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Conference offers climate change challengeA centuries-long view of climate patterns and how it affects western Great Plains agricultural sustainability was among one topic of discussion during the "Sustainability Management 2009" conference, held in Denver. More than 500 farmers, academics, consultants and other ag industry experts participated in the three-day conference. In light of increasing pressure on western Corn Belt water supplies, the conference was designed to help producers establish best management practices for water utilization, as well as land and energy resources. Sponsored by Monsanto, the event examined such key issues as water, climate and global food trends, irrigation and fertility management, new seed and trait technologies, and other technological developments in agriculture aimed at helping farmers produce and conserve more water. Dr. Chuck Rice, University Distinguished Professor of soil microbiology in the department of agronomy at Kansas State University, delivered one of the conference's major addresses on the state of the global climate, the role of carbon served and how they both affect area agriculture. Rice is one of more than 100 members of the Intergovernmental Panel on Climate Change (IPCC) from around the world who, along with former Vice President Al Gore, won the 2007 Nobel Peace Prize for their efforts to spread awareness of man-made climate change and lay the foundations for counteracting it. Rice was one of the lead authors of a chapter on the IPCC's fourth assessment report on mitigation of climate change. The chapter focused on agriculture, including carbon sequestration and land use. Rice was the only scientist from the U.S. to author work in that section. Rice was a part of an IPCC working group addressing the issue of how to reduce greenhouse gas levels in the atmosphere. One of the techniques on how greenhouse gases can be reduced, the working group reported, is no-till production. Through no-till, organic carbon levels in soils can be increased. Increasing soil carbon levels through soil carbon sequestration helps reduce carbon dioxide levels in the atmosphere. Soil carbon sequestration is one of the most cost-effective ways of reducing greenhouse gases. In his presentation, Rice showed how research over the past several years has proven that agriculture can become a key player in helping to mitigate global warming and climate change, since untilled soil stores carbon dioxide rather than releasing it into the air. Rice brought that research to bear in his conference presentation, offering data indicating how the earth has warmed over the last 150 years, with human factors responsible for causing a shift in normal warming and cooling cycles of the planet. "We've seen all the models, including natural forces like solar cycles and volcanoes and other things that have occurred to affect the climate," Rice said. "However, over the last 40 years, there has been a diversion from these natural forces. If you add in anthropogenic factors, primarily aerosols, greenhouse gases, CO2, nitrous oxide and methane, do the models match up with what's observed." Carbon buildup Using carbon dating, Rice then outlined how carbon has built up and diminished in cycles over the last 150,000 years. About 150 years ago CO2 was measured at 280 parts per million, about the top of the last several cycles, only this time, CO2 concentrations continued to climb without end. "Today, we're at about 388 parts per million. When I first started at K-State in 1988, CO2 concentrations were at about 350 parts per million," Rice said. "Of the major greenhouse gases--CO2, methane and nitrous oxide--CO2 has seen the most increase. Since the mid 1880s, over 80 percent of the increase in CO2 emissions have been due to the burning of fossil fuels." Globally, agriculture is responsible for only 13 percent of greenhouse gas emissions and just 6 percent of U.S. emissions. "It varies from country to country and, here, even state to state," Rice said. "A state like Kansas has more agricultural emissions, being a farm state, compared with others more dependent on transportation." These emissions, Rice said, are responsible for an overall 1 degree Celsius increase in the global temperature. "It's not consistent, you have to look at long term trends," Rice said. "We had some cooling in the 1920s due to solar cycles and volcanoes. Right now, we are flattening out, but you have to look long-term." The only problem with looking at a global average temperature increase, Rice said, is that there will be larger changes at some locations and smaller changes elsewhere. Winters are predicted to be wetter in middle latitudes with summers expected to be drier. "It's looking like as much as a 7 degree Centigrade increase in temperature in the Polar regions," the K-State soil scientist said. "There are high degrees of confidence in these models. In the middle part of the U.S., you are looking at about a 2 to 3 degree increase." Showing research from the IPCC report, Rice said that as temperatures increase, water availability would decrease. "This means there will be greater competition for water resources between human populations and agriculture," Rice said. "With these climate changes, there will be great challenges for producing food. Over the next 20 years, in North America and Russia, there likely will be greater crop productivity, but as it gets warmer, productivity will likely decrease." Changes in temperature and moisture will affect transpiration, making for more dry days, Rice said. "Even in places like Brazil, that we think of as a wet climate, will be affected by more dry days," he said. Working with Dr. Johan Federman, a climatologist at the University of Kansas, Rice has been examining projections for High Plains climate. "We're looking at a general moisture deficit, while taking stock of the moisture received last winter," Rice said. "This is a pretty middle-of-the-road projection, neither high or low. We are looking at an increase in temperature over the next century of 3 degrees Celsius or 6 degrees Fahrenheit. For precipitation, about a 3 percent annual increase with dry summers. That's the equivalent of a 8 inch moisture deficit." Changes ahead? Because of higher temperatures, it will mean that more precipitation will be needed to grow the same amount of crops. "This is a startling increase in crop pressure and moisture deficits in Great Plains agriculture," Rice said. "In fact, these pressures and deficits already are happening." "What we might see are more extreme weather events," Rice added. "Storms may be less frequent but more intense. This has big implications on the environment, with more flooding, more runoff, and less effective use of moisture with more dry cycles between those events." Rice said the IPCC report indicates higher numbers of heat waves and briefer precipitation periods. For a short time, there may be increased crop yields, but this will be mitigated by constraints of water resources. "Even if temperatures overall don't change, you'll see warmer nights and winters. Some growth cycles will see an increase of weeds and other pests and diseases, since they are affected by freezing temperatures," Rice said. "More inputs will be required from pesticides and herbicides; more nitrogen will be needed to capture increased yields, which will increase costs," Rice said. "Greater increases in variability will be seen." Rice sees agriculture as having a tremendous opportunity to mitigate increases in CO2 emissions. "Ag has greater potential than forestry, than new energy sources, or transportation, to mitigate these increases," Rice said. "They are available now." As much as 15 percent of that mitigation can come through agriculture. Of that, Rice said, 85 percent can come through carbon sequestration. "It has strong synergies with sustainability to help reduce our vulnerability to climate change," Rice said. "Carbon sinks, reducing emissions and providing biomass for biomass or recycling carbon." Climate change will also affect how microbes act in soils as well as plant growth, Rice said. Changing how residues are managed can also do those same things. "Using no-till, reduced-till, and strip-till can all alter the carbon cycle. Rotations also are important in that. Cover crops are good for water management. On grasslands, even burning tallgrass prairie can be good for increasing carbon levels in the soil," Rice said, who went on to expound on the well-known benefits of no-till, including reduced fuel usage, which reduces carbon output, as well as economic and wildlife benefits. "Carbon increases microbial activity, which is good for the soil," Rice added. With that in mind, Rice called on the Obama Administration to implement a strong cap-and-trade system to capture the mitigation potential of no-till agriculture versus other sources. "It will require a database showing different practices on how soil carbon sequestration levels," Rice said. "By using this data, we can develop a strong carbon market, using aggregators to help farmers sell carbon credits to those major carbon users." Rice sees a $2.75 per acre payment to no-till producers under current voluntary systems with as much as a $14 per acre payment under a mandatory system. "If you compare it to typical prices, that's equal to wheat on the U.S. basis," Rice said. "Whether you agree with it or not, there will climate change legislation and agriculture must be a part of it. You may think this is a bunch of baloney, but in 2005 Scientific American looked at the future farm and saw that over half of all future income will come from credits to protect the land, water and air." Larry Dreiling can be reached by phone at 785-628-1117, or by e-mail at ldreiling@aol.com.
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