Global patterns in lake ecosystem responses to warming based on the temperature dependence of metabolism

Abstract

Climate warming is expected to have large effects on ecosystems in part due to the temperature dependence of metabolism. The responses of metabolic rates to climate warming may be greatest in the tropics and at low elevations because mean temperatures are warmer there and metabolic rates respond exponentially to temperature (with exponents >1). However, if warming rates are sufficiently fast in higher latitude/elevation lakes, metabolic rate responses to warming may still be greater there even though metabolic rates respond exponentially to temperature. Thus, a wide range of global patterns in the magnitude of metabolic rate responses to warming could emerge depending on global patterns of temperature and warming rates. Here we use the Boltzmann-Arrhenius equation, published estimates of activation energy, and time series of temperature from 271 lakes to estimate long-term (1970-2010) changes in 64 metabolic processes in lakes. The estimated responses of metabolic processes to warming were usually greatest in tropical/low-elevation lakes even though surface temperatures in higher latitude/elevation lakes are warming faster. However, when the thermal sensitivity of a metabolic process is especially weak, higher latitude/elevation lakes had larger responses to warming in parallel with warming rates. Our results show that the sensitivity of a given response to temperature (as described by its activation energy) provides a simple heuristic for predicting whether tropical/low-elevation lakes will have larger or smaller metabolic responses to warming than higher latitude/elevation lakes. Overall, we conclude that the direct metabolic consequences of lake warming are likely to be felt most strongly at low latitudes and low elevations where metabolism-linked ecosystem services may be most affected.

Effects of trophic status, water level, and temperature on shallow lake metabolism and metabolic balance: A standardized pan‐European mesocosm experiment

“…Potential mechanisms behind this variation include acclimatization and adaptation processes, which are hypothesized to induce reduced temperature sensitivity with increasing average temperature (Atkin and Tjoelker ; Hikosaka et al ; Hartley et al ; Angilletta ; Smith and Dukes ). In this study, we found no evidence for a systematic change in activation energy with average temperature (Supporting Information S4 Table 2), which is in line with Perkins et al (), who reported consistent Q10 temperature coefficient values for ER regardless of the thermal history or community composition of biofilms, as well as with a global survey of activation energies based on satellite data by Kraemer et al ().…”

Transparency, Geomorphology and Mixing Regime Explain Variability in Trends in Lake Temperature and Stratification across Northeastern North America (1975–2014)

“…Oxygen, lake temperature and water transparency also regulate predator-prey interactions through the vertical distribution and migration of phytoplankton and zooplankton and thereby modify the availability of refugia from predation (e.g., [90][91][92]). Further, a compressed or non-existent hypolimnion, due to a deeper thermocline and increasingly hypoxic conditions, will have costly energetic consequences for cooland cold-water fishes [93]. However, the opposite pattern could emerge in lakes with increasing hypolimnetic volume, assuming ample deepwater oxygen concentrations.…”

Cross‐Scale Interactions Dictate Regional Lake Carbon Flux and Productivity Response to Future Climate

“…Climate change has already impacted lakes and reservoirs in heterogeneous ways (McCullough et al, ) as cross‐scale interactions (Soranno et al, ) between climate and lake‐specific characteristics have caused some lake water temperatures to increase faster than air temperature and other lake water temperatures to cool despite increased air temperature (O'Reilly et al, ; Rose et al, ). These lake‐specific changes in water temperature impact organismal metabolic rates, with heterotrophy more sensitive to changes in temperature than autotrophy (Kraemer et al, ; Yvon‐Durocher et al, ). Watershed inputs of C and nutrients are also likely to change with predicted changes in precipitation.…”