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21.
Sergio Cinnirella Nicola Pirrone Alessia Allegrini Daniela Guglietta 《Environmental Fluid Mechanics》2008,8(2):129-145
Mercury emissions from forest fires in countries bordering the Mediterranean Sea have been estimated on the basis of satellite
observations for the year 2006. The assessment has been done by means of the Moderate Resolution Imaging Spectroradiometer
(MODIS) products (MOD12Q1, MOD14A2, MOD15A2, MOD44B). Estimates show that wild fires have burnt 310,268 ha in the Region,
affecting by 45% the Mixed Forest and by 37% the Evergreen Needleleaf Forest and the Evergreen Broadleaf Forest. The amount
of biomass burned was about 66,000 Mg for the Evergreen Needleleaf Forest, 72,000 Mg for the Evergreen Broadleaf Forest and
196,000 Mg for the Mixed Forest. The total amount of mercury released to the atmosphere in the Mediterranean countries accounted
for 4.3 Mg year−1 with Italy, France, Austria, Bulgaria, Algeria, Spain and Croatia being the most contributing countries with annual emission
ranging from 330 to 970 kg year−1. The maximum release of Gaseous Elemental Mercury (GEM) and particulate mercury (Hg(p)) in the region occurred in July with
1,218 kg. The uncertainty of our estimates is comparable with that associated to current assessments of mercury emissions
from major industrial sources. 相似文献
22.
Paola Pasolini Chiara Ragazzini Zelia Zaccaro Alessia Cariani Giorgia Ferrara Elena G. Gonzalez Monica Landi Ilaria Milano Marco Stagioni Ilaria Guarniero Fausto Tinti 《Marine Biology》2011,158(10):2173-2186
The European Raja clavata and the South African R. straeleni are marine skates which exhibit highly conserved morphological and ecological traits. Owing to this, taxonomic and evolutionary relationships between the two taxa have not yet fully elucidated. Here, we have tested the hypothesis that restricted gene flow and genetic divergence between these taxa might be associated with climatic/oceanographic discontinuities by surveying genetic variation in ten geographical samples at control region (CR) and amplified fragment length polymorphism (AFLP) loci. The clustering of CR haplotypes in two reciprocally monophyletic clades consistent with taxon zoogeography and the significant AFLP F values between the European and South African populations indicated the two taxa as recently diverged peripatric sibling species. Within each species, significant spatial genetic heterogeneity among samples at both markers revealed population structuring. We argued that structured populations and isolated sibling species might represent two stages of geographical speciation. 相似文献