摘要
本文研究了酸性、中性及石灰性紫色土中铅的水稻效应、形态特征及有效性。酸性与石灰性紫色土中水稻分别在含铅量1000、2000mg/kg时出现明显受害,中性紫色土在4000mg/kg时亦无明显影响。水稻各部位含铅量是酸性>石灰性>中性紫色土,并与添加铅呈显著正相关,且其大小顺序为根>茎叶>糙米。铅90％以上积累于水稻根部;施铅使土壤中无效铅比例下降。有效性较高的铅形态比例上升。交换态、碳酸盐态或弱结合态铅含量较高的土壤上,水稻反应大。用有效态铅为指标有可能使不同土壤铅临界浓度比较接近一致。
The form and availability of Pb and its ef- feet on rice in acideaeutral anti calcareous purple soils were studied. Significant injury was found in rice growing in acid and calcareous purple soils at 1000 and 2000 rng/kg Pb,respectively. However,no significant injury was found in neutral purple soil at Ph up to 4000mg/kg. Ph content in different parts of plant ricf was significantly related to Ph added in soil and in orders of acid purple soil>calcareous purple soil >neutral purple soil ,and roots >rice straw > brown rice. Pb was mostly remained in roots, accounting for more than 90% of Pb absorbed by rice. The addition of Pb increased the proportion of more available Pb fractions. and reduced that of residual fraction. Plant responses to Pb were more sensitive in soil with higher exchangeable and / or carbonate or weakly bound Pb. Available Pb may unify the critical concentration of Pb in various soils.
出处
《农村生态环境》
CSCD
1993年第2期54-57,共4页
Rural Eco-Environment
