Diatoms as a paleoproductivity proxy in the NW Iberian coastal upwelling system (NE Atlantic)

The objective of the current work is to improve our understanding of how water column diatom's abundance and assemblage composition is seasonally transferred from the photic zone to seafloor sediments. To address this, we used a dataset derived from water column, sediment trap and surface sediment samples recovered in the NW Iberian coastal upwelling system. Diatom fluxes (2.2 (+/- 5.6) 10(6) valves m(-2) d(-1)) represented the majority of the siliceous microorganisms sinking out from the photic zone during all studied years and showed seasonal variability. Contrasting results between water column and sediment trap diatom abundances were found during downwelling periods, as shown by the unexpectedly high diatom export signals when diatom- derived primary production achieved their minimum levels. They were principally related to surface sediment remobilization and intense Minho and Douro river discharge that constitute an additional source of particulate matter to the inner continental shelf. In fact, contributions of allochthonous particles to the sinking material were confirmed by the significant increase of both benthic and freshwater diatoms in the sediment trap assemblage. In contrast, we found that most of the living diatom species blooming during highly productive upwelling periods were dissolved during sinking, and only those resistant to dissolution and the Chaetoceros and Leptocylindrus spp. resting spores were susceptible to being exported and buried. Fur-thermore, Chaetoceros spp. dominate during spring-early summer, when persistent northerly winds lead to the upwelling of nutrient-rich waters on the shelf, while Leptocylindrus spp. appear associated with late-summer upwelling relaxation, characterized by water column stratification and nutrient depletion. These findings evidence that the contributions of these diatom genera to the sediment's total marine diatom assemblage should allow for the reconstruction of different past upwelling regimes.CAIBEX [CTM2007-66408-C02-01/MAR]; REIMAGE [CTM2011-30155-C03-03]; Spanish Government, EXCAPA project [10MDS402013PR]; Xunta de Galicia; EU FEDER [INTERREG 2009/2011-0313/RAIA/E]; RAIA. co [INTERREG2011/2013-052/RAIA.co/1E]; CALIBERIA project [PTDC/MAR/102045/2008]; Fundacao para a Ciencia e a Tecnologia (FCT-Portugal) [COMPETE/FEDER-FCOMP01-0124-FEDER-010599]; Xunta de Galicia (Spain) [SFRH/BPD/111433/2015]; FCT (Portugal) [SFRH/BPD/111433/2015]; [SFRH/BD/88439/2012

Limitations and opportunities of spatial planning to enhance wildfire risk reduction: evidence from Portugal

Spatial planning potential for reducing natural risks including wildfires is widely recognized. This research is focused on Portugal, a wildfire-prone country in southern Europe, where the competencies for spatial planning lie on four geographical levels: (i) the national and regional levels, with a strategic nature, set the general goals or the agenda of principles for spatial planning and (ii) the inter-municipal and municipal levels use regulative land-use planning instruments. There is a trend to bring together spatial planning and wildfire management policies. Thus, this paper aims to identify which are the main difficulties and which are the major opportunities, regarding the implementation of the new Integrated Management System for Rural Fires (IMSRF) and the challenge of integrating wildfire risk reduction in the Portuguese spatial planning framework. Through a survey of municipal professionals with experience in applying the legislation of both policies, the major difficulties and the opportunities of alignment of these two spheres are identified, which can be extrapolated for the whole country or countries in a similar context