TY - GEN
T1 - Emerging mechanisms of ecosystem functioning in a warmer and drier world
AU - Grünzweig, José M.
AU - De Boeck, Hans J.
AU - Rey, Ana
AU - Tzuk, Omer
AU - Meron, Ehud
AU - Flores, Omar
AU - Santos, Maria J.
AU - Bahn, Michael
PY - 2020/5
Y1 - 2020/5
N2 - Ecosystems are expected to face a significantly warmer and drier climate
in the coming decades. Experiments have tried to unravel drought
responses of ecosystems in mesic and humid biomes, but the structure and
functioning of these systems may change when climatic regime shifts
occur. Here, we summarize major mechanisms typical of drylands and
indicate how these may come into play when current mesic ecosystems face
tipping points in a warmer and drier world.These dryland mechanisms of
ecosystem functioning encompass (i) processes of vegetation development,
such as self-organization of vegetation patchiness and formation of
biological soil crust, (ii) biologically driven biogeochemical and
physiological processes, such as drying-wetting cycles and hydraulic
redistribution, and (iii) abiotically driven biogeochemical processes,
such as photochemical degradation of organic matter and soil
hydrophobicity. We present insights from published studies and original
model simulations and mapping, and formulate hypotheses on thresholds
and spatial locations beyond which dryland mechanisms are expected to
operate in non-xeric ecosystems. Notably, for dryland mechanisms to get
activated elsewhere there is no need for non-xeric biomes to become
actual drylands. With a globally increasing area exposed to gradually
rising temperatures, moderate decline in precipitation, and increasing
frequency, duration and intensity of extreme heat and drought events, we
envision that dryland mechanisms will increasingly control ecosystem
functioning in many regions of the world.
AB - Ecosystems are expected to face a significantly warmer and drier climate
in the coming decades. Experiments have tried to unravel drought
responses of ecosystems in mesic and humid biomes, but the structure and
functioning of these systems may change when climatic regime shifts
occur. Here, we summarize major mechanisms typical of drylands and
indicate how these may come into play when current mesic ecosystems face
tipping points in a warmer and drier world.These dryland mechanisms of
ecosystem functioning encompass (i) processes of vegetation development,
such as self-organization of vegetation patchiness and formation of
biological soil crust, (ii) biologically driven biogeochemical and
physiological processes, such as drying-wetting cycles and hydraulic
redistribution, and (iii) abiotically driven biogeochemical processes,
such as photochemical degradation of organic matter and soil
hydrophobicity. We present insights from published studies and original
model simulations and mapping, and formulate hypotheses on thresholds
and spatial locations beyond which dryland mechanisms are expected to
operate in non-xeric ecosystems. Notably, for dryland mechanisms to get
activated elsewhere there is no need for non-xeric biomes to become
actual drylands. With a globally increasing area exposed to gradually
rising temperatures, moderate decline in precipitation, and increasing
frequency, duration and intensity of extreme heat and drought events, we
envision that dryland mechanisms will increasingly control ecosystem
functioning in many regions of the world.
U2 - 10.5194/egusphere-egu2020-13465
DO - 10.5194/egusphere-egu2020-13465
M3 - Conference contribution
VL - 22
SP - 13465
BT - 22nd EGU General Assembly, held online 4-8 May, 2020
ER -