David Tenenbaum: Sand County Irrigation Water

University of Wisconsin-Madison:

More than 14,000 years ago, receding glaciers left a broad, deep swath of sand and gravel across central Wisconsin. Today, the Central Sands region hosts a thriving agricultural economy, but the sandy soil renders most of the crops dependent on irrigation that originates in groundwater.

About 13 years ago, streams, lakes and marshes in the Sands started to dry up, and some observers blamed the growing number of high-capacity irrigation wells. Even though the water level in these fresh waters has improved, the number of high-capacity wells continues to rise, and so the question remains: what is the best route to sustainable irrigation that serves the farm economy and the environment at the same time?

One key question is this: How much water — whether from rain or irrigation — is used by plants, and how much moves deeper, to augment groundwater?...

Already, says Isherwood, the groundwater problem is serious. “The number of high-capacity (irrigation) wells in Portage County just reached 3,000, and there are areas where some lakes are strongly impacted. I’m not one to say that I know what the solution is, but I think farmers need to understand that we have to play a part in this. I think the question becomes, what is my fair share of the aquifer to use?”

John Timmer: How a Rare Butterfly Vanished Then Returned

Are Technica:

Humans, and the invasive species we bring with us, are frequently viewed as destroyers of ecosystems. But we alter them just as often, inadvertently picking winners and losers from among the species as we transform their environment. A paper out in today’s Nature describes a case where our actions made a butterfly species a winner but then changed the game so fast that the local population went extinct. All of this because one man died and his cattle ranch shut down.

"be not too eager to deal out death in the name of Justice ... even the wise cannot see all ends.” Gandalf, Lord of the Rings by J. R. R. Tolkien

One wonders if our in haste to control non-native species at almost all cost that our selection of so-called "good" species might be misplaced and unwise.

 

Vinicius J. Taguchi et al.: Urban Stormwater Phosphorus Dynamics

University of Minnesota:

There is evidence that aging stormwater ponds can become net sources of phosphorus to receiving waters during high flow events. For example, the total phosphorus (TP) concentration in the pond should be equal to or less than the typical inflow TP concentration (due to settling). To evaluate this, we examined data from the Riley Purgatory Bluff Creek Watershed District (RPBCWD) in Minnesota. Between 2010 and 2012, the RPBCWD surveyed 98 ponds and observed high TP concentrations in a number of them...

All of the pond sediments released ortho-P under low DO conditions (< 0.5 mg/L) , as shown in Table 1 and Figure 5). By contrast, ortho-P release was negligible under high DO conditions (not shown). We used the calculated P flux rates for each pond to approximate the potential impact on the overall TP concentration in the pond (Table 1)... Stratification during the summer with turnover and mixing in the fall and spring are normal in large lakes, but small ponds were thought to turn over diurnally or at least during large storm events. Instead, regular manual temperature profiles throughout 2017 revealed evidence of stratification throughout most of the year, with DO concentration below 0.5 mg/L at the bottom sediment surface.

Phosphorus concentration is unusually high in roughly 1/3 of urban stormwater ponds, indicating that they are not performing as designed. Rather than capturing P, these ponds seem to be releasing P and polluting downstream waters. We believe the reason is the sediments are releasing ortho-P to the water column, a process known as internal loading. Phosphorus release from the sediments of ponds may be facilitated by low DO concentration. It appears that many ponds in the Twin Cities Metropolitan Area are stratified through most of the summer by accumulation of road salt in winter and spring snowmelt, therefore leading to low DO concentration that promotes internal loading.

Cody Nelson: The Boundary Waters Future

MPR:

The Boundary Waters may seem unchangeable and stoic. But humankind’s actions over time are far too much for nature. If you know where to look, you can already see the Boundary Waters transforming from a lush forest into a desolate grassland. Warmer temperatures caused by human greenhouse gas emissions are letting maple and oak to start invading the region.

”Later on when the summers get really hot, because it’s shallow rocky soil, most of the trees will die and it will end up being savannah,” said University of Minnesota forest ecologist Lee Frelich. “So grassland with scattered oak trees.” The Boundary Waters’ eventual transition to a savannah, as predicted by research from Frelich and others, is a stunning example of how climate change will affect Minnesota...

Rachel Ehrenberg: What Makes A Tree?

Knowable Magazine:

Thomas Ramsauer/Shutterstock

If one is pressed to describe what makes a tree a tree, long life is right up there with wood and height. While many plants have a predictably limited life span (what scientists call “programmed senescence”), trees don’t, and many persist for centuries. In fact, that trait — indefinite growth — could be science’s tidiest demarcation of treeness, even more than woodiness. Yet it’s only helpful to a point. We think we know what trees are, but they slip through the fingers when we try to define them.

Trees don’t cluster into one clear group: They emerge in multiple lineages and have adopted multiple strategies to become what they are. Take longevity. A classic example of the Methuselah-ness of trees is the current record-holder, a 5,067-year-old great bristlecone pine that grows high in the White Mountains of California. (That tree was almost 500 years old when the first pyramids were built in Egypt.) Scientists speculate that the hardy bristlecones owe their endurance largely to location: They avoid fires that sweep through lower elevations and pests that can’t stomach the harsh terrain of the subalpine zone. The giant sequoias, a short way down the mountains from the bristlecones, take an entirely different longevity tack. These beasts — their trunks can be more than 30 feet across — live thousands of years, fighting fire and pestilence with thick, resistant bark and plentiful in-house repellent compounds.

Some 400 miles to the east, a spindly wisp of a tree has both the bristlecones and the sequoias beat when it comes to lifespan — through another strategy altogether. The quaking aspen (Populus tremuloides) — a tree you can wrap your arms around that rarely grows taller than 50 feet — excels at sending up new shoots from its base. This results in giant stands of “trees” that are, in fact, one genetic individual connected beneath the ground. A Utah colony of quaking aspen is estimated to be 80,000 years old. Neanderthals were around back then.

Speaking of Neanderthals, what makes a human?

Jennifer-Anne Pascoe: The World's Largest High Arctic Lake Changes

Folio:

A 1 C increase in temperature has set off a chain of events disrupting the entire ecology of the world’s largest High Arctic lake. “The amount of glacial meltwater going into the lake has dramatically increased,” said Martin Sharp, a University of Alberta glaciologist who was part of a team of scientists that documented the rapid changes in Lake Hazen on Ellesmere Island over a series of warm summers in the last decade.

“Because it’s glacial meltwater, the amount of fine sediment going into the lake has dramatically increased as well. That in turn affects how much light can get into the water column, which may affect biological productivity in the lake.”

The changes resulted in algal blooms and detrimental changes to the Arctic char fish population, and point to a near certain future of summer ice-free conditions.

Adam Rogers: Our Engineering Made Mississippi River Floods Worse

Wired:

Scientists and anyone who lives within a hundred miles of the winding Mississippi River will tell you—have told you, repeatedly, for 150 years—that efforts to tame the river have only made it more feral. But scientists would like more than intuition, more than a history of 18th-century river level gauges and discharge stations, more than written and folkloric memory. They would like proof...

So climate change causes floods, right? Hah! Too easy. Muñoz’s group ran a statistical model, based on the climate over the entire period of time they now had flood records for, estimating how much more worse flooding should have gotten based on climate change alone. “It comes up with a little bit of an increase, like a 5 percent increase in how big the biggest floods should be,” Muñoz says. “But not all the increase.”

Overall flood risk has gone up 20 percent, the team says. But 75 percent of that risk comes from human engineering of the Mississippi for navigation and flood control.

Bruce Stutz: A City's Green Makeover

Yale Environment 360:

Benjamin Franklin, Philadelphia’s favorite son, described his city’s stormwater problem well: By “covering a ground plot with buildings and pavements, which carry off most of the rain and prevent its soaking into the Earth and renewing and purifying the Springs … the water of wells must gradually grow worse, and in time be unfit for use as I find has happened in all old cities.”

When he wrote this in 1789, many of Philadelphia’s water sources, the scores of streams that ran into the Schuylkill and Delaware rivers, were already cesspools of household and industrial waste. As they became intolerable eyesores and miasmic health hazards, the city simply covered them with brick arches, turned the streams into sewers, and on top constructed new streets, an expanding impervious landscape that left the rains with even fewer places for “soaking into the Earth.” ...

The city is now in the seventh year of a 25-year project designed to fulfill an agreement with the U.S. Environmental Protection Agency (EPA) to reduce by 85 percent Philadelphia’s combined sewer overflows. These overflows occur when heavy rains overwhelm the capacity of the city’s sewage treatment plants to handle the flow from both storm and sanitary sewers, forcing the diversion of untreated effluent into the system’s river outfalls. But rather than spending an estimated $9.6 billion on a “gray” infrastructure program of ever-larger tunnels, the city is investing an estimated $2.4 billion in public funds — to be augmented by large expenditures from the private sector — to create a citywide mosaic of green stormwater infrastructure.

Integrated into the city’s green spaces, streetscapes, and public and private buildings, this green infrastructure ranges from simple home rain barrels and downspout planters to complex bioretention swales underlain by drains, filled with sandy soil, and planted with resilient species of grasses, perennials, shrubs, and trees. Along with rain gardens, tree trenches, green roofs, and urban wetlands, this infrastructure will, as one study put it, “optimize and engineer the landscape” to mimic and restore its natural hydrologic regime. In the end, Philadelphia hopes by the mid-2030s to create the largest green stormwater infrastructure in the United States.

Geoffrey Lean: Death by Lead

The Guardian:

ooking back, it seems insane. Bluntly put, we took a known poison and – for three quarters of a century – used it in machines that puffed it out in breathable form. Then we drove them millions of miles a day, all over the world, regularly dosing billions of people with the toxin...

The study, published in the Lancet Public Health journal and believed to be the first to research the effects of low levels of lead exposure on the general public, also concludes there is no safe level of the toxic metal: people with the lowest detectable amounts were still affected.

Researchers at four North American universities, led by Bruce Lanphear, of Simon Fraser University in Vancouver, studied the fate of 14,289 people whose blood had been tested in an official US survey between 1988 and 1994. Four fifths of them had harboured levels of the toxic metal below what has, hitherto, been thought safe.

The study found that deaths, especially from cardiovascular disease, increased markedly with exposure, even at the lowest levels. It concluded that lead kills 412,000 people a year – accounting for 18% of all US mortality, not much less than the 483,000 who perish as a result of smoking.

Nathan Rott: Decline of Hunting Threatens Conservation

NPR:

A new survey by the U.S. Fish and Wildlife Service shows that today, only about 5 percent of Americans, 16 years old and older, actually hunt. That’s half of what it was 50 years ago and the decline is expected to accelerate over the next decade. Meanwhile other wildlife-centered activities, like birdwatching, hiking and photography, are rapidly growing, as American society and attitudes towards wildlife change. The shift is being welcomed by some who morally oppose the sport, but it’s also leading to a crisis.

State wildlife agencies and the country’s wildlife conservation system are heavily dependent on sportsmen for funding. Money generated from license fees and excise taxes on guns, ammunition and angling equipment provide about 60 percent of the funding for state wildlife agencies, which manage most of the wildlife in the U.S.

This user-play, user-pay funding system for wildlife conservation has been lauded and emulated around the world. It has been incredibly successful at restoring the populations of North American game animals, some of which were once hunted nearly to extinction. But with the slide in hunting participation expected to speed up in the next 10 years, widening funding shortfalls that already exist, there’s a growing sense of urgency in the wildlife conservation community to broaden that funding base.

Adam Hinterthuer: The Life of Steve Carpenter

UW-Madison Center for Limnology

It’s been nearly six months since Steve Carpenter officially stepped down as director of the UW–Madison Center for Limnology. Yet, despite updating his resume with the title “free-range scientist,” he is still trying to figure out how to not come in to the office. “One thing I’m working on is how to retire, which I have so far completely failed at,” says Carpenter, the Stephen Alfred Forbes Professor of Integrative Biology (formerly Zoology).

Case in point: He never did go bow hunting this season. Even though he bought his first bow and found enough time to practice to get comfortable from 50 yards, he didn’t put it to much use. “Some of it was rain, but why couldn’t I make more time? It wasn’t always rain,” he laments. The problem is there’s still so much science to do.

For example, Carpenter recently attended an event on the “roots of creativity and innovation in science” at the National Academy of Sciences (NAS) campus in Irvine, California. It was an invitation-only affair for NAS members like him and a select group of actors, poets, writers and filmmakers.

As with so much else in life, Carpenter found this combination of art and science too exciting to refuse. He has a hard time saying “no” to new ideas and collaborations, which probably helps explain his impressive career.

A gifted scientist that has greatly increased our understanding of lakes.

Nina Leopold Bradley: Sense of Place

The Aldo Leopold Foundation (previously published in The Leopold Outlook)

Today I speak to you of my own experience, my own deep attachment to a particular place. This attachment happened over time, with my family, on a sand farm along the Wisconsin River – land that was neither grand nor dramatic, but mundane, humbled, and degraded. It seems to have happened by slow accrual, like the growth of a coral reef. I dwell in this place and am finally apart of this place...

On our sand farm along the Wisconsin River, I was able to get inside the scenery and the landscape. I became a living part of a living place. As we worked with family, friends, and neighbors, to restore health to the abused land, we were experiencing the slow sensitizing of people to land. We learned how to look, how to dwell and how to think about land. This was sick land but rich country for the growth of perception.

No one knew better than my father, Aldo Leopold, the joy of wild, unspoiled land. His love of wilderness was passionate and enduring. He had spent immense energy in protecting wilderness and trying to understand its dramatic complexity. He realized that wilderness was important in part so that we might retain the capacity to compare unspoiled land with lands more intensively altered by human economic activity. Leopold’s rationale for wilderness protection was not just recreational or scenic, but scientific, biological, political, economic and deeply aesthetic.

Cody Nelson: Shorter Winters and Algal Populations

NPR:

A team led by University of Minnesota-Duluth researchers, that was the point: They want to know how shortening winters — and less ice cover on lakes — may increase the presence of harmful algae blooms and impact the fishery. Aside from people who ice fish, the general assumption is that not much happens in lakes during winter, said Andy Bramburger, a research associate from the U’s Duluth campus.

The biggest effect of climate change on lakes isn’t necessarily how warm it gets, but how cold it doesn’t get. These warmer winters are shorter, so more sunlight can reach the water earlier, jumpstarting algae production and affecting the lake’s biology.

Bill Lindeke: Minnesota's Capitol versus Wisconsin's

streetsMN:

It’s time once again for the Minnesota legislative session, the annual period of time when laws are debated at length, stall out completely, and then get decided at the very last minute with no prior knowledge of what’s in them. For those who are into politics, it’s a fun time.

But I want to take today and discuss an open secret about the Minnesota state capitol located in Saint Paul, Minnesota: it’s terrible urbanism...

I always contrast the lifeless Minnesota State Capitol in my mind with the amazing example of the Wisconsin State Capitol in Madison. Both buildings are beautiful, but the key difference is that the Wisconsin building is surrounded by vibrant urbanism. It is in every way the gold standard for how a state capitol and its surrounding government buildings can fit seamlessly into a walkable city.

Sophie Yeo: Resilience to Climate Change

Pacific Standard:

Kodiak Island Borough is a remote community of around 14,000 people that spreads down the coast of the Alaska Peninsula and across 16 islands. It sits downwind from a cluster of active volcanoes, and its six villages are accessible only by boat or plane. It is home to 3,500 oversized bears.

It is also one of the safest places to live in the United States—at least when it comes to climate change. A recent survey of America’s 3,135 counties concluded that this inhospitable stretch of land is the most climate-resilient place in the entire nation...

The results shed light on the vast inequalities in how different parts of the U.S. will deal with such hazards. While places like Kodiak Island are expected to fare well, residents of areas like Appalachia, the southeast, and western Texas are on course to suffer far worse than the average American.

Jeff Gillies: Lake Superior's Big Wave

Environmental Monitor:

A pair of lonesome data buoys bobbing off Michigan’s storm-whipped Lake Superior shore were suddenly the stars of the state this fall when they captured the largest waves ever measured on the Great Lakes.

The buoys, near Granite Island and Munising, each recorded 28.8-foot significant wave heights during a storm that caused hundreds of thousands of dollars of damage along the coast. The record wave height exceeded the previous 27.6-foot record set by a Michigan Tech buoy near Houghton, Mich., in 2012. To give some perspective on the rarity of these types of events, waves at the record-capturing buoys only climbed above 12 feet four times throughout 2015 and 2016.

Laurel Wamsley: Free Transit Considered for Germans

NPR:

Germany is considering free public transit in its cities in order to curb car use, as it hurries to meet the European Union’s requirements for air quality. That proposal is put forth in a letter to from the German government to the EU’s Environment Commissioner. The free transit plan is part of a range of measures suggested in the letter, including low emission zones, incentives for electric cars, and technically retrofitting existing vehicles, Reuters reports.

”We are considering public transport free of charge in order to reduce the number of private cars,” the letter says, according to Agence France Presse. “Effectively fighting air pollution without any further unnecessary delays is of the highest priority for Germany.”

Cheryl Dybas: Large Rains Mean High Phosphorus Pollution

National Science Foundation:

While April showers might bring May flowers, they also contribute to toxic algae blooms, dead zones and declining water quality in U.S. lakes, reservoirs and coastal waters, a new study shows. In the Midwest, the problem is largely due to phosphorus, a key element in fertilizers that is carried off the land and into the water, where it grows algae as easily as it grows corn and soybeans.

Previous research had found that waterways receive most of their annual phosphorus load in only a dozen or two events each year, reports Steve Carpenter, director emeritus of the University of Wisconsin-Madison’s Center for Limnology and lead author of a new paper published online in the journal Limnology and Oceanography. The paper ties those phosphorus pulses to extreme rain events. In fact, Carpenter says, the bigger the rainstorm, the more phosphorus is flushed downstream.

Linda Poon: Fox and Coyote Interactions in City

The Atlantic

In the wild and in the countryside, coyotes are not only bigger than red foxes, but they’re also higher up the food chain. They tend to push weaker competitors out of their territories and will even kill to protect access to limited food sources. So while red foxes exist in the same general area and may even establish homes at the periphery of where coyotes live, they rarely venture into the other predators’ domain.

In cities, though, it looks like they’re learning how to get along. That’s according to Drake’s latest study published in the journal PLOS One. Over the years, foxes and coyotes, like so many other wild species, have settled in the city, and they’re inevitably here to stay. Some animal species have adapted to thrive amid the human-dominated landscape of high-rises, fragmented green space, and heavy traffic. Now, at least in the case of these two wildlife predators, they may be changing their behavioral instincts to coexist with each other—thanks in part to the abundance of food.

Jacques Leslie: Self-Driving Cars - Utopia or Dystopia?

Yale360:

Automated cars, often referred to as “autonomous vehicles” (AVs) — whose passengers determine their routes without having to drive them — are being widely developed and tested, and probably will be used commercially in controlled settings within a few years. Lyft, Uber, and others have introduced ride-sharing, in which customers agree to travel with strangers in return for reduced fares. Put all three concepts together in one vehicle, posit that within a few decades this shared EV-AV technology will take over the nation’s automobile fleet, and the outcome seems environmentally irresistible, verging on fantastical.

But it’s equally plausible that the vision may turn out to be a mirage. Automated vehicles may eventually be widely adopted, but if the fleet is not electrified using renewable energy, or car sharing fails to take off, greenhouse gas emissions and air pollution could actually increase. A study last year by University of California, Davis researchers projected that if vehicles are automated but not electrified or shared, greenhouse gas emissions from the transportation sector would go up 50 percent by 2050 compared to business as usual. But if shared, electrified, automated vehicles flourish, greenhouse gas emissions could plunge by 80 percent, the study concluded⁠.