生态学杂志2012，Vol.31Issue(11)：2828-2833,6.
镉在泰来藻体内的累积规律及对光合作用的影响
Cadmium accumulation and its effects on the photosynthesis of Thalassia hemprichii
摘要
Abstract
By the methods of sequential extraction and chlorophyll fluorescence, a laboratory experiment with no sediments was conducted to study the cadmium (Cd ) accumulation in different organs of tropical seagrass Thalassia hemprichii and the effects of Cd on the photosynthesis of the seagrass. The Cd accumulation in T. hemprichii organs was in the order of leaf ＞ root ＞ rhizome. In all treatments, the Cd in the T. hemprichii organs was dominated by the 1 mol · L-1 NaCl-, 2% HAc-, and 0. 6 mol · L-1 HCl-extrac table Cd, occupying 80% -99% of the total Cd, indicating that the less active and weakly migrated forms were the main forms of Cd in T. hemprichii. Under the exposure of increasing concentration Cd, the proportion of 0. 6 mol · L-1 HCl-extractable Cd in different organs of T. hemprichii decreased by 1% -24% , while the proportion of 1 mol · L-1 NaCl- and 2% HAc-extractable Cd increased by 2% -24% . On the other hand, the 80% ethanol- and d-H2O-extractable Cd, the high active Cd forms, decreased in T. hemprichii leaf but increased in root and rhizome. These results suggested that T. hemprichii could weaken the toxicity of Cd by changing the proportion of different Cd forms in cells and/or organs. Under the exposure of high concentration Cd, the effective quantum yield (△F/Fm') and the chlorophyll a, chlorophyll b and total chlorophyll contents declined significantly, suggesting that the photosynthesis of T. hemprichii was seriously impaired. It seemed that the protective mechanisms evolved by T. hemprichu could play an important role in Cd detoxification when exposed to relatively low concentration Cd, but became restricted under higher Cd stress.关键词
镉/泰来藻/累积/化学形态/光合作用Key words
Cd/ Thalassia hemprichii/ accumulation/ chemical form/ photosynthesis分类
农业科技引用本文复制引用
冯韶辉,黄小平,江志坚..镉在泰来藻体内的累积规律及对光合作用的影响[J].生态学杂志,2012,31(11):2828-2833,6.基金项目
国家自然科学基金项目(41076069和40776086)和南海区海草床环境质量综合评价方法项目(DOMEP-(MEA)-01-03)资助. （41076069和40776086）
