福建洛阳江口红树林湿地大型底栖动物多样性及季节变化

基于2013-2014年福建洛阳江口红树林湿地的周年调查资料, 研究了该湿地大型底栖动物的物种多样性现状、季节变化以及红树林恢复对底栖动物群落的影响。本次调查共鉴定大型底栖动物7门78种, 环节动物和节肢动物种类最为丰富, 节肢动物对总生物量贡献最大, 短拟沼螺(Assiminea brevicula)为本区第一优势种。林区底栖动物的密度和生物量明显低于光滩, 部分优势种仅在林区出现, 此外, 林区群落与光滩有显著差异。本区底栖动物的密度高值出现在冬、春季, 生物量高值出现在春、夏季, 群落结构季节变化明显。本区底栖动物种类组成特点反映出洛阳江口红树林处在年轻期, 群落的季节变化可能跟优势种的繁殖特点有关。研究结果也表明红树林植被会影响底栖动物群落结构, 林区群落已然不同于光滩, 与2009年调查结果相比, 林区底栖动物密度虽明显下降, 但褶痕拟相手蟹(Parasesarma plicata)数量增加, 是优势种之一。洛阳江口红树林和光滩支撑着不同的生物组成, 因此, 红树林恢复应当保持栖息地的多样性/异质性。

Macrobenthic diversity and seasonal changes in the mangrove swamp of Luoyangjiang Estuary,Fujian Province

Based on a year round survey conducted in the mangrove swamp of Luoyangjiang Estuary in Fujian from August 2013 to April 2014, macrobenthic diversity, seasonal changes, and the impact of mangrove rehabilitation on the macrobenthic community were analyzed. We recorded a total of 78 species from 7 phyla in the study area and the community was dominated by annelids and arthropods. The gastropod, Assiminea brevicula (Assimineidae), was the most dominant species and was more abundant in mangrove forests than in mudflats. ANOSIM analysis showed that faunal communities were significantly different between mangrove forests and mudflats, with the former characterized by much lower macrobenthic density and biomass. Moreover, some of dominant species, such as Parasesarma plicata and Phascolosoma arcuatum, were only found in mangrove forests. Higher value of macrobenthic density was found in winter and spring, while mean biomass was higher in spring and summer. Significant differences in macrobenthic communites were observed among seasons except between winter and spring. The present study demostrated that, species composition of the mangrove macrobenthos indicated characteristics of a young mangrove plantation and seasonal changes in macrobenthic communities might be due to different breeding seasons of the dominant species. Mangrove vegetation had a noticeable impact on macrobenthic communities, as evidenced by significant difference in macrobenthic communites between the two habitats. Density of macrobenthos in mangrove forests was much lower than that found in 2009, but the sesarminid crab Parasesarma plicata became much abundant. Since mangrove forests and mudflats support different species composition of macrobenthos, planning is needed in mangrove rehabilitation for the protection of habitat diversity and heterogeneity.