I am an advocate of promoting the benefits we get from ecosystems. But do we risk overstating the values/benefits from them? Or do we know enough about the provision of the benefit?
The 2004 Indian Ocean tsunami certainly raised the spectre of mangroves protecting coasts, but not everyone agreed on how much was provided. Alongi 2008 provided a comment on this and noted that we needed to be cautious when looking at this - see Estuarine, Coastal and Shelf Science, 76 (1), 1-13.
Another example is the expectation that replanted riparian zones will reduce diffuse nutrient input to rivers. The results may not concur with the expectation, or may be different for different nutrients, or vary seasonally. From first principles I think some of the expectations were just too high, and have not been surprised at some of the outcomes that have disappointed some pundits, as well as local people who were convinced to "buy" into such projects.
We need good examples, not half-stated examples, and we need good evidence, not just of the benefits, but of the basis for the benefits. And keeping in mind that we are tallking about the entire ecosystem when looking at these, not just an individual component. Take fisheries as an example - do we need to sustain the fish that is actually fished, or also the fish that are not fished? Or also the flows that supported the fish? And how do we cope with variable flows (besides bulding dams)? For coastal storm protection, its not just the mangrove or marsh species, but also the landform, and processes that shape these. And then we have the big ones that can reshape the entire coastal zone, and reset the successional pathways.
In otherwords, its the ecosystem and its variability that is important ..... makes sense given that we are talking about ecosystem services. Hence a call for more ecosystem-science to underpin the expectations as well as the benefical outcomes. The economic valuations may mean very little if the ecosystem does not play the game and provide the service, or if it resets itself.
I am an advocate of promoting the benefits we get from ecosystems. But do we risk overstating the values/benefits from them? Or do we know enough about the provision of the benefit?
The 2004 Indian Ocean tsunami certainly raised the spectre of mangroves protecting coasts, but not everyone agreed on how much was provided. Alongi 2008 provided a comment on this and noted that we needed to be cautious when looking at this - see Estuarine, Coastal and Shelf Science, 76 (1), 1-13.
Another example is the expectation that replanted riparian zones will reduce diffuse nutrient input to rivers. The results may not concur with the expectation, or may be different for different nutrients, or vary seasonally. From first principles I think some of the expectations were just too high, and have not been surprised at some of the outcomes that have disappointed some pundits, as well as local people who were convinced to "buy" into such projects.
We need good examples, not half-stated examples, and we need good evidence, not just of the benefits, but of the basis for the benefits. And keeping in mind that we are tallking about the entire ecosystem when looking at these, not just an individual component. Take fisheries as an example - do we need to sustain the fish that is actually fished, or also the fish that are not fished? Or also the flows that supported the fish? And how do we cope with variable flows (besides bulding dams)? For coastal storm protection, its not just the mangrove or marsh species, but also the landform, and processes that shape these. And then we have the big ones that can reshape the entire coastal zone, and reset the successional pathways.
In otherwords, its the ecosystem and its variability that is important ..... makes sense given that we are talking about ecosystem services. Hence a call for more ecosystem-science to underpin the expectations as well as the benefical outcomes. The economic valuations may mean very little if the ecosystem does not play the game and provide the service, or if it resets itself.