不同水肥耦合对西芹收获期土壤硝酸盐累积的影响

Effects of water-fertilizer coupling on accumulation of soil nitrate in celery harvest period

摘要:

采用三因素五水平二次通用旋转组合设计，研究了冀西北高寒半干旱区不同水肥耦合对旱棚西芹收获期0 ~ 40 cm土层中硝酸盐累积的影响。结果表明：①在高中低不同水肥处理组合中，较高肥在较高水下可减少0 ~ 40 cm土层土壤硝酸盐的累积，较高肥在较低水下可使土壤硝酸盐相对累积增多；综合因子效应分析表明：随着单因子水平增加，N、P和水（W）对0 ~ 40 cm土层土壤硝酸盐的相对累积依次表现为：增加、不明显和减少。②三因子其他组合下，0 ~ 40 cm土层土壤硝酸盐的累积效应表现为： 在PW一致下，随N量的增加而增加；在NP一致下，随灌水量增加而减少；在NW一致下，随施P量增加而有不确定性。各处理硝酸盐的累积均随土壤深度的增加而增加，体现了水对土壤硝酸盐淋洗的特点。

Abstract:

With 3 factors and 5 levels of the secondary regression of orthogonal block design, artificial water control experiments in the shed of rain-free condition were conducted in the semiarid cold region of northwest of Hebei to analyze the effects of different water-fertilizer coupling on soil nitrate accumulation (0 ~ 40 cm depth) in celery harvest period. The results showed that: ①To high, moderate, low water-fertilizer coupling, higher fertilizer and higher water treatment reduced accumulation of soil nitrate while higher fertilizer and lower water treatment accumulated more soil nitrate. With the increase of single factor, the effects of N, P and W on soil nitrate were increasing, unobvious and decreasing respectively. ②Under three factor coupling, soil nitrate increased with N increases under the same P and W level; nitrate decreased with W increases under the same N and P level; while nitrate was uncertain with P increases under the same N and W level. Nitrate accumulation increased with depth in all treatments, which shows the leaching effect of water on soil nitrate.