Somewhere, All Of The Time

DSC_0155A professor once explained the concept of Conservation of Matter using the truism “Everything has to be somewhere, all of the time.” Therefore water (and all other matter on Earth) can change form or location, yet is always still somewhere, and it is always, undeniably, water. That’s also why we should thoughtfully consider the hydrologic (Water) cycle, and the role wetlands play in that cycle.

In many parts of Iowa, the Spring of 2019 has been a challenge. Record flooding has occurred in areas, in some cases with catastrophic results—enough to be an official, declared disaster. But any flooding is a problem for the landowners or residents affected—it’s a disaster to you, when it’s your basement, field, town, or a place you live or work that’s flooded. The functioning of the water cycle has very real, even deadly, consequences.


This was on my mind as I recently drove around a very soggy northwest Iowa. Teaching at Iowa Lakeside Lab gave me a home base to see some really wet areas and the effects of flooding. For example, just a little east of the Iowa Great Lakes in Emmet County is Estherville, site of significant flooding by the Des Moines River. I believe these photos tell the story of sandbags and flooded roadways and what happens when “the river is up.” I took the photos while scouting for a trip to Fort Defiance State Park, located just outside Estherville. I was later surprised and relieved to find that the river flowing through the park, School Creek, was only a little high, and I could still work in it with my Aquatic Ecology students. How fortunate for us, but…why such a dramatic difference in the water near Estherville??

DSC_0165No doubt, many factors affect a river’s flow. I certainly don’t believe that wetlands are the only difference between the Des Moines River and School Creek at Estherville. Nevertheless, School Creek does in fact drain a large nearby wetland complex, Fourmile Lake. Recall from previous blog posts, how wetlands “smooth out” hydrology, absorbing large amounts of rainfall or snowmelt, and then slowly releasing it to groundwater or surface outflows. So if water has to be “somewhere, all of the time,” perhaps a wetland is a good place to be—as opposed to a “flashy,” flood-prone stream.

As it turns out, my students and I also discovered that this wetland complex is beautiful, and filled with amazing plants and animals. For example, we enjoyed catching inverts in our dip nets, seeing red-wing blackbird nests and adults, hearing marsh wrens call, and much more.


I’m not the only Lakeside Lab instructor to visit Fourmile Lake! You might consider checking out the work of my colleague Alex Braidwood of the amazing Artist-In-Residence program (Lakeside AIR).

Have you ever visited the Fourmile Lake wetland? Are you familiar with the flooding situation this year? Leave a comment or question! Thanks for reading…


Flamingos Fly; Us, Not So Much.

DSC_0336Last week, we visited the Yucatecan coastal town of Celestun; the study-abroad students and I had a great time seeing birds, especially the iconic flamingos. Unsurprisingly, I chatted with the group about the landscape and ecology of the place—I believe appreciating the science and history of place only adds to the aesthetic enjoyment and fun of travel.

But let me add to that a bit. At Central College, we believe education (including study abroad) is about more than the individual student. Our mission is to be a force for good: the world should be a better place because of what we do. I hope that many travelers aspire to a similar mission: enjoyment and memories, of course…self-improvement, hopefully…but even more, our travels can make human connections, benefit the people we meet, and support preservation and enhancement of special places.

Celestun is surely such a “special place.” So, it’s great that we spent time and money there: we enjoyed the birds we saw, and our excursion fare financially supported the boat skipper and therefore, the local economy. We ate lunch at a restaurant on the beach, so the food-service staff earned income from our visit. We can all feel good about that!

DSC_0363Nevertheless, I look ahead to the future with some trepidation. Mangroves and other wooded areas of the Yucatan Peninsula are under threat. The loss of those mangrove forests, and the carbon added to the atmosphere as a result, exacerbates atmospheric warming…which in turn will accelerate sea-level rise. As the ocean surface creeps up, the shoreline will creep inland, submerging coastal areas. I’ve spent pleasant times in and near the coastal city of Progreso, and worry how it will fare—the whole town is barely above sea level today.

We have committed the world to an altered climate, for decades to come. Will the flamingos survive the resulting changes? Actually, I imagine they’ll have an easier time of it than we will. They are migratory, moving east-west across the Peninsula during the various seasons; they follow food, find nest sites, and will naturally adjust their behavior “on the fly” as it were. When the environmenta changes, they’ll adapt.

But what about the locals I met during my visit? Of course, they’ll need to adjust, as well. I’m optimistic that tourists will still come, even if the flamingos don’t flock and migrate in the same way at the same times. Those fishing/crabbing this inlet or the nearby Gulf may need to change their equipment and techniques, but let’s hope the seafood is still there and plentiful. I’m cautiously optimistic about some aspects of climate change.

DSC_0298However, the change could be scary, and I hope we will wisely think ahead and make appropriate plans. Part of my work while in the Yucatan was teaching a seminar called Climate Change: North & South. Students wrote term papers, including some predicting and planning for the world they will inhabit. With ideas like how best to warn coastal residents about the hazards they face; helping communities make climate-disaster contingencies; anticipating and avoiding climate-related health risks…the students are smart and energetic. They give me hope! I hope you’re mindful and determined, too.

To finish up: may I humbly request your assistance? Please travel to wetlands and other natural features, near and far, and support those working in them or to preserve them. Talk to others about climate change, and encourage our leaders to acknowledge and respond to the threat. And share your joy and wonder about our beautiful planet…we all need that uplift, now more than ever! Leave a comment here, post to your own blog, work the social media…or perhaps take a young person for a little fun in the outdoors. Have fun!!DSC_0291

“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.  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 the  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.

“Land Without Soil Or Water”

DSC_0608Greetings from Mexico!

This is the first of several entries about my time in the Yucatan Peninsula, where I’ve been working as the visiting faculty member for my institution’s study-abroad program. I’m teaching classes on climate change and introductory environmental science, and of course I’m visiting wetlands when I can.


Map by Kaldari [CC0], at

The Peninsula sticks up into the Gulf of Mexico (separates it from the rest of the Atlantic Ocean), and is almost exactly due south of Iowa. The land is karst: most of it is a very flat, limestone shelf. Supposedly early Spanish visitors referred to it as “a land without soil or water,’ because of the thin soil and exposed bedrock; that karst is very porous, so no lakes or streams/rivers exist, either. Much of the region is scrub-shrub (very open, dry habitat) punctuated with sinkholes/caves (some filled with water).

The southern part of the Peninsula rises into the Puuc Hills, and is more lush and forested. Our Program participants visited the Millsaps College Biocultural Reserve known by its Mayan name, Kaxil Kiuic. What a wonderful place, and doing really interesting and important work on archaeology, rural development, and conservation.

DSC_0659AND THEY HAVE A WETLAND! Because of the geology, not many wetlands exist on the Peninsula (except of course along the coast—watch for more about that in future posts). This wetland was made by the staff here, and for a purpose: this is a working wetland. Specifically, this system “treats” (cleans) wastewater. It’s especially important to use care with wastewater here—in this karst landscape, any polluted water will quickly find its way down into the groundwater, and the pollution will flow through it.

And any surface water is precious to wildlife. Lacking ponds or streams, any little puddle is effectively a “watering hole” and valuable to the animals here. We visited such a water feature, and were delighted in all the birds we observed during our short daytime visit.

Of course, this is the land of the Jaguar, and yes, they can be found here. You are most unlikely to see one of these cats, but tracks and scat tell the story—but now, camera traps can “catch” El Tigre as well. And a watering hole is just the place to do it.

DSC_0673I hope to visit this place again, and take a closer look at this little wetland. There’s much else to see at Kaxil Kiuic, too…and some wonderful people. In the meantime, watch for future posts of my wanderings in the Yucatan. Thanks for stopping by!!

The Wetland as Traffic Cop

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.

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!

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.

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.”



“Pond,” “Lake,” or “Wetland…?” Whatever.

Pretty houses and cottages along North Twin Lake. A State Park with pavilion and restrooms is nearby, but no camping is available.

The Twin Lakes (North and South) of Calhoun County are a good example of the old question, “what’s in a name?” As a Limnologist–someone who studies water bodies on the continents: ponds, lakes, rivers, streams…and of course, wetlands!—I am sometimes asked how to differentiate between these systems. People want to know for example, when does a pond have sufficient surface area, or depth (or both?) to properly be called a lake?

For better or worse, there IS NO “official” distinction between these terms. (Really!) Suggestions involving the photic zone depth, or stratification, or minimum area…they are all attempts to be helpful, but are nevertheless always arbitrary. Here, someone decided that (likely in consideration of surface area), the Twin Lakes are each truly “lakes,” and of course the name reflects that. According to the Iowa DNR, North Twin Lake is deeper (ranging in parts to 12 feet/3.7 meters), while South Twin Lake is mostly between four and five feet (1.2-1.5 m) deep. South Lake is about a third larger in surface area, however (600 vs 453 acres/243 vs 183 hectares). In this part of the world, those are large enough to be considered lakes, and who am I to say otherwise?

DSC_0350Whatever name or category we choose, these are certainly shallow, productive systems (i.e., lots of algae or pondweed growing). That productivity will support a food chain and provide habitat for fish. But too much productivity makes murky water which is less appealing for swimming/boating/other recreation. A common question asked of any limnologist is “how do we reduce the algae/weeds in our pond/lake?” Of course, the answer is “stop fertilizing the pond/lake.” If you don’t want so much plant growth, don’t put silts/sediments, or growth-enhancing chemicals such as nitrogen or phosphorus into the water. Those chemicals increase the productivity of the green photosynthetic organisms—that’s why we consider them “fertilizer.” A nutrient and erosion control strategy is exactly the prescription for Twin Lakes proposed by experts from Iowa State University.

“But Paul,” you say. “Where do wetlands enter in?” Regular readers know that defining, delineating, and characterizing ecosystems are part-and-parcel of the wetland business, more so than other ecosystems. So, we are simply expanding our questions and checklists for “how to define a wetland” to use in ponds/lakes. Fair enough.

Water flows from lands upslope (left) down to South Twin Lake (right)

More importantly, wetlands lie between the land and water. Ecologically, wetlands have characteristics intermediate between terrestrial and aquatic systems. Hydrologically, wetlands often catch runoff, located in a spot where they physically intercept water flowing overland towards a water body (like a lake!). Near the south shore of South Twin Lake, down-slope from farm fields and US highway 20, lies a classic “cattail marsh.” This wetland contains a large area of cattail (Typha) plants, with muskrats (Ondatra zibethicus) and a few willow (Salix) trees. The wetland surely catches runoff heading toward the lake, removing silts and nutrients. Wetlands really do “clean the water,” so visitors to the lakes and lakeshore residents benefit from the work done by the wetlands.

Over the coming weeks, we’ll visit another couple wetlands designed and managed to protect or improve water quality. Let’s think about the challenge of water quality of the specific lake or stream near those wetlands; also keep in mind that the challenge of water quality in Iowa, in particular a form of nitrogen in our waters, is bigger than any particular water body. We have to think bigger, and face some contentious issues. As always, I’ll do my best to explain it all in a straightforward manner…and I’ll have pretty pictures, too! I hope you join me for the journey.

Willows, cattails, and Muskrat. Yup, that’s an Iowa wetland…

Little Sioux, Big Beauty

Ice floes on the Little Sioux

In recent weeks, I’ve been considering engineering and thermodynamics of wetland plants, nest structure design and success, ice safety, and the global carbon cycle. Seems  time to pause and simply enjoy the beauty of wetlands! This past weekend I strolled along the banks of the Little Sioux River at Washta Access in Ida County. I’ve described the dynamics of rivers and floodplains in previous posts, such as the snarled drift at Snarl Street or a Tale of the Swale here in western Iowa. So today, I’m mostly enjoying a nice walk in the woods!

It was a lovely day: sunny and unseasonably warm. There was no wind to speak of, so the woods were quiet. I found myself in a contemplative mood, and lingering here and there, enjoying the colors and textures of the ice and snow and vegetation.

Just upslope from a natural levee, I noted a tree growing straight and true, despite a long, twisting wound along its trunk. Scar tissue bordered the rotting wood, the tree adjusting to this injury and carrying on. Trees contend with such challenges, as they must, but why is this such a perfect, gradual spiral?


Spiral scar on a tree trunk

Trees have such beautiful forms and endless variety! Deciduous (hardwood) trees in winter are especially striking, with the leafless crown revealing the graceful spreading branches, the crevices and coverings on the skin, and the life incorporated on the tree’s body.

It’s easy to think of plants as “dead” in winter, but winter dormancy is more like “hitting the pause button.” A dramatic example is a twining vine caught reaching out into space, frozen (literally) from its journey growing up a little Ash (Fraxinus)  tree sapling. I’d love to come back in 2019 to see what it finally touches. It can stretch out only so far, and then its slender stem will fail to support its own weight…where will it go?

The river nearby has ice encrusted on the banks, and forms a surface on those portions of the channel separated from the current. Crystals grow on top of the ice in elaborate patterns. The black ice and dark water below show them off in high contrast. Floating pieces of ice slid past silently, gracefully. I watched for a few minutes, thinking about those pieces of frozen water heading south. When and where will they melt? I imagine this is all liquid water leaving Iowa, yet the water itself flows inexorably to the sea.

I hope you enjoy the wetlands in winter—the experience is quite different in this season, and a delight…at least when properly dressed, and walking on solid surfaces with good traction  (please be careful!!). Do you have a favorite winter walk? Why not share it in the comments!

Our Carbon, Our Wetlands, Our Future

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.

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.
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?

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

Floodplain, Reclaimed

impassableMy recent 99wetlands forays, and other travels, have been hampered by the flooding in much of Iowa. For example, two approaches to a wetland in Keokuk County were impassable, causing me inconvenience as I rerouted, followed by uncertain road conditions near the site (thankfully, it turned out all right in the end). However my frustration or disappointment means little compared to what others face: as I write this (October 14), flood warnings are posted for major rivers all over Iowa, affecting counties across the State; the Iowa Flood Center has 72 active alerts from sensors. Large cities such as the capital and largest city, Des Moines, but also Quad Cities (Iowa/Illinois), Cedar Rapids and Waterloo, Muscatine, Burlington, and Spencer are among the areas threatened by this flood event. Many families and business will be disrupted.

Then, there are the farms. The timing is unfortunate, as many fields across the State are still not harvested, and now the weather has turned cold (including widespread freeze warnings). Most farmers really should bring in the crop now. The fields are so wet in many cases that it’s too soft to run machinery for harvest. But in extreme cases, it’s not mud in the fields…it’s standing water. I imagine when the water recedes, it will leave behind damage to the soil and plant that present problems. A quick on-line search suggests that floods so late in the season are unusual, and farmers will need to proceed with caution as the grain or silage may be spoiled.

DSC_0251“But Paul,” you say. “This blog is about wetlands—what does any of that stuff have to do with wetlands?” Three things come to mind, actually.

First, much of the low-lying areas at danger of flooding, whether town or farm or other land-use, are located on an important wetland type: floodplains. In several past posts, I have taken you to floodplain wetlands. In Van Buren county, we made the hydrologic connection, seeing the surface connections between a floodplain wetland and the nearby river. In Wright County, we understood past flooding by observing snarled drift hung up in tree branches above the stream channel at Snarl Street wetlands. Not far from Des Moines in Polk County, we saw oxbows and other river-related wetlands at Chichaqua Bottoms.

DSC_0194But one of the very first wetlands I visited on this project, I revisited last week: Maskunky Marsh in Mahaska County. In my earlier visit, I explained that the marsh is in the floodplain of the South Skunk River, and is inundated through a horizontal pipe set at an appropriate elevation—a so-called “French Drain.” When the river is high, river water backs up through that pipe, and into the marsh…and therefore, areas downstream will experience less flooding.

On this quite recent visit, I saw that we were way, way past that type of flood stage. Indeed, the river was exceedingly high, and was completely reclaiming its floodplain. Roads, buildings, farm fields…all under water. The whole floodplain was a broad river channel. In such extreme flood events, the river will not be denied its floodplain.


This brings me to my second point: wetlands reduce flooding. Despite the extreme situation I just described, please remember: it can be worse. When I give talks about wetlands and flooding, I start by reminding listeners of their science lessons from childhood school days. Remember the famous hydrologic cycle (a.k.a. Water Cycle)? Yeah, that’s still a thing! Think of it this way: every drop of rain or snow falling within the borders of the State of Iowa must go somewhere. That water can basically go up, down, or sideways. Some portion of water falling from the sky, returns to the sky, through plants pumping it up (transpiration) or air lifting it up (evaporation). Only a very small amount travels down to deep groundwater (aquifers tend to recharge slowly). So, a lot of the water will flow sideways (laterally), across the land’s surface to ditches or streams or lakes or rivers; or, infiltrate only shallowly into the soil, and then emerge into a streambed or other surface water. And too much of that lateral flow means flooding.

Wetlands help reduce flooding, because water is held in soil and vegetation, and ponds up in the basin (standing water). Then, the accumulated water will slowly re-enter the air, or be more slowly released into streams and rivers.

The other big role of wetlands in flooding is indirect, through the process of climate change. This is a rather complex interaction, and I intend to discuss it in more detail in later posts. Suffice it to say, climate change can, among other things, make more extreme weather—and that will include flooding. Meanwhile, wetlands may—generally will—reduce a major driver of climate change, atmospheric carbon. For example, the carbon stored in peat—such as at Becky’s fen—is carbon NOT floating around the atmosphere, contributing to climate change. So, there’s a connection: wetlands reduce our risk from climate change. Add that to the flood reduction effects, and it’s clear that wetlands are here to help…and we need that help.

Everyone, please stay safe. Be careful with our current flood threats. And let’s work on measures to prepare for future risks. May I humbly suggest: wetlands will help us face our challenges…let’s protect, restore, and enjoy our wetlands…and help them, help us.DSC_0204

The best-smelling Fen

DSC_0041I cheerfully admit it: wetlands sometimes stink! Many is the time I have smelled an earthy, or musky, or sulfur-like odor as I walked or sloshed around a wetland. Just remember, please— such smells are normal, even beneficial. The characteristic odors are a sign of a wetland at work. In previous posts, we’ve thought about wetland chemistry, and its relationship to water movement and storage. Water carrying silts, sediments, nutrients…it enters a wetland, and is chemically transformed, as the wetland “cleans the water.” That work may not be aesthetically pleasing, however. Actually, your nose is quite attuned to smells which signal something you shouldn’t eat (like materials in a working wetland), and assign those odors as “stink,”and that’s a healthy thing too.

But at Rowley Fen, just outside the town of Rowley in Buchanan County, I was surprised to find something else entirely. Not only did the soil and water have no objectionable odor, I was actually delighted by what I smelled: a pronounced odor of mint! I looked down, and found that indeed I was walking among a thicket of mint plants!


Unlike the ferns and sedges around it, mints produce pretty little flowers with bright petals, presumably to attract insect pollinators. And oh, the aroma! The damaged stems or leaves released a pungent-yet-delightful smell of mint. The smell comes from aromatic chemicals common in the Mint Family (Lamiaceae/Labiatae). Other common characteristics are stems with sharp corners (i.e., square in cross-section) and flowers with a pronounced, and protruding, lower lip (labia means “lip”).

This particular plant is Mountain Mint, Pycnanthemum. I suspect P. virginianum although I could be convinced of P. tenuifolium if someone wants to make a case for it. A search on the internet will find useful information about propagating the plant and its value (including from a local supplier of wildflowers; no recommendation implied by the link). Notice many accounts on line about uses for the plant—food, tea, tonic, specific medicinal value. As I’ve mentioned before, plant use by humans (and cultural significance of plants) is a subject called Ethnobotany, and one I find fascinating. My students (such as those currently in my Field Botany class) enjoy learning about this, too. But I caution you: know with great certainty, the identity of a plant; use caution when considering a food or medicinal use. Even honest writers may inadvertently be passing along faulty information; or, your body may react differently than most. Be careful!

Anyway, it smelled wonderful, partly because it was a delightful surprise: most smells in the wetland are less pleasing (or, with my seasonal allergies, I don’t smell much at all…). Unexpected pleasures are often the best ones, in my experience!

DSC_0038The wetland was nestled in a little low spot, easily reached from the parking lot. A sign welcomed you and explained the basics of the ecosystem. Walking on the peat surface was fun: it had a characteristic spongy texture, riding above the groundwater. The peat mat even quakes a little, reminding me a bit of Silver Lake Fen or Becky’s Fen.

I couldn’t spend as much time at Rowley as I would’ve liked: a thunderstorm was rolling in. But I appreciated my brief visit, and would enjoy returning some time. Maybe I’ll “sniff out” some other little delights. Do you have a favorite natural smell, or place to stop and smell the…whatever? Leave a comment!