Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/1/2004
Publication Date: 3/1/2005
Citation: Allen, V.C., Brown, C.P., Green, C., Krieg, D., Segarra, E., Kellison, R., Wheeler, T., Dotray, P., Acosta Martinez, V. 2005. Integrating cotton and beef production to reduce water withdrawn from the ogallala aquifer. Agronomy Journal. 97(2):556-567. Interpretive Summary: Interpretative summary: There are two major problems in the cotton production of the Texas Southern High Plains region, USA. First, cotton produced continuously under tillage practices reduces soil organic matter, and this makes the soil more easily eroded by wind. Another problem is that cotton has used irrigation with water from the Ogallala aquifer, but this aquifer is having less water available over the years. Even though a lot of cattle exist in Texas, cotton production has not been integrated with livestock production, which may require less water and may benefit soils. This study compared the water use, productivity and economics of two systems: (1) a continuous monoculture system and (2) an integrated cotton crop-livestock system during five years from 1998 to 2002. The integrated cotton crop-livestock system included cotton in a 2-paddock rotation with grazed wheat and rye and a perennial old world bluestem pasture for grazing and seed production. Over the 4 years of this study, cotton lint yield of the continuous monoculture system was similar to the integrated cotton crop-livestock system. However, the integrated cotton crop-livestock system reduced water use by 23% and N fertilizer by 40% as well as it required fewer other chemical inputs compared to the continuous cotton system. These results indicate that the integrated cotton crop-livestock systems are less dependent on irrigation and chemical inputs while improving profitability.
Technical Abstract: Agriculture in the Texas High Plains depends heavily on irrigation with water withdrawn from the Ogallala Aquifer at non-sustainable rates. Our hypothesis was that an integrated crop and livestock system would reduce irrigation water use, maintain profitability, and diversify income compared with a cotton (Gossypium hirsutum) monoculture. Thus, form 1998 to 2002, two large scale systems, with 3 replications in a randomized block design, compared water use, productivity, and economics of 1) a cotton (var 'Paymaster 2326RR') monoculture with terminated wheat (Triticum aestivum); and 2) an integrated 3-paddock system that included cotton in a 2-paddock rotation with grazed wheat and rye (Secale cereale) and the perennial 'WW-B. Dahl' old world bluestem (Bothriochloa bladhii) for grazing and seed production. All paddocks were irrigated by sub-surface drip. Depth to water in supply wells was about 90m. Angus cross bred stocker beef steers (initial BW 249 kg: SD=26 kg) grazed from January to mid-July. Over the 4 years of this experiment following the establishment year, cotton lint yield was 1,036 and 1,062 kg ha-1 for the cotton monoculture and the integrated system, respectively. Bluestem seed yield averaged 24 kg pure live seed ha-1. Steers gained 153 kg on pasture and 0.82 kg d-1. Per hectare, the integrated system reduced (P<0.001) irrigation water by 23%, N fertilizer by 40%, and required fewer other chemical inputs in the cotton monoculture. Profitability was about 50% greater for the integrated system at the 90-m pumping depth. Integrated production systems that are less dependent on irrigation and chemical inputs appear possible while improving profitability.