Plankton size spectra monitoring is crucial for managing and conserving aquatic ecosystems. Thus, we develop an in situ size spectra monitoring system to obtain the size spectra of plankton and the information of their living status underwater. The system consists of an imaging unit and an information processing unit. The imaging part applies a darkfield illumination to enhance the image contrast. Three lenses with different magnifications are alternated by a motor automatically to capture sizes of plankton from $3\,\mu$m to $3\,\text{mm}$. Moreover, the system can analyze the captured images in real time using the proposed multitask size spectra convolutional neural network, obtaining size spectra and density distribution of plankton simultaneously. Field test confirms that our system performs well both in imaging and information processing. Furthermore, the system can provide the living behavior of plankton, thereby helping biologists to study the aquatic ecosystem effectively and precisely.

中文翻译：

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通过卷积神经网络对浮游生物大小光谱进行基于视觉的原位监测

浮游生物大小光谱监测对于管理和保护水生生态系统至关重要。因此，我们开发了一个就地尺寸谱监测系统，获取浮游生物的尺寸谱及其水下生存状态信息。该系统由成像单元和信息处理单元组成。成像部分应用暗场照明来增强图像对比度。三个不同放大倍率的镜头由马达自动交替，以捕捉浮游生物的大小$3\,\mu$米到 $3\,\text{mm}$. 此外，该系统可以使用所提出的多任务尺寸谱卷积神经网络实时分析捕获的图像，同时获得浮游生物的尺寸谱和密度分布。现场测试证实我们的系统在成像和信息处理方面都表现良好。此外，该系统可以提供浮游生物的生活行为，从而帮助生物学家有效、准确地研究水生生态系统。