Conclusion
By bridging the bottom-up energetic processes and top-down cascading
effects, our study contributes to reconciling food web studies using
different currencies, e.g., energy and population size. Our findings
advocate an energetic perspective in ecosystem management based on
trophic cascade theory, where strategies should be designed according to
the energetic dynamics of the focal system (Barnes et al. 2018).
Our study serves as a benchmark for future research on more complex
ecosystems over larger scales. In particular, in diverse food webs,
energy transfer efficiencies between trophic levels are jointly
determined by herbivore diversity and composition (e.g., in our
experiment), plant (Behl et al. 2012; Buzhdygan et al.2020) or predator diversity (Griffin et al. 2008), as well as
abiotic factors (Barneche et al. 2021; Eddy et al. 2021).
Disentangling the influences of these processes is challenging but key
to understanding the feedback between energetic processes and trophic
interactions in natural ecosystems. Moreover, over long timescales,
eco-evolutionary dynamics may alter species properties, e.g.,
anti-predation trait (Vestheim & Kaartvedt 2006) and thus food web
energetics. Empirical and theoretical studies with respect to these
directions should further contribute to a mechanistic understanding of
the responses of multitrophic communities to environmental changes.