Amphipods fail to suppress the accumulation of Ulva lactuca biomass in eutrophic Yundang Lagoon
The Gross growth efficiency (GGE) is defined as the amount of consumer carbon produced relative to the amount of prey ingested in a given time interval.In population ecology,it can be considered as an index for the ability of a consumer to convert the biomass of food into its population production.In this study,it was firstly applied to estimate the role of amphipods grazing in the biomass dynamics of macroalgae (Ulva lactuca) in Yundang Lagoon (a subtropical eutrophic coastal lagoon,Xiamen City,China).It was found that amphipods were the dominant group (82.2%~98.7%) in the benthic assemblage,in which five amphipod species (Corophium uenoi,Ampithoe valida,Grandidierella japonica,Grammaropsis laevipalmata and Caprella panantis) were observed in the lagoon.However,only A.valida significantly consumed U.lactuca among these amphipod species.A series of experiments were conducted to estimate the consumption of U.lactuca by A.valida.It was suggested that the monthly secondary production (P) of A.valida using size frequency method ranged from 2.39 to 13.68 g DW/m2.GGE of A.valida exponentially reduced with body size and was closely associated with water temperature.Therefore,GGE equation for different months using the temperature recorded during the field investigation was fitted.The monthly consumption of U.lactuca was figured out to be 86.7-1549.0 g DW/m2 by the sum of consumption (P/GGE) by A.valida at different size,accounting for 2.0-37.5%of U.lactuca production.It indicates that the grazing effect of A.valida did play a role in reducing the accumulation of U.lactuca biomass when A.valida was abundant,but it finally fails to limit the U.lactuca growth in Yundang Lagoon.Low abundance of A.valida and high nutrient loading may be two major reasons for the outbreak of U.lactuca bloom in the lagoon.
amphipods Ampithoe valida consumption gross growth efficiency secondary production Ulva lactuca
ZHENG Xinqing HUANG Lingfeng WANG Qian LIN Rongcheng
Third Institute of Oceanography,State Oceanic Administration,Xiamen 361005,China Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems,Xiamen University,Xia China Ocean Press,Beijing 100081,China
国内会议
福建省海洋学会2014年学术年会暨福建省科协第十四届学术年会分会场
福建平潭
英文
21-36
2014-09-01（万方平台首次上网日期，不代表论文的发表时间）