Spatial and temporal variation of the benthic macrofauna in a grossly polluted estuary from southwestern Spain

Abstract

The spatial-temporal variation of subtidal macrofauna communities of the OdielTinto estuary, one of the most polluted areas in the world, was studied along a sampling period of 4 years (and 3 sampling events). This system has shown typical water and sediment characteristics of estuarine areas although the inner stations showed high concentrations of heavy metals. The structure of the macrofauna community was associated with granulometry, the percentage of organic matter and the heavy metals.Like in other estuaries, the community was dominated by polychaetes (especially by small size opportunistic taxa), meanwhile the crustaceans were the least abundant. Some changes during the sampling period were: slight increment in richness and diversity; greater presence of molluscs and crustaceans in the inner zones; a more homogeneous spatial distribution of opportunistic taxa and a higher number of taxa involved in the differences among the estuary areas. The period of study does not allow assuring that these changes have been due to a true improvement or to natural cycles of the communities in naturally stressed systems. So that it would be necessary the establishment of a long-term monitoring programme to study the evolution of the macrofauna communities to state if the corrective measures could achieve an improvement of this environment. This programme should focus on the study of macrobenthic community's structure and on those selected parameters which have been the major structuring factors for these communities.

Relationship between structure of macrobenthic assemblages and environmental variables in shallow sublittoral soft bottoms

“…Moreover, many studies have focused in strongly anthropogenic areas (e.g. Lu, 2005;Sánchez-Moyano et al, 2010;Nishijima et al, 2015).…”

Long-term temporal and spatial variation of macrobenthos in the intertidal soft-bottom flats of two small bights (Chupa Inlet, Kandalaksha Bay, White Sea)

“…For Pygospio elegans, Chironomus salinarius, Scoloplos armiger, Littorina saxatilis, and Tubifex costatus the importance of the Bight effect was higher than within-bight differences. One possible explanation is that these species could respond to the differences in physical conditions between locations, which is often the case for the large-scale ([100 m) variation (Legendre et al, 1997;Thrush et al, 1997a;Ysebaert & Herman, 2002;Giménez et al, 2005;Sánchez-Moyano et al, 2010).…”

“…Perhaps the main reason is that the use of several temporal scales comes at the expense of low spatial replication that reduces the confidence in results. Most multi-scale studies use several spatial and single temporal scale (Jenkins et al, 2000;Lawrie & McQuaid, 2001;Edgar & Barrett, 2002;De Biasi et al, 2003;Azovsky et al, 2004;Norén & Lindegarth, 2005;Giménez et al 2005Giménez et al , 2006Commito et al, 2006;Sánchez-Moyano et al, 2010). However, there are few long-term studies using several spatial scales (e.g., Ysebaert & Herman, 2002;Middelboe et al, 2003) and a few studies that combine several spatial and temporal scales simultaneously (e.g., Caffey, 1985;Chapman, 2002;Porri et al, 2006).…”

Benthic macrofaunal communities along an estuarine gradient in the Jiaojiang River estuary, China

“…The macrofaunal communities in the JRE were similar in several aspects to anthropogenic disturbed communities elsewhere, such as Seine estuary and Odiel--Tinto estuary (Desroy et al, 2007;Sánchez-Moyano et al, 2010;Shou et al, 2012Shou et al, , 2013. Shannon diversity (an average of less than 0.87 per station) and species richness (an average of less than 5 taxa per station) were generally low, and among the dominant taxa were polychaetes and bivalves.…”