关键词: 退化生态系统, 湿地, 生态恢复, 生态管理, 生物检验

Abstract: Influenced by human and natural disturbance,such as industrialization,urbanization and earth greenhouse effect,Hackensack Meadows,a wetland locating at the Northeast New Jersey,is facing many ecological stresses.Wetland area has shrunk two thirds in recent centuries. Landscape was fractured into12by roads,city and industrial zone.And the composition and structure of ecosystems became simple.At the same time,water contamination is becoming serious.Foreign species have been dominating more and more native wetland vegetation,and many native species disappeared.The wetland ecosystem had degraded sharply.In order to enhance the wetlands,conserve biodiversity and improve the environmental condition in this area,the New Jersey Wetland Commission and three other organizations in America set up a project(the special district management)to save the rest wetlands.The ecological restoration and management projects of Harrier meadow,Mill Creek marsh and Skeetill Creek marsh,a part of the project,were supported by the New Jersey Commission and had been finished in1998.Goal of the projects was to restore its original ecosystem,including ecological environment and biome.And the restoration engineering included rebuilding complex landscape,transplanting native plant,transporting substrates,restoring tidal pattern,reconstructing mitigating and nesting habitats for bird etc.And our research group conducted the management of their ecological restoration process.Growth of vegetation,control of foreign species and restora-tions of ecosystem biodiversity were chosen by us as the bioassays to indicate restoration trend of ecosystem function and sampled in the three restoration sites every season.Then database was set up and analyzed.Restoration process was evaluated two times every year for further management.The management of vegetation included investigation of composition and structure of vegetation,analyses of factors affecting restoration process and application of corresponding technology.The management of foreign species focused on mechanism of their population spread and methods to control the invaders.In the aspect of biodiversity,the enhancement of animal species and relati-onship between vegetation and animal biodiversity were studied especially.It was shown that the primary restoration on the three sites followed the restoration design on the whole.But the vegetation in Harrier meadow restored faster than other two sites due to the rich biodiversity surrounding the restoration site.The animal biodiversity in Mill Creek and Skeetkill Creek restored slowly as their vegetation was dominated by foreign species Phragmites australis and Solidago sempervirens.Restoring tidal pattern in restoration sites,harvesting overground parts and cleaning seedling could effectively control the spread of Phragmites and facilitate the growth of native plant species.

Key words: degraded ecosystem, wetlands, ecological restoration, ecological management, bioa-ssay