Cherubin Maurício Roberto, Canisares Lucas Pecci, Souza Lucas Nogueira, Pinheiro Junior Carlos Roberto, Moraes Moacir Tuzzin de, Bertol Felipe, Bortolo Larissa, Menillo Rafael Braghieri, Cerri Carlos Eduardo Pellegrino
Luiz de Queiroz College of Agriculture - University of São Paulo, Piracicaba, SP, Brazil; Center for Carbon Research in Tropical Agriculture, University of São Paulo, Piracicaba, SP, Brazil.
Luiz de Queiroz College of Agriculture - University of São Paulo, Piracicaba, SP, Brazil; Center for Carbon Research in Tropical Agriculture, University of São Paulo, Piracicaba, SP, Brazil.
J Environ Manage. 2025 Sep;392:126845. doi: 10.1016/j.jenvman.2025.126845. Epub 2025 Aug 7.
Crop diversification strategies can improve soil health while maintaining high yields. Healthy soils perform multiple functions that can also increase resilience to climate change. However, these benefits have yet to be demonstrated in the Brazilian savannah (Cerrado biome), one of the world's largest agricultural production regions and also one of the most vulnerable to climate change. Thus, this study evaluates the long-term (16 years) effects of crop diversification systems, including crop successions and rotations, and soybean monocropping (control), on soil health, grain yield, and yield stability in the Brazilian savannah. The experiment involved seven cropping systems with soybean as the main cash crop, integrating pearl millet, ruzigrass, sunn hemp, and/or maize into the different successions and rotations. Soil health data includes 23 indicators (8 chemicals, 10 physicals and 5 biologicals). Crop yield and weather data from the last 6 years (two rotation cycles) were analyzed. Soybean yields were higher under crop diversification compared to monocropping (soybean-fallow) (3948 - 4321 kg ha vs. 2282 kg ha), with reduced yield variability (5-9 % vs 19 %). Results showed that crop successions and rotations enhanced soil health indicators (mainly biological and physical) compared to soybean-fallow monocropping, resulting in higher soil health index and soil's multifunctionality. We observed a higher amplitude of grain yield in drier and warmer years and observed a positive linear relationship between soil health index and water use efficiency. Treatments with higher soil health index result in higher water use efficiency (3.1-3.5 vs. 1.8 kg ha mm of soybean grain) than monocropping, with successions and rotations enhancing systems' resilience compared to monocropping. In conclusion, long-term crop diversification, particularly including cover crops with high biomass accumulation, was an effective strategy to enhance soil health, productivity, and resilience in tropical agroecosystems in the Brazilian savannah. In addition, we suggest that the soil health index be used as a comprehensive indicator for assessing the effectiveness of climate change adaptation strategies in agroecosystems.
作物多样化策略可以在保持高产的同时改善土壤健康状况。健康的土壤具有多种功能，还能增强对气候变化的适应能力。然而，在巴西大草原（塞拉多生物群落）这一世界最大的农业生产地区之一且也是最易受气候变化影响的地区之一，这些益处尚未得到证实。因此，本研究评估了作物多样化系统（包括作物连作和轮作）以及大豆单作（对照）对巴西大草原土壤健康、谷物产量和产量稳定性的长期（16年）影响。该实验涉及七个种植系统，以大豆作为主要经济作物，将珍珠粟、黑麦草、印度麻和/或玉米纳入不同的连作和轮作中。土壤健康数据包括23项指标（8项化学指标、10项物理指标和5项生物指标）。分析了过去6年（两个轮作周期）的作物产量和天气数据。与单作（大豆-休耕）相比，作物多样化条件下的大豆产量更高（3948 - 4321千克/公顷对2282千克/公顷），产量变异性降低（5 - 9%对19%）。结果表明，与大豆-休耕单作相比，作物连作和轮作增强了土壤健康指标（主要是生物和物理指标），从而提高了土壤健康指数和土壤多功能性。我们观察到在较干旱和较温暖年份谷物产量的波动幅度更大，并且观察到土壤健康指数与水分利用效率之间存在正线性关系。土壤健康指数较高的处理比单作具有更高的水分利用效率（3.1 - 3.5对1.8千克/公顷·毫米大豆籽粒），连作和轮作相比单作增强了系统的适应能力。总之，长期的作物多样化，特别是包括具有高生物量积累的覆盖作物，是增强巴西大草原热带农业生态系统土壤健康、生产力和适应能力的有效策略。此外，我们建议将土壤健康指数用作评估农业生态系统气候变化适应策略有效性的综合指标。
