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1.
Recurso Educacional Abierto en Portugués | CVSP - Brasil | ID: cfc-393798

RESUMEN

Vídeoaula sobre "modelos de desenvolvimento que respeitem e promovam a diversidade sociocultural dos povos indígenas", por Ana Lúcia Pontes, pesquisadora da ENSP e coordenadora do Grupo Temático de Saúde Indígena da ABRASCO, durante o evento: Colóquios da Semana Nacional de Ciência e Tecnologia 2019, tem como tema "Bioeconomia: Diversidade e Riqueza para o Desenvolvimento Sustentável". Data: 16 Outubro de 2019


Asunto(s)
Indicadores de Desarrollo Sostenible , Biodiversidad , Derechos de los Pueblos Indígenas
2.
J Environ Manage ; 255: 109831, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-32063316

RESUMEN

Zostera capensis is a keystone species providing essential ecosystem services to southern African coastal systems. Like most seagrasses globally, Z. capensis is declining and under threat from anthropogenic pressures, and indicators of seagrass health and resilience may be of interest in preventing further declines. As intraspecific diversity is an important component of resilience, we used a pooled RADseq approach to generate genome-wide measures of variation across the entire South African distribution of Z. capensis. Using nucleotide diversity, heterozygosity and allelic richness we tested for associations with fine-scale anthropogenic pressure data compiled by the South African National Biodiversity Assessment using generalised linear models. Increased fishing effort, habitat loss, sand mining and a change in estuary flow dynamics were found to play an important role in decreasing nucleotide diversity and expected heterozygosity, most likely due to the loss of less resilient genotypes as a result of direct physical damage or indirect consequences. As the building block for adaptation, nucleotide diversity is particularly important for resilience. Because of this, as well as the fact that nucleotide diversity displayed the most distinct difference between the west and east coast, and responded most strongly to anthropogenic pressures, we suggest that this may be a useful measure for monitoring genetic or genomic variation. As genomic diversity influences resilience and resistance to disturbances, the remaining diversity in South African seagrass beds urgently needs to be conserved through restoration efforts and careful management of pressures.


Asunto(s)
Zosteraceae , Biodiversidad , Ecosistema , Estuarios , Genómica
3.
BMC Ecol ; 20(1): 9, 2020 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-32039727

RESUMEN

BACKGROUND: Occurrences in land use, human activities and climate change have both direct and indirect influences on the environment. Of interest for this study is mining; a common activity in developing countries such as Nigeria which is endowed with over 34 solid minerals. The gold mining sites in the Southwest region of the country is predominantly by Artisanal and Small-Scale Mining (ASM). Though the benefits are known, its induced consequences are enormous. To understand its extent of floristic diversity, identification of functional plants and plant species surviving on the mined sites (despite its characterized mining and alteration level); this study compared the floristic composition of an abandoned mining site (Site 1), an active mining site (Site 2) and an undisturbed vegetation sites (Control) of similar vegetation zone. RESULTS: A total of 54, 28 and 37 species belonging to 31, 20 and 23 families were found on Site 1, Site 2 and the control site, respectively. It shows that the floristic composition of all the sites has been altered due to its past intense agricultural colonization and human activities, but severe on Site 1 and 2 due to mining. Lots of the identified species are functional species and stand as ecological indicators. Species such as Acanthus montanus and Icacina trichantha found on the Control sites are native and significance but species such as Capsicum frutescens and Crassocephalum crepidioides on Site 2 are due to human inference while most species on Site 1 shows both original and altered floristic composition (e.g. Adenia venenata and Grewia flavescens). CONCLUSIONS: Apart from the on-going farming activities, ASM activities such as pollution, deforestation and exposure of the forest soils to direct sunlight has greatly stressed and disturbed the floristic composition, species richness, life form patterns, of the mined sites as well as introduction of non-native plant species. It is therefore necessary to develop effective approaches and policies to curb these illegal ASM activities, empower the community (especially youths), stabilize the economy and establish sustainable development strategies with adequate reclamation measures.


Asunto(s)
Biodiversidad , Oro , Adolescente , Humanos , Minería , Nigeria , Plantas
4.
Microbes Environ ; 35(1)2020.
Artículo en Inglés | MEDLINE | ID: mdl-31932539

RESUMEN

Diverse members of Bradyrhizobium diazoefficiens, B. japonicum, and B. ottawaense were isolated from the roots of field-grown sorghum plants in Fukushima, and classified into "Rhizobia" with nodulated soybeans, "Free-living diazotrophs", and "Non-diazotrophs" by nitrogen fixation and nodulation assays. Genome analyses revealed that B. ottawaense members possessed genes for N2O reduction, but lacked those for the Type VI secretion system (T6SS). T6SS is a new bacterial weapon against microbial competitors. Since T6SS-possessing B. diazoefficiens and B. japonicum have mainly been isolated from soybean nodules in Japan, T6SS-lacking B. ottawaense members may be a cryptic lineage of soybean bradyrhizobia in Japan.


Asunto(s)
Biodiversidad , Bradyrhizobium/genética , Oxidorreductasas/genética , Sorghum/microbiología , Sistemas de Secreción Tipo VI/deficiencia , Bradyrhizobium/clasificación , Bradyrhizobium/aislamiento & purificación , Variación Genética , Fijación del Nitrógeno/genética , Filogenia , Nodulación de la Raíz de la Planta/genética , Raíces de Plantas/microbiología , Rhizobium/clasificación , Rhizobium/genética , Rhizobium/aislamiento & purificación , Sistemas de Secreción Tipo VI/genética
5.
Water Res ; 171: 115468, 2020 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-31926373

RESUMEN

Anaerobic ammonium oxidizing (anammox) bacteria can directly convert ammonium and nitrite to nitrogen gas anaerobically and were responsible for a substantial part of the fixed nitrogen loss and re-oxidation of nitrite to nitrate in freshwater and marine ecosystems. Although a wide variety of studies have been undertaken to investigate the abundance and biodiversity of anammox bacteria so far, ecological niche differentiation of anammox bacteria is still not fully understood. To assess their growth behavior and consequent population dynamics at a given environment, the Monod model is often used. Here, we summarize the Monod kinetic parameters such as the maximum specific growth rate (µmax) and the half-saturation constant for nitrite (KNO2-) and ammonium (KNH4+) of five known candidatus genera of anammox bacteria. We also discuss potential pivotal environmental factors and metabolic flexibility that influence the community compositions of anammox bacteria. Particularly biodiversity of the genus "Scalindua" might have been largely underestimated. Several anammox bacteria have been successfully enriched from various source of biomass. We reevaluate their enrichment methods and culture medium compositions to gain a clue of niche differentiation of anammox bacteria. Furthermore, we formulate the current issues that must be addressed. Overall this review re-emphasizes the importance of enrichment cultures (preferably pure cultures), physiological characterization and direct microbial competition studies using enrichment cultures in laboratories.


Asunto(s)
Compuestos de Amonio , Ecosistema , Anaerobiosis , Bacterias , Bacterias Anaerobias , Biodiversidad , Nitritos , Oxidación-Reducción , Compuestos de Amonio Cuaternario , ARN Ribosómico 16S
6.
Science ; 367(6475): 249, 2020 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-31949068
8.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(1): 60-66, 2020 Jan.
Artículo en Chino | MEDLINE | ID: mdl-31950791

RESUMEN

Objective: To optimize the preparation parameters of the new silk birth-canal microecology transporter (BMT) for transferring the symbiotic bacteria of the birth canal efficiently. Methods: Birth canal microbial samples of 30 full term pregnant women at admission were collected as the control group (NC, n=30). The experimental group included 18 pregnant women terminated by Cesarean section, who were divided into 6 sub-groups (M1-M6, n=3) to complete the transfer tests of the birth-canal microecology. The new silk BMT was processed in the sterile liquid of the different osmotic pressure with the different immersion depth, and was placed in the vagina of the pregnant women for 1 h before sealed. All extracted DNA specimens were amplified in the V3-V4 region of the 16S rDNA, and were sequenced by Illumina Hiseq2500. Microbial diversity analysis was performed by Mothur, QIIME, Lefse and Metastat. Welch's t-test and Anosim nonparametric test were used to compare the difference between groups. Results: The new silk BMT with 70% immersion depth could be fully covered by the solution, and had good solution preserving and adhesion. The subjects had no foreign body sensation with satisfied experience. Both of the microbes on the new BMT and the control group were lactobacillus as the dominant bacteria genus. The microbial diversity and bacteria constitution in the new BMT was similar to the control group in the condition of 0.45% NaCl solution and 70% immersion depth, and there was no significant difference between the two groups ( P>0.05). Conclusion: The new silk BMT can transfer the symbiotic microbes of the birth canal efficiently, and the optimal preparation parameters were 0.45% hypotonic saline solution and 70% immersion depth.


Asunto(s)
Técnicas Microbiológicas , Microbiota , Seda , Vagina , Bacterias/clasificación , Biodiversidad , Cesárea , Femenino , Humanos , Lactobacillus/fisiología , Técnicas Microbiológicas/métodos , Microbiota/fisiología , Embarazo , Vagina/microbiología
9.
J Environ Manage ; 257: 109983, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31989960

RESUMEN

Stakeholders are critical environmental managers in human-dominated landscapes. In some contexts, stakeholders can be forced to personally act following their own observations and risk perception instead of science recommendation. In particular, biological invasions need rapid control actions to reduce potential socio-ecological impacts, while science-based risk assessments are rather complex and time-delayed. Although they can lead to important detrimental effects on biodiversity, potential time-delayed disconnections between stakeholders' action and science recommendations are rarely studied. Using the case study of western European beekeepers controlling the invasive Asian hornet Vespa velutina nigrithorax for its suspected impact on honey bee colonies, we analysed mechanisms underlying personal actions of stakeholders and how they evolved in science disconnection. Personal actions of stakeholders were causal-effect linked with their risk observation but disconnected to time-delayed science predictions and recommendations. Unfortunately, these science-disconnected actions also led to dramatic impacts on numerous species of the local entomofauna. These results highlight the need to improve mutual risk communication between science and action in the early-stages of management plans to improve the sustainably of stakeholders' practices.


Asunto(s)
Especies Introducidas , Avispas , Animales , Abejas , Biodiversidad , Humanos , Medición de Riesgo
10.
J Environ Manage ; 256: 109919, 2020 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-31989974

RESUMEN

Grasslands are among the most species-rich ecosystems in Europe. However, their biodiversity has become increasingly threatened by land-use and climate change. Here, we analyze Orthoptera assemblage shifts between 1996 and 2017 across three grassland types in the Black Forest (SW Germany) (N = 63): (i) formerly managed wet grasslands which have been frequently abandoned in recent decades (WET) (N = 15); (ii) common pastures which are still traditionally managed by rough grazing (COMMON) (N = 29), and (iii) mesic grasslands which have recently suffered from land-use intensification (MESIC) (N = 19). Both annual and summer temperatures increased during the study period. Orthoptera assemblages strongly responded to the altered environmental conditions in the grasslands. However, effects differed clearly among grassland types. Despite a strong increase in overall species richness in common pastures, neither the Community Farmland Index (CFI) nor the Community Temperature Index (CTI) had changed. In the two other grassland types, the CFI decreased and the CTI increased. The CFI - established here for Orthoptera - helped to disentangle the effects of climate and land-use change on Orthoptera assemblage composition. Based on our study, climate warming has led to biotic homogenization of the Orthoptera assemblages of wet grasslands affected by abandonment, and mesic grasslands affected by land-use intensification towards a dominance of more widespread species. In contrast, common pastures characterized by a high heterogeneity and low-intensity management were more resilient to the effects of climate warming.


Asunto(s)
Pradera , Ortópteros , Animales , Biodiversidad , Ecosistema , Europa (Continente) , Alemania
11.
J Insect Sci ; 20(1)2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31916581

RESUMEN

Termites are one of the key ecosystem engineers in tropical forests where they play a major role in decomposition rates, both above and belowground. The interest in termite ecology and biogeography has increased in the last few decades; however, the lack of comparable data has limited the wider impact of termite research. For Ecuador, termite studies are relatively rare and comparable data that are collected using standardized sampling methods are missing. In this study, we aim to 1) provide comparable data of termite species and feeding-group diversity from two primary forests in Ecuador and 2) explore the differences in termite species and feeding-group diversity between the two forest sites. Sampling took place in the national parks of Yasuní and Podocarpus where three belt transects (100 × 2 m) following Jones and Eggleton (2000) were conducted in each forest. We found that termite species richness was higher in Yasuní (56 species) than in Podocarpus (24 species) and that 57% of the sampled termite genera had never previously been recorded in Ecuador. The inter-site species dissimilarity was almost complete (Bray Curtis (±SD), 0.91 ±â€…0.01), which may have been linked to the difference in tree density and species richness in the two forests. Termite feeding-groups diversity was significantly higher in Yasuní than in Podocarpus with the exception of soil-feeding termites which may have been due to competition between humus- and soil-feeding species.


Asunto(s)
Biodiversidad , Isópteros/fisiología , Parques Recreativos , Animales , Ecuador , Conducta Alimentaria , Bosques
12.
Ying Yong Sheng Tai Xue Bao ; 31(1): 9-16, 2020 Jan.
Artículo en Chino | MEDLINE | ID: mdl-31957375

RESUMEN

Ephemeral plants are a major component of biodiversity in the deserts of Northwest China, with important ecological functions. Information on plant morphological characteristics and biomass accumulation and allocation during different growth stages could enhance our understanding of the functional features and survival strategy of ephemeral plants. We examined the effects of increased precipitation on ephemeral species Eremopyrum distans and Nepeta micrantha in the Gurbantunggut Desert. Changes in morphological characteristics and biomass accumulation and allocation were analyzed under increasing precipitation 30% and 50% treatments. The results showed that increased precipitation 30% and 50% treatments promoted the growth of E. distans, with leaf area and reproductive organ biomass being increased by 14.2%-188.5% and 55.9%, respectively. The effects of increased precipitation on the growth of N. micrantha varied across different growth stages. At leaf expansion stage, increased precipitation promoted growth of N. micrantha, while at fruit ripening stage, increased precipitation 50% treatment reduced leaf area, plant height, and reproduction biomass by 54.9%, 20.5%, 43.2%, respectively. Thus, the responses of the two species to increased precipitation was species-specific. Increased precipitation would change the survival strategies of the two species, with consequence on the species composition and structure of desert community.


Asunto(s)
Clima Desértico , Plantas , Biodiversidad , Biomasa , China
13.
Ying Yong Sheng Tai Xue Bao ; 31(1): 122-128, 2020 Jan.
Artículo en Chino | MEDLINE | ID: mdl-31957388

RESUMEN

Evaluating the impacts of genetically modified crops on biodiversity is a necessary step before their release to the field and obtaining environmental safety certificates. To assess the ecological safety of herbicide-resistant soybean ZUTS-33, we compared arthropod diversity, diseases occurrence, nodule number, and weed diversity through spraying herbicide or water on ZUTS-33, and its parental control receptor HC-3 and main cultivar soybean ZH-13 in a field experiment. The results showed that there was no significant difference of arthropod diversity (number of insects per 100 plants, Shannon index, Simpson index and Pielou index), diseases incidence rates and disease index, nodules and weed diversity between ZUTS-33 and non-genetically modified control soybean HC-3 and ZH-13. Spraying herbicide on ZUTS-33 had no significant effect on arthropod diversity, diseases and rhizobium compared with those treatments of spraying clear water on ZUTS-33, non-genetically modified control HC-3 and ZH-13, and the abundance of weeds were significantly decreased.


Asunto(s)
Herbicidas , Soja , Animales , Biodiversidad , Productos Agrícolas , Plantas Modificadas Genéticamente
14.
Ying Yong Sheng Tai Xue Bao ; 31(1): 340-348, 2020 Jan.
Artículo en Chino | MEDLINE | ID: mdl-31957413

RESUMEN

The relationship between biodiversity and ecosystem services is one of the hot topics in ecological research. The ways that the relationship is applied to the development of ecosystem management and policy have gradually gained attention after the Millennium Ecosystem Services Assessment in 2005. However, applying theoretical understanding of the relationship into practical management still faces challenges. Examining recent progresses may help to guide practices and po-licies. We summarized recent progress in researches on the relationship between biodiversity and ecosystem services in terms of the impacts of biodiversity on single ecosystem service, ecosystem multifunctionality and trade-offs of ecosystem services, as well as how environmental changes affected these relationships. Moreover, we outlined the application of these relationships in nature reserve management, forest management, degraded ecosystem restoration, and agro-ecosystem improvement. We further analyzed the shortcomings in relationship studies and then emphasized that future research and practice trends are the interaction of different biodiversity components and multiple trophic levels on ecosystem services, the coupling effects of environmental changes on the relationships, and practical approaches to biodiversity for improving ecosystem services.


Asunto(s)
Biodiversidad , Ecosistema , Conservación de los Recursos Naturales , Ecología , Bosques
15.
Ambio ; 49(3): 833-847, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31955399

RESUMEN

This review provides a synopsis of the main findings of individual papers in the special issue Terrestrial Biodiversity in a Rapidly Changing Arctic. The special issue was developed to inform the State of the Arctic Terrestrial Biodiversity Report developed by the Circumpolar Biodiversity Monitoring Program (CBMP) of the Conservation of Arctic Flora and Fauna (CAFF), Arctic Council working group. Salient points about the status and trends of Arctic biodiversity and biodiversity monitoring are organized by taxonomic groups: (1) vegetation, (2) invertebrates, (3) mammals, and (4) birds. This is followed by a discussion about commonalities across the collection of papers, for example, that heterogeneity was a predominant pattern of change particularly when assessing global trends for Arctic terrestrial biodiversity. Finally, the need for a comprehensive, integrated, ecosystem-based monitoring program, coupled with targeted research projects deciphering causal patterns, is discussed.


Asunto(s)
Biodiversidad , Ecosistema , Animales , Regiones Árticas , Aves , Invertebrados
16.
Oecologia ; 192(2): 515-527, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31950262

RESUMEN

Biodiversity loss and climate warming are occurring in concert, with potentially profound impacts on ecosystem functioning. We currently know very little about the combined effects of these changes on the links between the community structure, dynamics and the resulting in situ CO2 concentrations in freshwater ecosystems. Here we aimed to determine both individual and combined effects of temperature and non-resource diversity (species inedible for a given consumer) on CO2 concentration. Our analysis further aimed to establish both direct effects on CO2 concentrations and potential indirect effects that occur via changes to the phytoplankton and zooplankton biomasses. Our results showed that there were no interactive effects of changes in temperature and diversity on CO2 concentration in the water. Instead, independent increases in either temperature or non-resource diversity resulted in a substantial reduction in CO2 concentrations, particularly at the highest non-resource diversity. The effects of non-resource diversity and warming on CO2 were indirect, resulting largely from the positive impacts on total biomass of primary producers. Our study is the first to experimentally partition the impacts of temperature and diversity on the consumer-resource dynamics and associated changes to CO2 concentrations. It provides new mechanistic insights into the role of diverse plankton communities for ecosystem functioning and their importance in regulating CO2 dynamics under ongoing climate warming.


Asunto(s)
Dióxido de Carbono , Ecosistema , Animales , Biodiversidad , Biomasa , Agua Dulce , Temperatura Ambiental , Zooplancton
17.
Glob Chang Biol ; 26(1): 119-188, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31891233

RESUMEN

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.


Asunto(s)
Acceso a la Información , Ecosistema , Biodiversidad , Ecología , Plantas
18.
Nature ; 577(7788): 7-8, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31894154
19.
Ecol Lett ; 23(3): 457-466, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31925914

RESUMEN

Rising sea surface temperatures are expected to lead to the loss of phytoplankton biodiversity. However, we currently understand very little about the interactions between warming, loss of phytoplankton diversity and its impact on the oceans' primary production. We experimentally manipulated the species richness of marine phytoplankton communities under a range of warming scenarios, and found that ecosystem production declined more abruptly with species loss in communities exposed to higher temperatures. Species contributing positively to ecosystem production in the warmed treatments were those that had the highest optimal temperatures for photosynthesis, implying that the synergistic impacts of warming and biodiversity loss on ecosystem functioning were mediated by thermal trait variability. As species were lost from the communities, the probability of taxa remaining that could tolerate warming diminished, resulting in abrupt declines in ecosystem production. Our results highlight the potential for synergistic effects of warming and biodiversity loss on marine primary production.


Asunto(s)
Ecosistema , Fitoplancton , Biodiversidad , Biomasa , Océanos y Mares
20.
Ecol Lett ; 23(3): 575-585, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31943698

RESUMEN

Most ecosystems are affected by anthropogenic or natural pulse disturbances, which alter the community composition and functioning for a limited period of time. Whether and how quickly communities recover from such pulses is central to our understanding of biodiversity dynamics and ecosystem organisation, but also to nature conservation and management. Here, we present a meta-analysis of 508 (semi-)natural field experiments globally distributed across marine, terrestrial and freshwater ecosystems. We found recovery to be significant yet incomplete. At the end of the experiments, disturbed treatments resembled controls again when considering abundance (94%), biomass (82%), and univariate diversity measures (88%). Most disturbed treatments did not further depart from control after the pulse, indicating that few studies showed novel trajectories induced by the pulse. Only multivariate community composition on average showed little recovery: disturbed species composition remained dissimilar to the control throughout most experiments. Still, when experiments revealed a higher compositional stability, they tended to also show higher functional stability. Recovery was more complete when systems had high resistance, whereas resilience and resistance were negatively correlated. The overall results were highly consistent across studies, but significant differences between ecosystems and organism groups appeared. Future research on disturbances should aim to understand these differences, but also fill obvious gaps in the empirical assessments for regions (especially the tropics), ecosystems and organisms. In summary, we provide general evidence that (semi-)natural communities can recover from pulse disturbances, but compositional aspects are more vulnerable to long-lasting effects of pulse disturbance than the emergent functions associated to them.


Asunto(s)
Biodiversidad , Ecosistema , Biomasa
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