升温胁迫对珊瑚及其共生藻影响的初步研究

A preliminary study of effect of elevated temperature stress on three reef corals and their zooxanthellae

石珊瑚失去共生藻或光合色素就会发生白化。以石珊瑚体内、外正常与异常共生藻浓度及比例变化、珊瑚表面共生藻密度为参数,研究了3种珊瑚在3种温度(26℃、31℃、34℃)下的响应。结果表明,在未受(26℃)或受到较小(31℃)温度胁迫时石珊瑚体内、外共生藻浓度及比例保持稳定,正常共生藻占优势;受较强温度(34℃)胁迫时异常共生藻迅速占优势,游离出的共生藻增多,且3种石珊瑚都在该温度下48h内白化。石珊瑚及其共生藻处在相对稳定的共生体系中,受温度胁迫后大量共生藻游离出共生体系而发生白化至死亡。

Coral bleaches occurs once losing its symbiotic dinoflagellates or photosynthetic pigments. The responses of three corals from different families to three different levels of temperature （26℃, 31℃, 34℃） were studied taking the concentration and proportion changes of normal and abnormal zooxanthellae inside and outside the reef corals and the areal zooxanthellae population density as parameters. The results showed that the concentration and proportion of the zooxanthellae remained stable and the normal zooxan- thellae were dominant under no （26℃） or less （31℃） temperature stress; whereas the abnormal zooxan- thellae became dominant and dissociative zooxanthellae increased under severe （34℃） stress, and all of the three reef corals became bleached within 48h. The reef corals and their symbiotic dinoflagellates are both in a relative stable symbiont. When mass dinoflagellates dissociate under temperature stress, the corals will be bleached and die.