施用猪粪后果园土壤中养分含量的动态变化

【目的】研究猪粪施入土壤后,土壤中各养分含量的动态变化,为荔枝生产合理施用粪肥提供参考。【方法】在荔枝果园土壤中添加不同用量猪粪(w为0、1%、2%和4%)进行培养试验,探讨土壤中的大、中和微量元素养分含量在360 d的动态变化。【结果】即使土壤中有效N、P、K、Ca和Mg含量缺乏,Mn、Cu和Zn含量中等,以1%用量施用猪粪后,除交换性Ca和Mg含量达中等水平外,其他养分可立刻达到丰富水平。猪粪用量越高,土壤碱解N维持在丰富水平的时间越短且降幅越大,但有效P、速效K、交换性Ca、Mg以及有效Fe、Mn、Cu、Zn含量显著提高(P0.05),而且除速效K和有效Fe外的其他养分含量波动越大,供应稳定性越差。【结论】猪粪是良好的作物养分来源,但荔枝生产上用量不宜超过1%,即15 t·hm–2,配合施用的各种化肥(如N肥和K肥)也应相应减少或甚至不施P肥和Fe、Mn、Cu、Zn等微肥。

Dynamic changes of nutrient contents in orchard soil after pig manure application

Objective Dynamic changes of nutrient contents in soil applied with pig manure were studied with the aim to offer guideline for reasonable manure application in litchi production.Method The variations of macro-, secondary and micro-nutrients in soils applied with different contents (w=0, 1%, 2% and 4%) of pig manure were investigated during 360 days of incubation test.Result In soil deficient of available N, P, K, Ca, Mg and medium of available Mn, Cu and Zn, after pig manure was applied at the content of 1%, the contents of all soil nutrients immediately reached abundant levels, except that exchangeable Ca and Mg contents reached medium levels. As the manure application rate increased, soil alkali-hydrolyzable N maintained at rich level with shorter duration and then decreased more sharply, while soil available P, K, Ca, Mg, Fe, Mn, Cu and Zn contents significantly increased (P < 0.05). Moreover, soil nutrient (except available K and Fe) contents had larger fluctuations, leading to lower stability of soil nutrient supply.Conclusion Pig manure is a quality nutrient source for crop and is recommended to be applied at the rate of no more than 1%, namely 15 t·hm^-1 in litchi production. Simultaneously, the application rates of inorganic N and K fertilizers should be reduced, and some other inorganic fertilizers such as P, Fe, Mn, Cu and Zn should be withdrawn.