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1.
Proc Natl Acad Sci U S A ; 121(13): e2318475121, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38466879

RESUMO

Deforestation poses a global threat to biodiversity and its capacity to deliver ecosystem services. Yet, the impacts of deforestation on soil biodiversity and its associated ecosystem services remain virtually unknown. We generated a global dataset including 696 paired-site observations to investigate how native forest conversion to other land uses affects soil properties, biodiversity, and functions associated with the delivery of multiple ecosystem services. The conversion of native forests to plantations, grasslands, and croplands resulted in higher bacterial diversity and more homogeneous fungal communities dominated by pathogens and with a lower abundance of symbionts. Such conversions also resulted in significant reductions in carbon storage, nutrient cycling, and soil functional rates related to organic matter decomposition. Responses of the microbial community to deforestation, including bacterial and fungal diversity and fungal guilds, were predominantly regulated by changes in soil pH and total phosphorus. Moreover, we found that soil fungal diversity and functioning in warmer and wetter native forests is especially vulnerable to deforestation. Our work highlights that the loss of native forests to managed ecosystems poses a major global threat to the biodiversity and functioning of soils and their capacity to deliver ecosystem services.


Assuntos
Ecossistema , Microbiota , Solo/química , Conservação dos Recursos Naturais , Biodiversidade , Florestas , Bactérias , Microbiologia do Solo
2.
Glob Chang Biol ; 30(1): e17084, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273567

RESUMO

Excessive fine sediment (particles <2 mm) deposition in freshwater systems is a pervasive stressor worldwide. However, understanding of ecological response to excess fine sediment in river systems at the global scale is limited. Here, we aim to address whether there is a consistent response to increasing levels of deposited fine sediment by freshwater invertebrates across multiple geographic regions (Australia, Brazil, New Zealand and the UK). Results indicate ecological responses are not globally consistent and are instead dependent on both the region and the facet of invertebrate diversity considered, that is, taxonomic or functional trait structure. Invertebrate communities of Australia were most sensitive to deposited fine sediment, with the greatest rate of change in communities occurring when fine sediment cover was low (below 25% of the reach). Communities in the UK displayed a greater tolerance with most compositional change occurring between 30% and 60% cover. In both New Zealand and Brazil, which included the most heavily sedimented sampled streams, the communities were more tolerant or demonstrated ambiguous responses, likely due to historic environmental filtering of invertebrate communities. We conclude that ecological responses to fine sediment are not generalisable globally and are dependent on landscape filters with regional context and historic land management playing important roles.


Assuntos
Sedimentos Geológicos , Invertebrados , Animais , Invertebrados/fisiologia , Água Doce , Rios , Nova Zelândia , Ecossistema , Biodiversidade , Monitoramento Ambiental
3.
Glob Chang Biol ; 30(1): e17057, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273541

RESUMO

The worldwide retreat of glaciers is causing a faster than ever increase in ice-free areas that are leading to the emergence of new ecosystems. Understanding the dynamics of these environments is critical to predicting the consequences of climate change on mountains and at high latitudes. Climatic differences between regions of the world could modulate the emergence of biodiversity and functionality after glacier retreat, yet global tests of this hypothesis are lacking. Nematodes are the most abundant soil animals, with keystone roles in ecosystem functioning, but the lack of global-scale studies limits our understanding of how the taxonomic and functional diversity of nematodes changes during the colonization of proglacial landscapes. We used environmental DNA metabarcoding to characterize nematode communities of 48 glacier forelands from five continents. We assessed how different facets of biodiversity change with the age of deglaciated terrains and tested the hypothesis that colonization patterns are different across forelands with different climatic conditions. Nematodes colonized ice-free areas almost immediately. Both taxonomic and functional richness quickly increased over time, but the increase in nematode diversity was modulated by climate, so that colonization started earlier in forelands with mild summer temperatures. Colder forelands initially hosted poor communities, but the colonization rate then accelerated, eventually leveling biodiversity differences between climatic regimes in the long term. Immediately after glacier retreat, communities were dominated by colonizer taxa with short generation time and r-ecological strategy but community composition shifted through time, with increased frequency of more persister taxa with K-ecological strategy. These changes mostly occurred through the addition of new traits instead of their replacement during succession. The effects of local climate on nematode colonization led to heterogeneous but predictable patterns around the world that likely affect soil communities and overall ecosystem development.


Assuntos
Ecossistema , Nematoides , Animais , Solo , Camada de Gelo , Biodiversidade
4.
Foodborne Pathog Dis ; 21(10): 653-661, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39052696

RESUMO

Staphylococcus aureus (S. aureus) is a pathogen capable of causing severe diseases and exhibiting resistance to multiple antibiotics. However, there is a significant lack of comprehensive research on the global prevalence of its antibiotic resistance genes (ARGs). This study provided a comprehensive analysis of ARGs in S. aureus, using 113,842 S. aureus genome sequences from the National Center for Biotechnology Information database. The results revealed that a significant majority (84%) of these genomes harbored at least one ARG, with a total of 389,464 ARG sequences identified across 19 major types and 103 subtypes. These ARGs exhibited varied abundances and diversities, linked primarily to clinical cases worldwide. ARGs for fluoroquinolones, multidrug resistance, bacitracin, tetracyclines, beta-lactams, and aminoglycosides were notably abundant, ranging from 3.16 × 10-5 to 1.49 copies of ARG per million bp. Variations in the abundance and diversity of ARGs were observed between countries, with middle- and low-income countries showing higher gene abundance but lower diversity compared with high-income countries. Temporal analysis over 30 years showed a fluctuating decline in ARG abundance alongside an increase in diversity, suggesting evolving resistance mechanisms. The study also explored the role of mobile genetic elements in ARG dissemination, finding a substantial proportion of ARG subtypes associated with plasmids and insertion sequence elements, indicating their potential for spread across borders. The global distribution of mobile ARGs was further analyzed, revealing the extensive reach of certain ARGs across countries. This research provides valuable insights into the prevalence and dissemination of antibiotic resistance in S. aureus on a global scale, aiding in the development of effective monitoring and control strategies to combat ARGs in S. aureus and other pathogens.


Assuntos
Antibacterianos , Genoma Bacteriano , Infecções Estafilocócicas , Staphylococcus aureus , Staphylococcus aureus/genética , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/epidemiologia , Humanos , Genômica , Farmacorresistência Bacteriana Múltipla/genética , Farmacorresistência Bacteriana/genética , Genes Bacterianos
5.
Environ Geochem Health ; 46(5): 165, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592368

RESUMO

Soil pollution around Pb-Zn smelters has attracted widespread attention around the world. In this study, we compiled a database of eight potentially toxic elements (PTEs) Pb, Zn, Cd, As, Cr, Ni, Cu, and Mn in the soil of Pb-Zn smelting areas by screening the published research papers from 2000 to 2023. The pollution assessment and risk screening of eight PTEs were carried out by geo-accumulation index (Igeo), potential ecological risk index (PERI) and health risk assessment model, and Monte Carlo simulation employed to further evaluate the probabilistic health risks. The results suggested that the mean values of the eight PTEs all exceeded the corresponding values in the upper crust, and more than 60% of the study sites had serious Pb and Cd pollution (Igeo > 4), with Brazil, Belgium, China, France and Slovenia having higher levels of pollution than other regions. Besides, PTEs in smelting area caused serious ecological risk (PERI = 10912.12), in which Cd was the main contributor to PREI (86.02%). The average hazard index (HI) of the eight PTEs for adults and children was 7.19 and 9.73, respectively, and the average value of total carcinogenic risk (TCR) was 4.20 × 10-3 and 8.05 × 10-4, respectively. Pb and As are the main contributors to non-carcinogenic risk, while Cu and As are the main contributors to carcinogenic risk. The probability of non-carcinogenic risk in adults and children was 84.05% and 97.57%, while carcinogenic risk was 92.56% and 79.73%, respectively. In summary, there are high ecological and health risks of PTEs in the soil of Pb-Zn smelting areas, and Pb, Cd, As and Cu are the key elements that cause contamination and risk, which need to be paid attention to and controlled. This study is expected to provide guidance for soil remediation in Pb-Zn smelting areas.


Assuntos
Cádmio , Chumbo , Adulto , Criança , Humanos , Chumbo/toxicidade , Carcinogênese , Carcinógenos , Poluição Ambiental , Probabilidade , Medição de Risco , Solo , Zinco
6.
Ann Bot ; 131(5): 737-750, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36273331

RESUMO

BACKGROUND AND AIMS: The hart's tongue fern (HTF) complex is a monophyletic group composed of five geographically segregated members with divergent abundance patterns across its broad geographic range. We postulated hierarchical systems of environmental controls in which climatic and land-use change drive abundance patterns at the global scale, while various ecological conditions function as finer scale determinants that further increase geographic disparities at regional to local scales. METHODS: After quantifying the abundance patterns of the HTF complex, we estimated their correlations with global climate and land-use dynamics. Regional determinants were assessed using boosted regression tree models with 18 potential ecological variables. Moreover, we investigated long-term population trends in the USA to understand the interplay of climate change and anthropogenic activities on a temporal scale. KEY RESULTS: Latitudinal climate shifts drove latitudinal abundance gradients, and regionally different levels of land-use change resulted in global geographic disparities in population abundance. At a regional scale, population isolation, which accounts for rescue effects, played an important role, particularly in Europe and East Asia where several hot spots occurred. Furthermore, the variables most strongly influencing abundance patterns greatly differed by region: precipitation seasonality in Europe; spatial heterogeneity of temperature and precipitation in East Asia; and magnitudes of past climate change, temperature seasonality and edaphic conditions in North America. In the USA, protected populations showed increasing trends compared with unprotected populations at the same latitude, highlighting the critical role of habitat protection in conservation measures. CONCLUSIONS: Geographic disparities in the abundance patterns of the HTF complex were determined by hierarchical systems of environmental controls, wherein climatic and land-use dynamics act globally but are modulated by various regional and local determinants operating at increasingly finer scales. We highlighted that fern conservation must be tailored to particular geographic contexts and environmental conditions by incorporating a better understanding of the dynamics acting at different spatiotemporal scales.


Assuntos
Gleiquênias , Ecossistema , Mudança Climática , Temperatura , Ásia Oriental
7.
Naturwissenschaften ; 110(6): 54, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37957333

RESUMO

The current ecological crisis has risen extinction rates to similar levels of ancient mass extinctions. However, it seems to not be acting uniformly across all species but affecting species differentially. This suggests that species' susceptibility to the extinction process is mediated by specific traits. Since understanding this response mechanism at large scales will benefit conservation effort around the world, we used the IUCN global threat status and population trends of 8281 extant bird species as proxies of the extinction risk to identify the species-specific traits affecting their susceptibility to extinction within the biogeographic regions and at the global scale. Using linear mixed effect models and multinomial models, we related the global threat status and the population trends with the following traits: migratory strategy, habitat and diet specialization, body size, and generation length. According to our results and independently of the proxy used, more vulnerable species are sedentary and have larger body size, longer generation time, and higher degree of habitat specialization. These relationships apply globally and show little variation across biogeographic regions. We suggest that such concordant patterns might be caused either by a widespread occurrence of the same threats such as habitat modification or by a uniform capacity of some traits to reflect the impact of different local threats. Regardless of the cause of this pattern, our study identified the traits that affect species' response capability to the current ecological crisis. Conservation effort should focus on the species with trait values indicating the limited response capacity to overcome this crisis.


Assuntos
Mudança Climática , Extinção Biológica , Animais , Ecossistema , Especificidade da Espécie , Aves , Conservação dos Recursos Naturais , Biodiversidade
8.
Proc Natl Acad Sci U S A ; 117(52): 33017-33027, 2020 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-33318212

RESUMO

Knowledge of spatiotemporal distribution and likelihood of (re)occurrence of salt-affected soils is crucial to our understanding of land degradation and for planning effective remediation strategies in face of future climatic uncertainties. However, conventional methods used for tracking the variability of soil salinity/sodicity are extensively localized, making predictions on a global scale difficult. Here, we employ machine-learning techniques and a comprehensive set of climatic, topographic, soil, and remote sensing data to develop models capable of making predictions of soil salinity (expressed as electrical conductivity of saturated soil extract) and sodicity (measured as soil exchangeable sodium percentage) at different longitudes, latitudes, soil depths, and time periods. Using these predictive models, we provide a global-scale quantitative and gridded dataset characterizing different spatiotemporal facets of soil salinity and sodicity variability over the past four decades at a ∼1-km resolution. Analysis of this dataset reveals that a soil area of 11.73 Mkm2 located in nonfrigid zones has been salt-affected with a frequency of reoccurrence in at least three-fourths of the years between 1980 and 2018, with 0.16 Mkm2 of this area being croplands. Although the net changes in soil salinity/sodicity and the total area of salt-affected soils have been geographically highly variable, the continents with the highest salt-affected areas are Asia (particularly China, Kazakhstan, and Iran), Africa, and Australia. The proposed method can also be applied for quantifying the spatiotemporal variability of other dynamic soil properties, such as soil nutrients, organic carbon content, and pH.

9.
Environ Monit Assess ; 195(7): 885, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37358677

RESUMO

Residential buildings generate significant greenhouse gas (GHG) emissions and consume energy throughout their life cycle. In recent years, research on GHG emissions and energy consumption of buildings has developed rapidly in response to the growing climate change and energy crisis. Life cycle assessment (LCA) is an important method for evaluating the environmental impacts of the building sector. However, LCA studies of buildings show widely varying outcomes across the world. Besides, environmental impact assessment from a whole life cycle perspective has been undeveloped and slow. Our work presents a systematic review and meta-analysis of LCA studies on GHG emissions and energy consumption in the preuse, use, and demolition stages of residential buildings. We aim to examine the differences among the results of diverse case studies and demonstrate the spectrum of variations under contextual disparities. Results show that residential building emits about 2928 kg GHG emission and consumes about 7430 kWh of energy per m2 of gross building area on average throughout the life cycle. Residential buildings have an average GHG emission of 84.81% in the use phase, followed by the preuse phase and demolition phase; the mean energy consumption in the use stage occupied the largest share of 84.52%, followed by preuse stage and demolition stage. GHG emissions and energy use vary significantly in different regions due to different building types, natural conditions, and lifestyles. Our study stresses the compelling requirement to slash GHG emissions and optimize energy consumption from residential buildings by use of low carbon building materials, energy structure adjustment, consumer behavior transformation, etc.


Assuntos
Gases de Efeito Estufa , Monitoramento Ambiental , Materiais de Construção , Carbono , Mudança Climática , Efeito Estufa
10.
J Anim Ecol ; 91(9): 1770-1780, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35579946

RESUMO

Anthropogenic land use is threatening global biodiversity. As one of the most abundant animals on Earth, nematodes occupy several key positions in belowground food webs and contribute to many ecosystem functions and services. However, the effects of land use on nematode abundance and its determinants remain poorly understood at a global scale. To characterize nematodes' responses to land use across trophic groups, we used a dataset of 6,825 soil samples globally to assess how nematode abundance varies among regional land-use types (i.e. primary vegetation, secondary vegetation, pasture, cropland and urban) and local land-use intensities (i.e. human-managed or not). We also quantified the interactive effects of land use and environmental predictors (i.e. mean annual temperature, annual precipitation, soil organic carbon, soil pH, global vegetation biomass and global vegetation productivity) on nematode abundance. We found that total nematode abundance and the abundance of bacterivores, fungivores, herbivores, omnivores and predators generally increased or were not affected under management across land-use types. Specifically, the most numerically abundant bacterivores were higher in managed than in unmanaged secondary vegetation habitats and urban areas, and herbivores were more abundant in managed than in unmanaged primary and secondary vegetation habitats. Furthermore, the numbers of significant environmental predictors of nematode abundance were reduced and the magnitude and the direction of the predictors were changed under management. We also found that nematode abundance was more variable and less determined by environmental factors in urban than in other land-use types. These findings challenge the view that human land use decreases animal abundance across trophic groups, but highlight that land use is altering the trophic composition of soil nematodes and its relationships with the environment at the global scale.


Assuntos
Nematoides , Solo , Animais , Biodiversidade , Carbono , Ecossistema , Humanos , Nematoides/fisiologia , Solo/química
11.
Proc Natl Acad Sci U S A ; 116(27): 13434-13439, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31209040

RESUMO

Identifying the drivers and processes that determine globally the geographic range size of species is crucial to understanding the geographic distribution of biodiversity and further predicting the response of species to current global changes. However, these drivers and processes are still poorly understood, and no ecological explanation has emerged yet as preponderant in explaining the extent of species' geographical range. Here, we identify the main drivers of the geographic range size variation in freshwater fishes at global and biogeographic scales and determine how these drivers affect range size both directly and indirectly. We tested the main hypotheses already proposed to explain range size variation, using geographic ranges of 8,147 strictly freshwater fish species (i.e., 63% of all known species). We found that, contrary to terrestrial organisms, for which climate and topography seem preponderant in determining species' range size, the geographic range sizes of freshwater fishes are mostly explained by the species' position within the river network, and by the historical connection among river basins during Quaternary low-sea-level periods. Large-ranged fish species inhabit preferentially lowland areas of river basins, where hydrological connectivity is the highest, and also are found in river basins that were historically connected. The disproportionately high explanatory power of these two drivers suggests that connectivity is the key component of riverine fish geographic range sizes, independent of any other potential driver, and indicates that the accelerated rates in river fragmentation might strongly affect fish species distribution and freshwater biodiversity.


Assuntos
Peixes , Animais , Biodiversidade , Demografia , Ecossistema , Água Doce , Geografia , Hidrologia , Rios
12.
Proc Natl Acad Sci U S A ; 116(14): 6891-6896, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30877251

RESUMO

Belowground organisms play critical roles in maintaining multiple ecosystem processes, including plant productivity, decomposition, and nutrient cycling. Despite their importance, however, we have a limited understanding of how and why belowground biodiversity (bacteria, fungi, protists, and invertebrates) may change as soils develop over centuries to millennia (pedogenesis). Moreover, it is unclear whether belowground biodiversity changes during pedogenesis are similar to the patterns observed for aboveground plant diversity. Here we evaluated the roles of resource availability, nutrient stoichiometry, and soil abiotic factors in driving belowground biodiversity across 16 soil chronosequences (from centuries to millennia) spanning a wide range of globally distributed ecosystem types. Changes in belowground biodiversity during pedogenesis followed two main patterns. In lower-productivity ecosystems (i.e., drier and colder), increases in belowground biodiversity tracked increases in plant cover. In more productive ecosystems (i.e., wetter and warmer), increased acidification during pedogenesis was associated with declines in belowground biodiversity. Changes in the diversity of bacteria, fungi, protists, and invertebrates with pedogenesis were strongly and positively correlated worldwide, highlighting that belowground biodiversity shares similar ecological drivers as soils and ecosystems develop. In general, temporal changes in aboveground plant diversity and belowground biodiversity were not correlated, challenging the common perception that belowground biodiversity should follow similar patterns to those of plant diversity during ecosystem development. Taken together, our findings provide evidence that ecological patterns in belowground biodiversity are predictable across major globally distributed ecosystem types and suggest that shifts in plant cover and soil acidification during ecosystem development are associated with changes in belowground biodiversity over centuries to millennia.


Assuntos
Biodiversidade , Modelos Biológicos
13.
Glob Chang Biol ; 26(9): 4952-4965, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32564461

RESUMO

The growing human enterprise has sparked greater interest in identifying ecological thresholds in land use conversion beyond which populations or communities demonstrate abrupt nonlinear or substantive change in species composition. Such knowledge remains fundamental to understanding ecosystem resilience to environmental degradation and informing land use planning into the future. Confronting this challenge has been largely limited to inferring thresholds in univariate metrics of species richness and indices of biotic integrity and has largely ignored how land use legacies of the past may shape community responses of today. By leveraging data for 13,069 riverine sites from temperate, subtropical, and boreal climate zones on four continents, we characterize patterns of community change along diverse gradients of urbanization and agricultural land use, and identity threshold values beyond which significant alterations in species composition exists. Our results demonstrate the apparent universality by which freshwater fish communities are sensitive to even low levels of watershed urbanization (range of threshold values: 1%-12%), but consistently higher (and more variable) levels of agricultural development (2%-37%). We demonstrated that fish community compositional thresholds occurred, in general, at lower levels of watershed urbanization and agriculture when compared to threshold responses in species richness. This supports the notion that aggregated taxon-specific responses may better reflect the complexity of assemblage responses to land use development. We further revealed that the ghost of land use past plays an important role in moderating how current-day fish communities respond to land use intensification. Subbasins of the United States experiencing greater rates of past land use change demonstrated higher current-day thresholds. Threshold responses of community composition, such as those identified in our study, illustrate the need for globally coordinated efforts to prioritize country-specific management and policy initiatives that ensure that freshwater fish diversity is not inevitably lost in the future.


Assuntos
Biodiversidade , Ecossistema , Agricultura , Animais , Peixes , Humanos , Urbanização
14.
Biol Res ; 53(1): 29, 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32631429

RESUMO

Arid environments are defined by the lack of water availability, which is directly related to the mean annual precipitation (MAP), and high values of solar irradiation, which impacts the community composition of animals, plants, and the microbial structure of the soil. Recent advances in NGS technologies have expanded our ability to characterize microbiomes, allowing environmental microbiologists to explore the complete microbial structure. Intending to identify and describe the state-of-the-art of bacterial communities in arid soils at a global scale, and to address the effect that some environmental features may have on them, we performed a systematic review based on the PRISMA guideline. Using a combination of keywords, we identified a collection of 66 studies, including 327 sampled sites, reporting the arid soil bacterial community composition by 16S rDNA gene high-throughput sequencing. To identify factors that can modulate bacterial communities, we extracted the geographical, environmental, and physicochemical data. The results indicate that even though each sampled site was catalogued as arid, they show wide variability in altitude, mean annual temperature (MAT), soil pH and electric conductivity, within and between arid environments. We show that arid soils display a higher abundance of Actinobacteria and lower abundance of Proteobacteria, Cyanobacteria, and Planctomycetes, compared with non-arid soil microbiomes, revealing that microbial structure seems to be strongly modulated by MAP and MAT and not by pH in arid soils. We observed that environmental and physicochemical features were scarcely described among studies, hence, we propose a reporting guideline for further analysis, which will allow deepening the knowledge of the relationship between the microbiome and abiotic factors in arid soil. Finally, to understand the academic collaborations landscape, we developed an analysis of the author's network, corroborating a low degree of connectivity and collaborations in this research topic. Considering that it is crucial to understand how microbial processes develop and change in arid soils, our analysis emphasizes the need to increase collaborations between research groups worldwide.


Assuntos
Microbiota , Microbiologia do Solo , Animais , Microbiota/genética , Plantas , Proteobactérias , Solo
15.
Parasitology ; 146(2): 168-175, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30012225

RESUMO

We need reliable data on the spatial distribution of parasites in order to achieve an inventory of global parasite biodiversity and establish robust conservation initiatives based on regional disease risk. This requires an integrated and spatially consistent effort toward the discovery of new parasite species. Using a large and representative dataset on the geographical coordinates where 4943 helminth species were first discovered, we first test whether the geographical distribution of parasite species reports is spatially congruent across helminth higher taxa; i.e. whether areas, where many trematodes are found, are also areas where many nematodes or cestodes have been discovered. Second, we test whether the global geographical distribution of new helminth species reports has changed significantly over time, i.e. across the last few decades. After accounting for spatial autocorrelation in the data, we find no strong statistical support for either of the patterns we investigated. Overall, our results indicate that helminth species discoveries are both spatially incongruent among higher taxa of helminths, and inconsistent over time. These findings suggest that the global parasite discovery effort is inefficient, spatially biased and subject to idiosyncrasies. Coordinated biodiscovery programmes, involving research teams with expertise in multiple taxonomic groups, seem the best approach to remedy these issues.


Assuntos
Helmintíase Animal/parasitologia , Helmintos/classificação , Vertebrados/parasitologia , Animais , Geografia , Análise Espacial , Fatores de Tempo
16.
Glob Chang Biol ; 24(10): 4614-4625, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29851235

RESUMO

The relationship between levels of dominance and species richness is highly contentious, especially in ant communities. The dominance-impoverishment rule states that high levels of dominance only occur in species-poor communities, but there appear to be many cases of high levels of dominance in highly diverse communities. The extent to which dominant species limit local richness through competitive exclusion remains unclear, but such exclusion appears more apparent for non-native rather than native dominant species. Here we perform the first global analysis of the relationship between behavioral dominance and species richness. We used data from 1,293 local assemblages of ground-dwelling ants distributed across five continents to document the generality of the dominance-impoverishment rule, and to identify the biotic and abiotic conditions under which it does and does not apply. We found that the behavioral dominance-diversity relationship varies greatly, and depends on whether dominant species are native or non-native, whether dominance is considered as occurrence or relative abundance, and on variation in mean annual temperature. There were declines in diversity with increasing dominance in invaded communities, but diversity increased with increasing dominance in native communities. These patterns occur along the global temperature gradient. However, positive and negative relationships are strongest in the hottest sites. We also found that climate regulates the degree of behavioral dominance, but differently from how it shapes species richness. Our findings imply that, despite strong competitive interactions among ants, competitive exclusion is not a major driver of local richness in native ant communities. Although the dominance-impoverishment rule applies to invaded communities, we propose an alternative dominance-diversification rule for native communities.


Assuntos
Formigas/fisiologia , Biodiversidade , Animais , Clima , Ecossistema
17.
Environ Monit Assess ; 190(12): 739, 2018 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-30460409

RESUMO

Tree invasion has the potential to negatively affect biodiversity and ecosystems, with invasive alien trees (IATs) expanding widely in protected areas (PAs) across different habitats. Thus, the effectiveness of PAs might be reduced. Investigation of the distributions of IAT is urgently required to improve the effective conservation management of PAs. We projected the potential distributions of 10 IATs, which included Acacia mearnsii, Ardisia elliptica, Cecropia peltata, Cinchona pubescens, Leucaena leucocephala, Melaleuca quinquenervia, Miconia calvescens, Morella faya, Prosopis glandulosa, and Spathodea campanulata, that have a serious influence on global biodiversity and assessed the distribution possibilities of these IATs in PAs based on the PA categories of the International Union for Conservation of Nature (IUCN). The overall potential distributions of these 10 IATs included Latin America, central and southern Africa, southeastern Asia, eastern Australia and New Zealand, and western Europe. Annual mean temperature, temperature seasonality, annual precipitation, and soil bulk density were found to be important environmental variables for the potential distributions of these IATs. Overall, A. mearnsii, A. elliptica, C. peltata, L. leucocephala, M. quinquenervia, M. calvescens, and S. campanulata were distributed mainly in the IUCN PA categories of national parks and PAs with sustainable use of natural resources. We proposed the following for conservation management of PAs: (1) completion of species inventories for PAs, (2) better understanding of factors driving invasions in PAs, (3) assessment of the efficiency of management within particular PAs, and (4) evaluation of changes in trends regarding plant invasions in PAs under climate change conditions.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental/métodos , Espécies Introduzidas , Árvores/classificação , África , Sudeste Asiático , Austrália , Biodiversidade , Ecossistema , Europa (Continente) , América Latina , Nova Zelândia , Tempo (Meteorologia)
18.
Glob Chang Biol ; 23(8): 3418-3432, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28067005

RESUMO

Phosphorus (P) availability in soils limits crop yields in many regions of the World, while excess of soil P triggers aquatic eutrophication in other regions. Numerous processes drive the global spatial distribution of P in agricultural soils, but their relative roles remain unclear. Here, we combined several global data sets describing these drivers with a soil P dynamics model to simulate the distribution of P in agricultural soils and to assess the contributions of the different drivers at the global scale. We analysed both the labile inorganic P (PILAB ), a proxy of the pool involved in plant nutrition and the total soil P (PTOT ). We found that the soil biogeochemical background corresponding to P inherited from natural soils at the conversion to agriculture (BIOG) and farming practices (FARM) were the main drivers of the spatial variability in cropland soil P content but that their contribution varied between PTOT vs. PILAB . When the spatial variability was computed between grid cells at half-degree resolution, we found that almost all of the PTOT spatial variability could be explained by BIOG, while BIOG and FARM explained 38% and 63% of PILAB spatial variability, respectively. Our work also showed that the driver contribution was sensitive to the spatial scale characterizing the variability (grid cell vs. continent) and to the region of interest (global vs. tropics for instance). In particular, the heterogeneity of farming practices between continents was large enough to make FARM contribute to the variability in PTOT at that scale. We thus demonstrated how the different drivers were combined to explain the global distribution of agricultural soil P. Our study is also a promising approach to investigate the potential effect of P as a limiting factor for agroecosystems at the global scale.


Assuntos
Agricultura , Fósforo/química , Solo/química , Produtos Agrícolas , Plantas
19.
Proc Natl Acad Sci U S A ; 111(44): 15659-64, 2014 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-25331867

RESUMO

El Niño Southern Oscillation (ENSO) is the most dominant interannual signal of climate variability and has a strong influence on climate over large parts of the world. In turn, it strongly influences many natural hazards (such as hurricanes and droughts) and their resulting socioeconomic impacts, including economic damage and loss of life. However, although ENSO is known to influence hydrology in many regions of the world, little is known about its influence on the socioeconomic impacts of floods (i.e., flood risk). To address this, we developed a modeling framework to assess ENSO's influence on flood risk at the global scale, expressed in terms of affected population and gross domestic product and economic damages. We show that ENSO exerts strong and widespread influences on both flood hazard and risk. Reliable anomalies of flood risk exist during El Niño or La Niña years, or both, in basins spanning almost half (44%) of Earth's land surface. Our results show that climate variability, especially from ENSO, should be incorporated into disaster-risk analyses and policies. Because ENSO has some predictive skill with lead times of several seasons, the findings suggest the possibility to develop probabilistic flood-risk projections, which could be used for improved disaster planning. The findings are also relevant in the context of climate change. If the frequency and/or magnitude of ENSO events were to change in the future, this finding could imply changes in flood-risk variations across almost half of the world's terrestrial regions.


Assuntos
Benzocaína , El Niño Oscilação Sul , Inundações , Modelos Teóricos
20.
Ecol Econ ; 137: 184-194, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28674462

RESUMO

This study presents the first meta-analysis on the economic value of ecosystem services delivered by lakes. A worldwide data set of 699 observations drawn from 133 studies combines information reported in primary studies with geospatial data. The meta-analysis explores antagonisms and synergies between ecosystem services. This is the first meta-analysis to incorporate simultaneously external geospatial data and ecosystem service interactions. We first show that it is possible to reliably predict the value of ecosystem services provided by lakes based on their physical and geographic characteristics. Second, we demonstrate that interactions between ecosystem services appear to be significant for explaining lake ecosystem service values. Third, we provide an estimation of the average value of ecosystem services provided by lakes: between 106 and 140 USD$2010 per respondent per year for non-hedonic price studies and between 169 and 403 USD$2010 per property per year for hedonic price studies.

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