The topic is populating headlines: "Agency Likely to Cut Water to Rice Farms" and "Push Comes to Shove Over Water Restrictions." These are just two recent examples how the fight for water is leading to moratoriums on irrigation, complaints over property rights, diminished crop yields, even job loss. And it's worse in developing countries where drought ranks as the most common cause of food shortages, according to the United Nations on this date designated as World Water Day.
Raising Awareness on World Water Day 2012
The annual international designation continues to grow in focus and importance every year. It began as an opportunity to celebrate and raise awareness about the importance of a freshwater supply by the United Nations Conference on Environment and Development in 1992. The United Nations General Assembly supported the effort by designating March 22, 1993 as the first official World Water Day.
Learn more about this year's focus on water and food security, here: http://www.unwater.org/worldwaterday/faqs.html
Trouble in Texas Leads to Emergency Plans and Policy
The Lonestar State's water woes is pushing many agribusinesses to prepare for the worst. Ronald Gertson's family grows rice in the claylike soil near Lissie, in Southeast Texas. He believes it's the first time in five generations, there's worry about the water supply. Gertson says, "I can grow about a third of my rice using groundwater. If I push it, I might get 45-percent of the acres I normally plant. But many of my neighbors and I are already looking at what we can do to cut costs in what is clearly going to be a hard year." Texas usually produces 5-percent of the nation's rice but the region is implementing emergency plans now, which may mean water will not be released from lakes and rivers for irrigation this summer, following one of the most severe droughts in state history last year.
It's no different in West Texas. But this is where the concern could lead to complaints filed in protection of rights to water for crops. A Texas Supreme Court opinion is confirming, those who own the land, also own the water beneath their property. It's similar to rulings for landowners when it comes to oil and gas. J.O. Dawdy has grown cotton in fields outside Floydada, for more than 36 years. New regulations may limit the amount of water he and other agribusiness owners can withdraw from the aquifer and requires new wells have meters installed to measure use. And while Dawdy may go to court over water, others like Don Marble, support the policy. "If we don't do something to try and get some kind of control on how much water we're pumping, we may be looking for drinking water, it's that serious," says the 80-year-old cottom producer.
However, there's at least one law professor, monitoring the situation and noting Texas is the only state functioning via the rule of capture, which allows landowners to pump almost unlimited amounts of water for their crops. University of Arizona's Robert Glennon indicates a number of states, including Colorado, Arizona and Idaho-- have restricted the amount of water pumped. Back in Texas, penalties for pumping excess water on crops are being delayed until 2014, with officials hoping some will self-enforce.
A "Grand Challenge" for the Crop Science Society of America
Water is such a key input for crop growth, there are no real alternatives, according to Crop Science Society of America President Jeffrey Volenec. The Purdue University Professor of Agronomy describes water as serving several functions in plants, saying, "As stomata, the microscopic pores in leaf surfaces open to allow carbon dioxide to enter leaves for the all-important process of photosynthesis. Water exits these pores at a very high rate in a process called transpiration. In fact for most crop plants, the mass of water lost through leaves, relative to the mass of crop plant growth produced largely through photosynthesis, occurs at a ratio of 500/1 to 1500/1 (crop species dependent). This means between 500 and 1500 pounds of water can be used by plants (mainly transpiration and a small amount of soil evaporation) for every 1 pound of plant dry matter produced. Extended to a field scale where many tons of plant dry matter are produced every year, both as grain and straw, you immediately realize thousands of tons of fresh water are needed for crop production for each acre in production. This is one of the principle reasons rain-fed regions (e.g., the East and Central US, the corn belt) are intensively farmed. This tremendous water use by crop agriculture is also at the center of the debate for water rights; urban versus agricultural use, and the sustainability of agriculture and our communities in dry regions."
Volenec goes to to say, "Some have suggested we can save water by simply reducing transpiration of crop plants (chemically or genetically) and there may be room for slight improvement in water use efficiency. However, the second key function transpiration serves-- is cooling plants and temperature control. When transpiration slows because of partial or complete stomata closure, evaporative cooling ceases and plant temperatures will increase abruptly.
"In addition, photosynthesis slows or stops, and since 90 to 95% of plant dry weight is derived from this process (5 to 10% from soil minerals), closing stomata is likely to also reduce yield. As we look to the future, climate change is predicted to alter spatial patterns, intensities and seasonal distributions of rainfall. It also will alter temperatures and humidity; all of which can impact crop growth and yield. It is why understanding the factors driving climate change, and finding ways to mitigate these changes while simultaneously improving crop adaptation to climate change, represents one of the “Grand Challenges” targeted as a mission of CSSA and agribusiness, in general," explains Volenec.
And as they're finding in Texas, the challenge is-- how quickly can change occur, in a mutually respectful and responsible manner. Luckily, it's an important goal of CSSA and its cooperating societies to find answers at all steps of the supply chain, from producers to consumers, knowing actions taken now, can save water and ensure food for all, in the future.
(Photo of Crop Science Society of America President and Purdue Professor Agronomy Jeffrey Volenec, courtesy: Purdue University)