悬浮物对造礁石珊瑚营养方式的影响及其适应性研究进展

Abstract

营养方式是造礁石珊瑚获取能量与营养物质的基础，影响其生长与分布。近年来珊瑚礁区悬浮物含量与组分结构发生显著变化，其对造礁石珊瑚营养方式的诸多影响正成为当前研究热点。研究系统综述了珊瑚礁区悬浮物变化特征、悬浮物对造礁石珊瑚营养方式的影响及其适应性研究现状。发现近年来人类活动加剧与强降雨事件频发是驱动珊瑚礁，尤其是近岸珊瑚礁区悬浮物含量递增、组分改变与变频加剧的主因；悬浮物变化对造礁石珊瑚光合自养与异养营养的影响存在显著的种间差异，这主要与悬浮物消光效应、生物可利用性及造礁石珊瑚种类密切相关。虽然少数种类造礁石珊瑚具光合可塑性或异养可塑性，能在高含量悬浮物存在的弱光环境中较好生长。然而对绝大多数造礁石珊瑚而言，其营养方式适应性较差，无法在悬浮物影响下较好地获取生命活动所需的能量与营养物质，进而难以生存。总体来说，悬浮物被认为是近年来影响造礁石珊瑚生长与分布的重要环境因子之一，而关于造礁石珊瑚营养方式对悬浮物变化的响应及其适应机制，当前研究仍较薄弱，需要进一步加强相关研究。;The nutritional mode is the basis for scleractinian corals to obtain energy and nutrients, which affects their growth and distribution. In recent years, the content and composition of suspended sediment in coral reefs have changed significantly, and many effects on the nutritional mode of scleractinian corals are becoming the focus of current research. This article reviewed the characteristics of the suspended sediment changes in coral reefs, the effects of suspended sediment on the nutritional mode of scleractinian corals and their adaptability. The results show that the intensification of human activities and the frequent occurrence of heavy rainfall events in recent years are the main reasons driving the increase in suspended sediment concentration, composition changes and frequency conversion in coral reefs, especially in fringing reefs. The influences of suspended sediment on autotrophy and heterotrophy of scleractinian corals are significantly different, which are mainly related to the extinction effect and bioavailability of suspended sediment, and the species of scleractinian corals. Although some species of scleractinian corals have photosynthetic plasticity or heterotrophic plasticity, they can grow well in low-light environments where high levels of suspended sediment exist. However, for the majority of scleractinian corals, the adaptability of nutritional mode is poor, so they can't obtain the energy and nutrients needed for living better under the influence of suspended sediment, which makes them difficult to survive. Overall, suspended sediment is considered to be one of the important environmental factors affecting the growth and distribution of scleractinian corals in recent years. However, the present studies on the response and adaptability mechanism of the nutritional mode of scleractinian corals to the change of suspended sediment are still rare, and further research is needed.