A study on the response of waterbird diversity to habitat changes caused by ecological engineering construction

Abstract

Wetland degradation is a major factor in the decline of biodiversity. Ecological engineering construction efforts, such as water diversion, have been the main method of wetland restoration. To reveal the effects of biodiversity conservation and ecological engineering construction in the semiarid regions of China, waterbird surveys were carried out 2 years before and 8 years after the construction of the ecological engineering project discussed in this study. The relationships among waterbirds and habitat landscape patterns, hydrology and vegetation conditions were analyzed. The impacts of ecological engineering on habitats and waterbird diversity were revealed. The results showed that (1) there were significant changes in land use, hydrological distributions and vegetation cover in the study area before and after the construction of the ecological project. The quality of waterbird habitats after the construction project was better than that before construction. However, there were fluctuating conditions. (2) The areas of water bodies and marshes were positively correlated with the number and diversity of waterbirds. However, increases in arable land, forestland, grassland and saline land can stress rare waterbirds. Changes in water levels, water body areas and vegetation cover in the conservation area all directly affect the availability of waterbird habitats, which can affect waterbird diversity. The wetland water level is the most important impact factor. (3) The annual water diversion volume in the study area is 5.00 × 107 m3. When the water level is maintained at approximately 1.5-2.5m, the number of waterbirds remains stable. This study can provide scientific guidance and a methodological basis for the construction of ecological projects with waterbirds as protected targets.