喷灌施肥对露地菜心产量及土壤氮素淋失的影响

Effects of sprinkler irrigation fertilization on the flowering cabbage yield and soil nitrogen leaching

为探明长期连作与喷灌施肥对露地菜心产量及土壤氮素淋失的影响,采用田间小区试验研究了2年间常规施肥(CON)、化肥减量25%(RN)、增量有机肥+化肥减量25%(MRN)对露地菜田土壤氮素淋失、菜心产量的影响。结果表明,菜心全年生长季淋溶液量的变化与灌水定额的高低具有一致性,喷灌灌水定额是影响淋溶液量的主要因素。夏季菜心生长期是总氮淋失的高峰期,占总氮淋失总量的27.12%~32.64%。CON处理与其他处理之间周年总氮淋量存在显著性差异,而菜心产量无显著性差异。2020年MNR处理较CON处理平均增产4.29%,周年平均土壤氮素淋失量降低30.63%。综上所述,减施化肥25%以及增施1/3有机肥处理,可以增加菜心产量、降低土壤氮素淋失量,MRN处理是宁夏引黄灌区露地菜心较好的喷灌施肥管理模式。

In order to investigate the effects of long-term continuous cropping and spraying fertilization on the flowering cabbage yield and soil nitrogen leaching,the effects of conventional fertilization(CON),25%(RN)and incremental organic fertilizer+fertilizer reduction 25%(MRN)on nitrogen leaching and flowering cabbage yield in open field were studied by field experiments in 2 years.The results showed that the change of the amount of dripping solution in the growing season of flowering cabbage was consistent with the irrigation quota,and the irrigation quota was the main factor affecting the amount of dripping solution.The growth period of flowering cabbage in summer was the peak period of total nitrogen leaching loss,accounting for 27.12%-32.64%of total nitrogen leaching loss.There were significant differences in annual total nitrogen leaching amount between CON treatment and other treatments,and there was no significant difference in flowering cabbage yield.In 2020,the average yield of MNR treatment was 4.29%higher than that of CON treatment,and the annual average soil nitrogen leaching amount was reduced by 30.63%,indicating that 25%reduction of fertilizer and 1/3 organic fertilizer application could increase flowering cabbage yield and reduce soil nitrogen leaching.To sum up,MRN treatment is a good management mode of sprinkling irrigation fertilization in open field flowering cabbage production in Ningxia irrigation area.