摘要
采用连续浸提法测定了紫色土铜的形态,并用盆栽试验研究了铜对水稻的危害。结果表明,紫色土中原有铜以残留态为主,依次为碳酸盐态和弱专性吸附态、铁锰氧化物结合态和有机结合态,交换态的比例最小。铜在各形态间的分布因土壤不同而有较大差异。施铜导致残留态的比例下降,而使交换态、碳酸盐态和弱专性吸附态、铁锰氧化物结合态比例上升。铜对水稻影响的大小是酸性>中性>石灰性紫色土。初步认为,土壤铜的水溶-交换态、弱专性吸附态-碳酸盐态是对水稻有效的铜形态,土壤铜的毒性临界值以交换态和弱专性吸附态或碳酸盐态为指标,在30mg Cu/kg左右。
A study was conducted to fractionate Cu forms by a sequential extraction procedureand to examine the effect of added Cu on rice plant in acid,neutral and calcareous purplesoils.The data obtained revealed that the majority of native Cu in purple soil was found inthe residual form,the percentages of carbonates-bound or weakly specifically adsorbedlorm were secondary,Fe-Mn oxides bound and organically bound forms were zatherlow,and the proportion of water soluble plus exchangeable Cu was the smallest.The dis-tribution of various Cu forms differed with soil properties.The addition of Cu resulted in adrop in the percentage of residual Cu,and a rise in exchangeable,carbonates-bound orweakly specifically adsorbed Cu,and Fe-Mn oxides-bound Cu.The influence of Cu onrice plant decreased in the order of acid purple soil>neutral purple soil>calcareous pur-ple soil.The experiment results suggested that the fractions of soil Cu available to rice werethe water soluble plus exchangeable and carbonates or weakly specifically adsorbed forms.The critical toxic concentration of Cu represented by these fractions was about 30 mgCu / kg soil.
出处
《西南农业大学学报（自然科学版）》
CSCD
1992年第2期152-157,共6页
Journal of Southwest Agricultural University
关键词
铜
形态
毒性
紫色土
水稻
copper
morphology
toxicities
purple soils
paddy
