Water risks threaten agriculture
Recently, the Environmental Defense Fund (EDF) published a document entitled “Scarcity and Excess: Tackling Water-Related Risks to Agriculture in the U.S.,” which notes the nation’s agriculture industry is at risk from climatic extremes and groundwater over extraction.
“Water is essential for growing the food and fiber society depends on. Water availability directly influences agricultural productivity, food security and ecosystem health,” reads the report.
“Depending on a region’s climate, crop water needs may be met by natural precipitation, irrigation or a combination,” it continues. “Adequate water supply is essential for germination, growth and development of crops, affecting their yield, nutritional value and resilience to pests and disease. Furthermore, water plays a vital role in maintaining soil health and optimizing nutrient intake.”
Because agriculture is so reliant on water, EDF notes the industry is particularly susceptible to water-related risks from scarcity and excess.
Adverse impacts
To begin, EDF’s document outlines the adverse effects of water scarcity and excess.
EDF notes water scarcity, as a result of dry or drought conditions and/or human interventions, negatively impacts ag productivity by putting an early end to the growing season, permanently removing agricultural uses of land due to overuse or impacting water quality and nutritional value, which results in pasture loss and crop failure.
On the other hand, excess water is caused by heavy and/or prolonged precipitation or as a result of adverse soil and land management.
“Climate changes and land use, together with channelization, levee construction and urban floodplain development along large rivers, have driven worsening problem of excess water over the last century,” EDF states.
The organization further notes excess water can lead to waterlogging and flooding, both of which impact crop production.
According to EDF, adverse effects on agricultural production caused by these two stressors has been worsened by climate change in recent years.
“Climate change is creating more severe weather patterns, yielding more frequent and persistent droughts, as well as precipitation events of greater intensity,” the report reads.
“Further challenges arise from weather whiplash, in which there is a rapid transition from drought to floods or floods to drought,” it continues. “Weather whiplash is expected to become more frequent and extreme because of climate change.”
Additionally, EDF’s report notes the Federal Emergency Management Agency’s National Risk Index estimates the ag industry in the West and Midwest suffers combined annual losses of $2 billion from drought and riverine flooding.
Case studies
To dive into this issue even further, EDF conducted five case studies in different regions of the U.S – one in the Pacific Northwest, one in California, one in the Southwest, one in Kansas and one in the Midwest.
Across the four states of Nevada, Arizona, Utah and New Mexico, producers in the Southwest grow everything from livestock and hay to high-value grocery crops like lettuce and perennial crops like wine grapes.
“Due to the aridity of the region, irrigation is critical for crop production in all four Southwest states,” states the report. “The main water source in the Southwest is high-elevation snowpack runoff, which serves lower-elevation farms and communities.”
However, the report also notes this snowmelt runoff is predicted to decline in coming years due to climate change, which would stress agriculture in the region by reducing water available for irrigation.
According to EDF, this will increase heat stress, leading to increased crop failure; reduce livestock feed supply and decrease forage quality; shift hardiness zones and make it hard for existing crops to grow.
In the case study done on the Midwest – one of the most intensive crop production areas in the world, producing one-third of the world’s supply of corn – EDF found both water scarcity and excess will affect crop yields and yield variability.
“The projected high mean temperatures will affect crop production, especially for corn and especially in the south part of the region,” EDF states. “In addition, a warmer growing season translates to more days of high heat stress, which slows down crop growth and can result in crop reproductive failure and even death, again affecting yields.”
“Increased precipitation is likewise expected to lead to yield declines,” the report continues. “Waterlogged soils prevent plants form absorbing needed oxygen, leading to reduced growth or plant death.”
Mitigation strategies
In an effort to mitigate these issues, EDF’s report also mentions the organization is working with partners and stakeholders to advance science, develop new tools and implement policies and programs.
“Policies and programs which foster adaptation and resilience are needed at the nexus of agriculture and water to ensure there are sufficient water resources to meet human and ecosystem needs for future generations,” EDF states.
“This will include critically evaluating agroecological tradeoffs, such as which crop types and water management practices are most suitable in a given geography in light of population growth and climate change,” EDF continues.
Specifically, efforts highlighted in the report include encouraging land and crop management changes such as land repurposing, climate resilient crop production and soil health practices; improving infrastructure through on-farm water recycling and natural infrastructure for flood resilience; developing technology and decision-support tools such as OpenET and the Groundwater Accounting Platform and implementing policy and funding mechanisms through smart groundwater governance and financing solutions to support climate-smart agriculture investments.
Hannah Bugas is the managing editor of the Wyoming Livestock Roundup. Send comments on this article to roundup@wylr.net.
