食物相暴露条件下尼罗罗非鱼对砷的累积与转化  

Accumulation and transformation of arsenic in Oreochromis niloticus under food phase exposure

作　　者：宋梦萍 杨常亮[2] 张璟 黄中情 曾绍宇 刘雯清 何发涛 SONG Mengping;YANG Changliang;ZHANG Jing;HUANG Zhongqing;ZENG Shaoyu;LIU Wenqing;HE Fatao(Institute of International rivers and eco-security,Yunnan University,Kunming,650091,China;School of Ecology and Environment Science,Yunnan University,Kunming,,650091,China)

机构地区：[1]云南大学国际河流与生态安全研究院,昆明650091 [2]云南大学生态与环境学院,昆明650091

出　　处：《环境化学》2022年第6期1897-1904,共8页Environmental Chemistry

基　　金：国家自然科学基金(51168047)资助.

摘　　要：为研究不同类型、不同营养级的生物对砷(As)的累积与转化作用,采用室内培养试验,选取杂食性淡水鱼类尼罗罗非鱼(Oreochromis niloticus)为研究对象,让其分别摄食暴露于1 mg·L^(−1)砷酸[As(Ⅴ)]水溶液中15 d的浮水植物青萍(Lemna minor L.)、沉水植物轮叶黑藻(Hydrilla verticillate)、节肢动物日本沼虾(Macrobrachium nipponense),研究不同食物相暴露条件下尼罗罗非鱼对砷的累积与转化作用.结果发现,动植物能吸收并累积水中的砷,且随着暴露时间的增加,其对含砷水环境有一定的适应性;尼罗罗非鱼摄食不同类型的食物之后,其肌肉组织中累积的砷含量不同,但总砷量与食物相中的浓度趋势一致,为投喂青萍组>投喂轮叶黑藻组>投喂日本沼虾组;当罗非鱼通过食物摄入砷,相较于一甲基砷酸(MMA)和二甲基砷酸(DMA),As(Ⅴ)更容易转化为亚砷酸[As(Ⅲ)],砷被蓄积与转化后主要以砷甜菜碱(AsB)的稳态形式存在;不同生物对砷的累积和转化方式不同,水生动物更易将无机砷甲基化为毒性较小的AsB;投喂日本沼虾的罗非鱼对砷的生物转化能力最高,砷在营养转移过程中可沿食物链传递但没有在罗非鱼中生物放大.In order to study the accumulation and transformation of arsenic(As)by different types and different trophic levels of organisms,an indoor culture experiment was carried out.The omnivorous freshwater fish Oreochromis niloticus was selected as the research object,and they were exposed to the floating plant Lemna minor L.,submerged plant Hydrilla verticillate and arthropod Macrobrachium nipponense which exposed to 1 mg·L^(−1) arsenate[As(Ⅴ)]aqueous solution for 15 days to study the accumulation and transformation of arsenic in Oreochromis niloticus under different food exposure conditions.The results show that animals and plants can absorb and accumulate arsenic in ponding,and they have a certain adaptability to arsenic containing water environment with the increase of exposure time;After feeding different types of food,the arsenic content accumulated in muscle tissue of Oreochromis niloticus was different,but the total arsenic content was consistent with the concentration trend in food phase,which was feeding Lemna minor L.group>feeding Hydrilla verticillate group>feeding Macrobrachium nipponense group;When Oreochromis niloticus ingests arsenic through food,compared with monomethyl arsenic(MMA)and dimethyl arsenic(DMA),As(Ⅴ)was easier to convert to arsenite[As(Ⅲ)].After arsenic was accumulated and transformed,it mainly existed in the steady-state form of arsenic betaine(AsB)in fish;Different organisms had different ways of arsenic accumulation and transformation.Aquatic animals were more likely to methylate inorganic arsenic into less toxic AsB;Oreochromis niloticus fed with Macrobrachium nipponense had the highest biotransformation ability of arsenic,and arsenic can be transferred along the food chain during nutrient transfer,but it was not biomagnified in fish.

关 键 词：尼罗罗非鱼 砷 食物链 营养转移 生物累积 生物转化 

分 类 号：X171.5[环境科学与工程—环境科学]