A case of successful restoration of a tropical wetland evaluated through its Odonata (Insecta) larval assemblage
Un caso de éxito en la restauración de un humedal tropical mediante la evaluación del ensamble de larvas de Odonata (Insecta)
Wetlands are important wildlife habitats that also provide vital services for human societies. Unfortunately, they have been disappearing due to human activities such as conversion to farmland, pollution, habitat fragmentation, invasion of alien species, and inappropriate management, resulting in declines in species diversity, wildlife habitat quality, and ecosystem functions and services. In some countries, many programs and actions have been undertaken to reverse the rate of wetland loss by restoring, creating and constructing new wetlands. We report on the assessment of Odonata larvae from a tropical and putatively restored wetland located in the La Mancha Biological Station, CICOLMA (LM, Ramsar site #1336), Veracruz, Mexico. Larval surveys were performed during the 2010 and 2011 dry and rainy seasons in both LM and a reference site, Cansaburro (CB), located approximately 2 km South of LM. Twelve samples were collected during each survey using a D-frame aquatic net (0.2 mm mesh size), sweeping 1 m2 areas along shorelines using a random design. The effect of site, season and year on Odonata larval abundance was explored and diversity and abundance patterns of the assemblages were compared. A total of 3 718 larvae from 25 species (five Zygoptera and 20 Anisoptera) in 14 genera and three families were collected from both wetlands. Species number was equal in both wetlands although abundance was significantly higher in LM. Renyi´s diversity profiles and species abundance patterns (rank abundance curves) in both sites were similar, suggesting an apparent recovery at LM. Differences in species composition (sites shared 13 species), and species dominance between both assemblages were observed and were related to differences in the aquatic plant structure between both wetlands as a result of extensive plant management in LM and cattle grazing in CB. Most evidence derived from this work shows that the LM wetland may be recovered. Abstract. A case of successful restoration of a tropical wetland evaluated through its Odonata (Insecta) larval assemblage. This article provides numerical study of the Odonata larvae from a tropical recovered wetland located in La Mancha (LM, Ramsar site 1336), Veracruz, Mexico. Larval surveys were performed during the dry and rainy seasons of 2010 and 2011 and compared to a reference site in the locality of Cansaburro (CB). The effect of site, season and year on Odonata larval abundance was explored and diversity, richness, evenness and abundance distributions of both assemblages were compared. A total of 3,718 larvae from 25 species (five Zygoptera and 20 Anisoptera) in 14 genera and three families were collected from both wetlands. Species number was equal to both wetlands although abundance was significantly higher in LM. Diversity and species abundance patterns in both sites were similar although Shannon diversity was significant and slightly higher in the reference site. Differences in species composition and species dominance order between both assemblages were observed and addressed to differences in the aquatic plant structure between both wetlands which is mainly affected by management in La Mancha and by cattle grazing in Cansaburro. While the diversity of La Mancha was lesser than the reference site, most of the results of this investigation showed that La Mancha wetland has been successfully recovered.
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- Revista de Biología Tropical [2109]