What are the destruction of biological resources (not less than 250 words)

Marine living resources have been seriously damaged

The ecological environment of China's waters tends to deteriorate, and the abundance of marine living resources has been sharply reduced. The main problems faced by the marine fisheries are: over-catching of fish, and the decline of traditional fishery resources. The main reasons for this situation are the lack of planning and management, uncontrolled fishing, and increased pollution of the marine environment. In some estuaries, bays and shallow coastal areas, the ecological environment has deteriorated as a result of inappropriate damming of rivers, enclosure of the sea to make fields, construction of coastal projects and sewage disposal, which have exacerbated the decline in fishery resources. In addition to the serious destruction of fishery resources along the coast, other biological resources have not been properly protected. For example, in Jiaozhou Bay of Shandong Province, there were 141 species in 1963, 30 species in the 1970s, and only 17 species in the early 1980s. Some rare creatures, such as the Chinese white dolphin, dugong, spotted dolphin, sea turtles, amphioxus, etc., the decrease is more obvious, almost on the verge of extinction.

1, the sea was polluted to varying degrees

Oil is the most important pollutant in the sea water offshore, the scope of pollution is relatively wide, the East China Sea offshore area and the Bohai Sea part of the sea area of the harbor and estuary pollution is more serious. Oil pollution can not only make fish, shrimp, shellfish and other seafood tasteless, serious toxic effects. Oil pollution will also deteriorate the environmental quality of the seaside scenic spots and sea bathing beaches, affecting the excursion and rest and recuperation activities. 1980 to 1995, China's waters found a certain scale of the sea surface oil spill events 115. Because of the pollution of fish and shrimp spawning, reproduction and resource decline and other chronic impacts caused by the loss is estimated to reach billions of dollars a year.

Heavy metal pollution is mainly found in Jinzhou Bay, Liaohe estuary, Pearl River estuary and other near-shore sea areas. Heavy metals are easy to accumulate in the substrate, not easy to degrade, often enriched by organisms, and are a potential threat to human health.

Special ecosystems have been damaged, the island ecological environment deterioration

Coral growth is extremely slow, the rate of reef-building is only 1 ~ 3mm / a, once destroyed, and then restoration is difficult. However, due to the digging of reefs to make crafts and burn lime, China's coral reef resources are seriously damaged. Hainan Island, 80% of the coral reefs along the coast have been damaged to varying degrees. Both coastal barriers, but also fish and shrimp habitat breeding place of mangrove forests, due to large-scale land reclamation and wanton logging, the area of a sharp decline in the country's existing mangrove forests only 20,000 hm2. also has a high economic and ecological value of the coastal mudflat wetlands, but also in the large-scale reclamation of the serious damage, the cumulative loss of mudflat wetlands of about more than 1 million hm2, equivalent to the original mudflat wetlands of the half. Natural forests and coastal mangrove forests on many islands have been severely damaged, and the mining of bird droppings, excessive bird catching, excessive quarrying and dumping of industrial wastes have deteriorated the ecological environment of the islands.

-From "Marine Resource Utilization and Conservation" Lecturer: Yang Jun