Science news & reports: Modeling the Yolo Bypass, Knaggs Ranch results, nitrogen study, Elwha River restoration and geoengineering
New hydraulic modeling software aids in Yolo Bypass floodplain restoration: The crew at UC Davis test drove a new hydraulic model developed by the Army Corps in their ongoing studies of the Yolo Bypass: ” … We’re developing an optimization model to explore when, where and how floodwaters might most economically be applied to manage all the diverse activities. The HEC flood simulation model will help us determine whether solutions from this separate optimization analysis are realistic. Would there be enough water at the right times to flood enough, but not too much of the bypass? Do the fields targeted for inundation have the channels and berms to deliver and hold water for the desired duration? If an optimal solution calls for engineered modifications to the floodplain, we can use the HEC model to test the effects of those potential changes. … ” Read more and see the model in action at the California Water Blog here: Innovations in floodplain modeling: A test-drive on the Yolo Bypass
Knaggs Ranch 2013 results now available: Speaking of the Yolo Bypass, UC Davis has posted the preliminary report prepared for the Bureau of Reclamation on the Knaggs Ranch project: ” … To better understand how management of rice fields may affect water quality, invertebrate assemblages and abundance, juvenile salmon growth, survival, and behavior, three concurrent studies were conducted in the northern portion of the Yolo Bypass on the Knaggs Ranch. The specific study elements were 1) food web and salmon responses to agricultural management; 2) behavior of salmon in different agricultural habitat types; 3) a pilot study evaluating the feasibility of extending inundation duration after natural flood events to prolong salmon rearing in floodplain habitats. … ” Read the report here: The Experimental Agricultural Floodplain Habitat Investigation at Knaggs Ranch on Yolo Bypass 2012-2013
Why do people live in floodplains? The Nature Conservancy’s Julie Morse lives in the Pacific Northwest, where precipitation is a common occurrence. With rivers reaching flood stage over 1400 times in the past 20 years, flooding is a fact of life. ” … But the thing is, I don’t get it. As a relative newcomer to the Pacific Northwest, I’ve never experienced a really bad flood. This fact precludes me from answering a common question that comes up frequently: why do people live in the floodplain? Fundamentally, this question is about science communication. After all, if we just presented people with the facts, they wouldn’t be so likely to live in a floodplain. Right? … ” Read more from the Cool Green Science blog here: The Limits of Science Communications: Why do People Live in Floodplains?
Scientists present approach for monitoring Lake Tahoe’s nearshore environment: The joint project between Desert Research Institute & UC Davis developed the comprehensive approach for assessing and managing the nearshore ecology and aesthetics of Lake Tahoe: ” … The report does not recommend changes to existing state and TRPA legal or statutory definitions or standards affecting the Lake Tahoe nearshore. Rather, for the first time in one report, it explains the unique aspects of this important zone; evaluates existing California, Nevada and TRPA standards and thresholds related to this region; presents a new conceptual model for evaluating nearshore environmental health; and proposes a monitoring strategy intended to help resource managers identify the most meaningful physical, chemical and biological indicators of healthy nearshore conditions. … ” Read more from PhysOrg here: Scientists present approach for evaluating and monitoring Lake Tahoe’s nearshore
Nitrogen persists in the environment for decades: In a 30 year study, researchers in France used an isotope ‘fingerprint’ to track fertilizer used in 1982, measuring how much nitrogen was taken up by the plants and how much remained in the soil. The results: ” … Thirty years after synthetic nitrogen (N) fertilizer had been applied to crops in 1982, about 15 per cent of the fertilizer N still remained in soil organic matter, the scientists found. After three decades, approximately 10 per cent of the fertilizer N had seeped through the soil towards the groundwater and will continue to leak in low amounts for at least another 50 years. … ” Read more from Science Daily here: Nitrogen Fertilizer Remains in Soils, Leaks Towards Groundwater for Decades
Elwha River restoration: Scientists are studying the dramatic changes happening on the Elwha River and how the fish are being impacted: ” … Dam removal began in 2011 and will connect the headwaters of the Elwha with the mouth of the river. The project is expected to be completed by 2014. One of the major challenges in removing the dams was figuring out how to deal with all the sediment stored behind the dams – enough sediment to fill 11 NFL football stadiums. To deal with the sediment, construction crews are taking the dams down gradually, piece by piece, rather than dynamiting them. Even so, the river is swollen with sediment. And the physical shape of the river is changing as the river deposits sediment along its banks. Matt Beirne, a scientist with the Lower Elwha Klallam Tribe, nets juvenile fish to study how the dam removal is impacting them. “This place is changing every day,” Duda said. “Every time I come out there’s something new, something different.” … ” Read more from Quest here: A River Returns
Geoengineering – will it save the world? The summer, the Haida people in Canada dumped a boat full of iron dust into the ocean with the hope that the resulting algal bloom would bring the salmon back. The move was described as a the world’s first ‘rogue geoengineering project’: ” … While it scared a lot of people and angered a lot of scientists, this event could be a sign of what’s to come. Some very mainstream scientists are saying the climate change situation is so bad that saving life as we know it might require something radical: like shooting chemicals into the stratosphere to protect Earth from the sun. In essence, these scientists are talking about hacking the climate. … ” Read more from NPR’s All Things Considered here: To Fix Climate Change, Scientists Turn To Hacking The Earth