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R. R. Shahin
Soil warming can increase nutrient uptake from 100 to 300% by enlarging the
root surface area and increasing rates of nutrient diffusion and water influx [114].
Temperature increases in the rhizosphere can also stimulate nutrient acquisition by
increasing nutrient uptake via faster ion diffusion rates and increased root metabolism
[115]. However, any positive effects of warmer temperature on nutrient capture are
dependent on adequate soil moisture. If under dry conditions higher temperatures
result in extreme vapor pressure deficits then nutrient acquisition driven by mass
flow will decrease [116]. In barley and wheat, the soil available K and Ca and their
uptake in grain were increased with soil warming (+2.5 °C), while the concentration
of Mg was slightly reduced [117, 118].
4.1.2 Poor Soil Water Regime
As climate changes, soil moisture levels will be influenced by direct climatic effects
(precipitation, temperature effects on evaporation), climate-induced changes in vegetation, different plant growth rates and different cycles, different rates of soil water
extraction and the effect of enhanced CO levels on plant transpiration. Changes
in soil water fluxes may also feedback to the climate itself and even contribute to
drought conditions by decreasing available moisture, altering circulation patterns and
increasing air temperatures [119]. “Increasing temperatures will also lead to greater
evapotranspiration and hence loss of water from the soil. Much will depend on land
use also, which itself will change, together with its water needs” [112].
The integral influence of climate-hydrology-vegetation-land use changes is
reflected by the field water balance and soil moisture regime. As for example, the
rise in temperature increases the potential evaporation and transpiration. Whereas
the decrease in atmospheric precipitation will result in a decrease in water infiltration (I) and water storage (S) in the soil and plants water supply; surface runoff (R),
consequently water erosion hazard (but increasing the risk of wind erosion for dry surfaces), filtration losses and groundwater recharge (G) and will increase evaporation
losses; the rate of transpiration (if the vegetation or crop canopy has not deteriorated
due to water deficiency), drought sensitivity with its physiological, ecological and
environmental consequences [120].
4.1.3 Shifting of Soil Microbiome
The rising temperatures would be expected to speed up the decomposition of labile
(easily degraded) soil organic compounds such as the carbohydrates from leaf litter, whereas more biochemically resistant carbon-containing structures—such as the
lignin from woody tissues and lipids from leaf cuticles—would be expected to remain
stable over decades, possibly even centuries. Global warming may change presentday decomposition patterns by altering the soil microbial communities and activities,
thus changing the overall flow of carbon into and out of the soil and affecting soil
fertility as well [112, 121].
R. R. Shahin
Soil warming can increase nutrient uptake from 100 to 300% by enlarging the
root surface area and increasing rates of nutrient diffusion and water influx [114].
Temperature increases in the rhizosphere can also stimulate nutrient acquisition by
increasing nutrient uptake via faster ion diffusion rates and increased root metabolism
[115]. However, any positive effects of warmer temperature on nutrient capture are
dependent on adequate soil moisture. If under dry conditions higher temperatures
result in extreme vapor pressure deficits then nutrient acquisition driven by mass
flow will decrease [116]. In barley and wheat, the soil available K and Ca and their
uptake in grain were increased with soil warming (+2.5 °C), while the concentration
of Mg was slightly reduced [117, 118].
4.1.2 Poor Soil Water Regime
As climate changes, soil moisture levels will be influenced by direct climatic effects
(precipitation, temperature effects on evaporation), climate-induced changes in vegetation, different plant growth rates and different cycles, different rates of soil water
extraction and the effect of enhanced CO levels on plant transpiration. Changes
in soil water fluxes may also feedback to the climate itself and even contribute to
drought conditions by decreasing available moisture, altering circulation patterns and
increasing air temperatures [119]. “Increasing temperatures will also lead to greater
evapotranspiration and hence loss of water from the soil. Much will depend on land
use also, which itself will change, together with its water needs” [112].
The integral influence of climate-hydrology-vegetation-land use changes is
reflected by the field water balance and soil moisture regime. As for example, the
rise in temperature increases the potential evaporation and transpiration. Whereas
the decrease in atmospheric precipitation will result in a decrease in water infiltration (I) and water storage (S) in the soil and plants water supply; surface runoff (R),
consequently water erosion hazard (but increasing the risk of wind erosion for dry surfaces), filtration losses and groundwater recharge (G) and will increase evaporation
losses; the rate of transpiration (if the vegetation or crop canopy has not deteriorated
due to water deficiency), drought sensitivity with its physiological, ecological and
environmental consequences [120].
4.1.3 Shifting of Soil Microbiome
The rising temperatures would be expected to speed up the decomposition of labile
(easily degraded) soil organic compounds such as the carbohydrates from leaf litter, whereas more biochemically resistant carbon-containing structures—such as the
lignin from woody tissues and lipids from leaf cuticles—would be expected to remain
stable over decades, possibly even centuries. Global warming may change presentday decomposition patterns by altering the soil microbial communities and activities,
thus changing the overall flow of carbon into and out of the soil and affecting soil
fertility as well [112, 121].