The science of variable climate and agroecosystem management

Excerpt

Highly variable climate presents uncertainty and risk challenges to managing water and soil resources in agricultural landscapes. The Third National Climate Assessment documents increased climate disruptions to agriculture in the United States over the past 40 years and projects accelerated impacts in the next 25 years (Melillo et al. 2014). Loss and degradation of soil and water assets due to increasing extremes in precipitation (figure 1) are identified as key concerns to both rainfed and irrigated agriculture. The 2014 North America Regional Aspects Report by the Fifth Intergovernmental Panel on Climate Change cites rising temperatures and carbon dioxide (CO₂) concentrations, high vulnerability to climate extremes, increased wildfire activity, regional drought, pest infestations, land use changes, and pollution as stressing North American ecosystems (Romero-Lankao et al. 2014). The report further notes that water resources are already stressed by non-climate change anthropogenic factors, and effects of temperature and climate variability on yields of major crops have been observed.

Corn or maize (Zea mays L.), rice (Oryza sativa), soybean (Glycine max L.), and wheat (Triticum aestivum L.) provide 75% of the world's caloric intake. These are but four of the 17 principal cultivated crops planted on 131.4 million US ha (324.8 million US…