论文部分内容阅读
采用正交试验设计,研究了微喷灌条件下,设施菜地土壤水分含量和硝态氮含量对水肥耦合的响应规律。结果显示:(1)灌溉施肥后,0~60 cm土层土壤含水量下降。青菜成熟期时,土壤含水量高于幼苗期和旺长期。(2)在青菜的不同生育时期,各水肥因子对土壤含水量的影响主次程度不同,施肥量、灌水量和肥料配比对土壤含水量的影响较大,灌水周期对土壤含水量的影响相对较小。(3)土壤硝态氮含量受灌溉施肥的影响波动幅度随土壤深度的增加而减缓。灌水后,0~10 cm土层硝态氮含量最高,达到380.53 mg/kg。(4)高肥低水和低肥高水的水肥耦合方式均会造成表层土壤硝态氮积累,引起氮肥流失。各水肥因子中,施肥量对土壤硝态氮含量影响最大,灌水量和肥料配比的影响次之,灌水周期对土壤硝态氮含量的影响最小。研究结果证实在微喷灌条件下,通过水肥优化耦合可以有效避免氮肥淋失。
Orthogonal experimental design was used to study the response of soil water content and nitrate nitrogen content to water and fertilizer coupling in micro-sprinkler irrigation. The results showed that: (1) Soil water content in 0 ~ 60 cm soil layer decreased after irrigation and fertilization. Vegetable maturity, the soil moisture content is higher than the seedling and Mongolian long-term. (2) At different growth stages of vegetables, the effect of different fertilizers on soil water content is different from primary to secondary. Fertilizer amount, irrigation amount and fertilizer proportion have great influence on soil water content. The effect of irrigation cycles on soil water content Relatively small. (3) The effect of irrigation and fertilization on soil nitrate nitrogen content fluctuated with the increase of soil depth. After irrigation, the nitrate content in 0 ~ 10 cm soil layer was the highest, reaching 380.53 mg / kg. (4) The combination of water and fertilizer with high fertilizer, low water and low fertilizer and high water will all cause the accumulation of nitrate nitrogen in the surface soil and cause the loss of nitrogen fertilizer. Among all water and fertilizers, the amount of fertilizer had the strongest effect on soil nitrate nitrogen content, followed by irrigation amount and fertilizer proportion, and irrigation period had the least effect on soil nitrate nitrogen content. The results show that under the condition of micro-sprinkler irrigation, the coupling of water and fertilizer can effectively avoid the leaching of nitrogen fertilizer.