泰来草对海水中铜元素的耐受性及其不同器官吸收差异OACHSSCD

This study examined the tolerance of Thalassia hemprichii to copper(Cu²⁺)contamination in seawater and the differences in Cu2+absorption among its organs through controlled laboratory experiments with Cu² ⁺ gradients of 0～30 μg·L‒1.The accumulation characteristics of Cu2+in the aboveground(leaves),underground(rhizomes and roots),and de-trital tissues,along with physiological indicators including growth rate,photosynthetic products,and antioxidant activity,were systematically analyzed.The results showed that Cu2+content in the underground parts was significantly higher than that in the aboveground tissues(P<0.01),and detritus accumulated more Cu2+,which might facilitate its transfer to sedi-ments through degradation.Low Cu²⁺ concentrations(≤20 μg·L‒1)induced the accumulation of osmoregulatory substances and enhanced antioxidant enzyme(such as SOD)activity.In contrast,when Cu²⁺ concentrations exceeded 20 μg·L‒1,the primary production rate decreased by 16.9%～15.3%,and chlorophyll and SOD activities were significantly reduced(P<0.01).These findings indicate that T.hemprichii adapts to low-level copper pollution by regulating osmoregulatory sub-stances and boosting antioxidant activity,while higher concentrations of Cu²⁺ significantly inhibit its growth and physiologi-cal activity.The study further reveals that T.hemprichii immobilizes Cu2+through an"absorption-burial"mechanism,transferring Cu2+to sediments,effectively reducing the concentration of Cu2+in seawater.The current research provides a theoretical basis for the remediation of heavy metal pollution in seagrass bed ecosystems and offers a reference for the fu-ture control of marine heavy metal pollution.