Gnamma #79 - The Case Of The Disappearing Marsh

Conservation is rife with sob stories over the tragedies of losing unique landscapes or the things they contain. The arguments for protection or conservation may be purely emotional, ethically-motivated, tools for social equity, or even utilitarian in some long-winded logic about how biodiversity benefits us all through the gaia mechanisms. Landscapes that have been instrumentalized into production of some way pit the macroeconomic-utilitarian versus the conservationist. I'm generalizing here, but I think you know the  prototypical story: birders write nasty letters against a plot of land turning into agricultural fields, rare plant enthusiasts protest the opening of a new mine, John Muir fighting US Congress' decision of "[water] management over aesthetics" in Yosemite's Hetch-Hetchy valley. 

As awareness, theory, and technical capability have grown for "nature-based solutions" to climate change, the prospect grows for overlap and collaboration between these two "factions"—the utilitarians and conservationists—working in harmony at site-based scales. One of the arguments to promote the creation and use of carbon and ecosystem credits is that they're a method to produce market-based financial assets out of conserved land and conservation-minded management, making money off the land without needing to raze it. I've become interested in this particularly through an example of tidal marshland that I'm familiar with inside San Francisco BayI'd like to dive into an example of a coastal marshland that I'm familiar with in San Francisco Bay, Whale's Tail Marsh. 

Long seen as "junk" landscapes, marshes around San Francisco Bay were initially used as dumps or places for low-grade or dangerous work (read: explosives) under colonization, and that's before they were filled-in with dredged sediment to pave them over and build the office parks of Silicon Valley. Originally viewed of as nearly free for "land reclamation," the financial value per square meter of former marshlands has increased as offices, shops, and apartments have appeared over them, tempered a bit by their remoteness, and increasing awareness of the geotechnical difficulty of building over flood-prone soil that easily liquefies under the frequent Bay Area earthquakes. Historically, many marshes in South San Francisco Bay were turned into shallow ponds for harvesting salt, a practice that went comparatively insolvent decades ago, yet the odd-colored brine ponds persist and are still visible as you land at SFO by plane. Thanks to purchases by the state and easements, many of those salt ponds are now slated to be restored back into marshlands through fairly typical conservation mechanisms. Whale's Tail Marsh was never entirely turned into salt ponds or agricultural land, making it one of few "historic" marshes around SF Bay. This is important because quality research has shown that thus-unmodified land should be kept as-is with priority, as pre-established landscapes tend to perform better than restoration zones. Their long-established ecologies and soils have much more certainty in them, w.r.t. ecosystem services, than restoration projects and thus should be prioritized. (Reminder that the contemporary conception of environmental "restoration" is only a few decades old!) 

The conservationist increasingly has tools to give economic value to the remaining slivers of marshland in SF Bay by way of selling their ecosystem services. California—or private owners—may want this money to invest in marsh protection, infrastructure, or monitoring, in addition to covering the construction costs needed to continue the process of turning salt ponds back into marshlands. Marshes are excellent landscapes for rapid carbon removal as they receive lots of sediment from upland and bury vegetation under sediment and water, effectively sequestering the carbon therein. Marshes clean water and are hotspots for nutrient cycling, thereby supporting populations of lots of animals, including fish and bird populations that interplay with regional and ocean-wide food chains. Marshes can also act as buffers against coastal flooding, and can help accommodate extra stormwater during rain events (although this particular facet is less relevant, or at least less-studied, in California). Through the lens of carbon and ecosystem service credits, all of these functions can be assigned financial values. 

All credits I've seen require a property called "additionality". This requires that the intended function and change in the system would not happen were it not for the intervention that issues the credit and the sale of that credit. In other words: you can't just get carbon credits for having a marsh sitting around and doing its thing; you have to have implemented some change (either as a specific project or management shift) that promotes an ecosystem service and then sell the credit that is pegged to the marginal change in the service. The sale of the credit needs to have incentivized the increase in the service. 

This is an excellent requirement (though often very difficult to demonstrate causally) in the logic of carbon offsets, where a company purchases a credit to "offset" the new production of something. Their new production gets "balanced out" with some additional ecosystem service, via the market exchange of the two. Exchange in this way would work easily if, say, carbon sequestration was done as a cube you could pop out of a machine—or something close to it—but when actually done by landscape systems,  which typically operate slowly and in patches, the accounting gets to be more complicated. 

The essence of additionality puts primacy on the "intervention" and what follows from it rather than the ecosystem services of the yet-modified landscape. The need to change and modify the landscape in order to generate a token of financial value carries, to me, a "do-more" pro-growth affect in a world that needs more badly a degrowth mindset (or maybe do-nothing technique). And to the degree that we understand the physical science of these systems, a degrowth/non-interventionist approach keeps us more in the realm of the "known unknown" of how holistic landscapes and ecologies function, conservatively distanced from the "unknown unknown" of how "restored" landscapes behave. I'm not anti-additionality as a principle, but I am ideologically against depending on systems that hold landscapes accountable to economics-based expectations of how they should function, as they are complex systems that tend to exist as assemblages across many spatiotemporal scales and entities, intertwined with the world beyond just the "landscape unit" of the owned parcel. Here's a Fukuoka quote found by my friend Nate to tie off this epistemological thought: 

Additionality-centric ecosystem service credits seem like a setup for failure, with incentives to decouple the abstract credit asset from the actual behavior of the earth surface. 

A science-focused approach to ecosystem credits would like for the asset and its parcel of land to be well-coupled. Even in a world without additionality requirements, the financial assessments of ecosystem services will be intertwined with the projected futures of the parcel of land. I bring up Whale's Tail Marsh because it is eroding rapidly. One of the chapters of my dissertation is about the details of how exactly, but the gist is that the shoreline edge of the marsh is retreating landwards at close to 2 meters per year—an amount noticeable to a casual, quarterly birdwatcher. My research points to the erosion being a natural process, part of a geologic-time expansion and contraction of marshes due to shoreline change but it has likely been accelerated by rate of sea level rise and limited sediment in SF Bay from water management infrastructure in California.  Often when a marsh retreats, it moves upland—but there is a freeway and development in the way in the case of Whale's Tail, and as in many urban marshlands. So all it can do is shrink. As it shrinks in area, the marsh' ability to provide ecosystem services accordingly vanishes in nonlinear ways. Any strong-armed intervention to prevent erosion (which are being tested near Whale's Tail by the Army Corps of Engineers) will be experimental, with big uncertainties on the potential outcomes. The uncertainty in the trajectory of the site is layered on top of "heroic assumptions" and "huge error bars" of evaluation of the ecosystem services it provides. Meanwhile, by shrinking, the carbon previously stored in the sediments is re-mobilized and can enter the ocean and atmosphere.

After all this: is it worthwhile to try to protect or "restore" Whale's Tail Marsh? Is it worth it in ecosystem credits alone or in total dollar value? SF Bay marsh sediments typically have a low proportion organic material so  by eroding Whale's Tail Marsh (only 0.75 square kilometers big), the system is releasing about 150 metric tons of carbon per year, on top of the more difficult-to-quantify services such as biodiversity support, flood protection, and water purification. If this erosion was prevented—or even reversed—our additionality calculation would need to account for how long the emitted carbon would have stayed in the atmosphere, the life-cycle emissions of all of the construction materials and equipment use, and new projections of how long the intervention and temporarily-protected marsh will remain. How much water would have been cleaned, how many birds would have nested. You can even bring in a carbon-unit discounting rate, though I agree with this piece that discounting carbon storage leads to some unrealistic expectations and if anything, a little less abstraction in this space would help. Still, all this budgeting is doable, but I haven't introduced the financial valuations yet of the credits and other ecosystem services and unfortunately, the math doesn't get any simpler. The consideration of the trajectory and future function of the marsh raise questions of time-specified financial instruments and the expected timeline to get a return-on-investment of any given project. 

If this post has one core message, it's this: the production of effective ecosystem credits depends on how exactly you do the complicated, assumption-riddled life-cycle analysis SLASH benefit-cost analysis of the site and any actions. Carbon is relatively simple as an ecosystem service, even! And after that, you can deal with the complexity of making those financial assets fund positive environmental change. I squarely believe—and this paper agrees—that the precise valuation of environmental services should not be the focus of our attention, but rather a tool towards effective landscape function and politically-defined ecological goals.  Through this clutter, it is likely that big-scale, functionally and conceptually simple projects will dominate ecosystem credit markets, as the impressionistic (i.e. vague & imprecise if not entirely limited and unstable) nature of ecosystem service quantification has room to breathe with big regions in which bulk-level quantification will perform better. Maintenance costs may also benefit from scale, and minor changes in the landscape—some erosion, for example—may be balanced out by expansion elsewhere. The domination of large-scale projects in climate markets may do what we need to, purely from a greenhouse-gas-emissions perspective, but we will lose out on many small, complex sites like Whale's Tail Marsh and the potential to provide economic support for small players. Patchworks of small sites are often all that urbanized areas have for ecosystem function. Action or inaction at small-site scales will have complicated interactions with other systems too: this paper suggests shoreline modification in one portion of San Francisco Bay without coordination may lead to greater damage elsewhere, for example. Because of the difficult (and beautiful) intertwined nature of earth science, the utilitarian and conservationist may not end up as friends after all.  

I'm left feeling frustrated about many efforts whose stated goals are around environmental protection. What do we do from here? I would firstly love to see more consideration and examples of what ecosystem credits and could look without required additionality: outside of the logic of the "offset," how can we financially support land being more-or-less left alone? Land banks of various sizes may be an alternative, specifically developed for stewardship of the land, but depend on a pre-existing endowment rather than having any asset to sell in an ongoing fashion. 

In the direction of land endowments, there is a very interesting and long-standing  example, by ecosystem credit markets standards at least (1990s), called Wetland Mitigation Banking. It's only in the United States but I am curious if similar policy exists elsewhere. Initially created under the 1972 Clean Water Act, it is a mechanism which requires a "no net loss" of wetlands in a geographically-proximate way. (By development, at least: plenty of marshes are still pseudo-naturally gradually eroding). This policy has many flaws of its own, which I am writing about in my next newsletter, but it does serve as an addle to ongoing development without the need for complicated quantitative mechanism-based ecosystem service credits and open-marketplace price-setting. Wetland Mitigation Banking shows potential for more apples-to-apples tradeoff analysis as land use decisions are made, and for incentivizing densification over land that is already developed, but it remains embedded in an instrumentalizing epistemology of how the earth behaves. 

Financial options to slow Whale's Tail Marsh' erosion run slim; its future may ultimately hinge on some experimental funds from the Army Corps of Engineers, out of scientific curiosity. Because it is eroding, it's a poor investment for carbon credit cowboys, and tough to fund through infrastructure funds given its size and history. Still, the birds, mice, and subterranean critters are out there enjoying it, occasionally some birdwatchers  and scientists like me too. Whether that's enough depends on who you hire as an accountant. 

The research fueling this piece (and two more forthcoming) was provided by a grant by the Regen Foundation. Thanks to them, especially Tica, for the support through my long process of stewing. Thanks to interviews with Kelly Leilani Main and Bodie Cabiyo for their help pulling some of these ideas apart. More thanks to Dr Lara Kueppers' "Nature-Based Climate Solutions" class at UC Berkeley and many conversations with friends. 

With nature, 
Lukas