Dispersive soils limit crop growth and significantly impact world food production. Although numerous reviews have examined soil dispersion, many focus on irrigated systems and fail to differentiate the approaches required for rainfed agriculture. This review seeks to fill this gap by focusing on the impact, identification and management of dispersive soils in rainfed areas. Dispersive soils can have large impacts on crop production because of their adverse physical, chemical and biological effects, with this impact particularly large in rainfed systems where irrigation water is unavailable to supplement crop water supply and assist with amelioration. However, the identification of these soils is challenging and tests that can reliably relate soil characteristics to crop performance are lacking. Recent work has found that first identifying consistently lower yielding locations (using yield mapping or proximal/remote sensing) and then using traditional soil testing to identify the potential cause/s of the yield loss may be a promising approach, although this requires refinement. Knowledge of the type of dispersive soil (e.g., saline/non-saline, acidic/alkaline/neutral) and where constraints occur in the profile (surface or subsoil) must also be determined during identification as this will affect management approaches, particularly where multiple constraints need to be treated together to achieve yield increase. Improved understanding of how to economically use ameliorants and combine them to achieve maximum benefit in the presence of multiple constraints is needed. Greater appreciation of how to use agronomic management to improve crop growth in the presence of dispersive behaviour is also likely to increase profitability in rainfed systems where amelioration is often impractical or uneconomical. Dispersive soils are a major challenge for rainfed cropping, and so the refinement of our management approach can help improve profitability and productivity.

中文翻译：

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雨育种植系统中分散土壤的影响、识别和管理

分散的土壤限制了作物的生长，并显着影响了世界粮食生产。尽管许多评论都研究了土壤扩散，但许多评论侧重于灌溉系统，而未能区分雨养农业所需的方法。本次审查旨在通过关注雨养地区分散土壤的影响、识别和管理来填补这一空白。由于其不利的物理、化学和生物效应，分散性土壤会对作物生产产生重大影响，这种影响在雨养系统中尤为明显，因为灌溉水无法补充作物供水并帮助改善状况。然而，这些土壤的识别具有挑战性，并且缺乏能够可靠地将土壤特征与作物性能联系起来的测试。最近的工作发现，首先确定始终较低的产量位置（使用产量绘图或近端/遥感），然后使用传统的土壤测试来确定产量损失的潜在原因可能是一种有前途的方法，尽管这需要改进。在识别过程中还必须确定分散土壤的类型（例如，盐分/非盐分、酸性/碱性/中性）以及剖面中出现限制的位置（地表或底土），因为这会影响管理方法，特别是在多个需要一起处理制约因素以实现产量增加。需要更好地了解如何经济地使用改善剂并将它们结合起来以在存在多种限制的情况下实现最大收益。在存在分散行为的情况下，更多地了解如何使用农艺管理来改善作物生长，也可能会提高雨养系统的盈利能力，在这些系统中，改善往往不切实际或不经济。分散土壤是雨养作物面临的主要挑战，因此改进我们的管理方法有助于提高盈利能力和生产力。