• UCSB_GradPost twitter avatar
    Join Health & Wellness for a free grad yoga night on January 24 https://t.co/oNSdeo1g6u #UCSB #ucsbgradpost
    23 min 10 sec ago
  • UCSB_GradPost twitter avatar
    Countless research hours. 3 epic minutes. Registration is now open for the 2017 Grad Slam competition: https://t.co/XbVjz2ydPn #GradSlam
    1 hour 10 min ago
  • UCSB_GradPost twitter avatar
    January 25 workshop on reproducible data research https://t.co/f5zONWGj5g #UCSB #ucsbgradpost
    2 hours 1 min ago
  • AS_UCSB twitter avatar
    The A.S. Bike Shop is funded by student fees. They have everything needed to get your bike running safely and smoot… https://t.co/vQuWomtIRf
    2 hours 16 min ago
  • ucsantabarbara twitter avatar
    And the “Academy Award for the Ocean” goes to… #UCSB marine biologist and conversation ecologist Benjamin Halpern! https://t.co/DUUNTs3twk
    3 hours 15 min ago
  • UCSBgauchos twitter avatar
    .@UCSB_Baseball ranked No. 25 by D1Baseball! Gauchos open season 2/17 vs. LMU #GoGauchos https://t.co/H6HkaLG5CL
    3 hours 48 min ago
  • UCSBgauchos twitter avatar
    WBB: UCSB Finishes Three-Game Home Stand With Long Beach, Hawai'i https://t.co/lMi1wav3ic
    18 hours 27 min ago
  • UCSBgauchos twitter avatar
    WBB: Sarah Porter Named Big West Player of the Week Following Career Performance https://t.co/fr3wddBDvc
    19 hours 56 min ago

Agriculture’s Environmental Footprint

A new Bren School study shows that life cycle assessment updates are essential to quantify the environmental impacts of agriculture
Thursday, October 8, 2015 - 16:30
Santa Barbara, CA

Soybeans1.jpg

Soybean field

The freshwater ecotoxicity impact of soybean production quintupled, largely due to the soybean aphid, which required increased pesticide use.

Photo Credit: 

Tim McCabe / Photo courtesy of USDA Natural Resources Conservation Service., via Wikimedia Commons

Researchers who work in life-cycle assessment (LCA) rely heavily on databases to quantify the environmental impacts of products and services. In industries that change rapidly, such as the electronics and high-tech sectors, LCA datasets are updated frequently to ensure the most accurate analyses. However, datasets for agriculture — which is perceived as changing slowly — tend to be updated infrequently.

“People tend to think of agricultural as an industry of the past that doesn’t change much and has environmental impacts that are more or less constant over time,” said Sangwon Suh, a professor in UC Santa Barbara’s Bren School of Environmental Science & Management. “They may think that using 20-year-old LCA data is okay for agricultural products.”

In a paper published in the journal Environmental Research Letters, Suh and his co-author, Bren School alumnus Yi Yang, show that a variety of factors, including climate change and technological advances, have made agriculture in the 21st century highly dynamic.

The researchers gathered a large amount of new data for four major crops, examining 10 years of environmental impacts resulting from the cultivation of corn, cotton, soybeans and wheat. They measured acidification (air), eutrophication (water), smog formation, freshwater ecotoxicity and several human health criteria.

While several impacts remained relatively stable over time, others varied significantly. For instance, in the past decade, the per acre impact of both cotton and corn cultivation on the ecological health of freshwater systems decreased by about 60 and 50 percent, respectively. The decreases are believed to have resulted from expanded use of genetically modified crops, which require fewer pesticides and herbicides.

But the researchers also found that the freshwater ecotoxicity impact of soybean production quintupled, largely owing to the spread of the soybean aphid, an invasive species. This in turn led to increased use of insecticides.

According to Suh and Yang, understanding the factors that drive change in the environmental impacts of agricultural systems is essential for making informed decisions, prioritizing which LCA data to update more frequently and interpreting LCA results that use older data.

“Our study implies that it is worthwhile focusing on the rapidly changing categories when updating agricultural LCA databases under time and resource constraints,” Suh concluded.

Contact Info: 

James Badham
(805) 893-5049
james@bren.ucsb.edu

Topics: