Patterns in the Fate of Production in Plant Communities

Abstract

I examine, through an extensive compilation of published reports, the nature and variability of carbon flow (i.e., primary production, herbivory, detrital production, decomposition, export, and biomass and detrital storage) in a range of aquatic and terrestrial plant communities. Communities composed of more nutritional plants (i.e., higher nutrient concentrations) lose higher percentages of production to herbivores, channel lower percentages as detritus, experience faster decomposition rates, and, as a result, store smaller carbon pools. These results suggest plant palatability as a main limiting factor of consumer metabolical and feeding rates across communities. Hence, across communities, plant nutritional quality may be regarded as a descriptor of the importance of herbivore control on plant biomass ("top-down" control), the rapidity of nutrient and energy recycling, and the magnitude of carbon storage. These results contribute to an understanding of how much and why the trophic routes of carbon flow, and their ecological implications, vary across plant communities. They also offer a basis to predict the effects of widespread enhancement of plant nutritional quality due to large-scale anthropogenic eutrophication on carbon balances in ecosystems.

The tropicalization of temperate marine ecosystems: climate-mediated changes in herbivory and community phase shifts

“…(c) Latitudinal-and temperature-mediated changes in nutritional quality of food sources Globally, carbon : nitrogen ratios of plants predict the proportion of primary production consumed by herbivores [60] and macrophytes with higher nitrogen concentrations are frequently preferred by tropical herbivores [45]. Nitrogen content of plants consistently increases with latitude [61], thus, nitrogen-rich, temperate macrophytes may enhance the fitness of tropical herbivores and exacerbate herbivore persistence and influence in temperate locations.…”

From Elements to Function: Toward Unifying Ecological Stoichiometry and Trait-Based Ecology

“…However, it is important to consider the intrinsic differences between producer-consumer interactions in aquatic and terrestrial ecosystems. While planktonic herbivores may eat a very large percentage (70-80%) of the daily primary production (Calbet, 2008;Löder et al, 2011), in terrestrial ecosystems, plants are less nutritional and lose lower percentages of production to herbivores, and a higher level of C is channeled as detritus (Cebrian, 1999). Traits directly influencing herbivore stoichiometry should therefore play only a small role in the cycling of nutrients in forested ecosystems, with decomposers and detritivores playing a more important role Loreau, 2009, 2013).…”

Contrasting mechanisms of dislodgement and erosion contribute to production of kelp detritus

“…In some cases, when grazers are abundant, kelps are among the primary producers most strongly affected by herbivory (Poore et al 2012). However, similar to many terrestrial ecosystems, it is often the case that only 10-15% of the production from kelp beds is consumed locally by herbivores, while 85-90% of the production is not directly consumed and becomes detritus (Cebrian 1999), which is frequently exported from the kelp beds to distant habitats where it is consumed (Vanderklift and Wernberg 2008). Consequently, kelp detritus subsidizes a large variety of habitats, including beaches, intertidal rocky shores, distant reefs, submarine canyons, seagrass beds, and small islands (Polis et al 1997;Krumhansl and Scheibling 2012).…”