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1.
J Environ Manage ; 276: 111293, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33007713

RESUMO

Sustainable land management practices can be suitable vehicles to simultaneously address the causes and consequences of land degradation, desertification, and climate change in land managed systems. Here, we assess the potential of a variety of sustainable land management practices that, beyond addressing specific and local issues, assist in tackling Mediterranean Basin-wide land-use challenges. With this work, we aim to highlight those options that simultaneously promote local and regional Basin-wide adaptation. To do that, we developed a novel multi-objective assessment that evaluates the effectiveness of 104 practices adopted within the Mediterranean Basin and documented in the World Overview of Conservation Approaches and Technologies global database. Results indicate that agroforestry and green covers in perennial woody crops can promote multiple ecosystem services while addressing climate change adaptation. We further argue that these two practices together with reforestation, assist in regulating the hydrological cycle of the Basin and in maintaining its multifunctional landscape. Lastly, we reflect on potential biophysical and socio-economic barriers and opportunities associated with the implementation of the three practices. Our approach provides a Basin-wide integrated view that facilitates the coordination of sustainable management strategies across the Mediterranean region.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Agricultura , Mudança Climática , Humanos , Região do Mediterrâneo
2.
Aquat Toxicol ; 228: 105632, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33010638

RESUMO

An experiment was carried out using microcosms to evaluate the impact of the fluoroquinolone antibiotic on nematode trophic groups structure and bacterial abundance. Sediment samples were experimentally enriched with four increasing doses of ciprofloxacin [D1 (50 ppm), D2 (100 ppm), D3 (200 ppm) and D4 (500 ppm)] and compared to non-enriched sediments (used as control). Ciprofloxacin changed the trophic composition of nematodes taxa where the relative abundance of microvores (M), epigrowth feeders (EF) and ciliate consumers (CF), raised in a control microcosm, was highly affected and significantly decreased in response to the increasing doses. Nevertheless, the abundance of deposit feeders (DF), optional predators (FP) and exclusive predators (Pr) showed a significant increase. Results from the multivariate analysis showed a clear impact of this antibiotic on nematode trophic assemblages. Microcosms treated with the three highest doses [D2, D3 and D4] were different from the control. The exceptions were those treated with the lowest dose, D1, and which were grouped with the control. The SIMPER analysis results showed that the average dissimilarity continuously increased in the treated microcosms compared to the control. Furthermore, our results have shown that ciprofloxacin also leads to a significant decrease in bacterial density with the highest dose, which could explain the results obtained for nematode trophic groups distribution. Thus, the bacteriophages nematodes only use bacteria as a nutrition source and the lack or presence in small quantity of this food could induce a decrease in their abundance as well as changing of nematodes groups repartition. Our work demonstrates that the nematode responses were dependent on sediment enrichment with ciprofloxacin and opens new perspectives on the potential impact of antibiotics on functional nematode diversity.


Assuntos
Antibacterianos/toxicidade , Organismos Aquáticos/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Ciprofloxacino/toxicidade , Ecossistema , Sedimentos Geológicos/química , Nematoides/fisiologia , Animais , Bactérias/efeitos dos fármacos , Análise por Conglomerados , Geografia , Sedimentos Geológicos/microbiologia , Região do Mediterrâneo , Análise Multivariada , Nematoides/efeitos dos fármacos , Densidade Demográfica , Análise de Componente Principal , Poluentes Químicos da Água/toxicidade
3.
Environ Sci Process Impacts ; 22(11): 2212-2229, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32996961

RESUMO

Fine particle samples were collected during summer at an urban (LIM) and a rural/background (AGM) site of Cyprus. They were analyzed for pinene and isoprene secondary organic aerosol (PSOA-ISOA) tracers, linear dicarboxylic acids (DCAs), hydroxyacids (HAs), aromatic acids (AAs), monocarboxylic acids (MCAs) and levoglucosan by GC/MS with prior 3-step derivatization. DCAs, AAs, MCAs and levoglucosan exhibited significantly higher concentrations (p < 0.05) in LIM, PSOAs and ISOAs in AGM (p < 0.05), whereas mixed trends were found for HAs. Among DCAs, succinic was the most abundant in both sites, accounting for 42.5% and 36.5% of the total DCAs in LIM and AGM respectively, followed by adipic in LIM (20.1%) and azelaic in AGM (22.4%). Malic, phthalic and palmitic acids were the dominant HA, AA and MCA, respectively. Regarding PSOAs, significant differences were observed between the two sites, with the first-generation products accounting for 59.8% of the total measured PSOAs in AGM, but were remarkably lowered (10.3%) in LIM indicating that they were highly oxidized. 2-Methylerythritol was the dominant ISOA tracer in both sites; nevertheless the elevated relative abundance of 2-methylglyceric acid in LIM implies the influences of higher NOx levels. The increased O3 levels observed in AGM appear to have a significant impact on SOA formation. Source apportionment tools employed revealed factors related to secondary formation processes including oxidation of unsaturated fatty acids, pinene, isoprene and anthropogenic VOCs and factors associated with primary sources such as biomass burning, plant emissions and/or cooking and motor exhaust, with noteworthy differences observed between the two areas.


Assuntos
Poluentes Atmosféricos , Material Particulado , Aerossóis/análise , Poluentes Atmosféricos/análise , Região do Mediterrâneo , Oxidantes , Material Particulado/análise
4.
Sci Total Environ ; 741: 140459, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32887020

RESUMO

Climatic extreme events such as droughts (unpredictable), dry periods (predictable) or even flush floods, threaten freshwater ecosystems worldwide. The filtering mechanisms of these events and their strength on communities, however, can be different among regions. While time-for-adaptation theory defines whether or not water scarcity can be considered as disturbance, the stress-dominance theory predicts an increase in importance of environmental filtering and a decrease in the role of biotic interactions in communities with increasing environmental stress. Here, we tested whether environmental filtering (leading to trait convergence) or limiting similarity (leading to trait divergence) is the main assembly rule shaping the structure and trait composition of benthic diatom assemblages in Mediterranean (Portuguese) and continental (Hungarian) temporary and perennial streams. We assumed that the trait composition of diatom assemblages in the two stream types would be less different in the Mediterranean than in the continental region (addressed to time-for-adaptation theory). We also hypothesized that trait composition would be shaped by environmental filtering in the Hungarian streams while by biotic interactions in Portuguese streams (addressed to stress-dominance theory). Our results supported our first hypothesis since traits, which associated primarily to temporary streams were found only in the continental region. Our findings, however, only partially proved the stress-dominance hypothesis. In the continental region, where drying up of streams were induced by unpredictable droughts, biotic interactions were the main assembly rules shaping community structure. In contrast, environmental filtering was nearly as important as limiting similarity in structuring trait composition in the Mediterranean region during the predictable dry phase with no superficial flow. These analyses also highlighted that drought events (both predictable and unpredictable ones) have a complex and strong influence on benthic diatom assemblages resulting even in irreversible changes in trait composition and thereby in ecosystem functioning.


Assuntos
Diatomáceas , Adaptação Fisiológica , Ecossistema , Água Doce , Região do Mediterrâneo
5.
PLoS One ; 15(9): e0238237, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32925932

RESUMO

The objective of this paper is to assess foodstuff storage throughout Recent Prehistory (5600-50 BCE) from the standpoint of the three different types (household, surplus and supra-household) identified in the northeast of the Iberian Peninsula. The volumetric data of the underground silos serves as a proxy to evaluate the link between them and the agricultural systems and technological changes. The study also assesses the ability, and specifically, the will of the ancient communities of the northeastern Iberia to generate domestic and extra-domestic surpluses.


Assuntos
Agricultura/métodos , Características da Família/história , Armazenamento de Alimentos/história , Armazenamento de Alimentos/métodos , Agricultura/estatística & dados numéricos , Armazenamento de Alimentos/normas , História Antiga , História Medieval , Humanos , Região do Mediterrâneo
6.
PLoS One ; 15(9): e0238222, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32936803

RESUMO

The expansion of agriculture is a major driver of biodiversity loss worldwide, through changes generated in the landscape. Despite this, very little is still known about the complex relationships between landscape composition and heterogeneity and plant taxonomical and functional diversity in Mediterranean ecosystems that have been extensively managed during millennia. Although according to the Intermediate Disturbance Hypothesis (IDH) plant richness might peak at intermediate disturbance levels, functional diversity might increase with landscape heterogeneity and decrease with the intensity of disturbance. Here, we evaluated the associations of landscape composition (percentage of crops) and heterogeneity (diversity of land-cover classes) with plant taxonomical diversity (richness, diversity, evenness), local contribution to beta diversity, and functional diversity (functional richness, evenness, divergence and dispersion) in 20 wild Olea europaea communities appearing within agricultural landscapes of Mallorca Island (Western Mediterranean Basin). In accordance with the IDH, we found that overall plant richness peaked at intermediate levels of crops in the landscape, whereas plant evenness showed the opposite pattern, because richness peak was mainly related to an increase in scarce ruderal species. Plant communities surrounded by very heterogeneous landscapes were those contributing the most to beta diversity and showing the highest functional richness and evenness, likely because diverse landscapes favour the colonization of new species and traits into the communities. In addition, landscape heterogeneity decreased functional divergence (i.e., increased trait overlap of dominant species) which may enhance community resilience against disturbances through a higher functional redundancy. However, a large extent of agriculture in the landscape might reduce such resilience, as this disturbance acted as an environmental filter that decreased functional dispersion (i.e, remaining species shared similar traits). Overall, our study highlights the importance of considering several indices of taxonomical and functional diversity to deeply understand the complex relationships between ecosystems functions and landscape context.


Assuntos
Agricultura/métodos , Biodiversidade , Conservação dos Recursos Naturais/métodos , Produtos Agrícolas/crescimento & desenvolvimento , Ecossistema , Monitoramento Ambiental/métodos , Plantas/classificação , Humanos , Região do Mediterrâneo
7.
PLoS One ; 15(9): e0238808, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32913356

RESUMO

The presence of airborne cyanobacteria and microalgae as well as their negative impacts on human health have been documented by many researchers worldwide. However, studies on cyanobacteria and microalgae are few compared with those on bacteria and viruses. Research is especially lacking on the presence and taxonomic composition of cyanobacteria and microalgae near economically important water bodies with much tourism, such as the Adriatic Sea region. Here, we present the first characterization of the airborne cyanobacteria and microalgae in this area. Sampling conducted between 11th and 15th June 2017 revealed a total of 15 taxa of airborne cyanobacteria and microalgae. Inhalation of many of the detected taxa, including Synechocystis sp., Synechococcus sp., Bracteacoccus sp., Chlorella sp., Chlorococcum sp., Stichococcus sp., and Amphora sp., poses potential threats to human health. Aside from two green algae, all identified organisms were capable of producing harmful metabolites, including toxins. Moreover, we documented the presence of the cyanobacterium Snowella sp. and the green alga Tetrastrum sp., taxa that had not been previously documented in the atmosphere by other researchers. Our study shows that the Adriatic Sea region seems to be a productive location for future research on airborne cyanobacteria and microalgae in the context of their impacts on human health, especially during the peak of tourism activity.


Assuntos
Microbiologia do Ar , Cianobactérias/isolamento & purificação , Microalgas/isolamento & purificação , Toxinas Bacterianas , Cianobactérias/classificação , Cianobactérias/metabolismo , Humanos , Região do Mediterrâneo , Microalgas/classificação , Microalgas/metabolismo , Saúde Pública , Toxinas Biológicas
8.
Proc Biol Sci ; 287(1935): 20201840, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32962550

RESUMO

Within a local assemblage, ecosystem engineers can have major impacts on population dynamics, community composition and ecosystem functions by transforming or creating new habitats. They act as an ecological filter altering community composition through a set of environmental variables. The impact of ants on their environment has been widely studied, but their multi-component effects (both trophic and non-trophic) have been rarely addressed. We investigated the roles of Messor barbarus, one of the commonest harvester ant species in south-western European Mediterranean grasslands. We analysed soil physico-chemical parameters, above-ground vegetation (e.g. species richness, plant community, micro-local heterogeneity, plant biomass) and above- and below-ground fauna (macrofauna, Collembola, Acari and nematodes). A clear and strong local impact of M. barbarus on soil, vegetation and fauna compartments emerges. The environmental filter is altered by modifications to soil physico-chemical properties, and the biotic filter by changes to plant communities and altered above- and below-ground fauna abundance, occurrence and community structure. The engineering activity of M. barbarus affects not only these separate ecosystem components but also the trophic and non-trophic relationships between them. By altering ecological filters at a local scale, M. barbarus creates habitat heterogeneity that may in turn increase ecological niches in these highly diverse ecosystems.


Assuntos
Formigas , Pradaria , Animais , Biodiversidade , Ecossistema , Região do Mediterrâneo
9.
PLoS One ; 15(8): e0237744, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841246

RESUMO

Both the Mediterranean (MED) species of the Bemisia tabaci whitefly complex and the greenhouse whitefly (Trialeurodes vaporariorum, TV) are important agricultural pests. The two species of whiteflies differ in many aspects such as morphology, geographical distribution, host plant range, plant virus transmission, and resistance to insecticides. However, the molecular basis underlying their differences remains largely unknown. In this study, we analyzed the genetic divergences between the transcriptomes of MED and TV. In total, 2,944 pairs of orthologous genes were identified. The average identity of amino acid sequences between the two species is 93.6%. The average nonsynonymous (Ka) and synonymous (Ks) substitution rates and the ratio of Ka/Ks of the orthologous genes are 0.0389, 2.23 and 0.0204, respectively. The low average Ka/Ks ratio indicates that orthologous genes tend to be under strong purified selection. The most divergent gene classes are related to the metabolisms of xenobiotics, cofactors, vitamins and amino acids, and this divergence may underlie the different biological characteristics between the two species of whiteflies. Genes of differential expression between the two species are enriched in carbohydrate metabolism and regulation of autophagy. These findings provide molecular clues to uncover the biological and molecular differences between the two species of whiteflies.


Assuntos
Produção Agrícola , Genes de Insetos/genética , Especiação Genética , Hemípteros/genética , Proteínas de Insetos/genética , Sequência de Aminoácidos/genética , Substituição de Aminoácidos/genética , Aminoácidos/metabolismo , Animais , Hemípteros/metabolismo , Proteínas de Insetos/metabolismo , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Região do Mediterrâneo , Anotação de Sequência Molecular , RNA-Seq , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Vitaminas/metabolismo , Xenobióticos/metabolismo
10.
East Mediterr Health J ; 26(6): 626-629, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32621492

RESUMO

The COVID-19 pandemic began as a cluster of reported cases of acute respiratory illness in China on 31 December 2019 and went on to spread with exponential growth across the globe. By the time it was characterized as a global pandemic on 11 March 2020, 17 of 22 countries in the Eastern Mediterranean Region (EMR) had reports of infected persons. EMR countries are particularly susceptible to such outbreaks due to the presence of globally interconnected markets; complex emergencies in more than half of the countries; religious mass gatherings that draw tens of millions of pilgrims annually; and variation in emergency care systems capacity and health systems performance within and between countries.


Assuntos
Infecções por Coronavirus/terapia , Serviços Médicos de Emergência/organização & administração , Serviço Hospitalar de Emergência/organização & administração , Epidemiologia/educação , Cooperação Internacional , Pneumonia Viral/terapia , Saúde Pública/educação , Betacoronavirus , Infecções por Coronavirus/epidemiologia , Política de Saúde , Acesso aos Serviços de Saúde , Humanos , Região do Mediterrâneo/epidemiologia , Pandemias , Pneumonia Viral/epidemiologia , Prática de Saúde Pública , Organização Mundial da Saúde
13.
Proc Natl Acad Sci U S A ; 117(29): 17056-17062, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32601181

RESUMO

Climate change causes changes in the timing of life cycle events across all trophic groups. Spring phenology has mostly advanced, but large, unexplained, variations are present between and within species. Each spring, migratory birds travel tens to tens of thousands of kilometers from their wintering to their breeding grounds. For most populations, large uncertainties remain on their exact locations outside the breeding area, and the time spent there or during migration. Assessing climate (change) effects on avian migration phenology has consequently been difficult due to spatial and temporal uncertainties in the weather potentially affecting migration timing. Here, we show for six trans-Saharan long-distance migrants that weather at the wintering and stopover grounds almost entirely (∼80%) explains interannual variation in spring migration phenology. Importantly, our spatiotemporal approach also allows for the systematic exclusion of influences at other locations and times. While increased spring temperatures did contribute strongly to the observed spring migration advancements over the 55-y study period, improvements in wind conditions, especially in the Maghreb and Mediterranean, have allowed even stronger advancements. Flexibility in spring migration timing of long-distance migrants to exogenous factors has been consistently underestimated due to mismatches in space, scale, time, and weather variable type.


Assuntos
Migração Animal/fisiologia , Aves/fisiologia , Estações do Ano , Tempo (Meteorologia) , África , Animais , Regiões Árticas , Evolução Biológica , Mudança Climática , Região do Mediterrâneo
14.
East Mediterr Health J ; 26(5): 492-494, 2020 May 21.
Artigo em Inglês | MEDLINE | ID: covidwho-600973

RESUMO

The coronavirus disease 2019 (COVID-19) outbreak that began in Wuhan, Hubei Province, China in late 2019 has spread globally within a few months. The Director General of the World Health Organization (WHO) declared the COVID-19 outbreak to be a public health emergency of international concern (PHEIC) after the second meeting of the IHR (2005) Emergency Committee on 30 January 2020. On 12 March 2020, the outbreak of COVID-19 was characterized as a pandemic.


Assuntos
Controle de Doenças Transmissíveis/métodos , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Betacoronavirus , Ensaios Clínicos como Assunto , Controle de Doenças Transmissíveis/economia , Congressos como Assunto , Surtos de Doenças , Financiamento Governamental , Humanos , Região do Mediterrâneo/epidemiologia , Pandemias , Pneumonia Viral , Organização Mundial da Saúde
15.
East Mediterr Health J ; 26(5): 492-494, 2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32538438

RESUMO

The coronavirus disease 2019 (COVID-19) outbreak that began in Wuhan, Hubei Province, China in late 2019 has spread globally within a few months. The Director General of the World Health Organization (WHO) declared the COVID-19 outbreak to be a public health emergency of international concern (PHEIC) after the second meeting of the IHR (2005) Emergency Committee on 30 January 2020. On 12 March 2020, the outbreak of COVID-19 was characterized as a pandemic.


Assuntos
Controle de Doenças Transmissíveis/métodos , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Betacoronavirus , Ensaios Clínicos como Assunto , Controle de Doenças Transmissíveis/economia , Congressos como Assunto , Surtos de Doenças , Financiamento Governamental , Humanos , Região do Mediterrâneo/epidemiologia , Pandemias , Pneumonia Viral , Organização Mundial da Saúde
16.
PLoS One ; 15(6): e0230768, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32555581

RESUMO

Relationships between environmental factors and oscillations in jellyfish abundance, especially in the early life stages, could help to interpret past increases and also predict scenarios in a changing future. For the first time, we present cubozoan spatial and temporal distributions in the earliest stages and their relationships with different factors. Abundances of Carybdea marsupialis medusae showed high interannual variability from 2008 to 2014 along the Dénia coast (SE Spain, W Mediterranean). During 2015, samples were collected from 11 beaches along 17 km of coastline, 8 times from January to November in order to determine the effects of environmental factors on the distribution of juvenile C. marsupialis. Juveniles (≤ 15 mm diagonal bell width) were present from May to July, with more sampled near shore (0-15 m). Most of them occurred in June when their numbers were unequal among beaches (average 0.05 ind m-3, maximum 6.71 ind m-3). We tested distributions of juveniles over time and space versus temperature, salinity, nutrients (N, P and Si), chlorophyll-a (Chl-a), and zooplankton abundance. Temperature and cladocerans (zooplankton group) were significantly positively correlated with juvenile distribution, whereas Chl-a concentration was weakly negative. By contrast, in 2014, high productivity areas (Chl-a and zooplankton) overlapped the maximum adult abundance (5.2 ind m-3). The distribution of juveniles during 2015 did not spatially coincide with the areas where ripe adults were located the previous year, suggesting that juveniles drift with the currents upon release from the cubopolyps. Our results yield important insights into the complexity of cubozoan distributions.


Assuntos
Cubomedusas , Meio Ambiente , Animais , Região do Mediterrâneo , Análise Espaço-Temporal
17.
J Infect Public Health ; 13(10): 1367-1372, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32586684

RESUMO

In December 2019, a cluster of atypical Pneumonia cases in Wuhan, China were reported to the World Health Organization (WHO). Later, those cases were attributed to a novel respiratory virus currently known as COVID-19. The infection is affecting every continent. It was characterized by WHO as a global pandemic on 11 March 2020. Countries worldwide are implementing various preventive measures to contain the spread of the infection such as travel and trade restrictions, closure of educational institutions and shops, and some took more strict measures such as imposing curfew. WHO is emphasizing the importance of early detection of cases, contact tracing, risk communications, implementing multisectoral approach in order to combat COVID-19 infection. Countries should provide the public with accurate, transparent information about the local and global situation of this escalating infection. Much uncertainty still surrounds this viral infection, its modes of transmission and dynamics. Epidemiological investigations particularly for the first few cases of COVID-19 infection are critical to expand our knowledge about this evolving pandemic. In this review we summarized the data available about the first few cases and fatalities of COVID-19 infection up to 18 March 2020 across Eastern Mediterranean Region of the World Health Organization. such data were only available in websites of ministries of health of the targeted countries, WHO situational reports, online newspapers, and other media channels and this gave us an idea about the amount and type of data available for the public regarding this evolving infection.


Assuntos
Infecções por Coronavirus/epidemiologia , Pandemias , Pneumonia Viral/epidemiologia , África Oriental/epidemiologia , África do Norte/epidemiologia , Betacoronavirus , Humanos , Região do Mediterrâneo/epidemiologia , Oriente Médio/epidemiologia , Paquistão/epidemiologia , Organização Mundial da Saúde
18.
Proc Natl Acad Sci U S A ; 117(27): 15443-15449, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32571905

RESUMO

The assassination of Julius Caesar in 44 BCE triggered a power struggle that ultimately ended the Roman Republic and, eventually, the Ptolemaic Kingdom, leading to the rise of the Roman Empire. Climate proxies and written documents indicate that this struggle occurred during a period of unusually inclement weather, famine, and disease in the Mediterranean region; historians have previously speculated that a large volcanic eruption of unknown origin was the most likely cause. Here we show using well-dated volcanic fallout records in six Arctic ice cores that one of the largest volcanic eruptions of the past 2,500 y occurred in early 43 BCE, with distinct geochemistry of tephra deposited during the event identifying the Okmok volcano in Alaska as the source. Climate proxy records show that 43 and 42 BCE were among the coldest years of recent millennia in the Northern Hemisphere at the start of one of the coldest decades. Earth system modeling suggests that radiative forcing from this massive, high-latitude eruption led to pronounced changes in hydroclimate, including seasonal temperatures in specific Mediterranean regions as much as 7 °C below normal during the 2 y period following the eruption and unusually wet conditions. While it is difficult to establish direct causal linkages to thinly documented historical events, the wet and very cold conditions from this massive eruption on the opposite side of Earth probably resulted in crop failures, famine, and disease, exacerbating social unrest and contributing to political realignments throughout the Mediterranean region at this critical juncture of Western civilization.


Assuntos
Mudança Climática/história , Clima Frio/efeitos adversos , Desastres/história , Mundo Romano/história , Erupções Vulcânicas/efeitos adversos , Alaska , Clima , Produtos Agrícolas/história , Fome Epidêmica/história , História Antiga , Camada de Gelo , Região do Mediterrâneo , Política , Erupções Vulcânicas/história
19.
PLoS Negl Trop Dis ; 14(5): e0008284, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32357192

RESUMO

BACKGROUND: Diflubenzuron (DFB) is one of the most used insecticides in mosquito larval control including that of Culex pipiens, the proven vector of the recent West Nile Virus epidemics in Europe. Two mutations (I1043L and I1043M) in the chitin synthase (CHS) putative binding site of DFB have been previously reported in Cx. pipiens from Italy and associated with high levels of resistance against this larvicide. METHODOLOGY/PRINCIPAL FINDINGS: Here we report the identification of a third mutation at the same I1043 position of the CHS gene resulting in the substitution of Isoleucine to Phenylalanine (I1043F). This mutation has also been found in agricultural pests and has been functionally validated with genome editing in Drosophila, showing to confer striking levels (>15,000 fold) of DFB resistance. The frequency of the I1043F mutation was found to be substantially higher in Cx. pipiens mosquitoes surviving DFB doses largely exceeding the recommended field dose, raising concerns about the future efficient use of this insecticide. We monitored the presence and frequency of DFB mutations in Cx. pipiens mosquitoes from several Mediterranean countries, including Italy, France, Greece, Portugal and Israel. Among the Cx. pipiens populations collected in Northern Italy all but one had at least one of the three DFB mutations at allele frequencies reaching 93.3% for the I1043M, 64.8% for the I1043L and 10% for the I1043F. The newly reported I1043F mutation was also identified in two heterozygote individuals from France (4.2% allelic frequency). In contrast to Italy and France, no DFB resistant mutations were identified in the Cx. pipiens mosquitoes sampled from Greece, Portugal and Israel. CONCLUSIONS/SIGNIFICANCE: The findings of our study are of major concern for mosquito control programs in Europe, that rely on the use of a limited number of available larvicides, and highlight the necessity for the development of appropriate Insecticide Resistance Management (IRM) programs, to ensure the sustainable use of DFB.


Assuntos
Quitina Sintase/genética , Culex/enzimologia , Diflubenzuron/farmacologia , Proteínas de Insetos/genética , Resistência a Inseticidas , Inseticidas/farmacologia , Mutação Puntual , Animais , Culex/efeitos dos fármacos , Culex/genética , Região do Mediterrâneo , Mutação de Sentido Incorreto
20.
Sci Total Environ ; 730: 139182, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32402978

RESUMO

The objectives of this research were to assess the physical properties of six different growing substrate mixtures destined for roof gardens and determine the influence of these substrates on the morphology, physiology, growth and flower quality of pansy (Viola × wittrockiana), Madagascar periwinkle (Catharanthus roseus), and Pavia lily (Longiflorum×Asiatic lilies (Lilium) 'Pavia'). Six green roof growing substrate mixtures (by volume) were used [T1: coarse tuff+fine tuff+cocopeat (5:1:4), T2:coarse tuff+medium tuff+fine tuff+cocopeat (5:5:2:8), T3: medium tuff+fine tuff+cocopeat (5:1:4), T4:medium tuff+fine tuff + peat moss (5:1:4), T5: perlite+medium tuff+fine tuff+cocopeat (5:5:2:8), and T6: lightweight expandable clay aggregates+fine tuff+cocopeat (5:1:4)]. The T6 (LECA-cocopeat) had the lowest weight at field capacity and good aeration and WHC to sustain optimal plant growth. Medium tuff-peat moss (T4) produced the highest pansy flowers number per plants. However, peat moss (T4) has been identified by environmentalists as an unsustainable media. LECA-cocopeat (T6) had a higher number of lily flowers and leaf area than T1-T4. The cost of the LECA substrate ($US 215 m-3, T6) is extremely higher than that of volcanic tuff ($US 36 m-3, T1-T4), and perlite ($US 100 m-3, T5). Overall, T6 can be an ideal option in terms of physical properties of growing substrate and flower quality but it might not be the best option for green roofs when cost is the primary concern. In addition, certain growing substrates could be used to satisfy specific growing requirements without sacrificing performance. For example, the combination of medium tuff and peat moss (T4) produced the highest pansy flower numbers per plant but required a longer period to flower (95 days). So, this growing substrate could be used where plentiful blooms are desired and the time to bloom is not a concern.


Assuntos
Desenvolvimento Vegetal , Plantas , Flores , Região do Mediterrâneo , Folhas de Planta
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