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1.
J Med Primatol ; 53(4): e12720, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38958239

RESUMO

BACKGROUND: Hematologic and blood biochemical values are key tools for assessing primate health. A long-term behavioral study of howler monkeys at a single site (La Pacífica, Guanacaste, Costa Rica), afforded the opportunity to develop baseline values for a large group of animals, evaluating differences between adult males and females and comparing to a report in the same population two decades later. METHODS: In 1998, 64 free-ranging mantled howler monkeys were anesthetized and sampled for hematologic and biochemical analysis. RESULTS: Blood analysis is reported for 29 adult females, 9 juvenile females, 19 adult males and 3 juvenile males. Four adults were excluded due to external injury or disease. There were few significant differences between adult females, juvenile females, and adult males. CONCLUSIONS: Baseline blood parameters are useful for determining normal values for howler monkey populations. The values for total protein, blood urea nitrogen, glucose, liver enzymes and potassium differed from a later study in 2019 may indicate changes that are influencing howler monkey health.


Assuntos
Alouatta , Análise Química do Sangue , Animais , Alouatta/sangue , Alouatta/fisiologia , Costa Rica , Feminino , Masculino , Análise Química do Sangue/veterinária , Testes Hematológicos/veterinária , Valores de Referência
2.
Sci Total Environ ; : 174570, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38977105

RESUMO

Marine community composition is expected to be relatively stable in a natural environment over time but shift under increasing anthropogenic disturbances. In coastal waters, diatoms and dinoflagellates are two dominant phytoplankton functional groups. In this study, we developed an areal phytoplankton community composition index (APCI) that is based on the area of a scatter plot of dinoflagellate abundance (y-axis) vs diatom abundance (x-axis) using a time window of 1 year, 2 years or 3 years data. An APCI allows an ecological interpretation: it represents the fluctuability of a community composition within a time window and a temporal change between two neighbouring APCIs in a time series represents the stability of the composition. We used a 28-yr time series of monthly data on diatom and dinoflagellate abundance at four stations in Tolo Harbour and Channel (Tolo), Hong Kong to test the hypothesis that temporal changes in APCIs indicate environmental disturbances and to examine the applicability of APCI to indicate changes in nutrient conditions. We calculated the area (APCI) of a scatter plot of monthly data for 1-year, 2-year and 3-year windows, referred to as APCI-1y, -2y and -3y, respectively. The results show that, the fluctuability, is larger in APCI-3y than in APCI-1y, while the stability is stronger as temporal changes between neighbouring APCI-3y are smaller than between APCI-1ys. Temporal trends of APCIs are significantly correlated with those of dissolved inorganic nitrogen and phosphate concentration, which have declined after the implementation of a sewage diversion management plan in 1998. Hence, the APCI method is likely a robust indicator to assess a response of the phytoplankton community composition in a water body to environmental disturbances.

3.
J Environ Manage ; 364: 121371, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38879965

RESUMO

Rapid urbanization and high-intensity socio-economic activities in China have caused severe ecological problems. Implementing ecological restoration in China has become an inevitable way to restore the ecosystem. Ecosystem health is crucial for evaluating ecological conditions and trends, but comprehensive national studies that use quantitative ecosystem health assessments to guide specific ecological restoration are lacking. This study constructs the Vigor-Organization-Resilience-Services (VORS) model to evaluate the ecosystem health level of China during 2000-2020. Then, through the natural breakpoint and intelligent clustering correction, we carried out the ecological restoration zoning and proposed corresponding measures. The results show that China's overall ecosystem health declined from 2000 to 2020, and ecological restoration is imminent. The spatial pattern of ecosystem health is generally favorable in the south and usually poor in the north. China protects poor ecosystems' health well but needs more for better ones. To combat this degradation, we propose a zoning strategy that classifies the landscape into five categories: Ecosystem Conservation Areas (3.47%), focusing on biodiversity preservation; Ecosystem Enhancement Areas (10.53%), aiming at increasing ecological resilience; Ecosystem Buffer Zones (23.04%), intending to mitigate human impacts; Ecosystem Correction Zones (33.79%), targeting at restoring degraded ecosystems; and Ecosystem Reshaping Zones (29.17%), designing to revitalize ecological functions. The ecological restoration zoning in China proposed in this study, combined with appropriate and practical restoration tools, will help mitigate ecological problems and improve stability and ecosystem health.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , China , Biodiversidade , Urbanização , Ecologia , Humanos
4.
Philos Trans R Soc Lond B Biol Sci ; 379(1904): 20230101, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38705179

RESUMO

Insects are the most diverse group of animals on Earth, yet our knowledge of their diversity, ecology and population trends remains abysmally poor. Four major technological approaches are coming to fruition for use in insect monitoring and ecological research-molecular methods, computer vision, autonomous acoustic monitoring and radar-based remote sensing-each of which has seen major advances over the past years. Together, they have the potential to revolutionize insect ecology, and to make all-taxa, fine-grained insect monitoring feasible across the globe. So far, advances within and among technologies have largely taken place in isolation, and parallel efforts among projects have led to redundancy and a methodological sprawl; yet, given the commonalities in their goals and approaches, increased collaboration among projects and integration across technologies could provide unprecedented improvements in taxonomic and spatio-temporal resolution and coverage. This theme issue showcases recent developments and state-of-the-art applications of these technologies, and outlines the way forward regarding data processing, cost-effectiveness, meaningful trend analysis, technological integration and open data requirements. Together, these papers set the stage for the future of automated insect monitoring. This article is part of the theme issue 'Towards a toolkit for global insect biodiversity monitoring'.


Assuntos
Biodiversidade , Insetos , Insetos/fisiologia , Animais , Tecnologia de Sensoriamento Remoto/métodos , Tecnologia de Sensoriamento Remoto/instrumentação , Monitoramento Biológico/métodos
5.
Heliyon ; 10(7): e27864, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38560251

RESUMO

Terrestrial ecosystems such as coniferous forests in Central Europe are experiencing changes in health status following extreme droughts compounding with severe heat waves. The increasing temporal resolution and spatial coverage of earth observation data offer new opportunities to assess these dynamics. Dense time-series of optical satellite data allow for computing Dynamic Habitat Indices (DHIs), which have been predominantly used in biodiversity studies. However, DHIs cover three aspects of vegetation changes that could be affected by drought: annual productivity, minimum cover, and seasonality. Here, we evaluate the health status of coniferous forests in the federal state of Hesse in Germany over the period 2017-2020 including the severe drought year of 2018 using DHIs based on the Normalized Difference Vegetation Index (NDVI) for drought assessment. To identify the most important variables affecting coniferous forest die-off, a series of environmental variables together with the three DHIs components were used in a logistic regression (LR) model. Each DHI component changed significantly across non-damaged and damaged sites in all years (p-value 0.05). When comparing 2017 to 2019, DHI-based annual productivity decreased and seasonality increased. Most importantly, none of the DHI components had reached pre-drought conditions, which likely indicates a change in ecosystem functioning. We also identified spatially explicit areas highly affected by drought. The LR model revealed that in addition to common environmental parameters related to temperature, precipitation, and elevation, DHI components were the most important factors explaining the health status. Our analysis demonstrates the potential of DHIs to capture the effect of drought events on Central European coniferous forest ecosystems. Since the spaceborne data are available at the global level, this approach can be applied to track the dynamics of ecosystem conditions in other regions, at larger spatial scales, and for other Land Use/Land Cover types.

6.
Heliyon ; 10(7): e28018, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38596140

RESUMO

Increasing human activities in coastal areas of Ghana have led to the degradation of many surface waterbodies, with significant consequences for the ecosystems in the affected areas. Thus, this degradation extremely affects the health of ecosystems and disrupts the essential services they provide. The present study explored the use of benthic macroinvertebrates as an indicator of estuarine degradation along the coast of Ghana. Water and sediment samples were collected bimonthly from Ankobra, Kakum and Volta estuaries for physicochemical parameters, nutrients and benthic macroinvertebrates. The findings revealed the dominance of pollution-tolerant taxa such as Capitella sp., Nereis sp., Heteromastus sp., Tubifex sp., Cossura sp. and Chironomous sp. in Kakum Estuary while pollution-sensitive taxa such as Scoloplos sp., Euridice sp., Lumbriconereis sp. and Pachymelania sp. in the Volta Estuary. The species-environment interactions showed dissolved oxygen, temperature, salinity, orthophosphate, nitrates, ammonium, electrical conductivity, turbidity, and chemical oxygen demand as the most significant parameters that complement the use of benthic macroinvertebrates as indicators of environmental quality in the studied estuaries. There were correlations of some benthic macroinvertebrate taxa with environmental factors in the estuaries suggesting low, moderate and high levels of pollution in the Volta, Kakum and Ankobra estuaries, respectively. Nevertheless, the study finds Kakum Estuary to be the ecologically healthiest estuary than the Volta and Ankobra Estuaries. Therefore, the study has shown benthic macroinvertebrates as a key indicator of ecosystem health alterations, and it is recommended that they should be incorporated with other environmental data for pollution monitoring in Ghanaian coastal waters.

7.
Sci Rep ; 14(1): 8455, 2024 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605157

RESUMO

Urban ecosystem health is the foundation of sustainable urban development. It is important to know the health status of urban ecosystem and its influencing factors for formulating scientific urban development planning. Taking Zibo city as the study area, the indicators were selected from five aspects: ecosystem vigor, structure, resilience, service function and population health to establish an assessment index system of urban ecosystem health. The health level of urban ecosystem was assessed, and its changing trend was analyzed from 2006 to 2018 in Zibo. Furthermore, obstacle degree analysis and sensitivity analysis were used to quantitatively analyze the main obstacle factors and sensitivity factors affecting urban ecosystem health, so as to provide references for improving urban ecosystem health. The results showed that the health level of urban ecosystem in Zibo showed an upward trend from 2006 to 2018. The poor structure and ecological environment quality were the main obstacle factors to urban ecosystem health. The impact of changes in a single indicator on urban ecosystem health gradually decreased, but the sensitivity index of indicators had obvious differences. Urban ecosystem health was sensitive to changes in ecosystem structure and resilience. In the future, Zibo should strengthen ecological construction, optimize the industrial structure, and develop green economy to promote urban ecosystem healthy.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Cidades , Saúde da População Urbana , China
8.
Front Environ Sci ; 12: 1-19, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38516348

RESUMO

Continued large-scale public investment in declining ecosystems depends on demonstrations of "success". While the public conception of "success" often focuses on restoration to a pre-disturbance condition, the scientific community is more likely to measure success in terms of improved ecosystem health. Using a combination of literature review, workshops and expert solicitation we propose a generalized framework to improve ecosystem health in highly altered river basins by reducing ecosystem stressors, enhancing ecosystem processes and increasing ecosystem resilience. We illustrate the use of this framework in the Mississippi-Atchafalaya River Basin (MARB) of the central United States (U.S.), by (i) identifying key stressors related to human activities, and (ii) creating a conceptual ecosystem model relating those stressors to effects on ecosystem structure and processes. As a result of our analysis, we identify a set of landscape-level indicators of ecosystem health, emphasizing leading indicators of stressor removal (e.g., reduced anthropogenic nutrient inputs), increased ecosystem function (e.g., increased water storage in the landscape) and increased resilience (e.g., changes in the percentage of perennial vegetative cover). We suggest that by including these indicators, along with lagging indicators such as direct measurements of water quality, stakeholders will be better able to assess the effectiveness of management actions. For example, if both leading and lagging indicators show improvement over time, then management actions are on track to attain desired ecosystem condition. If, however, leading indicators are not improving or even declining, then fundamental challenges to ecosystem health remain to be addressed and failure to address these will ultimately lead to declines in lagging indicators such as water quality. Although our model and indicators are specific to the MARB, we believe that the generalized framework and the process of model and indicator development will be valuable in an array of altered river basins.

9.
Chemosphere ; 355: 141679, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38527632

RESUMO

Due to its low cost, its ease of use and to the "mild action" declared for long time by the Control and Approval Agencies towards it, the herbicide Glyphosate, is one of the currently best-selling and most-used agricultural products worldwide. In this work, we evaluated the presence and spread of Glyphosate in the Po River Basin (Northern Italy), one of the regions with the most intensified agriculture in Europe and where, by now for decades, a strong and general loss of aquatic biodiversity is observed. In order to carry out a more precise study of the real presence of this herbicide in the waters, samples were collected from the minor water network for two consecutive years, starting in 2022, at an interval time coinciding with those of the spring and summer crop treatments. In contrast to the sampling strategies generally adopted by Environmental Protection Agencies, a more focused sampling strategy was adopted to highlight the possible high concentrations in minor watercourses in direct contact with cultivated fields. Finally, we investigated the possible consequences that the higher amounts of Glyphosate found in our monitoring activities can have on stress reactions in plant (Groenlandia densa) and animal (Daphnia magna) In all the monitoring campaigns we detected exceeding European Environmental Quality Standard - EQS limits (0.1 µg/L) values. Furthermore, in some intensively agricultural areas, concentrations reached hundreds of µg/L, with the highest peaks during spring. In G. densa and D. magna, the exposition to increasing doses of herbicide showed a clear response linked to metabolic stress. Overall, our results highlight how, after several decades of its use, the Glyphosate use efficiency is still too low, leading to economic losses for the farm and to strong impacts on ecosystem health. Current EU policy indications call for an agroecological approach necessary to find alternatives to chemical weed control, which farms can develop in different contexts in order to achieve the sustainability goals set by the Farm to Fork strategy.


Assuntos
Herbicidas , Poluentes Químicos da Água , Animais , Glifosato , Ecossistema , Glicina , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Herbicidas/análise
10.
Environ Geochem Health ; 46(4): 137, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483759

RESUMO

Lacustrine sediment quality indicates the effects of both natural and anthropogenic activities on the ecosystem and communities. Despite its ecological importance, myriad complexities, and potential contaminant sources, the spatial distribution of surficial sediments in Lake Victoria's Winam Gulf has never been comprehensively documented. The purpose of this study was to assess the spatial distribution, pathways, and ecological risk of metal elements in the lake using a sediment matrix. Sediment samples were collected throughout the gulf in November 2022. The concentrations of Al, As, Cd, Co, Cr, Cu, Fe, K, Mn, Mo, Ni, P, Pb, Sb, Sn, Ti, Tl, U, and Zn were compared to different contamination metrics and ecological risk assessment indices. The average concentrations were in the following decreasing order: Zn > > > Cr > > Cu > Ni > Pb > Co > As > Cd with mean (± SD) of 185 ± 45 mg kg-1, 56 ± 15 mg kg-1, 45 ± 16 mg kg-1, 37 ± 11 mg kg-1, 24 ± 5 mg kg-1, 20 ± 7 mg kg-1, 3.9 ± 1.3 mg kg-1, 0.30 ± 0.09 mg kg-1, respectively, with strong indications of anthropogenic sources. Average concentrations were in the following decreasing order: Zn > > > Cr, Cu, Ni, Pb, Co, As, and Cd levels (mean ± SD) were 185 ± 45 mg kg-1, 56 ± 15 mg kg-1, 45 ± 16 mg kg-1, 37 ± 11 mg kg-1, 24 ± 5 mg kg-1, 20 ± 7 mg kg-1, 3.9 ± 1.3 mg kg-1 and 0.30 ± 0.09 mg kg-1 with strong indications of anthropogenic sources. The geo-accumulation index (Igeo) and enrichment factor categorisation schemes, respectively, classified these as uncontaminated (level 0) and depletion to minimal enrichment (level 1), while the ecological risk analysis classified them as "low risk". The mouth of the Nyando River, as well as Kisumu, Kendu, and Homa bays, were the most element-enriched and should be prioritised for focused monitoring and remediation. As a result, targeted land management of urban, industrial, transportation, and agricultural areas offers the opportunity to reduce sediment inputs into the lake ecosystem.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Metais Pesados/análise , Ecossistema , Cádmio/análise , Lagos , Quênia , Chumbo/análise , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Sedimentos Geológicos/análise , Medição de Risco , China
11.
Sci Total Environ ; 921: 171147, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38395169

RESUMO

Numerous cities are currently grappling with the challenge of ecological transformation, especially those categorized as resource-exhausted cities. In these urban areas, land use change is a highly scrutinized issue, as different land use strategies can lead to varied outcomes, impacting the ecological environment in multiple dimensions. Assessing ecosystem health reflects the quality of the regional ecological environment and serves as a comprehensive indicator for evaluating the sustainability and stability of urban ecosystems. To this end, a multi-objective optimization model was constructed to predict land use changes under four future development scenarios (four ecological transformation modes), using Shizuishan City (China), a resource-exhausted city situated in an ecologically fragile area, as an example. The "vigor-organization-resilience" assessment framework was employed to evaluate the ecosystem health conditions in each scenario from three dimensions. The study results showed: (1) The ranking of the average ecological health levels in Shizuishan City for 2022 and different future development scenarios is as follows: Low-Carbon Economic Development Scenario (0.302) > Ecological-Economic Coordinated Development Scenario (0.291) > Baseline Scenario (0.290) > Economic Development Scenario (0.281) > 2022 (0.248). (2) Compared to 2022, the ecosystem health levels under the four ecological transformation modes had all improved, with improvement areas accounting for over 60 %, highlighting the urgent necessity of ecological transformation in Shizuishan City. Among them, the Low-Carbon Economic Development Scenario exhibited the largest improvement area, reaching 75.81 %. (3) Ecological system vitality was identified as the dominant dimension influencing the ecological health in this region. This study emphasized multi-objective development needs and provided an integrated ecosystem health assessment method for assessing the comprehensive ecological effects of future ecological transformation modes in resource-exhausted cities.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Cidades , China , Carbono
12.
Mar Pollut Bull ; 200: 116126, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38330813

RESUMO

The present study assessed the trophic status of a medium-sized microtidal estuary, Rushikulya, India using a combination of mutimetric trophic indices (TRIX, TRBIX) and a machine learning approach (Random Forest). A total of 108 samples were considered to build a predictive model for chlorophyll a (Chl a) and 17 response water variables by observing two annual periods (2021-2023) at six sampling sites. Mean values of TRIX (5.04 ± 0.72) and TRBIX (0.17 ± 0.08) reflected that the estuary has a moderate degree of eutrophication with 'good' water quality and 'biomass saturated'. However, the threshold of TRIX represents a transition state from 'moderate' to 'high' eutrophic. Random Forest model reflected that no apparent association between Chl a and water turbidity above 30 NTU and eutrophication in the estuary fluctuated mainly due to PO43--P along with electrical conductivity. Linear statistical correlations showed high correlation between Chl a and conductivity and a negative correlation between Chl a and dissolved oxygen, unlike PO43--P.


Assuntos
Monitoramento Ambiental , Estuários , Clorofila A , Algoritmo Florestas Aleatórias , Qualidade da Água , Eutrofização , Clorofila/análise
13.
Environ Monit Assess ; 196(2): 206, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38279061

RESUMO

Evaluating the ecosystem health of riparian zones is helpful for decision-makers to formulate appropriate management measures. However, there are few methods for such evaluation which account for both the human requirements and ecological aspects of riparian zones. To address this, we created a Pressure-State(Vigor-Organization-Resilience)-Response framework for evaluating the ecosystem health of the riparian zone of the Yangtze River in Jiangsu Province, a region experiencing intense land use changes. Evaluation indicators, including land use change and ecosystem services, were selected. The comprehensive index method was used to calculate the evaluation indicators of ecosystem health, namely pressure, state, and response, and the comprehensive evaluation indicator itself. Using the cold and hot spot analysis, we also analyzed the spatial heterogeneity of ecosystem health in the riparian zone, constructed an ecological management pattern, and proposed corresponding management and protection measures. The results show that (1) from 2010 to 2020, construction land in the study area increased by more than 20%, and all studied land types underwent some degree of conversion to construction land, with cultivated land and water bodies being the main focus of conversion. (2) In 2020, the average ecosystem health in the riparian zone was normal, with a spatial distribution characterized by "high dispersion and low clustering"; and (3) according to the results of the ecosystem health evaluation and cold and hot spot analysis, key areas for stronger ecological protection were identified and, based on this, a number of management recommendations were proposed.


Assuntos
Ecossistema , Rios , Humanos , Monitoramento Ambiental , China , Conservação dos Recursos Naturais/métodos
14.
Mar Pollut Bull ; 199: 115950, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38183833

RESUMO

Various environmental indicators were used to evaluate the water and sediment quality of the Netravathi-Gurupur estuary, India, for trace metals and pesticide pollution. The descended order of studied metal concentrations (µg/L) in the water was Fe (592.71) > Mn (98.35) > Zn (54.69) > Cu (6.64) > Cd (3.24) > Pb (2.38) > Cr (0.82) and in sediment (mg/kg) was Fe (11,396.53) > Mn (100.61) > Cr (75.41) > Zn (20.04) > Cu (12.77) > Pb (3.46) > Cd (0.02). However, pesticide residues were not detected in this estuarine environment. The various metal indexes categorised the water as uncontaminated, whereas contamination factor, enrichment factor, geo-accumulation index, degree of contamination and pollution load index indicated low to moderate sediment contamination. Multivariate statistics showed that the dominance of natural sources of trace metals with little anthropogenic impact. Improvement in water/sediment quality during the study period might be due to COVID-19 imposed lockdown.


Assuntos
Metais Pesados , Praguicidas , Poluentes Químicos da Água , Metais Pesados/análise , Estuários , Sedimentos Geológicos/química , Água , Poluentes Químicos da Água/análise , Cádmio , Chumbo , Monitoramento Ambiental , Índia , Medição de Risco
15.
Huan Jing Ke Xue ; 45(1): 218-227, 2024 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-38216473

RESUMO

Exploring ecosystem health and its influencing factors is of great significance for promoting regional sustainable development. An ecosystem health assessment model was constructed, and the spatial-temporal evolution characteristics of ecosystem health in the Beijing-Tianjin-Hebei Region in 2000, 2010, and 2020 were analyzed. The geographical detector and GWR were used to identify the dominant factors affecting ecosystem health. The main conclusions were as follows:during the study period, the index of ecosystem natural health in the Beijing-Tianjin-Hebei Region was generally better in the north and west than that in the southeast, and it showed an overall upward trend. The index of ecosystem services in the Beijing-Tianjin-Hebei Region presented as a spatial differentiation pattern of high in the north and low in the south, and it showed a downward trend. The ecosystem health level in the Beijing-Tianjin-Hebei Region showed a trend of rising first and then declining, showing significant heterogeneity in spatial distribution. The ecological health level in the central urban area of large cities was mostly poor, and the ecosystem health level in the Yanshan and Taihang Mountains and Bohai Rim was better. During the study period, the spatial pattern of ecosystem health in the Beijing-Tianjin-Hebei Region remained relatively stable. The hot spots and sub-hot spots were mainly distributed in the northern mountainous areas of Hebei Province and the Taihang Mountains, and the cold spots and sub-cold spots were mainly distributed in the southeast plain and the surrounding areas of some big cities. Population density, annual average temperature, per capita cultivated land area, and urbanization level were the dominant factors of ecosystem health in the Beijing-Tianjin-Hebei Region, and they were all negatively correlated with ecosystem health.


Assuntos
Ecossistema , Urbanização , Pequim , Cidades , Temperatura , China
16.
Sci Total Environ ; 913: 169667, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38163603

RESUMO

Invasive alien species are considered one of the greatest threats to global biodiversity, and are particularly problematic in aquatic systems. Given the foundational role of macrophytes in most freshwaters, alien aquatic plant invasions may drive strong bottom-up impacts on recipient biota. Crassula helmsii (New Zealand pygmyweed) is an Australasian macrophyte, now widespread in northwest Europe. Crassula helmsii rapidly invades small lentic waterbodies, where it is generally considered a serious threat to native biodiversity. The precise ecological impacts of this invasion remain poorly understood, however, particularly with respect to macroinvertebrates, which comprise the bulk of freshwater faunal biodiversity. We conducted a field study of ponds, ditches and small lakes across the core of C. helmsii's invasive range (United Kingdom, Belgium and the Netherlands), finding that invaded sites had higher macroinvertebrate taxon richness than uninvaded sites, and that many infrequent and rare macroinvertebrates co-occurred with C. helmsii. Alien macroinvertebrates were more abundant in C. helmsii sites, however, particularly the North American amphipod Crangonyx pseudogracilis. At the order level, water beetle (Coleoptera) richness and abundance were higher in C. helmsii sites, whereas true fly (Diptera) abundance was higher in uninvaded sites. Taxonomic and functional assemblage composition were both impacted by invasion, largely in relation to taxa and traits associated with detritivory, suggesting that the impacts of C. helmsii on macroinvertebrates are partly mediated by the availability and palatability of its detritus. The nuanced effects of C. helmsii on macroinvertebrates found here should encourage further quantitative research on the impacts of this invasive plant, and perhaps prompt a more balanced re-evaluation of its effects on native aquatic macrofauna.


Assuntos
Besouros , Dípteros , Animais , Invertebrados , Ecossistema , Biodiversidade , Espécies Introduzidas , Plantas , Lagos
17.
Sci Total Environ ; 914: 169812, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38181942

RESUMO

The present study examined the defense responses of toxigenic Pseudo-nitzschia species (P. multiseries) to a mixotrophic dinoflagellate, Lepidodinium sp., and its associated cues. We evaluated their responses to different predation risks, including direct physical contact and indirect interactions facilitated by cues from Lepidodinium sp. during active feeding on heterospecific prey (Rhodonomas salina), limited feeding on conspecific prey (P. multiseries) and non-feeding (autotrophic growth in f/2 medium) states. This study is the first investigation of these trophic interactions. Our results demonstrated a significant increase in cellular domoic acid (cDA) in P. multiseries when exposed to Lepidodinium sp. and its associated cues, which was 1.38 to 2.42 times higher than the non-induced group. Notably, this increase was observed regardless of Lepidodinium sp. feeding on this toxic diatom and nutritional modes. However, the most significant increase occurred when they directly interacted. These findings suggest that P. multiseries evaluates predation risk and increases cDA production as a defensive strategy against potential grazing threats. No morphological changes were observed in P. multiseries in response to Lepidodinium sp. or its cues. P. multiseries cultured in flasks of Group L+P-P showed a decrease in growth, but Group L-P and Group L+R-P did not exhibit any decrease. These results suggest a lack of consistent trade-offs between the defense response and growth, thus an increase in cDA production may be a sustainable and efficient defense strategy for P. multiseries. Furthermore, our findings indicate that P. multiseries had no significant impact on the fitness (cell size, growth and/or grazing) of Lepidodinium sp. and R. salina, which suggests no evident toxic or allelopathic impacts on these two phytoplankton species. This study enhances our understanding of the trophic interactions between toxic diatoms and mixotrophic dinoflagellates and helps elucidate the dynamics of Harmful Algal Blooms, toxin transmission, and their impact on ecosystem health.


Assuntos
Artrópodes , Diatomáceas , Dinoflagellida , Animais , Diatomáceas/fisiologia , Ecossistema , Sinais (Psicologia) , Toxinas Marinhas
18.
Sci Total Environ ; 914: 169981, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38215845

RESUMO

The coastal zone is typically highly developed and its ocean environment is vastly exposed to the onshore activities. Land-based pollution, as the "metabolite" of terrestrial human activities, significantly impacts the ocean environment. Although numerous studies have investigated these effects, few have quantified the interactions among land-human activity-ocean across both spatial and temporal scales. In this study, we have developed a land-human activity-ocean systemic framework integrating the coupling coordination degree model and tipping point to quantify the spatiotemporal dynamic interaction mechanism among the land-based pollution, human activities, and ocean environment in China from 2001 to 2020. Our findings revealed that the overall coupling coordination degree of the China's coastal zone increased by 36.9 % over last two decades. Furthermore, the effect of human activities on China's coastal environment remained within acceptable thresholds, as no universal tipping points for coastal pollution or ocean environment has been found over the 20-year period. Notably, the lag time for algal blooms, the key indicator of ocean environment health, was found to be 0-3 years in response to the land economic development and 0-4 years in response to land-based pollution. Based on the differences in spatiotemporal interactions among land-human activity-ocean system, we employed cluster analysis to categorize China's coastal provinces into four types and to develop appropriate management measures. Quantifying the interaction mechanism within the land-human activity-ocean system could aid decision-makers in creating sustainable coastal development strategies. This enables efficient use of land and ocean resources, supports coastal conservation and restoration efforts, and fosters effective management recommendations to enhance coastal sustainability and resilience.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Humanos , Poluição Ambiental , China , Oceanos e Mares
19.
Environ Res ; 242: 117665, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37993051

RESUMO

In this investigation, the presence of antibiotics and pharmaceuticals in Costa Rican surface waters, specifically in regions near feline habitats, was examined. The study revealed that 47% of the water samples contained detectable traces of at least one antibiotic. Ciprofloxacin and norfloxacin were the most frequently detected compounds, each with a detection rate of 27%. Other antibiotics, such as erythromycin, roxithromycin, and trimethoprim, were also found but at lower frequencies, around 14%. Notably, all antibiotic concentrations remained below 10 ng/L, with ciprofloxacin, norfloxacin, and erythromycin showing the highest concentrations. Furthermore, the investigation revealed the presence of non-antibiotic pharmaceutical residues in the water samples, typically at concentrations below 64 ng/L. Tramadol was the most frequently detected compound, present in 18% of the samples. The highest concentrations were observed for acetaminophen and tramadol, measuring 64 and 10 ng/L, respectively. Comparing these findings with studies conducted in treated wastewater and urban rivers, it became evident that the concentrations of antibiotics and pharmaceuticals were notably lower in this study. While previous research reported higher values, the limited number of studies conducted in protected areas raises concerns about the potential environmental impact on biodiversity. In summary, these results emphasize the importance of monitoring pharmaceutical residues and antimicrobial resistance genes ARGs in vulnerable ecosystems, especially those in close proximity to feline habitats in Costa Rica. Additionally, the study delved into the detection of (ARGs). All tested water samples were positive for at least one ARG, with the blaTEM gene being the most prevalent at 82%, followed by tetS at 64% and qnrB at 23%. Moreover, this research shed light on the complexity of evaluating ARGs in environmental samples, as their presence does not necessarily indicate their expression. It also highlighted the potential for co-selection and co-regulation of ARGs, showcasing the intricate behaviors of these genes in aquatic environments.


Assuntos
Roxitromicina , Tramadol , Poluentes Químicos da Água , Gatos , Animais , Antibacterianos/farmacologia , Antibacterianos/análise , Costa Rica , Farmacorresistência Bacteriana , Norfloxacino , Ecossistema , Ciprofloxacina , Preparações Farmacêuticas , Água , Rios/química , Monitoramento Ambiental , Poluentes Químicos da Água/análise
20.
Sci Total Environ ; 912: 168891, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38042183

RESUMO

Urban expansion is a global phenomenon that impacts biodiversity loss and climate change. Soil sealing increases land degradation and the ecosystem services supply. This degradation also negatively affects ecosystem health, essential to make cities more sustainable and liveable. This work aims to study the ecosystem health spatiotemporal evolution (1990, 2000, 2006, 2012 and 2018) in the Vilnius (Lithuania) functional zone, using the vigour, organisation and resilience (VOR) method. The results showed that ecosystem health model validation was acceptable (r = -0.761; p < 0.01). Between 1990 and 2018, an increase (18.37 %) in ecosystem vigour was observed. The values were significantly higher in 2006, 2012 and 2018 than in 1990 and 2000. We identified a decrease between 1990 and 2018 regarding ecosystem organisation (7.15 %) and resilience (9.92 %). However, no significant differences between the years were identified. Ecosystem health decreased (11.49 %) between 1990 and 2018, mainly between 2012 and 2018. Ecosystem health values in 2018 were significantly lower than those identified in the previous years. The lowest values of ecosystem vigour, organisation and resilience were identified in the Vilnius city centre, while the highest was observed in the Vilnius functional zone. From 1990 to 2018, ecosystem vigour increased in some elderships located on the fringe of the studied area due to land abandonment and forest plantations. Simultaneously, a decrease in ecosystem organisation and resilience in the elderships located in Vilnius city centre was observed due to urban sprawl and the consequent landscape fragmentation. This negatively impacted ecosystem health, overshadowing the positive trend observed in ecosystem vigour. Different processes (e.g., urban sprawl, land abandonment, forest plantations) occurred in the Vilnius functional zone. It is essential to halt urban expansion and its adverse impacts on ecosystem health, city sustainability and liveability.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Lituânia , Florestas , Cidades , China
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