SNOW-DUSTStudio degli effetti chimici e biogeografici delle avvezioni di polveri

sahariane sul Ghiacciaio del Calderone (Gran Sasso d’Italia)

David Cappelletti1,2,*, Ermanno Federici1, Chiara Petroselli1, Roberta Selvaggi1, Stefano Crocchianti1,

Beatrice Moroni1, Elena Montalbani1, Pinuccio D’Aquila3, Massimo Pecci2,4

1Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia 2Comitato Glaciologico Italiano, 3Geologo, CNSAS-CAI Chieti, , 4CAI Roma

*david.cappelletti@unipg.it

desert dust: an efficient carrier

of pollutants and bacteria

adapted from Kellogg et al (2006)

desert dust: an efficient carrier

of pollutants and bacteria

adapted from Kellogg et al (2006)

M.Martano SDS-WAS stationSand & Dust Warning Alert System (WMO)

M.Martano SDS-WAS stationSand & Dust Warning Alert System (WMO)

Zn

Cr

Ni

Cu

V

Mn

Co

Ca

Ti

Fe

flu

orid

e

ch

lorid

e

nitra

te

ph

osp

ha

te

su

lph

ate

OC

EC

0.001

0.01

0.1

1

sa

mp

le / P

M_

MM

_2

10

51

4

20.02.14

04.04.14

22.05.14

24.06.14

15.10.14

07.11.14

01.12.14

always larger than the

high levels of Fe, Ti, Cahigh levels of dust loads

M.Martano SDS-WAS stationSand & Dust Warning Alert System (WMO)

specific bacteria communities associated with PAH

Calderone glacier

(al Gran Sasso d’Italia)

may 2010

end the ablation season

sept 2011 sept 2012

monitoraggio (2008-2017)

idrocarburi policiclici aromatici

Saharan dust

inverno-primavera estate-autunno

impact on the snow surface

giu 2013

impact on the snowpack

Sahariana febbraio

Sahariana gennaio

feb 2014

elemental vs organic carbon

present & future studies

PROGETTO SNOWDUST – ROMA, 5 OTTOBRE 2017

Ermanno Federici

Laboratori di Microbiologia Applicata e AmbientaleDipartimento di Chimica, Biologia e Biotecnologie

Effects of Desert Dust Depositions on the

Microbiota of the Calderone Glacier

Culture-Independent Characterization of

Microbial Communities

High complexity Culture-Based Approach

Microbial diversity

Metagenomic DNA

Next Generation Sequencing

Bacterial Diversity in the Glacier:

Clean and Dust-Impacted Snow

Bacterial Diversity in the Glacier:

Melting (h) and Source (l) Water

β-Diversity Among Dust-Impacted Snow,

Clean Snow and Water Samples

Dendrogram based on Bray–Curtis distances between microbial communities of Clean Snow (Sn), Saharan-impacted snow (SH) and water samples (Wat). Snow was collected on the surface (s), median (m) and deep (d)layer of the snow pit. Water samples were melting directly on the glacier (h) and from a natural source (l).

β-Diversity Among Dust-Impacted Snow,

Clean Snow and Water Samples

β-Diversity Among Dust-Impacted Snow,

Clean Snow and Water Samples

The Monte Martano Sampling Site

Distribution of the most abundant bacterial genera (average abundance higher than 0.5%) in the PM10 samples.

Bacterial Communities in PM10 Samples

Impact of Saharan Dust Intrusions on the

Bacterial Diversity of the Glacier

Average distribution of top-abundant bacterial genera (more than 1% of total) of particulate matter collectedduring Saharan intrusion (SH), in the four different groups of samples (clean snow, Saharan-impacted snow,melting water from the glacier and source water)

Impact of Saharan Dust Intrusions on the

Bacterial Diversity of the Glacier

Genus SH Clean SnowSH-

impacted

Melting

Water

Source

Water

Hymenobacter 3,99% 6,02% 19,64% 1,17% 0,31%

Massilia 2,42% 1,19% 19,40% 0,99% 1,25%

Acinetobacter 1,23% 6,73% 11,03% 0,01% 1,44%

Pseudomonas 1,08% 0,23% 1,62% 1,04% 15,36%

Naxibacter 1,81% 3,40% 1,59% 7,51% 0,85%

Stenotrophomonas 6,98% 0,31% 1,41% 0,08% 0,21%

Acidovorax 7,78% 0,50% 1,08% 0,48% 2,21%

Streptophyta 3,38% 0,20% 1,05% 0,00% 0,24%

Sphingomonas 12,97% 0,34% 0,84% 0,23% 0,29%

Bacillus 2,30% 0,21% 0,81% 0,00% 0,02%

Adhaeribacter 3,14% 0,06% 0,58% 0,00% 0,02%

Geodermatophilus 0,75% 0,09% 0,58% 0,00% 0,00%

Microvirga 0,92% 0,05% 0,49% 0,00% 0,00%

Rubellimicrobium 1,05% 0,54% 0,47% 0,03% 0,00%

Domibacillus 1,74% 0,10% 0,29% 0,00% 0,00%

Phenylobacterium 1,32% 0,18% 0,28% 0,19% 0,12%

Staphylococcus 0,82% 0,04% 0,22% 0,00% 0,01%

Pontibacter 0,91% 0,01% 0,16% 0,00% 0,00%

Porphyrobacter 0,77% 0,03% 0,11% 0,08% 0,02%

Methylobacterium 2,79% 0,03% 0,10% 0,00% 0,06%

Dyadobacter 0,54% 0,02% 0,06% 0,00% 0,00%

Mycobacterium 0,75% 0,01% 0,05% 0,01% 0,06%

Pedobacter 1,06% 0,29% 0,04% 0,71% 0,07%

Rhizobium 0,76% 0,00% 0,02% 0,00% 0,00%

Clostridium XI 0,87% 0,00% 0,01% 0,00% 0,01%

Lactobacillus 0,89% 0,00% 0,01% 0,00% 0,01%

Pseudoxanthomonas 0,60% 0,00% 0,00% 0,01% 0,05%

27 bacterial populations

representing a “core”

dust microbiome

12 of these populations

are also abundant in the

SH-impacted snow

Conclusions

• The striking differences observed between the bacterial communities

of the two groups of the snow samples, clearly indicated that Saharan

dust deposited in the Calderone glacier strongly impacted the bacterial

diversity inthe snow.

• Several of the bacterial populations that were enriched in the Saharan-

impacted snow were also abundant in PM collected during African

dust intrusions, confirming that these airborne, dust-carried bacteria

were able to colonize the glacier.

• Some of the deposited bacteria were also retrieved in the water from

the glacier, suggesting that the bacteria transported over the

Mediterranean from Sahara can have the potential to impact the entire

mountain environment.

Acknowledgments

� Dipartimento di Chimica, Biologia

e Biotecnologie, Università di Perugia

Prof. D. Cappelletti, Dr. B. Moroni, Dr. C.

Petroselli, Dr. G. La Porta,

� Dipartimento di Scienze Ambientali e

della Terra, Università di Milano Bicocca

Prof. A. Franzetti, Dr. I. Gandolfi

ELENA MONTALBANI