Based on shell concentrations of the planktonic foraminifera Neogloboquadrina pachyderma from vertically resolved plankton tow samples during cruises ARK-IV/3, ARK-XI/1, ARK-XIII/2, ARK-XV/1, ARK-XV/2, MSM44, MSM66, M21/4, M21/5, M39/4, MSM09/2, NEWP-92, NEWP-93, PS93.1, PS31, PS78, the base of the productive zone is calculated. The calculation is based on the assumption that the base of productive zone is located where shell concentration begins to substantially decline and it is calculated after Lončarić et al. (2006).

The calculation of the base of the productive zone of N. pachyderma is based on the assumption that the base of productive zone is located where shell concentration begins to substantially decline, which was determined visually. For all cases in which abundances decrease with depth, it is calculated after Lončarić et al. (2006): Z_BPZ=(C_n-C_exp)/C_(n-1) (Z_n-Z_(n-1) )+Z_(n-1)All BPZ that is based on this equation have the remark “regular” in the column of calculation method. As the equation is constructed for cases where the shell concentration decreases with depth, it cannot be applied where this is not the case (such as where there is a distinct subsurface maximum), as the estimated BPZ would appear to lie below the depth interval of the transition zone. In those cases, the BPZ was defined as the bottom depth of the transition zone (labeled as range end).