Climate change can cause loss of important ice dynamics in streams

Climate change can cause loss of important ice dynamics in streams
Lovisa Lind has inventoried ice and winter conditions along tributaries to the Vindel River in northern Sweden.

In her thesis, Lovisa Lind shows that ice and winter floods are important natural disturbances for maintaining species-rich riparian zones along northern watercourses. If the climate becomes warmer this disturbance might be lost. This could potentially lead to a less diverse riparian zone. She defends her thesis at Umeå University on Friday 27 February.

Riparian forests are important as they supply habitat, store carbon, provide shading, and filter water. We already know that and winter floods are significant factors for vegetation and wildlife in this region.

During cold winter days, frazil ice (tiny ice particles) forms in the super-cooled water of open turbulent stream reaches. Frazil ice has adhesive features and may attach to submerged boulders and other objects in the water, forming anchor ice. As a consequence, water can be dammed by the anchor ice causing flooding and ice growth in the riparian zone. When the air temperature rises the anchor ice detaches, floats away and might jam up and lead to new floods and even more ice – the stream has become an ice machine.

In her thesis, Lovisa Lind has investigated which factors control ice formation in northern watercourses, and how and to what degree ice and winter floods affect the vegetation along streams. She has inventoried ice and winter conditions along tributaries to the Vindel River in northern Sweden and related them to differences in vegetation.

Her results show that turbulent, steep streams far away from a lake outlet have a high production of frazil and anchor ice, and consequently a high number of winter floods.

"This type of streams has a more species rich riparian vegetation than streams without frazil and anchor ice production. This is because competitive species of evergreen dwarf shrubs are eliminated by ice and winter floods, and that opens up patches for less competitive species of forbs and grasses", says Lovisa Lind.

The ice formation in the streams also affects the vegetation in the water through scouring and pulling away bryophytes and algae. Ice break-ups during late winter can also have implications for the riparian forest by bending, breaking and pulling away vegetation, thus opening up patches for new species to colonise.

Lovisa Lind has also studied effects of a warming climate on these relationships by, for example, creating experimental flood events.

Meteorologists predict that winter temperatures will vary more, which will lead to more shifts between freezing and thawing. If the mean temperature rises with only a few degrees, this type of ice formation can even be lost. Today, the ice formation in northern systems is already affected by, for example, dams, channelisation, agriculture and pollution.

Since northern Sweden has a large number of small watercourses, extensive areas could potentially be affected by climate change induced shifts in ice dynamics.

"If the disturbance from and winter floods would be lost, the riparian vegetation in northern watercourses could potentially be more dominated by dwarf shrubs. This could have further implications for the fauna and the stream productivity", says Lovisa Lind.


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More information: The thesis is available online: umu.diva-portal.org/smash/reco … 3A785120&dswid=-5050
Provided by Umea University
Citation: Climate change can cause loss of important ice dynamics in streams (2015, February 16) retrieved 24 August 2019 from https://phys.org/news/2015-02-climate-loss-important-ice-dynamics.html
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Feb 16, 2015
Just step outside for a minute, your fears will be put to rest.

Feb 16, 2015
In her thesis, "Results" Really. My thesis for my Online Pubic speaking course, resulted in my earning a PhD in public speaking... You've got to be kidding..

Feb 16, 2015
The ONLY certain thing is that things WILL change. NO scientist can control weather, climate, evolution, human nature and a myriad of other things as well. It is sheer arrogance to even think they CAN, and it borders on tyranny to attempt to tax people into oblivion to support the theories rampant today which claim we CAN control such things.
Please note there is NO "denial" in my post..........just facts which NO scientist can refute.

Feb 16, 2015
The ONLY certain thing is that things WILL change. NO scientist can control weather, climate, evolution, human nature and a myriad of other things as well. It is sheer arrogance to even think they CAN, and it borders on tyranny to attempt to tax people into oblivion to support the theories rampant today which claim we CAN control such things.
Please note there is NO "denial" in my post..........just facts which NO scientist can refute.
How droll. It is the denier's creed - there is no warming because taxes. We can't control what we ourselves are doing because taxes.

There is plenty of denial in your post - what your post lacks are facts.

Feb 16, 2015
Just another point that water is more important than temperature in the AGC.

Just how does anyone believe that every molecule on all the Earth will go up 1 degree C, without everything else that can change, changing?

Science Officer, good point, I remember this weather from 11 years ago, exactly according to the Solar Cycle.

Feb 17, 2015
The ONLY certain thing is that things WILL change. NO scientist can control weather, climate, evolution, human nature and a myriad of other things as well. It is sheer arrogance to even think they CAN, and it borders on tyranny to attempt to tax people into oblivion to support the theories rampant today which claim we CAN control such things.
Please note there is NO "denial" in my post..........just facts which NO scientist can refute.

Sorry there is "denial".
You mention climate, scientists taxes and tyranny all lumped together concerning AGW - that's QED.

Oh, and of course we can "control" weather..... in the sense that not slowing CO2 emission and eventually bringing it to equilibrium - will certainly change weather IN THE FUTURE.
We've fu**ed up the bit for the rest of our lifetimes though, true.

Feb 17, 2015
Question to Water_Prophet
To be clear to everyone observing your evasion first verify u accept terms/definition re vocation as real PC does:-
https://en.wikipe...hemistry
?
This is your very obvious pattern.

When asked direct question re your claimed degree U ignore it & instead make irrelevant claims, u CANNOT answer simple direct questions in your claimed degree - Y ?

It appears u are caught out yet AGAIN !

So, as a claimed Physical Chemist, is your particular training commensurate with the definition in link I supplied above ?

Obviously it SHOULD be as the uni definitions r global but, I will give u a chance to exclude an issue u missed in a lecture or failed to pass in or needed a supplementary due to illness at a main exam.

So tell re Physical Chemistry as per my link above.

R U or R U not educated in this field re a degree with ALL it implies ?

btw: In Oz "graduate level" is studies towards uni degree qualification.

Feb 21, 2015
Parker, Tony Beets and the Hoffman's will all be happy to hear about the loss of ice dynamics in streams, and so am I.

"The polar bears will be fine" - Freeman Dyson

Feb 23, 2015
Elsewhere re the tragedy of Water_Prophet...

Water_Prophet claimed
This means all future increases in atmospheric temperature must have another powerful source. Not CO2!
I wonder what it could be?
I wonder Y someone who claims to be a Physical Chemist (PC) is impotent/clueless as to how to determine quantification of the most appropriate units of Watts per Square meter re CO2 or ANY greenhouse gas ?

As if Water_Prophet completely lied about his claimed degree as a PC ?

Why can't a PC determine energy in Joules by formulating the increase in thermal resistivity of CO2's absorbancy/re-radiation of long wave infra red to Space ?

What seems to be wrong with this Water_Prophet, who makes lots of egotistical claims re his multiple 4 technical degrees yet CANNOT talk like one, articulate fundamentals like one & evades any discussion on issues he cannot find addressed via google ?

Water_Prophet grow up, own up or AT LEAST prove your claimed credentials ?

Caught !

Feb 23, 2015
Headlines I am waiting to see:
FREEMAN DYSON EATEN BY STARVING POLAR BEAR

Mar 21, 2015
Water_Prophet claimed
Just another point that water is more important than temperature in the AGC
What the f..k does this mean, more important re what, specific heat, latent heat, partial pressure, absorbance, what precisely - Y can't u write like the Physical Chemist u claim to be ?

Water_Prophet claimed
Just how does anyone believe that every molecule on all the Earth will go up 1 degree C, without everything else that can change, changing?
What possible dick believes that, not even the religious, where did u hear this crap, do u have more comprehension problems - I have NEVER seen one person ever claim that except YOU !

Water_Prophet claimed
Science Officer, good point, I remember this weather from 11 years ago, exactly according to the Solar Cycle.
But, we know its not as TSI is down, yet contribution re CO2 is up.

Y can't u with claimed "4 technical degrees" not work out CO2's thermal resistivity in W/m^2 ?

Paid, ill or stoopid ?

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