Spatial distribution of soil organic carbon after patchy applications of farmyard manure and its changes over time

摘要

Field studies on spatial distributions of soil organic carbon(SOC)after patchy application on alluvial soils of matured cow farmyard manure were carried out.A sampling network was created using GPS equipment,samples were collected at three soil depths.The data were analyzed using geostatistics generating kriging maps of SOC distributions.The results showed that shortly after manure applications,the SOC of the fertilized spots reached 2.12 % in the top soil(30 cm)and sharply dropped underneath.Two years later,the SOC contents 1.47-1.69 % were quite similar along depth suggesting a significant leaching downwards,bellow 90 cm.Kriging method permitted high precision results between the sampling points and provided a base for improvement of manure application management.Significant leaching of SOC down soil profile was observed only on sandy alluvial soil.