So much mud and sediment were pouring into Mobile Bay in the 1970s that their grimy plume was captured in images taken by NASA's Skylab space station as it orbited the Earth. The heaviest mud, oozing out of Daphne, traced to the construction of the giant Lake Forest subdivision. (U.S. Geological Survey film archive collection)

We must protect the edges

If you were to study Alabama's diversity -- from carnivorous pitcher plants and delicate orchids, to the dozens of oak species or the nation's most diverse assemblage of aquatic creatures -- there is one constant: Almost all of your research would occur within sight of water.

The water might not amount to much more than a puddle in a soggy bog, or the small, ephemeral springs weeping from a hillside in a lush oak and magnolia forest, but wherever you are, there will be water. From the rocky rills at the top of the state to the cypress swamps and blackwater streams on the coast, that water is the reason that Alabama has more than twice as many species per square mile as any other state on the continent.

When we talk about the edges, we are talking about the places where the land and water meet, along our rivers, creeks, bays and beaches. The zones straddling wet and dry are biological hotspots, providing the just right mix of water and habitat required by so many of our rare organisms.

The problem is that this meeting zone is often where people want to be. We build our houses along the river to enjoy the scenery. Farmers water cattle in the creeks. Industry wants to site factories beside the floodplain, so their wastes can be diluted in the river and washed away with minimal treatment. The challenge is to find a way to accommodate people's needs and desires, while protecting the water quality that nature requires.

"We have done an incredible job of protecting about 100,000 acres of the Delta. That is just a remarkable thing," said Bill Finch, science adviser at the Mobile Botanical Gardens, discussing the purchase of the wettest, swampiest part of the Mobile Basin, the Delta lands subjected to the annual flooding. Even so, that land essentially protects itself from encroachment, because it's impossible to build on swamp mud that's under water for five months of the year.

"There was nobody spending a lot of money developing the Delta, so that land came cheap. It's great that it is now public access," Finch said.

Much harder to purchase, according to Finch, are the places where people have good views and can put up a house. "We have done a miserable job of protecting those areas and that is the great challenge. I'll say it for the 15th time, if we don't protect those edges, we have lost the Delta. We have lost the Delta."