Metabolism of mesopelagic and bathypelagic copepods in the western North Pacific Ocean
Metabolism of mesopelagic and bathypelagic copepods in the western North Pacific Ocean
复制标题
北太平洋西部中上层和深海桡足类的代谢
DOI：
10.3354/meps322199
复制
发表时间：
2006
影响因子：
2.5
通讯作者：
T. Matsuishi
中科院分区：
文献类型：
--
作者：
T. Ikeda;F. Sano;A. Yamaguchi;T. Matsuishi
研究人员对来自亚北极太平洋西部中上层（M； 500至1000米）、上层深海（UB； 1000至2000米）和下层深海（LB； 2000至3000米）的50多种桡足类动物进行了呼吸（=耗氧）速率和电子传递系统（ETS）酶活性与身体碳和氮组成（用于呼吸）或蛋白质（用于ETS）的测定。在原位温度（M区、UB区和LB区分别为3、2和1.5°C）下，M区桡足类（平均：1.1%体碳d -1）的计算比呼吸速率（SR，体碳呼吸的一部分）大于UB区和LB区桡足类（均为0.6%体Cd -1）。用Q10值（2.0）调整到1°C时的呼吸速率，用体重指数（0.8）调整到1 mg体氮时的呼吸速率（例如，在μ l O2 （mg体氮）-0.8 h -1中调整的代谢速率，AMR）， M区桡足类的呼吸速率也大于UB和LB区桡足类。ETS活性以µl O2 （mg蛋白）-0.8 h -1表示，从M区到LB区显示出相同的深度相关下降。逐步回归分析显示，阶段/性别、摄食类型和/或反应速度（根据髓鞘包裹轴突的存在/缺失来判断）可能是影响桡足类呼吸速率和ETS活动的附加变量。当加入北极/南极上层桡足动物的呼吸速率数据时，从M区到UB或LB区呼吸速率和ETS活动的降低更为明显；当从亚北极太平洋占主导地位的桡足类中加入呼吸速率数据时，ETS活动也是如此。本研究结果与其他地区在500 - 2000米范围内收集的微孔甲壳类和鱼类标本进行了比较，并根据“视觉相互作用”假说进行了讨论。
Respiration (= oxygen consumption) rates and electron transport system (ETS) enzyme activities in conjunction with body carbon and nitrogen composition (for respiration) or protein (for ETS) were determined for over 50 copepod species from the mesopelagic (M; 500 to 1000 m), upper- bathypelagic (UB; 1000 to 2000 m) and lower-bathypelagic (LB; 2000 to 3000 m) zones of the western subarctic Pacific. Calculated specific respiration rates (SR, a fraction of body carbon respired) at in situ temperatures (3, 2 and 1.5°C for the M, UB and LB zones, respectively) were greater for the M zone copepods (mean: 1.1% body C d -1 ) than that for the UB and LB zone copepods (both 0.6% body Cd -1 ). Respiration rates adjusted to those at 1°C by using a Q10 value (2.0), and to those of specimens with 1 mg body nitrogen by using a body mass exponent (0.8) (e.g. adjusted metabolic rates, AMR, in µl O2 (mg body N) -0.8 h -1 ) were also greater for the M zone copepods than for the UB and LB zone copepods. ETS activities, measured as µl O2 (mg protein) -0.8 h -1 , showed the same depth-related decline from the M zone to the LB zone. Stepwise regression analysis revealed that stage/sex, feed- ing type and/or reaction speeds (as judged by the presence/absence of myelin sheath enveloping axons) of copepods were possible additional variables affecting their respiration rates and ETS activ- ities. The reduction in respiration rates and ETS activities from the M zone to the UB or LB zone is more pronounced when respiration rate data on Arctic/Antarctic epipelagic copepods is added; the same is true for ETS activities when respiration rate data is added from copepods dominant in the subarctic Pacific. The present results are compared with those of micronektonic crustaceans and fishes reported for specimens collected from 500 to 2000 m in other regions and discussed in the light of the 'visual interactions' hypothesis.