Beetles versus Rolling Stones carabids on ...

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Beetles versus Rolling Stones carabids on cryoperturbed fellfields. M. Gobbi1, C. Compostella2, D. Tampucci2 & M. Caccianiga2. 1 MUSE-Science Museum, ...
Beetles versus Rolling Stones carabids on cryoperturbed fellfields

M. Gobbi1, C. Compostella2, D. Tampucci 2 & M. Caccianiga 2 1 MUSE-Science

Museum, Trento, Italy 2 University of Milan, Milano, Italy

Background Challenge in alpine biogeography determine how cold-adapted species will respond to climate changes To avoid extinction, cold-adapted species may respond to climate change by: 1. migrating to new areas (mountain peaks or chasing retreating glaciers) 2. adapting through phenotypic plasticity and adaptive evolution to the new environmental conditions 3. search refugium areas (e.g. caves during the Pleistoncene)

Background Gravitational lanforms

Rocky landforms

Ice-related landforms

Cryperturbed fellfield scree slope

debris cone

Background: cryoperturbed fellfields Ice-debris landforms moving or creeping due to ice deformation. Debris-covered glaciers (DCGs) and rock glaciers (RGs), characterize the glacial and periglacial mountain environments. These climate-related landforms are poorly known from the ecological point of view even if suitable habitats for life.

Debris-covered glacier

1800 m asl

Rock Glacier Rocky debris

Ice

Main rationale May cryperturbed fellfields promote the long-term survival of cold-adapted carabids when the surrounding habitats become climatically unfavorable?

Goal of our research Describe the carabid populations living on DCGs and RGs of the Italian Alps and to compare them with currently ice-free neigbouring blocky landforms.

Study system and sampling design: Debris-covered glaciers (DCGs)

1800 m asl

1800 m asl

Miage Glacier (Mount Blanc Massif; W-Alps)

Belvedere Glacier (Monte Rosa Massif; W-Alps)

2600 m asl

Amola Glacier (Presanella Massif; E-Alps)

Study system and sampling design: Rock Glaciers (RGs) Amola (E-Alps) – 2400 m asl

Vedrettino (C-Alps) – 2570 m asl

Lago Lungo (C-Alps) – 2470 m asl

Col d’Olen (W-Alps) – 2710 m asl

Sampling design and environmental covariates Carabids • 15 pitfall traps for each landform (RG or DCG, scress slope, stable slope) • Recovering interval: 20 days • Recovers number: 3-5 Soil • • • •

Grain size distribution Organic matter content Calcium carbonate content pH

Vegetation • Plot surface: 25 m² • Cover resolution: 5 % • Taxa: mosses and vascular plants

from: Gobbi et al. (2011) The Holocene

Results: Miage DCG

Forest/grassland assemblages Boundary zone (treeline) Species of rocky and subglacial habitats

Altitude (m)

Vegetation cover (%)

Debris thickness (cm)

Species richness

Sites

Rugathodes bellicosus

Aculepeira ceropegia

Pisaura mirabilis

Nebria angusticollis

Drassodex heeri

Pardosa saturatior

Ozyptila rauda

Xysticus lanio

Walckenaeria antica

Drassodes lapidosus

Alopecosa sulzeri

Nebria picea

Calathus melanocephalus

Amara erratica

Cychrus attenuatus

Xysticus cristatus

Xerolycosa nemoralis

Amaurobius fenestralis

Calathus micropterus

Leistus nitidus

Pterostichus multipunctatus

Platycarabus depressus

Zelotes devotus

Pardosa gr. lugubris

Gnaphosa badia

from: Gobbi et al. (2011) The Holocene

E 8 >80 90 1830 F 12 >80 100 1640 D 5 40 15 1850 C 5 35 10 1870 A 5 26 0 2150 B 3 24 0 2230

assemblages turnover EA observed 522 EA mean 299.34 dev 105.66 P 0.035

2000m

2100m 1900m

Vegetation cover (%) Altitude (m)

90 100 15 10 0 0 1830 1640 1850 1870 2150 2230

2200m

1800m

from: Gobbi et al. (2011) The Holocene

Species richness Debris thickness (cm)

Sites

Rugathodes bellicosus

Aculepeira ceropegia

Pisaura mirabilis

Nebria angusticollis

Drassodex heeri

Pardosa saturatior

Ozyptila rauda

Xysticus lanio

Walckenaeria antica

Drassodes lapidosus

Alopecosa sulzeri

Nebria picea

Calathus melanocephalus

Amara erratica

Cychrus attenuatus

Xysticus cristatus

Xerolycosa nemoralis

Amaurobius fenestralis

Calathus micropterus

Leistus nitidus

Pterostichus multipunctatus

Platycarabus depressus

Zelotes devotus

Pardosa gr. lugubris

Gnaphosa badia

E 8 >80 F 12 >80 D 5 40 C 5 35 A 5 26 B 3 24

Results: Belvedere DCG

Glacial surge (2001-2002): short-lived events where a glacier advance moving at velocities up to 100 times faster than normal.

Results: Amola DCG Annual mean temperature in the supraglacial debris was 0.5 °C (datalogger located at 10 cm depth).

DCG hosts female-biased population of Nebria germari, a typical walking coloniser, and olfactory and nocturnal predator with surface running larvae (mainly observed under the stones located on the glacier).

Detectability of Nebria germari showed a negative relationship with gravel proportion in the soil, thus some individuals can remain undetected in deep soils.

Results: RG Amola – 2400 m asl

from: Gobbi et al. (2014) The Holocene

Carabus adamellicola Pterostichus multipunctatus Carabus depressus Bembidion bipunctatum Cymindis vaporariorum

Results: RG Lago Lungo – 2470 m asl O. castanea 3,16

O. castanea

2,58

C. attenuatus C. vaporariorum C. problematicus O. castanea

1,16

Results: RG Vedrettino – 2570 m asl O. castanea 3,33

O. castanea 3,66

O. castanea

0,33

C. sylvestris C. vaporariorum

Results: RG Col d’Olen – 2710 m asl O. castanea

O. castanea

O. castanea 0,15

0,1

C. concolor C. cordicollis A. quenseli

0,1

C. concolor A. quenseli

B. glaciale

Take home concepts: Debris covered glaciers 1. DCGs host permanent, populations of Oreonebria angusticollis (W-Alps), and Nebria germari (E-Alps), due to the presence of stony debris with interstitial ice. 2. The species collected on DCGs with tongue descending down the treeline are able to survive below their average altitudinal distribution thanks to the cold and wet microclimate conditions between the stones.

Take home concepts: Rock glaciers 1. RGs host permanent populations of coldadapted species [Oreonebria castanea (W,CAlps), O. angustata and Nebria germari (E-Alps)] due to the precence of deep ice-core rocky debris. 2. The local climatic condition, and the elevation of each RGs drives the presence of the species also on the ice-free neigbouring blocky landforms.

p=0,017

Conclusions 1. Our results allow to hypothesize that in the present interglacial period DCGs and RGs could act as refugium habitats for cold-adapted carabids as a consequence of their microclimate features and thermal inertia.

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Thanks for you attention!

Acknowledgements: Valeria Lencioni, Roberto Seppi, Manuela Pelfini, Claudio Smiraglia, Guglielmina Diolaiuti, Roberto Azzoni, Giacomo Boffa, Clara Citterio, Ilaria A. Muzzolon, Chiara Maffioletti, Teresa Boscolo, Luca Pedrotti, Simone Tenan, Stelvio National Park.