[Objective] This study aimed to investigate the effects of phosphine on germination and physiological characteristics of rice seeds. [Method] Simulation envi- ronments were conducted to study the effects of high-level phosphine on germination status and physiological characteristics of rice seeds and explore the early environ- mental and ecological effects of phosphine on rice growth in phosphorus cycle of paddy field. [Result] Experimental results showed that the increase of phosphine con- centration in the environment resulted in the decrease of germination rate and ger- mination potential by 11.11% and 19.71%, respectively. In addition, the activities of catalase （CAT） and peroxidase （POD） were reduced to 94.35% and 92.61%, respec- tively; the content of malondialdehyde （MDA） was maximally increased by 29.11%, indicating that both germination potential and growth condition of rice seeds were in- hibited under conditions of high-level phosphine. [Conclusion] This study provided theoretical basis for investigating the effects of phosphine on germination of rice seeds under natural environment.
以模拟电子垃圾拆解区污染土壤中的多溴联苯醚(PBDEs)为研究对象,采用室内模拟的方法,考察了臭氧浓度的上升及光照条件、温度和土壤pH值等环境因素对土壤中PBDEs自然降解过程的影响.研究结果表明:臭氧浓度的升高能明显促进PBDEs的自然降解,且臭氧浓度越高BDE-209的降解率越高,随着土壤深度增加,BDE-209去除率则相应降低,10 mg·L-1的臭氧在2 h内对深层土壤中BDE-209的去除率可达99%.光照强度为1.0 m W·cm-2的持续紫外光照条件下,土壤中BDE-209的降解现象较为明显,且光降解速率随光强的增强而增大.40℃的夏季地面高温及pH=9.0的弱碱性土壤均有利于PBDEs的自然降解.此外,PBDEs的降解过程是逐步脱溴的过程.PBDEs的降解过程既包括了BDE-209的降解,也包括了中间产物(BDE-28、BDE-47、BDE-99、BDE-100、BDE-153、BDE-154和BDE-183)的降解.当BDE-209去除率达到一定程度且中间产物逐渐积累达一定量时,中间产物的降解反应逐渐成为主导反应,导致PBDEs总量逐渐降低.
