大气O3浓度升高对麦季土壤和植株氮磷钾的影响

Effects of elevated atmospheric O_3 on N,P,and K concentrations in soil and wheat plant during wheat growth season

以江都稻/麦轮作系统O3-FACE(ozone-free air concentration enrichment)为试验平台,研究了高浓度O3(比周围大气高50%)对麦季土壤和植株N、P、K含量的影响。结果表明:在小麦整个生长期,高浓度O3处理下,土壤NH4+-N、NO3--N和速效K含量分别降低了5.7%、3.6%和3.0%,土壤速效P含量提高了26.3%(P<0.05)。经高浓度O3处理后,小麦植株在拔节期体内K含量增加了28.4%(P<0.01);成熟期小麦植株各器官内N含量均降低,麦粒中P和K含量分别增加了6.5%和4.2%;指出大气O3浓度升高在整个小麦生长期内会促进小麦植株对N、K的吸收,同时提高小麦籽粒中K、P的含量,但降低了成熟期小麦植株N含量。

Taking the rice/wheat ozone free-air concentration enrichment（O3-FACE） system in Jiangdu County of Jiangsu Province as a platform,this paper studied the effects of elevated atmospheric O3（target at 50% above ambient） on the N,P,and K concentrations in soil and wheat plant during wheat growth season.In the whole growth season of wheat,the concentrations of soil NH4＋-N,NO3--N,and available K under elevated O3 decreased by 5.7%,3.6% and 3.0%,respectively,while the soil available P concentration increased by 26.3%（P0.05）,compared with those under ambient O3.Under elevated O3,the K concentration in wheat plant at jointing stage increased by 28.4%（P0.01）,the plant N concentration at maturing stage decreased,while the P and K concentrations in wheat grain increased by 6.5% and 4.2%,respectively.Our results suggested that elevated atmospheric O3 could promote the N and K uptake by wheat plant in its whole growth period,increase the K and P concentrations in wheat grain,but decrease the N concentration in wheat plant at maturing stage.