What The Wetlands Say

DSC_0062I’ve now traveled throughout all of Iowa, meeting amazing people and seeing remarkable wetland ecosystems. Across 124 blog posts, I’ve tried to share my excitement with readers about the sights, sounds…and yes, smells…I’ve experienced.

“But Paul,” you say. “Just what is The Big Picture of Iowa’s wetlands…?”

Well, certainly no one can deny that Iowa has more diversity than is immediately obvious. Despite the loss of more than 90% of the State’s wetlands, I still found natural fens, potholes, sloughs, bottomland forests, brushy swamps, wet meadows, and marshes. I observed resident and migratory amphibians, reptiles, birds, mammals and insects. Gorgeous wildflowers, intricate mollusk shells, gnarled driftwood, and the water itself, all have unique beauty.

DSC_0382My interest in history appears in stories about Native American burial mounds, traditional uses of plants, a profile of “Ding” Darling and the modern American wetland conservation movement, “ghost towns” and changing land use, and Superfund and other serious contamination…and how we’ve addressed our legacy. The story I didn’t tell, and the sites I couldn’t show, were the countless missing wetlands. The landscape still has scars and remnants of drained or filled wetlands, often quite obvious in Spring when fields are still wet, or at high flow events in streams and rivers which attempt to reclaim old oxbows or floodplains where the water naturally moved from time to time.

Sometimes a blog entry was less about the site itself, and more about what we do at wetlands—the business of wetland science and management. It’s fascinating to “read” signs of hydrology (water movement or characteristics) when a site is in fact very dry. Identifying plants and animals is a useful tool, and Iowa has knowledgeable and generous naturalists—mostly unpaid, yet quite expert—who help each other to learn the species and about their biology. We all use maps, aerial photographs (including fancy Infrared or decades-old historic shots), soil samples and marker horizons (glitter, anyone??), chemical analyses, and a well-developed series of procedures to accurately identify, delineate and classify wetlands.

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Redheads are handsome, yes…? šŸ˜‰

I haven’t talked much about how to care for our wetlands, and I’d love to do more with that in the future. Science and my personal observations all confirm that wetlands are never isolated, but are connected to other elements of the landscape. Healthy ecosystems are dynamic and adaptive, always-changing. Although we attempt to isolate or standardize the condition of a wetland, that’s always a bad idea, even if well-intentioned.

This blog is proof that, deep down, I’m a teacher…and in particular a teacher who loves to share stories. Most of my favorite memories are of wetland visits spent with my students. We get wet and muddy. We try to observe the organisms close-up (but hopefully, gently and respectfully). We learn about the conditions of water and air and soil that together, over time and through the work of life itself, make these unique and beautiful places.

bottle_itFor some additional reflection on this quest, I encourage you to listen to an interview I gave with the news director at our local radio stations, KNIA-KRLS. You’ll find answers to questions like why wetlands are important, which of the 99 was my favorite site, recurring themes through the project, and what this all means for my other professional activity.

What was your favorite memory? What would you still like to learn?DSC_0264

Number 99 at last!!

HOME AT LAST, to the final visit in my tour of Iowa’s 99 counties: my home for 20-some years, Marion County! In fact, this wetland is right on the campus of my home institution, Central College, where I’ve worked since moving to Iowa.

It seemed fitting to profile a site in my own backyard, as a sort of homecoming. Better still, I can turn over the blog to my students for this one! They’ve worked hard at the site, an old farm pond on the west end of campus, and I will let them tell the story. Please visit the web page they created as part of a group project for my colleague’s class (link below). But first, let me add a little background for context…

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The environs near the wetland/pond, part of the athletic complex. Service Day started with a rare October snow…melted off as the day warmed.

This pond has been used for years, by myself and other profs, for aquatic ecology activities. When we did bathymetry in Limnology class years ago, we found the bottom to be fairly uniform, with firm footing and water depth of about 60-70 cm throughout. Obviously siltation has occurred since then, and it is shallower and more “squishy.” However, the notched outflow on the berm (earthen dam) has eroded a bit, likely to decrease the maximum water depth as well.

As far as I know, runoff from surrounding grassy fields—combination golf practice area and cross-country course—provides the sole water input aside from direct precipitation falling on the surface. During dry weather, no water flows out; however I haven’t seen the pond actually dry.

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The pond is visible in the right half of this photo. It is almost completely covered by the tiny duckweed plants. Extensive trees and brush surrounded the pond before the crew got to work

The pond has minimal emergent macrophytes (cattail, bulrush) around the edge. Filamentous algal blooms in early Spring are followed by a thick covering of Duckweed, so an impetus for the project was my observations that the duckweed diminished both the habitat quality and our ability to use the pond. I suspected that clearing the dense plant growth from the slopes around the pond might help reduce the duckweed, and facilitate access for visitors.

Link to the student web page:

https://storymaps.arcgis.com/stories/6cd2c0ff4997425d8063650c97589e34

Pretty great, isn’t it? They did an outstanding job with both organizing a Service Day project (and follow-up extra work day), and then all the additional analyses. The web page tells the story, although there’s yet another product of their labors (I’ll share THAT, next week).

This is the last of the 99 wetlands for my epic trek across Iowa…but this is certainly not the end of the story. This campus wetland will allow this coming semester’s classes, and many well into the future, to learn more about wetlands and their inhabitants and functioning. I’m looking forward to that. But beyond this, I believe we need to step back and review the journey, and consider what it all means. Come back next week for my musings on 99wetlands, and beyond. Thanks for visiting!!

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TEAMWORK. I really do appreciate the student’s hard work and the willingness of my colleague to “loan” me her Environmental Studies class…

The Waters Linger…

DSC_0285De Soto National Wildlife Refuge sits in an oxbow of the Missouri River, along Iowa’s western border. I visited in late October of last year, so I could X-off Harrison County on the 99wetlands map. It was a gorgeous day, sunny and warm. The migrating waterfowl were present in force, and I was enjoying myself, being right there and living in the moment.

Or, I was trying to. But memories of the previous spring’s flooding were ever-present. Trails closed, roads and culverts washed out, high water under the Visitor’s Center building. Perhaps the Redheads, Coots, and Ibis all benefited from the water sitting here and there on soggy fields. But I had heard all the trouble it caused to the Refuge personnel. Emergency conditions, and all-hands working to keep things safe and secure. Up and down western Iowa, areas along the river were inundated, and the effects will be felt for years to come.

But let’s be thankful for the good news. De Soto is a beautiful facility in the perfect spot: a major flyway for birds such as the iconic Blue Goose, symbol of the entire Refuge System. When I visited, they had (finally!) reopened most areas of the Refuge, including the terrific Visitor’s Center, complete with attractive and informative displays, helpful staff, and—as I was excited to discover—an excellent bookshop!! You should come visit.

The staff here, and all those living along the river, are inexorably tied to a mighty force of nature. It affords opportunities for recreation and trade. The waters are always changing as they flow; one day a lovely vista, the next a dangerous threat. But…we really shouldn’t just shrug our shoulders at the inevitability of flood risk. As regular readers of this blog have discovered, we humans have changed the very nature…of Nature. We have altered the drainage of Iowa’s surface, delivering more water, more quickly to streams—thereby increasing flood risk along this river. We are also changing our climate by dumping huge quantities of carbon into the atmosphere. Climate change is happening, and it includes alterations to the water cycle. Expect more flooding here at De Soto, and elsewhere across Iowa…and beyond.

DSC_0303In less than three weeks, I’ll head to my local caucus. We Iowans are the first Americans to express our opinion about those running for President. You can count on this: I’ll chat about climate change with my friends and neighbors who share my party affiliation, if an opportunity presents itself. I will urge those around me to step up to the challenge of climate, and call on our leaders to do the same. I hope that you’ll have that conversation in your caucus, or with a parishoner over coffee after church, with a friend at the pub, or through social media. Please…we need to talk about the future, about the climate, about our wetlands…and what we leave as a legacy. Let’s make sure our care and dedication are what lingers after us.

“Eyes of the Water,” watching Flamingos!

DSC_0094Our study-abroad students and I recently beheld one of Nature’s most thrilling sights: flocks of hundreds of American flamingos (Phoenicopterus ruber) in in the wild! There are only a few places you can get “up close and personal” with these magnificent birds, and the shallow coastal waters around the Yucatecan town of Celestun is one of those spots. This trip was one of the last things we do with our group, and it was as much a celebration of this place and our love of it, as it was a chance to watch birds.

After a couple hours’ drive west of Merida, we came upon El Puente del Rio, a bridge over the river, although honestly the alternate name locals use (La Laguna, the lagoon) is more accurate. Really, this narrow body of water is simply a shallow, protected inlet of saltwater; it is directly connected to the Gulf of Mexico.Ā  Mangrove trees border the water on all sides.

DSC_0089Near the bridge is a visitor’s center with restrooms and ticket office. Unlike olden days, the excursions to view the birds are now organized and efficient. Fine little boats await at a dock, and their skippers are knowledgeable and friendly, ready to take your ticket and begin your voyage. Hold onto your hats, because you’ll power over to the flock pretty quickly.

Guidebooks always caution readers against goading the guides into approaching the birds too closely, but I doubt it needs to be said. These folks appear to love the birds, and know full well that the flamingo’s well-being is more important than any particular visitor getting just the right photo or a closer look. All the questions I’ve asked the guides have been answered quite authoritatively, so they clearly understand the birds and the need to refrain from stressing them by getting too close. Moreover, the guides have been more than happy to point out other birds, too…and seem to have a really good eye for finding the various herons, osprey, cormorants, and more.

DSC_0105There surely are a LOT of birds, and other wildlife, to enjoy. Although the waterway appears uniform, it really isn’t. Note the patterns of upwelling and mixing occurring here and there, giving the water different colors and degrees of cloudiness/transparency. We should expect those differences will be important to the various small, planktonic organisms in the water, and therefore to all theĀ  organisms up the food chain, including ultimately those flamingos.

I’m told that much of the inlet has a similar depth (obviously suitable for long-legged wading birds), but shallower spots are found here and there—your boat’s skipper will need to tilt up the outboard motor to navigate them. After tooling around the broad, open area, it’s time to visit an entirely different ecosystem: El Ojo de Agua, the “Eye of The Water.”

DSC_0135We navigate a channel through the mangrove forest, and deep within we find inside yet another type of forest entirely, one with taller trees and a diverse community or plants and animals. It all surrounds a series of pools, upwelling springs of freshwater (agua dulce, “sweetwater”). The freshwater has traveled through the karst (limestone shelf) that underlays the Yucatan Peninsula, flowing from the south (all the way back to the Puuc Hills, perhaps) and spreading out here as it finally drains to the ocean, bubbling up within a salty coastal wetland!

DSC_0141Our boat pulls up to a dock, and we step out onto a boardwalk through the forest. Some visitors swim in the clear, fresh pool, but not me—I am working. On some trips, I’m lecturing to the students; other times we may collect data on salinity or other characteristics of the water. Today, I’m mostly observing birds. This is a great place to see almost anything: songbirds of the forest, raptors, waterfowl of the coast, or perhaps hummingbirds working the flowering vines climbing up the trees. I pause to enjoy a Yellow Warbler (Setophaga petechia), a common visitor to northern wetlands. I wonder if I’ll see him again in a month or two, up in Iowa…?

In the meantime, I will enjoy my time here in the Yucatan. Please come back next week for more about Celestun, and this part of Mexico. Thanks for your visit.

The Nitrate Commons

P1140132Over the past three weeks, we’ve visited a cluster of three northwest Iowa counties: first Calhoun (Twin Lakes WMA), then Buena Vista (Storm Lake Marsh), and last week it was Sac County (Kiowa Marsh). The center of that cluster is about 90 miles (145 kilometers) due northwest of the state’s capitol (and largest city), Des Moines. It might be more useful, however, to measure the river miles—how far water flows downstream from those counties. And therein lies the tale of a serious nitrogen pollution problem, recent legal action, and a glaring example of our collective environmental commons.

This concept of The Environmental Commons was explained by Garrett Hardin in a classic 1968 paper in the journal Science entitled The Tragedy Of The Commons. That article is about human population growth, but the premise of the Commons itself works for any shared resource. In the article, Hardin presents a parable of a shared grazing space (a village green), called The Commons, and presents the choice faced by any user of a commons (e.g., sheep herder):

…The rational herdsman concludes that the only sensible course for him to pursue is to add another animal to his herd. And another; and another… But this is the conclusion reached by each and every rational herdsman sharing a commons. Therein is the tragedy. Each man is locked into a system that compels him to increase his herd without limit–in a world that is limited. Ruin is the destination toward which all men rush, each pursuing his own best interest in a society that believes in the freedom of the commons.

The tragedy, of course, is that everyone acts rationally, until the Commons (shared resource) is “ruined” (depleted). Every user of the Commons only takes a little bit, and never intends to cause harm. And yet overall, harm is the result. This certainly has happened with overgrazing on shared public lands in the United States, a giant “village green” if you will.Ā  However The Commons can be ANY shared resource, such as harvestingĀ  from ocean fisheries. LittleĀ  by little, through innocuous individual actions, populations crash, and a shared resource (commons) is ruined.

dsc_0810Now, let’s think about water pollution. A common form of nitrogen (nitrate, NO3) is found in Iowa’s waters: rivers, lakes, groundwater. Its presence is normal and natural. Adding just a little bit from a pipe or through runoff over the land surface is to be expected, and not a problem. Organisms in ecosystems, such as found in an Iowa stream, can and will use/process/transform the nitrate. In fact, nitrogen is a fertilizer: it helps plants grow. This is not inherently a problem.

However—at some point, the individual contributions add up, and we collectively add so much nitrate that our water bodies become degraded. This affects the stream or lake ecology (they become “impaired” in the regulatory sense), and the nitrate flowing downstream joins the Mississippi River, where it eventually reaches the Gulf of Mexico. Down in the Gulf, it contributes to hypoxia, the infamous Dead Zone.

The nitrate problem isn’t just ecological, however. Some water suppliers draw from surface water bodies, or shallow groundwater connected to surface waters. Their customers will then drink the high-nitrate water. For example, the Des Moines Water Works supplies domestic (drinking) water to half a million residents in central Iowa. The Water Works draws from the Racoon River whose large drainage area (watershed) lies to the north and west. Nitrates within the watershed are carried to the river flowing downstream and then affect the water quality, raising levels of nitrates above the legal limit (10 parts per million of nitrate-N). Nitrate levels exceeding the limit happens several times a year, and forces the Water Works to use an expensive nitrate-removal process.

As a result of this added operating expense, the Des Moines Water Works then sued three public drainage districts located in upstream counties. Those are the counties featured in the last three weeks on this blog.

Note that nitrates are added to water in many ways: effluent from wastewater (such as septic systems or a city wastewater treatment plant), animal waste, runoff from farm fields or golf courses, and the very lawns at our residence—literally, our own back yard. They can all add nitrates, and they are all implicated in our common nitrate challenge.

The Water Works lawsuit was dismissed, and that isn’t surprising. Too large an area of watershed, with too many sources of nitrates, are contributing to the river’s water pollution—it would be quite difficult to assess damages against a few particular entities. The watershed, and its ability to safely process nitrates, is a shared resource–a commons. We all own it, we all are effected by it, and we all contribute to a common nitrate problem.

dsc_0168What then shall we do?? I believe there are three parts to this challenge:

First, we should have an honest conversation. It’s long past time pretending that no problem exists, or that it will solve itself. When I arrived in Iowa in 1998 and learned of ongoing legal battles about nitrates in water, I never dreamed we’d be fighting about it all these years later. We need to acknowledge the multitude of evidence, consult with the people who have worked hard on this problem, and commit to finding solutions.

Second, we must strategize about the possible solutions. Knowing how nitrates get into the water, and what acceptable levels (water quality standards) should be, we can talk about ways to account for the sources and how to reduce the inputs.

Third, we must implement well-planned measures to get the job done. This is where economic and political reality comes in—what strategies will be widely supported, and workable? What is cost-effective and achievable in a timely manner? We should think about buffer strips and cover crops, and better wastewater treatment, and bioreactors, and many other great ideas.

Oh…and wetlands. As discussed many times on this blog, wetlands “clean the water,” including removing nitrates. Preserving and protecting our existing wetlands, and building or restoring others, will surely help us save our Nitrate Commons. Let’s get to work!

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Clean-Water Factory (with ducks…)

dsc_0369Before visiting an area on this 99wetlands quest, I sometimes read a technical note or scientific journal article to provide some context. Before visiting Kiowa Marsh in Sac County, I found a 1917 study in the Wilson Bulletin by J.A. Spurrell, described the condition of the County before settlement by Whites. The eastern half of Sac County had been covered by the Des Moines Lobe, a giant glacial surface coming down from Minnesota, the Dakotas, and Canada, and looking like a giant tongue. In eastern Sac County it formed a classic pothole landscape, prairie dimpled with shallow water features and wetlands. To quote the article,

“Correction pond, Lard lake, Rush lake, and many smaller ponds are now farm land.Ā  …The drainage from Wall lake, the only one remaining, flows into Indian Creek.”

dsc_0371And this is where we have good news: a large wetland restoration at Kiowa Marsh, part of the Indian Creek watershed. The marsh is owned by the Iowa Department of Natural Resources, but the restoration was a cooperation withUS Fish & Wildlife Service, and Ducks Unlimited and used funds from the Environmental Protection Agency. That link takes you to an Ammoland.com article, and yet other than the headline, only a passing mention of wildlife is made. However, statistics about the wetland and water quality are provided:

  • Indian Creek is part of drainage leading to the Raccoon River…which provides critical drinking water for more than 450,000 Iowans—or roughly one-sixth of the stateā€™s entire population
  • ditches that empty into the marsh…drainages have for years served as a superhighway for soil particles and nutrient runoff that enter Kiowa Marsh and eventually flow into downstream creeks, rivers and reservoirs.
  • the restored wetlands will reduce sediment delivery to Indian Creek by approximately 652 tons/year and will help trap and recycle an estimated 847 tons of phosphorus per year
  • total cost of these restoration efforts was nearly $300,000 and will pay back significant dividends to Des Moines area water users
  • …and so, once again we face the clear truth. Yes, these wetlands WILL provide valuable habitat to waterfowl (and thereby, to hunters or birders). But the reasons wetlands are protected under the Clean Water Act, or the reason this particular wetland was restored using monies from the EPA, is that—whether they provide for the classic wildlife triumvirate of “Fur, Fins & Feathers,”—they first and foremost are about the water. No wetland is ever “isolated.” Our wetlands work to clean our water.

dsc_0365In correspondence with Clint from the DNR, he mentioned the considerable work in making sure that drainage from neighbors is properly incorporated, and that water storage and movement in the wetlands can be adjusted to attain project goals. Additional work on the north basin was in progress during my visit; this hard-working wetland will have even more benefits very soon.

The great thing is, in restoring wetlands for water quality benefits, we also support habitat for wildlife. A sign at Kiowa refers to the Waterfowl Production Area…AKA “duck factory.” That’s in addition to the restoration funding having the stated goal of being…a clean water factory!

Come back next week as I “connect the dots” of water quality in these three recently-profiled counties, and think about the recent news reports and legal action involving Iowa water quality, and the considerable work we still have to do. And I may have a suggestion to help with all this (spoiler: it involves wetlands!!). See you then.dsc_0363

The Wetland as Traffic Cop

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entrance near the south end of the marsh, along Hwy 110. Note the wood duck housing complex.

Last week, we visited the Twin Lakes in Calhoun County. We saw how a wetland adjacent to South Twin Lake sits at the base of a slope, catching silt, sediments, nutrients, and other substances in runoff. Wetlands naturally “clean the water,” as we have discussed many times. This week, let’s expand that idea a bit.

Little Storm Lake in Buena Vista county is not really a lake at all: it is a wetland adjacent to the northwest edge of Storm Lake, an actual (shallow glacial) lake. It’s a great place to think about a wetland “cleaning the water.”

In my Limnology class, I sometimes ask students to think of a lake as a giant container of water in which chemical reactions happen. Much like the glassware holding aqueous (watery) solutions in their chemistry classes, a lake will be affected by light and heat energy, circulation (that is, mixing), atmospheric pressure, and other inputs to the system from outside. Reactions in the water will depend on pH, dissolved gasses, and the activity of organisms. Particular chemical reactions all occur (or not) in that context. This “lake as a big glass beaker” mental image is then kept in mind as we discuss specific chemical parameters and reactions.

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access road leads in to water control structures, and forms a berm or dike

Then again, a wetland (like Little Storm Lake) is perhaps like a chemist, adjusting the characteristics of water entering the lake. It’s often said that a wetland “cleans the water,” but truly a wetland transforms chemicals in the water in ways we categorize as “cleansing.” For example, silts and sediments settle out of the muddy water, depositing (and slowly filling) the wetland; the water leaves the wetland “cleaner.” Phosphorus sorbs (adheres to) the silts and sediments, and so are removed from the water as well. Nitrogen is transferred from water to air, by an entirely different process—denitrification—and we’ll consider that next week. These are all examples of the “wetland as chemist.”

Little Storm Lake is a natural marsh, but it was recently extensively modified to move beyond that role as “chemist,” into a role as “Traffic Cop.” Much like a public safety officer directing vehicles safely and efficiently on roadways, this wetland is now equipped to direct the flow of water safely and efficiently. Let’s have a look!

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dueling water control gates

About eight years ago, the DNR partnered with the local lake association, non-profit groups, university staff and others to undertake a large wetland restoration (more correctly, engineering enhancement) and lake protection project. This Storm Lake page describes the project, and a DNR lake restoration white paper has more details (starting on page 17). The basic idea is this: construct walls (dikes), and channels or culverts (plumbing) store and move water as desired; they prohibit fish movement (ideally, keeping nuisance species like carp under control); and workers periodically dredge out the accumulating silts and sediments.

If a wetland like Little Storm Lake exemplifies the slogan “Better Living Through Chemistry” by the transformations cleaning the water, then this project now adds “Better Living Through Plumbing.” Water in this wetland can be adjusted to appropriately process high flows, normal flows, or even to drain the system of water. Drying out a wetland seems counterproductive, but an occasional decrease in water depth and even emptying (“drawdown”) encourages seed germination, facilitates maintenance, and kills off undesirable aquatic species. If the wetland (and adjacent lake) function is determined mainly through water dynamics, then this project provides a powerful tool.

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Probably a pumping station, although it also reminds me of a nuclear reactor. Cordoned off, so I couldn’t examine it well enough to know which.

Furthermore…let’s be honest: Iowa’s streams and rivers, such as the one flowing into this wetland (Powell Creek), carry a heavy load of runoff…and everything runoff brings. Wetlands are helpful—perhaps critical—in protecting our water quality. It’s a theme we’re considering in these weeks, with wetlands from three counties and an upcoming essay considering the challenge we face regarding Nitrogen in particular. I wish to address the news reports and controversy, and ask if wetlands might just help us solve the problem. Please come back in the coming weeks for that discussion.

In the meantime, if you’re near Storm Lake, check out the marsh. On the north side, near the intersection of state highways 7 and 110, you’ll find the Little Lake Discovery Boardwalk. Informational signs adorn a floating walkway among the cattail, and a tall tower provides a stunning view (complete with free telescope!). Admire the flora and fauna and another hard-working wetland…”at your service.”

 

 

Our Carbon, Our Wetlands, Our Future

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Carbon cycles around the biosphere. It may be stored as fossil fuel, then burned and released to the atmosphere, incorporated into plants or soil, dissolved in water, etc.

A couple weeks back, the United States Government issued a report on the threat posed by Global Climate Change. It made a lot of important points, but unfortunately much of the message was drowned out by reporting on President Trump’s unwillingness to fight, prepare for, or even acknowledge the threat of climate change. Lest you imagine the report as ramblings of tree-hugging, granola-munching, nature freaks…rest assured, the report is interdisciplinary and a collaboration, and focused on the threat to the health and well-being of the American people. And that threat is considerable.

Why think about a threat to the American people and society when contemplating climate? A little historical perspective might be useful, before we head to the swamp…

We’ve had climate change before, and it was incredibly disruptive. For example, a major immigrant group in the USA are those of Irish descent. A major factor in Irish emigration to North America was The Great Hunger (so-called potato famine) of the mid-1800’s. That event was the result of a fungal pathogen (blight), as is widely-known. Less-known is the contribution of climate: cool, wet conditions—and flooding—aiding the spread of the disease. This great human disruption, and all the historical ramifications, is due at least partly because of meteorological conditions.

More recently, an All-American diaspora happened with the Dust Bowl of the 1930’s. As the name implies, great clouds of dust (wind-blown soil) blackened the skies and blanketed the cities of the East. This resulted from poor agricultural practices, but was triggered by an intense drought. It was mainly residents of the Great Plains affected, but also Iowa. And our nation was forever changed by this event—socially, economically, politically.

All in all, it’s obvious that climate disruption leads to disruptions of human society, too. Those examples are two of many around the world, localized or regional, demonstrating the danger of climate change; we would be wise to take heed.

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We have transformed the Iowa landscape (such as at the abandoned town of Owego, seen here). We have also transformed the carbon cycle with our land use and technology…but the change to the atmosphere is not visible.

Our science has improved steadily over decades, helping us understand the contribution of human activity to a changing climate. In short, we ARE changing the chemistry of the atmosphere (by adding carbon to it), and we know the increased carbon concentration changes the climate—to become warmer overall, but with many variations in effects, especially locally severe events. I have added my name to a series of statements about climate change, the most recent (2018) calling for buildings and other infrastructure to be designed with climate change in mind; we need to prepare for what climate change will do…or rather, is doing. (It’s no coincidence that the press conference was held in downtown Cedar Rapids, site of devastating flooding).

Now to the wetlands! Swamps, marshes, fens, and the rest—they affect, and are affected by, climate.

  • Wetlands store carbon, especially in soil or undecomposed organic material (peat), such as the spongy layer in a fen. Preserving intact, functional wetlands keeps that carbon locked up, and continuing growth adds more stored carbon.
  • Wetlands store water, a valuable service to lessen downstream flooding. (Climate change will mean more severe weather events, and worse consequences).
  • Climate change will impact biodiversity, so preserving the few remaining Iowa wetlands—in good condition—is even more important. Rare, threatened and endangered species of animals and plants are found more frequently in these wet habitats than might be expected by the area wetlands cover.
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Will climate change increase the risk of fire in ecosystems? It is a likely scenario.

What will climate change do to Iowa wetlands (or those in other places)? And what will our wetlands do to the climate? I’d like to explore those questions further. One important consideration might be decomposition processes: the decay of organic matter (such as tissues of dead plants) and the subsequent return of carbon to the air. I recently did a little trial run using the Tea Bag Index and shared with my Ecology class. It might be fun and useful to follow up on this in the future, including “tea bags” of a more traditional design: plant tissues from local sources placed in mesh bags (fashioned from window screen). Understanding wetland decomposition could provide useful insights into global carbon dynamics.

Two other recent episodes in my Ecology class also come to mind. This week, we are talking about chemical cycles in ecosystems—including the carbon cycle—and as we look at a box-and-arrow diagram in the textbook, I like to remind students that real ecosystems don’t exist in boxes—they are connected to the rest of the biosphere. Energy, water, chemicals, and even organisms move in, out, and through ecosystems, all the time. And we would be wise to remember our connections with the Earth’s ecosystems.

Also, we had a special visitor in class last week. Derek, a former student now employed by Iowa Natural Heritage Foundation, came to recruit summer interns. Even better, as he described that worthy organization, he made a point of distinguishing what they do—stewardship—with the more typical idea of land or natural resource “management.” Indeed, we really should recognize that our predecessors bequeathed us a beautiful, life-filled planet to enjoy and be nurtured by. And we should care for, then pass along, a healthy Earth to those that follow us.

The Society of Wetland Scientists has asked us, the membership, to reach out beyond our group, reminding everyone of the significance of wetlands in climate change. We are asked to encourage you to take measures to address our shared carbon problem. Consider this blog post an invitation. What can we, together, do to raise awareness, and to help us work towards solutions?

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Our actions now, will shape the environment for centuries. Let’s work to make a brighter future!

Teatime For Wetlands

DSC_0546An exciting trend in recent years, is the “citizen science” movement. Scientists invite the public to collaborate on research, and everyone wins: scientists have more data, everyone else becomes engaged (maybe even excited??) about science, and together we grow our knowledge about Nature. I’m a big fan, regularly participating with my students in Project BudBurst (timing of seasonal events in plants) and Frogwatch (amphibian monitoring), and others from time-to-time.

At Barber Creek Wildlife Management Area in in eastern Iowa (Clinton County), I participated as a “citizen scientist” following the protocol of the Teatime for Science. The idea is brilliant in its simplicity: weigh and then shallowly bury tea bags, dig them up after three months, dry them and weigh again. Natural decomposition processes cause the tea to lose weight, with that weight loss being affected by factors in that specific environment. Two different teas are used, a fast decomposer (Green tea) and a slower one (Red tea). Comparing decomposition over time, and in sites around the world, helps us understand this important aspect of the carbon biogeochemical (matter) cycle.

Tea bags as “decomposition detectors” or “global carbon-cycle meters?” EXCELLENT.

DSC_0548Barber Creek is a State Wildlife Management Area, so I contacted the local Department of Natural Resources officer for permission andĀ  he provided useful advice as well (thanks Curt!). The site includes several deeper ponds (likely, old oxbows) near the Wapsipinicon River, bottomland floodplain forest, and several shallow marshes on higher ground (perhaps farmed in the past, or surrounded by farmed ground). One of those isolated marshes is a recent addition, the Bruckman wetland. That habitat seemed easily accessible, and had characteristics similar to two other wetland sites (Brush Creek in Jasper County and Nishna Bend in Shelby County) also used for this tea experiment.

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As I found in my touching tale of deer-aided work at Brush Creek, the transects and holes with buried tea bags may be difficult to relocate after the requisite 90 day period in the field. “But Paul,” you say. “Didn’t you use GPS to locate your holes/bags and also the ends of the transect?” The answer is “No,” because I had no reliable signal (a problem I have alsoĀ frequently encountered with cell phone coverage in rural Iowa). I used old-fashioned reckoning with landmarks: sketch a diagram lined up with reference points like a nesting platform in the center of the wetland, and a utility pole or building. It’s not ideal, but it works well enough. I was indeed able to find my transect after 90 days.

DSC_0544Unfortunately, hydrology is variable…and the transect was under deep water when I returned. I couldn’t find and dig the individual holes and buried tea bags. In the end, I had to walk away from the site, and “write off” the tea bags and data they represent. The thing is, this the research protocol has a 10-day window during which the bags are relocated and retrieved, and my return visit was near the end of that window of opportunity. So, the bags—what’s left of them—are still out there. This sort of thing happens a lot in research (at least, MY research). For every “Eureka!” I shout, there are 100 grumbles or face-palms. Even with a well-established, user-friendly protocol, difficulties appear. At some of my sites, I found the hole (and marker), but not the buried tea bag. Or, the tea bag was torn (can’t get an accurate weight—write that one off). Or and animal or plant infiltrated the bag; again, discard that one. And on and on.

But I shouldn’t complain. This was a “pilot study;” I wanted to know if I could obtain the tea at all (found an overseas vendor who will ship to USA), find places to work (yes, several), habitat characteristics and specifics, and various other practical considerations. And I learned a lot from this; I am considering doing more of this in the future (with some alterations to the method).

Later today, my BIOL 229 (Ecology) students will submit answers to questions about this experiment. It’s fun to use real-life field work, even if only a small pilot study, in my class. We actually compared decomposition (weight loss of tea) in the two wetland sites and two upland sites. I entered the data into a statistics program (MINITAB) and compared results using Generalized Linear Model (GLM) with associated post-hoc tests. I can’t go into details now (must let the students work out own interpretations!) but here’s a box plot and stats table for you to enjoy. Later I can make a comment and share my interpretation.

Also, next week, I will share some thoughts on what tea decomposition tells us about changing carbon dynamics in wetlands, and why that process—or similar action anywhere on Earth—is so very important. It is the environmental, indeed societal, challenge of our time. Be sure to stop back and hear all about it. Thanks!

Fall Colors in the Wetland?

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Pond on the Central College campus. Color change of trees, some have dropped leaves. Can you see the Great Blue Heron on the left side of the island?

My local hardwood (deciduous) trees are undergoing fall color change. Local trees are glowing gold, ablaze in red, and even a few have a purple color. It’s strikingly beautiful. Since I teach a bit of botany, I feel compelled to talk about this in class, and I also encourage students to keep track of the color change and the dropping of the leaves. And today, I ask you: why do the trees do this? And, would wetland trees differ from the rest? Read on!

The basic idea is explained well enough on-line: trees drop leaves in preparation for winter, when weather renders those leaves a dangerous liability. Some pages describe the chemistry of the colors and even show photomicrographs of leaf tissues. The traditional understanding is that leaves contain chlorophyll, a green pigment which is most visible to us most of the time; but chlorophyll fades, revealing other colors from “accessory pigments.” But about a decade ago, another part of the story was described: certain red or purple colors—anthocyanins—are specifically produced this time of year as a sunscreen, protecting leaves from UV light damage; this helps trees hold onto the leaves longer. Synthesizing anthocyanin is a chore, but is worth it, because doing so allows the tree to recover nutrients from the leaf before leaf they drop.

Of course it’s only “worth it” to synthesize anthocyanins and recover nutrients, when nutrients are scarce. If nutrients are plentiful, why bother? And that study compared floodplain trees (where nutrients are plentiful) with nearby uplands (where nutrients may be limiting to tree growth). And sure enough, floodplain trees were less colorful (specifically, levels of anthocyanins). So, we might expect other floodplain wetlands to be less-colorful (at least in certain colors).

DSC_0237I thought about this when I recently visited the Nolan Addition (Fuller Addition??) in Keokuk County (near the borders with Iowa and Washington counties). The site was beginning to show autumn color, and I had a pleasant walk, despite high water making it tough going down on the floodplain. I did see signs of fall color, but…the colors were a bit lacking, frankly. To what extent was I ahead of the fall color peak? Maybe a bit, although I did see color in uplands nearby. I’d guess that, as predicted, this floodplain wetland was less colorful, because the trees had plenty of nutrients available.

Colorful or not, I enjoyed my walk…seeing a story written in the scene around me. The recent agricultural past was still present in signs of water control (drainage, levees). The flooding of the nearby English River was very recent, and much of the low area was wet (inundated)—a floodplain wetland doing its job! Good thing, too-lots of rivers running high all around at this time. Anyway, the smell was musty, vaguely fishy; the vegetation was covered in some spots by deposits of silt left behind when the water was even higher.

I enjoyed a little color here and there, even if some of it was on ground just a little higher than the floodplain; for example, Sumac (Rhus) produces a blazing scarlet in Fall, and always catches my eye. The low ground had plenty of Birch (Betula) and Cottonwood (Populus)Ā  another deciduous tree.

DSC_0228A floodplain wetland receiving nutrients from its stream is natural and normal, and although it may dim the colors this time of year, it is something really important to us all. Nutrients deposited and retained in a wetland, are not flowing downstream to cause water quality problems. Watch for future posts about this topic, oh-so-crucial to Iowa. In the meantime, I encourage you to get out and see those lovely Fall colors. Enjoy!