years. In contrast, wetness controlled NEE in the young and intermediate bogs (between +55 and -95 g C-CO2 m-2 year-1), where years with periodic inundation at the beginning of the growing season caused greater reduction in gross primary productivity than in ER leading to CO2 loss. Winter fluxes (November-April) represented 16% of annual ER and 38% of annual CH4 emissions. Our study found NEE of thermokarst bogs to be close to neutral and rules out large CO2 losses under current conditions. However, high CH4 emissions after thaw caused a positive net radiative forcing effect. While wet conditions favouring high CH4 emissions only persist for the initial young bog period, we showed that continued climate warming with increased ER, and thus, CO2 losses from the mature bog can cause net positive radiative forcing which would last for centuries after permafrost thaw.


Asunto(s)
Dióxido de Carbono , Cambio Climático , Gases de Efecto Invernadero , Metano , Hielos Perennes , Humedales , Metano/análisis , Metano/metabolismo , Dióxido de Carbono/análisis , Gases de Efecto Invernadero/análisis , Temperatura , Suelo/química , Canadá , Estaciones del Año
7.
NPJ Biofilms Microbiomes ; 10(1): 55, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38961111

RESUMEN

Climate changes significantly impact greenhouse gas emissions from wetland soil. Specifically, wetland soil may be exposed to oxygen (O2) during droughts, or to sulfate (SO42-) as a result of sea level rise. How these stressors - separately and together - impact microbial food webs driving carbon cycling in the wetlands is still not understood. To investigate this, we integrated geochemical analysis, proteogenomics, and stoichiometric modeling to characterize the impact of elevated SO42- and O2 levels on microbial methane (CH4) and carbon dioxide (CO2) emissions. The results uncovered the adaptive responses of this community to changes in SO42- and O2 availability and identified altered microbial guilds and metabolic processes driving CH4 and CO2 emissions. Elevated SO42- reduced CH4 emissions, with hydrogenotrophic methanogenesis more suppressed than acetoclastic. Elevated O2 shifted the greenhouse gas emissions from CH4 to CO2. The metabolic effects of combined SO42- and O2 exposures on CH4 and CO2 emissions were similar to those of O2 exposure alone. The reduction in CH4 emission by increased SO42- and O2 was much greater than the concomitant increase in CO2 emission. Thus, greater SO42- and O2 exposure in wetlands is expected to reduce the aggregate warming effect of CH4 and CO2. Metaproteomics and stoichiometric modeling revealed a unique subnetwork involving carbon metabolism that converts lactate and SO42- to produce acetate, H2S, and CO2 when SO42- is elevated under oxic conditions. This study provides greater quantitative resolution of key metabolic processes necessary for the prediction of CH4 and CO2 emissions from wetlands under future climate scenarios.


Asunto(s)
Dióxido de Carbono , Metano , Oxígeno , Proteómica , Sulfatos , Humedales , Sulfatos/metabolismo , Oxígeno/metabolismo , Proteómica/métodos , Metano/metabolismo , Dióxido de Carbono/metabolismo , Microbiología del Suelo , Microbiota , Bacterias/metabolismo , Bacterias/clasificación , Bacterias/genética , Cambio Climático
8.
Arch Microbiol ; 206(8): 342, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38967823

RESUMEN

A novel mangrove soil-derived actinomycete, strain S2-29T, was found to be most closely related to Saccharopolyspora karakumensis 5K548T based on 16 S rRNA sequence (99.24% similarity) and genomic phylogenetic analyses. However, significant divergence in digital DNA-DNA hybridization, average nucleotide identity, and unique biosynthetic gene cluster possession distinguished S2-29T as a distinct Saccharopolyspora species. Pan genome evaluation revealed exceptional genomic flexibility in genus Saccharopolyspora, with > 95% accessory genome content. Strain S2-29T harbored 718 unique genes, largely implicated in energetic metabolisms, indicating different metabolic capacities from its close relatives. Several uncharacterized biosynthetic gene clusters in strain S2-29T highlighted the strain's untapped capacity to produce novel functional compounds with potential biotechnological applications. Designation as novel species Saccharopolyspora mangrovi sp. nov. (type strain S2-29T = JCM 34,548T = CGMCC 4.7716T) was warranted, expanding the known Saccharopolyspora diversity and ecology. The discovery of this mangrove-adapted strain advances understanding of the genus while highlighting an untapped source of chemical diversity.


Asunto(s)
ADN Bacteriano , Genoma Bacteriano , Filogenia , ARN Ribosómico 16S , Saccharopolyspora , Microbiología del Suelo , Saccharopolyspora/genética , Saccharopolyspora/metabolismo , Saccharopolyspora/clasificación , ARN Ribosómico 16S/genética , ADN Bacteriano/genética , Familia de Multigenes , Genómica , Análisis de Secuencia de ADN , Humedales , Hibridación de Ácido Nucleico , Técnicas de Tipificación Bacteriana
9.
Environ Monit Assess ; 196(8): 690, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38958832

RESUMEN

Kolonnawa marsh (KM) is an important wetland ecosystem in Colombo district, Sri Lanka that provides essential ecosystem services, and has undergone significant changes over recent decades due to continuous exploitation and reclamation. The values of wetlands are disregarded by decision-makers, despite the fact that they are crucial for improving the quality of water and offer chances for relaxation and amusement in metropolitan areas. Underestimation of the value of wetlands contributes to their continuing deterioration and inevitable loss. Investigating the changes in wetlands can provide crucial information for decision-making. This study aimed to monitor the spatiotemporal land-cover dynamics of KM with the prospect prediction as reduced total extent of KM gradually with time and marsh area being transformed into terrestrial vegetation with time. The collective images from Google Earth (2000 to 2021) and drone data (2022) were analyzed with the GIS application. Subsequently, 50-m2 grid squares with unique cell IDs are designed to link among land cover maps for spatiotemporal land-cover change analysis. Then, we calculate land cover category: surface water, marsh, and terrestrial vegetation proportions for each map in 50-m2 grid cells. Statistical comparison of the land cover changes in grid square cells shows that each land cover category has significant change with the time. The results showed that the reduction of KM marsh resulting in land cover changes has a positive implication on wetland degradation. Thus, interventions should be made for the restoration and sustainable management of KM.


Asunto(s)
Conservación de los Recursos Naturales , Monitoreo del Ambiente , Humedales , Sri Lanka , Monitoreo del Ambiente/métodos , Sistemas de Información Geográfica , Análisis Espacio-Temporal , Ecosistema
10.
Artículo en Inglés | MEDLINE | ID: mdl-38995174

RESUMEN

A novel facultatively anaerobic and Gram-stain-negative bacterium, designated FJH33T, was isolated from mangrove sediment sampled in Zhangzhou, PR China. Cells of strain FJH33T were rod-shaped or slightly curved-shaped, with widths of 0.3-0.5 µm and lengths of 1.0-3.0 µm. Optimum growth of strain FJH33T occurred in the presence of 3 % NaCl (w/v), at 33 °C and at pH 7.0. Oxidase activity was negative, while catalase activity was positive. Its iron-reducing ability was determined. Based on 16S rRNA gene sequence similarity, strain FJH33T was most closely related to Maribellus luteus XSD2T (95.1 %), followed by Maribellus sediminis Y2-1-60T (95.0 %) and Maribellus maritimus 5E3T (94.9 %). Genome analysis of strains FJH33T and M. luteus XSD2T revealed low genome relatedness, with an average nucleotide identity value of 73.8% and a digital DNA-DNA hybridization value of 19.0%. Phylogenetic trees built from 16S rRNA genes and genome sequences showed that strain FJH33T represents a relatively independent phylogenetic lineage within the genus Maribellus. The major cellular fatty acids (≥10 %) were iso-C15 : 0 and C18 : 1 ω9c. The sole respiratory quinone was MK-7. The polar lipids consisted of phosphatidylethanolamine, diphosphatidylcholine, diphosphatidyglycerol and one unidentified lipid. The DNA G+C content was 41.4 mol%. Based on the integrated results of phylogenetic, physiological, biochemical and chemotaxonomic characterizations, we propose that strain FJH33T represents a novel species of the genus Maribellus, for which the name Maribellus mangrovi sp. nov. is proposed. The type strain is FJH33T (=KCTC 102210T=MCCC 1H01459T).


Asunto(s)
Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano , Ácidos Grasos , Sedimentos Geológicos , Hibridación de Ácido Nucleico , Filogenia , ARN Ribosómico 16S , Análisis de Secuencia de ADN , Vitamina K 2 , Sedimentos Geológicos/microbiología , ARN Ribosómico 16S/genética , ADN Bacteriano/genética , China , Vitamina K 2/análogos & derivados , Vitamina K 2/análisis , Hierro/metabolismo , Flavobacteriaceae/clasificación , Flavobacteriaceae/genética , Flavobacteriaceae/aislamiento & purificación , Humedales
11.
PLoS One ; 19(7): e0306321, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38976695

RESUMEN

Phytoplankton community characterized by strong vitality response to environmental change in freshwater ecosystems. This study aims to evaluate the effectiveness of using phytoplankton diversity as a water quality indicator in wetlands, and find out the main environmental variables affecting the distribution of phytoplankton. From 2020 to 2021, we examined phytoplankton assemblages and water environmental variables in spring, summer, and autumn at eight sampling sites from Hulanhe Wetland, Northeast (NE) China. The results showed that Bacillariophyta was the dominant species. Phytoplankton composition and abundance differed among sampling sites in each season; the abundance in summer (613.71 × 104 ind. L-1) was higher than that in autumn and spring. The water quality assessment of the trophic state index (TSI) based on the four physicochemical indicators was compared with phytoplankton diversity indices, which indicated that the phytoplankton community was stable, and these two indices were significantly lower in summer than in spring and autumn. According to redundancy analysis (RDA), total phosphorus (TP) and nitrogen (TN) were the main environmental variables affecting the distribution of phytoplankton. Temperature and dissolved oxygen (DO) changes also played a role, and their impact on the community was discussed. This work can provide relevant scientific references on the usefulness of phytoplankton diversity structure in assessing water quality in cold regions, in which the succession can be significantly affected by nutrients and temperatures.


Asunto(s)
Agua Dulce , Fitoplancton , Estaciones del Año , Calidad del Agua , Humedales , Fitoplancton/crecimiento & desarrollo , China , Agua Dulce/análisis , Fósforo/análisis , Biodiversidad , Monitoreo del Ambiente/métodos , Nitrógeno/análisis , Temperatura
12.
Artículo en Inglés | MEDLINE | ID: mdl-38865172

RESUMEN

Two bacteria, UG2_1T and UG2_2, were isolated from the gill tissues of the mangrove fiddler crab Cranuca inversa collected on the east coast of the Red Sea (Thuwal, Saudi Arabia). The cells are Gram-negative, rod-shaped, orange-pigmented, motile by gliding with no flagella, strictly aerobic, and grow at 20-37 °C (optimum, 28-35 °C), at pH 5.0-9.0 (optimum, pH 6.0-7.0), and with 1-11 % (w/v) NaCl (optimum, 2-4 %). They were positive for oxidase and catalase activity. Phylogenetic analysis based on 16S rRNA gene sequences indicated that isolates UG2_1T and UG2_2 belong to the genus Mangrovimonas, showing the highest similarity to Mangrovimonas spongiae HN-E26T (99.4 %). Phylogenomic analysis based on the whole genomes, independently using 49 and 120 concatenated genes, showed that strains UG2_1T and UG2_2 formed a monophyletic lineage in a different cluster from other type strain species within the genus Mangrovimonas. The genome sizes were 3.08 and 3.07 Mbp for UG2_1T and UG2_2, respectively, with a G+C content of 33.8 mol% for both strains. Values of average nucleotide identity and digital DNA-DNA hybridization between the strains and closely related species were 91.0 and 43.5 %, respectively. Chemotaxonomic analysis indicated that both strains had iso-C15 : 0 and iso-C15 : 1 G as dominant fatty acids, and the primary respiratory quinone was identified as MK-6. The major polar lipids comprised phosphatidylethanolamine, one unidentified glycolipid, one unidentified phospholipid, two unidentified aminolipids, and four unidentified lipids. Based on phylogenetic, phylogenomic, genome relatedness, phenotypic, and chemotaxonomical data, the two isolates represent a novel species within the genus Mangrovimonas, with the proposed name Mangrovimonas cancribranchiae sp. nov., and the type strain UG2_1T (=KCTC 102158T=DSM 117025T).


Asunto(s)
Técnicas de Tipificación Bacteriana , Composición de Base , Braquiuros , ADN Bacteriano , Ácidos Grasos , Branquias , Hibridación de Ácido Nucleico , Filogenia , ARN Ribosómico 16S , Análisis de Secuencia de ADN , ARN Ribosómico 16S/genética , Ácidos Grasos/análisis , ADN Bacteriano/genética , Océano Índico , Animales , Branquias/microbiología , Braquiuros/microbiología , Arabia Saudita , Humedales , Vitamina K 2/análogos & derivados , Vitamina K 2/análisis , Fosfolípidos/análisis
13.
Ying Yong Sheng Tai Xue Bao ; 35(4): 1016-1024, 2024 Apr 18.
Artículo en Chino | MEDLINE | ID: mdl-38884236

RESUMEN

In this study, we explored the changes in plant community diversity and their relationship with soil factors under shrub encroachment pressure by selecting four marsh areas in Sanjiang Plain with different degrees of shrub cover (a, 0≤a≤100%), including marsh with no shrub encroachment (a=0), light shrub encroachment (0

Asunto(s)
Biodiversidad , Suelo , Humedales , China , Suelo/química , Dinámica Poblacional , Poaceae/crecimiento & desarrollo , Plantas/clasificación , Desarrollo de la Planta
14.
Ying Yong Sheng Tai Xue Bao ; 35(4): 1044-1054, 2024 Apr 18.
Artículo en Chino | MEDLINE | ID: mdl-38884239

RESUMEN

Aiming to understand the responses of soil seed bank to different water levels, we investigated vegetation and soil seed bank along a water level gradient (frequently flooded area, unflooded area) on the floodplain wetland of Juzhang River. We used the structural equation model to explore the direct and indirect effects of water level on soil seed bank, and used non-metric multidimensional scaling (NMDS) to assess the role of soil seed bank for vegetation regeneration. The results showed that the density of transient and persistent seed banks at unflooded area was 36.9% and 7.8% higher than that of frequently flooded area, respectively. Shannon index and Pielou index of seed bank and vegetation were significantly affected by water level and sampling location. Water level significantly affected the similarity between seed bank and aboveground vegetation, and the similarity of persistent seed bank with aboveground vegetation was significantly higher than that with transient seed bank. Structural equation model showed that water level had a direct effect on seed bank density, and indirect effects on density and richness of seed bank via affecting soil pH and NH4+-N content. NMDS results showed that there was no significant difference in the composition of the persistent seed bank and vegetation community in autumn under different water levels, but water level significantly changed the community composition of transient seed bank. Transient seed bank was affected by the vegetation and soil property, while persistent seed bank was determined by aboveground vegetation and water level. Although soil seed bank had low regeneration potential for the vegetation communities in floodplain wetlands, soil seed bank could not be neglected during the restoration of propagule diversity after disturbance in wetlands. Persistent seed bank would be an importance source of diversity of propagules for floodplain wetlands restoration following disturbance.


Asunto(s)
Ríos , Suelo , Humedales , China , Suelo/química , Inundaciones , Conservación de los Recursos Naturales , Semillas/crecimiento & desarrollo , Ecosistema , Movimientos del Agua , Banco de Semillas
15.
Water Sci Technol ; 89(11): 3104-3121, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38877633

RESUMEN

Coastal wetlands are the main distribution of blue carbon in coastal zones and well known for their high carbon sequestration capacity. Investigating the variation of carbon budget is crucial for understanding the functionality of coastal wetlands and effectively addressing climate change. In this study, a bibliometric analysis of 4,509 articles was conducted to reveal research progress, hot issues, and emerging trends in the coastal wetland carbon budget field. The number of publications and citations in this field increased exponentially from 1991 to 2022. The leading subject category was Environmental Sciences with 1,844 articles (40.9%). At present, studies have been focused on blue carbon, the effects of climate change and man-made disturbances on carbon cycle, and the restoration of coastal wetlands. Based on the hotspots and trends in this field, the future researches should include (1) exploring the functional mechanisms of various factors affecting carbon cycle and establishing a methodological system for the estimation of blue carbon in coastal wetlands; (2) researching restoration techniques of coastal wetland and constructing wetland restoration evaluation index system; and (3) formulating enforceable carbon trading policy and strengthening international cooperation.


Asunto(s)
Bibliometría , Carbono , Humedales , Carbono/metabolismo , Cambio Climático
16.
Mar Pollut Bull ; 204: 116535, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38833948

RESUMEN

As human activities become more intensive, a substantial number of heavy metals are discharged into estuarine or wetland environments. Due to the poor degradability, heavy metals are prone to adsorption and deposition on suspended particles in bottom sediments. Subsequently, under the influence of disturbances, there is a potential for their re-release, causing secondary pollution. To investigate the release process of the heavy metal Cr from sediment, laboratory experiments were conducted under both unidirectional flow and regular wave conditions. At the initial stage, the temporal trends of particulate (CrP) and dissolved (CrD) Chromium concentrations were both characterized by initial increments followed by stabilization and continuous escalation. Vertically, the stable concentrations of CrP and CrD increased with the presence of vegetation and the enhancement of hydrodynamics. The Elovich equation, pseudo-second-order kinetic equation, Double constant equation (Freundlich model), and parabolic diffusion equation were employed to predict the release process of CrD from bottom sediment. The Elovich equation proved most suitable for describing the release process of CrD, with an R2 exceeding 0.9. In order to assess the influence of vegetation on the Cr release process, the Stem-Reynolds were introduced to modify the Elovich equation. The final maximum error was 12 % (excluding the initial stage), which was much lower than that using the original Elovich equation (maximum error of 32 %). The study findings provide practical support for estuarine and wetland managers to formulate effective heavy metal management measures, which contribute to the conservation and sustainable management of aquatic ecosystems.


Asunto(s)
Cromo , Sedimentos Geológicos , Metales Pesados , Contaminantes Químicos del Agua , Sedimentos Geológicos/química , Contaminantes Químicos del Agua/análisis , Cromo/análisis , Metales Pesados/análisis , Monitoreo del Ambiente , Plantas , Humedales , Movimientos del Agua
17.
Curr Microbiol ; 81(8): 224, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38874676

RESUMEN

Grapsoid crabs (Decapoda: Grapsoidea) inhabiting along the land-sea transition provided various amounts and quality of vascular plant carbon (e.g., fresh mangrove leaf, leaf litter, and mangrove-derived organic carbon) and perform differing levels of herbivory. Other than endogenous cellulase, symbiotic cellulolytic bacteria could also contribute to the crabs' vascular plant carbon assimilation and mineralization. In this study, we isolated culturable cellulolytic bacteria from three gut regions (i.e., stomach, midgut, and hindgut) of 15 species of grapsoid crabs that inhabit in various coastal habitats (i.e., land margin, mangrove forest, tidal flat, and subtidal area). Bacillus, which was isolated from 11 out of the 15 grapsoid crabs, was the most common genus of culturable prominently cellulolytic bacteria among the target species. Seventy to ninety nine percent of culturable cellulolytic bacteria were removed, and the endoglucanase activity of five species was significantly reduced by 14.4-27.7% after antibiotic treatment. These results suggest that cellulolytic bacteria play a role in assisting mangrove carbon utilization in coastal grapsoid crabs, especially those inhabiting mangrove, mudflat, and subtidal areas. The significantly higher abundance of cellulolytic bacteria and the generally higher hydrolytic capacity of the bacteria in mangrove crab species suggest that they receive more contribution from symbionts for mangrove carbon utilization, while semi-terrestrial crabs seem to depend little on symbiotic cellulase due to the lower abundances.


Asunto(s)
Celulosa , Microbioma Gastrointestinal , Humedales , Animales , Celulosa/metabolismo , Braquiuros/microbiología , Bacterias Aerobias/metabolismo , Bacterias Aerobias/fisiología , Celulasa/metabolismo , Simbiosis , Tracto Gastrointestinal/microbiología , Carbono/metabolismo
18.
Sci Total Environ ; 941: 173740, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38839002

RESUMEN

Constructed wetlands (CWs) have been used to enhance pollutant removal by filling several types of material as substrates. However, research on substrate filling order remains still limited, particularly regarding the effects of greenhouse gas (GHG) emissions. In this study, six CWs were constructed using zeolite and ferric­carbon micro-electrolysis (Fe-C) fillers to evaluate the effect of changing the filling order and ratio on pollutant removal, GHGs emissions, and associated microbial structure. The results showed that the order of substrate filling significantly impacted pollutant removal performance on CWs. Specifically, CWs filled with zeolite in the top layer exhibited superior NH4+-N removal compared to those filled in the lower layer. Moreover, the highest NH4+-N removal (95.0 % ± 1.9 %) was observed in CWs with a zeolite to Fe-C volume ratio of 8:2 (CWZe-1). Moreover, zeolite-filled at the top had lower GHGs emissions, with the lowest CH4 (0.22 ± 0.10 mg m-2 h-1) and N2O (167.03 ± 61.40 µg m-2 h-1) fluxes in the CWZe-1. In addition, it is worth noting that N2O is the major contributor to integrated global warming potential (GWP) in the six CWs, accounting for 81.7 %-90.8 %. The upper layer of CWs filled with zeolite exhibited higher abundances of nirK, nirS and nosZ genes. The order in which the substrate was filled affected the microbial community structure and the upper layer of CWs filled with zeolite had higher relative abundance of nitrifying genera (Nitrobacter, Nitrosomonas) and denitrifying genera (Zoogloea, Denitratisoma). Additionally, N2O emission was reduced by approximately 41.2 %-64.4 % when the location of the aeration of the CWs was changed from the bottom to the middle. This study showed that both the order of filling the substrate and the aeration position significantly affected the GHGs emissions from CWs, and that CWs had lower GHGs emissions when zeolites were filled in the upper layer and the aeration position was in the middle.


Asunto(s)
Contaminantes Atmosféricos , Metano , Óxido Nitroso , Eliminación de Residuos Líquidos , Humedales , Metano/análisis , Óxido Nitroso/análisis , Eliminación de Residuos Líquidos/métodos , Contaminantes Atmosféricos/análisis , Zeolitas/química , Gases de Efecto Invernadero/análisis
19.
J Water Health ; 22(6): 1075-1087, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38935458

RESUMEN

This study evaluated pesticide exposure practices, and the potential health risks of drinking water and consuming fish from the cultivated wetlands of Ndop, Cameroon. Six hundred and twenty-six questionnaires were conveniently administered to farmers (≥ 26 years old) in a cross-sectional study to assess exposure practices and dietary risks. The Chi-square and Pearson correlation coefficients were used to establish relationships between variables. The PRIMET model was used to predict a worst-case dietary risk. The pesticide handling practices of 90% of farmers were inadequate. Chlorpyriphos, lambda-cyhalothrin, fipronil, and paraquat dichloride posed a possible dietary risk at recommended and applied doses, with chlorpyrifos having the highest exposure toxicity ratio (ETRdiet = 36.72). Paraquat dichloride, fipronil, and lambda-cyhalothrin posed a possible dietary risk at 26.3%, 58.3%, and 62.2% of their recommended concentrations, respectively. Remarkably, the dietary risk for cypermethrin was acceptable at 5.8 times its recommended dose (ETRdietR = 0.29). The significant positive correlation (p = 0.000) between PECfish and ETRdiet, suggests a possible health risk of consuming fish and drinking water harvested from the wetlands, thus the need for replacing pesticides posing possible risks at lower or recommended concentrations with less toxic alternatives and to train farmers on pesticide application practices.


Asunto(s)
Agua Potable , Peces , Plaguicidas , Contaminantes Químicos del Agua , Humedales , Agua Potable/análisis , Agua Potable/química , Animales , Medición de Riesgo , Humanos , Contaminantes Químicos del Agua/análisis , Plaguicidas/análisis , Camerún , Estudios Transversales , Contaminación de Alimentos/análisis , Dieta , Exposición Dietética/análisis , Adulto , Agricultura , Encuestas y Cuestionarios
20.
Biol Lett ; 20(6): 20240062, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38923948

RESUMEN

Diatom cell-size composition is an indicator of aquatic environmental changes but has been rarely investigated, especially in semi-terrestrial peatlands. In this study, both taxonomic composition and cell-size composition of diatoms were analysed in 41 samples from two montane peatlands, northeastern China. Redundancy analyses revealed that diatom taxonomic composition was significantly related to the depth to the water table (DWT) and Ca2+, while cell-size composition was significantly associated with DWT and Si. DWT was the most important factor and its sole effect explained 26.2% and 17.9% of the total variance in taxonomic composition and cell-size composition, respectively. Accordingly, diatom-based water-table transfer functions were developed based on taxonomic composition and cell-size composition, respectively. The maximum-likelihood (ML) model based on diatom taxonomic composition had the best performance, with a correlation coefficient value (R2) of 0.78 and the root mean squared error of prediction (RMSEP) of 6.66 cm. The ML model based on cell-size composition had similar performance, with an R2 of 0.78 and the RMSEP of 6.87 cm, suggesting that diatom cell-size composition can be a new quantitative means to track past water-table changes. This method requires further appraisal with palaeoecological data but offers a new option that deserves exploration.


Asunto(s)
Diatomeas , Diatomeas/clasificación , Diatomeas/citología , China , Agua Subterránea , Humedales , Suelo , Tamaño de la Célula
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