Williams ID’s Hot Moments in Cool Watershed
Sources: Ken Williams, Dan Hawkes, David Gilbert
The first week of 2015 saw the release of the second of three ESD video productions related to the U.S. Department of Energy–Biological and Environmental Research (DOE–BER) Genome-to-Watershed Scientific Focus Area (SFA) 2.0 project. This video describes the importance of watersheds—and in particular headwater catchments—in regulating both the quantity and quality of water flowing to downstream users.
Narrated by ESD’s Environmental Remediation and Water Resources Program Lead Ken Williams, this video, entitled “SFA 2.0—Watershed Structure and Controls,” explains the importance of a watershed—an ensemble of vegetation, land-surface terrain, and subsurface compartments from and through which rivers drain. Or as Williams puts it, “a geographic unit through which water is migrating and interacting with the soil and sediment fabric” and their associated microbial communities. The project seeks to understand how downstream users are impacted by upstream watershed processes that can have broad implications for water use decision-making, as it relates to domestic, agricultural, and industrial (including energy production) usage. Such an understanding is critically important in light of climate-induced changes in hydrology that affect the timing, magnitude and form of precipitation that serves to sustain stream flow and groundwater recharge.
Given that Williams and those involved in the project are focused on an archetypal high-elevation watershed in central Colorado, they believe that their findings will be broadly relevant not just for the greater Colorado River Basin, but for basins throughout the U.S. and worldwide.
As Williams explains, one way of approaching this study is to focus simultaneously on watershed regions (so-called hotspots) that exert primary control on the flow and processing of nutrients within these systems, and on periods of time (so-called hot moments) when an outsized fraction of the processing and activity occurs. “The journey of a packet of water through the watershed and its interaction with these hot spots during these periods of hot moment activity constitutes a fascinating journey, from the point of infiltration, migration through the soil zone, interaction with the sediment fabric, and finally discharge into the river.”
Infiltration waters pick up nutrients and elements critically important for life—carbon, nitrogen, sulfur, phosphorus and other micronutrients—and this leached material, brought in through passage through the soil zone and sediments, then begins to interact with microbial communities having the ability to modify those elements by affecting their availability to other organisms in ways that are both positive and detrimental to the greater ecosystem.
Using next-generation computer modeling approaches, the project seeks to link fluid flow and transport within the watershed to information encoded in genetic material that describes the full catalogue of nutrient cycling pathways present within the ecosystem—ESD’s Genome-to-Watershed approach. As Williams says, “Once we understand the relationship between the subsurface microbial communities and the functionality that they can catalyze, we can begin to make use of the power of models. The power of models in this context is to make predictions about how climate-induced changes in hydrology may impact the functionality and the processing of elements and their ultimate delivery to the river system. Knowing what factors, particularly in the face of climate change, may impact the reliable delivery and appropriate quality of the water, is at the heart of the studies that Berkeley Lab is pursuing.”
Watch the video:
Watch the introductory/overview Genomes-to-Watershed video, narrated by ESD Director Susan Hubbard (and also made by Ivan Berry)
To read about the first ESD SFA video, go to http://earthsciences.typepad.com/blog/2014/12/predicting-subsurface-processes-from-genomes-to-watershed-scales.html
To read further about the Genomes-to-Watershed project and recent publications, visit the SFA 2.0 website: http://esd.lbl.gov/research/projects/sustainable_systems/
Additional information about the project is provided through the following links: