Fisheries：练习题

What is a primary social and economic importance of marine organisms to human populations?

What is the primary function of sonar as a navigational aid in modern commercial fisheries?

Why is purse seine fishing generally considered to have a lower direct impact on the physical seafloor habitat compared to beam trawling?

Which fishing method involves the use of a single long horizontal main line with many shorter, baited branch lines attached at regular intervals?

Trawling is a fishing method that involves dragging a net along the seabed or through the water column. What is the major environmental impact associated with beam trawling?

Identify one type of netting used in commercial fisheries that is specifically designed to encircle a school of fish at the surface and then close at the bottom like a drawstring bag.

Explain how the use of sonar serves as a vital navigational and fishing aid for modern fishing vessels.

Evaluate the ecological impact of using Fish Aggregating Devices (FADs) in open-ocean fisheries.

Modern fisheries rely on various technologies and management techniques to harvest marine organisms effectively. Use your knowledge of fishing practices and sustainability to answer the following questions.

(a) State the primary purpose of a nautical chart as a navigational aid for a fishing boat. (1 mark)

(b) Identify one method of trapping fish or crustaceans that does not involve the use of a large net. (1 mark)

(c) Explain how the issuance of fishing licences helps authorities manage a local fishery. (1 mark)

Maintaining sustainable fisheries is essential for global food security and the health of marine ecosystems.

(a) Explain how sustainable harvesting ensures that fish stocks remain available for future generations. (2 marks)

(b) Describe the function of sonar and GPS as navigational aids in commercial fishing. (3 marks)