What is some general advise about doing work in ecologically sensitive areas? Ie River Watersheds, land adjacent to wet lands, and High bank waterfront - Area's Where there is plenty of edge and everything wants to slide towards it. In my experience small changes can lead to big effects (often negative) in these areas.
Thank you for your time in addressing every ones questions
One Permaculture principle is about valuing the marginal, and concentrating our efforts on marginal land is more important than interfering with functional ecosystems. Work within the human footprint, and stay out of the bush, as they say.
Wetland areas are down in lower areas of the watershed, and often times the place to start any restoration is in the upper watershed, slowing water and stabilizing and revegetating steep slopes. It's always interesting to me how much wetland areas are protected, yet all the land that feeds the wetland is allowed to be polluted and degraded. I think that the overemphasis on wetland protection instead of watershed protection is somewhat of a symptom of our fragmented view of nature.
There are really different strategies for various types of wetland and riparian areas in different climates. In drylands, inducing meanders in streams is a delicate operation yet if done right highly effective in increasing the surface area of land exposed to water allowing more moisture to soak in the soil and greater edge for vegetation. In wetter climates, increasing the edge in wetlands with chinampa systems creates more places for diversity of species to occur.
Overall, increasing edge between wet and dry in order to create more niches for diversity to occur is a good overall strategy that seems to be consistent in a variety of situations.