climate-hydrology-ecology interactions in glacierized river systems [david hannah]
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Climate-hydrology-ecology interactions
in glacierized river systems
David M. Hannah1, L.E. Brown2 and A. M. Milner1
1School of Geography, Earth and Environmental Sciences,
University of Birmingham, UK. 2School of Geography, University of Leeds, UK.
d.m.hannah@bham.ac.uk
Shrinking glaciers
• Growing evidence indicates glaciers shrinking
• Glacierized basins highly sensitive (most vulnerable) to climate change
(Dyurgerov & Meier, 2005)
atmospheric
circulation
local
climate
energy/ mass
exchange
meltwater generation
and drainage
stream flow
contributions(snow, glacier and groundwater)
physico-chemical
habitat
benthic
communities
Hydrological response?
• Short-term discharge increase (A)
• Longer-term discharge decrease (B C)
• Weaker compensation effect change seasonality
• Glacial/ nival pluvial regime flashier/ inc. disturbance
(Miln
er,
Bro
wn
& H
an
nah
, 2009)
Ecological response?
0 2 4 6 8 10
High
Low
Water temperature (T max)
Chloroperlidae
Leptophlebiidae (NZ)NemouridaeLeuctridae
HeptageniidaeRhyacophilidaeChironominae
Limnephilidae
PerlodidaeTaenioplerygidae
BaetidaeSimuliidaeEmpididae
OligochaetaTipulidae
OrthocladiinaeDiamesinae
esp Diamesa
(Milner et al., 2001)
Aims 1. To present a novel, alternative glacier river classification
tool (Alpine RIver and Stream Ecosystem = ARISE)
2. To advance hypotheses concerning impact of climate
change on glacierized river system hydrology and
ecology
3. To identify future research imperatives and directions
Alternative glacier river classification (ARISE)
• Previous approaches based mainly on water temperature
• ARISE uses quantified water source contributions
different physicochemical habitat benthic communities
• No quantitative relationships between water source
contributions and stream macroinvertebrates
(Bro
wn
, H
an
nah
& M
iln
er,
2003;
2009)
1. Effect of reduced
meltwater contribution on
community structure?
2. Individual species
response (bioindicators)?
3. How vulnerable is
biodiversity to shrinking
snowpacks and glaciers?
Taillon-Gabiétous basin, Pyrenees
• > decade of research
• 7.7 km2
• 1800-3022 masl
• steep slopes 30-70°
• meadow, above treeline
• 5% permanent snow/ ice
• 2 glaciers
• snowpacks <2700 masl
• karst system
• hillslope/ alluvial aquifers
Spain
France
N
10m
C
A
B
• Water samples:
weekly (high and low flow) at 3 river gauges
monthly samples of groundwater/ hillslope tributaries
snow pits
• EMMA determine water source contributions (Brown, Hannah et al., 2006)
0
100
200
300
400
500
600
700
800
0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 2.2
Si (ppm)
SO
42- (
µe
qL
-1)
'Distributed'
'Quickflow'
'Groundwater'
Upper Site
Site A
Site B
Site C
Groundwater Subglacial
distributed
Dilute snow- and ice-melt
0 50
50 50
0
0
100
100
100
Snow
Methods: water sourcing
(Bro
wn
, H
an
na
h &
Mil
ner
, 2
00
9)
A: glacial
B: groundwater
C: confluence
2002 2003
Methods: macroinvertebrates
• 5 0.1m2 Surber samples (250µm
mesh)
• Collected at each site bi-weekly
• Preserved in 4% formalin, then
sorted in the laboratory
• Identification to species level,
where possible
A
B
C
• Meltwater contribution = dilute quickflow + distributed glacial
Proportion meltwater
Proportion meltwater
0
10
20
30
40
50
60
70
0 0.2 0.4 0.6 0.8 1
Ta
xo
no
mic
Ric
hn
ess
(a)
y = -50.35x + 79.89
R = -0.769
1
10
100
1000
10000
100000
0 0.2 0.4 0.6 0.8 1
To
tal A
bu
nd
an
ce
(b)
y = -2.12x + 4.74
R = -0.855
0
5
10
15
20
25
0 0.2 0.4 0.6 0.8 1
No
. E
PT
Ge
ne
ra
(c)
y = -23.25x + 29.93
R = -0.844
Significant increases in:
taxonomic richness
total abundance
mayflies, stoneflies, caddisflies
with decreasing
meltwater contributions
0
20
40
60
80
100
120
140
0 0.2 0.4 0.6 0.8 1
Ab
un
da
nce
(a)
Habroleptoides
berthelemyi
0
50
100
150
200
250
300
350
0 0.2 0.4 0.6 0.8 1
Ab
un
da
nce
(b)
Perla
grandis
0
50
100
150
200
250
300
350
400
0 0.2 0.4 0.6 0.8 1
Ab
un
da
nce
(c)
Rhithrogena
spp.
Proportion meltwater
• Macroinvertebrates as potential indicators of climate change
0
200
400
600
800
1000
1200
0 0.2 0.4 0.6 0.8 1
Ab
un
da
nce
(b)
Diamesa
latitarsis spp.
0
50
100
150
200
250
0 0.2 0.4 0.6 0.8 1
Ab
un
da
nce
(a)
Rhyacophila
angelieri
• Potential loss of endemic species biodiversity and
conservation implications
Proportion meltwater
Response to shrinking glaciers?
In the long term:
• Decreases in meltwater contributions increased
taxonomic richness/ diversity in streams = higher alpha
diversity (within-stream)
But…
• Decreases in meltwater contributions lower habitat
heterogeneity = lower beta diversity (between-stream)
• Local extinction of some species (e.g. Rhyacophila
angelieri) = lower gamma diversity (basin/ region)
Validation in other glacierized basins
Rob Roy, New Zealand
0
50
100
150
200
250
300
350
R1 R2 R3
Mean
ab
un
dan
ce (
ind
ivid
uals
m-2
)
0
50
100
150
200
250
300
R1 R2 R3M
ean
ab
un
dan
ce (
ind
ivid
uals
m-2
) Hydrobiosisspp.
Costachoremaspp.
Nesameletusaustrinus
Zelandoperlaspp.
Zelandobiusspp.
Deleatidiumangustum
Deleatidiumcornutum
0
50
100
R1 R2 R3
Me
an
ab
un
da
nc
e (
ind
ivid
ua
ls m
-2)
Neocupirahudsoni grp.
Hydora spp.
Eukiefferiellaspp.
Mauridiamesaspp.
Diptera & Coleoptera
EPT taxa
Individuals
Validation in other glacierized basins
Kårsavagge, nr. Abisko, Sweden
K1 K2 K4
K3
K5
K6
K7K9
K8
N
Abisko River
B1-B12Watershed
Boun
dary
of A
bisk
oN
atio
nal P
ark
2km
K1 K2 K4
K3
K5
K6
K7K9
K8
N
Abisko River
B1-B12Watershed
Boun
dary
of A
bisk
oN
atio
nal P
ark
K1 K2 K4
K3
K5
K6
K7K9
K8
N
Abisko River
B1-B12Watershed
K1 K2 K4
K3
K5
K6
K7K9
K8
N
Abisko River
K1 K2 K4
K3
K5
K6
K7K9
K8
N
Abisko River
B1-B12Watershed
Boun
dary
of A
bisk
oN
atio
nal P
ark
2km
Validation in other glacierized basins
Kårsavagge, nr. Abisko, Sweden
No
. m
acro
invert
eb
rate
fam
ilie
s
hillslopes/ groundwater
Longitudinal
Lateral
Concluding thoughts and future research
• Integrated, long-term research into the climate-hydrology-
ecology cascade in other glacierized river basins is vital
• Interdisciplinary science is fundamental:
to predict river hydrology and ecology under scenarios
of future climate/ variability
to assess the utility of glacierized river systems as
indicators of global change
to develop conservation strategies for these fragile
ecosystems atmospheric
circulation
local
climate
energy/ mass
exchange
meltwater generation
and drainage
stream flow
contributions(snow, glacier and groundwater)
physico-chemical
habitat
benthic
communities
• ARISE useful tool but requires wider
evaluation
• Shrinking glaciers high, urgent
importance quantify and model
climate-hydrology-ecology links
Acknowledgements
NATURAL
ENVIRONMENT
RESEARCH COUNCIL
ABISKO SCIENTIFIC
RESEARCH STATION
THE ROYAL SWEDISH
ACADEMY OF SCIENCES
Sarah Cadbury
Chris Mellor
Barney Smith
Debbie Snook
Climate-hydrology-ecology interactions
in glacierized river systems
David M. Hannah1, L.E. Brown2 and A. M. Milner1
1School of Geography, Earth and Environmental Sciences,
University of Birmingham, UK. 2School of Geography, University of Leeds, UK.
d.m.hannah@bham.ac.uk
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