Mulching is a widely adopted agronomic practice, often used as a water-saving strategy due to its effectiveness in reducing soil evaporation. However, effects vary depending on the materials used and the extent of mulch soil coverage. Consequently, the impacts of mulching may differ considerably across production systems, preventing the establishment of reliable guidelines for irrigation water management. The objective of this study is to comprehensively review existing literature that compares mulching versus no-mulching management, aiming to gain a deeper understanding of the effects of mulching on soil evaporation (E_s), crop coefficients (K_c), and actual crop evapotranspiration (ET_{c act}). 58 studies were selected. The impact of mulching was particularly notable in the early crop stages, when the soil is not fully covered. Data in literature shows that plastic films were more effective in reducing K_c than organic materials. However, this effect, while evident during the early crop stages, diminished throughout the rest of the season. Black plastic films were more effective during the early crop stages compared to other colored plastics, particularly relative to the decrease of K_c, but this effect also diminishes during the rest of the season. Building upon these findings, the study provides guidelines for expected reductions in K_c values based on the type of crop, crop stage, and the mulching material most used in each cropping system.

覆盖是一种广泛采用的农艺做法，由于它能有效减少土壤蒸发，因此经常被用作节水策略。然而，效果因所使用的材料和覆盖土壤的覆盖范围而异。因此，覆盖的影响在不同的生产系统中可能有很大差异，从而阻碍了建立可靠的灌溉用水管理准则。本研究的目的是全面回顾比较覆盖与不覆盖管理的现有文献，旨在更深入地了解覆盖对土壤蒸发（E _s）、作物系数（K _c）和实际作物蒸散量的影响（ET _{c 行动}）。选择了 58 项研究。覆盖的影响在作物早期阶段（土壤尚未完全覆盖）尤其显着。文献数据表明，塑料薄膜比有机材料更能有效降低 K _{c 。}然而，这种影响虽然在作物早期阶段很明显，但在整个季节的剩余时间内逐渐减弱。_{与其他有色塑料相比，黑色塑料薄膜在作物早期阶段更有效，特别是相对于 K c}的降低，但这种效果在季节的其余时间也会减弱。基于这些发现，该研究根据作物类型、作物阶段以及每种耕作系统中最常用的覆盖材料，为 K _{c值的预期降低提供了指导。}