Managing manure in California
Merced, California - A partnership between agricultural leaders and UC Merced aims to help California farmers maintain the environment and the economy.
California is the nation's leading dairy state, generating $5.2 billion in milk and cream sales a year. While that keeps the state's 1.7 million dairy cows busy making milk, they also produce plenty of manure. The manure is filled with nutrients that farmers can use as fertilizer, but it also can pollute the environment.
Looking for help, a group of San Joaquin Valley agricultural leaders turned to UC Merced. Agriculturalists for Scientific Environmental Research teamed this spring with the university, which is testing sensors that could provide a high-tech solution to manure management.
Alejandro Castillo, an AFSER member and UC Cooperative Extension farm advisor in Merced, is assisting on the project. "We have to take care of the environment, especially the soil and the water," Castillo said. "It's a big issue, but I think there are solutions."
UC Merced engineering professor Tom Harmon is leading the research, which involves testing at fields next to two dairies.
"These dairies are doing quite well, but they obviously have to manage the waste problems," Harmon said.
Many dairies store manure in lagoons. The material can be used to irrigate crops that are fed to cows, but nitrogen levels are a concern - too much can degrade water quality.
Next to a dairy near the Merced River, wireless sensors measure soil moisture and temperature in an alfalfa field. UC Merced graduate student Heidi Dietrich studies the sensors to figure how best to deploy them so farmers can check real-time data from a laptop computer.
"We want to know how far down the water is going," Dietrich said. "We are trying to see if it goes into the groundwater."
Other sensors monitor soil levels of nitrate and ammonia. But these chemical sensors are finicky, labor-intensive and cost about $400 each, so the researchers are seeking simpler, less expensive alternatives.
The Merced County Community Foundation is contributing a grant of nearly $200,000 for the multiyear project. Additional funding is sought.
"We want accurate, scientific information on the impacts we are having on the environment," said Merced dairy owner Henry te Velde, who heads the group.
The research could help show how to maintain groundwater quality and use manure more beneficially, he said.
"I think everybody is going to win - farmers (and) the residents of the state," said Fred Souza, dairy industry specialist with Yosemite Farm Credit, which helped orchestrate the partnership.
The partnership will provide useful information and build ties between UC Merced and the agricultural community, Souza said.
It's a natural fit. California is the nation's leading agricultural state. And UC, founded as a land-grant institution, has a rich tradition in agricultural research that continues today. For example, in another project examining dairy impacts, UC Davis and other scientists are studying groundwater quality at dairies in Tulare and Kings counties.
Harmon, who also works with the UCLA-based Center for Embedded Networked Sensing, would like to create a digital watershed in the Central Valley to predict soil and water quality. "You could forecast that like you would the weather," Harmon said.