^(36)Cl—氯化铵在模拟陆地—水域生态系统中的迁移和分配

MOVEMENT AND DISTRIBUTION OF ^(36)Cl—AMMONIUM CHLORIDE IN MODEL TERRESTRIAL AND AQUATIC ECOSYSTEMS

本研究应用模拟生态系统和同位素示踪技术进行.施于土壤的^(36)Cl-NH_4Cl,在为期21天的追踪试验,水稻吸收^(36)Cl 占施用量的26.02%;随土壤渗漏水淋脱51.61%;残留于土壤约为27.02%;集中土壤渗漏水放养芜萍、草鱼和螺,10天的吸收试验,均能吸收水中的^(36)Cl,并在体内有一定的积聚,其积聚比为:芜萍5.8;鱼内脏(9.9)>鳃(7.1)>骨(5.7)>肉(5.1);螺肉1.1;吸收有^(36)Cl 的鱼、螺转入洁水环境后5天,体内的^(36)Cl 因排泄而能较快消失,其消失率鱼肉达76.72%,螺肉为77.58%.因此,水田施用氯化铵不致于引起土壤中氯的积累而导致氯害.

Movement and distribution of ^(36)Cl ion were investigated in the model ecosystem includingsoil-rice-water-aquatic organisms by using radioisotope tracer techniques.~36c1-ammonium chloride(1.28MBq)was applied into soil.The recoveries from different phases were determined in 3 weeks.About26.02% of the applied dose was uptaken by rice root,among which 94.69% moved up to stalk.Of the ap-plied dose,51.61% was leached and 27.02% remained in soil.^(36)Cl was absorbed and accumulated inWolffia arrhiza Wimm, grass carp(Ctenopharyngodon idellus)and spiral shell after they were introduced intothe leakage for 10 days.The accumulation ratios in Wolffia arrhiza Wimm and flesh of spiral shell were 5.8and 1.1 respectively,and those in viscera,gills,bones and flesh of fish were 9.9,7.1,5.7 and 5.1respectively.After the contaminated fish and spiral shell were transferred into clean water,^(36)Cl in their bod-ies decreased quickly for excretion.In 5 days,the decrease ratio from flesh of spiral shell was 77.58%,andthose from bones,flesh,gills and viscera offish were 89.61,76.72,68.89 and 68.72% respectively.