Author
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Sojka, Robert |
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Submitted to: Book Chapter
Publication Type: Book / Chapter Publication Acceptance Date: 1/1/1997 Publication Date: N/A Citation: N/A Interpretive Summary: Irrigated agriculture produces 1/3 the global harvest and 1/2 the value of harvested goods on 1/6 of earth's crop land. Irrigation's advantage comes in part from it's predominant association with aridity and arid soils. High sunshine, low humidity, high base saturation, and low soil organic matter maximize photosynthesis while reducing fertilizer and lime requirements, insect and disease pressure, and appplication requirements of soil-incorporated herbicides and pesticides. Arid soils are generally more fragile and suscptible to erosion impairment than wetter soils. Dozens of ways have been developed to minimize irrigation-induced erosion. Successful methods usually couple high conservation efficacy with ease implementation. Irrigation induced erosion has not been successfully modeled, because the unique systematics of irrigation induced erosion are not considered in existing soil erosion models, which are all based on rain-derived systematics. Water quality impacts, reduced water flow with increasing slope length, and effects of erosive streams instantaneously hydrating dry soil are among the key deficiencies of rain-based soil-erosion models. Technical Abstract: Irrigated agriculture produces 1/3 the global harvest and 1/2 the value of harvested goods on 1/6 of earth's crop land. Irrigation's advantage comes in part from it's predominant association with aridity and arid soils. High sunshine, low humidity, high base saturation, and low soil organic matter maximize photosynthesis while reducing fertilizer and lime requirements, insect and disease pressure, and appplication requirements of soil-incorporated herbicides and pesticides. Arid soils are generally more fragile and suscptible to erosion impairment than wetter soils. Dozens of ways have been developed to minimize irrigation-induced erosion. Successful methods usually couple high conservation efficacy with ease implementation. Irrigation induced erosion has not been successfully modeled, because the unique systematics of irrigation-induced erosion are not considered in existing soil erosion models, which are all based on rain-derived systematics. Water quality impacts, reduced water flow with increasing slope length, and effects of erosive streams instantaneously hydrating dry soil are among the key deficiencies of rain-based soil-erosion models. |
