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Trees Filter Pollution, Reduce Algae Blooms

Tree-hating mayoral candidate Travis Schaunaman would make Aberdeen not only bleaker but stinkier. According to scientists at the University of Minnesota, those trees Travis blames for standing in the way of capitalism help reduce algae blooms caused by some of our commercial fertilizers:

Every city needs its trees. They reduce air pollution. They cut down on wind. They absorb and store carbon in their massive trunks. In summer, their canopies provide welcoming shade, cooling the grounds and houses underneath, which saves energy and money on air conditioning. But it turns out that trees can perform yet another service essential for humans. They can also help reduce soil pollution caused by nutrients leaching into the grounds from commercial fertilizers used in agriculture, gardening, and lawn care.

…This over-fertilization causes the infamous algae blooms, which decrease water oxygen levels and smother aquatic life. Many urban waterways suffer from over-fertilization by the excess nitrogen and phosphorus. In the summer, these waterways turn green, filling the air with an unpleasant stink.

I think that I shall never see As wise an investment as a tree....
I think that I shall never see
As wise an investment as a tree….

…trees—and particularly deciduous species—did a good job of eliminating phosphorus from the ground. “Trees reduced P [Phosphorus] leaching compared with turfgrass in both 2012 and 2013, with lower leaching under deciduous than evergreen trees,” the team wrote in the study. Moreover, compared to industrial solutions for phosphorus cleanup, trees also proved to be a cost-efficient option. When the team applied their measurements to the Mississippi River’s urban watershed, which includes about 1.5 million trees, they found that the trees helped achieve significant infrastructure savings. In 2012, the forested grounds prevented half a ton of phosphorus from spilling into the water, and the next year that amount more than doubled. That saved several million dollars in infrastructure costs. “Removing these same amounts of P [Phosphorus] using stormwater infrastructure would cost $2.2 million and $5.0 million per year (2012 and 2013 removal amounts, respectively),” the authors wrote [Lina Zeldovich, “How Trees Can Save Lakes from Algae Blooms,” JSTOR Daily, 2019.05.14].

Look at that: requiring commercial property owners to plant more trees helps get rid of the pollution caused by commercial activity and helps government spend less money. Gee, isn’t less government what so-called conservatives like Travis Schaunaman and his partisan supporters say they want?

Folks living along slow-moving, sometimes strong-smelling Moccasin Creek should all vote for Mayor Mike Levsen… and plant a tree for each vote.

7 Comments

  1. From the link above: “The results of our study suggest that reduction of anthropogenic sources of NOx, VOCs, and PM, for example, reduction of the motorized vehicle fleet, would have to accompany urban tree planting campaigns to make them really beneficial for urban dwellers.”

    From Popular Science discussing the Berlin study:

    To be clear, this is still entirely our fault. On their own, the trees’ VOCs don’t pose a threat. But once in the air, they undergo a chemical reaction with Nitrogen Oxides (NOx) —a byproduct of burning fuel, like the gas that power our cars’ engines—that adds more ozone to the mix. NOx causes a host of negative health effects ranging from respiratory issues to heart attacks. At the same time, ground level ozone irritates respiratory systems, aggravates asthma and chronic lung disease, and can even cause permanent lung damage.

    …This doesn’t mean that we should stop planting trees, since ultimately, it’s the underlying human-produced pollution that’s the problem. Plus, the study only suggests that trees boost our pollutants during heatwaves, not all the time. And even the increased temperatures of the heatwave that Churkina studied can be blamed on, well, us. A 2015 study found that the 2003 European heatwave was caused mainly by climate change.

    But the study makes it clear that it isn’t enough for us to plant trees—we have to lower pollution as well [Kendra Pierre-Louis, “Trees Might Actually Make Summer Air Pollution Even Worse,” Popular Science, 2017.05.17].

    Trees provide all sorts of other benefits during heat waves and during milder weather. Trees only cause the VOC increase if we keep irresponsibly burning and polluting.

    And trees still reduce algae blooms, making heat waves less stinky.

  2. TAG

    Cory, you provided a nice laundry-list of tree benefits. Another one you didn’t mention is how well trees control storm-water runoff rates. They are hugely influential in:
    Trapping and evaporating rain that collects in the canopy
    slowing runoff velocity rates as the rain filters through the canopy
    increasing the permeability and aeration of soil with roots and leaf litter accumulation
    reducing soil erosion with roots.

    All of these functions are critical in cities, with our expanses of impermeable roofs, roads and parking, and highly compacted soils, that speed storm-water and pollutants into the storm sewer and streams. Not only are trees good for limiting pollution, but they can help reduce the sizing of very expensive stormwater infrastructure for the city and developers. Engineers include tree-cover in stormwater calculations.

  3. jerry

    Snow fences and shelter belts as well. The next solution to air pollution from auto’s is this a graphene sponge, wow!

    “Researchers at Chalmers University of Technology in Sweden claim to have made a breakthrough in the development of lithium sulphur batteries, offering a fivefold increase in energy density over today’s lithium-ion, using a graphene sponge.

    Graphene, a honeycomb lattice of carbon measuring just one atom thick, has been positioned as a miracle material for a range of technologies – including batteries, where it has been available on the market since 2012. Researchers at Chalmers University of Technology, though, have now found a way to use a graphene sponge to help bring energy-dense lithium sulphur batteries to market – potentially boosting the lifespan of future mobile devices fivefold.

    Where a traditional battery is made up of four key parts – the anode, cathode, electrolyte, and a separator so the anode and cathode electrodes don’t make direct contact – the researchers’ work sees the cathode and electrolyte combined into a single liquid dubbed a ‘catholyte’. Previously, though, this combination – while offering reduced weight, faster charging, and improved capacities – proved unreliable.” https://bit-tech.net/news/tech/researchers-mix-graphene-and-sulphur-for-battery-breakthrough/1/

  4. Porter Lansing

    Excellent post, Jerry. #HandClaps

  5. Good point about filtration of storm runoff. I’ve heard the Schaunaman camp complain that one tree in a parking lot won’t do much and that one tree buried by the snow plows every winter will probably not survive to do much good. That sounds to me like a justification for upping the tree requirement: instead of having one isolated tree on a tiny curbed-in patch, require a regular shelterbelt with a wide expanse of turf to separate the trees from most of the snow dumpage from the plows. More roots, more filtration, more protection from the wind, more algae protection… and more shady parking spots, meaning more happy customers lingering inside and buying more stuff (thus increasing consumption, production, waste, greenhouse gases… dang!).

  6. Porter Lansing

    It’s hard to wrap my brain around this story, truthfully. I GOOGLED “Are there anti-tree politicians?” No hits. Nada. Schaunaman has truly found a piece of politics no one has ever dared to enter. I’d wager that less than half of Americans are anti tree. #satire It’s like being anti-mother. I know. It’s about the group telling individuals what to do. That’s group politics, Schaunaman. Sheesh!! We beat the British as a group and that’s what America has always been.

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