Costs of flood control

Rebecca Wodder, president of American Rivers, wrote an interesting piece in this weeks PrairieFire on the rising costs of flood control, and what some communities are doing about it. I don't know where she got her numbers from, but even after spending $123 billion in inflation adjusted federal tax dollars over the last 50 years, the annual cost of flood damage continues to rise at 2.9% per year. That's a stunning set of numbers. Forget fish habitat! Here are real costs - and we don't know how fast they will continue to rise - or what the precise effects of future climate change will be. Why do people keep building on floodplains!

Unbounded uncertainty. Levees and other engineering structures work as long as the system doesn't exceed expectations - expectations that are based on the "period of record".

Answering the dinner lady

I've been sitting in on a meeting of the Adaptive Management Working Group of the Platte River Recovery Implementation Program - they are discussing the objectives and design of the "flow piece" - the experiment to test the effects of environmental flows on the Central Platte Ecosystem. I've met with these folks before, and its a vibrant and passionately interested group of folks from many different state and federal agencies. We spent the day debating the nature of the experiment, in particular what the main objective is.

But that's not what I wanted to write about - we also had dinner at a local restaurant (Front Street Steakhouse, Ogallala - they even had a pretty good vegie burger, but get the extra mushrooms and onions) - 20 odd biologists, hydrologists and engineers descended on this fine local establishment for an excellent meal and good conversation. As the last few of us were paying our bills, the woman behind the till, asked us "What are you doing with our River?". I promptly passed the buck to Chad Smith - after all, I'm merely a consultant! Chad gave a pretty good short answer - something about planning for environmental restoration - but that wasn't quite enough for her. She had two things on her mind - getting jobs in Ogallala ("Why aren't you doing it NOW") and getting the river back from the "Hunters from Cabela's" into the hands of the farmers. At the time I wasn't quite sure what to make of that last comment about the hunters, but now I think it was her label for people that want the river to do something other than provide irrigation water.

This is the essential tradeoff - water left to go down the river is water that farmers can't use for irrigation, and hence a reduced economic output for the region. Worse, the environmental restoration will not provide the jobs that the dinner lady wanted. The program has lots of money, but much of it is going to people like me - high priced consultants to help design and monitor the restoration. Much also goes to purchasing land, paying taxes and so forth, but relatively little is going to get directly into the economy of Ogallala. I don't think the full story would make the dinner lady very happy at all.

This idea that water not used is wasted isn't limited to Ogallala. I wasn't able to attend the "Future of water for food" conference held this week in my office building, but one of my colleagues that did quoted a speaker there - "water that reaches the sea is water wasted". That's a pretty radical point of view! But as an ecologist, how do I rebut that view? And, will the dinner lady ever accept my answer?

Corn! and NEPA

While browsing other science blogs I came across a great one about insects and ... well, insects. And one of Bug_girl's reviews was of a recent article predicting impacts of corn for biofuel on ecosystem services - my only thought was "Wow - did congress have to do an EIS before they passed that law?" - they should have! When does a law become a "federal action" that requires compliance with NEPA?

One of the conclusions of that article is that decreasing diversity decreases ecosystem function. I came across another article on the diversity-function debate in last week's Nature. The authors set up > 1000 microbial communities, each with the same suite of 18 taxa of denitrifying bacteria. The key was that the communities varied in "evenness" - the extent to which the community is dominated by one or a few species. They then challenged each micro-community with a dose of nitrite, and then measured how much of the nitrite was removed 20 hours later. Communities with greater evenness performed better - and more importantly, maintained that improved performance to a greater extent when the microcosm was simulataneously challenged with increased salinity.

So, is this resilience sensu Holling and Gunderson? I think not, for a couple of reasons. First, although the functional rate decreases with decreasing evenness, all the microcosms still function to some extent; there is no "flip" to an alternative non-functioning state. The appearance of a non-linear threshold would be the ultimate cool result, but they found only smooth changes. Second, they did not examine the structure of the microbial community AFTER the perturbation. Resilience posits that resilient systems will maintain their structure during and after a perturbation - structure in this case would refer to the relative abundance of the 18 microbial taxa. It is possible that even the control communities that were not challenged would have shifted in relative abundance just because of normal competition between the microbes.

Regardless, it is a really cool experiment!

Full citations:

Douglas A. Landis, Mary M. Gardiner, Wopke van der Werf and Scott M. Swinton. 2008. Increasing corn for biofuel production reduces biocontrol services in agricultural landscapes. PNAS 105(51) 20552-20557 doi: 10.1073/pnas.0804951106

Lieven Wittebolle, Massimo Marzorati, Lieven Clement, Annalisa Balloi, Daniele Daffonchio, Kim Heylen, Paul De Vos, Willy Verstraete & Nico Boon. 2009. Initial community evenness favours functionality under selective stress. Nature 458:623-627. doi:10.1038/nature07840

Stimulating Ecosystem Services?

Last week's edition of the journal Nature (Vol 457(12):764) had an editorial titled "Natural Value" - the topic: how this might be a great time to build ecosystem services into the mainstream economy. There might be something to this - after all, the value of mainstream economic activity is shrinking, making entry into the market easier. I wish that politicians the world over read this quote:

Destroying ecosystems for short-term economic benefit is like killing the cow for its meat, when one might keep from starving by drinking its milk for years to come. Now is not the time to slaughter the cow.

In addition, the editorial calls for an increase in ecosystem monitoring, research, analysis, and (bravo!) simulation. I couldn't agree more, but as ecologists we are ill equipped to meet the immediate analytical demand that would be required to "fold ecosystem services into the budget".