Quick-drop type vertical trawl used for biological resource investigation in Antarctic sea area and using method

Abstract

The invention relates to a quick-drop type vertical trawl used for biological resource investigation in an Antarctic sea area and a using method. The vertical trawl comprises a retractable rope, net opening edge ropes, support rods, a central support, a netting, a connecting platform and a collecting barrel, the lower end of the retractable rope is connected with the central support, and the central support is radially provided with a plurality of support rods in the circumferential direction; and the inner side ends of the support rods are rotatably connected with the central support, when the support rods rotate downwards to the horizontal position, the bottoms of the support rods and the central support form a limiting support in the horizontal direction, and the net opening edge ropesare elastic ropes and connected with the outer side ends of the support rods in the circumferential direction. The upper end of the netting is connected with the net opening edge ropes, the lower endof the netting is connected with the connecting platform, the netting is funnel-shaped when unfolded, and the upper end of the collecting barrel is connected with the connecting platform through a quick detachable structure. The vertical trawl can be folded, stored, transported and thrown, the descending speed of the trawl thrown into water can be increased, the overturning situation is effectively avoided, and sampling is convenient.

Description

technical field [0001] The invention belongs to the technical field of marine biological sampling nets, and in particular relates to a speed-drop vertical trawl used for the investigation of biological resources in the Antarctic sea area and a use method thereof. Background technique [0002] Marine plankton includes zooplankton and phytoplankton. The study of plankton is an important way to study marine biological resources, marine environment, fishery ecology, fish biology and other disciplines. The sampling of plankton depends on the sea area conditions, and the depth ranges from tens of meters to hundreds of meters. Especially in the investigation of biological resources such as Antarctic krill in the Antarctic waters, the depth of biological sampling can reach more than 200 meters, and usually dozens or even hundreds of sampling stations are required, and the workload is huge. [0003] At present, the commonly used plankton sampling technology is to use a funnel-shaped ...

AI Technical Summary

Problems solved by technology

Under this structure, if the size of the network port is too large, it is not suitable for carrying. At the same time, it will increase the difficulty of operation. The limited size of the network port will also affect the efficiency of biological collection.

When the vertical trawl net is lowered, the net mouth is generally parallel to the water surface, and it will be slightly inclined under the action of the water flow, and the descending resistance is relatively large, which affects the descending speed, thus prolonging the sampling time and increasing the workload

In addition, the lower part of the network port supported by the steel pipe circle is connected to the collection container. When the wind and waves are large or the flow rate is high, the collection container at the bottom will turn up and enter the network port, resulting in the inability to complete the sampling work.

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