Soil temperature change and its regional differences under different vegetation regions across China

Abstract

Changes in soil temperature will exert an important influence on the management and utilization of vegetation and agricultural production, whereas the spatiotemporal variations in soil temperature under different vegetation regions across China remain largely unknown. The shallow soil temperatures (0-20 cm) during the growing season (May-September) from 1965 to 2014 across China were analysed, and the findings showed that the spatial distribution of shallow soil temperature was determined primarily by latitude in eastern China (east of 110 E), and by altitude in western China (west of 110 E) with some high (low) temperature centres. The vegetation regions with relatively low soil temperatures are mainly concentrated in high altitude and high latitude areas, which have relatively large differences in soil temperature at different depths and relatively high soil warming rates. Over the past 50 years, shallow soil temperatures increased greatly during the growing season at the site, vegetation region and nation scales, but the warming rate and its relationship with climate change varied greatly. The soil temperature variables were affected substantially by air temperature and precipitation in the subtropical forest and tropical forest regions but were affected primarily by air temperature in the other vegetation regions. This difference may be due to the spatial difference in precipitation amounts across China, which affected the soil temperature via soil moisture feedback. Further study indicated that the warming rate in shallow soil was higher in stations (vegetation regions) with less precipitation than in those with more precipitation.

Three-Dimensional Dynamic Variations of Ground/Air Surface Temperatures and Their Correlation with Large-Scale Circulation Indexes in Southwest China (1980–2019)

“…This discrepancy might be attributable to the different numbers of stations used and the different lengths of study period. The annual averaged SATx, SATm, and SATn exhibit a climate jump in 1997, as confirmed in Wang et al [8]. However, the climate jump of GST (except GSTx) lags the climate jump of SAT, which might reflect a difference between the sensitivity of GST and SAT to climate change.…”

“…In such interactions, although soil temperature is different from air temperature in terms of value, oscillation [5], and variation trend [6], the two parameters are normally closely coupled. Previous research has investigated both the fluctuation of soil temperature at different depths [3,[7][8][9][10] and the relationship between soil temperature and air temperature [11][12][13][14]. However, this study focused on soil temperature measured at a depth of 0 cm, i.e., ground soil temperature (GST), and surface air temperature (SAT) because the difference between GST and SAT (i.e., SATD) is proportional to the surface sensible heat flux [15,16], which has substantial influence on soil microorganisms [17], vegetation [18], and climate [14,19].…”

The Role of Soil Temperature Feedbacks for Summer Air Temperature Variability Under Climate Change Over East Asia

“…It shows that the soil temperature changes in both mean state and interannual variability have relatively consistent patterns and magnitude (Figures 1e and 1f) to that in the surface air temperature (see Figure S6), which highlights the tight coupling between soil temperature and air temperature. This tight relationship between soil temperature and surface air temperature has been analyzed and proved in previous researches (Qian et al, 2011;Wang et al, 2021;Zhang et al, 2001;Zhu et al, 2018).…”

Effects of heat waves on soil temperatures in Slovenia

“…Changes in soil temperature affect many agricultural practices, so we wanted to examine changes during heat waves. The similar number of heat waves at 3 sites (except Ljubljana as an urban heat island) over the 25-year period confirms that the thresholds are appropriately set because in different climates all living organisms are acclimated to their usual conditions, so the threshold may not be the same everywhere (Wang et al, 2020). Air temperatures are strongly correlated with upper soil temperatures, and in Slovenia warming was observed at all depths in all seasons, but the threshold of 45°C was not (yet) reached at any depth (Pogačar et al, 2018).…”