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1.
J Environ Sci (China) ; 147: 462-473, 2025 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39003062

RESUMEN

Lake Baiyangdian is one of China's largest macrophyte - derived lakes, facing severe challenges related to water quality maintenance and eutrophication prevention. Dissolved organic matter (DOM) was a huge carbon pool and its abundance, property, and transformation played important roles in the biogeochemical cycle and energy flow in lake ecosystems. In this study, Lake Baiyangdian was divided into four distinct areas: Unartificial Area (UA), Village Area (VA), Tourism Area (TA), and Breeding Area (BA). We examined the diversity of DOM properties and sources across these functional areas. Our findings reveal that DOM in this lake is predominantly composed of protein - like substances, as determined by excitation - emission matrix and parallel factor analysis (EEM - PARAFAC). Notably, the exogenous tyrosine-like component C1 showed a stronger presence in VA and BA compared to UA and TA. Ultrahigh - resolution mass spectrometry (FT - ICR MS) unveiled a similar DOM molecular composition pattern across different functional areas due to the high relative abundances of lignan compounds, suggesting that macrophytes significantly influence the material structure of DOM. DOM properties exhibited specific associations with water quality indicators in various functional areas, as indicated by the Mantel test. The connections between DOM properties and NO3N and NH3N were more pronounced in VA and BA than in UA and TA. Our results underscore the viability of using DOM as an indicator for more precise and scientific water quality management.


Asunto(s)
Monitoreo del Ambiente , Lagos , Lagos/química , China , Monitoreo del Ambiente/métodos , Eutrofización , Sustancias Húmicas/análisis , Calidad del Agua , Espectrometría de Masas/métodos , Contaminantes Químicos del Agua/análisis , Ecosistema
2.
Environ Geochem Health ; 46(8): 267, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38954229

RESUMEN

This study examines the levels of heavy metals in polyculture fish (Labeo rohita, Cyprinus carpio, and Catla catla), water, and sediment in Tanda Dam, Kohat, Pakistan, aiming to understand environmental and health risks. Samples of fish, water, and sediment were collected from 3 fish farms, and heavy metal concentrations were measured using a Flame Atomic Absorption Spectrophotometer (AAS). Results reveal that C. catla exhibited significantly higher (p < 0.05) levels of Zn than other fish species. Conversely, C. carpio showed significantly higher (p < 0.05) concentrations of Pb, Cd, Cr, Mn, Cu, As, and Ni than other species. The heavy metal hierarchy in C. carpio was found to be Zn > Cu > Pb > Cr > Cd > Mn > As > Ni. While heavy metal levels in L. rohita and C. catla generally fell within reference ranges, exceptions were noted for Zn, Pb, and Cd. Conversely, in C. carpio, all metals exceeded reference ranges except for Cu and Ni. Principal Component Analysis (PCA) indicated a close relationship between water and sediment. Additionally, cluster analysis suggested that C. catla formed a distinct cluster from L. rohita and C. carpio, implying different responses to the environment. Despite concerns raised by the Geoaccumulation Index (Igeo) and Contamination Factor (CF), particularly for Cd, which exhibited a high CF. Furthermore, Hazard Index (HI) values for all three fish species were below 1, suggesting low health risks. However, elevated Igeo and CF values for Cd suggest significant pollution originating from anthropogenic sources. This study underscores the importance of monitoring heavy metals in water for both environmental preservation and human health protection. Future research efforts should prioritize pollution control measures to ensure ecosystem and public health safety.


Asunto(s)
Monitoreo del Ambiente , Sedimentos Geológicos , Metales Pesados , Contaminantes Químicos del Agua , Metales Pesados/análisis , Animales , Contaminantes Químicos del Agua/análisis , Humanos , Medición de Riesgo , Sedimentos Geológicos/química , Monitoreo del Ambiente/métodos , Pakistán , Ecosistema , Carpas/metabolismo , Peces/metabolismo , Análisis de Componente Principal , Acuicultura
3.
Biol Lett ; 20(7): 20240171, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38955224

RESUMEN

Arboreality has evolved in all major vertebrate lineages and is often associated with morphological adaptations and increased diversification concomitant with accessing novel niche space. In squamate reptiles, foot, claw, and tail morphology are well-studied adaptations shown to be associated with transitions to arboreality. Here, we examined a less well understood trait-the keeled scale-in relation to microhabitat, climate, and diversification dynamics across a diverse lizard radiation, Agamidae. We found that the ancestral agamid had keeled dorsal but not ventral scales; further, dorsal and ventral keels are evolutionarily decoupled. Ventral keeled scales evolved repeatedly in association with arboreality and may be advantageous in reducing wear or by promoting interlocking when climbing. We did not find an association between keeled scales and diversification, suggesting keels do not allow finer-scale microhabitat partitioning observed in other arboreal-associated traits. We additionally found a relationship between keeled ventral scales and precipitation in terrestrial species where we posit that the keels may function to reduce scale degradation. Our results suggest that keeled ventral scales facilitated transitions to arboreality across agamid lizards, and highlight a need for future studies that explore their biomechanical function in relation to microhabitat and climate.


Asunto(s)
Evolución Biológica , Ecosistema , Lagartos , Animales , Lagartos/fisiología , Lagartos/anatomía & histología , Escamas de Animales/anatomía & histología , Escamas de Animales/fisiología , Filogenia , Clima
4.
Proc Biol Sci ; 291(2026): 20240778, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38955231

RESUMEN

Mammals influence nearly all aspects of energy flow and habitat structure in modern terrestrial ecosystems. However, anthropogenic effects have probably altered mammalian community structure, raising the question of how past perturbations have done so. We used functional diversity (FD) to describe how the structure of North American mammal palaeocommunities changed over the past 66 Ma, an interval spanning the radiation following the K/Pg and several subsequent environmental disruptions including the Palaeocene-Eocene Thermal Maximum (PETM), the expansion of grassland, and the onset of Pleistocene glaciation. For 264 fossil communities, we examined three aspects of ecological function: functional evenness, functional richness and functional divergence. We found that shifts in FD were associated with major ecological and environmental transitions. All three measures of FD increased immediately following the extinction of the non-avian dinosaurs, suggesting that high degrees of ecological disturbance can lead to synchronous responses both locally and continentally. Otherwise, the components of FD were decoupled and responded differently to environmental changes over the last ~56 Myr.


Asunto(s)
Biodiversidad , Fósiles , Mamíferos , Animales , Mamíferos/fisiología , América del Norte , Ecosistema , Evolución Biológica
5.
J Acoust Soc Am ; 156(1): 137-150, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38958489

RESUMEN

The artificial reefs in New York's waters provide structure in areas that are typically flat and sandy, creating habitat for a multitude of species as an area to spawn, forage, and reside. Passive acoustic data collected on the Fire Island and Shinnecock artificial reefs between 2018 and 2022 detected spawning-associated calls of weakfish (Cynoscion regalis) and Atlantic cod (Gadus morhua), as well as the presence of individual bottlenose dolphins (Tursiops truncatus) through their signature whistles. Weakfish and Atlantic cod were more vocally active on the Fire Island reef, where Atlantic cod grunts peaked during a new moon phase in December, and weakfish spawning experienced variable peaks between mid-July and mid-August on both reefs. Fifty-seven individual bottlenose dolphins were identified, with whistle repeats ranging from seconds to years apart. Passive acoustic monitoring allows for simultaneous collection of information on multiple species at different trophic levels as well as behavioral information that helps managers understand how these animals utilize these habitats, which can lead to improved conservation measures.


Asunto(s)
Acústica , Delfín Mular , Gadus morhua , Vocalización Animal , Animales , Delfín Mular/fisiología , Gadus morhua/fisiología , Arrecifes de Coral , Reproducción/fisiología , Ecosistema , Monitoreo del Ambiente/métodos , Femenino , Perciformes/fisiología
6.
Environ Geochem Health ; 46(8): 278, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38958772

RESUMEN

Miyun Reservoir plays a vital role as a source of drinking water for Beijing, however it grapples with nitrogen contamination issues that have been poorly understood in terms of their distribution, source, and associated health risks. This study addresses this knowledge gap by employing data on nitrate nitrogen (NO3--N), chloride (Cl-), dual isotopic compositions of NO3- (δ15N-NO3- and δ18O-NO3-) data in water ecosystems, systematically exploring the distribution, source and health risk of nitrogen contaminants in Miyun reservoir watersheds. The results showed that over the past 30 years, surface water runoff has exhibited a notable decrease and periodic fluctuations due to the combined influence of climate and anthropogenic activities, while the total nitrogen (TN) concentration in aquatic ecosystems presented an annual fluctuating upward trend. The TN concentration in the wet season was predominantly elevated because a large amount of nitrogen contaminants migrated into water ecosystems through heavy rainfall or river erosion. The concentration of NO3--N, the main contaminant of the water ecosystems, showed distinct variations across different watersheds, followed as rivers over the Miyun reservoir. Moreover, NO3--N levels gradually increased from upstream to downstream in different basins. NO3--N in surface water was mainly derived from the mixture of agricultural ammonia fertilizer and sewage and manure, with a minority of samples potentially undergoing denitrification. Comparatively, the main sources of NO3--N in groundwater were soil N and sewage and manure, while the denitrification process was inactive. The carcinogenic risks caused by NO3--N in groundwater were deemed either nonexistent or minimal, while the focus should predominantly be on potential non-carcinogenic risks, particularly for infants and children. Therefore, it is crucial to perform proactive measures aimed at safeguarding water ecosystems, guided by an understanding of the distribution, sources, and associated risks of nitrogen contamination.


Asunto(s)
Ecosistema , Monitoreo del Ambiente , Nitrógeno , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Medición de Riesgo , China , Nitrógeno/análisis , Abastecimiento de Agua , Nitratos/análisis , Humanos
7.
Environ Monit Assess ; 196(8): 688, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38958799

RESUMEN

Rivers are vital and complex natural systems that provide a wide range of ecosystem services. This study presents a methodology for assessing the riverine provisioning and supporting ecosystem services, whose applicability has been demonstrated over the Budhabalanga River Basin of India. The Soil and Water Assessment Tool (SWAT) is used to generate streamflow time series at various ungauged sites, and then the streamflow is characterized for the evaluation of provisioning services. Further, the diversity and abundance of macroinvertebrates, along with the Lotic-invertebrate Index for Flow Evaluation (LIFE), is used to study the riverine supporting ecosystem services. The streams show intermittent behavior and strong seasonality for low flows, which limits the water availability, particularly during pre-monsoon season. The Baseflow Index (BFI) is greater than 0.6, indicating that groundwater contributes more than 60% of the total streamflow. Interestingly, despite the high BFI, the streams did not conform to the prevailing opinion that a greater baseflow contribution results in a later commencement of the low-flow period in the hydrological year. Furthermore, the study depicts significant variations in the diversity and abundance of the macroinvertebrates across the various sampling sites. However, the LIFE score across the sites remained consistent within a narrow range, i.e., 8 to 9, suggesting a steady supply of supporting ecosystem services. The results of the study can help the policymakers towards an informed decision making and the simplistic methodology proposed in this study can be replicated in other river basins for identifying vulnerable watersheds and prioritizing management actions.


Asunto(s)
Ecosistema , Monitoreo del Ambiente , Hidrología , Ríos , India , Monitoreo del Ambiente/métodos , Animales , Invertebrados , Conservación de los Recursos Naturales/métodos , Biodiversidad , Agua Subterránea
8.
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
9.
Environ Sci Technol ; 58(26): 11675-11684, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38952298

RESUMEN

Excessive anthropogenic phosphorus (P) emissions put constant pressure on aquatic ecosystems. This pressure can be quantified as the freshwater eutrophication potential (FEP) by linking P emissions, P fate in environmental compartments, and the potentially disappeared fraction of species due to increase of P concentrations in freshwater. However, previous fate modeling on global and regional scales is mainly based on the eight-direction algorithm without distinguishing pollution sources. The algorithm fails to characterize the fate paths of point-source emissions via subsurface pipelines and wastewater treatment infrastructure, and exhibits suboptimal performance in accounting for multidirectional paths caused by river bifurcations, especially in flat terrains. Here we aim to improve the fate modeling by incorporating various fate paths and addressing multidirectional scenarios. We also update the P estimates by complementing potential untreated point-source emissions (PSu). The improved method is examined in a rapidly urbanizing area in Taihu Lake Basin, China in 2017 at a spatial resolution of 100 m × 100 m. Results show that the contribution of PSu on FEP (62.6%) is greater than that on P emissions (58.5%). The FEP is more spatially widely distributed with the improved fate modeling, facilitating targeted regulatory strategies tailored to local conditions.


Asunto(s)
Eutrofización , Agua Dulce , Fósforo , Agua Dulce/química , Modelos Teóricos , Monitoreo del Ambiente , China , Contaminantes Químicos del Agua/análisis , Ecosistema
10.
Elife ; 122024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38949865

RESUMEN

Spatial and temporal associations between sympatric species underpin biotic interactions, structure ecological assemblages, and sustain ecosystem functioning and stability. However, the resilience of interspecific spatiotemporal associations to human activity remains poorly understood, particularly in mountain forests where anthropogenic impacts are often pervasive. Here, we applied context-dependent Joint Species Distribution Models to a systematic camera-trap survey dataset from a global biodiversity hotspot in eastern Himalayas to understand how prominent human activities in mountain forests influence species associations within terrestrial mammal communities. We obtained 10,388 independent detections of 17 focal species (12 carnivores and five ungulates) from 322 stations over 43,163 camera days of effort. We identified a higher incidence of positive associations in habitats with higher levels of human modification (87%) and human presence (83%) compared to those located in habitats with lower human modification (64%) and human presence (65%) levels. We also detected a significant reduction of pairwise encounter time at increasing levels of human disturbance, corresponding to more frequent encounters between pairs of species. Our findings indicate that human activities can push mammals together into more frequent encounters and associations, which likely influences the coexistence and persistence of wildlife, with potential far-ranging ecological consequences.


Asunto(s)
Biodiversidad , Bosques , Actividades Humanas , Mamíferos , Animales , Humanos , Ecosistema , Análisis Espacio-Temporal
11.
PLoS One ; 19(7): e0297730, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38950009

RESUMEN

Oceanographic connectivity in an effective network of protected areas is crucial for restoring and stabilising marine populations. However, temporal variability in connectivity is rarely considered as a criterion in designing and evaluating marine conservation planning. In this study, indicators were defined to characterise the temporal variability in occurrence, flux, and frequency of connectivity in a northwestern Mediterranean Sea area. Indicators were tested on semi-theoretically-estimated connections provided by the runs of a passive particle transport model in a climatological year and in three years between 2006-2020, showing large deviation from the climatological year. The indicators allowed comparing the temporal variability in connectivity of four zones, highlighted differences in connectivity due to their locations and the mesoscale hydrodynamics, and identified areas that require further investigation. The three indicators also showed that the temporal variability in connectivity was influenced by the duration and depth of particle transport, although no consistent pattern was observed in the indicator variations of the compared zones. Provided that specific objectives will be given when parameterising transport models (i.e., selection of focus species and time period), indicators of temporal variability in connectivity have potential to support spatial conservation planning, prioritise the protection of marine resources, and measure the effectiveness of Marine Protected Areas, in line with a long-term vision of ocean management.


Asunto(s)
Conservación de los Recursos Naturales , Mar Mediterráneo , Conservación de los Recursos Naturales/métodos , Modelos Teóricos , Ecosistema , Hidrodinámica
12.
PLoS One ; 19(7): e0306110, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38950048

RESUMEN

The rational use of cultivated land can guarantee food security and thus is highly important for ensuring social stability, economic development and national security. The current study investigated the multifunctional temporal and spatial variation characteristics of cultivated land and explored the spatial and temporal characteristics of the multifunction and coupling coordination degrees of cultivated land throughout Hebei Province. Based on the administrative division data, statistical yearbook data and land use status data of the impacted areas, a multifunctional evaluation index system of cultivated land was established. The CRITIC weight method and entropy weight method were used to determine the weight of the index, the comprehensive index model was used to determine the production, social security, ecology and landscape functions of cultivated land of Hebei Province in different periods, the coupling coordination model was used to explore the multifunctional coupling coordination degree of cultivated land in each county, and spatial autocorrelation analysis was performed to determine the correlation of the multifunctional coupling coordination degrees. From 2000 to 2020, the production, social security and landscape function of cultivated land in Hebei Province trended upward; the ecological function trended slightly downward. The multifunctional coupling coordination degree of cultivated land in Hebei Province trended significantly upward and changed from limited coordination to intermediate coordination. Furthermore, it exhibited strong agglomeration and a significant positive spatial correlation, forming a 'V'-type change rule of first decreasing and then increasing. Hebei Province exhibited remarkable spatial and temporal characteristics of the multifunction and coupling coordination degrees of cultivated land. Regions could thus customize different cultivated land functions to maximize the benefits of cultivated land use. The findings of this study may provide a scientific basis and theoretical support for sustainably using and managing cultivated land resources in areas with similar human geographical environments.


Asunto(s)
Agricultura , Análisis Espacio-Temporal , China , Agricultura/métodos , Conservación de los Recursos Naturales/métodos , Humanos , Ecosistema
13.
PeerJ ; 12: e17694, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38952975

RESUMEN

Background: Invasive species are the primary threat to island ecosystems globally and are responsible for approximately two-thirds of all island species extinctions in the past 400 years. Non-native mammals-primarily rats, cats, mongooses, goats, sheep, and pigs-have had devastating impacts on at-risk species and are major factors in population declines and extinctions in Hawai'i. With the development of fencing technology that can exclude all mammalian predators, the focus for some locations in Hawai'i shifted from predator control to local eradication. Methods: This article describes all existing and planned full predator exclusion fences in Hawai'i by documenting the size and design of each fence, the outcomes the predator eradications, maintenance issues at each fence, and the resulting native species responses. Results: Twelve predator exclusion fences were constructed in the Hawaiian Islands from 2011-2023 and six more were planned or under construction; all were for the protection of native seabirds and waterbirds. Fences ranged in length from 304-4,877 m and enclosed 1.2-640 ha. One-third of the 18 fences were peninsula-style with open ends; the remaining two-thirds of the fences were complete enclosures. The purpose of twelve of the fences (67%) was to protect existing bird populations, and six (33%) were initiated for mitigation required under the U.S. Endangered Species Act. Of the six mitigation fences, 83% were for the social attraction of seabirds and one fence was for translocation of seabirds; none of the mitigation fences protected existing bird populations. Rats and mice were present in every predator exclusion fence site; mice were eradicated from five of six sites (83%) where they were targeted and rats (three species) were eradicated from eight of 11 sites (72%). Mongoose, cats, pigs, and deer were eradicated from every site where they were targeted. Predator incursions occurred in every fence. Rat and mouse incursions were in many cases chronic or complete reinvasions, but cat and mongoose incursions were occasional and depended on fence type (i.e., enclosed vs. peninsula). The advent of predator exclusion fencing has resulted in great gains for protecting existing seabirds and waterbirds, which demonstrated dramatic increases in reproductive success and colony growth. With threats from invasive species expected to increase in the future, predator exclusion fencing will become an increasingly important tool in protecting island species.


Asunto(s)
Especies Introducidas , Islas , Animales , Hawaii , Conducta Predatoria , Conservación de los Recursos Naturales , Ecosistema , Aves
14.
PeerJ ; 12: e17510, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38952973

RESUMEN

The volcano rabbit (Romerolagus diazi) is a lagomorph endemic to the central mountains of the Trans-Mexican Volcanic Belt and is classified as threatened at extinction risk. It is a habitat specialist in bunchgrass communities. The annual wildfires that occur throughout its distribution range are a vulnerability factor for the species. However, the effects of wildfires on volcano rabbit populations are not fully understood. We evaluated the occupancy and change in the volcano rabbit relative abundance index in the burned bunchgrass communities of the Ajusco-Chichinautzin Mountain Range during an annual cycle of wildfire events. Additionally, we assessed the factors that favor and limit occupation and reoccupation by the volcano rabbit using the relative abundance index in burned plots as an indicator of these processes. The explanatory factors for the response of the volcano rabbit were its presence in the nearby unburned bunchgrasses, the height of three species of bunchgrass communities, the proportion of different types of vegetation cover within a 500 m radius around the burned plots, heterogeneity of the vegetation cover, and the extent of the wildfire. Statistical analyses indicated possible reoccupation in less than a year in burned bunchgrass communities adjacent to unburned bunchgrass communities with volcano rabbits. The relative abundance index of volcano rabbits was not favored when the maximum height of the Muhlenbergia macroura bunchgrass community was less than 0.77 m. When the vegetation around the burned plots was dominated by forest (cover >30% of the buffer) and the fire was extensive, the number of latrines decreased per month but increased when the bunchgrass and shrub cover was greater around the burned plots. While the statistical results are not conclusive, our findings indicate a direction for future projects, considering extensive monitoring to obtain a greater number of samples that contribute to consolidating the models presented.


Asunto(s)
Ecosistema , Incendios Forestales , Animales , México , Lagomorpha , Conejos , Poaceae
15.
PeerJ ; 12: e17460, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38952991

RESUMEN

A taxonomic revision of Rhizophora L. (Rhizophoraceae) in Thailand is presented. Two species, R. apiculata Blume and R. mucronata Poir., are enumerated with updated morphological descriptions, illustrations and a taxonomic identification key, together with notes on distributions, habitats and ecology, phenology, conservation assessments, etymology, vernacular names, uses, and specimens examined. Three names in Rhizophora, are lectotypified: R. apiculata and two associated synonyms of R. mucronata (i.e., R. latifolia Miq. and R. macrorrhiza Griff.). R. longissima Blanco, a synonym of R. mucronata, is neotypified. All two Rhizophora species have a conservation assessment of Least Concern (LC). Based on the morphological identification, these two species can be distinguished from one another by the shape and width of the leaf laminae and the length of a terminal stiff point of the leaf laminae; the type and position of the inflorescences and the number of flowers per inflorescence; the character and color of the bracteoles; the presence or absence of the flower pedicels; the shape of the mature flower buds; the shape, color, and texture of the sepals; the shape, character, and the presence or absence of hairs of the petals; the number of stamens per flower; the size of the fruits; the color and size of the hypocotyls; the color and diameter of the cotyledonous cylindrical tubes; and the color of the colleters and exudate. The thick cuticles, sunken stomata, large hypodermal cells, and cork warts are adaptive anatomical features of leaves in Rhizophora that live in the mangrove environments. The pollen grains of Thai Rhizophora species are tricolporate, prolate spheroidal or oblate spheroidal shapes, small-sized, and reticulate exine sculpturing.


Asunto(s)
Rhizophoraceae , Tailandia , Rhizophoraceae/anatomía & histología , Ecosistema , Hojas de la Planta/anatomía & histología
16.
Sci Rep ; 14(1): 14985, 2024 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-38951669

RESUMEN

Climate change is known to affect the distribution and composition of species, but concomitant alterations to functionally important aspects of behaviour and species-environment relations are poorly constrained. Here, we examine the ecosystem ramifications of changes in sediment-dwelling invertebrate bioturbation behaviour-a key process mediating nutrient cycling-associated with near-future environmental conditions (+ 1.5 °C, 550 ppm [pCO2]) for species from polar regions experiencing rapid rates of climate change. We find that responses to warming and acidification vary between species and lead to a reduction in intra-specific variability in behavioural trait expression that adjusts the magnitude and direction of nutrient concentrations. Our analyses also indicate that species behaviour is not predetermined, but can be dependent on local variations in environmental history that set population capacities for phenotypic plasticity. We provide evidence that certain, but subtle, aspects of inter- and intra-specific variation in behavioural trait expression, rather than the presence or proportional representation of species per se, is an important and under-appreciated determinant of benthic biogeochemical responses to climate change. Such changes in species behaviour may act as an early warning for impending ecological transitions associated with progressive climate forcing.


Asunto(s)
Cambio Climático , Invertebrados , Océanos y Mares , Animales , Invertebrados/fisiología , Ecosistema , Agua de Mar , Concentración de Iones de Hidrógeno , Calentamiento Global , Dióxido de Carbono/metabolismo
17.
BMC Ecol Evol ; 24(1): 87, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38951779

RESUMEN

Widespread species often experience significant environmental clines over the area they naturally occupy. We investigated a widespread livebearing fish, the Sailfin molly (Poecilia latipinna) combining genetic, life-history, and environmental data, asking how structured populations are. Sailfin mollies can be found in coastal freshwater and brackish habitats from roughly Tampico, Veracruz in Mexico to Wilmington, North Carolina, in the USA. In addition, they are found inland on the Florida peninsula. Using microsatellite DNA, we genotyped 168 individuals from 18 populations covering most of the natural range of the Sailfin molly. We further determined standard life-history parameters for both males and females for these populations. Finally, we measured biotic and abiotic parameters in the field. We found six distinct genetic clusters based on microsatellite data, with very strong indication of isolation by distance. However, we also found significant numbers of migrants between adjacent populations. Despite genetic structuring we did not find evidence of cryptic speciation. The genetic clusters and the migration patterns do not match paleodrainages. Life histories vary between populations but not in a way that is easy to interpret. We suggest a role of humans in migration in the sailfin molly, for example in the form of a ship channel that connects southern Texas with Louisiana which might be a conduit for fish migration.


Asunto(s)
Repeticiones de Microsatélite , Poecilia , Animales , Poecilia/genética , Repeticiones de Microsatélite/genética , Masculino , Femenino , Fenotipo , Variación Genética/genética , Ecosistema , Rasgos de la Historia de Vida
18.
Environ Monit Assess ; 196(8): 691, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38960930

RESUMEN

Urban forests face multiple human-mediated pressures leading to compromised ecosystem structure and functioning. Therefore, understanding ecosystem structure in response to ongoing pressures is crucial for sustaining ecological integrity and human well-being. We aim to assess the disturbance and its effects on the vegetation structure of urban forests in Chandigarh using a combination of remote sensing techniques and vegetation surveys. The disturbance was evaluated as a change in NDVI (Normalised Difference Vegetation Index) from 2001 to 2021 by applying the BFAST (Breaks For Additive Season and Trend) algorithm to the MODIS satellite imagery data. A vegetation survey was conducted to compare the species composition, taxonomic and phylogenetic diversity as measures of forest vegetational structure. While signals of disturbance were evident, the changes in vegetation structure were not well established from our study. Further, this analysis indicated no significant differences in vegetation composition due to disturbance (F1,12 = 0.91, p = 0.575). However, the phylogenetic diversity was substantially lower for disturbed plots than undisturbed plots, though the taxonomic diversity was similar among the disturbed and undisturbed plots. Our results confirmed that disturbance effects are more prominent on the phylogenetic than taxonomic diversity. These findings can be considered early signals of disturbance and its impact on the vegetation structure of urban forests and contribute to the knowledge base on urban ecosystems. Our study has implications for facilitating evidence-based decision-making and the development of sustainable management strategies for urban forest ecosystems.


Asunto(s)
Biodiversidad , Monitoreo del Ambiente , Bosques , Monitoreo del Ambiente/métodos , India , Ciudades , Ecosistema , Imágenes Satelitales , Tecnología de Sensores Remotos , Conservación de los Recursos Naturales , Árboles , Filogenia
19.
Environ Monit Assess ; 196(8): 696, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38963444

RESUMEN

Salinity-induced desertification is a pressing environmental issue that poses a significant threat to the sustainability of oasis ecosystems worldwide. These ecosystems are vital to the livelihoods of millions of people living in hyper-arid, arid and semi-arid regions, providing essential resources such as food, water and other necessities. However, overexploitation of natural resources, changes in land use and climate change have led to the degradation of these ecosystems, resulting in soil salinisation, waterlogging and other adverse effects. Combating salinity-induced desertification requires a comprehensive approach that addresses both the underlying causes of ecosystem degradation and the direct consequences for local communities. The strategy may include measures for sustainable land use, reforestation and water conservation. It is also essential to involve local communities in these activities and to ensure that their perspectives are heard. The aim of this article is to examine the causes and processes of salinity-induced desertification in oasis ecosystems and the implications for their sustainability. It also examines strategies that are being used to prevent desertification and promote sustainable oasis management. This article aims to raise awareness of this critical issue and to promote action towards a more sustainable future.


Asunto(s)
Cambio Climático , Conservación de los Recursos Naturales , Ecosistema , Salinidad , Monitoreo del Ambiente , Suelo/química
20.
Environ Monit Assess ; 196(8): 694, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38963575

RESUMEN

Human activities at sea can produce pressures and cumulative effects on ecosystem components that need to be monitored and assessed in a cost-effective manner. Five Horizon European projects have joined forces to collaboratively increase our knowledge and skills to monitor and assess the ocean in an innovative way, assisting managers and policy-makers in taking decisions to maintain sustainable activities at sea. Here, we present and discuss the status of some methods revised during a summer school, aiming at better management of coasts and seas. We include novel methods to monitor the coastal and ocean waters (e.g. environmental DNA, drones, imaging and artificial intelligence, climate modelling and spatial planning) and innovative tools to assess the status (e.g. cumulative impacts assessment, multiple pressures, Nested Environmental status Assessment Tool (NEAT), ecosystem services assessment or a new unifying approach). As a concluding remark, some of the most important challenges ahead are assessing the pros and cons of novel methods, comparing them with benchmark technologies and integrating these into long-standing time series for data continuity. This requires transition periods and careful planning, which can be covered through an intense collaboration of current and future European projects on marine biodiversity and ecosystem health.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Ecosistema , Monitoreo del Ambiente , Monitoreo del Ambiente/métodos , Conservación de los Recursos Naturales/métodos , Humanos , Océanos y Mares , Actividades Humanas
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