El impacto de la ganadería y la agricultura en los ecosistemas terrestres.-Fertilizacion orgánica y prácticas de conservación sobre el rendimiento de sorgo de temporal

Abstract

ABSTRACT The interelations between climatic and soil conditions present in the agroecosystems of the dry zone of northern Mexico, have significant impact on the development of crops that result in impact on agricultural productivity. Soil degradation by excessive use of mechanical practices, has caused severe physical and chemical changes such as deterioration of the natural structure, loss of fertility, increased soil compaction and bulk density, and serious problems of erosion by wind and water. In order to know the influence of three organic fertilizers and soil preparation practices in the production of sorghum in San Fernando, Tamaulipas, was conducted this study. The experimental area presents Vertisol soil type, and covers an area of 6 ha, which was subdivided into plots of one hectare. Each hectare was assessed with two conditions of fertilization with organic fertilizer (chicken manure at a rate of 2 Tm ha-1) and three tillage systems. The types of tillage were: a) continuous tracking surface (control), b) along with dams or between rows, and c) subsoleo. The crop used was sorghum for grain (Asgrow hybrid Emerald), with a population density of 172,800 plants per hectare. We used a completely randomized design with four replications and factorial analysis. The results show significant differences (p = 0.05) between the superficial tillage (harrow) and maintenance (subsoleo or dikes). With superficial tillage lower yields were obtained (2,15 Tm ha-1), whereas with dikes or subsoleo yield increased by 50% in a similar manner. The effect of organic fertilization with chicken manure increased the yield by 10% compared with the control. With deep tillage (subsoleo and dikes) combined with chicken manure is an option to obtain the best yields in rainfed area of northern Tamaulipas.