ANR DUNE Total deposition monitoring of nutrients in
- Slides: 14
ANR DUNE Total deposition monitoring of nutrients in Corsica K. Desboeufs, E. Bon Nguyen, P. Simeoni, S. Chevaillier, F. Dulac, C. Guieu
Deposition Measurements in Corsica – Total deposition measurements – Weekly samplings from March 2008 to October 2011 – Local maintenance by Pasquale Simeoni (National Park of Corsica Region) • Pre-acidification with pure HCl • Rinse with 60 m. L of 0. 2 M HCl solution
Deposition Measurements in Corsica Experimental protocol (in clean room): 1. Weighing before ad after collect total volume + rainfall estimation 2. No filtered part Estimation of particles size distribution 3. Filtration (0. 2 µm) – Analyses of dissolved phase: ICP-AES or MS (majors + trace metals) + IC (Ntot) – Analyses of particulate phase : XRF (Al, As, Co, Ca, Na, K, Mg, P, Pb, Si, Fe, Ti, V, Zn)
Deposition measurement: Results 3. 5 years of total deposition measurement of nutrients and trace metals in Corsica
Deposition measurement: Results N: 30 -124 mg. m-2. y-1 P: 87 -210 mg. m-2. y-1 Si: 150 -270 mg. m-2. y-1
Deposition measurement: Results Bergametti et al. , 1989 Si flux is mainly associated with Saharan dust deposition
Deposition measurement: Results Case of dust mass flux Typical samples of dust event Estimation of dust mass deposition from : -sum of oxides - from Al content (7%) (Guieu et al. , 2010)
Deposition measurement: Results
Deposition measurement: Results (Moulin et al. , JGR, 1998)
Deposition measurement: Results Case of dust mass flux Time-series of dust flux in Corsica Löye-Pilot et al. , 1996; Guieu et al. , 2010; Ternon et al. , 2010 This study The lowest fluxes since eighties, in agreement with no intense event recorded during the sampling period
Deposition measurement: Results Formenti et al. , 2014 2 majors sources of dust: Tunisia-E. Algeria and Morocco-W. Algeria in agreement with the previous works (Bergametti et al. , 1989)
Deposition measurement: Results Case of dust mass flux Identification of event of dust deposition is based on : - Dust is visible on the filter and dust flux > 8 mg/m 2/week (median of flux considering as the background level) + African dust event was identified during the week by : aerosol maps (DREAM, NAAPS), Satellite images (Sea. Wi. FS, MODIS, SEVIRI), air masses trajectory (HYSPLIT), AOD measurements (AERONET) or PM 10 concentrations (Qualitair Corse). SEVIRI TERRA MODIS AOD
Deposition measurement: Results Case of dust mass flux Identification of 32 dust events on 157 sampled weeks: 34% P flux associated to dust deposition 19% N flux associated to dust deposition Large part of other sources? + correlation with Mg and Ca 12% P flux associated to S 54% P flux associated to Knss Ship plume? Domestic fuel? • 10% from Mineral dust (local source? Carbonates? )? • 44% from Biomass burning?
Deposition measurement: Conclusion 3. 5 years of total deposition measurement of nutrients and trace metals in Corsica Dust flux during this peraiod shows the lowest valeus since eighties but dust sources providing Corsica seem the same. Identification of nutrients origins Si flux associated to Saharan dust deposition 19% N flux associated to Sahran dust deposition but no identifiaction of other source: gaseous exchange? P flux is issued for : 34% associated to Sahran dust deposition 12% associated to S deposition 10% associated to mineral dust deposition 44% associated to biomass burning
