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2.
Glob Chang Biol ; 26(1): 119-188, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31891233

RESUMO

Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives.


Assuntos
Acesso à Informação , Ecossistema , Biodiversidade , Ecologia , Plantas
3.
Sci Total Environ ; 698: 133960, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31493573

RESUMO

Disentangling the processes that drive plant community assembly is critical for understanding the patterns of plant diversity. We studied how different abiotic and biotic factors shape the interplay between the facets of alpine plant diversity, functional (FD), phylogenetic (PD) and taxonomic diversity (TD), in three different mountain ranges with contrasting evolutionary histories and climate conditions (Pyrenees and Mediterranean-type mountains in central Spain and Chilean Andes). We hypothesized that the causal links vary in strength and sign across regions. We used species inventories, functional trait data, and a phylogeny from 84 plant communities spread throughout three high-mountain alpine grasslands. Structural equation models were used to test our causal hypotheses on the relationships observed between the three diversity facets, and the abiotic (elevation, potential solar radiation and soil total nitrogen) and biotic factors (C-score). Despite our causal model presented a high variability in each mountain range, TD always decreased with increasing elevation (sum of direct and indirect effects). We also found some patterns suggesting that assembly processes could be climatically/biogeographically structured such as the negative relationship between FD and elevation found in Mediterranean mountains and the negative relationship between FD and TD found in both Spanish mountain ranges (independently of their different climates). A remarkable finding of this study is that ecological factors such as soil total nitrogen and elevation indirectly alter the relationships between the diversity facets. Our results suggest that diversity facets are simultaneously affected by different ecological and biogeographical/evolutionary processes, resulting in some general trends but also in parallel idiosyncratic patterns. Our findings highlight that although FD stand out by its explanatory power of community processes, TD and PD provide a complementary and necessary view that should not be disregarded in the attempt to globally explain community assembly processes.


Assuntos
Biodiversidade , Clima , Filogenia , Altitude , Chile , Mudança Climática , Ecologia , Monitoramento Ambiental , Plantas , Solo , Espanha
4.
Huan Jing Ke Xue ; 41(1): 321-329, 2020 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854933

RESUMO

This study analyzes the microbial community and diversity composition of activated sludge in anoxic/oxic (A/O) treatment systems at different operation stages using Illumina MiSeq high-throughput sequencing to investigate the microbial community structure and diversity in activated sludge for starch wastewater treatment. The experimental results showed that the microbial community structure of activated sludge for starch production wastewater treatment in A/O systems was quite stable under the same wastewater condition, and that the dominant bacteria of the activated sludge were Proteobacteria, Bacteroidetes, Chloroflexi, Firmicutes, and Actinobacteria. The most important dominant bacterial group was Proteobacteria (45.66%-66.30%), of which γ-subclass bacteria were the main member and occupied 36.38%-66.65%. The proportion of Sphingobacteria, the main member of the Bacteroidetes, decreased when the sludge settling performance was better, but the proportion of Anaerolineae, the main member of Chloroflexi, increased significantly when the sludge sedimentation performance was better. These changes may have been closely related to the behavior of sludge settleability. There were a large number of functional bacteria in the activated sludge, which played an important role in the degradation of pollutants and in nitrogen and/or phosphorus removal.


Assuntos
Bactérias/classificação , Biodiversidade , Esgotos/microbiologia , Amido , Águas Residuárias/microbiologia , Reatores Biológicos , Purificação da Água
5.
Gut ; 69(1): 92-102, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31003979

RESUMO

OBJECTIVE: Patients with primary sclerosing cholangitis (PSC) were previously shown to display a bacterial gut dysbiosis but fungal microbiota has never been examined in these patients. The aim of this study was to assess the fungal gut microbiota in patients with PSC. DESIGN: We analysed the faecal microbiota of patients with PSC and concomitant IBD (n=27), patients with PSC and no IBD (n=22), patients with IBD and no PSC (n=33) and healthy subjects (n=30). Bacterial and fungal composition of the faecal microbiota was determined using 16S and ITS2 sequencing, respectively. RESULTS: We found that patients with PSC harboured bacterial dysbiosis characterised by a decreased biodiversity, an altered composition and a decreased correlation network density. These alterations of the microbiota were associated with PSC, independently of IBD status. For the first time, we showed that patients with PSC displayed a fungal gut dysbiosis, characterised by a relative increase in biodiversity and an altered composition. Notably, we observed an increased proportion of Exophiala and a decreased proportion of Saccharomyces cerevisiae. Compared with patients with IBD and healthy subjects, the gut microbiota of patients with PSC exhibited a strong disruption in bacteria-fungi correlation network, suggesting an alteration in the interkingdom crosstalk. CONCLUSION: This study demonstrates that bacteria and fungi contribute to gut dysbiosis in PSC.


Assuntos
Colangite Esclerosante/microbiologia , Disbiose/microbiologia , Fungos/isolamento & purificação , Microbioma Gastrointestinal , Adulto , Idoso , Bactérias/classificação , Bactérias/isolamento & purificação , Técnicas de Tipagem Bacteriana/métodos , Biodiversidade , Feminino , Fungos/classificação , Humanos , Doenças Inflamatórias Intestinais/microbiologia , Masculino , Pessoa de Meia-Idade , Técnicas de Tipagem Micológica/métodos , Adulto Jovem
6.
Ecol Lett ; 23(1): 79-87, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31631491

RESUMO

Increases in niche complementarity have been hypothesised to reduce the intensity of interspecific competition within natural forests. In regions currently experiencing potentially enhanced growth under global environmental change, niche complementarity may become even more beneficial. However, few studies have provided direct evidence of this mechanism. Here, we use data from 180 permanent sample plots in Manitoba, Canada, with a full spatial mapping of all stems, to show that complementarity effects on average increased with neighbourhood competition intensity and temporally rising CO2 , warming and water availability. Importantly, complementarity effects increased with both shade tolerance and phylogenetic dissimilarity between the focal tree and its neighbours. Our results provide further evidence that increasing stand functional and phylogenetic diversity can improve individual tree productivity, especially for individuals experiencing intense competition and may offer an avenue to maintain productivity under global environmental change.


Assuntos
Biodiversidade , Taiga , Canadá , Florestas , Filogenia
7.
Ecol Lett ; 23(1): 55-67, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31637822

RESUMO

Human impacts on genetic diversity are poorly understood yet critical to biodiversity conservation. We used 175 247 COI sequences collected between 1980 and 2016 to assess the global effects of land use and human density on the intraspecific genetic diversity of 17 082 species of birds, fishes, insects and mammals. Human impacts on mtDNA diversity were taxon and scale-dependent, and were generally weak or non-significant. Spatial analyses identified weak latitudinal diversity gradients as well as negative effects of human density on insect diversity, and negative effects of intensive land use on fish diversity. The observed effects were predominantly associated with species turnover. Time series analyses found nearly an equal number of positive and negative temporal trends in diversity, resulting in no net monotonic trend in diversity over this time period. Our analyses reveal critical data and theory gaps and call for increased efforts to monitor global genetic diversity.


Assuntos
Biodiversidade , Mamíferos , Animais , Aves , Peixes , Variação Genética , Humanos
8.
Ecol Lett ; 23(1): 193-207, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31692214

RESUMO

The hypothesis that environmental heterogeneity promotes species richness by increasing opportunities for niche partitioning is a fundamental paradigm in ecology. However, recent studies suggest that heterogeneity-diversity relationships (HDR) are more complex than expected from this niche-based perspective, and often show a decrease in richness at high levels of heterogeneity. These findings have motivated ecologists to propose new mechanisms that may explain such deviations. Here we provide an overview of currently recognised mechanisms affecting the shape of HDRs and present a conceptual model that integrates all previously proposed mechanisms within a unified framework. We also translate the proposed framework into an explicit community dynamic model and use the model as a tool for generating testable predictions concerning how landscape properties interact with species traits in determining the shape of HDRs. Our main finding is that, despite the enormous complexity of such interactions, the predicted HDRs are rather simple, ranging from positive to unimodal patterns in a highly consistent and predictable manner.


Assuntos
Biodiversidade , Ecossistema , Ecologia , Modelos Teóricos
9.
Ecol Lett ; 23(1): 160-171, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31698546

RESUMO

Among the local processes that determine species diversity in ecological communities, fluctuation-dependent mechanisms that are mediated by temporal variability in the abundances of species populations have received significant attention. Higher temporal variability in the abundances of species populations can increase the strength of temporal niche partitioning but can also increase the risk of species extinctions, such that the net effect on species coexistence is not clear. We quantified this temporal population variability for tree species in 21 large forest plots and found much greater variability for higher latitude plots with fewer tree species. A fitted mechanistic model showed that among the forest plots, the net effect of temporal population variability on tree species coexistence was usually negative, but sometimes positive or negligible. Therefore, our results suggest that temporal variability in the abundances of species populations has no clear negative or positive contribution to the latitudinal gradient in tree species richness.


Assuntos
Biodiversidade , Árvores , Biota , Características de Residência
10.
J Environ Manage ; 254: 109743, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31706121

RESUMO

The Life-Cycle Assessment (LCA) is a standard approach for evaluating the environmental impacts of products and processes. This paper presents the LCA of Living Wall Systems (LWS), a new technology for greening the building envelope and improve sustainability. Impacts of manufacture, operation, and use of the systems selected, were evaluated through an LCA. LWS are closely related to several environmental benefits, including improved air quality, increased biodiversity, mitigation of heat island effects, and reduced energy consumption due to savings in indoor cooling and heating. Two prototypes have been selected, taking into account the modularity and the use of organic substrate as selection criteria. The systems evaluated were a plastic-based modular system and a felt-based modular system. The inventory data was gathered through the manufacturers. The LCA approach has been used to assess the impact of these solutions by focusing on the construction phase and its contribution to both the energy balance and the entire life cycle of a building. This approach has never been done before for LWS. The study found that out of the two systems through the manufacturing, construction, and maintenance stage of the LCA, the felt-based LWS has an impact on almost 100% of the impact categories analyzed, while plastic-based LWS has the lowest influence on the total environmental impact.


Assuntos
Poluição do Ar , Biodiversidade
11.
Ecol Lett ; 23(1): 16-32, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31724320

RESUMO

Research on the ecological and evolutionary roles of phytochemicals has recently progressed from studying single compounds to examining chemical diversity itself. A key conceptual advance enabling this progression is the use of species diversity metrics for quantifying phytochemical diversity. In this perspective, we extend the theory developed for species diversity to further our understanding of what exactly phytochemical diversity is and how its many dimensions impact ecological and evolutionary processes. First, we discuss the major dimensions of phytochemical diversity - richness, evenness, functional diversity, and alpha, gamma and beta diversity. We describe their potential independent roles in biotic interactions and the practical challenges associated with their analysis. Second, we re-analyse the published and unpublished datasets to reveal that the phytochemical diversity experienced by an organism (or observed by a researcher) depends strongly on the scale of the interaction and the total amount of phytochemicals involved. We argue that we must account for these frames of reference to meaningfully understand diversity. Moving from a general notion of phytochemical diversity as a single measure to a precise definition of its multidimensional and multiscale nature yields overlooked testable predictions that will facilitate novel insights about the evolutionary ecology of plant biotic interactions.


Assuntos
Biodiversidade , Compostos Fitoquímicos , Evolução Biológica , Ecologia
12.
Ambio ; 49(1): 310-323, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30771208

RESUMO

Guidance for large-scale restoration of natural or semi-natural linear vegetation elements that takes into account the need to maintain human livelihoods such as farming is often lacking. Focusing on a Chilean biodiversity hotspot, we assessed the landscape in terms of existing woody vegetation elements and proposed a buffer strip and hedgerow network. We used spatial analysis based on Google Earth imagery and QGIS, field surveys, seven guidelines linked to prioritization criteria and seedling availability in the region's nurseries, and estimated the budget for implementing the proposed network. The target landscapes require restoring 0.89 ha km-2 of woody buffer strips to meet Chilean law; 1.4 ha km-2 of new hedgerows is also proposed. The cost of restoration in this landscape is estimated in ca. USD 6900 per planted ha of buffer strips and hedgerows. Financial incentives, education, and professional training of farmers are identified as key issues to implement the suggested restoration actions.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Agricultura , Biodiversidade , Chile , Florestas , Humanos
13.
Ambio ; 49(1): 245-257, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30852776

RESUMO

The dramatic increase in anthropogenic activity severely threatens the biodiversity and life-support services that underpin human well-being. The broadened focus of protecting ecosystem services (ESs) better aligns the interests of people and biodiversity conservation. In this study, we used species richness as a surrogate for biodiversity and mapped the key ESs in East Africa with the goal to assess the spatial congruence between biodiversity and ESs, and evaluate the representation of current protected areas (PAs) network for biodiversity and ESs. The results showed that PAs well represented for species richness and regulating services but underrepresented for provisioning services. The PAs network occupies 10.96% of East Africa's land surface, and captures 20.62-26.37% of conservation priorities for vertebrate and plant species. It encompasses more than 16.23% of priority areas for three regulating services, but only 6.17% and 5.22% for crop and livestock production, respectively. Strong correlations and high overlaps exist between species richness and regulating services, particularly for carbon storage, water yield and plants. Thus, we believe that actions taken to conserve biodiversity also will protect certain ESs, which in turn will create new incentives and funding sources for the conservation of biodiversity. Overall, our results have wide-ranging policy implications and can be used to optimize conservation strategies for both biodiversity and multiple ESs in East Africa.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , África Oriental , Biodiversidade , Carbono , Humanos
14.
Ambio ; 49(1): 165-172, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31030418

RESUMO

Construction of water diversions is a common response to the increasing demands for freshwater, often resulting in benefits to communities but with the risk of multiple environmental, economic, and social impacts. Water-diversion projects can favor massive introductions and accelerate biotic homogenization. This study provides empirical evidence on the consequences of a proposed law intended to divert water from two large and historically isolated river basins in Brazil: Tocantins to São Francisco. Compositional similarity (CS) and ß-diversity were quantified encompassing aquatic organisms: mollusks, zooplankton, crustaceans, insects, fishes, amphibians, reptiles, mammals, and plants. For CS we (i) considered only native species, and (ii) simulated the introduction of non-natives and assumed the extinction of threatened species due to this water-diversion project. We highlight the environmental risks of such large-scale projects, which are expected to cause impacts on biodiversity linked to bioinvasion and homogenization, and we recommend alternatives in order to solve water-demand conflicts.


Assuntos
Biodiversidade , Água , Animais , Brasil , Peixes , Água Doce , Rios
15.
Ambio ; 49(1): 85-97, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31055795

RESUMO

Retention forestry implies that biological legacies like dead and living trees are deliberately selected and retained beyond harvesting cycles to benefit biodiversity and ecosystem functioning. This model has been applied for several decades in even-aged, clearcutting (CC) systems but less so in uneven-aged, continuous-cover forestry (CCF). We provide an overview of retention in CCF in temperate regions of Europe, currently largely focused on habitat trees and dead wood. The relevance of current meta-analyses and many other studies on retention in CC is limited since they emphasize larger patches in open surroundings. Therefore, we reflect here on the ecological foundations and socio-economic frameworks of retention approaches in CCF, and highlight several areas with development potential for the future. Conclusions from this perspective paper, based on both research and current practice on several continents, although highlighting Europe, are also relevant to other temperate regions of the world using continuous-cover forest management approaches.


Assuntos
Ecossistema , Agricultura Florestal , Biodiversidade , Conservação dos Recursos Naturais , Europa (Continente) , Florestas , Árvores
16.
Ambio ; 49(1): 231-244, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31201614

RESUMO

A variety of rewilding initiatives are being implemented across Europe, generally characterized by a more functionalist approach to nature management compared to the classic compositional approach. To address the increasing need for a framework to support implementation of rewilding in practical management, we present TRAAIL-Trophic Rewilding Advancement in Anthropogenically Impacted Landscapes. TRAAIL has been co-produced with managers and other stakeholders and provides managers with a framework to categorize rewilding initiatives and to link conventional nature management and rewilding by guiding steps towards a higher degree of self-regulation. Applying TRAAIL to data obtained in a Danish survey of rewilding-inspired initiatives we find that out of 44 initiatives there is no "Full rewilding" initiatives, 3 "Near-full rewilding" initiatives, 23 "Partial rewilding" initiatives, 2 "minimal rewilding" initiatives and 16 "Effort-intensive conservation management" initiatives. This study shows how TRAAIL can guide and inform trophic rewilding on a local and national scale.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , Europa (Continente)
17.
Food Microbiol ; 85: 103309, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31500715

RESUMO

The production of Chinese horse bean-chili-paste (CHCP) involves three fermentation phases: chili-to-moromi fermentation (CF) phase, horse bean-to-meju fermentation (HF) phase and moromi-meju mixed fermentation (MF) phase. To understand the microbial dynamics among these three phases and the potential roles of viable microbes for fermentation, microbial community dynamics was investigated by using culture-dependent and culture-independent methods. Furthermore, the capacities of enzyme-producing of the isolates were determined. During the CF phase, reducing sugar content increased from 3.1% to 3.49%, while pH declined from 4.85 to 4.5. The protein content in the HF phase and MF phase reduced sharply from 22.23% to 10.29% and 4.39%-1.19%, respectively. Bacillus sp., Staphylococcus sp., Oceanobacillus sp., Candida sp., Zygosaccharomyces sp. and Aspergillus sp. dominated the CF phase, while Bacillus sp., Candida sp. and Zygosaccharomyces sp. were the dominant microorganisms in both the HF and MF phases. B. amyloliquefaciens, B. methylotrophicus, B. subtilis, B. licheniformis and A. oryzae possessed strong capacities of producing enzymes, i.e. α-amylase, cellulase and xylanase, acid protease and leucine aminopeptidase, and could make a great contribution to CHCP fermentation.


Assuntos
Bactérias/isolamento & purificação , Fermentação , Microbiologia de Alimentos , Microbiota , Soja/microbiologia , Biodiversidade , Capsicum/microbiologia , Células-Tronco , Vicia faba/microbiologia
18.
Sci Total Environ ; 700: 134418, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31629269

RESUMO

Soil pH is an important predictor of bacterial community composition and diversity. Examining the effects of pH on diversity, structure, interaction, and function of rhizosphere bacterial communities in acidic crop soils provide valuable information for knowing potential role of rhizosphere bacteria in crop yield. Here, we collected soils from artificial greenhouses and applied Illumina Miseq sequencing, quantitative PCR techniques, multiple ecological analysis methods, including topological analysis and functional profiling to analyze our data and validate our hypotheses. We found that the soil physicochemical properties, species diversity, and rhizosphere bacterial community composition were significantly affected by the degree of soil acidification (pH < 5.5 and pH > 5.5) but not vegetation type. Additionally, bacterial absolute abundance increased with higher pH. The 18 soil samples were clustered into two distinct groups of pH < 5.5 and pH > 5.5 at the OTU level, and soil pH had more of an effect on bacterial community composition compared to the other physicochemical variables. In addition, rhizosphere bacteria might presented relatively less competition for survival in pH < 5.5 soils, and bacterial community functions, including nutrient (i.e., carbon, nitrogen, phosphorus, and sulphur) cycling-related enzymes and proteins, were downregulated in more acidic soils (pH < 5.5) based on sequence analysis. To our knowledge, this report is the first to show that pH is a key factor affecting the diversity, structure, interaction, and function of rhizosphere bacterial communities in acidic crop soil in artificial greenhouses. Our findings emphasize that community function and structure of rhizosphere bacteria are closely correlated in more acidic soils, and the decreased crop yield may be correlated with attenuation of the function of the rhizosphere bacterial community.


Assuntos
Rizosfera , Microbiologia do Solo , Solo/química , Bactérias , Biodiversidade , Sequenciamento de Nucleotídeos em Larga Escala , Concentração de Íons de Hidrogênio , Microbiota , Nitrogênio , Fósforo
20.
Huan Jing Ke Xue ; 40(7): 3285-3294, 2019 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854730

RESUMO

Human activities and climate change cause the degradation of subalpine lake ecosystems, which induce the shift of microbial community structure. The spatio-temporal dynamics and the diversity maintenance mechanisms of bacterial communities in Gonghai Lake in Ningwu, Shanxi, were investigated by using Q-PCR and DGGE. The results showed that the temperature), pH, dissolved oxygen, electrical conductivity salinity, and ammonium nitrogen (NH4+) contestation were significantly different among the different sampling depths during different months. Bacterial abundance was the highest in August and the lowest in November, and the abundance was higher in the middle water layer (2 m, 4 m, and 6 m depths), but relatively low in the surface layer and bottom layer (0 m and 8 m depths, respectively). The α diversity index of bacterial communities had significant differences among the different months and depths, and showed an initial decreasing trend and then an increasing trend from April to December. A PERMANOVA test showed that the spatial distribution of bacterial communities was significantly different among depths (P<0.001). The results of redundancy analysis and variation partitioning indicated that environmental selection and diffusion limitation had an effect on the maintenance of the diversity patterns of bacterial communities at the different depths of GH. However, the relative effect of environmental factors was stronger, of which the concentration of NO3-, NO2-, and NH4+ were the main influencing factors. In conclusion, the bacterial communities in GH subalpine lake showed clear spatio-temporal distribution patterns, and environmental variables had a significant effect on shaping the community diversity.


Assuntos
Bactérias/classificação , Lagos/microbiologia , Microbiota , Biodiversidade , China , Concentração de Íons de Hidrogênio , Nitrogênio , Oxigênio , Salinidade , Estações do Ano , Análise Espaço-Temporal , Temperatura Ambiente
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