Marine biological resources have their own characteristics: they are alive, self-propagating and constantly updating, but on the other hand, because they are developed through the reproduction of living animals and plants, the resources are updated and supplemented, and they have certain spontaneous adjustment ability, which is a dynamic balance process. But once its ecosystem balance is destroyed, it means the destruction of marine living resources.
Algae occupies a special and important position in marine biological resources. It can carry out photosynthesis on its own, produce a lot of organic matter and provide enough food for marine animals. At the same time, it also releases a large amount of oxygen in photosynthesis, with a total output of 36 billion tons (accounting for 70% of the oxygen content in the earth's atmosphere), providing necessary oxygen for marine animals and even land creatures.
Here, it must be mentioned that it is the "hero" of the initial transformation of the earth's atmosphere to the modern atmosphere. With them, a modern and dynamic biological world has emerged. Therefore, marine plants are the basis of maintaining the whole marine life and a solid "pyramid base". They mainly include phytoplankton floating in the water and large algae growing on the seabed. The former, such as diatoms and green algae, are tiny and have different shapes, such as round, square, triangle and needle. If you only look at them from the outside, you will never think they are living plants.
Macroalgae include the familiar laver and kelp. They form a "submarine farm" on the seabed, with forests and grasslands. There is a giant seaweed, which is the most abundant plant in the world, ranging from tens of meters to hundreds of meters, up to 500 meters, and weighing 180 kilograms. It grows very fast, growing more than 50 meters a year and reaching the age of 12 years. Seaweed is of great value in industry, agriculture, food and medicine. Besides edible, fucoidan, agar, mannitol and iodine can be extracted from it, which can be used as a new bioenergy.
The most important and vivid marine life is animal resources, including fish1.5-40,000 species, crustaceans such as prawns over 20,000 species, molluscs such as shells over 80,000 species, whales, sea cucumbers, seals, walruses, seabirds, etc., which constitute a vibrant marine world and marine aquaculture with good economic benefits, among which fish is the main body of aquatic products and the most important.
At present, 90% of the 60 million tons of aquatic products caught from the ocean in the world are fish, and the rest are cetaceans, crustaceans and molluscs. There are many kinds of fish, including 1500. Fish is a treasure with high nutritional and economic value. It contains a lot of protein and tastes delicious. It is said that eating fish can make people's brains smart, and some of them have medical value and are valuable raw materials for fine chemicals.
In aquatic products, fish, shrimp and crab are always in the same breath. They are not only delicious food on the table, but also can extract many useful things from their crustaceans and are widely used in industry. Among them, a krill growing in the Antarctic is known as "the popular food of 2 1 century" because of its amazing resources and high nutritional value, and it is the object swallowed by Antarctic whales. Feeding krill to sperm whales is also an anecdote.
In the ocean, one part can not be ignored, that is, marine microorganisms, mainly bacteria, actinomycetes, snow mushrooms, yeasts, viruses and so on. They are numerous and unevenly distributed. Assuming that there are no microorganisms in the ocean, all substances in the ocean cannot be recycled, but their activities also cause certain losses to fishery production. Recent studies have shown that some special bioactive substances can be extracted from marine microorganisms, which has a miraculous effect on treating diseases.
An American author raised the question: "Who will feed China people in the next century?" No country in the world has this ability, but the marine industry can share this task, and the traditional fishery has reached or exceeded its regenerative capacity, so people have to turn to the research on the development technology of marine living resources, and the huge marine living resources are waiting for the arrival of the development era.