%0 Journal Article
%T Residual Effects of Biosolids Application on Forage Production of Semiarid Grassland in Jalisco, Mexico
%A Pedro Jurado-Guerra
%A Miguel Luna-Luna
%A Ernesto Flores-Ancira
%A Ruben Saucedo-Teran
%J Applied and Environmental Soil Science
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/835960
%X Single application of biosolids increases forage production on semiarid grasslands. Residual effects of biosolids on forage production have been scarcely measured in semiarid grasslands. The objective was to evaluate the residual effects of biosolids application on forage production of blue grama (Bouteloua gracilis (Willd. ex Kunth) Lag. ex Griffiths) and other grasses at a semiarid grassland in Jalisco, Mexico. The study was performed at shortgrass prairie in northeast Jalisco. Field plots were selected to include blue grama plants before rainy season in 2002. Aerobic biosolids were applied at 0 (control), 15, 30, 45, 60, 75, or 90 dry Mg£¿ha£¿1 under a completely random design with five replications. Forage production was estimated by clipping at the end of the growing season during five years. Data analysis was performed with linear mixed model and repeated measures. Forage production was influenced by a rate ¡Á year ¡Á species interaction ( ). Blue grama forage production increased with increasing biosolids rates during all years, with the magnitude of this response varying among years. Forage production of other grass species slightly decreased with biosolids application. Single biosolids application had a residual effect on forage production throughout five years in semiarid grasslands. 1. Introduction Approximately half of the world native grasslands show moderate to strong degradation [1], while approximately 95% of the grasslands are overgrazed and show degradation in Mexico [2]. Studies in Mexico indicate that most of the shortgrass prairie in Jalisco [3], Zacatecas, and Chihuahua [4] show moderate-extreme to extreme rangeland health. Oak-bunchgrass and Halophyte grasslands also show deterioration, including high invasion of native shrubs and exotic grasses in Chihuahua [5]. Practices to recover degraded grasslands may include use of fertilizers, prescribed fire, shrub management, and soil and water conservation techniques. Fertilizer application to native grasslands has increased forage production [6, 7] although high fertilizer costs make this a low profitability technique. An alternative might be application of organic byproducts such as biosolids that are generated at wastewater treatment plants and can be used as fertilizer and soil amendments [8, 9]. Several studies have shown that surface-applied biosolids promote grass production at arid and semiarid grasslands [10¨C12]. Biosolids rates from 18 to 45£¿Mg£¿ha£¿1 have been recommended for arid rangelands with good agronomic results in terms of grass forage production and soil fertility [13].
%U http://www.hindawi.com/journals/aess/2013/835960/