设施黄瓜土壤化学性质对施肥时间的动态响应

Responses of Soil Chemical Properties to Fertilization in Cucumber Greenhouse

为了解施肥对设施黄瓜土壤化学性质的动态影响,为设施种植施肥提供理论支持,以湖北省荆门市设施蔬菜大棚基地为研究对象,共设2个试验棚,分别使用不同种肥料,研究拔园后剖面土及施肥后14 d内土壤化学性质的变化。结果表明:大棚内土壤表层酸化显著,在土壤深度为0~100 cm,养分含量随土壤深度的增加逐渐降低。施肥后土壤微生物量碳(Soil microbial biomass carbon,SMB-C)、土壤微生物量氮(Soil microbial biomass nitrogen,SMB-N)在14 d的观测周期内,棚A、B内呈现出的变化趋势一致,且均在施肥后第2天时达到第1个高峰(B棚SMB-C在施肥第3天时达到最大值);铵态氮含量亦是施肥2 d时2个棚内的含量最高,且铵态氮、硝态氮含量在整个观测期内呈现先增加后降低的变化趋势;土壤碱解氮的含量变化与施加肥料存在一段时间内的动态关系,但随施肥时间的加长,碱解氮仍会恢复到未施肥的状态。综合几种土壤化学性质的变化规律可见,施肥后第2天肥效最显著。通过观察14 d的监测结果可发现,14 d后各化学性质逐步恢复到未施肥时的水平,下一步可加长监测期,为施肥周期的合理制定提供理论依据。

In order to invest the dynamic effects of fertilization on the chemical properties of cucumber soils, and provide theoretical support for fertilization in greenhouse, two vegetable greenhouses were set up as research objects, which were located in Jingmen City, Hubei Province. In the experiment, different kinds of fertilizers were used to study the changes of soil chemical properties within 14 days after fertilization and profile soil. The results showed that soil surface acidification was significant in the greenhouse, and the nutrient content gradually decreased with the increase of soil depth in the range of 0-100 cm. Soil microbial biomass carbon(SMB-C), Ammonium nitrogen and Soil microbial biomass nitrogen(SMB-N) showed the same trend in the observation period of shed A and B. And they all reached the first peak at the 2 nd day after fertilization(SMB-C in B greenhouses reached the first peak at the 3 rd day after fertilization). The content of ammonium nitrogen were the highest after two days of fertilization in the two greenhouses, and the content of ammonium nitrogen and nitrate nitrogen increased first and then decreased during the whole observation period. It could be seen that the fertilizer effect was the most significant on the 2 nd day after fertilization by observing the changes of soil chemical properties. There was a dynamic relationship between the change of soil alkaline nitrogen content and fertilizer application for a period of time, but with the increase of fertilization time, it would return to the state of non-fertilization. It was found that the chemical properties were gradually recovered to the level of non-fertilization by observing the monitoring results for 14 days. Therefore, the next monitoring period could be lengthened to provide a theoretical basis for the rational formulation of the fertilization cycle.