Use of spherical and spheroidal models to calculate zooplankton biovolume from particle equivalent spherical diameter as measured by an optical plankton counter
Use of spherical and spheroidal models to calculate zooplankton biovolume from particle equivalent spherical diameter as measured by an optical plankton counter
复制标题
使用球形和椭球体模型根据光学浮游生物计数器测量的颗粒当量球形直径计算浮游动物生物体积
DOI：
--
复制
发表时间：
2005
期刊：
影响因子：
--
通讯作者：
T. R. Anderson
中科院分区：
文献类型：
--
作者：
A. Mustard;T. R. Anderson
本文提出了三种利用光学浮游生物计数器（OPC）记录的粒子阴影计算粒子生物体积的方法。在第一种方法（Vsphere）中，假设粒子是不透明的球体。在其他两种方法中，颗粒被表示为不透明的球体，其主轴平行于流动从而呈现最大阴影面积（Vmax），或者相对于流动随机取向（Vran）。该模型进行了测试，通过比较净生物量，测量浮游动物组合占主导地位的哲水蚤finmarchicus在2001年期间，在东北大西洋巡航收集的样品。随机取向的球体模型（Vran）提供了与净数据的最佳拟合：平均而言，OPC生物体积与净生物体积的比值为1.02，相比之下，当计算OPC生物体积为Vmax时，比值为0.84，当计算为Vsphere时，比值为1.50。Vran和Vmax方法给出了OPC测量的净生物量的合理估计，而无需使用其他所需的经验调整参数。这一成功是由一个事实，即社区选择验证目的是由一个单一的物种，C。finmarchicus，这可以近似为已知尺寸的球体。校准方法是不太可能是有效的，当应用到浮游动物群落纳入各种各样的生物。
Three methods of calculating the biovolume of particles from their shadows as recorded by and optical plankton counter (OPC), based on optical geometry, are presented. In the first method (Vsphere), particles are assumed to be opaque spheres. In the other two methods, particles are represented as opaque spheroids, oriented with their major axes either parallel to the flow thus presenting maximum shadow area (Vmax), or randomly orientated relative to the flow (Vran). The models were tested by comparing with net biovolume, measured from samples of a zooplankton assemblage dominated by Calanus finmarchicus collected during a cruise to the northeast Atlantic during 2001. The randomly orientated spheroidal model (Vran) provided the best fit with the net data: on average the ratio of OPC biovolume to net biovolume was 1.02, compared to ratios of 0.84 when calculating OPC biovolume as Vmax and 1.50 when calculating as Vsphere. The Vran and Vmax methods gave reasonable estimates of net biovolume from OPC measurements without recourse to the use of empirical tuning parameters that are otherwise required. This success was enhanced by the fact that the community chosen for validation purposes was dominated by a single species, C. finmarchicus, which could be approximated by spheroids of known dimension. The calibration methods are less likely to be effective when applied to zooplankton communities incorporating a diverse range of organisms.