Meiofauna represent the dominant numerical and biomass component of deep-sea benthic metazoans (Vincx et al. 1994; Cook et al. 2000; Danovaro et al. 2002a), and play an important ecological role as the main pathway of energy transfer to higher trophic levels. High pressure,

38.1 Introduction .......................................................................................................................... 351 38.2 Field Procedures ................................................................................................................... 352 38.3 Meiofaunal Biomass ............................................................................................................. 352

38.3.1 Laboratory Procedures ............................................................................................. 353 38.3.1.1 Equipment and Instruments ....................................................................... 353 38.3.1.2 Solution ...................................................................................................... 353 38.3.1.3 Sample Preparation for the Determination of Meiofaunal Taxa

Biomass ...................................................................................................... 353 38.3.1.4 Procedure ................................................................................................... 353

38.3.2 Notes ......................................................................................................................... 353 38.3.3 Calculations .............................................................................................................. 354

38.4 Nematode Biomass ............................................................................................................... 357 38.4.1 Laboratory Procedures ............................................................................................. 357

38.4.1.1 Sample Preparation for the Determination of Nematode Biomass ............ 357 38.4.1.2 Slide Preparation ........................................................................................ 357 38.4.1.3 Equipment and Instruments ....................................................................... 357 38.4.1.4 Methods for Preparation of Permanent Slides ........................................... 358 38.4.1.5 Methods for Preparing the Slides .............................................................. 358 38.4.1.6 Notes .......................................................................................................... 358

38.4.2 Nematode Biomass Determination ........................................................................... 359 38.4.2.1 Materials .................................................................................................... 359 38.4.2.2 Methods ..................................................................................................... 359 38.4.2.3 Notes ..........................................................................................................360

38.5 Meiofaunal Biomass .............................................................................................................360 38.5.1 Direct Methods .........................................................................................................360 38.5.2 Indirect Methods .......................................................................................................360