Where in the World is Philadelphia?

by Dennis Burton
Posted 2/25/21

We all want to save the planet. But what does that really mean?

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Where in the World is Philadelphia?

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We all want to save the planet. But what does that really mean?

By the early 20th Century, the American wilderness was 90% conquered. Millions of forested acres, prairies, coastal ecosystems and wetlands succumbed to the axe and the plow. By the mid-20th Century, we noticed and wanted it back again.

Thankfully, the planet is resilient and humans, for better or worse, determined. To preserve what was left of nature, people in the mid-20th Century founded the World Wildlife Fund 1962, passed the Wilderness Act of 1964 and the Endangered Species Act of 1966, created the Environmental Protection Agency in 1970 and founded The Nature Conservancy in 1954. These organizations and acts began refocusing our relationship with nature. But was it too late?

Another way to ask is: Are we too far removed from nature to rejoin it? Despite the environmental groups above, as well as the National Wildlife Federation, the Audubon Society, our vast park systems, and myriad conservancies nationwide, our wild species continue to dwindle. Apparently, our conservation efforts have fallen short of our goals.

Could that mean that rather than saving and rejoining nature we’re going to lose it? Or should we reconsider our conservation strategies to date? We have dwindling populations of flora and fauna, but there is still plenty to “save,” even increase. So, some ecologists and environmentalists propose rethinking our connectivity to nature. Rather than simply preserving fragments of nature in public spaces, we should also be connecting the pieces we’ve preserved.

The ecologist’s mantra states that “Everything is connected to everything.” To that end, ecologists have divided the United States into over 100 ecoregions: epa.gov/eco-research/ecoregions. Philadelphia sits in the Northern Piedmont ecoregion between the Atlantic Coastal Plain and the Ridge and Valley regions.

Subtle geographic and biological features - soil, hydrology, topography,  plants, and animals - distinguish these overlapping systems and, prior to modern development, there was a contiguous continuity across those features. That continuity allowed plant and animal species to move easily between ecosystems and increase their range, and that expanded range gave those populations the ability to withstand environmental and predatory pressure. If the coastal plain flooded, or a forested area burned, that wide range of systems favored survival and larger populations.

But when these ecosystems become fragmented – by highways, housing developments, agriculture, infrastructure – essentially creating patches, movement between them is impeded. During a disaster, there may be no safe escape. Additionally, fragmentation alters the physical characteristics  and quality of the ecosystem, creating more edges that are hotter, drier, and windier than the interior of an intact ecosystem.

This creates conditions better suited to ecologically less functional invasive species and easier access for predators. Many resident and migratory forest birds have declined because of increased exposure to racoons, crows, blue jays, and house cats. Similarly, fragmentation affects the populations of wild mammals, amphibians, and reptiles. These population declines ultimately alter the balance of healthy ecosystems, where birds, reptiles, and amphibians keep insect populations in check, and the mammals keep the birds, reptiles and amphibians balanced.

This all has the feel of doom and gloom about it, but most restoration ecologists feel otherwise. Indeed, it’s their job to see the ecological potential in degraded landscapes and create corridors to connect the healthy remnants of ecosystems. To rebuild the pottery from the shards.

Restoration ecology focuses on reconnecting the fragments and enhancing ecological health. Accomplishing that requires cooperation between the restorers of native habitat, and the landowners who may not be aware of these issues, because over 80 percent of those fragments are on privately owned land. And, according to Douglas Tallamy’s research in “Nature’s Best Hope,” 92 percent of those fragments are covered in lawns, ecological deserts with minimal diversity.

Indeed, the turf grass in lawns covers more than 40 million acres of America’s property. And because lawns have become the dominant landscape feature for most home builders and buyers, connecting them to remnant, intact ecosystems will require a lot of local cooperation.

But let’s not end this column by disparaging lawns. Lawns do have a place in our landscapes: As sitting areas, for some recreation, buffers between our houses, and durable walking areas through our native plant gardens. Saving the planet entails more than converting turf to meadows and forest. Ecological landscape design that includes meadows, forest remnants, and turf will begin to reunite us with nature, one yard at a time, until we truly are one with nature.

The next column will begin to explore the nuts and bolts of that endeavor, even if you don’t have a lawn.

Dennis Burton is the former director of the Schuylkill Center for Environmental Education. He is a master gardener and the author of “Nature Walks of Central Park.”

Back to Nature

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