木薯茎秆栽培基质氮变化规律研究  

Change Rule of Nitrogen in Cassava Stalk Cultivation Substrate

作　　者：李光义[1] 余小兰[1] 徐林[1] 张红燕[1] 邹雨坤[1] LI Guang-yi;YU Xiao-lan;XU Lin(Environment and Plant Protection Institute,CATAS / Danzhou Scientific Observing and Experi-mental Station of Agro-Environment,Ministry of Agriculture,P.R.China,Haikou,Hainan 571101)

机构地区：[1]中国热带农业科学院环境与植物保护研究所/农业部儋州农业环境科学观测实验站,海南海口571101

出　　处：《安徽农业科学》2018年第17期68-71,75,共5页Journal of Anhui Agricultural Sciences

基　　金：海南省自然科学基金项目(20163105)

摘　　要：[目的]探讨木薯茎秆栽培基质氮的变化规律。[方法]在未添加外源养分的条件下,以盆栽法对比研究了木薯茎秆栽培基质在种植番茄和不种植番茄2种情况下各形态氮在番茄不同生育期的变化情况。[结果]在番茄整个生育期,"木薯茎秆栽培基质+番茄"的pH为7.48~7.86,"木薯茎秆栽培基质"的pH为7.28~7.88;EC值在幼苗期前从3.28μS/cm急剧上升至1 371.00μS/cm,幼苗期之后几乎保持不变;pH、EC值均在理想栽培基质要求范围内。木薯茎秆栽培基质全氮减少幅度为0.276%~0.281%,木薯茎秆栽培基质仍具有较强的供氮潜力。碱解氮含量相对稳定,营养生长期前,"木薯茎秆栽培基质+番茄"碱解氮高于"木薯茎秆栽培基质",营养生长期后正好相反。铵态氮、硝态氮的大量损失主要发生在番茄营养生长期前;营养生长期后,铵态氮含量保持在35.08~49.93 mg/kg,而"木薯茎秆栽培基质+番茄"硝态氮持续损失直至殆尽,"木薯茎秆栽培基质"硝态氮却有回升,番茄更易吸收硝态氮;矿化氮变化规律与铵态氮、硝态氮变化规律正好相反。氮的转化主要发生在铵态氮、硝态氮和矿化氮之间,但铵态氮、硝态氮的存在会抑制有机氮的矿化。[结论]该研究结果为木薯茎秆作为栽培基质的推广、应用及有机基质栽培养分管理提供了理论依据。[Objective] The aim was to explore the change rule of nitrogen in cassava stalk cultivation substrate. [Method] Under the condition of no adding exogenous nutrient, the change rules of different forms of nitrogen of cassava stalk substrate were studied by pot culture experiment under two conditions of planting tomato and not planting tomato. [Result] In the whole growing period of planting tomato, the pH value of ‘cassava stalk substrate ＋ tomato’ was 7.48-7.86, and the pH of ‘cassava stalk cultivation substrate’ was 7.28-7.88. Before seedling stage, the value of EC increased from 3.28 μS/cm to 1 371.00 μS/cm, and remained almost constant after seedling stage. Both the pH and EC value were within the requirement of ideal substrate. The reducing range of total nitrogen in cassava stalk cultivation substrate was 0.276%-0.281%, and the cassava stalk cultivation substrate still had a strong potential for nitrogen supply. The content of alkali hydrolyzable nitrogen was relatively stable. The alkali hydrolyzable nitrogen of ‘cassava stalk substrate ＋ tomato’ was higher than ‘cassava stalk cultivation substrate’ before the vegetative stage, and after the vegetative stage was just the opposite. Heavy losses of NH 4 ＋-N and NO 3 --N occurred in tomato vegetative stage, afterwards, the content of NH 4 ＋-N kept in 35.08-49.93 mg/kg, the NO 3 --N of ‘cassava stalk cultivation substrate ＋ tomato’ kept losing until exhausted, but the NO 3 --N of ‘cassava stalk cultivation substrate’ picked up, which indicated that NO 3 --N could be absorbed more easily than NH 4 ＋-N. The change rule of mineralized nitrogen was adverse to NH 4 ＋-N and NO 3 --N. The transformation of nitrogen mainly occurred among NH 4 ＋-N, NO 3 --N and mineralized nitrogen. However, the presence of NH 4 ＋-N and NO 3 --N could inhibit the mineralization of organic nitrogen. [Conclusion] The result provides reference for promotion and application of cassava stalk as cultivation substrate as well as organic matrix cultiv

关 键 词：木薯茎秆 栽培基质 氮释放 氮转化 番茄生育期 

分 类 号：S181[农业科学—农业基础科学]