Abstract:

Abstract：【OBJECTIVE】Review the principles, methods and application abroad of the soil productivity model (PI), investigate its suitability and possibility of modification in Song Nen Black Soil Region in Northeast China. 【METHOD】Base on the systematic introduction of PI, the paper take Song Nen black soil region in Northeast China as study area，seventeen soil profiles in North-East black soil region were chosen, three different models: Surface soil layer estimate (CI), Productivity index model (PI) and modified productivity index model (BPI) were used based on physico-chemical properties of soil profile; finally, simulated results were compared with crop yield of these soil profiles.【RESULTS】The results show: (1)the discrepancy of calculated index was close for CI model, it can not help to distinguish soil productivity between different soil; but the discrepancy were obvious for PI and BPI model, it is good for distinguishing soil productivity between different soil. (2) Correlation between productivity index and corn yield in common years were analyzed, The highest Determination coefficient with R2=0.6774(P<0.01) was appeared in BPI model, followed by PI model with R2=0.3285(P<0.05), the lowest was appeared in CI model (P>0.05). (3) PI model over-estimate the result for those soil with low organic content, after import organic factor in to the model, BPI got a better estimation for black soil.【CONCLUSION】In conclusion, PI model take upper 100cm horizon soil as estimated object of soil productivity, the estimated accuracy is better than CI model. If organic factor was considered, the BPI model got a better estimation than PI model. Besides the organic factor, whether the other soil physico-chemical properties is helpful to improve accuracy for BPI in North-East black soil region, it need research further in future.