Of the ecosystems present in the United States, wetlands represent one of the most endangered. Since European settlement in the 18th century, over one-half of the wetlands in the lower 48 states has been lost.
The result is a reduction in the benefits that they provide. Vulnerability to floods increases without their ability to absorb excess floodwaters. Shorelines are more susceptible to erosion without the buffering action they supply. In addition, every time a wetland is disturbed the risk for unleashing toxins trapped in the sediment rises.
The benefits that these ecosystems provide are well-documented, hence, the system of mitigation that is practiced routinely. For wetlands lost to development, additional wetlands are created in another area. However, a study published in the January 24, 2012 issue of PLoS Biology warns that this may not be enough.
Researchers analyzed the health of restored wetlands based on biodiversity and soils. What they discovered is sobering evidence that these habitats never fully recover, even after 100 years when compared to natural wetlands. The study documented an average loss of 25 percent of productivity.
The study also noted a deficiency of organic matter. The soils of wetlands build up over time, accumulating nutrients and other materials that contribute to the health of these habitats. Researchers found that in some areas the accumulation barely reached 50 percent after 55 years.
These findings combined with the environmental and economic benefits of wetlands point to an obvious conclusion. The viability of these ecosystems depends upon them not being disturbed. In other words, mitigation is not a definitive answer for stemming these effects.
Researchers concluded that a more sound approach may be preservation rather than mitigation. The component that restoration cannot provide is time. It cannot replace the effects of being in an undisturbed state.
An increase in education and awareness is needed to understand the values and needs of these ecosystems. From an environmental perspective, most commercial and game fish rely on these habitats, as well as over one-third of the nation’s threatened and endangered species.
These facts and their role in flood protection link them resolvedly to the health of the planet. For this reason, wetland ecosystems deserve greater protection and respect.
