ABSTRACT
Metazoan meiofauna represent the most abundant class of pluricellular organisms of the marine benthos, reaching abundances comprising 105 to 106 individuals per m2 (100-1000 ind. 10 cm−2) and also a biomass of 1-2 g DW m−2 at depth >100 m (Rex et al. 2001). Metazoan meiofauna are the dominant component of the deep-sea benthic metazoans both in terms of abundance and biomass (Vincx et al. 1994; Cook et al. 2000; Danovaro et al. 2002), and they have an important ecological role, representing the main pathway of energy transfer to higher trophic levels (as key component of the diet of juvenile demersal sh species; Leguerrier et al. 2003). Meiofauna are also characterized by a high sensitivity to environmental changes due to the short generation time, high sensitivity to any changes in environmental conditions, and lack of pelagic larval dispersion (Bongers and Ferris 1999). The total abundance and biomass of meiobenthic assemblages are known to decrease with increasing water depth, and several studies suggest that food supply is one of the major factors controlling their distribution in the deep-sea sediments (Vincx et al. 1994; Danovaro et al. 2000; Galéron et al. 2001; Danovaro et al. 2008). On a macroscale (>1000 km), deep-sea faunal distribution is assumed to depend primarily on physical parameters
17.1 Introduction .......................................................................................................................... 149 17.2 Field Procedure ..................................................................................................................... 150
17.2.1 Sampling ................................................................................................................... 150 17.2.2 Storage of Meiofaunal Samples at −20°C ................................................................. 150
17.2.2.1 Equipment and Instruments ....................................................................... 150 17.2.2.2 Procedure ................................................................................................... 151 17.2.2.3 Notes .......................................................................................................... 151
17.2.3 Storage of Meiofaunal Samples Using Buffered 4% Formalin ................................ 151 17.2.3.1 Equipment and Instruments ....................................................................... 151 17.2.3.2 Solutions ..................................................................................................... 151 17.2.3.3 Procedure ................................................................................................... 151 17.2.3.4 Notes .......................................................................................................... 151
17.3 Laboratory Procedure ........................................................................................................... 152 17.3.1 Extraction .................................................................................................................. 152
17.3.1.1 Equipment and Instruments ....................................................................... 152 17.3.1.2 Solutions ..................................................................................................... 152 17.3.1.3 Procedure ................................................................................................... 152 17.3.1.4 Notes .......................................................................................................... 153
17.3.2 Sorting ...................................................................................................................... 154 17.3.2.1 Equipment and Instruments ....................................................................... 154 17.3.2.2 Solutions ..................................................................................................... 154 17.3.2.3 Procedure ................................................................................................... 154 17.3.2.4 Notes .......................................................................................................... 155
References ...................................................................................................................................... 159
(temperature, hydrodynamic regimes, and near-bottom currents; Thiel 1983; Thistle and Sherman 1985; Thistle et al. 1991; Lambshead et al. 2001; Mokievsky et al. 2004) and food source availability (Schaff et al. 1992; Vanreusel et al. 1995; Relexans et al. 1996; Brown et al. 2001; Gambi and Danovaro 2006), while at smaller spatial scales (meso-and local scale), oxygen, food availability, and interactions between organisms or between organisms and the microhabitat have been suggested to be increasingly relevant (Eckman and Thistle 1988; Tyler 1995; Snelgrove et al. 1996; Levin et al. 2001). Here we report the methods for sampling and the laboratory procedures to extract and to sort and count metazoan meiofauna.
