Aquaculture in many countries around the world has become the biggest source of seafood for human consumption. While it alleviates the pressure on wild capture fisheries, the long-term impacts of large-scale, intensive aquaculture on natural coastal systems need to be better understood. In particular, aquaculture may alter habitat and exceed the carrying capacity of coastal marine ecosystems. In this paper, we develop a high-resolution numerical model for Sanggou Bay, one of the largest kelp and shellfish aquaculture sites in Northern China, to investigate the effects of aquaculture on nutrient transport and residence time in the bay. Drag from aquaculture is parameterized for surface infrastructure, kelp canopies, and bivalve cages. A model for dissolved inorganic nitrogen (DIN) includes transport, vertical turbulent mixing, sediment and bivalve sources, and a sink due to kelp uptake. Test cases show that, due to drag from the dense aquaculture and thus a reduction of horizontal transport, kelp production is limited because DIN from the Yellow Sea is consumed before reaching the interior of the kelp farms. Aquaculture drag also causes an increase in the nutrient residence time from an average of 5 to 10 days in the middle of Sanggou Bay, and from 25 to 40 days in the shallow inner bay. Low exchange rates and a lack of DIN uptake by kelp make these regions more susceptible to phytoplankton blooms due to high nutrient retention. The risk is further increased when DIN concentrations rise due to river inflows.
Roz Naylor, Director of the Center on Food Security and the Environment talks how technology will help meet the growing demand for food and water in the developing world and why tech companies should invest in Africa.
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Roz Naylor and Russ Altman talk the future of food security.
Large and regular seasonal price fluctuations in local grain markets appear to offer African farmers substantial inter-temporal arbitrage opportunities, but these opportunities remain largely unexploited: small-scale farmers are commonly observed to "sell low and buy high" rather than the reverse. In a field experiment in Kenya, we show that credit market imperfections limit farmers' abilities to move grain inter-temporally. Providing timely access to credit allows farmers to buy at lower prices and sell at higher prices, increasing farm revenues and generating a return on investment of 28%. To understand general equilibrium effects of these changes in behavior, we vary the density of loan offers across locations. We document significant effects of the credit intervention on seasonal price fluctuations in local grain markets, and show that these GE effects shape individual level profitability estimates. In contrast to existing experimental work, the results indicate a setting in which microcredit can improve firm profitability, and suggest that GE effects can substantially shape microcredit's effectiveness. In particular, failure to consider these GE effects could lead to underestimates of the social welfare benefits of microcredit interventions.
Pamela Ronald was a Visiting Professor at the Center on Food Security and the Environment in 2018 and remains an FSE affiliate. She is also a Distinguished Professor in the Department of Plant Pathology and the Genome Center at UC Davis and serves as Director of Grass Genetics at the Joint Bioenergy Institute in Emeryville, California and Faculty Director of the UC Davis Institute for Food and Agricultural Literacy.
Ronald’s laboratory studies the genetic basis of resistance to disease and tolerance to stress in rice. Together with her collaborators, she has engineered rice for resistance to disease and tolerance to flooding, which seriously threaten rice crops in Asia and Africa. For example, Ronald and collaborators discovered the rice XA21 immune receptor and the rice Sub1A submergence tolerance transcription factor. In 2015, five million farmers planted Sub1 rice varieties developed by breeders at the International Rice Research Institute. In 1996, she established the Genetic Resources Recognition Fund, a mechanism to recognize intellectual property contributions from less developed countries.
Please join us for a special screening of 'FOOD EVOLUTION' with a panel discussion where the film's director Scott Hamilton Kennedy and Stanford experts in the field of food security will discuss what "GMO" and "organic" mean for the health of your family and the environment. Pamela Ronald, coauthor of the book Tomorrow’s Table: Organic Farming, Genetics and the Future of Food which helped inspire the movie will also be hosting a book signing during the reception following the event.
Amidst a brutally polarized debate marked by passion, suspicion and confusion, FOOD EVOLUTION, by Academy Award®-nominated director Scott Hamilton Kennedy (The Garden, Fame High, OT: Our Town), explores the controversy surrounding GMOs and food. Traveling from Hawaiian papaya groves, to banana farms in Uganda to the cornfields of Iowa, the film, narrated by esteemed science communicator Neil deGrasse Tyson, wrestles with the emotions and the science driving one of the most heated arguments of our time.
In the GMO debate, both pro and anti camps claim science is on their side. Who’s right? FOOD EVOLUTION shows how easily misinformation, confusion and fear can overwhelm objective analysis. How do we ensure that our food supply is safe, and that everyone has enough to eat? How do we feed the world while also protecting the planet? Has genetic engineering increased or decreased pesticide use? Are GMO foods bad for your health? And, most importantly, what data, evidence and sources are we using to approach these important questions?
While the passionate advocates in the film are all concerned with the stewardship of safe, nutritious food for the planet, their differing views over what constitutes the truth have pit them against each other, rendering the very subject of food itself into an ideological battleground.
Enlisting experts such as Mark Lynas, Michael Pollan, Alison Van Eenennaam, Jeffrey Smith, Andrew Kimbrell, Vandana Shiva, Robert Fraley, Marion Nestle and Bill Nye, as well as farmers and scientists from around the world, this bold and necessary documentary separates the hype and emotion from the science and data to unravel the debate around food, and help audiences reach their own conclusions. In a debate in which all sides claim to be on the side of science, FOOD EVOLUTION brings a fresh perspective to one of the most critical issues facing global society today.
PANEL
Scott Hamilton Kennedy, FOOD EVOLUTION Director/Academy Award® nominee, writer, director, producer, cameraman, and editor
Ertharin Cousin, Payne Distinguished Lecturer, Freeman Spogli Institute for International Studies/Visiting Fellow, Center on Food Security and the Environment/Distinguished Fellow of Global Agriculture, Chicago Council on Global Affairs/Former Executive Director, World Food Programme
Pamela Ronald, Visiting Professor, Center on Food Security and the Environment/Distinguished Professor, Plant Pathology and the Genome Center, UC Davis/ Director, UC Davis Institute for Food and Agricultural Literacy/co-author “Tomorrow’s Table: Organic Farming, Genetics and the Future of Food"
MODERATOR
Rosamond Naylor, Gloria and Richard Kushel Director of the Center on Food Security and the Environment, William Wrigley Professor of Earth System Science, Senior Fellow, Stanford Woods Institute and Freeman Spogli Institute for International Studies
