Nonlinear effects of consumer density on multiple ecosystem processes
Abstract
Summary1. In the face of human‐induced declines in the abundance of common species, ecologists have become interested in quantifying how changes in density affect rates of biophysical processes, hence ecosystem function. We manipulated the density of a dominant detritivore (the cased caddisfly, Limnephilus externus) in subalpine ponds to measure effects on the release of detritus‐bound nutrients and energy.2. Detritus decay rates (k, mass loss) increased threefold, and the loss of nitrogen (N) and phosphorus (P) from detrital substrates doubled across a range of historically observed caddisfly densities. Ammonium and total soluble phosphorus concentrations in the water column also increased with caddisfly density on some dates. Decay rates, nutrient release and the change in total detritivore biomass all exhibited threshold or declining responses at the highest densities.3. We attributed these threshold responses in biophysical processes to intraspecific competition for limiting resources manifested at the population level, as density‐dependent per‐capita consumption, growth, development and case : body size in caddisflies was observed. Moreover, caddisflies increasingly grazed on algae at high densities, presumably in response to limiting detrital resources.4. These results provide evidence that changes in population size of a common species will have nonlinear, threshold effects on the rates of biophysical processes at the ecosystem level. Given the ubiquity of negative density dependence in nature, nonlinear consumer density–ecosystem function relationships should be common across species and ecosystems.
Local Knowledge Graph (25 entities)
Related Works
Items connected by shared entities, co-authorship, citations, or semantic similarity.
Consequences of climate-induced range expansions on multiple ecosystem functions
Species-specific traits predict whole-assemblage detritus processing by pond invertebrates
Role of animal detritivores in the breakdown of emergent plant detrius in temporary ponds
Data from: Short-term, low-level nitrogen deposition dampens a trophic cascade between bears and plants
Facilitation strength across environmental and beneficiary trait gradients in stream communities
Data from: Biotic and abiotic variables influencing plant litter breakdown in streams: a global study
Effect of Keystone Mine Effluent on Colonization of Stream Benthos
Beaver Pond Ecosystems and Their Relationships to Multi-Use Natural Resource Management
A New Hydrologic Perspective of How Beaver Ponds Function
Cited By (47 times, 19 in Knowledge Hub)
Comparing decomposition rates and detritivore preferences for caddisfly (Trichoptera) cases versus ambient detritus
Consequences of climate-induced range expansions on multiple ecosystem functions
Effects of a caddisfly range shift on competition and facilitation in high elevation ponds
Limnephilus externus Case Grazing
Species-specific traits predict whole-assemblage detritus processing by pond invertebrates
Predators balance consequences of climate-change-induced habitat shifts for range-shifting and resident species
Testing for competition, facilitation, and intraguild predation between two co-dominant detritivores: the caddisfly <i> Limnephilus externus </i> and chironomid midges
From animals to ecosystem processes: Predicting functional outcomes of climate-driven changes in animal communities through species traits
Biotic interactions at species’ range limits in a changing climate
Characterizing the role of phosphorus availability and periphytic algae in the food choice and performance of detritivorous caddisflies (Trichoptera:Limnephilidae)
Elevation alters outcome of competition between resident and range shifting species
Ecological role of <i>Limnephilus abbreviates</i> in detritus dynamics
High interspecific variation in nutrient excretion within a guild of closely related caddisfly species
Role of animal detritivores in the breakdown of emergent plant detrius in temporary ponds
Determining the Effects of Climate-Induced Range Shifts on Caddisfly Population Dynamics
Pond nutrient storage across permanence and temporal gradients
Caddisfly behavioral responses to drying cues in temporary ponds: Implications for effects of climate change
Testing for nutrient limitation of algal biomass across elevational and permanence gradients in high elevation ponds near the Rocky Mountain Biological Lab
Herbivore growth responses to nutrient mobilization by detritivores
References (71)
7 in Knowledge Hub, 64 external