Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 6.556
Filtrar
1.
Ecol Evol ; 14(9): e70187, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39234164

RESUMO

Climate change is exerting unprecedented impacts on marine habitats, and many sessile invertebrate species, such as the endangered giant clam Tridacna maxima, are particularly sensitive to climate driven changes in their environment. Understanding its spatial distribution and conservation requirements is of crucial significance in formulating effective protection strategies. However, the species has been extensively harvested and depleted in many regions, leading to its listing as endangered species by the International Union for Conservation of Nature (IUCN). While marine protected areas (MPAs) are considered effective conservation tools, it remains uncertain whether existing MPAs adequately protect these vulnerable giant clams. To enhance the management and conservation of this species, we employed a Species Distribution Models (SDMs) approach, integrating occurrence records of T. maxima with environmental variables, to predict its potential distribution based on habitat suitability and capture spatiotemporal changes. Based on geographical and genetic variations, the T. maxima in the Indo-Pacific core region is primarily divided into two populations: the East Indian Ocean-South China Sea population (EIOS) and the West Pacific-Indonesia population (WPI). We first quantified realized niche to reveal significant differences in ecological niche space among different populations. Subsequently, SDMs were constructed at both species and population levels, demonstrating that population-level SDMs provide more reliable predictions of population distributions due to differential responses to climatic predictor variables. Finally, we conducted an assessment to identify conservation gaps for T. maxima beyond the existing MPAs and proposed recommendations for future establishment of MPAs within the current framework. Based on these findings, appropriate conservation policies have been proposed to effectively protect the habitat of different geographical populations of T. maxima. Additionally, spatiotemporal predictions of habitat suitability provide crucial information for developing adaptive management strategies for T. maxima in response to climate change, including designing new protected areas and adjusting the location and extent of existing protected areas based on their geographical distribution.

2.
Environ Res ; 262(Pt 2): 119807, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39222731

RESUMO

Dechlorane plus (DP) has been detected in a variety of environmental media and in human. Measurement of DPs in hair, urine, and house dust across different habitats allows for the assessment of short-term spatial changes in human exposure to DPs, as well as their excretion in urine. This offers a significant reference point for further research on the behavior of persistent pollutants within organisms. We measured and analyzed the concentrations of DP in the hair and urine of 32 students from a university in Beijing during school and home phases, and in indoor dust from dormitories and some home environments. The results indicated that the concentrations of DP in three types of samples were higher during the home phase compared to the school phase. We compared the fanti values and identified selective enrichment of syn-DP in hair, along with selective excretion of syn-DP in urine. Utilizing molecular docking technique, we simulated the binding effect between DP and the Megalin protein. The results demonstrated that the binding energy of anti-DP to Megalin was higher than that of syn-DP, suggesting that anti-DP has a greater propensity to bind to Megalin and be reabsorbed. This results in higher levels of syn-DP excretion in urine. Finally, we categorized students based on their participation in the organic exposure experiment and their BMI. The results indicated that the concentrations of DP in hair and urine were higher in the exposed group compared to the non-exposed group during the school year. After excluding the effect of exposure, habitat changes were more likely to affect the accumulation and excretion of DP in normal-weight students (BMI ≤24 kg/m2, n = 28), while overweight students (BMI >24 kg/m2, n = 4) were less affected by the effect of habitat because of their higher body fat percentage and their greater ability to accumulate DP.

3.
MethodsX ; 13: 102935, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39295629

RESUMO

Aerial drone imaging is an efficient tool for mapping and monitoring of coastal habitats at high spatial and temporal resolution. Specifically, drone imaging allows for time- and cost-efficient mapping covering larger areas than traditional mapping and monitoring techniques, while also providing more detailed information than those from airplanes and satellites, enabling for example to differentiate various types of coastal vegetation. Here, we present a systematic method for shallow water habitat classification based on drone imagery. The method includes:•Collection of drone images and creation of orthomosaics.•Gathering ground-truth data in the field to guide the image annotation and to validate the final map product.•Annotation of drone images into - potentially hierarchical - habitat classes and training of machine learning algorithms for habitat classification.As a case study, we present a field campaign that employed these methods to map a coastal site dominated by seagrass, seaweed and kelp, in addition to sediments and rock. Such detailed but efficient mapping and classification can aid to understand and sustainably manage ecologically and valuable marine ecosystems.

4.
Heliyon ; 10(17): e37398, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39296247

RESUMO

Degradation, fragmentation, and habitat loss significantly threaten the survival of giant pandas (Ailuropoda melanoleuca). Habitat suitability evaluations (HSEs) represent a crucial component of giant panda habitat research. However, a systematic review of HSE research on giant pandas has not been conducted in recent years. To make up for that, we synthesised HSE research on giant pandas publicated from 2013 to 2022 and conducted a comprehensive analysis of the evaluation scale, evaluation methods, and research findings. We found a correlation between the geographical distribution of giant pandas and HSE-based studies on giant pandas. Furthermore, we observed a trend towards interdisciplinary and large-scale research. Although the evaluation accuracy has improved compared to that of earlier work, some limitations still remain, such as concentrated evaluation areas, incomplete indicators, and outdated data. Current HSE research on giant pandas helps determine suitable habitat distributions, facilitating protection strategies and management planning for protected areas. We suggest that future research should prioritize those unexplored or under-evaluated areas, incorporate a broader range of microenvironmental indicators, and update data resources and methodologies. This study bridges the gap in systematic reviews on HSEs of the giant panda and provides valuable references and recommendations for future research as well as the protection and management of giant panda habitats.

5.
Sci Rep ; 14(1): 21663, 2024 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-39289429

RESUMO

Knowledge on the occurrence and behaviour of baleen whales around sub-Antarctic regions is limited, and usually based on short, seasonal sighting research from shore or research vessels and whaling records, neither of which provide accurate and comprehensive year-round perspectives of these animals' ecology. We investigated the seasonal acoustic occurrence and diel vocalizing pattern of baleen whales around the sub-Antarctic Prince Edward Islands (PEIs) using passive acoustic monitoring data from mid-2021 to mid-2023, detecting six distinct baleen whale songs from Antarctic blue whales, Madagascan pygmy blue whales, fin whales, Antarctic minke whales, humpback whales, and sei whales. Antarctic blue and fin whales were detected year-round whereas the other species' songs were detected seasonally, including a new Antarctic minke whale bio-duck song sub-type described here for the first time. Antarctic minke and sei whales were more vocally active at night-time whereas the other species had no clear diel vocalizing patterns. Random forest models identified month and/or sea surface temperature as the most important predictors of all baleen whale acoustic occurrence. These novel results highlight the PEIs as a useful habitat for baleen whales given the number of species that inhabit or transit through this region.


Assuntos
Acústica , Estações do Ano , Vocalização Animal , Baleias , Animais , Vocalização Animal/fisiologia , Regiões Antárticas , Baleias/fisiologia , Ilhas , Ecossistema
6.
PeerJ ; 12: e18035, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39314839

RESUMO

Background: Gaur (Bos gaurus) is listed as a vulnerable species in the IUCN Red List of threatened species due to the rapid population decline caused by human pressures in their habitats. To develop successful conservation plans, it is essential to understand the relationship between Gaur and their habitats. This study aimed to investigate the factors influencing Gaur habitat use and identify and rank conservation threats in Chitwan National Park, Nepal. Methods: Using line transect surveys, we recorded Gaur's presence via direct sightings and indirect signs (dung, footprints, horns) over an area of 176 km2 in July and August 2022. We used binary logistic regression models to determine the collected ecological and anthropogenic factors influencing the occurrence of Gaur and the relative whole-site threat ranking method to rank conservation threats. Results: The results revealed that the probability of Gaur occurrence increases with moderate to high canopy cover, riverine and Shorea robusta dominated forests, and nearest distance to road/path/firelines, while decreasing with the presence of predators. Uncontrolled fire, invasive species, human disturbances, and climate change were ranked as the most prevailing threats to Gaur in our study area. Conservation managers should implement effective habitat management interventions, such as construction of waterhole, firelines maintenance, grassland management, and control of invasive species in the potential habitats, to safeguard and maintain the sustainability of Gaur populations and associated herbivores. Future studies should consider larger geographical settings and multiple seasons, and habitat suitability assessments should be conducted to determine current and future suitable habitat refugia for Gaur and other threatened wildlife species at the landscape level.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Espécies em Perigo de Extinção , Parques Recreativos , Estações do Ano , Nepal , Animais , Parques Recreativos/estatística & dados numéricos , Humanos , Efeitos Antropogênicos , Mudança Climática
7.
Front Plant Sci ; 15: 1445764, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39315375

RESUMO

Clinopodium polycephalum (Vaniot) C. Y. Wu & S. J. Hsuan, a vital plant in traditional Chinese medicine, has been used for its hemostatic properties since 1220 AD. Despite its recognized medicinal benefits including anti-inflammatory and cardiovascular applications and increasing market demands, research on this plant remains limited, particularly from the perspective of plant ecology. Due to global warming and the resultant climate change, studies on the distribution and conservation of C. polycephalum are of great importance, especially when a clear trend that its habitat shifts to the north was observed. To predict the potential distribution of C. polycephalum under distinct climate situations, the MaxEnt model was used along with the ArcGIS software. As a result, an AUC value of 0.931 was achieved, indicating high predictive accuracy of the model. By analyzing 135 occurrence points and their corresponding bioclimatic factors (including precipitation), soil data, and other environmental variables (49 in total), 16 key factors including pH value and basic saturation were selected for downstream analysis. It was found that solar radiation in May, precipitation in May and April, and the lowest temperature in the coldest month are important factors influencing the growth and distribution of C. polycephalum. Compared to the current climate scenario, the future suitable habitat for C. polycephalum is expected to shift northwest, and under the SSP245-2061-2080 climate scenario, its highly suitable habitat area is projected to increase by 886,000 km2. These findings provide crucial insights into the environmental drivers of C. polycephalum distribution and aid in its preservation and sustainable use in traditional medicine. Based on the findings of this study, future research should focus on factors such as solar radiation in May and the lowest temperature in the coldest month within the suitable habitat to ensure its effective conservation.

8.
Sci Total Environ ; 954: 176373, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39299311

RESUMO

North Africa is among the most water-stressed regions in the world; still, the habitat requirements of its freshwater biota are largely unknown. In this study, (i) we developed habitat suitability curves (HSCs) for freshwater macroinvertebrates in two poorly studied, regulated North African rivers (Ziz and Oum Er-Rbia), and (ii) assessed environmental flows downstream of each river dam by incorporating the HSCs in two-dimensional ecohydraulic models. We demonstrate a low-cost sampling methodology combined with freely distributed ecohydraulic modeling software. The results showed that macroinvertebrates in the arid-desert Ziz River could tolerate a wide range of habitats in terms of flow velocity and water depth compared to the arid-steppe Oum Er-Rbia River, probably due to their adaptation to extreme (arid-desert) environmental conditions. Optimal environmental flows downstream of the Al Hassan Addakhil (Ziz River) and the Al Massira (Oum Er-Rbia River) dams were 1 m3/s and 2 m3/s, respectively. However, environmental flows at 0.5 m3/s and 1 m3/s, respectively, could still maintain sustainable freshwater biota downstream of the dams. The results further highlight the critical status of the Ziz River, which was completely dry, and the alarming status of the Oum Er-Rbia River due to the significant reduction in the water levels of the Al Massira Dam. In a continuously changing climate, we suggest that the proposed environmental flows should be immediately delivered to prevent droughts and ensure healthy freshwater communities downstream of the dams, within a basin-wide freshwater management framework. In this water scarce region, more research is necessary to increase ecological awareness about these understudied freshwater systems and achieve a balance between human needs and ecosystem requirements.

9.
Sci Total Environ ; 953: 175917, 2024 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-39218102

RESUMO

Amphibians, the most threatened vertebrates globally, face risks due to climate change, habitat loss, and fragmentation. Their sensitivity to environmental changes highlights their importance as ecological indicators. Temporary rivers, influenced by geological, climatic, and anthropogenic factors, play a critical role in shaping biodiversity and community structure. Some species of amphibians may be adapted to these temporary waters, a fact reflected in their life cycles and various biological traits. However, to develop effective conservation strategies for amphibians, it is essential to address the knowledge gaps surrounding the complex interactions between biological dynamics and fluvial habitat conditions. In this study, we investigated how trophic interactions between amphibians and other aquatic organisms (diatoms, macroinvertebrates, and fish), coupled with environmental factors (water availability and riparian structure), can affect amphibian abundance and diversity in temporary rivers. The study was conducted in a Mediterranean river network located in Sant Llorenç del Munt i l'Obac Natural Park (Catalonia, Spain). Our expectations were that habitats suitable for egg deposition, lacking predators (e.g. tadpole-predators and fish), and abundant in food sources would likely support higher amphibian abundance and diversity. However, water availability was identified as a crucial factor shaping abundance and diversity in the studied amphibian communities, even if it correlated with fish presence, and especially impacting amphibian species usually linked to permanent water bodies. Concerning biotic interactions, while our results suggested that amphibian populations in temporary rivers are more dependent on top-down than bottom-up interactions, the presence of aquatic predators was not as conclusive as expected, suggesting that in temporary rivers the fish-avoiding amphibian species can survive using microhabitats or breeding opportunities linked to natural river dynamics. Overall, our findings highlight the importance of considering multi-trophic interactions, hydroperiod and habitat heterogeneity in temporary river ecosystems for effective amphibian conservation.


Assuntos
Anfíbios , Biodiversidade , Rios , Animais , Anfíbios/fisiologia , Espanha , Ecossistema , Monitoramento Ambiental , Conservação dos Recursos Naturais , Peixes
10.
Sci Total Environ ; 953: 175794, 2024 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-39233075

RESUMO

Cephalopods occupy a mid-trophic level in marine ecosystems and are vital both ecologically and as fishery resources. However, under the pressure of climate change and fishing, the sustainability of cephalopod resources requires reasonable management. This study aims to study climate change and fishing impacts on the common economic cephalopod species habitats using species distribution models. We take the northwest Pacific Ocean region as an example, which stands out as a significant region for cephalopod production around the world. Results found that the habitats of cephalopods are moving to higher latitudes or deeper waters (Bohai Sea, mid-bottom Yellow Sea, and the Okinawa Trough waters) under climate change. Additionally, these regions are currently under lower fishing pressure, which suggests that species migration might mitigate the effects of warming and fishing. This study provides the large-scale assessment of the distribution range of cephalopods affected by climate change coping with fishing pressure in the northwest Pacific Ocean. By identifying climate refuges and key fishing grounds, we underscore the importance of this information for managing cephalopod resources in the context of climate adaptation and sustainable fishing practices.

11.
Aquat Toxicol ; 275: 107073, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39232254

RESUMO

Habitat selection by aquatic organisms is dependent on the availability of adequate conditions to support life and the benefits that the habitat provides. Contaminated environments tend to be less attractive to organisms because reduced habitat quality leads to increased maintenance costs. Consequently, reduced colonization of such disturbed habitats is an expected response. However, colonization has been understudied as an ecotoxicological test endpoint, despite its proven ability to assess habitat selection by populations across various taxa. The aim of the present study was to investigate whether previous exposure to copper could alter the colonization behavior of the freshwater prawn Macrobrachium rosenbergii along a non-forced exposure gradient of interconnected copper-contaminated habitats (0 to 500 µg/L) due to physiological and behavioral impairments. To assess this, post-larvae of M. rosenbergii were pre-exposed to 0, 50, 250 and 500 µg/L copper for a maximum period of 48 h. The physiological status and motility of the organisms after pre-exposure to copper were evaluated using behavioral endpoints (swimming activity by video tracking) and biochemical biomarkers (biotransformation, oxidative stress and neurotoxicity). The results indicated that pre-exposure to copper (at concentrations of 0, 50 and 500 µg/L) significantly influenced the median colonization concentration (CC50), which decreased from 270 µg/L to 109 µg/L. None of the assessed swimming parameters (speed, motility rate, exploration rate, and total distance) were affected by the pre-exposure to copper (0, 50 and 250 µg/L). Biochemically, cholinesterase levels were only affected in the prawn population exposed to 250 µg/L of copper. The present study provides a better understanding of the relevance of colonization as an ecotoxicological endpoint for assessing the spatial distribution of populations, including both new inhabitants and previously exposed organisms, in recovering habitats.


Assuntos
Comportamento Animal , Cobre , Ecossistema , Palaemonidae , Poluentes Químicos da Água , Animais , Palaemonidae/efeitos dos fármacos , Palaemonidae/fisiologia , Cobre/toxicidade , Poluentes Químicos da Água/toxicidade , Comportamento Animal/efeitos dos fármacos , Biomarcadores , Estresse Oxidativo/efeitos dos fármacos
12.
Int J Mol Sci ; 25(17)2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39273114

RESUMO

Staphylococcus aureus acts both as a colonizing commensal bacterium and invasive pathogen. Nasal colonization is associated with an increased risk of infection caused by the identical strain. In patients with atopic dermatitis (AD), the degree of S. aureus colonization is associated with the severity of the disease. Here, we comparatively analyzed the in vivo transcriptional profile of S. aureus colonizing the nose and non-diseased skin (non-lesional skin) as opposed to the diseased skin (lesional skin-defined here as infection) of 12 patients with AD. The transcriptional profile during the asymptomatic colonization of the nose closely resembled that of the lesional skin samples for many of the genes studied, with an elevated expression of the genes encoding adhesion-related proteins and proteases. In addition, the genes that modify and remodel the cell wall and encode proteins that facilitate immune evasion showed increased transcriptional activity. Notably, in a subgroup of patients, the global virulence regulator Agr (accessory gene regulator) and downstream target genes were inactive during nasal colonization but upregulated in the lesional and non-lesional skin samples. Taken together, our results demonstrate a colonization-like transcriptional profile on diseased skin and suggest a role for the peptide quorum sensing system Agr during the transition from asymptomatic nasal colonization to skin colonization/infection.


Assuntos
Dermatite Atópica , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Pele , Infecções Estafilocócicas , Staphylococcus aureus , Dermatite Atópica/microbiologia , Dermatite Atópica/genética , Humanos , Staphylococcus aureus/genética , Pele/microbiologia , Pele/metabolismo , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/genética , Feminino , Masculino , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Adulto , Transcriptoma , Infecções Cutâneas Estafilocócicas/microbiologia , Infecções Cutâneas Estafilocócicas/genética , Mucosa Nasal/microbiologia , Transativadores
13.
Sci Rep ; 14(1): 20973, 2024 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-39251699

RESUMO

Migratory shorebirds are one of the fastest declining groups of North American avifauna. Yet, relatively little is known about how these species select habitat during migration. We explored the habitat selection of Buff-breasted Sandpipers (Calidris subruficollis) during spring and fall migration through the Texas Coastal Plain, a major stopover region for this species. Using tracking data from 118 birds compiled over 4 years, we found Buff-breasted Sandpipers selected intensively managed crops such as sod and short-stature crop fields, but generally avoided rangeland and areas near trees and shrubs. This work supports prior studies that also indicate the importance of short-stature vegetation for this species. Use of sod and corn varied by season, with birds preferring sod in spring, and avoiding corn when it is tall, but selecting for corn in fall after harvest. This dependence on cropland in the Texas Coastal Plain is contrary to habitat use observed in other parts of their non-breeding range, where rangelands are used extensively. The species' almost complete reliance on a highly specialized crop, sod, at this critical stopover site raises concerns about potential exposure to contaminants as well as questions about whether current management practices are providing suitable conditions for migratory grassland birds.


Assuntos
Migração Animal , Ecossistema , Estações do Ano , Animais , Migração Animal/fisiologia , Texas , Pradaria , Charadriiformes/fisiologia , Fazendas , Aves/fisiologia , Zea mays
14.
Sci Rep ; 14(1): 21019, 2024 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-39251815

RESUMO

The neighborhood effect has become an important framework with which to study the mechanisms that maintain the coexistence of tree species. Phylogenetic relatedness among neighboring plants directly affects species coexistence and the maintenance of tree diversity. And some studies have reported that seedling performance is negatively correlated with phylogenetic relatedness, which termed phylogenetic negative density dependence. Soil-borne fungal pathogens affected seedling performance of phylogenetically related host species, i.e., phylogenetic Janzen-Connell effect. Seedlings may be particularly vulnerable to habitat and neighbor characteristics. Although previous studies have demonstrated the influence of neighborhood effects, phylogenetic relatedness, and habitat filtering on seedling survival, growth, and mortality, the effect of variation in these factors on seedling abundance remains unclear. To address this question, we used a 4-ha (200 m × 200 m) and monitored four-year (2020-2023) seedling dataset from a mid-montane humid evergreen broad-leaved subtropical forest in the Gaoligong Mountains, Yunnan, Southwestern China, and which consisted of 916 seedlings belonging to 56 species. The results of generalized linear mixed models showed no significant effect of conspecific adult neighbors on seedling abundance at any of the intervals evaluated. In contrast, we found evidence of phylogenetic distance density dependence in the forests of the Gaoligong Mountains. Specifically, there was a significant positive effect of the relative average phylogenetic distance between heterospecific adult neighbors and focal seedlings on focal seedling abundance in 2020; however, the relative average phylogenetic distance between heterospecific seedling neighbors and focal seedlings had a significant negative effect on seedling abundance over the four-year period (2020-2023). Among the habitat factors, only light (canopy opening) had a negative effect on seedling abundance in all four years. Light resources may be a limiting factor for seedlings, and determine seedling dynamics in subtropical forests. Overall, our results demonstrated that phylogenetic density dependence and habitat filtering affected subtropical seedling abundance. Our findings provide new evidence of the impact of phylogenetic density dependence on seedling abundance in a subtropical mid-montane humid evergreen broad-leaved forest and highlight the need to incorporate the neighborhood effect, phylogenetic relatedness, and habitat factors in models assessing seedling abundance.


Assuntos
Ecossistema , Florestas , Filogenia , Plântula , Plântula/crescimento & desenvolvimento , China , Árvores/crescimento & desenvolvimento , Biodiversidade
15.
Mar Environ Res ; 202: 106738, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39265327

RESUMO

Seismic activity, erosion, sedimentation, and extreme temperatures can cause compounding large-scale disturbances to marine organisms, like large intertidal foundational seaweeds. In November 2016, a 7.8 Mw earthquake uplifted 130 km of coastline by 0.5-6 m near Kaikoura, New Zealand and thereby increased intertidal desiccation, aerial temperatures, reef erosion, and water turbidity. Furthermore, stress on uplifted intertidal species was compounded by unprecedented marine heatwaves over the summer of 2017/18. Here we documented altered dominances of large foundational seaweed and possible flow-on effects on seaweed-associated flora and fauna, following the uplift and heatwaves. These compounding disturbances caused instant high canopy loss of the dominant primary foundation species - the large perennial canopy-forming southern bull kelp Durvillaea antarctica - and no post-disturbance recovery, suggesting a maintenance threshold has been exceeded. After canopy loss of the primary foundation species, alternative foundation species - i.e., subordinate competitors under pre-disturbance conditions (the perennial canopy-forming fucoids Carpophyllum maschalocarpum, Cystophora scalaris, and Hormosira banksii) increased in abundance. Furthermore, field observations of attachment interaction networks demonstrated that the primary and alternative foundation species facilitated different sessile and mobile taxa. For example, the smaller and more morphologically complex C. maschalocarpum, H. banksii, and C. scalaris, supported more novel attachment associations, whereas the larger Durvillaea supported longer attachment chains. Overall, our results highlight abrupt and potentially long-lasting ecological changes after compounding disturbances, which altered dominance hierarchies. Alternative foundation species are now more common than the pre-disturbance primary foundation species, with flow-on effects on wider communities that depend on biogenic habitats.

16.
Sci Rep ; 14(1): 21149, 2024 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-39256435

RESUMO

Freshwater turtles are often used as terrarium pets, especially juveniles of exotic species. At the adult stage they are often released by their owners into the wild despite their high invasion potential. In Europe these thermophilic potentially invasive alien species occupy the habitats of the native European pond turtle Emys orbicularis (Linnaeus, 1758), with new records from the wild being made specifically in Eastern Europe (Latvia and Ukraine) during recent decades. Assessing the potential of alien freshwater turtles to establish in new territories is of great concern for preventing invasion risks while preserving native biodiversity in the present context of climate change. We explored this issue by identifying the present and future (by 2050) suitable habitats of the European pond turtle and several potentially invasive alien species of freshwater turtle already settled in Europe, using a geographic information system (GIS) modelling approach based on datasets from CliMond for climate, Near-global environmental information (NGEI) for freshwater ecosystems (EarthEnv) and Maxent modelling using open-access databases, data from the literature and original field data. Modelling was performed for seven species of alien freshwater turtles occurring from the extreme northern to southern borders of the European range of E. orbicularis: the pond slider Trachemys scripta (Thunberg and Schoepff, 1792), the river cooter Pseudemys concinna (Le Conte, 1830), the Florida red-bellied cooter Pseudemys nelsoni (Carr, 1938), the false map turtle Graptemys pseudogeographica (Gray, 1831), the Chinese softshell turtle Pelodiscus sinensis (Wiegmann, 1835), the Caspian turtle Mauremys caspica (Gmelin, 1774) and the Balkan terrapin Mauremys rivulata (Valenciennes, 1833). In Ukraine, the most Eastern limit of E. orbicularis distribution, were previously reported northern American originated T. scripta, M. rivulata, M. caspica, whereas in Latvia, Emys' most northern limit, were additionally reported P. concinna, P. nelsoni, G. pseudogeographica and Asia originated P. sinensis. The resulting Species Distribution Models (SDM) were of excellent performance (AUC > 0.8). Of these alien species, the most potentially successful in terms of range expansion throughout Europe were T. scripta (34.3% of potential range expansion), G. pseudogeographica (24.1%), and M. caspica (8.9%) and M. rivulata (4.3%) mainly in Eastern Europe, especially in the south of Ukraine (Odesa, Kherson, Zaporizhzhia regions, and Crimean Peninsula). Correlation between the built SDMs for the native E. orbicularis and the invasive alien T. scripta was reliably high, confirming the highly likely competition between these two species in places they cooccur. Moreover, a Multiple Regression Analysis revealed that by 2050, in most of Europe (from the western countries to Ukraine), the territory overlap between E. orbicularis and potentially invasive alien species of freshwater turtles will increase by 1.2 times, confirming higher competition in the future. Importantly, by 2050, Eastern Europe and Ukraine are predicted to be the areas with most suitable habitats for the European pond turtle yet with most limited overlap with the invasive alien species. We conclude that Eastern Europe and Ukraine are the most relevant priority conservation areas for the European pond turtle where it is now necessary to take protective measures to ensure safe habitat for this native species on the long-term.


Assuntos
Ecossistema , Água Doce , Espécies Introduzidas , Tartarugas , Animais , Tartarugas/fisiologia , Europa Oriental , Mudança Climática , Biodiversidade , Lagoas , Europa (Continente) , Distribuição Animal
17.
Mar Environ Res ; 202: 106740, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39255629

RESUMO

Critical loss of habitat is the greatest threat to biodiversity, yet some species are inherently plastic to and may even benefit from changes in ecosystem states. The crown-of-thorns sea star (CoTS; Acanthaster spp.) may be one such organism. CoTS are large corallivores native to the tropical Indo-Pacific and in unexplained high densities, can adversely affect entire coral reefs. Proximal causes of CoTS outbreaks remain elusive, so this phenomenon remains a daunting and costly challenge for reef conservation and management. Amplifying anthropogenic impacts and new empirical data point to the degraded reef hypothesis to explain the episodic nature of CoTS population outbreaks. We posit that loss of live coral paradoxically benefits CoTS juveniles, which accumulate in their rubble nursery habitat before conditions trigger their pulsed emergence as coral-eaters. We review trait plasticity across the CoTS life cycle and present the degraded reef hypothesis in an integrative understanding of their propensity to outbreak.

18.
Glob Chang Biol ; 30(9): e17513, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39319475

RESUMO

Human activities and climate change have accelerated species losses and degradation of ecosystems to unprecedented levels. Both theoretical and empirical evidence suggest that extinction cascades contribute substantially to global species loss. The effects of extinction cascades can ripple across levels of ecological organization, causing not only the secondary loss of taxonomic diversity but also functional diversity erosion. Here, we take a step forward in coextinction analysis by estimating the functional robustness of reef fish communities to species loss. We built a tripartite network with nodes and links based on a model output predicting reef fish occupancy (113 species) as a function of coral and turf algae cover in Southwestern Atlantic reefs. This network comprised coral species, coral-associated fish (site occupancy directly related to coral cover), and co-occurring fish (occupancy indirectly related to coral cover). We used attack-tolerance curves and estimated network robustness (R) to quantify the cascading loss of reef fish taxonomic and functional diversity along three scenarios of coral species loss: degree centrality (removing first corals with more coral-associated fish), bleaching vulnerability and post-bleaching mortality (most vulnerable removed first), and random removal. Degree centrality produced the greatest losses (lowest R) in comparison with other scenarios. In this scenario, while functional diversity was robust to the direct loss of coral-associated fish (R = 0.85), the taxonomic diversity was not robust to coral loss (R = 0.54). Both taxonomic and functional diversity showed low robustness to indirect fish extinctions (R = 0.31 and R = 0.57, respectively). Projections of 100% coral species loss caused a reduction of 69% of the regional trait space area. The effects of coral loss in Southwestern Atlantic reefs went beyond the direct coral-fish relationships. Ever-growing human impacts on reef ecosystems can cause extinction cascades with detrimental consequences for fish assemblages that benefit from corals.


Assuntos
Biodiversidade , Mudança Climática , Recifes de Corais , Extinção Biológica , Peixes , Animais , Peixes/fisiologia , Antozoários/fisiologia
19.
Landsc Ecol ; 39(9): 174, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39247152

RESUMO

Context: There has been a limited amount of research which comparatively examines the local and landscape scale ecological determinants of the community structure of both riparian and aquatic bird communities in floodplain ecosystems. Objectives: Here, we quantified the contribution of local habitat structure, land cover and spatial configuration of the sampling sites to the taxonomical and functional structuring of aquatic and terrestrial bird communities in a relatively intact floodplain of the river Danube, Hungary. Methods: We used the relative abundance of species and foraging guilds as response variables in partial redundancy analyses to determine the relative importance of each variable group. Results: Local-scale characteristics of the water bodies proved to be less influential than land cover and spatial variables both for aquatic and terrestrial birds and both for taxonomic and foraging guild structures. Purely spatial variables were important determinants, besides purely environmental and the shared proportion of variation explained by environmental and spatial variables. The predictability of community structuring generally increased towards the lowest land cover measurement scales (i.e., 500, 250 or 125 m radius buffers). Different land cover types contributed at each scale, and their importance depended on aquatic vs terrestrial communities. Conclusions: These results indicate the relatively strong response of floodplain bird communities to land cover and spatial configuration. They also suggest that dispersal dynamics and mass-effect mechanisms are critically important for understanding the structuring of floodplain bird communities, and should therefore be considered by conservation management strategies. Supplementary Information: The online version contains supplementary material available at 10.1007/s10980-024-01948-3.

20.
Environ Evid ; 13(1): 12, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-39294693

RESUMO

BACKGROUND: Shallow, tropical coral reefs face compounding threats from climate change, habitat degradation due to coastal development and pollution, impacts from storms and sea-level rise, and pulse disturbances like blast fishing, mining, dredging, and ship groundings that reduce reef height and complexity. One approach toward restoring coral reef physical structure from such impacts is deploying built structures of artificial, natural, or hybrid (both artificial and natural) origin. Built structures range from designed modules and repurposed materials to underwater sculptures and intentionally placed natural rocks. Restoration practitioners and coastal managers increasingly consider incorporating - and in many cases have already begun to incorporate - built structures into coral reef-related applications, yet synthesized evidence on the ecological (coral-related; e.g., coral growth, coral survival) and physical performance of built structures in coral ecosystems across a variety of contexts (e.g., restoration, coastal protection, mitigation, tourism) is not readily available to guide decisions. To help fill this gap and inform management decisions, we systematically mapped the global distribution and abundance of published evidence on the ecological (coral-related) and physical performance of built structure interventions in shallow (≤ 30 m), tropical (35°N to 35°S) coral ecosystems. METHODS: To identify potentially relevant articles, we used predefined and tested strategies to search two indexing platforms, one bibliographic database, two open discovery citation indexes, one web-based search engine, one novel literature discovery tool, 19 organizational websites, and information requested from stakeholders. Discovered articles were screened according to preset eligibility criteria first by title and abstract and second by full text. Articles included during full text screening were coded to extract metadata following a predefined framework. We analyzed and visualized the evidence base to answer our primary and secondary research questions and to identify knowledge clusters and gaps. Findings are reported in a narrative synthesis. RESULTS: Our search discovered > 20,000 potentially relevant unique articles, of which 258 were included in the systematic map. The evidence base spans 50 countries, and the volume of evidence increased over the past five decades. Built structures were most commonly installed for coral restoration (61%) or coastal protection (12%). Structures were predominately characterized as artificial (87%), with fewer hybrid or natural interventions. Evidence clusters existed for intentionally designed artificial structures and outcomes associated with coral-related ecological performance, including coral mortality, growth, recruitment, cover, and diversity. Pronounced evidence gaps occurred at the intersection of several ecological coral-related performance outcomes (e.g., connectivity, microbiome) across all types of built structures; gaps also existed across most ecological coral-related outcomes for artwork and repurposed artificial structures. Physical performance of built structures was most frequently evaluated for outcomes related to waves (n = 14) and sediment and morphology (n = 11) with pervasive evidence gaps across other outcomes like storm surge and water level. CONCLUSIONS: While the systematic map highlighted several evidence clusters, it also revealed pronounced evidence gaps surrounding the coral-related ecological and physical performance of built structures in coral ecosystems. The compiled evidence base will help inform policy, management, and future consideration of built structures in reef-related applications, including habitat restoration, environmental mitigation, and coastal protection. Map findings also point to promising future research avenues, such as investigating seascape-scale ecological effects of and the physical performance of built structures.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA