苏北海岸带盐沼外源苯的环境归趋:自然移除  

Environmental Fate of Exogenous Benzene Gas in Salt Marshes in Coastal Zone of the North of Jiangsu Province:Nature Removal

作　　者：王进欣[1] 黄巧华[1] 李超[1] 郭楠[1] 张威[1] 王今殊[1] 

机构地区：[1]江苏师范大学城市与环境学院,江苏徐州221116

出　　处：《湿地科学》2014年第6期784-790,共7页Wetland Science

基　　金：国家自然科学基金项目(31100361和41271122)资助

摘　　要：挥发性苯在环境中的长期暴露具有致癌和致其他疾病的风险,严重威胁着人的身体健康。分别于植物生长季(2004年7月)和非生长季(2005年1月),在苏北海岸带盐沼,采用静态箱技术,沿环境梯度原位测定苯通量。结果表明,研究区大气中挥发性苯的浓度明显高于国家规定的最大允许浓度,在海—陆变化梯度上,大气挥发性苯浓度变化呈现V字形空间变化趋势;研究区大气中挥发性苯可能源于沿海工业和汽车排放以及外海海水溶解挥发性苯的横向输送。盐沼生态系统对大气中外源挥发性苯的自然移除特征主要表现在:1海岸带盐沼植物和土壤是大气中挥发性苯的重要汇,而且对其上生长的植物具有显著的物种依赖性;植物对外源输入的挥发性苯的自然吸收通量可能与其生物量、叶面蜡质含量和气孔丰度有关,而土壤的自然移除能力可能取决于土壤温度、孔隙度、有机质含量、全氮含量以及可溶性盐总量;2海岸带盐沼对于外源输入的挥发性苯的自然吸收通量具有显著的季节和空间变化,这种变化源于植物及其根际环境对挥发性苯的自然吸收能力和对生态因子响应敏感性程度的差异性;3互花米草(Spartina alterniflora)的入侵并没有增加海岸带盐沼对挥发性苯气体的自然吸收通量。Volatile benzene exposure in the environment can lead to risk of cancer and other diseases,and has a serious threat to human health.The fluxes of benzene were measured seasonally using static flux chambers along an elevation gradient in salt marshes in coastal zone of the north of Jiangsu province,China.Main results were as follows,atmospheric concentration of volatile benzene was significantly higher than the maximum allowable concentration prescribed by the state,along gradient from sea to land in study area,trend of variation of benzene was V-shaped curve,inferred that volatile benzene of the atmosphere might be from external input of seawater,coastal industrial and vehicle emissions.The characteristics of natural removal of exogenous volatile benzene in coastal salt marshes mainly showed that the plants and soils in coastal salt marshes were important sink of volatile benzene,natural removal flux of soil was more than that of plant,and its strength had significant species dependent.Ability to natural removal of the volatile benzene of higher plants might be related to biomass,foliar wax content and stomata abundance.The ability natural removal of the volatile benzene of the soil might depend on soil temperature,porosity,organic matter content,nitrogen content,and total soluble salts.Seasonal and spatial variation of natural removal flux of volatile benzene were significant,it was from the seasonal and spatial difference of natural removal capacity from higher plants,their rhizosphere micro-environment,and the sensitivity degree of response to ecological factors.Spartina alterniflora invasion did not increase removal capacity of benzene of coastal salt marshes.

关 键 词：外源挥发性苯 自然移除 盐沼 吸收通量 环境归趋 互花米草 

分 类 号：X142[环境科学与工程—环境科学] Q178.531[生物学—水生生物学]