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1.
Nature ; 620(7974): 582-588, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37558875

RESUMO

Owing to a long history of anthropogenic pressures, freshwater ecosystems are among the most vulnerable to biodiversity loss1. Mitigation measures, including wastewater treatment and hydromorphological restoration, have aimed to improve environmental quality and foster the recovery of freshwater biodiversity2. Here, using 1,816 time series of freshwater invertebrate communities collected across 22 European countries between 1968 and 2020, we quantified temporal trends in taxonomic and functional diversity and their responses to environmental pressures and gradients. We observed overall increases in taxon richness (0.73% per year), functional richness (2.4% per year) and abundance (1.17% per year). However, these increases primarily occurred before the 2010s, and have since plateaued. Freshwater communities downstream of dams, urban areas and cropland were less likely to experience recovery. Communities at sites with faster rates of warming had fewer gains in taxon richness, functional richness and abundance. Although biodiversity gains in the 1990s and 2000s probably reflect the effectiveness of water-quality improvements and restoration projects, the decelerating trajectory in the 2010s suggests that the current measures offer diminishing returns. Given new and persistent pressures on freshwater ecosystems, including emerging pollutants, climate change and the spread of invasive species, we call for additional mitigation to revive the recovery of freshwater biodiversity.


Assuntos
Biodiversidade , Conservação dos Recursos Hídricos , Monitoramento Ambiental , Água Doce , Invertebrados , Animais , Espécies Introduzidas/tendências , Invertebrados/classificação , Invertebrados/fisiologia , Europa (Continente) , Atividades Humanas , Conservação dos Recursos Hídricos/estatística & dados numéricos , Conservação dos Recursos Hídricos/tendências , Hidrobiologia , Fatores de Tempo , Produção Agrícola , Urbanização , Aquecimento Global , Poluentes da Água/análise
2.
J Environ Manage ; 364: 121427, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38870790

RESUMO

Tidal wetlands play a critical role in emitting greenhouse gases (GHGs) into the atmosphere; our understanding of the intricate interplay between natural processes and human activities shaping their biogeochemistry and GHG emissions remains lacking. In this study, we delve into the spatiotemporal dynamics and key drivers of the GHG emissions from five tidal wetlands in the Scheldt Estuary by focusing on the interactive impacts of salinity and water pollution, two factors exhibiting contrasting gradients in this estuarine system: pollution escalates as salinity declines. Our findings reveal a marked escalation in GHG emissions when moving upstream, primarily attributed to increased concentrations of organic matter and nutrients, coupled with reduced levels of dissolved oxygen and pH. These low water quality conditions not only promote methanogenesis and denitrification to produce CH4 and N2O, respectively, but also shift the carbonate equilibria towards releasing more CO2. As a result, the most upstream freshwater wetland was the largest GHG emitter with a global warming potential around 35 to 70 times higher than the other wetlands. When moving seaward along a gradient of decreasing urbanization and increasing salinity, wetlands become less polluted and are characterized by lower concentrations of NO3-, TN and TOC, which induces stronger negative impact of elevated salinity on the GHG emissions from the saline wetlands. Consequently, these meso-to polyhaline wetlands released considerably smaller amounts of GHGs. These findings emphasize the importance of integrating management strategies, such as wetland restoration and pollution prevention, that address both natural salinity gradients and human-induced water pollution to effectively mitigate GHG emissions from tidal wetlands.


Assuntos
Gases de Efeito Estufa , Salinidade , Poluição da Água , Áreas Alagadas , Gases de Efeito Estufa/análise , Estuários , Monitoramento Ambiental
3.
Environ Monit Assess ; 196(6): 578, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38795160

RESUMO

Monitoring water quality and quantity is crucial to be sure that water resources are sustainably used. However, there is no monitoring system of water quantity and quality in southwestern Ethiopia, despite expansion of agricultural activities demanding water resources. The objective of this study was to investigate the effect of agriculture on water quantity and quality with special emphasis on irrigation in southwestern Ethiopia. Data of water quantity was collected from four rivers and four irrigation canals during dry season of 2023. Physico-chemical water quality data was collected from 35 sites. Water quantity was calculated by estimating the water discharge of the rivers and irrigation canals. Weighted arithmetic water quality index was calculated to assess the status of the studied rivers. Principal component analysis was used to identify the relation of the sites with water quality parameters. This study revealed that the average amount of abstracted water for irrigation from the four studied rivers was 22,399 m3/day during the studied period, and the average percentage of abstracted water was 17%. Sites downstream of the irrigation site were characterized by poor water quality compared with the upstream sites. Sites surrounded by agricultural land use were correlated with chemical oxygen demand, electric conductivity, nitrate, orthophosphate, water temperature, and pH, whereas all sites surrounded by forest were positively correlated with dissolved oxygen. This study indicates that agricultural activities have a negative impact on surface water quality and quantity if not managed properly. Hence, we recommend sustainable use of water resources for the planned irrigation expansion.


Assuntos
Agricultura , Monitoramento Ambiental , Rios , Qualidade da Água , Etiópia , Rios/química , Irrigação Agrícola , Poluentes Químicos da Água/análise , Abastecimento de Água/estatística & dados numéricos , Nitratos/análise
4.
Ecol Lett ; 26(2): 313-322, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36592335

RESUMO

The sixth mass extinction is a consequence of complex interplay between multiple stressors with negative impact on biodiversity. We here examine the interaction between two globally widespread anthropogenic drivers of amphibian declines: the fungal disease chytridiomycosis and antifungal use in agriculture. Field monitoring of 26 amphibian ponds in an agricultural landscape shows widespread occurrence of triazole fungicides in the water column throughout the amphibian breeding season, together with a negative correlation between early season application of epoxiconazole and the prevalence of chytrid infections in aquatic newts. While triazole concentrations in the ponds remained below those that inhibit growth of Batrachochytrium dendrobatidis, they bioaccumulated in the newts' skin up to tenfold, resulting in cutaneous growth-suppressing concentrations. As such, a concentration of epoxiconazole, 10 times below that needed to inhibit fungal growth, prevented chytrid infection in anuran tadpoles. The widespread presence of triazoles may thus alter chytrid dynamics in agricultural landscapes.


Assuntos
Quitridiomicetos , Micoses , Praguicidas , Animais , Melhoramento Vegetal , Micoses/epidemiologia , Micoses/veterinária , Anfíbios/microbiologia , Triazóis/farmacologia
5.
J Environ Manage ; 335: 117538, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36848809

RESUMO

River fragmentation is an increasing issue for water managers and conservationists. Barriers such as dams interfere with freshwater fish migration, leading to drastic population declines. While there are a range of widely implemented mitigation approaches, e.g. fish passes, such measures are often inefficient due to suboptimal operation and design. There is increasing need to be able to assess mitigation options prior to implementation. Individual based models (IBMs) are a promising option. IBMs can simulate the fine-scale movement of individual fish within a population as they attempt to find a fish pass, incorporating movement processes themselves. Moreover, IBMs have high transferability to other sites or conditions (e.g. changing mitigation, change in flow conditions), making them potentially valuable for freshwater fish conservation yet their application to the fine-scale movement of fish past barriers is still novel. Here, we present an overview of existing IBMs for fine-scale freshwater fish movement, with emphasis on study species and the parameters driving movement in the models. In this review, we focus on IBMs suitable for the simulation of fish tracks as they approach or pass a single barrier. The selected IBMs for modelling fine-scale freshwater fish movement largely focus on salmonids and cyprinid species. IBMs have many applications in the context of fish passage, such as testing different mitigation options or understanding processes behind movement. Existing IBMs include movement processes such as attraction and rejection behaviours, as reported in literature. Yet some factors affecting fish movement e.g. biotic interactions are not covered by existing IBMs. As the technology available for fine scale data collection continues to advance, such as increasing data linking fish behaviour to hydraulics, IBMs could become a more common tool in the design and implementation of fish bypass structures.


Assuntos
Condução de Veículo , Peixes , Animais , Simulação por Computador , Rios , Migração Animal
6.
Environ Monit Assess ; 195(8): 988, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37490187

RESUMO

Pesticide use has increased in the Lake Tana sub-basin due to increased agricultural activity, potentially endangering nontargeted organisms. To assess its potential impact on fish health and fish-consuming human populations, pesticide concentrations in the fillet and liver tissue of three fish species, namely Labeobarbus megastoma, Labeobarbus tsanensis, and Oreochromis niloticus, were investigated in Lake Tana. Fish samples were taken from the lake near the rivers of Ribb and Gumara, which flow through agricultural areas where considerable amounts of pesticides have been applied. A total of 96 fish samples were collected. Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) revealed the presence of ten pesticides. Pyrimethanil was frequently detected in 96% of liver and 65% of fillet samples at a median concentration of 33.9 µg kg-1 and 19.7 µg kg-1, respectively. The highest concentration of pyrimethanil was found in L. megastoma (1850.0 µg kg-1). Labeobarbus megastoma also had the highest concentration of oxamyl (507.0 µg kg-1) and flazasulfuron (60.1 µg kg-1) detected in the liver tissue. The highest concentration of carbaryl (56.5 µg kg-1) was found in the liver tissue of O. niloticus. Fish tissue samples from the two study sites contained pyrimethanil, oxamyl, carbaryl, and flazasulfuron. Only pyrimethanil showed a statistically significant difference between the two sites and the species L. megastoma and L. tsanensis. The amounts of pesticides found in the fish species pose no direct risk to the health of fish consumer human population. However, the results show that the lake ecosystem needs immediate attention and regular monitoring of the rising pesticide usage in the lake watershed.


Assuntos
Ciclídeos , Praguicidas , Animais , Humanos , Etiópia , Carbaril , Cromatografia Líquida , Ecossistema , Lagos , Espectrometria de Massas em Tandem , Monitoramento Ambiental
7.
Ecol Lett ; 25(2): 255-263, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34854211

RESUMO

Global freshwater biodiversity is declining dramatically, and meeting the challenges of this crisis requires bold goals and the mobilisation of substantial resources. While the reasons are varied, investments in both research and conservation of freshwater biodiversity lag far behind those in the terrestrial and marine realms. Inspired by a global consultation, we identify 15 pressing priority needs, grouped into five research areas, in an effort to support informed stewardship of freshwater biodiversity. The proposed agenda aims to advance freshwater biodiversity research globally as a critical step in improving coordinated actions towards its sustainable management and conservation.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , Água Doce
8.
Glob Chang Biol ; 28(15): 4620-4632, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35570183

RESUMO

Globalization has led to the introduction of thousands of alien species worldwide. With growing impacts by invasive species, understanding the invasion process remains critical for predicting adverse effects and informing efficient management. Theoretically, invasion dynamics have been assumed to follow an "invasion curve" (S-shaped curve of available area invaded over time), but this dynamic has lacked empirical testing using large-scale data and neglects to consider invader abundances. We propose an "impact curve" describing the impacts generated by invasive species over time based on cumulative abundances. To test this curve's large-scale applicability, we used the data-rich New Zealand mud snail Potamopyrgus antipodarum, one of the most damaging freshwater invaders that has invaded almost all of Europe. Using long-term (1979-2020) abundance and environmental data collected across 306 European sites, we observed that P. antipodarum abundance generally increased through time, with slower population growth at higher latitudes and with lower runoff depth. Fifty-nine percent of these populations followed the impact curve, characterized by first occurrence, exponential growth, then long-term saturation. This behaviour is consistent with boom-bust dynamics, as saturation occurs due to a rapid decline in abundance over time. Across sites, we estimated that impact peaked approximately two decades after first detection, but the rate of progression along the invasion process was influenced by local abiotic conditions. The S-shaped impact curve may be common among many invasive species that undergo complex invasion dynamics. This provides a potentially unifying approach to advance understanding of large-scale invasion dynamics and could inform timely management actions to mitigate impacts on ecosystems and economies.


Assuntos
Ecossistema , Espécies Introduzidas , Animais , Europa (Continente) , Nova Zelândia , Caramujos
9.
J Environ Manage ; 294: 112999, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34118519

RESUMO

Surrounded by intense anthropogenic activities, urban polluted rivers have increasingly been reported as a significant source of greenhouse gases (GHGs). However, unlike pollution and climate change, no integrated urban water models have investigated the GHG production in urban rivers due to system complexity. In this study, we proposed a novel integrated framework of mechanistic and data-driven models to qualitatively assess the risks of GHG accumulation in an urban river system in different water management interventions. Particularly, the mechanistic model delivered elaborated insights into river states in four intervention scenarios in which the installation of a new wastewater treatment plant using two different technologies, together with new sewage systems and additional retention tanks, were assessed during dry and rainy seasons. From the insights, we applied fuzzy rule-based models as a decision support tool to predict the GHG accumulation risks and identify their driving factors in the scenarios. The obtained results indicated the important role of new discharge connection and additional storage capacity in decreasing pollutant concentrations, consequently, reducing the risks. Moreover, among the major variables explaining the GHG accumulation in the rivers, DO level was considerably affected by the reaeration capacity of the rivers that was strongly dependent on river slope and flow. Furthermore, river water quality emerged as the most critical variable explaining the pCO2 and N2O accumulation that implied that the more polluted and anaerobic the sites were, the higher were their GHG accumulation. Given its simplicity and transparency, the proposed modeling framework can be applied to other river basins as a decision support tool in setting up integrated urban water management plans.


Assuntos
Gases de Efeito Estufa , Monitoramento Ambiental , Gases de Efeito Estufa/análise , Medição de Risco , Rios , Poluição da Água/análise , Qualidade da Água
10.
Water Sci Technol ; 78(1-2): 37-48, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30101787

RESUMO

Algal photosynthesis plays a key role in the removal mechanisms of waste stabilization ponds (WSPs), which is indicated in the variations of three parameters, dissolved oxygen, pH, and chlorophyll a. These variations can be considerably affected by extreme climatic conditions at high altitude. To investigate these effects, three sampling campaigns were conducted in a high-altitude WSP in Cuenca (Ecuador). From the collected data, the first application of structure equation modeling (SEM) on a pond system was fitted to analyze the influence of high-altitude characteristics on pond performance, especially on the three indicators. Noticeably, air temperature appeared as the highest influencing factors as low temperature at high altitude can greatly decrease the growth rate of microorganisms. Strong wind and large diurnal variations of temperature, 7-20 °C, enhanced flow efficiency by improving mixing inside the ponds. Intense solar radiation brought both advantages and disadvantages as it boosted oxygen level during the day but promoted algal overgrowth causing oxygen depletion during the night. From these findings, the authors proposed insightful recommendations for future design, monitoring, and operation of high-altitude WSPs. Moreover, we also recommended SEM to pond engineers as an effective tool for better simulation of such complex systems like WSPs.


Assuntos
Lagoas , Eliminação de Resíduos Líquidos/estatística & dados numéricos , Purificação da Água/estatística & dados numéricos , Tempo (Meteorologia) , Altitude , Equador , Modelos Biológicos , Oxigênio/metabolismo , Energia Solar , Temperatura
11.
Europace ; 18(12): 1779-1786, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27170000

RESUMO

AIMS: Despite the increased prevalence of atrial fibrillation (AF), data for the implementation of nationwide screening programmes are limited. The aim of this national screening study was to increase nationwide awareness about AF and stroke risk, to determine the prevalence of AF in Belgian general population using an ECG handheld machine and its feasibility to identify new AF cases. METHODS AND RESULTS: We analysed data obtained from 5 years of the 'Belgian Heart Rhythm Week' screening programme. All subjects were screened using a one-lead ECG handheld machine. Among 65 747 subjects screened, AF was recorded in 911, with an overall prevalence of 1.4% [95% confidence interval (CI) 1.2-1.6%]. High thrombo-embolic risk, as assessed by CHA2DS2-VASc score ≥2, was recorded in 69% of AF subjects. In subjects with high thrombo-embolic risk, only 5.4% were treated with oral anticoagulant (OAC) and 5.8% were treated with OAC and antiplatelet drugs. Among recorded AF cases, the use of the ECG handheld machine allowed identification of 603 new AF patients (1.1%, 95% CI 0.9-1.3%). Factors associated with incident AF were chronic heart failure (P < 0.001), age (P < 0.001), diabetes mellitus (P < 0.001), previous stroke (P < 0.001), vascular disease (P < 0.001), and male sex (P < 0.001). CONCLUSION: In this Belgian national screening programme, prevalence of AF was 1.4%. The use of an ECG handheld machine is feasible to identify a significant number of new AF cases, most with a high thrombo-embolic risk. Given the low OAC use recorded, greater efforts in AF detection and treatment are urgently needed to reduce the burden of stroke associated with this common arrhythmia.


Assuntos
Fibrilação Atrial/epidemiologia , Eletrocardiografia/instrumentação , Programas de Rastreamento/métodos , Acidente Vascular Cerebral/prevenção & controle , Administração Oral , Idoso , Anticoagulantes/administração & dosagem , Fibrilação Atrial/tratamento farmacológico , Bélgica/epidemiologia , Complicações do Diabetes , Feminino , Insuficiência Cardíaca/complicações , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Medição de Risco , Fatores de Risco
12.
Environ Manage ; 58(4): 694-706, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27357809

RESUMO

Despite the increasing levels of pollution in many tropical African countries, not much is known about the strength and weaknesses of policy and institutional frameworks to tackle pollution and ecological status of rivers and their impacts on the biota. We investigated the ecological status of four large river basins using physicochemical water quality parameters and bioindicators by collecting samples from forest, agriculture, and urban landscapes of the Nile, Omo-Gibe, Tekeze, and Awash River basins in Ethiopia. We also assessed the water policy scenario to evaluate its appropriateness to prevent and control pollution. To investigate the level of understanding and implementation of regulatory frameworks and policies related to water resources, we reviewed the policy documents and conducted in-depth interviews of the stakeholders. Physicochemical and biological data revealed that there is significant water quality deterioration at the impacted sites (agriculture, coffee processing, and urban landscapes) compared to reference sites (forested landscapes) in all four basins. The analysis of legal, policy, and institutional framework showed a lack of cooperation between stakeholders, lack of knowledge of the policy documents, absence of enforcement strategies, unavailability of appropriate working guidelines, and disconnected institutional setup at the grass root level to implement the set strategies as the major problems. In conclusion, river water pollution is a growing challenge and needs urgent action to implement intersectoral collaboration for water resource management that will eventually lead toward integrated watershed management. Revision of policy and increasing the awareness and participation of implementers are vital to improve ecological quality of rivers.


Assuntos
Conservação dos Recursos Naturais/métodos , Países em Desenvolvimento , Monitoramento Ambiental/métodos , Rios/química , Poluição da Água/prevenção & controle , Qualidade da Água/normas , Agricultura , Etiópia
13.
Environ Sci Technol ; 49(14): 8704-11, 2015 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-26079074

RESUMO

We analyzed three decades of field observations in the North Sea with additive models to infer spatiotemporal trends of chlorophyll a concentration, sediment organic carbon content, and polychlorinated biphenyls (PCBs) concentrations in mussels and sediments. By doing so, we separated long-term changes in PCB concentrations from seasonal variability. Using the inferred seasonal variability, we demonstrated that phytoplankton blooms in spring and autumn correspond to the annual maxima of the organic carbon content (r = 0.56; p = 0.004) and the PCB concentrations in sediments (r = 0.57; p = 0.004). Furthermore, we found a negative correlation between the PCB concentrations in sediments and in blue mussels (Mytilus edulis; r = -0.33, p = 0.012), which is probably related to the cleansing of the dissolved PCB phase driven by sinking organic matter during phytoplankton blooms and the filter-feeding behavior of the blue mussel. The present research demonstrates the role of seasonal phytoplankton dynamics in the environmental fate of PCBs at large spatiotemporal scales.


Assuntos
Biota , Monitoramento Ambiental , Sedimentos Geológicos/química , Fitoplâncton/crescimento & desenvolvimento , Bifenilos Policlorados/análise , Animais , Clorofila/análise , Clorofila A , Modelos Biológicos , Mytilus edulis/química , Estações do Ano , Fatores de Tempo , Poluentes Químicos da Água/análise
14.
J Environ Manage ; 145: 79-87, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25005053

RESUMO

Freshwater ponds deliver a broad range of ecosystem services (ESS). Taking into account this broad range of services to attain cost-effective ESS delivery is an important challenge facing integrated pond management. To assess the strengths and weaknesses of an ESS approach to support decisions in integrated pond management, we applied it on a small case study in Flanders, Belgium. A Bayesian belief network model was developed to assess ESS delivery under three alternative pond management scenarios: intensive fish farming (IFF), extensive fish farming (EFF) and nature conservation management (NCM). A probabilistic cost-benefit analysis was performed that includes both costs associated with pond management practices and benefits associated with ESS delivery. Whether or not a particular ESS is included in the analysis affects the identification of the most preferable management scenario by the model. Assessing the delivery of a more complete set of ecosystem services tends to shift the results away from intensive management to more biodiversity-oriented management scenarios. The proposed methodology illustrates the potential of Bayesian belief networks. BBNs facilitate knowledge integration and their modular nature encourages future model expansion to more encompassing sets of services. Yet, we also illustrate the key weaknesses of such exercises, being that the choice whether or not to include a particular ecosystem service may determine the suggested optimal management practice.


Assuntos
Conservação dos Recursos Naturais/economia , Ecologia/métodos , Ecossistema , Disseminação de Informação , Lagoas , Teorema de Bayes , Bélgica , Análise Custo-Benefício , Ecologia/economia , Modelos Estatísticos , Risco
15.
Water Sci Technol ; 70(11): 1798-807, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25500469

RESUMO

Worldwide, large investments in wastewater treatment are made to improve water quality. However, the impacts of these investments on river water quality are often not quantified. To assess water quality, the European Water Framework Directive (WFD) requires an integrated approach. The aim of this study was to develop an integrated ecological modelling framework for the River Drava (Croatia) that includes physical-chemical and hydromorphological characteristics as well as the ecological river water quality status. The developed submodels and the integrated model showed accurate predictions when comparing the modelled results to the observations. Dissolved oxygen and nitrogen concentrations (ammonium and organic nitrogen) were the most important variables in determining the ecological water quality (EWQ). The result of three potential investment scenarios of the wastewater treatment infrastructure in the city of Varazdin on the EWQ of the River Drava was assessed. From this scenario-based analysis, it was concluded that upgrading the existing wastewater treatment plant with nitrogen and phosphorus removal will be insufficient to reach a good EWQ. Therefore, other point and diffuse pollution sources in the area should also be monitored and remediated to meet the European WFD standards.


Assuntos
Investimentos em Saúde , Modelos Teóricos , Águas Residuárias , Purificação da Água/economia , Qualidade da Água/normas , Cidades , Ecossistema , Água Doce/química , Poluentes Químicos da Água/química
16.
Water Res ; 250: 121012, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38128303

RESUMO

Despite the recognized importance of flowing waters in global greenhouse gas (GHG) budgets, riverine GHG models remain oversimplified, consequently restraining the development of effective prediction for riverine GHG emissions feedbacks. Here we elucidate the state of the art of riverine GHG models by investigating 148 models from 122 papers published from 2010 to 2021. Our findings indicate that riverine GHG models have been mostly data-driven models (83%), while mechanistic and hybrid models were uncommonly applied (12% and 5%, respectively). Overall, riverine GHG models were mainly used to explain relationships between GHG emissions and biochemical factors, while the role of hydrological, geomorphic, land use and cover factors remains missing. The development of complex and advanced models has been limited by data scarcity issues; hence, efforts should focus on developing affordable automatic monitoring methods to improve data quality and quantity. For future research, we request for basin-scale studies explaining river and land-surface interactions for which hybrid models are recommended given their flexibility. Such a holistic understanding of GHG dynamics would facilitate scaling-up efforts, thereby reducing uncertainties in global GHG estimates. Lastly, we propose an application framework for model selection based on three main criteria, including model purpose, model scale and the spatiotemporal characteristics of GHG data, by which optimal models can be applied in various study conditions.


Assuntos
Gases de Efeito Estufa , Gases de Efeito Estufa/análise , Rios , Efeito Estufa , Dióxido de Carbono
17.
Plants (Basel) ; 13(7)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38611543

RESUMO

Streams are biodiversity hotspots that provide numerous ecosystem services. Safeguarding this biodiversity is crucial to uphold sustainable ecosystem functioning and to ensure the continuation of these ecosystem services in the future. However, in recent decades, streams have witnessed a disproportionate decline in biodiversity compared to other ecosystems, and are currently considered among the most threatened ecosystems worldwide. This is the result of the combined effect of a multitude of stressors. For freshwater systems in general, these have been classified into five main pressures: water pollution, overexploitation, habitat degradation and destruction, alien invasive species, and hydromorphological pressures. On top of these direct stressors, the effects of global processes like environmental and climate change must be considered. The intricate and interconnected nature of various stressors affecting streams has made it challenging to formulate effective policies and management strategies. As a result, restoration efforts have not always been successful in creating a large-scale shift towards a better ecological status. In order to achieve an improved status in these systems, situation-specific management strategies tailored to specific stressor combinations may be needed. In this paper, we examine the potential of introducing native submerged macrophyte species to advance the restoration of stream ecosystems. Through successful introductions, we anticipate positive ecological outcomes, including enhanced water quality and increased biodiversity. This research is significant, as the potential success in restoring stream biodiversity not only represents progress in ecological understanding but also offers valuable insights for future restoration and management strategies for these vital ecosystems.

18.
Biol Rev Camb Philos Soc ; 99(1): 313-327, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37813384

RESUMO

Many fish species depend on migration for various parts of their life cycle. Well-known examples include diadromous fish such as salmon and eels that need both fresh water and salt water to complete their life cycle. Migration also occurs within species that depend only on fresh water. In recent decades, anthropogenic pressures on freshwater systems have increased greatly, and have resulted, among other effects, in drastic habitat fragmentation. Fishways have been developed to mitigate the resulting habitat fragmentation, but these are not always effective. To improve fishway efficiency, the variety of navigation cues used by fish must be better understood: fish use a multitude of sensory inputs ranging from flow variables to olfactory cues. The reaction of a fish is highly dependent on the intensity of the cue, the fish species involved, and individual traits. Recently developed monitoring technologies allow us to gain insights into different combinations of environmental and physiological conditions. By combining fish behavioural models with environmental models, interactions among these components can be investigated. Several methods can be used to analyse fish migration, with state-space models, hidden Markov models, and individual-based models potentially being the most relevant since they can use individual data and can tie them to explicit spatial locations within the considered system. The aim of this review is to analyse the navigational cues used by fish and the models that can be applied to gather knowledge on these processes. Such knowledge could greatly improve the design and operation of fishways for a wider range of fish species and conditions.


Assuntos
Sinais (Psicologia) , Peixes , Animais , Peixes/fisiologia , Água Doce , Ecossistema , Fenótipo
19.
PLoS One ; 19(3): e0299246, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38484016

RESUMO

Batrachochytrium dendrobatidis (Bd) is a lethal fungal species that parasitizes vertebrates and is associated with the worldwide decline of amphibian populations. The development of sensitive, rapid detection methods, particularly DNA-based techniques, is critical for effective management strategies. This study evaluates the efficacy of DNA extraction and a portable PCR device in a mountable field laboratory setup for detecting Bd near the habitats of three critically endangered Atelopus toad species in Ecuador. We collected skin swabs from Atelopus balios, A. nanay, and A. bomolochos, and environmental DNA (eDNA) samples from streams in Andean and coastal regions of Ecuador. For eDNA, a comparison was made with duplicates of the samples that were processed in the field and in a standard university laboratory. Our findings revealed Bd detection in eDNA and swabs from 6 of 12 water samples and 10 of 12 amphibian swab samples. The eDNA results obtained in the field laboratory were concordant with those obtained under campus laboratory conditions. These findings highlight the potential of field DNA-based monitoring techniques for detecting Bd in amphibian populations and their aquatic habitats, particularly in remote areas. Furthermore, this research aligns with the National Action Plan for the Conservation of Ecuadorian Amphibians and contributes to the global effort to control this invasive and deadly fungus.


Assuntos
Quitridiomicetos , DNA Ambiental , Humanos , Animais , Batrachochytrium/genética , Equador , Quitridiomicetos/genética , Bufonidae/genética , Anfíbios/microbiologia , DNA , Ecossistema
20.
Nat Ecol Evol ; 8(6): 1098-1108, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38773326

RESUMO

Inland navigation in Europe is proposed to increase in the coming years, being promoted as a low-carbon form of transport. However, we currently lack knowledge on how this would impact biodiversity at large scales and interact with existing stressors. Here we addressed this knowledge gap by analysing fish and macroinvertebrate community time series across large European rivers comprising 19,592 observations from 4,049 sampling sites spanning the past 32 years. We found ship traffic to be associated with biodiversity declines, that is, loss of fish and macroinvertebrate taxonomic richness, diversity and trait richness. Ship traffic was also associated with increases in taxonomic evenness, which, in concert with richness decreases, was attributed to losses in rare taxa. Ship traffic was especially harmful for benthic taxa and those preferring slow flows. These effects often depended on local land use and riparian degradation. In fish, negative impacts of shipping were highest in urban and agricultural landscapes. Regarding navigation infrastructure, the negative impact of channelization on macroinvertebrates was evident only when riparian degradation was also high. Our results demonstrate the risk of increasing inland navigation on freshwater biodiversity. Integrative waterway management accounting for riparian habitats and landscape characteristics could help to mitigate these impacts.


Assuntos
Biodiversidade , Peixes , Invertebrados , Animais , Europa (Continente) , Invertebrados/fisiologia , Rios , Água Doce , Conservação dos Recursos Naturais , Navios
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