Integrating ecosystem engineering and food webs

Abstract

Ecosystem engineering, the physical modification of the environment by organisms, is a common and often influential process whose significance to food web structure and dynamics is largely unknown. In the light of recent calls to expand food web studies to include non-trophic interactions, we explore how we might best integrate ecosystem engineering and food webs. We provide rationales justifying their integration and present a provisional framework identifying how ecosystem engineering can affect the nodes and links of food webs and overall organization; how trophic interactions with the engineer can affect the engineering; and how feedbacks between engineering and trophic interactions can affect food web structure and dynamics. We use a simple integrative food chain model to illustrate how feedbacks between the engineer and the food web can alter 1) engineering effects on food web dynamics, and 2) food web responses to extrinsic environmental perturbations. We identify four general challenges to integration that we argue can readily be met, and call for studies that can achieve this integration and help pave the way to a more general understanding of interaction webs in nature. Why integrate ecosystem engineering and food webs?The study of food webs has long been central to basic and applied understanding of stability and change in community organization and ecosystem functioning (Pimm 1982, Montoya et al. 2006, Mougi and Kondoh 2012. Recently, however, there have been calls to broaden the scope of food web studies to incorporate non-trophic interactions (Olff et al. 2009, Bascompte 2010, Kéfi et al. 2012; i.e. move toward the study of interaction webs that may better reflect reality (Ings et al. 2009). Ecosystem engineering, the physical modification of the environment by organisms (Jones et al. 1994(Jones et al. , 1997, may well be the most common and influential kind of non-trophic interaction. Research over the last two decades has revealed that ecosystem engineering is nearly as ubiquitous as trophic interactions (Wright and Jones 2006, Hastings et al. 2007, Jones and Gutierrez 2007, and has the potential to alter the architecture and dynamics of entire interaction webs (Olff et al. 2009, Golubski and Abrams 2011, Kéfi et al. 2012 and many ecosystem processes (Dangerfield et al. 1998, Gutiérrez and Jones 2006, Lavelle et al. 2006. Because species are affected by their physical environment, and because ecosystem engineers are food web members and modify the physical environment, their dual role is potentially one of the most important bridges between the trophic and non-trophic.Current food web models are parameterized on the basis of trophic connections. Any engineering effects on OIKOSAll species are affected by their physical environment. Because ecosystem engineering species modify the physical environment and belong to food webs, such species are potentially one of the most important bridges between the trophic and non-trophic. We examine how to integrate the so far, largely independent research area...

An ecological engineer maintains consistent spatial patterning, with implications for community‐wide effects

“…The same general reliance on two types of data was taken in work estimating the effects of spatial patterning of termite mounds on several community and ecosystem responses (Fox-Dobbs et al 2010, Pringle et al 2010. Consequences of spatial pattern have been observed at fine scales and modeled at broader scales for other systems and ecological contexts, with examples in food web dynamics (Sanders et al 2014), demographic rates (de la Cruz et al 2008), and competition (Raventós et al 2010). Additionally, changes in spatial patterns of self-organized organisms may indicate impending ecosystems transitions such as desertification in terrestrial ecosystems (Dakos et al 2011) and degradation of intertidal diatom patches (Weerman et al 2012).…”

Soil fauna: key to new carbon models

“…Similar attempts to connect animal activity to carbon cycling have occurred in the past (e.g. Lavelle and Martin, 1992;Lavelle et al, 1998;Lavelle and Spain, 2006;Osler and Sommerkorn, 2007;Brussaard et al, 2007;Sanders et al, 2014), without any further change in the structure of carbon models. This was partly due to a lack of communication between modellers and experimenters, but also because the magnitude of animal effects on SOM dynamics remains poorly quantified (Schmitz et al, 2014).…”

“…faecal pellets, ant and termite mounds). Mounds and burrows are obvious signs of physical heterogeneity created by ecosystem engineers (Meysmann et al, 2006;Wilkinson et al, 2009;Sanders et al, 2014). These structures significantly affect microorganisms and plants (Chauvel et al, 1999;Frelich et al, 2006) and associated soil properties such as aggregate stability (Bossuyt et al, 2005(Bossuyt et al, , 2006 and hydraulic properties (Bottinelli et al, 2015;Andriuzzi et al, 2015).…”

“…Therefore, it is opportune to include approaches that have been developed during the past decades (Filser, 2002;Jiménez and Lal, 2006;Osler and Sommerkorn, 2007;Brussaard et al, 2007;Meysmann et al, 2006;Wall et al, 2008;Sanders et al, 2014). For instance, Lavelle et al (2004) implemented earthworm activity in the CENTURY model.…”

How habitat-modifying organisms structure the food web of two coastal ecosystems

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