华南甘蔗种植区大气氮素湿沉降特征  

Atmospheric Wet Deposition of Nitrogen to Sugarcane Planting Region in South of China

作　　者：黄金生[1] 周柳强[1] 曾艳[1] 谢如林[1] 区惠平[1] 朱晓晖[1] 谭宏伟[1] HUANG Jin-sheng;ZHOU Liu-qiang;ZENG Yan;XIE Ru-lin;OU Hui-ping;ZHU Xiao-hui;TAN Hong-wei(Agricultural Resources and Environmental Research Institute/Southem Scientific Observation Station of Plant Nutrition and Fertilization Technology of Ministry of Agriculture,Guangxi Nanning 530007,China;Guangxi Academy of Agricultural Sciences,Guangxi Nanning 530007,China)

机构地区：[1]广西农业科学院农业资源与环境研究所/农业部华南植物营养与施肥技术科学观测实验站

出　　处：《西南农业学报》2019年第11期2615-2622,共8页Southwest China Journal of Agricultural Sciences

基　　金：广西农业科学院科技发展基金项目(桂农科2015JZ06;2015YT30;2015YT38);农业部科技专项项目(201003014)

摘　　要：【目的】对华南甘蔗种植区大气氮素湿沉降量进行估算,以期为区域氮素沉降及其生态环境效应评估提供数据支撑。【方法】在广西南宁市赤红壤甘蔗种植区,采用雨量计连续8年(2008年1月至2015年12月)采集降雨水样,测定其硝态氮、铵态氮和全氮含量,研究该地区大气湿沉降浓度及沉降量的月、季和年度变化。【结果】雨水中NO3^--N、NH4^+-N、DIN和TN浓度各月的差异较大,分别为0.08~3.80、0.04~3.25、0.12~5.52和0.20~6.65 mg N L^-1,月均浓度分别为0.73、0.67、1.40和1.89 mg N L^-1,呈春季>冬季>夏季>秋季;NO3^--N、NH4^+-N、DIN和TN沉降年平均浓度分别为0.53、0.51、1.04和1.45 mg N L^-1。雨水中NO3^--N、NH4^+-N、DIN和TN浓度与降雨量呈极显著负相关,沉降量与月降雨量、月降雨频次呈显著正相关,且受降雨量的影响大于降雨频次的影响;不同形态氮沉降量呈夏季>秋季>春季>冬季。NO3^--N、NH4^+-N、DIN和TN年均沉降量分别为6.55、6.32、12.86和17.95 kg N hm^-2,TN远超过陆地生态系统的临界负荷。DIN是大气氮素湿沉降的主体,占氮素总沉降的72.50%,DIN中NO3^--N和NH4^+-N分别为TN比例的36.87%和35.63%,两者的沉降量比例无明显差异。NH4^+-N沉降量占TN沉降量比例呈逐年下降趋势,NO3^--N沉降量占TN沉降量比例有逐年升高的趋势。【结论】华南甘蔗种植区大气氮素湿沉降量与氮沉降浓度呈现明显季节性差异,两者间呈相反趋势;雨水中各形态氮浓度与降雨量呈极显著负相关;月氮沉降量与月降雨量、月降雨频次呈显著正相关;无机氮是大气氮素湿沉降的主体,铵态氮和硝态氮沉降量占全氮沉降量比例分别呈逐年下降和升高的趋势。该区域大气氮素湿沉降高,年均沉降17.95 kg N hm^-2,超过陆地生态系统的临界负荷,对生态环境有一定潜在的风险。【Objective】The study aimed to estimate the atmospheric wet deposition of nitrogen to sugarcane planting region in south of China in order to provide data support for regional nitrogen deposition and its ecological environment effect assessment.【Method】Rainwater samples were collected in Nanning city,Guangxi Province during 2008 to December 2015 period.The concentrations of nitrate(NO-3-N),ammonium nitrogen(NH+4-N),inorganic nitrogen(DIN)and total nitrogen(TN)were analyzed.Based on these data,the monthly,seasonal and annual variations of atmospheric wet deposition concentrations were studied.【Result】The results showed monthly mass concentration for NO3^--N,NH4^+-N,DIN and TN in rainwater.The extent concentration of NO3^--N,NH4^+-N,DIN and TN were 0.08 to 3.80,0.04 to 3.25,0.12 to 5.52 and 0.20 to 6.65 mg N L^-1 respectively.The monthly average concentration of NO3^--N,NH4^+-N,DIN and TN were 0.73,0.67,1.40 and 1.89 mg N L^-1 respectively.The concentration of NO3^--N,NH4^+-N,DIN and TN were higher in spring and winter than in summer and autumn.The annual average concentration of NO3^--N,NH4^+-N,DIN and TN were 0.73,0.67,1.40 and 1.89 mg N L^-1 respectively.The concentration of NO3^--N,NH4^+-N,DIN,TN and rainfall were extremely significant negative correlation relationship.The deposition of NO3^--N,NH4^+-N,DIN,TN and rainfall,rainfall frequency were significantly positive correlation relationship.The deposition of NO3^--N,NH4^+-N,DIN and TN were higher in summer and autumn than in spring and winter.The annual average deposition of NO3^--N,NH4^+-N,DIN and TN were 6.55,6.32,12.86 and 17.95 kg N hm^-2 respectively.And the deposition of TN was higher than critical load of field ecosystem,mainly in form of DIN that accounted for 72.5%of the TN.NO3^--N and NH4^+-N accounted for 36.87% and 35.63% of the DIN.The percentage of NH4^+-N in TN was decreased year by year and inverse in NO3^--N.【Conclusion】The present results indicate that the deposition and concentration of different N forms in rainwater in South

关 键 词：大气湿沉降 氮沉降 华南 甘蔗种植区 

分 类 号：S566.1[农业科学—作物学]