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1.
Data Brief ; 54: 110449, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38711741

RESUMO

In the last few decades, perennial mountain streams are becoming increasingly intermittent, due to global climate change and anthropogenic pressures. This phenomenon leads to negative effects on benthic communities' biodiversity and river ecosystems functionality. However, the impact of flow intermittency in previously perennial Alpine streams is still poorly investigated. This dataset consists of all the data collected during a spring sampling campaign performed in April-May 2017 along 13 mountain streams located in the SW Italian Alps. These watercourses have been selected because it was possible to identify two different sampling sites: one perennial, where water has always been flowing throughout the years, and one intermittent, which showed flowing water during the sampling campaign but, in the last decade, has experienced summer dry phases. All the sites have been characterized defining the microhabitats in which samples were retrieved, and physico-chemical data were collected at each site. Biological sampling included benthic macroinvertebrates and diatoms. Therefore, the present dataset offers various biological, ecological and physico-chemical information regarding Alpine streams which have recently become intermittent. Potentially, it could be used for comparisons with different benthic communities present in mountain rivers worldwide which are facing drying events too. The broad range of information present in this dataset offers the possibility to examine only the perennial sites themselves, as an example of good river functionality due to continuous flowing water, or only the intermittent ones, to better understand the effects of drying events on these peculiar ecosystems.

2.
Sci Total Environ ; 912: 169444, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38114027

RESUMO

The identification of ecologically sound thresholds represents an important step toward improving the ecological status of rivers through appropriate measures to contain nutrient loads. The aim of the present study was to estimate phosphorus and nitrogen concentrations compatible with the achievement of the "good" ecological status of rivers from data collected in the Po River District, the largest hydrographic system in Italy. For this purpose, relationships between the diatom index used in Italy for the national assessment of the stream ecological status, the ICMi (Intercalibration Common Metric index), and total phosphorus and nitrate concentrations were analyzed using monitoring data collected between 2009 and 2019. The Po River Basin encompasses five distinct river types, from Alpine to Mediterranean to Lowlands, characterized by different anthropogenic pressures and water quality. Through regression analysis between the ICMi and nutrient concentrations, we estimated ranges of the latter values corresponding to a "good" ecological status for each river type. The resulting thresholds are far more stringent than the limits set by the Italian legislation for water quality classification. This is particularly true for total phosphorus, whose threshold value should be roughly halved for all river types. For nitrates, the results are more differentiated according to river type: the estimated thresholds are much more stringent than those currently in use for siliceous Alpine and Mediterranean rivers. Moreover, the availability of such a large database allowed also to assess the influence of one nutrient over the other on the diatom community and to highlight some critical issues in the formulation of ICMi for Mediterranean rivers.

3.
Sci Total Environ ; 762: 143090, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33131853

RESUMO

Over the last decades, the combined effects of global climate changes and severe land use modifications have been exacerbating river hydrological alterations and habitat fragmentation in many Mediterranean rivers. This trend is predicted to intensify, with expected significant impacts on taxonomic and functional diversity of benthic communities in the next future. By comparing perennial and intermittent reaches, the present research aims at investigating the role of flow intermittency, driven by the combined effects of climatic variables and land use changes, on benthic diatom communities in Mediterranean streams (NW Italy), by analysing data collected over 11 years. In order to avoid potential confounding effects related to water quality, sites characterized by "poor" or "bad" water quality were excluded a priori. We observed significant differences between permanent and intermittent sections in terms of both climatic variables and land use: higher temperatures and lower precipitations, coupled with an extensive anthropic land use, intensify the natural flow intermittency in intermittent sites. This led to a significant decline in diatom species diversity, at both local and regional scales, and to changes to life history traits. In particular, communities of intermittent reaches were taxonomically and functionally different and less heterogeneous than assemblages characterizing perennial ones, showing higher percentages of small, mainly stalked and pioneer taxa belonging to the low profile guild. Conversely taxa colonizing permanent reaches were bigger, belonging to the high profile guild and able to produce colonies, thus indicating high environmental stability. Our results highlighted how hydrological alterations are profoundly threatening Mediterranean streams and the diatom communities inhabiting them, therefore representing an important benchmark in view of the improvement of biological indices for the assessment of intermittent rivers.


Assuntos
Diatomáceas , Ecossistema , Monitoramento Ambiental , Hidrologia , Itália , Rios
4.
Biology (Basel) ; 9(9)2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32937870

RESUMO

For this study, we measured the concentrations of 23 trace elements (Al, As, Ba, Bi, Cd, Cr, Co, Cu, Fe, Ga, Hg, In, Li, Mn, Mo, Ni, Pb, Se, Sr, Ti, Tl, V, and Zn) in the whole bodies of three functional feeding groups (FFG) (filterers-Hydropsychidae, scrapers-Heptageniidae, and predators-Odonata) of aquatic insects collected from two sites in the Po basin (Po Settimo and Malone Front, Northwest Italy) to determine: (a) how FFG influence trace element accumulations, (b) if scrapers accumulate higher elements compared to the other FFG, since they graze on periphyton, which represents one of the major sinks of metals, and (c) the potential use of macroinvertebrates to assess the bioavailability of trace elements in freshwater. The hierarchical clustering analysis generated three main groups based on trace element concentrations: the most abundant elements were Fe and Al, followed by Sr, In, Zn, V, Mo, and Cu. Tl was below the limit of detection (LOD) in all FFG. Ga was detected only in scrapers from both sites and Hg only in predators from Po Settimo. The principal component analysis showed that concentrations of Al, As, Bi, Cd, Co, Cr, Ga, Fe, In, Mn, Pb, Ni, and Sr were highest in scrapers, suggesting that trace elements accumulate from the ingestion of epilithic periphyton (biofilm). Odonata (predators) accumulate certain elements (Ba, Hg, Li, Se, V, Ti, and Zn) in higher concentrations by food ingestion composed of different aquatic organisms. Differently, Cu and Mo concentrations were the highest in filterers due to their bioavailability in the water column. Non-metric multidimensional scaling clearly differentiated the FFG based on their ability to accumulate trace elements. The findings from this study represent an important step toward the definition of an innovative approach based on trace element accumulation by macroinvertebrates.

5.
J Biol Phys ; 46(1): 1-31, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32180076

RESUMO

In any ecosystem, chaotic situations may arise from equilibrium state for different reasons. To overcome these chaotic situations, sometimes the system itself exhibits some mechanisms of self-adaptability. In this paper, we explore an eco-epidemiological model consisting of three aquatic groups: phytoplankton, zooplankton, and marine free viruses. We assume that the phytoplankton population is infected by external free viruses and zooplankton get affected on consumption of infected phytoplankton; also, the infected phytoplankton do not compete for resources with the susceptible one. In addition, we model a mechanism by which zooplankton recognize and avoid infected phytoplankton, at least when susceptible phytoplankton are present. The zooplankton extinction chance increases on increasing the force of infection or decreasing the intensity of avoidance. Further, when the viral infection triggers chaotic dynamics, high zooplankton avoidance intensity can stabilize again the system. Interestingly, for high avoidance intensity, nutrient enrichment has a destabilizing effect on the system dynamics, which is in line with the paradox of enrichment. Global sensitivity analysis helps to identify the most significant parameters that reduce the infected phytoplankton in the system. Finally, we compare the dynamics of the system by allowing the infected phytoplankton also to share resources with the susceptible phytoplankton. A gradual increase of the virus replication factor turns the system dynamics from chaos to doubling state to limit cycle to stable state and the system finally settles down to the zooplankton-free equilibrium point. Moreover, on increasing the intensity of avoidance, the system shows a transcritical bifurcation from the zooplankton-free equilibrium to the coexistence steady state and remains stable thereafter.


Assuntos
Aprendizagem da Esquiva , Modelos Biológicos , Fitoplâncton/fisiologia , Fitoplâncton/virologia , Zooplâncton/fisiologia , Zooplâncton/virologia , Animais
6.
Environ Monit Assess ; 191(2): 88, 2019 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-30661125

RESUMO

The number of dams is predicted to increase worldwide under the current global change scenario. A major environmental problem associated with dams is the release of large quantities of fine sediment downstream. Therefore, future studies in river conservation will largely be focused on the management of sediments trapped by reservoirs. The aim of this study was to investigate the downstream ecological impacts of sediment flushing from a dam and the effectiveness of artificial flash floods as a recovery strategy. Artificial flash floods have often been employed to remove large amounts of sediment from riverbeds, but their importance in improving the biological quality of lotic environments is almost unknown. We carried out a series of quantitative macroinvertebrate samplings over a 2-year period that started before sediment release and included the artificial flushing events. We characterized the macroinvertebrate community in its structural and functional aspects and tested the performance of two biomonitoring indexes, comparing their diagnostic ability. Our results demonstrated that sediment flushing significantly altered the structure and composition of benthic communities for more than 1 year. Flash floods exacerbated the overall biological quality, but we believe that this treatment was useful because, by removing large amounts of sediment, the biological recovery process was accelerated. Finally, regarding the water quality assessment, we found that the biomonitoring index for siltation, composed of a selection of taxonomical and functional metrics, was more reliable than the generic one.


Assuntos
Monitoramento Ambiental/métodos , Inundações , Sedimentos Geológicos/química , Invertebrados/classificação , Movimentos da Água , Animais , Rios/química , Qualidade da Água
7.
Psychogeriatrics ; 19(1): 55-64, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30221438

RESUMO

AIM: The aim of this study was to verify dog-assisted therapy's effectiveness on depression and anxiety in institutionalized elderly. Patients' illness perception was examined to identify core beliefs regarding mood, personal control, and illness coherence because they can affect treatment compliance. Subjective perception of pain, social interaction, and setting-bound observable variables were also studied. METHODS: This study involved a randomized sample of institutionalized patients 65 years of age and older; the treatment group had 17 subjects and the control group had 14 subjects. All patients were administered the Mini-Mental State Examination, 15-item Geriatric Depression Scale, Positive and Negative Affect Schedule, Generalized Anxiety Disorder 7, Illness Perception Questionnaire, and Numeric Pain Rating Scale. Intra- and inter-group data analysis was performed before and after treatment. Over the course of 10 weeks, patients participated in individual 30-min sessions. An observational methodology was developed to record verbal and non-verbal interactions between the elderly, the dog, and the dog handler. RESULTS: A large effect size and a statistically significant decrease in 15-item Geriatric Depression Scale scores were identified in the treatment group. No significant differences were detected in the Generalized Anxiety Disorder 7, Positive and Negative Affect Schedule, and Numeric Pain Rating Scale. However, the Positive and Negative Affect Schedule and the Numeric Pain Rating Scale showed a moderate decrease. The Illness Perception Questionnaire's timeline (acute/chronic) and treatment control subscales showed a clinically relevant, large effect size. CONCLUSIONS: Dog-assisted therapy has proved to be effective in reducing symptoms of depression in institutionalized elderly. The increase in verbal interactions with the handlers throughout the study suggests the dog acts as a facilitator of social interaction, eliciting positive emotional responses. Dog-assisted therapy shows promising results in the perception of illness timeline and treatment control, indicating potential enhancement of the sense of treatment-related empowerment. However, further study is required.


Assuntos
Terapia Assistida com Animais/métodos , Transtornos de Ansiedade/terapia , Atitude Frente a Saúde , Transtorno Depressivo/terapia , Avaliação Geriátrica/estatística & dados numéricos , Institucionalização , Idoso , Transtornos de Ansiedade/psicologia , Transtorno Depressivo/psicologia , Feminino , Avaliação Geriátrica/métodos , Humanos , Itália , Masculino , Testes Neuropsicológicos , Inquéritos e Questionários , Resultado do Tratamento
8.
Sci Total Environ ; 592: 503-511, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28314608

RESUMO

Clogging, the streambed colmation by fine sediments, is an important widespread source of impact affecting freshwaters. Alterations in stream morphology and hydrology, added to the effects of global climate change, are responsible for this phenomenon, that is particularly pernicious in mountainous lotic systems naturally characterized by coarse substrates. Among the studies investigating this issue some were descriptive, while others used artificial substrates to compare ongoing fine sediment accumulation and macroinvertebrate assemblage recruitment. Other studies used from the outset artificial substrates arranged with different levels of clogging. Our study fits into this line, but adding an innovative element simulating different availability of coarse particulate organic matter, i.e. the main trophic input in low-order, mountainous stream. To investigate how clogging and CPOM can influence macroinvertebrate communities, we placed 135 artificial substrates in the upper Po river (NW Italy). We set up a three way factorial design with three different levels of sedimentation and terrestrial leaf material. Artificial substrates were removed on three different dates. Benthic invertebrates were identified and classified according to their bio-ecological traits. We also measured macroinvertebrate dry mass and CPOM degradation in the different trap types. Our findings show that clogging acts as a selective filter influencing taxa richness, density, functional composition and biomass of benthic assemblage. Moreover, fine sediments affect the energetic dynamics in the river ecosystem, decreasing the mass loss rate of terrestrial leaves. Interestingly, our results clearly demonstrate that high availability of CPOM can buffer the negative effect of clogging, suggesting that an adequate input of allochthonous organic matter may lessen the impact of fine sediment deposition. Because land use transformation and removal of wooded riparian areas increase clogging and simultaneously reduces the input of CPOM, our findings stress the importance to include the management of river basins in the conservation strategies of mountainous streams.

9.
J Adolesc Young Adult Oncol ; 6(2): 377-380, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28112547

RESUMO

This study focuses on body image discomfort (BID) of 50 adolescent and young adult (AYA) hematologic cancer survivors (age range 15-23; 52% males). The study results were obtained through data from a self-report questionnaire: the Body Uneasiness Test. Findings differed according to gender: a greater proportion of females were in the Risk category of impaired body image than males (χ2 = 5.258, p < 0.05). No significant body image differences were found according to the type of diagnosis or to the length of survival. To manage survivors' BIDs and to improve their quality of life, assessing BID in AYA cancer survivors is important for identifying those who might be in need of additional supportive care or a program.


Assuntos
Transtornos Dismórficos Corporais/psicologia , Imagem Corporal/psicologia , Sobreviventes de Câncer/psicologia , Neoplasias Hematológicas , Qualidade de Vida , Adolescente , Feminino , Doença de Hodgkin , Humanos , Linfoma não Hodgkin , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras , Adulto Jovem
10.
Glob Chang Biol ; 23(7): 2554-2564, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27997069

RESUMO

The increasing conversion of agricultural and natural areas to human-dominated urban landscapes is predicted to lead to a major decline in biodiversity worldwide. Two conditions that typically differ between urban environments and the surrounding landscape are increased temperature, and high patch isolation and habitat turnover rates. However, the extent and spatial scale at which these altered conditions shape biotic communities through selection and/or filtering on species traits are currently poorly understood. We sampled carabid beetles at 81 sites in Belgium using a hierarchically nested sampling design wherein three local-scale (200 × 200 m) urbanization levels were repeatedly sampled across three landscape-scale (3 × 3 km) urbanization levels. First, we showed that communities sampled in the most urbanized locations and landscapes displayed a distinct species composition at both local and landscape scale. Second, we related community means of species-specific thermal preferences and dispersal capacity (based on European distribution and wing morphology, respectively) to the urbanization gradients. We showed that urban communities consisted on average of species with a preference for higher temperatures and with better dispersal capacities compared to rural communities. These shifts were caused by an increased number of species tolerating higher temperatures, a decreased richness of species with low thermal preference, and an almost complete depletion of species with very low-dispersal capacity in the most urbanized localities. Effects of urbanization were most clearly detected at the local scale, although more subtle effects could also be found at the scale of entire landscapes. Our results demonstrate that urbanization may fundamentally and consistently alter species composition by exerting a strong filtering effect on species dispersal characteristics and favouring replacement by warm-dwelling species.


Assuntos
Biodiversidade , Ecossistema , Urbanização , Animais , Bélgica , Besouros , Humanos
11.
Sci Total Environ ; 569-570: 40-45, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27328398

RESUMO

Liquid digestate is considered as an important by-product of anaerobic digestion of agriculture wastes. Currently, it is very often directly spread on local agricultural land. Yet recently concerns on its environmental risk of this processing has begun to rise. On the other hand, investigations on the effectiveness of microalgae for wastewater treatment have started to consider also this complex matrix. In this study, we cultured the green alga Chlorella vulgaris in diluted digestate coming from the anaerobic digestion of pig slurry and corn, with the aim to significantly reduce its toxicity and its very high nutrient concentration. For this purpose, a battery of toxicity tests composed of four acute and two chronic bioassays was applied after the alga cultivation. Results were compared with those obtained in the initial characterization of the digestate. Results show that highly diluted piggery digestate can be a suitable medium for culturing microalgae, as we obtained a high removal efficiency (>90%) for ammonia, total nitrogen and phosphate, though after a few days phosphorus limitation occurred. Toxicity was significantly reduced for all the organisms tested. Possible solutions for optimizing this approach avoiding high dilution rates are discussed.


Assuntos
Esterco/análise , Microalgas/crescimento & desenvolvimento , Microalgas/metabolismo , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/análise , Animais , Biodegradação Ambiental , Chlorella vulgaris/crescimento & desenvolvimento , Chlorella vulgaris/metabolismo , Medição de Risco , Sus scrofa , Testes de Toxicidade
12.
Sci Total Environ ; 551-552: 127-32, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26874769

RESUMO

Digestate represents a precious by-product in particular in agriculture, however its impact on the environment and human health is still unexplored. In this work, the toxicity of a pig slurry digestate was assessed through 7 ecotoxicity tests and considering 10 different endpoints. Besides, a synthetic index was applied to the outputs of the battery of tests for the environmental risk assessment, in order to evaluate the opportunity to use directly this kind of digestate in agriculture or to introduce an additional treatment. All the organisms were sensitive to digestate toxicity (EC50 ranged from 14.22% for Cucumissativus to 0.77% for Raphidocelis subcapitata). The physical-chemical features at the base of this toxicity seem to be the high content of ammonium, salinity, COD, phosphate and colour. The synthetic index showed that the digestate was very toxic and associated to an extremely high environmental risk. Thus, a pre-treatment is needed to reduce its toxicity and environmental impact, whatever could be its exploitation.


Assuntos
Esterco , Eliminação de Resíduos Líquidos/métodos , Agricultura , Animais , Eliminação de Resíduos , Medição de Risco , Sus scrofa , Suínos , Testes de Toxicidade
13.
Chemosphere ; 92(6): 738-44, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23706373

RESUMO

In this paper three microalgae strains (Neochloris oleoabundans, Chlorella vulgaris and Scenedesmus obliquus) were cultivated on an agro-zootechnical digestate in comparable conditions. The material used as growth media was obtained from a pilot plant anaerobic digestor used to digest several mixes of cattle slurry and raw cheese whey. The main aims were to compare the algae growth, their tolerance with respect to the various dilutions of digestate, their nutrient removal efficiency and their role in the transformation of nitrogen compounds. C. vulgaris presented the highest elimination capacity of ammonium in 1:10 digestate sample; it was also observed that only 4% of ammonia was removed with stripping, microalgal and bacterial consortium recovered the remaining 96%. The three strains almost completely removed different nitrogen forms and phosphate in 11d. The results show that microalgal biomass production offers real opportunities for addressing issues such CO2 sequestration, biofuel production and wastewater treatment.


Assuntos
Clorófitas/metabolismo , Microalgas/metabolismo , Compostos de Nitrogênio/isolamento & purificação , Compostos de Nitrogênio/metabolismo , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/análise , Animais , Biodegradação Ambiental , Bovinos , Queijo , Clorófitas/crescimento & desenvolvimento , Microalgas/crescimento & desenvolvimento
14.
Rev. biol. trop ; 50(3/4): 1125-1131, sept.-dic. 2002. ilus, tab, graf
Artigo em Inglês | LILACS | ID: lil-350094

RESUMO

Biotic indexes are one of several types of measures that are routinely used in biological monitoring in temperate streams and offer interesting possibilities to assess the environmental quality of rivers in the neotropics. Macroinvertebrate communities of seven southeastern Nicaraguan streams were monitored and seven ecological indexes were applied. The results suggest that information from the Indice Biótico Esteso (I.B.E.) is closely correlated to the results of other methods, but the I.B.E. index is easier to apply as well as avoiding high costs and time-consuming procedures. A calibration of the method is necessary for rapid assessment approaches in the neotropics


Assuntos
Animais , Biomassa , Ecossistema , Monitoramento Ambiental , Invertebrados , Água Doce , Nicarágua
15.
Rev Biol Trop ; 50(3-4): 1125-31, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12947595

RESUMO

Biotic indexes are one of several types of measures that are routinely used in biological monitoring in temperate streams and offer interesting possibilities to assess the environmental quality of rivers in the neotropics. Macroinvertebrate communities of seven southeastern Nicaraguan streams were monitored and seven ecological indexes were applied. The results suggest that information from the Indice Biótico Esteso (I.B.E.) is closely correlated to the results of other methods, but the I.B.E. index is easier to apply as well as avoiding high costs and time-consuming procedures. A calibration of the method is necessary for rapid assessment approaches in the neotropics.


Assuntos
Biomassa , Ecossistema , Monitoramento Ambiental/métodos , Invertebrados , Animais , Água Doce , Nicarágua
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