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The leaching and redistribution of nutrients in the surface layer of 4 types of red soils in SoutheastChina were studied with a lysimeter experiment under field conditions. Results showed that the leachingconcentrated in the rainy season (from April to June). Generaily, the leaching of soil nutrients from thesurface layer of red soils was in the order of Ca > Mg > K > NO3-N. In fertilization treatment, the totalamount of soil nutrients leached out of the surface layer in a red soil derived from granite was the highest inall soils. The uptake by grass decreased the leaching of fertilizer ions in surface layer, particularly for NO3-N.Soil total N and exchangeable K, Ca and Mg in the surface layer decreased with leaching and grass uptakeduring the 2 years without new fertilization of urea, Ca(H2PO4)2, KCl, CaCO3 and MgCO3. Ca movedfrom the application layer (0~5 cm) of fertilizer and accumulated in the 10~30 cm depth in the soils studiedexcept that derived from Quaternary red clay. The deficiency of soil exchangeable K will become a seriousdegradation process facing the Southeast China.
The leaching and redistribution of nutrients in the surface layer of 4 types of red soils in SoutheastChina were studied with a lysimeter experiment under field conditions. Results showed that leaching condensed in the rainy season (from April to June). Generaily, the leaching of soil nutrients from the surface layer of red soils was in the order of Ca> Mg> K> NO3-N. In fertilization treatment, the totalamount of soil nutrients leached out of the surface layer in a red soil derived from granite was the highest inall soils. The uptake by grass decreased the leaching of fertilizer ions in surface layer, particularly for NO3-N. Total N and exchangeable K, Ca and Mg in the surface layer decreased with leaching and grass uptaked during the 2 years without new fertilization of urea, Ca (H2PO4) 2, KCl, CaCO3 and MgCO3. Ca moved from the application layer (0-5 cm) of fertilizer and accumulated in the 10-30 cm depth in the soles studiedexcept that derived from Quaternary red clay. The de ficiency of soil exchangeable K will become a serious degradation process facing the Southeast China.