Barbara Heitkamp: Minnesota's Vanishing Shorelines→

knickpoints:

“The most noticeable projects for the boat tour participants were the scattered pops of color along the shoreline where several residents have worked with the SWCD and LID to install native plant shoreline buffers. These buffers provide multiple benefits to both the homeowner and the lake, with one of the largest benefits being that buffers help slow and infiltrate stormwater runoff that carries pollutants into the lakes – much more effectively than traditional turf grass. Plus, the long roots of the native plants hold the shoreline in place, preventing shore erosion while also providing habitat for pollinators and other wildlife.

Still, as I sat there in the boat, the number of properties with shoreline buffers were greatly outnumbered by those with no buffers, riprapped shores, extensive gravel beaches, or lawn down to the shore. It made me think of a recent paper that was published by the Minnesota Natural Shoreline Partnership that speaks to Minnesota’s “Vanishing Shorelines.” In effect, how we live along our shorelines has a direct impact to the health and vitality of the lake and its ecosystems. While individual shoreline property owners may not think their actions can influence water quality and aquatic life, the cumulative impact of a majority of neighbors developing these shorelines and removing vegetation and/or rocking the shore has an extensive impact.”

Bob Berwyn: Large Lakes in Peril →

Ars Technica:

“Water storage in many of the world’s biggest lakes has declined sharply in the last 30 years, according to a new study, with a cumulative drop of about 21.5 gigatons per year, an amount equal to the annual water consumption of the United States.

The loss of water in natural lakes can “largely be attributed to climate warming,” a team of scientists said as they published research today in Science that analyzed satellite data from 1,980 lakes and reservoirs between 1992 and 2020. When they combined the satellite images with climate data and hydrological models, they found “significant storage declines” in more than half of the bodies of water.

The combination of information from different sources also enabled the scientists to determine if the declines are related to climate factors, like increased evaporation and reduced river flows, or other impacts, including water diversions for agriculture or cities. A quarter of the world’s population lives in basins where lakes are drying up, they warned.”

University of Bristol: Underwater Sounds of Ponds→

PHYS.ORG:

Old Sneed Park; credit: Dr Jack Greenhalgh

““Ponds are packed full of bizarre and mysterious sounds made by scratching aquatic insects, booming fish, and popping plants. It’s like an underwater disco,” explained lead author Dr. Jack Greenhalgh from Bristol’s School of Biological Sciences.

To better understand these mysterious soundscapes, the team collected 840 hours of underwater sound recordings from five ponds in the southwest of England using an underwater microphone (a hydrophone). In findings published in the journal Freshwater Biology, analysis of the audio files revealed clear daily acoustic activity cycles in each pond.

Typically, a nocturnal chorus is made by aquatic insects that compete to attract mates by producing strange scratching sounds as they rub their genitals against their abdomens. During the daytime, however, aquatic plants dominate the underwater orchestra with rhythmic whining and ticking sounds produced as tiny oxygen bubbles are released by plants respiring in the hot sun.”

Helmholtz Association of German Research Centres: Shallow Lakes→

Phys.org

“In a data analysis of 902 shallow lakes, the research team found no evidence for the existence of two alternative stable states. The authors are critical of lake management measures based on this theory. They recommend that greater emphasis be placed on the reduction of nutrient inputs in the future to ensure the ecological equilibrium of shallow lakes...

But what do these results mean in practice? How can we maintain the ecological equilibrium of shallow lakes? “Biomanipulative measures such as adding piscivorous fish cannot stabilize the shallow lake ecosystem in the long term, because there is no alternative stable state,” says Graeber. “There is only one way to maintain the equilibrium of shallow lakes in a continuous stable state, and there’s no alternative: Nutrient inputs have to be consistently reduced.”

”

Jeff Renaud: Predicting Fish Recovery from Mercury Pollution

University of Western Ontario:

“Reducing mercury pollution entering lakes lowers how much harmful mercury is found in freshwater fish destined for consumers’ plates. This is according to a new paper, published today in Nature. During the study, conducted over 15 years, scientists intentionally added a traceable form of mercury to an experimental lake and its watershed.

The interdisciplinary research team, including Western University’s Brian Branfireun, discovered that the new mercury they added quickly built up in fish populations, and then declined almost as quickly once they stopped additions.

Notably, the fish populations were able to recover from mercury much quicker than previously understood, which suggests that curbing mercury pollution through policy initiatives now will have a rapid and tangible benefit on the quality of fish we consume.”

More information: Paul Blanchfield, Experimental evidence for recovery of mercury-contaminated fish populations, Nature (2021). DOI: 10.1038/s41586-021-04222-7. www.nature.com/articles/s41586-021-04222-7

Northern Lakes Warming 6x faster

York University:

“Lakes in the Northern Hemisphere are warming six times faster since 1992 than any other time period in the last 100 years, research led by York University has found.

Lake Superior, the most northern of the Great Lakes which straddles the Canada/United States border, is one of the fastest warming lakes, losing more than two months of ice cover since ice conditions started being recorded in 1857. In Lake Suwa, in Japan, ice formed close to 26 days later per century since 1897 and is now only freezing twice every decade, while Grand Traverse Bay in Lake Michigan had one of the fastest ice-off trends, melting about 16 days earlier per century.

”We found that lakes are losing on average 17 days of ice cover per century. Alarmingly, what we found is that warming in the past 25 years, from 1992 to 2016, was six times faster than any other period in the last 100 years,” says Associate Professor Sapna Sharma of the Faculty of Science at York University, who led the study with Professor David Richardson at the State University of New York at New Paltz and climate scientist Iestyn Woolway, Ph.D., of the European Space Agency Climate Office, United Kingdom.”

More information: Sapna Sharma et al, Loss of Ice Cover, Shifting Phenology, and More Extreme Events in Northern Hemisphere Lakes, Journal of Geophysical Research: Biogeosciences (2021). DOI: 10.1029/2021JG006348

York University: Northern lakes at risk of losing ice cover→

Phys.org:

Alessandro Filazzola

“Close to 5,700 lakes in the Northern Hemisphere may permanently lose ice cover this century, 179 of them in the next decade, at current greenhouse gas emissions, despite a possible polar vortex this year, researchers at York University have found.

Those lakes include large bays in some of the deepest of the Great Lakes, such as Lake Superior and Lake Michigan, which could permanently become ice free by 2055 if nothing is done to curb greenhouse gas emissions or by 2085 with moderate changes.”

Will Cushman: The Health of Lakes→

WisContext:

“The destruction of shoreline and near-shore habitat can also take a toll on aquatic life, Sorge said. This process is often instigated by development of buildings and other shoreline structures, which often transforms biodiverse native habitats into species deserts.

Shoreline development also increases runoff into lakes, Sorge added. “Once we get to even as little as 15% of [a lakeshore] lot covered with rooftops, sidewalks, walkways, driveways, you’ve increased the mass loading of phosphorus from that parcel of land by a factor of six,” he said. “Our lakes cannot sustain these types of increased inputs if we don’t manage them.””

Please watch the video of Buzz Sorge’s presentation!

Greg Stanley: Ice and Walleyes Signal Changing Climate→

Star Tribune:

“Across Minnesota, lakes are losing up to four days of ice every 10 years, according to the state climatology office. And it’s not just Minnesota: Rivers and lakes across the continent are tending to freeze later and thaw earlier. “You think of all the ways people interact with lake ice — skating, fishing derbies, iceboats,” said John Magnuson, an ecologist and limnologist at the University of Wisconsin, Madison. “And already, in some of these lakes you have about a month less to do it.”

... at the University of Wisconsin, the first school in the country to study the chemistry and makeup of inland lakes, scientists have been keeping that data for decades. The university has tracked ice coverage on Wisconsin lakes since the 1850s. In those days, ice harvesters needed to know when they could venture out on a lake to cut large frozen blocks to sell during summer; parents and school superintendents waited for ice roads that would connect Lake Superior’s Apostle Islands to the mainland.

The longer the data go back, the clearer the pattern becomes: Lakes have less ice now, said Magnuson, who is semiretired after decades with the school’s limnology office. Lake Mendota in Madison gets 30 days less ice coverage — a full month — than it did during the Civil War, the data show. And the thaws have been accelerating, Magnuson said. Six of Lake Mendota’s 10 earliest ice-outs have happened since the late 1990s.

Ice coverage is not just a function of temperatures in the spring and fall. It reflects two larger factors: the area’s average annual temperature and the depth of the lake. Every body of water is continually heating up through the summer. The deeper the lake, the more volume it has to collect and store that heat. The more warmth a lake stores, the longer it takes to freeze, Magnuson said.

For the first time, some of the deepest lakes in southern Wisconsin are starting to have years when they don’t freeze at all. As temperatures continue to climb, that will happen to more and more lakes in Minnesota as well, Magnuson said. The magic number seems to be about 47 degrees Fahrenheit. Once the average temperature for an entire year reaches that point, lakes that have historically frozen over every year start to see some years where they remain open.”

Alan Guebert: Corporations Have Rights; Why Not a Lake?→

Farm & Food File:

“If the ballot box is the ultimate source of power in the United States, then voters in Toledo, Ohio, used that power Feb. 26 to create what’s now being called a “Bill of Rights” for their wide, blue neighbor, Lake Erie. That vote, if it withstands court challenges (one was filed immediately after the referendum passed) gives any Toledo citizen legal standing to sue any person or corporation on behalf of Lake Erie over its “right” to be clean and environmentally healthy.

Lake Erie’s newly conferred/newly challenged rights have farmers in northwest Ohio deeply concerned because they have long been seen as a key source of the phosphorus run-off that fuels late-summer, toxic algae blooms in the lake, that also serves as Toledo’s public water source. But it’s not just Toledo. The toxic blooms, according to press reports, threaten the water supply of 12 million American and Canadian citizens living near Lake Erie and jeopardize more than $1 billion a year spent in Ohio on lake tourism.”

Nadja Popovich: Lake Ice Future→

New York Times:

“In a study published last week in the journal Nature Climate Change, scientists for the first time quantified the effects of rising temperatures on ice cover across 1.4 million lakes in the Northern Hemisphere. They found that, from Wisconsin to Japan, thousands of lakes that used to freeze reliably every winter already see some years without ice, and that “an extensive loss of lake ice will occur within the next generation.”

The vanishing ice will affect cold-water ecosystems and be felt by millions of people who live near northern lakes, the study said.”

The study.

Brad Dokken: Vehicle at Bottom of Lake?→

Brainerd Dispatch:

“Thompson, who aptly is nicknamed “Seal,” says Tri-State Diving does anywhere from 10 to 15 salvage operations in a typical winter. As of mid-January, the company already had pulled nine ATVs, vehicles or fish houses from lakes across the region, and more jobs await them when weather conditions improve. “It’s getting to be more and more because of how well we’re getting known and insurance companies calling us direct,” Thompson said. “‘Dirty Jobs’ put us on the map.”

Tri-State shoots photos or video of all of its retrieval jobs and posts the footage on Facebook, Thompson said, which also helps to spread the word. “Plus, there are a lot of the areas where conservation officers know the kind of work we do, and they refer (people) to us,” he said.

Tri-State uses a device called a SUVE (pronounced soo-vee)—which stands for Submerged Underwater Vehicle Extractor—for retrieving vehicles. In very basic terms, the SUVE is like a big teeter totter with a winch on the top to raise whatever’s submerged to the surface. Thompson has patents on both the apparatus and the teeter-totter concept it employs, he says. “It’s just two rails (the vehicle) rides up, and once it’s up on top and gets past center, we just bring it down on the ice,” Thompson said.”

David Peterson: Lake Water Level Appeal→

Star Tribune:

“The state of Minnesota will appeal a landmark ruling on the excessive pumping of groundwater around White Bear Lake, saying it is “not supported by scientific evidence” and would “immediately halt important development” within five miles of the lake.

In a written statement Tuesday underlining the ruling’s potential to reach all across Minnesota, DNR Commissioner Tom Landwehr said: “The DNR is strongly committed to protecting Minnesota’s many precious water resources, including White Bear Lake and its surrounding aquifers. We take that responsibility very seriously. But responsible, effective water management must be supported by sound science.”

Katie Crosby Lehmann, lead attorney in a team of lawyers that worked the case over several years’ time, said in a statement late Tuesday: “We stand by the detailed scientific evidence from the monthlong trial. As demonstrated by the [judge’s 140-page] opinion, the DNR has known of the problems caused by its permitting actions since issuing its own 1998 study and has concluded that the water use in the north and east metro area is not sustainable.””

Also see Pioneer Press's article.

Steven Verburg: Farm Pollution Exacerbated by Zebra Mussels→

Wisconsin State Journal:

“An explosion of the zebra mussel population in Lake Mendota this year could mean more foul-smelling shoreline slime and repeats of the major fish kill and vast bloom of toxic bacteria that hit Madison’s lakes already this summer, experts say.

Farm pollution is the main driver of this month’s surprisingly severe water quality woes, but the invasive mollusks now covering much of Lake Mendota’s bottom aren’t going to help matters.

“We’ve been shocked to see how many there are,” said Jake Vander Zanden, UW-Madison’s top expert on zebra mussels.

Zebra mussels change a lake by filtering food from water, which makes water clearer so that additional sunlight reaches the bottom. The sunlight, along with nutrients mussels excrete on the bottom, spur plant growth and the potential for more dead vegetation washing up and decomposing in smelly piles on shores, Vander Zanden said.

This year divers are finding a typical zebra mussel by-product — bottom-clinging mats of algae that look like green cotton candy — all over Lake Mendota, he said.”

Greg Seitz: Earth's Lakes→

MinnPost:

“Minnesota has about five percent of America’s lakewater right here, with a total volume of 66 cubic miles (not counting Lake Superior). That’s about twice as much as a typical state.

Our state’s most famous lake is surely Superior, the biggest freshwater lake in the world by surface area and, as it turns out, the largest volume of lakewater in the United States, and six percent of all the lake water in the world.

It’s so big that if you poured all the inland lakes in America into it, Superior wouldn’t even be half full. Its 2,900 cubic miles of water is more than in the other four Great Lakes combined, which contain another five percent of the world’s total lake water. They are truly great, and superior.”

Lee Bergquist: Water Wars on the Sand Counties of Wisconsin→

Milwaukee Journal Sentinel: Two articles on groundwater and lakes

“War Over Water

In 2010, Minnesota lawmakers passed legislation giving that state’s DNR the authority to establish groundwater protection areas that allow the agency to limit water use to meet human needs and protect lakes, streams and wetlands.

After three years of review, the first protection area was designated in November 2015 in metropolitan St. Paul — an area that runs to the Wisconsin border. Two other areas have been identified in rural areas of Minnesota.

In Wisconsin, with Kraft’s work being questioned and environmentalists pressing for action, the DNR and the growers association underwrote a two-year, $230,000 study of the Little Plover.

In April, the Wisconsin Geological & Natural History Survey and the U.S. Geological Survey found that groundwater played a key role in the health of the Little Plover; the river was vulnerable to groundwater pumping; and that stream flows would improve substantially if wells nearest the river were removed.

The study “did not refute the work of Dr. Kraft — if anything, it built on that work,” said Ken Bradbury, director of the state natural history survey and co-author of the study.

But Tamas Houlihan, executive director of the potato and vegetable group, said his industry isn’t convinced, although he says growers near the Little Plover have voluntarily changed their farming and irrigation practices to conserve water.”

— http://www.jsonline.com/story/news/local/wisconsin/2016/09/03/war-over-water-land-plenty/89481060/

“Water Policy

Plainfield — Three years after Brian Wolf bought his home on Long Lake in 2006, lawmakers and water policy experts began stopping by to see what had happened to the lake.

”It’s as if someone pulled the plug in a bathtub,” Wolf told one group of visitors in November 2009. “This lake is dead.”

Legislators left Wolf’s home in western Waushara County with plans to address growing worries about high-capacity wells and the effect groundwater pumping was having on lakes, rivers, streams and wetlands.

But lawmakers tried and failed to pass a groundwater bill in the 2010 legislative session. This year, legislative efforts also went nowhere.

This summer, the water in Long Lake is mostly gone, dotted by a few marshy areas. Cattails and grasses sprout from the former lake bed. Other traditionally shallow lakes in this region of sandy soil in the middle of the state have shared similar fates.

A dock on Long Lake near Coloma is surrounded by weeds. The lake has seen its water levels plummet and has become a marsh. Landowners blame the large number of high-capacity wells used to irrigate crops in the region.

They have become symbols of the tug-of-war over water use in Wisconsin. The advantage has shifted to large water users as the number of high-capacity wells have proliferated and efforts to put more limits on the use of groundwater have foundered.”

— http://www.jsonline.com/story/news/local/wisconsin/2016/09/04/conflicts-thwart-reforms-state-water-policy/89482796/

Jake Vander Zanden: Lake Dead Zones→

Reporting from New Zealand:

“UW-Madison’s Limnology Center: Earlier this year, Jake Vander Zanden rented his house out in Madison, packed his things, and headed with his family for a sabbatical in New Zealand. Under the auspices of a Fulbright scholarship, Jake is at the University of Waikato, studying ‘dead zones’ in lakes, where pollution reduces oxygen making it impossible for parts of lakes to support life.

Tell us about your research here in New Zealand
I’m looking at the phenomenon of lake ‘dead zones’. Lakes that in the past had a lot of oxygen in the bottom waters can lose that oxygen due to nutrient pollution – often from human activity – then they become an environment that can’t support life. You lose a lot of the value that would come from a lake, such as fisheries, when you have dead zones.

It seems like once you create dead zones they are difficult to turn back. Even if you remove nutrients and improve conditions, the healthy ecosystem never returns. That’s really worrisome because it is so difficult to fix the problem. Another consideration is that when you create a dead zone, the plant nutrient phosphorus is released from the lake sediments, which further contributes to the pollution problem.”

Thompson and Rogers: Global Warming Threatens Lake Trout→

Thunder Bay News:

“Warming water from climate change is beginning to encroach on the habitat of Northwestern Ontario’s cold water fish. Research conducted at the Experimental Lakes Area shows the region’s temperature has warmed 0.4 C over each of the last five decades. Shorter winters are heating surface water and delaying lake trout spawning.

The runoff from increasing summer rain is causing a tea-like discolouration, affecting the water’s heat distribution and compounding the change. Added together, fish biologist Lee Hrenchuk can see consequences for aquatic ecosystems beginning to show.

“The average size of an adult fish has been decreasing over time and we’re seeing this mostly in the cold water fish species that are really dependent on having good spring periods and good fall periods where they can do a lot of eating,” Hrenchuk said.”

Jim Erickson: Voluntary Actions May Not Solve Lake Erie's Pollution Problem→

University of Michigan:

“Large-scale changes to agricultural practices will be required to meet the goal of reducing levels of algae-promoting phosphorus in Lake Erie by 40 percent, a new University of Michigan-led, multi-institution computer modeling study concludes.

The main driver of the harmful algal blooms is elevated phosphorus from watersheds draining to Lake Erie’s western basin, particularly from the heavily agricultural Maumee River watershed. About 85 percent of the phosphorus entering Lake Erie from the Maumee River comes from farm fertilizers and manure.

The new study, which integrates results from six modeling teams, was released today by the U-M Water Center. It concludes that meeting the 40-percent reduction target will require widespread use of strong fertilizer-management practices, significant conversion of cropland to grassland and more targeted conservation efforts.

”Our results suggest that for most of the scenarios we tested, it will not be possible to achieve the new target nutrient loads without very significant, large-scale implementation of these agricultural practices,” said U-M aquatic ecologist Don Scavia, lead author of the new study and director of the Graham Sustainability Institute.”

You can ask farmers to help, you can pay farmers to help, you can tell farmers to help, or is there another way? 

Ross Andersen: Insight from Lake Sediment→

Atlantic:

“On a spring morning in New Hampshire, 2,000 years ago, sunlight struck a black cherry tree, opening its white-and-yellow blossoms. As the tree swayed gently in breeze, spiky, spherical pollen grains spilled out of its flowers, and floated up through the limbs and leaves of the canopy, before drifting down to the still surface of a nearby lake. Cool water stalled the pollen’s descent, but still, it kept falling, riding the currents all the way to the lake’s bottom, where it mixed with silt and slowly hardened into sediment.

Time piled new layers of mud and soil atop the pollen, pushing it deeper into the Earth. For two millennia, it continued to sink at that geologic pace, until suddenly, and with some violence, it was slurped up to the surface, through an aluminum tube.

Sitting on a floating platform, a small team of scientists pulled the pollen up as part of a cylinder of sediment, a core bored out of the lake bottom. A core looks like nothing more than a cross-section of muck, but each of its sedimentary slices is an archive, packed with fragments of sticks and leaves, charred remains of wood—and enough pollen grains to census the trees that once surrounded the lake.”