Breath of Clarity

Definition of Wetlands

1. The textbook states “Wetlands are seldom self sustaining systems.” They interact intermittently with neighboring ecosystems (aquatic or terrestrial). Can you think of an ecosystem with distinct boundaries? Discuss an example of the interaction of wetlands with their adjacent ecosystems from places you have visited.

In Ciudad Matamoros in Tamaulipas, Mexico, I would emphasize the need to maintain the saltgrass marsh between the small coastal city and the ocean. Although the saltgrass marsh and ocean are adjacent to each other, there is still a distinction between the two that creates a boundary. In the face of rising sea levels, saltgrass ecosystems crucially help with sediment accretion and stabilization which is useful for controlling erosion from increasingly large waves. Also, the saltgrass in the marsh would maintain nursery habitats. However, the sediment forming the barriers of the marsh could also be destroyed by the power of the ocean waves. At the same time, the wetland can adapt to low oxygen levels. However, it would still be impacted by the change in hydrology due to rising sea levels.

2. What is the connection of “Ducks Unlimited” to wetlands?

Ducks Unlimited is a private organization that conducts wetland management. The organization takes wetland restoration action by implementing scientific knowledge while taking legal, institutional and economic factors into account (Mitsch and Gosselink 2015, 22). The work Ducks Unlimited does is increasingly crucial as wetland regulation aims to reverse the historical trend of wetland losses in the midst of continuing draining or encroachment due to agricultural enterprises and urban expansion (Mitsch and Gosselink 2015, 22). Specifically, Ducks Unlimited protects the wetland by purchasing thousands of hectares throughout the United States (Mitsch and Gosselink 2015, 22). The organization highlights waterfowl value and contributes to a widespread effort of having no net loss of wetlands.

3. Why do you think there is so much confusion and controversy over the definition of a wetland?

There is so much confusion and controversy over a wetland’s definition because it provides multiple uses by a variety of stakeholders and therefore holds a wide array of value types. In the Carboniferous period, swampy ecosystems produced many of the fossil fuels that humans are not reliant upon (Mitsch and Gosselink 2015, 1). However, for example, the Okavango Delta in Botswana is a natural resource gem of Africa, and sustaining this wetland for tourists has been crucial in that country since the 1960s (Mitsch and Gosselink 2015, 13). Recently speaking, wetlands are regarded as valuable sources, sinks, and transformers of chemical, biological and genetic materials (Mitsch and Gosselink 2015, 1). Not to mention, domestic wetlands such as rice paddies feed approximately 50% of the world’s population while other materials, such as mud from marshes and timber from mangroves, are harvested for construction projects (Mitsch and Gosselink 2015, 9 and 11). The diverse set of functions leads to confusion and controversy over the definition of a wetland because those who support certain uses may advocate for definitions that are conducive to their interests. Additionally, particular wetland definitions are needed for two distinct interest groups: 1) wetland scientists and 2) wetland managers (Mitsch and Gosselink 2015, 36). The scientist seeks a flexible yet rigorous definition that guides its research while the manager is concerned with regulations designed to control wetland modification and therefore needs clear, legally-binding definitions (Mitsch and Gosselink 2015, 36). As a result, multiple definitions have evolved for the two types of groups which has led to confusion and controversy over the wetland definition.

Moreover, a wetland is difficult to define because of the range of hydrologic conditions as well as the great variation in size and location (Mitsch and Gosselink 2015, 27). Amount of flooding is an additional variable that makes the definition controversial because some categorizations include seasonally flooded bottomland hardwood forests, while others exclude them due to being dry for the majority of the year (Mitsch and Gosselink 2015, 32). Specifically, the definition issue emerges at the edges of wetlands, toward either wetter or drier conditions (Mitsch and Gosselink 2015, 32). Also, wetlands have unique characteristics that are not depicted by existing ecological orientations such as limnology, estuarine ecology, and terrestrial ecology (Mitsch and Gosselink 2015, 17). Some of the characteristics include, anoxic conditions, plant and animal adaptation, as well as standing water or waterlogged soils (Mitsch and Gosselink 2015, 17). Since a wetland is a transition zone between terrestrial and aquatic systems, the definition cannot fall under the umbrella of the former or the latter.


Mitsch, William J. and James G. Gosselink. 2015. Wetlands. 5th ed: John Wiley and Sons, Inc.

Comment by Carmen Valencia:

Mary, your answer for the third question brought up points I hadn’t thought of, such as the different definitions based on their necessity for wetland scientists and wetland managers. As someone who has conducted scientific research, I understand the importance of defining the terms in order to be as specific as possible for the audience, peers, and other researchers. In addition, the value placed on the wetland also has a large influence on its management, as you mentioned the tourism and monetary values play important roles in defining the wetlands. It’s very interesting what a range of ecosystems can be considered wetlands, so many attributes can be applied to create completely unique environments!

Comment by Professor Flanagan:

Hi Mary and Carmen,

Great points! You nailed it when you said “The diverse set of functions leads to confusion and controversy over the definition of a wetland because those who support certain uses may advocate for definitions that are conducive to their interests.” We see that today as federal protections change to either support the ecosystem or support developers. A simple rule change can cause to destruction of a whole category of wetlands. We just saw that with the last administration.

Trump Administration Rolling Back Federal Water Protections : NPR

My Reply:

Hi Dr. Flanagan,

Thanks for the piece from NPR! I found it particularly interesting that confusion and controversy over the definition of a wetland based upon diverse stakeholder interests brings along a disregard for science. The piece illustrated that a decision based upon interests is a quite opposite fuel from a decision grounded in science because the former is subjective and the latter is objective. Specifically, the authors mentioned that reducing the amount of wetland protection under the Clean Water Act is supported by farmers, builders and mining companies but is opposed by science advisers. In order for wetlands to be thoroughly protected, it is crucial that the role of science is seen as a tool that helps people understand all that is objectively best for them as opposed to science being a player in the pool of interests. At the end, the authors made a great point that it is quite dangerous for subjective interests to override. scientific data. For examples. they brought up pollution in the Rio Grande that is a system providing drinking water to 300,00 New Mexicans. Then, the authors went into the issue of state jurisdiction versus federal regulation. The former makes room for subjective decisions based on interests. Specifically, rolling back federal regulation that came as a result of high regard for scientific data about pollution in wetlands is essentially paving the way for interests to steer the wheel. While advocates of business interests depict broad federal regulation as a massive power overreach by the government, having a lack of federal regulation essentially leads to a massive power overreach that is not grounded in science. When Texas Attorney General Ken Paxton criticized Obama’s executive action as too broad, he failed to recognize that all of the wetlands are being considered waters of the United States because of the scientific findings regarding the benefits that all of the wetlands have in common. The revised rule excludes some wetlands from the grouping even though they all still provide the benefits included in the definition. So, a new definition based on interests is destroying a whole category of wetlands proven to be valuable by the scientific definition.

My Reply to Carmen:


Phenomenal point that precision in term definitions is so important. The wetlands definition shows that precision does not necessarily include making a definition more narrow or exclusive. It supports scientists in gathering accurate data. From there, scientists can still be fine-tuned while comparing the wetlands across a variety of types and locations. It goes to show that even a precise definition of wetlands can still encompass such a variety of unique environments. The wide array of ecosystems that can be considered wetlands is particularly remarkable because they all provide the benefits outlined in the wetlands definition. Of course, a greater value placed on wetlands leads to people allocating a higher amount of resources to manage it. In addition to tourism and monetary values, communicating the biological values of wetlands is a key step to preserving them. That is where Ducks Unlimited comes into play as it highlights waterfowl value as part of its effort to generate funds to purchase wetlands throughout the United States.