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Integrated crop-livestock systems (ICLS) can be an alternative to increase the productivity of agroecosystems by enhancing nutrient cycling via grazing animals. Despite the holistic approach that bears the designing of ICLS, fertilization practices are proceeded in a conventional crop basis, disregarding nutrient fluxes at the appropriate spatial and temporal dynamics. We argue that fertilization practices in ICLS must follow the same integrated approach. To test this, we compared a conventional crop fertilization strategy versus a system fertilization approach applied to two production systems being a conventional cropping system and ICLS. The conventional cropping system consisted of a soybean crop succeeded by a non-grazed Italian ryegrass cover crop. The ICLS model consisted of a soybean-Italian ryegrass rotation grazed by sheep. In the conventional crop fertilization strategy phosphorus and potassium were applied at soybean sowing and nitrogen at the Italian ryegrass establishment. The system fertilization consisted of the application of all nutrients during the Italian ryegrass establishment. Accordingly, treatments were fertilization strategies in a factorial framework with production systems randomly distributed in a complete block design with four replicates. Results indicated for the first time greater daily herbage accumulation rate (24%; P < 0.01) and total herbage production (18%; P < 0.05) in the system fertilization compared with conventional crop fertilization. Consequently, system fertilization allowed for greater stocking rates in the pasture phase (17%; P < 0.05). The ICLS presented greater equivalent soybean yield (P < 0.001), energy production (P < 0.01), and system productivity (P < 0.05) compared with the cropping system, regardless of fertilization strategies. Soybean yield was not affected by fertilization strategies or grazing. In conclusion, the adoption of system fertilization strategy and crop-livestock integration enhance the production without jeopardizing soybean grain yields, so that land use is optimized by a greater energy production per unit of nutrient applied. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the growth performance, forage intake and methane (CH 4) emissions by beef cattle grazing under different spatiotemporal integrated crop-livestock systems (ICLSs). The experiment was conducted for two years (2017–2018 and 2018–2019) in warm season perennial pastures and cool season annual pastures grazed by beef steers. Three pesticide-free ICLS treatments – livestock-forestry (LF); crop-livestock (CL), and crop-livestock-forestry (CLF) – plus, a livestock control pesticide-free system (L) were conducted in randomized complete block design, with three replicates per treatment. Maize crop rotation was done with cool season cover crop under no-tillage. Eucalyptus trees (Eucalyptus benthamii) were planted in 2013 and intercropped with tree alleys. The animal performance, organic matter (OM) intake and enteric CH 4 emission, yield, and intensity were assessed. We found no significant difference (P > 0.05) for average daily gain (ADG), stocking rate (SR), and daily live weight gain (LWG) per area for the different ICLS arrangements and seasons. The ICLS arrangements did not affect (P > 0.05) CH 4 emission, yield, and intensity, with averages of 186 g steer−1 day−1, 26 g kg−1 OM intake and 210 g kg−1 of ADG, respectively. The average CH 4 emissions per steer per day, per OM intake, per ADG and LWG per area were greater (P < 0.05) for steers when grazing warm season compared to cool season pastures. The integration or not of beef cattle with crops and/or forestry does not influence CH 4 emissions, yield, and intensity by beef steers grazing pastures under moderate grazing intensity. Our results reinforce that well-managed integrated systems are a reliable climate-smart agriculture alternative for increasing production, e.g., grain, wood, meat, and mitigating or without increasing greenhouse gas emissions, such as CH 4 from enteric fermentation in beef cattle. • Different ICLSs do not affect the beef cattle's performance in moderate grazing management. • Intake and forage quality of pastures are not affected by ICLS arrangements. • ICLS arrangements do not affect enteric CH 4 emission. • CH 4 emissions were higher in warm season than cool season pastures. • A well-managed ICLS is an important diver of sustainability. [ABSTRACT FROM AUTHOR]