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Burnett指出,改造土壤剖面任一部分的耕作措施,均可看作是某种形式的土壤剖面改良。但剖面改良一般是指带或不带化学或物理改良剂的耕深超过普通深度的耕作措施(Unger,1979)。本文所讨论的剖面改良是指深度在0.25m以上的犁耕、耕松心土、垂直松土、全剖面破碎与混合、挖沟以及设置心土隔层等措施。剖面改良总的目的是通过提供更有利于根系生长发育的土层,来提高作物产量。一般说来,土壤中限制根系生长发育的因素如果有所改善,剖面改良则将认为是成功的。 Unger将需要通过剖面改良来予以解决
Burnett pointed out that the tillage measures to rebuild any part of the soil profile can be considered as some form of soil profile improvement. However, profile improvement generally refers to tillage practices where plow depths exceed normal depth with or without chemical or physical aids (Unger, 1979). The section improvement discussed in this paper refers to plowing, plowing loose soil, vertical loosening, full section crushing and mixing, trenching and the setting of heart-soil interbeds at a depth of 0.25m or more. The general purpose of profile improvement is to increase crop yields by providing soil layers more conducive to root growth and development. In general, improvements in root growth and development in the soil, if improved, will be considered successful. Unger will need to be resolved by profile improvements