Re-evaluating primary biotic resource use for aquatic biomass production: a new calculation framework

The impacts of biomass production on primary biotic resources can be quantified through the amount of net primary production required to produce one unit of harvested biomass (SPPR- specific primary production required). Existing approaches calculate SPPR based on food chain theory, or on simplified food web structure. We present a new calculation framework that explicitly takes into account full food web complexity and show that the resulting SPPR for molluscs in the northern Gulf of St. Lawrence is 56 times higher than when food web structure is simplified. In addition, we show that our new framework can be coupled to quantitative food web modelling to examine how uncertainty on ecological data and processes can be accounted for while estimating SPPR. This coupled approach reveals that increase in the degree of heterotrophy by flagellates from 0% to 100% can result in 2-fold increase in SPPR estimates in the Barents Sea. It also reveals that the estimated SPPR (kg C-NPP kg C-fish-1) is between 3.9 (herring) and 5.0 (capelin) times higher than that estimated when adopting a food chain approach. Overall, our results make a plea for a quantitative integration of ecological processes and associated uncertainty, in biotic resource use assessment.

LUONG Duc Anh;  SCHAUBROECK Thomas;  DEWULF Jo;  DE LAENDER Frederik; 

2015-11-04

AMER CHEMICAL SOC

JRC95013

0013-936X,   

http://pubs.acs.org/doi/10.1021/acs.est.5b02515,    https://publications.jrc.ec.europa.eu/repository/handle/JRC95013,   

10.1021/acs.est.5b02515,