A lysimeters study of Chinese wheat and maize varieties: I. The lysimeters-rain shelter facility and the growth and water use of wheat

摘要

Excessive application of N fertilizer contributes substantially to high levels of nitrate (NO3--N) in surface and groundwater on Northern China. A trial was set up to quantify the fate of N within intensive wheat maize rotation system with a view to improve N and water use efficiencies. This paper describes the construction and testing of a lysimeter facility used for this trial. A 44 lysimeter/rain shelter facility was constructed at Shandong Agricultural University (SDAU). Each lysimeter was equipped with a neutron access tube for soil water monitoring and ceramic solution samplers for soil solutions collection. In order to precisely quantify water input, two rain shelters were used to exclude rainwater. The water balance showed that water outputs and inputs agree within 10% for all lysimeters, and that the average water used being 5% less than the total irrigation water supplied was considered as an acceptable error for such large lysimeters. Wheat grown in these devices was consistently higher than those grown with similar fertilizer management in a field located in Ling Xian due to enhanced soil fertility and irrigation in the devices. The facility was shown to be suitable for investigating water and nutrient balances of the root zone