Multi-link quantitative sampling net for spawns and fish larvae

Abstract

The invention provides a multi-link quantitative sampling net for spawns and fish larvae. The multi-link quantitative sampling net comprises a rigid frame, a body net, a flexible settling sail, a plurality of bag nets and a bag net opening and closing control device; the outer edge of the opening part of the body net is fixed on a first surface of the rigid frame; the flexible settling sail comprises a sail body and sail boards, and sail boards are vertically fixed at both ends and the middle of the first surface of the sail body respectively and arranged in the width direction of the sail body. The cross section of the sail body in the width direction is in an arc shape which sinks toward the direction of a second surface of the sail body. The sail body bends toward the first surface of the sail body in the length direction; the sail body is detachably fixed to the bottom of the rigid frame through the sail boards; the bag net opening and closing control device sleeves and is fixed behind the body net, and the opening part of each bag net is connected in the bag net opening and closing control device. According to the multi-link quantitative sampling net for the spawns and fish larvae, the bag nets can be opened and closed automatically, and it can be ensured that the area of net mouths is constant during sampling operation, the towing water depth does not change with the speed of a ship, and the multi-link quantitative sampling net further has the advantages of convenient carrying, convenient storage and good stability.

Description

technical field [0001] The invention relates to the field of sampling nets, in particular to a multi-unit quantitative sampling net for fish eggs, larvae and juveniles. Background technique [0002] In order to truly strengthen the management of fishery resources and fully understand the marine ecosystem, it is necessary to quantitatively collect eggs and larvae of specific fish species to grasp their resources. At present, there is still a lack of a multi-layer quantitative sampling trawl net that can open and close autonomously and can be towed at high speed. [0003] At present, multi-layer sampling surveys of larvae and juveniles in foreign countries mainly use multi-layer sampling trawls such as MOCNESS, RMT and LOCHNESS. Among them, the MOCNESS sampling trawl can read a variety of information including the towing status on the ship in real time through the armored cable, but the network port has a large inclination, the towing speed cannot exceed about 2.0 knots, and ...

AI Technical Summary

Problems solved by technology

The opening frame of the LOCHNESS sampling trawl is a three-dimensional structure, and the area of ​​the opening is 5.0m 2 The frame weight is more than 1.0 tons, which is not suitable for small and medium-sized survey ships

Especially MOCNESS, LOCHNESS, RMT and other existing types of multi-layer sampling network opening and closing need to be controlled by armored cables, and must be equipped with corresponding twisting machine, the price is very expensive

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