Professor Os Schmitz, Professor of Population and Community Ecology, School of Forestry and Environmental Studies, Yale University, argues that most polluted ecosystems can be restored within a generation with sustained effort.
In recent research conducted with Holly Jones, Schmitz discovers that logging, agriculture, and multiple types of damages (for example, pollution, climate change and logging happening all at once) are the hardest types of damage for ecosystems to get over. Human-caused damages, such as farming or logging, may also be harder to repair than natural causes such as hurricanes or cyclones. However, sustained restoration efforts by communities can speed recovery. Schmitz says: “For example, a hurricane will knock trees down, but there’ll be still the understory and the seed bank. A hurricane creates a light gap but it doesn’t transform the land. The light gap allows the seed bank to sprout. That’s why you can get a speedier recovery after a natural disaster like a hurricane than you can after agriculture. When people have transformed the land base into one kind of use and they want to revert it back to another kind of use, they have to actively help nature along a little bit if they want it to happen quickly. They can also help by restoring the plant species that were originally indigenous to those areas.”
Schmitz argues that viewing urban areas as having their own ecology is useful, and restoring natural habitat in urban areas should be a major focus: “That’s probably one of the biggest growth areas for restoration, and I think it’s critically important to do these kinds of things, because it kindles a sense of connection to nature among urban people. It’s really important to get them to think that they’re part of an ecosystem — be it an urban or other ecosystem– rather than simply be drivers of ecosystems. When we restore parks, or when we think about creating green spaces, we have to be careful and get our values in order and identify collectively what it is that we mean by green space. For example, I can imagine that we could restore shrub lands in cityscapes. We could also have small forests throughout cityscapes.”
One of Professor Schmitz’s most powerful arguments: Nature often does a better job of protecting human settlements against natural disasters like hurricanes than any built environment. As a result, restoring nature in urban areas not only has its own reward, but also helps mitigate the effects of climate change, and is a crucial adaptation strategy. “Thinking about urban systems as ecosystems that require green spaces to be healthy and functioning is a useful way to go forward, I think. A good example is New Orleans: The mangroves that used to grow there were excellent buffers for hurricanes before there was much settlement. These mangroves were a highly cost-effective way of controlling hurricane damage. When those were removed and the wetlands were removed and the dikes were put in their place, the human built environment became less resilient. The mini-experiment that sort of proved this was a year after Hurricane Katrina hit New Orleans, there was another hurricane of I believe close to or equal in magnitude to Katrina that hit the Yucatan in a tourist area. The people in the Yucatan were really worried that the hurricane was going to destroy a lot of the hotels. But, they still have their mangroves in place. They still had those marshlands in place. These features acted as terrific buffers against that hurricane. The resort areas were spared a lot of damage because nature helped buffer the winds and the tidal surge. Here’s an example of where nature provides an important service to humankind.”
Professor Schmitz argues that it shouldn’t be nature vs. the built environment. Natural systems should be restored, or, in the case of urban areas, re-incorporated, when it’s most efficient and beneficial to do so. Once people recognize the enormous value of ecosystem services, they may then invest more in restoring damaged ecosystems. “It isn’t about fighting nature and getting rid of nature in favor of built environments. It’s the idea that nature can be beneficial to us. The message of our paper is that if we want to think about nature that way, we need to restore. We can be successful in a lot of cases, and in a good many cases we can be quite successful within the time span of a human generation or less.”