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1.
J Environ Manage ; 246: 594-604, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31202827

RESUMO

Peatlands are an important terrestrial carbon store, but disturbance has resulted in the degradation of many peatland ecosystems and caused them to act as a net carbon source. Restoration work is being undertaken but monitoring the success of these schemes can be difficult and costly using traditional field-based methods. A landscape-scale alternative is to use satellite data to assess the condition of peatlands and to estimate gaseous carbon fluxes. In this study we used Moderate Resolution Imaging Spectroradiometer (MODIS) products to model Gross Primary Productivity (GPP) over peatland sites at various stages of restoration. We found that the MOD17A2H GPP product overestimates GPP modelled from data collected by eddy covariance towers situated at two ex-forestry sites undergoing restoration towards blanket bog at the Forsinard Flows RSPB reserve, Scotland, UK (one full year of data), and a near-natural Atlantic blanket bog site in Glencar, Ireland (ten-year data series). We calibrated a Temperature and Greenness (TG) model for the Forsinard sites and found it to be more accurate than the MODIS GPP product at local scale. We also found that inclusion of a wetness factor using the Normalised Difference Water Index (NDWI) improved inter-annual accuracy of the model. This TGWa (annual Temperature, Greenness and Wetness) model was then applied to six control sites comprising near-natural bog across the reserve, and to six sites on which restoration began between 1998 and 2006. GPP from 2005 to 2016 was estimated for each site using the model. The resulting modelled trends are positive at all six restored sites, increasing by approximately 5.5 g C/m2/yr every year since restoration began in the Forsinard Flows reserve. The results suggest that peatland sites undergoing restoration at Forsinard Flows reach the carbon assimilation potential of near-natural bog sites between 5 and 10 years after restoration was begun.


Assuntos
Ecossistema , Fotossíntese , Ciclo do Carbono , Irlanda , Escócia
2.
J Bacteriol ; 159(1): 388-9, 1984 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6330041

RESUMO

Strains of Caulobacter crescentus, Pseudomonas putida, Acinetobacter calcoaceticus, Rhizobium meliloti, and Rhodopseudomonas sphaeroides carrying the kanamycin resistance-encoding transposon Tn5 were 15 to 500 times more resistant to streptomycin than transposon-free strains. The streptomycin resistance determinant, which is separable from the kanamycin resistance determinant of Tn5, was not expressed in Escherichia coli or Klebsiella aerogenes.


Assuntos
Bactérias/genética , Elementos de DNA Transponíveis , Canamicina/toxicidade , Klebsiella pneumoniae/genética , Estreptomicina/toxicidade , Bactérias/efeitos dos fármacos , Resistência Microbiana a Medicamentos , Escherichia coli/genética , Pseudomonas/genética , Rhizobium/genética , Rhodobacter sphaeroides/genética , Especificidade da Espécie
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