修復生態学者へのインタビュー

Presenter: My guest today is Marisol Teixeira, a restoration ecologist who has spent eleven years bringing a drained river marsh back to life. Marisol, when people hear the word restoration, they picture planting. Is that the whole story?

Marisol: Far from it. In fact, our first four years involved hardly any planting at all. What we did was remove things. We blocked the drainage ditches and let the water return. Seeds had been lying dormant in the soil for decades, and once the ground was wet again, plants that nobody had seen since my grandmother's time simply reappeared.

Presenter: That sounds almost too easy.

Marisol: It would have been, had the water been clean. But the farmland upstream was washing fertiliser into the marsh, and that favoured a few aggressive reeds, which crowded out everything else. So we negotiated with the farmers to leave a strip of rough grass along the stream banks. Nobody was forced, and most agreed once they saw that the strip also reduced soil loss from their own fields.

Presenter: How do you know the project has worked? What counts as success?

Marisol: That's the hardest question, and I'd distrust anyone who gives a quick answer. We count bird species, which have risen from nineteen to forty-three, but birds can be misleading, because they fly in from elsewhere. I'm more reassured by the insects and the water quality, which respond to what's happening on the spot. And honestly, the real test is whether it still works after a flood.

Presenter: And has it been tested?

Marisol: Two winters ago, heavy rain pushed the river over its banks. The marsh absorbed so much of the water that the village downstream stayed dry, which, frankly, did more to win over the sceptics than any report I could have written.

Presenter: Were there people who opposed it?

Marisol: Plenty, at first. Some saw it as land going to waste. What changed minds wasn't an argument. It was the walking path. Once families could come and watch herons for themselves, the project stopped being mine and became theirs.

Presenter: If you could do it again, what would you change?

Marisol: I'd have started recording people's memories sooner. We kept careful data on plants, but almost none on what local people remembered of the old marsh, and some of the best guidance came from an elderly neighbour who recalled where the water used to pool. A great deal of knowledge was lost simply because we didn't think to ask.