WARNING: HEAVY SCIENCE
Gurnell, A., W. Bertoldi, D. Corenblit. "Changing River Channels: The Roles of Hydrological Processes, Plants and Pioneer Fluvial Landforms in Humid Temperate, Mixed Load, Gravel Bed Rivers". Earth-Science Reviews 111, 129-141. Dec. 2012
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This was a pretty good paper on the types of vegetation, and under what circumstances, that can establish pioneer landforms that can stabilize river banks. The paper itself talks about four separate study areas, which muddles things a bit and makes some of the interpretations a little hard to follow (which river were they talking about again? The one in France?). It was decently written, but it still had some writing issues that I found glaring. A couple of colloquialisms, five or six awkwardly written sentences, and an entire paragraph that was completely unnecessary and should have been left on the cutting room floor.
There was some very cool info in the paper, though: It talked briefly about how river systems changed in ancient history due to the influx of new vegetation types, which is a facet of Geomorph that I've never touched on before (very cool!). Apparently rivers were a lot more braided back in the day, until vegetation started to stabilize the banks. Makes sense.
There's three figures that are extremely handy, one of which describes the zone of interaction between pioneer plant species and flood disturbance in terms of vegetation biomass, which is really just a graph of how effective plants are in relation to elevation above the channel surface at establishing new forms. Another figure shows an evolutionary model on pioneer islands, which is a pretty cool concept: A reedy type of vegetation manages to establish itself, which under flow causes sediment to be entrained behind it, eventually storing more sediment under which more vegetation can establish. It's a positive feed-back loop which eventually allows the pioneer island to be incorporated into the floodplain. Again, this stuff makes sense but it's always good to see an idealized model to explain the concept.
The third model is what brought me to the paper, and that's one about riparian species and their role in allowing in-channel alluvial benches to become established. It's still all about reedy vegetation slowing down flows for the accretion of sediment, so it just gives me something to look for when I'm in the field.
I was surprised by some of the descriptions of how vegetation can be established *after* a flood event, by portions of vegetation ranging from propagules to entire limbs that can root on landforms. I hadn't thought about sections of living vegetation being able to root itself prior to be ripped off during an event, so that was a new one on me. These folks are biogeomorphologists so I bow to their expertise but I'd still like to see that process in action. Not to believe it, but I guess just to verify my understanding of how that would work.
Oh, and *tons* of sources to back track for more papers to read. I never really understood why teachers make students try to satisfy a certain criterion for citations; whatever it takes to properly cite is what it takes to finish the paper, not a firm "no less, no more" than eight. If that means 10, fine. If that means 120, fine. Whatever it takes.
Pretty good paper overall, with lots of useful info. Just needs a good revision. 80 out of 100, with the majority of the points being dinged because of bad writing.
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