Soil moisture distribution, erosion and nitrogen availability in some alley cropping systems.
1992
Umali C.G.
The sequential soil moisture data were used to validate the WATBAL subroutine of the Crop Environment Resource Synthesis (CERES-Maize) model. In this validation, agreement between the predicted and the observed soil moisture values was relatively satisfactory. This was also true for runoff and sedimentation only after some modifications done with the model. Predictions for soil nitrogen dynamics were also examined and found to agree with the observed data. Failure to simulate dry matter yields was suspected to result from erroneous genetic coefficients, faulty parameter estimates and rate constants, and from the inability of the model to consider the effects of weeds and insect (corn borer) infestation. Some other opportune time, it is worth trying to further modify the CERES Maize model to consider these and other ecological effects on maize growth and development. With optimum amount and distribution of rainfall and soil moisture, corn growth and performance were not adversely affected except in the later part of the growing season when a strong typhoon and probably corn borer infestation considerably reduced corn yield. The remarkable soil conserving ability of Desmanthus hedgerows together with mulch and zero tillage was evidenced by the reduction of runoff by 1/2 using hedgerow alone (T2), by 3/4 using both hedgerow and mulch (T3), and by 9/10 using hedgerow and mulch on no-tilled corn plots (T4).
显示更多 [+] 显示较少 [-]