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本文研究了冲积性水稻土的锰素特征与小麦缺锰的土壤条件。结果表明:冲积性水稻土因受种稻影响,与冲积土比,全锰和有效锰特别是活性锰明显降低,而代换锰在活性锰中有较大比率;土壤剖面内全锰和活性锰随深度的增加而增加;水旱轮作造成耕层土壤锰的淋失是本区小麦缺锰的主要原因。但对于pH较低的土壤,活性锰即使低于15ppm,小麦也不会缺锰;石灰性、轻质和水旱轮作是小麦缺锰的主要土壤条件。对于冲积性水稻土,若没有使pH升高的因素出现,小麦大面积发生缺锰症的可能性不大。此外,还发现国内常用的有效锰临界指标在本区土壤上偏高。
In this paper, the characteristics of manganese in alluvial paddy soils and soil conditions for wheat deficient in manganese were studied. The results showed that compared with alluvial soil, the alluvial paddy soil had a significantly lower ratio than alluvial soil, total manganese and available manganese, especially active manganese, while substitutional manganese had a larger ratio in active manganese; total manganese and activity in soil profile Manganese increased with depth; the leaching of manganese from topsoil was the main reason for the lack of manganese in this area. However, for low pH soils, even less than 15 ppm of active manganese will not be deficient in wheat; and the calcareous, light and drought-tolerant rotations are the major soil conditions for manganese deficiency in wheat. For alluvial paddy soil, if there is no factor that causes the increase of pH, it is unlikely that wheat will be susceptible to Mn deficiency in a large area. In addition, it is also found that the commonly used effective manganese threshold in China is high in the soil of this area.