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squashed Reclamation of large areas
In the wetland reserve， we may feel joyful for the large area of wild sight， but we don’t know that a lot of wetland curl up in the middle of the gathering farmland， not as vast as before for long. China has a large area of wetland， but only a few are classified as the wetland reserve or wetland park luckily. As for other wetlands， some of them are used as agricultural or industrial lands， some are used for infrastructure construction.
Since the 1950 s， the national wetland reclamation area is 10 million hectares. the Yangtze river delta， the pearl river delta， the jianghuai plain， the large areas of paddy fields in chengdu plain became cities and highways； many scenic wetland in the Northeast became cultivated lands； many coastal places blew up the hills near the sea to the heights， filled the earth-rock into the transition sea beach wetland， making a lot of wide tidal flats wetlands disappearing permanently. More worryingly， owing to the lack of understanding of the importance of wetlands， some local government departments even encouraged the reclamation of wetlands， and provide economic compensation.
be ransacked Overfishing acquisition
When you see the clear lake at the wetland， with no fish in the water， no birds in the sky. Then this wetland may have been fished out， the birds also don’t want to come to feed. Maybe you will feel sad and disappointed， but don’t forget， our task is to rebuild a paradise for birds and fish.
Wetland is known as the "biological treasure"， but the overfishing acquisition ransacked the rich products of the wetlands， eventually not only affects the biodiversity of wetlands， but also destroys the ecological balance of wetland health. According to a study of the state forestry administration， among the 323 important wetlands by monitoring， 40.7% of the lakes， 26.4% of the coastal wetlands and 19.8% of the swampy wetlands have been threatened by overfishing. In some inland lake type wetlands by contracting， the big and small fishes are all fished by contractors， a large number of small fishes are used as a mink， raccoon feed； the fishing net mesh of many fishermen is more and more close， that salving the offshore fishes and shrimps neatly； in some areas people pump water to fish， steam shrimps， the cruel ways of fishing bring to the wetland’s fish and shrimp great calamity. Drain the pond to get all the fish， eventually people will have no fish to eat. Poisoned The terrible pollution toxins
In the wetlands in the city， under the green reeds maybe the urban sewage， occasionally floating some dead fish， that is the traces of contamination of the wetland. The wetland itself has a strong purification function， but the overload of waste water， junks will make it being polluted. Along with the urban construction， a lot of industrial waste water， waste residue and sewage are discharged into the wetlands； the rainfall brings the waste， pollutions， agricultural chemical fertilizer， pesticide and animal waste into the river and the wetlands. The toxic substances may do harm to aquatic organisms， and excess nutrients can lead to eutrophication of water body， and make the algae outbreaks， so the fish and aquatic plants dies from lack of oxygen.
In addition， the breeding pollution is also harmful. Take the sea cucumber farming as an example， during the process of the sea cucumbers’ mudflat aquaculture， the medicine is taken since the seeding to producing， these drugs can kill a large number of shellfish and other creatures， seriously damage the ecological balance of the coastal wetland.
Hacked Dangerous exotic killer
The invasion of exotic harmful plants is already a global phenomenon， is also one of the three most pressing environmental problems of the 21st century. once settled down in the wetlands， these exotic killers quickly spread and bloom， occupy the territories， drive away the local plants in the wetlands. The famous smooth cordgrass native to the Atlantic coast of the United States and the gulf of Mexico， invades from the coastal areas， seriously damaged the 4 important international wetland including the Shanghai Chongming Dongtan nature reserve. The Solidago Canadensis， crassipes， alternanthera grass are the same notorious， they are widely distributed in southern China provinces， with big harm. In fact the “exotic” not only refers to the foreign country， it means besides the original living areas. The most common poplar in northern China change the simple and honest face in Dongting lake wetland， reveals its arbitrary nature， causing the rapid demise of the native vegetation community. To treat the invasive plants， we can have differential treatment according to its characteristic. After fully assess of its risks， we can carry on its reasonable use. The four important crisis are all related to human， it will be a big problem for us to deal with the relations among population growth， economic development and wetland protection. In addition， there is lack of effective guarantee system and legislation in the wetland protection， which is also the difficulty on the wetland management.
In the wetland reserve， we may feel joyful for the large area of wild sight， but we don’t know that a lot of wetland curl up in the middle of the gathering farmland， not as vast as before for long. China has a large area of wetland， but only a few are classified as the wetland reserve or wetland park luckily. As for other wetlands， some of them are used as agricultural or industrial lands， some are used for infrastructure construction.
Since the 1950 s， the national wetland reclamation area is 10 million hectares. the Yangtze river delta， the pearl river delta， the jianghuai plain， the large areas of paddy fields in chengdu plain became cities and highways； many scenic wetland in the Northeast became cultivated lands； many coastal places blew up the hills near the sea to the heights， filled the earth-rock into the transition sea beach wetland， making a lot of wide tidal flats wetlands disappearing permanently. More worryingly， owing to the lack of understanding of the importance of wetlands， some local government departments even encouraged the reclamation of wetlands， and provide economic compensation.
be ransacked Overfishing acquisition
When you see the clear lake at the wetland， with no fish in the water， no birds in the sky. Then this wetland may have been fished out， the birds also don’t want to come to feed. Maybe you will feel sad and disappointed， but don’t forget， our task is to rebuild a paradise for birds and fish.
Wetland is known as the "biological treasure"， but the overfishing acquisition ransacked the rich products of the wetlands， eventually not only affects the biodiversity of wetlands， but also destroys the ecological balance of wetland health. According to a study of the state forestry administration， among the 323 important wetlands by monitoring， 40.7% of the lakes， 26.4% of the coastal wetlands and 19.8% of the swampy wetlands have been threatened by overfishing. In some inland lake type wetlands by contracting， the big and small fishes are all fished by contractors， a large number of small fishes are used as a mink， raccoon feed； the fishing net mesh of many fishermen is more and more close， that salving the offshore fishes and shrimps neatly； in some areas people pump water to fish， steam shrimps， the cruel ways of fishing bring to the wetland’s fish and shrimp great calamity. Drain the pond to get all the fish， eventually people will have no fish to eat. Poisoned The terrible pollution toxins
In the wetlands in the city， under the green reeds maybe the urban sewage， occasionally floating some dead fish， that is the traces of contamination of the wetland. The wetland itself has a strong purification function， but the overload of waste water， junks will make it being polluted. Along with the urban construction， a lot of industrial waste water， waste residue and sewage are discharged into the wetlands； the rainfall brings the waste， pollutions， agricultural chemical fertilizer， pesticide and animal waste into the river and the wetlands. The toxic substances may do harm to aquatic organisms， and excess nutrients can lead to eutrophication of water body， and make the algae outbreaks， so the fish and aquatic plants dies from lack of oxygen.
In addition， the breeding pollution is also harmful. Take the sea cucumber farming as an example， during the process of the sea cucumbers’ mudflat aquaculture， the medicine is taken since the seeding to producing， these drugs can kill a large number of shellfish and other creatures， seriously damage the ecological balance of the coastal wetland.
Hacked Dangerous exotic killer
The invasion of exotic harmful plants is already a global phenomenon， is also one of the three most pressing environmental problems of the 21st century. once settled down in the wetlands， these exotic killers quickly spread and bloom， occupy the territories， drive away the local plants in the wetlands. The famous smooth cordgrass native to the Atlantic coast of the United States and the gulf of Mexico， invades from the coastal areas， seriously damaged the 4 important international wetland including the Shanghai Chongming Dongtan nature reserve. The Solidago Canadensis， crassipes， alternanthera grass are the same notorious， they are widely distributed in southern China provinces， with big harm. In fact the “exotic” not only refers to the foreign country， it means besides the original living areas. The most common poplar in northern China change the simple and honest face in Dongting lake wetland， reveals its arbitrary nature， causing the rapid demise of the native vegetation community. To treat the invasive plants， we can have differential treatment according to its characteristic. After fully assess of its risks， we can carry on its reasonable use. The four important crisis are all related to human， it will be a big problem for us to deal with the relations among population growth， economic development and wetland protection. In addition， there is lack of effective guarantee system and legislation in the wetland protection， which is also the difficulty on the wetland management.