Engineering technologies for site-specific irrigation management (SSIM) have already been developed for applications in precision irrigation. However, further studies are needed to identify scenarios where SSIM leads to better agronomic outcomes than conventional uniform irrigation management (CUIM). The objective was to conduct a long-term simulation study to compare SSIM and CUIM given spatial soil variability at the Maricopa Agricultural Center (MAC) in Arizona. More than 500 surface soil samples were collected across a 730-ha area of the MAC from 1984 to 1987. A more detailed soil data set was more recently obtained across a 5.9-ha area at a MAC location designated for SSIM studies. Ordinary kriging was used for spatial interpolation of soil hydraulic properties within $$10\,\hbox {m} \times 10\,\hbox {m}$$ 10 m × 10 m zones across the MAC, and 11 field parcels with an area of approximately 60 ha were delineated on the MAC quarter sections. Using an agroecosystem model, simulations of cotton production at the zone level with a 30-year weather record were conducted using a field-tested algorithm to optimize irrigation schedules for SSIM and CUIM. Long-term seed cotton yield, irrigation requirements, water use efficiency, and marginal net return for SSIM and CUIM strategies were often not different ( $$p>0.05$$ p > 0.05 ). Differences in seed cotton yield and irrigation requirements among the tested irrigation strategies were less than 11% and 6%, respectively, and within the typical range of model error. Most soils on the MAC have enough available water holding capacity to sustain cotton production at full potential with weekly CUIM, and advantages of SSIM were not consistently demonstrated by the simulations.

中文翻译：

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亚利桑那州棉花生产现场特定灌溉管理的长期模拟

特定地点灌溉管理 (SSIM) 的工程技术已经开发用于精确灌溉。然而，需要进一步的研究来确定 SSIM 比传统的统一灌溉管理 (CUIM) 带来更好的农艺结果的场景。目标是在亚利桑那州马里科帕农业中心 (MAC) 进行长期模拟研究，以比较 SSIM 和 CUIM 给定的空间土壤变异性。从 1984 年到 1987 年，在 MAC 的 730 公顷区域收集了 500 多个表层土壤样本。最近在指定用于 SSIM 研究的 MAC 位置的 5.9 公顷区域中获得了更详细的土壤数据集。普通克里金法用于 $10\,\hbox {m} \times 10\,\hbox {m}$$ 10 m × 10 m 跨 MAC 区域内土壤水力特性的空间插值，和 11 个面积约 60 公顷的田地地块被划定在 MAC 四分之一部分。使用农业生态系统模型，使用田间测试算法对具有 30 年天气记录的区域级别的棉花生产进行模拟，以优化 SSIM 和 CUIM 的灌溉计划。SSIM 和 CUIM 策略的长期籽棉产量、灌溉要求、用水效率和边际净回报通常没有差异（$$p>0.05$$p>0.05）。测试的灌溉策略之间的籽棉产量和灌溉需求差异分别小于 11% 和 6%，并且在模型误差的典型范围内。MAC 上的大多数土壤具有足够的可用持水能力，可以通过每周 CUIM 来维持棉花生产的全部潜力，