Precipitation–productivity relationships and the duration of precipitation anomalies: An underappreciated dimension of climate change

Abstract

In terrestrial ecosystems, climate change forecasts of increased frequencies and magnitudes of wet and dry precipitation anomalies are expected to shift precipitation–net primary productivity (PPT–NPP) relationships from linear to nonlinear. Less understood, however, is how future changes in the duration of PPT anomalies will alter PPT–NPP relationships. A review of the literature shows strong potential for the duration of wet and dry PPT anomalies to impact NPP and to interact with the magnitude of anomalies. Within semi‐arid and mesic grassland ecosystems, PPT gradient experiments indicate that short‐duration (1 year) PPT anomalies are often insufficient to drive nonlinear aboveground NPP responses. But long‐term studies, within desert to forest ecosystems, demonstrate how multi‐year PPT anomalies may result in increasing impacts on NPP through time, and thus alter PPT–NPP relationships. We present a conceptual model detailing how NPP responses to PPT anomalies may amplify with the duration of an event, how responses may vary in xeric vs. mesic ecosystems, and how these differences are most likely due to demographic mechanisms. Experiments that can unravel the independent and interactive impacts of the magnitude and duration of wet and dry PPT anomalies are needed, with multi‐site long‐term PPT gradient experiments particularly well‐suited for this task.

Biotic vs abiotic controls on temporal sensitivity of primary production to precipitation across North American drylands

“…Research on NPP–PPT relationships is often motivated by the expectation that better understanding will increase our capacity to anticipate the ecosystem impacts of future changes in PPT regimes (Estiarte et al ., 2016; Knapp et al ., 2017; Felton et al ., 2021). Drylands are thought to be especially vulnerable to projected increases in PPT variability and extremes (Maurer et al ., 2020).…”

Divergent responses of primary production to increasing precipitation variability in global drylands

“…In addition to MAP, the effect of precipitation variability on ANPP may be also modulated by MAT, soil type, vegetation type, as well as the variability patterns (i.e., magnitude, duration, and stochasticity) and antecedent effects of precipitation (Felton et al, 2021;Liu et al, 2020;Rudgers et al, 2018;Sala et al, 2012).…”

Biodiversity conservation in climate change driven transient communities

“…Models predict that precipitation regimes will change due to climatic warming (IPCC 2014(IPCC , 2019. Decreases and increases in rainfall amount and frequency are expected in large parts of the world and recent studies suggest that the intensity of rainfall events is also changing (Felton et al 2020;Myhre 2019). The anticipated magnitude of precipitation change varies between climate change scenarios.…”

“…Precipitation is the other important factor determining species distribution (Illan et al 2014). Especially plant species will be sensitive to changes in precipitation because the water uptake and transpiration determine their growth rate (Felton et al 2020;Schippers et al 2015a;Wu et al 2011). In general, wetland species like amphibians will suffer from precipitation reduction (Griffiths et al 2010) whereas precipitation increase will stimulate the abundance of wetland species (Lawler et al 2009).…”

“…The increase of greenhouse gas concentrations caused by human activities enhances the absorption of radiation in the atmosphere leading to an elevation of air temperatures and changing precipitation patterns (Suggitt 2017;Felton et al 2020). The land surface has warmed on average by 1.53 °C (1.38-1.68 °C) over approximately the last 120 years, with an acute warming observed from 1980 onwards (IPCC 2019).…”