不同土壤类型中水稻间作红蛋对镉累积的影响

Accumulation of Cd in Rice and Echinodorus osiris under Intercropping Conditions in Different Soil Types

开展根箱实验,比较水稻土和石灰岩土上镉(Cd)低累积常规水稻(玉丝占)间作红蛋(Echinodorus osiris)对Cd累积的影响。通过分析水稻和红蛋根区土壤pH、阳离子交换量(CEC)、有效硫(S)、有效钙(Ca)、有效镁(Mg)和不同形态Cd的变化,研究不同土壤类型中2种植物间作对Cd累积的影响。结果表明:与单种相比,间作可使水稻土上水稻地上部、地下部和籽粒中的Cd含量增加1.97%、3.91%和1.43%;使石灰岩土上水稻地上部、地下部和籽粒中的Cd含量降低11.17%、34.95%和15.38%。在水稻土上,间作对水稻根区土壤pH无显著影响,但增加了有效S、CEC和弱酸提取态Cd百分含量,分别增加84.05%、22.27%和16.13%。在石灰岩土上,间作使水稻根区土壤有效Mg含量显著增加,增加9.16%,使有效Ca含量降低5.25%,对pH、CEC和弱酸提取态Cd的百分含量影响不显著。

Rhizobox was carried out to investigate the effects of accumulation of Cd in plants under rice （Yusizhan） and Echinodorus osiris intercroppiug system in paddy soil and limestone soil. In addition, the changes of rice and Echinodor~ osiris root zone soil pH, cation exchange capacity （ CEC）, effective S, effective Ca, Mg and different forms of cadmium （Cd） content were analyzed to investigate the effects of accumulation of Cd in plants under intercropping conditions in different soil types. The results showed that in the paddy soil, compared with monocropping rice, intercropping of Echinodorus osiris increased the content of Cd in rice shoots, roots and grain by 1.97 %, 3.91% and 1.43 %, and in limestone soil, the intercropping condition made the Cd content in rice shoots, roots and grain reduced by 11.17 %, 34.95 % and 15.38 %. In paddy soil, intercropping of Echinodorus osiris had no significant effect on the pH of root zone soil of rice, but the effective S, CEC and percentage of acid extractable Cd increased by 84.05 %, 22.27 % and 16.13 % respectively. In the limestone soil, under intercropping condition, the effective Mg content of the soil in the root zone of rice increased by 9.16 %, but the effective Ca content decreased by 5.25 %, besides the pH, CEC and percentage of acid extractable Cd had no significant changes.