How do Soil Moisture and Vegetation Covers Influence Soil Temperature in Drylands of Mediterranean Regions?

Abstract

Interactions between land and atmosphere directly influence hydrometeorological processes and, therefore, the local climate. However, because of heterogeneity of vegetation covers these feedbacks can change over small areas, becoming more complex. This study aims to define how the interactions between soil moisture and vegetation covers influence soil temperatures in very water-limited environments. In order to do that, soil water content and soil temperature were continuously monitored with a frequency of 30 min over two and half hydrological years, using capacitance and temperature sensors that were located in open grasslands and below tree canopies. The study was carried out on three study areas located in drylands of Mediterranean climate. Results highlighted the importance of soil moisture and vegetation cover in modifying soil temperatures. During daytime and with low soil moisture conditions, daily maximum soil temperatures were, on average, 7.1 °C lower below tree canopies than in the air, whereas they were 4.2 °C higher in grasslands than in the air. As soil wetness decreased, soil temperature increased, although this effect was significantly weaker below tree canopies than in grasslands. Both high soil water content and the effect of shading were reflected in a decrease of maximum soil temperatures and of their daily amplitudes. Statistical analysis emphasized the influence of soil temperature on soil water reduction, regardless of vegetation cover. If soil moisture deficits become more frequent due to climate change, variations in soil temperature could increase, affecting hydrometeorological processes and local climate.

Dryland Cropping Systems, Weed Communities, and Disease Status Modulate the Effect of Climate Conditions on Wheat Soil Bacterial Communities

“…This may reflect the more complex interaction between plants, microorganisms, and soil conditions, as soil mois- ture can somewhat stabilize soil temperature (53). Plant foliation, which increases with air temperature, in turn shades soil and can buffer further increases in soil temperature (53), thus better supporting microbial communities. Cropping systems are known to be associated with particular soil microbial communities (23,45,54).…”

Soil Hydrology for a Sustainable Land Management: Theory and Practice

“…This Special Issue collects 12 original contributions focused on soil hydrology and aimed to address the challenging topic of sustainable land management. From a methodological point of view, the contributions involve both field [8][9][10][11]13,19] and laboratory [14,15] experiments, and modelling [6,[16][17][18] studies. The Special Issue includes studies carried out at different spatial scales, from the field-to regional-scales.…”

“…The Special Issue includes studies carried out at different spatial scales, from the field-to regional-scales. A wide range of geographic regions are also covered, including Brazil [11,13], Mexico [16], Mediterranean basin [6,8,10,14,18], and Central [15,17,19] and Western [9] Europe. Specifically, contributions focus on five main topics including (i) land-use change [8,12,18,19], (ii) water use efficiency [14], (iii) erosion risk [6,17], (iv) solute transport [15], and (v) new methods and devices for improved characterization of soil physical and hydraulic properties [9][10][11]16].…”

“…Lozano-Parra et al [18] investigated the effect of the interactions between soil moisture and vegetation covers on soil temperature. These authors monitored for two and a half hydrological years of soil water content and soil temperature of open grasslands and below tree canopies.…”

“…Contributions of this SI were focused on: BEST-procedure [7] application, for a simple and expeditious method for estimating hydraulic properties of the soil [8][9][10][11]; Steady version of the Simplified method based on a Beerkan Infiltration run (SSBI method) [12] for field saturated hydraulic conductivity (K s ) estimation [13]; Hydrus-1D and SWAP codes for modelling soil water dynamics [11,14,15]; a new low-cost device for the automation of K s measurements in the laboratory [16]. Also, investigations on the topic of rainfall erosivity [6,17], or the impact of land-vegetation cover interaction on soil water content [18] and soil water repellency [19], increased our knowledge on the sustainable management of specific agro-environments. A synthesis of main results and/or innovative methods to assess those changes from a soil hydrology point of view were reported in the following section.…”