摘要
以灰潮土为对照 ,研究了华中地区 3种已明显发生酸化的土壤在施用碳酸钙前后各形态锰的变化情况。结果表明 ,已酸化的红壤、棕红壤和黄褐土施用碳酸钙降低了土壤酸度 ,土壤交换态锰随 pH值上升而降低 ,其降幅分别为 42 % ,49%和 39% ;其它形态锰的增减随各土而异 ,残留态锰较稳定 ,变幅小。作为对照 ,灰潮土虽与前 3种已酸化土壤一样种植过多茬作物 ,但其交换态锰含量仍甚微。无论是否施用碳酸钙 ,在灰潮土的交换态锰、碳酸钙结合态锰和易还原态锰 3种形态锰中 ,易还原态锰占 80 %以上 。
Studies were conducted to assess the transformation of various Mn forms in 3 of acidified soils in the Central China before and after application of CaCO 3 contrasted to a kind of calcareous alluvial soil The results showed that soil acidity decreased in the acidified red soil, brown red soil and yellow cinnamon soil by applying of CaCO 3 With decrease of pH, the content of exchangeable Mn (EXC Mn) increased by 42%, 49% and 39% in the above soils, respectively, while that of easily reducible Mn (ERO Mn) decreased on the contrary The contents of calcium carbonate bound Mn (CARB Mn), organic matter bound Mn (OM Mn) and reducible Mn (RO Mn) only changed slightly, and residual Mn (Res Mn) altered more lightly In the calcareous alluvial soil, the content of EXC Mn was rather small, ERO Mn was main part of active Mn, and CaCO 3 application had little influence upon other forms of Mn Due to no correlation between EXC Mn and CARB Mn, they were independent to each other, i e , they were different bound forms in soil surface EXC Mn was a kind of exchangeable cation which was adsorbed by negative charge of soil CARB Mn was occluded by easily dissolved oxides in acidic soil or was adsorbed by carbonate precipitates in calcareous alluvial soil It was a kind of intermediate between EXC Mn and ERO Mn and could easily transform into ERO Mn After applying CaCO 3 to acidified soil, in which EXC Mn would be changed into CARB Mn, even into ERO Mn, that was the effect of applying CaCO 3 to overcome toxicity of EXC Mn in growth of crops
出处
《植物营养与肥料学报》
CAS
CSCD
北大核心
2001年第3期325-330,共6页
Journal of Plant Nutrition and Fertilizers
基金
湖北省自然科学基金项目 ( 99J117)
农业部亚热带土壤资源环境重点开放实验室资助
关键词
酸化土壤
锰分级
锰形态转化
施用碳酸钙
acidified soil
Mn fractionation
transformation of Mn forms
application of CaCO 3
