Improving subsoil fertility through a new technology of continuous in belt and deep incorporation of corn stover

Subsoil often suffers from " organic matter hunger” because of the long term shallow tillage and less organic material returning. The over-tight and poor soil physical properties makes it necessary to find a simple and effective method to break up the plow pan and add organic matter to the hunger soil. In this paper, the three existing deep incorporation methods of corn stover were summarized briefly, and the concept of corn stover enrichment and deep incorporation (CSEDI) was introduced. In CSEDI, the whole-harvested corn straw is collected onto belts, then the special tube plough is used to embed straw into the 20–40 cm depth of subsoil by wind power injection. The soil layer will keep in original order, the following year’s planting would not be disturbed. CSEDI simulation test showed that after straw was embedded into soil for 330 days, the decomposition rate was above 65%, the residual straw became humified and soil organic carbon content was increased by 10%–15%, the arable layer thickness increased from the original 15–18 cm to 30–35 cm. The H/C and hydrophilic ratio of humic acid were also improved. The CSEDI was not found causing the reduction of maize yield in the second year, on the contrary, achieved about 5% of increase than that of traditional cultivation. These results proved that with the CSEDI, the full amount of corn stover could be returned to the field year by year, the alternative belt-corporation of straw made the separated planting and returning come to truth. This method was also proved to be effective to break up the plow pan and increase subsoil organic matter content quickly.