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ReFFECT:
Restoration of Headwater Streams: Combining
Ecological, Hydrological and Socioeconomical
Perspectives
Jukka Aroviita
Finnish Environment Institute (SYKE), Freshwater Centre
The ReFFECT Consortium:
University of Oulu, Stream Ecology: Timo Muotka, Pauliina Louhi, et al
University of Oulu, Hydrology: Björn Klöve, Hannu Marttila, et al.
SYKE: Jukka Aroviita, Jarno Turunen, Virpi Lehtoranta, Sari Väisänen et al.
+ State Forest Enterprise (Metsähallitus): Pirkko-Liisa Luhta et al.
Sustainable Governance of Aquatic Resources Research Programme (AKVA) - Final Symposium, 9 Dec 2016, Helsinki
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Lakes Streams
Uomaverkosto: SYKE, ELY-keskukset
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© Vesa Kuusava, Ympäristöhallinnon kuvapankki; Maria
Rajakallio Syke; Oskari Härmä / e-Oppi Oy (peda.net)
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http://www.ymparisto.fi/fi-FI/Kartat_ja_tilastot/Vesistojen_ravinnekuormitus_ja_luonnon_huuhtouma
59% of phosphorus comes from agriculture
AGRICULTURE
FORESTRY
POINT
SOURCES
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Roads
Drainage networks
Harvest
Harvest
Stream
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50 km
55 % of peatlands in Finland have been drained to enhance forest growth
Drained peatlands
Lakes
Undrained peatlands
or mineral lands Soiden ojitustilanne: SYKE (pohjautuu MML aineistoon), Uomaverkosto:
SYKE, ELY-keskukset; Oskari Härmä / e-Oppi Oy (peda.net)
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Sedimentation causes
biodiversity loss in streams
Turunen et al. Differential responses by stream and
riparian biodiversity to restoration of forestry-impacted
streams. Submitted.
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Sedimentation may also modify
functions and trophic cascades in
streams
Louhi et al. 2016. Sediment addition reduces the
importance of predation on ecosystem functions in
experimental stream channels. Canadian Journal of
Fisheries and Aquatic Sciences 73: 1–9.
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ReFFECT:
How to improve the status of
streams effectively?
2. Disentan-
gle stressor effects.
3.
Effects of different
restoration methods.
4. Quantify stressor
and habitat effects.
1.
Explore public values.
=> Correlative
analyses using
large-scale
monitoring
data.
=> Questionnaires
on appreciation
and WTP.
=> Field surveys in
restored, stressed
and natural streams.
=> Mesocosm
experiments
in artificial
channels.
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A survey in 2014
● 1,782 inhabitants
● 39 % response rate
3 groups:
● Residents 33%
● Forest owners 50%
● Forest entrepreneurs 17%
Appreciation of ecosystem
services and restoration of forest
streams
1.
Public values and willingness
to pay.
Lehtoranta et al. Public values for stream restoration in forested watersheds: Does land ownership or preference
uncertainty matter? Submitted.
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Residents and forest owners agreed more that:
● Restoration is needed
● Current condition is not good
68% of the respondents were willing to pay
something, on average 10–22 € annually
Forest entrepreneurs agreed more that:
● Damage exaggerated
● Current condition OK
Differences in thoughts and valuing 1.
Public values and willingness
to pay.
Lehtoranta et al. Public values for stream restoration in forested watersheds: Does land ownership or preference
uncertainty matter? Submitted.
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WTP explained by interest to flood mitigation,
trout conservation and water quality issues.
But not by biological diversity.
Difference in appreciation: “Appreciates very
much”:
○ Clean water: 70 %
○ Biological diversity: 25 %
=> Forest owners & entrepreneurs should be
more involved, and at early stages
=> Need to “sell” restoration programmes in
laymans terms
WTP and appreciation 1.
Public values and willingness
to pay.
Lehtoranta et al. Public values for stream restoration in forested watersheds: Does land ownership or preference
uncertainty matter? Submitted.
Conclusions
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Stream restoration has traditionally
focused on channel morphology
But: ecological responses often weak, if
any
=> What are the independent effects of
diffuse pollution and morphological
channel alteration on stream biota?
How to prioritize management actions? 2. Disentan-
gling stressor effects.
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Reference, no stressors HyMo altered, no diffuse pollution
Diffuse pollution,
no HyMo alteration
Both stressors present
2. Disentan-
gling stressor effects.
http://www.syke.fi/hankkeet/maamet
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Even at low stressor levels: Agricultural
diffuse pollution much worse than
HyMo-changes
2. Disentan-
gling stressor effects.
Turunen et al. 2016. Disentangling the responses of boreal stream assemblages to low stressor levels of diffuse
pollution and altered channel morphology. Science of the Total Environment 544: 954–962.
Macrophytes
Reference Hydromorphological alteration Diffuse nutrient pollution Both stressors
Diatoms Benthic fauna
NMS 1
NM
S 2
N=91 streams
18-24 per ”treatment”
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=> Mitigation of diffuse pollution of
nutrients and organic matter from
catchments should be a priority.
Conclusion for management:
Turunen et al. 2016. Disentangling the responses of boreal stream assemblages to low stressor levels of diffuse
pollution and altered channel morphology. Science of the Total Environment 544: 954–962.
2. Disentan-
gling stressor effects.
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Turunen et al. Differential responses by stream and riparian biodiversity to restoration of forestry-impacted streams. Submitted.
Boulder restoration
Headwater stream restoration, two
approaches:
3.
Effects of different
restoration methods.
Wood restoration
33 streams in River Iijoki catcment:
- Near-natural reference streams
- Sediment-stressed from drainage (IMP)
- Stressed, restored mainly with boulders
- Stressed, restored mainly with wood
3-7 yrs after restoration
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3.
Effects of different
restoration methods.
Boulder restoration increased
aquatic bryophyte richness
while wood restoration did not.
Wood restoration altered riparian
vegetation towards near-natural
communities.
Turunen et al. Differential responses by stream and riparian biodiversity to restoration of forestry-impacted streams. Submitted.
Unpublished figure not
shown
Unpublished figure not
shown
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3.
Effects of different
restoration methods.
Turunen et al. Differential responses by stream and riparian biodiversity to restoration of forestry-impacted streams. Submitted.
Marttila et al. Restoration with wooden debris increase transient storage in boreal headwater streams. manuscript.
Boulder restoration decreased
fine sediment cover while
wood restoration did not.
Wood restoration increased hydraulic
retention to near-natural level.
Unpublished figure not
shown
Unpublished figure not
shown
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3.
Effects of different
restoration methods.
Benthic fauna showed signs of
recovery in boulder restored streams.
Turunen et al. Differential responses by stream and riparian biodiversity to restoration of forestry-impacted streams. Submitted.
Unpublished figure not
shown
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4. Quantifying
stressor and habitat
effects.
Mosses decrease the harmful
sediment effects.
Turunen et al. Sedimentation, habitat loss and connectivity as drivers of biodiversity change in boreal streams? In preparation.
Unpublished figure not
shown
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● Biotic responses: taxon-specific and slow to
emerge
● Boulder restoration => Mosses
● Wood restoration => Hydrology => riparian zone
● Streams are tightly linked to the riparian zone.
Flooding is natural.
● In long term: Self-sustaining loop back to
stream?
Conclusions
3.
Effects of different
restoration methods.
4. Quantifying
stressor and habitat
effects.
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ReFFECT:
How to improve status of streams
effectively?
2. Mitigate loading from catchment.
3.
Use stones AND natural
wood.
4. Mosses and natural
riparian zone key to recovery.
1. Involve forestry,
”sell” restoration.
Public
values
Field surveys
Experi-
ments
Large-
scale data