impact of bioturbation by Arenicola marina on microbiological parameters in intertidal sediments

Abstract

The impact of bioturbation by the lugworm Arenicola manna on sediment microflora and biochemical activities was investigated in intertidal sediments of the North Sea. Burrow walls and fecal casts were compared with surface and subsurface sediment surrounding the burrows. At the main study site burrow walls contained twice as much organic matter as the sediment surface. Viable counts of aerobic proteolytic and chitinolytic bacteria peaked at external and internal boundary layers (sediment surface and burrow walls). Burrow walls showed maximal bacterial production (incorporation of tritiated thymidine into DNA), maximal microheterotrophic activity (incorporation and mineralization of glucose and acetate) and highest levels of certain hydrolytic enzymes (alkaline phosphatase and sulfatase). Rates of chemoautotrophic COz fixation in both burrow walls and surrounding subsurface sedment were 3 to 4 times higher than at the sediment surface, suggesting a short-cucuited CO2 turnover driven by an elevated catabolism. In a second, more polluted study area, burrow walls were again the main site of microheterotrophic activity, but only minor differences were noted for CO2 fixation. Biogeochemical consequences of bioturbation by A, marina could be understood essentially as a shifting of catabolic and anabolic microbial activity peaks from the top to subsurface layers, where burrow walls showed the most conspicuous effects. Nevertheless, protease peaks in the fecal casts indicated also that this shifting pattern can be reversed for certain parameters.

Increase in Alphaproteobacteria in association with a polychaete, Capitella sp. I, in the organically enriched sediment

“…Microbial abundance tends to increase along the inner walls of the burrows (Alongi, 1985;Aller and Aller, 1986;Lucas et al, 2003;Wu et al, 2003;Wada et al, 2006) and around the feces excreted from the animals (Hargrave, 1976;Plante and Wilde, 2001). Various bacteria actively facilitate the decomposition of the organic matter at these sites (Aller et al, 1983;Reichardt, 1988).…”

Distribution and abundance ofAbarenicola affinis(Arenicolidae, Polychaeta) in tidal inlets of Otago, New Zealand

“…Baumfalk 1979;Huettel 1990;Riisgard et al 1996;Banta et al 1999;Kristensen 2001;, and associated biota (e.g. Brenchley 1981;Wilson 1981;Reichardt 1988;Flach 1992;Riisgard & Banta 1998;Reise 2002;.…”

Ichnological analysis of the Pleistocene Dwarka Formation, Gulf of Kachchh: tracemaker behaviors and reworked traces

“…Similarly, in an experimental work on the burrows of the Arenicola marina from the North Sea, Reichardt (1988) indicated that the burrow walls and faecal cast showed higher concentration of organic matter when compared with surface and subsurface sediment surrounding burrows, especially the burrow wall contained twice organic matter as the sediment surface. Similarly, Abed-Navandi et al (2005) conducted a detailed analysis of the burrows of the thalassinidean shrimps from Bermuda area.…”

“…In recent sediments, burrow walls and burrow fills are the locations of nutrient enrichments (Abed-Navandi, Koller, & Dworschak, 2005), bacterial enrichment (Aller & Yingst, 1985;Yingst & Rhoads, 1980) or higher concentration of organic matter (Reichardt, 1988). Such nutrient or food-rich locations after the death of trace maker become preferential foraging location.…”