Effects of Long-Term Crop-Livestock-Forestry Systems on Soil Erosion and Water Infiltration in a Brazilian Cerrado Site

摘要

Integrating agricultural land uses is a suitable alternative for fostering economic development and improving food security. However, the effects of long-term integrated systems on soil erosion and water infiltration are still poorly understood. Here, we investigate the influence of different agricultural land uses on soil erosion and water infiltration in an Oxisol site located in the Brazilian Cerrado region. The experimental area consisted of continuous grazing under variable stocking rates with regular fertilization (CG-RF), continuous cropping under no-till (CC-NT) and no-till with 4-year subsoiling (CC-SS), rotation of one year cropping and three years livestock in the livestock phase (C1-L3), rotation of four years cropping and four years livestock in the cropping phase (CL-4C) and in the livestock phase (CL-4L), and integrated crop-livestock-forestry in the cropping phase (CLF-C) and in the livestock phase (CLF-L). To evaluate water infiltration and soil loss, we used a rainfall simulator with a constant rainfall intensity of 74.9 ± 3.6 mm h−1 in plots of 0.7 m2. We carried out 72 rainfall simulations comprising four repetitions in each treatment under vegetation and bare soil. Stable infiltration rate (SIR) ranged from 45.9 to 74.8 mm h−1 and 19.4 to 70.8 mm h−1 under vegetation covers and bare soil, respectively. Our findings indicated that SIR values under CLF-C were 60% greater than under CG-RF. We also found that soil loss rates under CLF-C were 50% smaller than under CG-RF. The crop−livestock rotation period that presented better results of SIR and soil loss was one year of cropping and three years of livestock (C1-L3). Overall, we noted that SIR and soil loss values under CLF-C are similar to the Cerrado native vegetation. Therefore, our study reveals the opportunity to increase agricultural production, improve food supply, and reduce soil erosion with adequate soil and agricultural management.