超积累生态型东南景天吸收锌的特性  

The characteristic of Zn uptake by the hyperaccumulating ecotype of Sedum alfredii Hance

作　　者：龙新宪[1] 倪吾钟[2] 叶正钱[2] 杨肖娥[2] 

机构地区：[1]华南农业大学资源与环境学院环境科学与工程系,510642 [2]浙江大学环境资源学院环境修复生态健康教育部重点实验室,杭州310029

出　　处：《生态学报》2006年第2期334-340,共7页Acta Ecologica Sinica

基　　金：国家杰出青年科学基金资助项目(39925024);国家自然科学基金资助项目(20407008);华南农业大学博士启动基金资助项目~~

摘　　要：采用水培和盆栽方法研究超积累生态型东南景天吸收锌的特征。在水培条件下,1μmol·L-1Zn处理,根系Zn含量随着处理时间的增加而缓慢增加,叶片和茎Zn含量在处理2d后达到最大值,随着培养时间的延长,其含量略有下降。500μmol·L-1Zn处理水平下,叶片和茎Zn含量随着处理时间的增加而增加,处理16d后基本上达到稳定,根系Zn含量在0～16d增加缓慢,但处理16d后急剧上升。当溶液Zn浓度为1～500μmol·L-1,叶片和茎Zn含量随营养液中Zn浓度的增加而增加,而根系Zn含量增加缓慢;当溶液Zn≥1000μmol·L-1时,叶片和茎Zn含量急剧下降,而根系Zn含量迅速增加。盆栽条件下,当土壤Zn含量较低时时,土壤Zn促进东南景天的生长。5月13日和7月21日收获的植株地上部的干物质量分别在400mg·kg-1(0.71g盆-1)和800mg·kg-1(1.45g盆-1)处理达到最大值。但当土壤Zn添加量≥1600mg·kg-1时,植物的生长受到抑制。随着土壤中Zn添加量的增加,东南景天地上部Zn浓度变化趋势基本上与其生物量的变化一致。5月13日收获时,当土壤Zn添加量≤1600mg·kg-1,地上部Zn含量随着土壤Zn浓度的增加而增加,在1600mg·kg-1处理达到最大值,约为17000mg·kg-1(DW)。7月21日收获的结果显示,当土壤Zn添加量≤800mg·kg-1,地上部Zn含量随着土壤Zn浓度的增加而增加,最大值为29000mg·kg-1(DW);但当土壤Zn添加量≥1200mg·kg-1时,地上部Zn含量反而随着土壤Zn含量的增加而显著降低。Solution culture and pot experiments were conducted to study the characteristic of Zn uptake in Sedum alfredii Hance. At Zn level of 1μmol·kg^-1 in nutrient solution, Zn concentrations in leaves and stems increased slightly with treatment time and reached maximum at day 2 of the treatment, then slightly decreased, where as minimal changes in root Zn concentrations were noted. At Zn level of 500 μmol·kg^-1, Zn concentrations in leaves and stems increased sharply with time, and peaked at day 16 d, where as root Zn concentrations increased slowly with the time up to 16 d, and then sharply increased. The concentrationdependent of Zn uptake showed a fast increase component at Zn levels from 1 to 500μmol·kg^-1 , followed by a sharp decrease in leaf and stem Zn concentration when grown at Zn levels ≥1000μmol·kg^-1. In contrast, Zn concentration in the roots increased slightly when Zn supply level was increased from 1 to 500μmol·kg^-1, and raising solution Zn above 1000μmol·kg^-1 rapidly increased Zn concentration in roots. Our results from pot experiment showed that shoot Zn concentration increased with Zn levels in the soil, and reached the maximum of approximately 17000 mg·kg^- 1 （DW） harvested on May 13 at soil Zn levels of 1600 mg· kg^- 1, and around 29000 mg·kg^- 1 harvested on July 21 at soil Zn levels of 800 mg·kg^- 1 , However, higher Zn concentration （added Zn≥1200 mg· kg^-1） in soil resulted in decrease of Zn concentration in the shoots.

关 键 词：东南景天 锌 

分 类 号：X173[环境科学与工程—环境科学]