MOCNESS

MOCNESS

The MOCNESS (Multiple Opening/Closing Net and Environmental Sensing System) is an advanced oceanographic instrument used for sampling plankton and other small marine organisms at various depths in the ocean. It is a sophisticated tool that allows researchers to collect biological samples while simultaneously recording environmental data such as temperature, salinity, and depth.

Design and Functionality

The MOCNESS system consists of a series of nets that can be opened and closed sequentially at different depths. This allows for discrete sampling of the water column, enabling scientists to study the vertical distribution of marine organisms. Each net is equipped with sensors that provide real-time data on environmental conditions, which is crucial for understanding the habitat and behavior of the sampled organisms.

Components

• Frame: The MOCNESS is mounted on a sturdy frame that supports the nets and sensors. The frame is designed to withstand the pressures of deep-sea environments.
• Nets: Typically, the system includes multiple nets (usually 5 to 20) that can be opened and closed independently. The nets are made of fine mesh to capture small organisms.
• Sensors: The system is equipped with various sensors, including CTD (Conductivity, Temperature, Depth) sensors, fluorometers, and oxygen sensors, to collect environmental data.
• Control System: The opening and closing of the nets are controlled remotely from the research vessel, allowing precise sampling at desired depths.

Applications

MOCNESS is widely used in marine biology and oceanography for:

• Studying Plankton Distribution: By sampling at different depths, researchers can analyze the vertical distribution of plankton and understand their role in the marine food web.
• Environmental Monitoring: The system provides valuable data on oceanographic conditions, which is essential for monitoring changes in marine ecosystems.
• Biodiversity Assessments: MOCNESS helps in assessing the biodiversity of marine organisms in different oceanic regions.

Advantages

• High Resolution: The ability to sample at multiple depths provides high-resolution data on the vertical distribution of marine life.
• Simultaneous Data Collection: Environmental data is collected simultaneously with biological samples, providing a comprehensive view of the ecosystem.
• Versatility: MOCNESS can be used in various marine environments, from coastal areas to the open ocean.

Limitations

• Complexity: The system is complex and requires skilled personnel to operate and maintain.
• Cost: MOCNESS is an expensive piece of equipment, which may limit its use to well-funded research projects.

History

The development of MOCNESS was driven by the need for more precise sampling methods in oceanography. It was first introduced in the 1970s and has since become a standard tool in marine research.

Also see

• Plankton
• Oceanography
• Marine Biology
• CTD (instrument)