Instituto de Zootecnia/APTA/SAA, Ribeirão Preto, SP, 14030-670, Brazil.
Instituto de Zootecnia/APTA/SAA, Nova Odessa, SP, 13460-000, Brazil.
Sci Rep. 2022 Jul 14;12(1):12021. doi: 10.1038/s41598-022-15615-7.
The rational use of nutrients is a key factor for the sustainability of agricultural systems. This study aimed to analyze the nitrogen balance and use efficiency, and the valorization of organic residues within integrated systems, in comparison to conventional agricultural and livestock systems. The experiment was assembled in a randomized blocks design with three replicates. Six production systems were compared, grain maize production (CROP) and pasture for beef cattle production (LS), and four ICLS (Integrated Crop-Livestock System) for grain maize and pastures for beef cattle, in 2 years. In order to estimate the nutrients balance, inputs, and outputs at farm levels were considered, and with the results obtained for nutrient balance, the use efficiency was calculated. The CROP presented higher nutrient use efficiency (1.43 kg/ha), but at the same time, it resulted in negative contributions for the nutrient balance (-97 kg/ha) because of lower amounts of nitrogen in the organic residues (188 kg/ha) and lower valuation. The LS and ICLS provided a higher amount of nitrogen (983 kg/ha; mean ± 921 kg/ha) and valuation of organic residues. The presence of components such as pastures and the animal contribute to a positive production system, while reducing the needs for chemical fertilizers.
养分的合理利用是农业系统可持续性的关键因素。本研究旨在分析氮素平衡和利用效率，以及综合系统中有机残留物的增值，与传统农业和畜牧业系统进行比较。该实验采用随机区组设计，设 3 个重复。比较了 6 种生产系统，包括粮食玉米生产（CROP）和肉牛生产的牧场（LS），以及 4 种粮食玉米和肉牛牧场的 ICLS（综合作物-牲畜系统），共 2 年。为了估计养分平衡，考虑了农场层面的投入和产出，根据养分平衡的结果计算了利用效率。CROP 表现出更高的养分利用效率（1.43kg/ha），但同时由于有机残留物中氮含量较低（188kg/ha）和较低的估值，导致养分平衡呈负值（-97kg/ha）。LS 和 ICLS 提供了更高数量的氮（983kg/ha；平均值±921kg/ha）和有机残留物的估值。牧场和动物等组成部分的存在有助于形成正向的生产系统，同时减少对化肥的需求。
