大气O_3升高对小麦根际土壤微生物量和氮素转化酶活性的影响  

Influence of Elevated O_3 and Different Wheat Cultivars on Soil Enzymes Involving in Nitrogen Transformation

作　　者：陈伟[1,2] 皇甫倩华[1] 孙从建 张丽莉[2] 武志杰[2] 

机构地区：[1]山西师范大学,山西临汾041000 [2]中国科学院沈阳应用生态研究所,辽宁沈阳110016

出　　处：《土壤通报》2017年第3期623-630,共8页Chinese Journal of Soil Science

基　　金：国家自然科学基金项目(41101242;41601317)资助

摘　　要：通过开放式臭氧浓度升高试验平台(FAOE)对扬麦16(臭氧耐受品种)和烟农19(臭氧敏感品种)根际土壤氮转化相关酶活性进行研究。结果表明:臭氧熏蒸5年后,小麦根际蛋白酶活性未发生显著变化;敏感品种根际脲酶活性增高4.01%;氨氧化酶活性在敏感和耐受品种根际土壤中分别提高19.38%和203.66%,土壤NH_4^+和NO_3^-显著升高,但微生物量氮显著下降;硝酸还原酶和亚硝酸还原酶活性分别呈现下降和升高的趋势,这种变化在臭氧敏感品种土壤中更显著。冗余分析表明,全氮、臭氧和pH是显著影响这5种酶活性的最主要因素。试验的结果表明,在大气臭氧浓度升高条件下,小麦根际氮循环会在酶的调节下发生变化,可能会增加土壤氮素以温室气体N_2O和硝酸盐形式损失的风险,且臭氧敏感品种根迹土壤变化更显著。Taking rhizosphere soil from two different wheat （Triticum aestivum L.） cultivars Yannong 19 （ozone sensitive） and Yangmai 16 （ozone relatively sensitive） as tested materials, this paper studied the enzymes activities involving in nitrogen transformation through free-air ozone enrichment （FAOE） system. The results showed that under elevated ozone （eO3） concentration, protease activity had no significant change, while urease activity increased by 4.01% at O3 sensitive wheat rhizosphere soil, ammonium oxidase activity increased significantly at O3 sensitive and relatively sensitive cultivars by 19.38% and 203.66%, respectively. In accord with urease and ammonium oxidase, soil NH4＋ and NO3- increased significantly but microbial biomass nitrogen （MBN） decreased. The activities of nitrate reductase and nitrite reductase decreased and increased, respectively. Redundancy analysis （RDA） showed that total nitrogen, O3 and pH were the most important factors to influence the activities of five enzymes. Our results indicated that under elevated O3, nitrogen cycling at wheat rihzosphere soil could be altered because of changed enzymes activities. These changes may increase the risk of nitrogen loss through ammonia volatilization and nitrate leaching, and this phenomenon was more obvious at O3 sensitive wheat cultivar.

关 键 词：开放式臭氧浓度升高试验平台 氮转化酶 不同小麦品种 裂区分析 

分 类 号：S154.2[农业科学—土壤学] S512.1[农业科学—农业基础科学]