松嫩平原湿地环境问题及整治方略

Environmental Problems and Protection Countermeasures for the Wetlands in Songnen Plain,Oortheast China

松嫩平原湿地地处半湿润半干旱区,属中国典型的农牧交错区和生态脆弱带,以芦苇(Phragmites australis)湿地为主,是调蓄洪水、分配水资源、生态环境调节和小气候调节及农业生产的关键区,也是诸多珍稀水禽的栖息繁衍基地,分布着诸多国家重要湿地,因此对其合理开发利用及保护是实现松嫩平原持续稳定发展的关键。着眼于湿地的功能,从区域可持续发展的高度入手,深入剖析了松嫩平原湿地因人类不合理开发利用所面临的严重生态环境问题,并由此提出了可持续性管理及防治对策。

Songnen Plain is located in the ecological fragility from Songhuajiang River and Nenjiang River. A lot of inland zone in semi -arid area, and is an alluvial plain marsh wetlands are formed due to special natural environmental characteristics such as clay alluvial parent materials, low basin and so many rivers. These marsh wetlands perform such ecological functions as providing the habits for most rare and endangered water birds, acting as the key area for controlling floods, purifying pollutants adjacent to lands and keeping regional ecological safety and so on. There are many national important wetlands in this region, including lake wetland, Zhalong wetland, Momoge wetland, Keerqin Wetland ect. Moreover, Xianghai wetland, Chagan Xianghai and Zhalong wetlands have been listed in ＂international inportant wetland＂. The dominant wetland plants are Phragmites australi, Carex and Typha orientalis in these wetlands. Most wetland national or provincial natural reserves have been built for protecting wetland system and wetland biodiversity, since so many birds rely on the wetland habitats. Most wetlands in Songnen Plain have greatly degradated due to unreasonable utilization such as excess reclamation, digging channels and discharging etc. Wetland shrink is obvious and there have been lost 10×10^4hm^2 reed wetlands since 1970 s, which led to ecological service functions reduced or lost, and most birds or fishes disappeared due to habitats loss. Serious salinity and alkalinity of wetlands have occurred in this region, and sandy lands are expanding, with 56% potential sandy desertification lands and 36% proceeding sandy lands. The wetlands adjacent to sandy lands are facing with sandy threats. Wetland pollution is also more and more serious, resulting in water quality deterioration of wetlands. A lot of untreated waste water from industrial, agricultural and domestic sources has been directly discharged into wetlands, exceeding ecological capacity of wetlands. For example, most of lakes in Zhalong wetland have been heavier eutrophication, with Class V of water quality in Core zone. Xianghai Wetland has also been polluted by heavy metals from coal exploitation in upstream of Huolin river. The irrigation works upstream have led to water shortage of downstream wetlands, improving wetland degradation. Most of roads have been building in order to develop tourism, which led to wetland landscape fragmentation and biodiversity reduce. In addition, the present wetland management systems are not advantageous to wetland protection. The countermeasures and advices are put forward for sustainable management and prevention and cure for wetlands in Songnen Plain. Firstly, it is important to strengthen artificial control of water resources and make the best of flood water in order to ensure wetland ecological water. Secondly, it is necessary to develop herd under ecological safety in order to control salinity, alkalinity and sandy desertification. Thirdly, it is advised to advocate ecological tourism and ecological culture in order to protect wetland integrality and stability. Fourthly, High- efficiency wetland management system and perfect eco habitat safety of water birds. Lastly, wetland pollution must be logical monitoring system must be built to protect solved and wetland ecological function planning is also advised in order to keep the harmony of human and wetlands.