简介:Cadmium(Cd)ishighlytoxictoplants,animals,andhumans.Limitedinformationisavailableontheroleofnitricoxide(NO)and/or24-epibrassinolide(EBR)inresponseofplantstoCdstress.Inthisstudy,ahydroponicexperimentwasperformedtoinvestigatetheeffectsofNOand/orEBRonpeanutplantssubjectedtoCdstress(200μmolL-1)withsodiumnitroprusside(SNP,anexogenousNOdonor)(250μmolL-1)and/orEBR(0.1μmolL-1)addition.TheresultsshowedthatCdexposureinhibitedplantgrowth,andthisstresswasalleviatedbyexogenousNOorEBR,andespeciallythecombinationofthetwo.TreatmentwithCdinhibitedthegrowthofpeanutseedlings,decreasedchlorophyllcontent,andsignificantlyincreasedtheCdconcentrationinplants.Furthermore,theconcentrationofreactiveoxygenspecies(ROS)markedlyincreasedinpeanutseedlingsunderCdstress,resultingintheaccumulationofmalondialdehyde(MDA)andprolineinleavesandroots.UnderCdstress,applicationsofSNP,EBR,andespeciallythetwoincombinationsignificantlyreducedthetranslocationofCdfromrootstoleaves,increasedthechlorophyllcontent,decreasedtheconcentrationsofROS,MDA,andproline,andsignificantlyenhancedtheactivitiesofsuperoxidedismutase(SOD),peroxidase(POD),andcatalase(CAT)inpeanutseedlings.ExogenousNOand/orEBRalsostimulatedtheactivitiesofnitratereductase(NR)andnitricoxidesynthase(NOS)andincreasedthecontentsofantioxidants,suchasascorbicacid(AsA)andreducedglutathione(GSH).Furthermore,exogenousNOand/orEBRenhancedCdaccumulationinthecellwallandthusdecreasedCddistributionintheorganellesintheroots.Theconcentrationsofcalcium(Ca),iron(Fe),magnesium(Mg),andzinc(Zn)werealsoregulatedbyexogenousNOorEBR,andespeciallybythetwoincombination.TheseresultsindicatedthatSNPandEBR,aloneandparticularlyincombination,canmitigatethenegativeeffectsofCdstressinpeanutplants.
简介:近年来,废弃矿山生态环境问题越来越受到国家的重视,废弃矿山生态恢复逐渐发展为我国城市生态环境建设的重要内容之一,而区域地形测量则是生态恢复的基础。影像全站仪测量技术作为近年来发展的一种新兴地形测量技术,在废弃采石场地形测量中应用较为广泛。在介绍日本TopconCorporation公司生产的影像全站仪测量技术原理的基础上,以实例实现地形测量及后期成图的全过程。实践证明,影像全站仪测量技术具有操作简单、测量速度快、精度高等优点,特别是影像全站仪测量过程中不需要用棱镜进行光线反射,极大地提高了地形测量的效率,同时对测量人员的安全性也有保障,适用于常规测量难以实现的困难立地地形测量。