摘要
为明确滨海盐碱环境下盐肥耦合对续随子荧光特性及土壤微生物的影响,通过正交试验设计进行田间试验,研究了不同土壤盐分下续随子盐肥耦合效应。结果表明:①2.1~3.5g/kg的土壤盐分可促进续随子生长,盐分增大,生长受到抑制。增施氮肥可缓解盐分胁迫对植株生长的抑制作用,随着施氮量的增加,生物量及株高呈现先增加后下降的趋势;②土壤盐分增大,续随子叶片净光合速率(P_n)、初始荧光(F_o)、最大荧光(F_m)、PSⅡ实际光化学效率(Φ_(PSⅡ))、幼苗叶片光化学荧光猝灭系数(qP)均降低。增施氮肥可显著提高各项指标,以75 kg·hm^(-2)(N_2)、150 kg·hm^(-2)(N_3)水平为佳。③滨海盐碱环境下土壤养分及土壤微生物养分随盐分的增加而下降。增施氮肥后,在75 kg·hm^(-2)(N_2)、150 kg·hm^(-2)(N_3)水平下,土壤全氮、有机质含量以及土壤徽生物氮、碳含量呈现显著增加的趋势。④在盐碱环境下增施氮肥可使土壤微生物物种丰富度指数(H)增大,优势度指数(Ds)减小。由此说明在盐碱环境下增施氮肥,其盐肥耦合作用可促进续随子的生长、提高光合荧光性能、增加土壤养分以及土壤微生物养分,提高土壤微生物多样性,对改善盐碱生态环境有积极的作用。
A field experiment based on the coastal saline soil was carried out to study the coupling effect of salt and fertilizer application on the chlorophyll fluorescence of Euphorbia lathyris L. and microbiological characteristics of softs. The resuhs were as follows ： （i） Compared to other salt concentration of soil, there were better fresh weight and plant height of Euphorbia lathyris L. when the salt concentration of soil was 2.1 - 3.5 g/kg. The fresh weight and plant height decreased with the increase of salt concentration of soil. Increasing nitrogen fertilizer could alleviate the salt stress on plant growth. With the increase of amount of nitrogen fertilizer, the fresh weight and plant height showed first increased and then decreased trend. （ii） The net photosynthetic rate（Pn ）, minimal fluorescence（ Fo）, maximum fluorescence（ Fm ）, ΦPSⅡ and photochemical quench （qP） of Euphorbia lathyris L. all decreased with the increase of soil salinity. After the application of nitrogen fer- tilizer, various index data all increased significantly under the level of N2 and N3. （iii） The soil nutrient and soil microbial nutrient de- creased with the increase of soil salinity. After the application of nitrogen fertilizer, soil total nitrogen content and soil organic matter content, soil microbial carbon content and soil microbial N content increased significantly under the level of N2 and N3. （iv） With the increase of ni- tregen in coastal saline soil, species richness index（H） was significantly increased, dominance index（Ds） decreased. In coastal saline soil, the coupling effect of salt and fertilizer can promote the growth of the Euphorbia lathyris L. , increase the photosynthesis and chlorophyll fluo- rescence of plant, increase the soil nutrient and soil microbial nutrient, and improve the soil microbial diversity. So, the increasing of nitrogen in coastal saline soil has positive effect on improving the ecological environment of coastal saline soil.
出处
《西南农业学报》
CSCD
北大核心
2016年第8期1918-1923,共6页
Southwest China Journal of Agricultural Sciences
基金
江苏省农业科技自主创新资金(CX(14)2046)
江苏苏北科技发展计划(BN2014056)
关键词
续随子
盐肥耦合
叶绿素荧光
光合作用
土壤微生物
Euphorbia lathyris L.
Coupling effect of salt and fertilizer
Chlorophyll fluorescence
Photosynthesis
Microorganism of soil
