The Study On Restorial Effect Of Several Fertilization Structures On Eroded Red Soils From Various Parent Materials

In order to understand the restorial effect of different fertilization structures on eroded red soils from various parent material, A pot experiment was carried out by using4representative eroded red soils developed from various parent materials in Southern China, i. e., homogeneous horizon red soil (J) and reticulate horizon red soil (W)of Quaternary Red Earth, weathered product of granite (H) and weathered product of, slate (B), as the tested soil. A pot experiment was conducted to investigate the restorational effects of Chemical fertilizer (NPK), NPK+Organic fertilizer (NPKM), NPK+Soil conditioner R2(NPKR2)on the eroded red soil which developed from different parent materials. It was aimed at providing a scientific basis and technical support for restoring eroded red soils. The main results are as follows.(1) All fertilization treatments could increase the content of alkali-hydrylizable N, available P, readily available K and organic matter contents in the tested soil to varied extent. Of which, Treatment NPKM could increase alkali-hydrylizable N and organic matter contents in the soil most significantly, and treatment NPKR2increased the available P and readily available K contents in the soil most significantly. All fertilization treatments increased the biomass of each season crop, and the biomass output of treatment NPKM was the highest. however, the biomass output of different season crop could not keep stable. biomass output of blank control kept downward trend. All the above results indicated that it would be a long-term project to repair eroded red soil and make crops yield stable and increase slably.(2) Different fertilization treatment had varied effect on improving soil acid. All fertilization treatments could inhibit hydrolysis of unexchangable Al3+in the soil, decrease the content of exchangeable acid and exchangeable Al3+in the soil, increase ApH of acid soil, and improve soil acid. Of which, T treatment NPKR2had the most significant effect. In addition, Treatment NPKR2also increased pHBC of the soil significantly. It was an effective technical measure to improve soil acidification.(3) Response ability of different eroded red soils to various fertilizations varied differently. Response of granite red soil and slate red soil were the most sensitive. All fertilization treatment could decrease the acid of granite red soil and slate red soil significantly.Treatment NPK and NPKM could increase the contents of exchangeable acid and exchangeable aluminum in reticulate horizon red soil (W) and homogeneous horizon red soil(J), decrease pH of soil and accelerate soil acidification.(4) All fertilization treatment could increase CEC and ECEC of the soil, and enhance the buffering property and the ability of preserving fertility of the soil. Of which, the Effect of treatment NPKR2was the best also.(5) Treatment NPKR2could increase the contents of sand and silt and decrease the content of clay in the soil significantly. However, treatment NPKM could increase the content of clay in the soil. Treatment NPKM increased the anti-erosion ability significantly,and, treatment NPKR2might aggravate soil erosion.