Land Application of Treated Industrial Wastewater on a Chihuahuan Desert Shrubland: Implications for Water Quality and Mineral Deposition

• Published in: Arid land research and management Vol. 26; no. 3; pp. 211 - 226
• Main Authors: Picchioni, Geno A, Shukla, Manoj K, Mexal, John G, Babcock, Michael, Ruiz, Alejandro, Sammis, Theodore W, Rodriguez, Denise S
• Format: Journal Article
• Language: English
• Published: Philadelphia Taylor & Francis Group 01.07.2012; Taylor & Francis Ltd
• Subjects: adsorption; alkalinity; calcium carbonate; chlorides; effluent; electrical conductivity; evapotranspiration; freshwater; indigenous species; irrigation; land application; landscapes; Larrea tridentata; Leaching; long term effects; nutrients; potassium; Prosopis glandulosa; Recycling; salinity; semiarid zones; shrublands; shrubs; sodicity; sodium; soil analysis; soil depth; Soil fertility; soil quality; Tridentata; Vegetation; wastewater; wastewater irrigation; Water quality; Water treatment; Mexico, Chihuahuan Desert
• ISSN: 1532-4990; 1532-4982; 1532-4990
• DOI: 10.1080/15324982.2012.680656

Land application of wastewater conserves fresh water and recycles nutrients, but little is known of its impacts on arid and semiarid landscapes. Lagoon treated saline−sodic industrial effluent was applied from 2002–2005 to a 0.4-ha Chihuahuan Desert shrubland to assess the deposition and recovery of effluent components and changes in soil quality vis-à-vis a non-irrigated area. Effluent irrigation supplied 26% of the average annual nonstressed evapotranspiration (ET) of the native shrubs [Larrea tridentata (DC.) Coville and Prosopis glandulosa Torr. var. glandulosa], and increased both soil stress factors (sodicity, salinity, and pH) and soil fertility (N, P, and K). After 3 yr, the soil saturation extract electrical conductivity (ECₑ) reached as high as 6.1 dS m⁻¹ and Cl⁻ 76 molc m⁻³ at 105 cm depth under irrigated L. tridentata. After 4 yr, saturation extract sodium adsorption ratio (SARₑ) reached 25–35 at 7.5 cm under the irrigated shrubs and intershrub spaces. There were 27 Mg ha⁻¹ of cumulative ionic deposits to the site comprised mostly of Na⁺, Cl⁻, and CaCO₃ equivalent alkalinity, with soil analysis recovering most of the deposits (>57%) except for K⁺ and Na⁺ (8% to 13%). Subsurface leaching of and P was detected within the upper 1 m soil depth after 4 yr, and a high downward mobility of Cl⁻ revealed the potential for deeper leaching at higher N loading rates. While long-term effects on the natural vegetation are unknown, results contribute to a limited scientific database for sustainable wastewater land application in semiarid regions.