钦州湾越冬鸻鹬类对不同生境利用分析

2008年12月至2009年1月及2011年12月至2012年1月先后两次对钦州湾的越冬鸻鹬类进行了调查,对越冬鸻鹬类退潮后在各类型生境的分布情况和原因进行了分析,以期为制定有效保护越冬鸟类及其生境的措施提供科学依据。结果表明,在不同的天气情况下退潮后各生境内记录到的鸻鹬类物种数和种群数量均不同,钦州湾不同生境鸻鹬类结构特征随天气变化改变。相似性比较显示,晴天各生境中鸻鹬类相似性指数最高的是盐田-养殖塘生境和农田生境,相似性指数为0.96;鸻鹬类相似性指数最低的是红树林滩涂生境和光滩生境,相似性指数为0.49。阴冷天气各生境中鸻鹬类相似性指数最高的是光滩生境和盐田-养殖塘生境,相似性指数为0.79;最低是红树林滩涂生境和光滩生境,相似性指数为0.52。分析表明人类活动的干扰对越冬鸻鹬类生境选择的影响较大。

Habitat Selection Analysis of Wintering Shorebirds at Qinzhou Bay, Guangxi

During two winters of December 2008 to January 2009 and December 2011 to January 2012, we studied the habitat selection of wintering shorebirds at Qinzhou Bay, in Guangxi of south China. We investigated the distribution of wintering shorebirds in different habitat types during the low tide and analyzed the reasons, in order to make effective measures to protect wintering birds and their habitats. Four kinds of habitat were divided in our study area, 1) Mangrove tidal flats, 2) Sandy beach, 3) Salt pan-aquacultural pond, 4) Farmland. In each habitat, 2 lines of 3 000 m were set up for the investgations, with the methods of line transect and fixed-point observation. During the censuses, we walked at a speed of 1-1.5 km/h, and counted the birds within the scope of 50 m on both sides with the help of 8 times binoculars. For data processing, 5 types of indicators were used to measure and analyze the shorebirds'distribution in each habitat, including species, species diversity index, species evenness index, species dominance index and similarity index. Totally 27 species were identified in Qinzhou Bay. The results showed that the shorebird composition and density were different in different weather conditions or different habitats during low tide. Shorebirds structure of different habitats in Qinzhou Bay varied with weather changes. For similarity comparison, during the sunny days, the salt pan-aquacultural pond and farmland had the highest shorebird similarity with the index of 0.92, and the mangrove tidal flats and sandy beach had the lowest shorebird similarity with the index of 0.49. During the wet and cold days, the sandy beach and salt pan-aquaculture pond had the highest shorebird similarity with the index of 0.79, and the mangrove tidal flats and sandy beach had the lowest similarity with the index of 0.52. Our results showed that human activities caused heavy disturbances to the shorebirds, and affected their habitat selection.