Effects of land use on annelid assemblages in Pampean wetlands

Abstract

Context. Land use significantly affects wetlands, altering various biotic components and threateningbiodiversity. Aims. This study assessed the ecological status of Pampas wetlands under differentland uses by examining environmental characteristics and annelid assemblages. Methods. Fourwater systems in the Argentine Pampas were surveyed, including riverine wetlands and upstreamand downstream sections affected by urbanisation, intensive agriculture, or extensive livestockfarming. Key results. Multivariate analysis showed correlations among environmental factors andsites, whereas PERMANOVA analysis showed density variations among streams, sections, and landuses, although species richness and diversity remained consistent within each stream. In total, 42annelid species and morphotypes were identified and linked with various environmental factors.Conclusions. Enchytraeidae were correlated with nitrate and phosphorus concentrations, whereasLimnodrilus species and Tubifex tubifex were associated with nitrites, ammonium, vegetationcoverage and fine sediments. Species such as Pristina spp., Aulophorus costatus, Dero spp. andAulodrilus pigueti preferred sandy sediments enriched with organic matter and higher currentvelocities, indicating their potential as indicators of anthropogenic impact. Implications. Thesefindings highlighted the importance of annelid assemblages in wetland monitoring and underscorethe need for integrated watershed management and sustainable planning to protect wetlands.