TY  - JOUR
A1  - Kath, Nadja J.
A1  - Boit, Alice
A1  - Guill, Christian
A1  - Gaedke, Ursula
T1  - Accounting for activity respiration results in realistic trophic transfer efficiencies in allometric trophic network (ATN) models
T2  - Theoretical ecology
N2  - Allometric trophic network (ATN) models offer high flexibility and scalability while minimizing the number of parameters and have been successfully applied to investigate complex food web dynamics and their influence on food web diversity and stability. However, the realism of ATN model energetics has never been assessed in detail, despite their critical influence on dynamic biomass and production patterns. Here, we compare the energetics of the currently established original ATN model, considering only biomass-dependent basal respiration, to an extended ATN model version, considering both basal and assimilation-dependent activity respiration. The latter is crucial in particular for unicellular and invertebrate organisms which dominate the metabolism of pelagic and soil food webs. Based on metabolic scaling laws, we show that the extended ATN version reflects the energy transfer through a chain of four trophic levels of unicellular and invertebrate organisms more realistically than the original ATN version. Depending on the strength of top-down control, the original ATN model yields trophic transfer efficiencies up to 71% at either the third or the fourth trophic level, which considerably exceeds any realistic values. In contrast, the extended ATN version yields realistic trophic transfer efficiencies 30% at all trophic levels, in accordance with both physiological considerations and empirical evidence from pelagic systems. Our results imply that accounting for activity respiration is essential for consistently implementing the metabolic theory of ecology in ATN models and for improving their quantitative predictions, which makes them more powerful tools for investigating the dynamics of complex natural communities.
KW  - Food web
KW  - Trophic transfer efficiency
KW  - Allometric trophic network model
KW  - Allometry
KW  - Energy transfer
KW  - Activity respiration
Y1  - 2018
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/51448
SN  - 1874-1738
SN  - 1874-1746
VL  - 11
IS  - 4
SP  - 453
EP  - 463
PB  - Springer
CY  - Heidelberg
ER  -