We studied the spatial variation and correlation between gravimetrically measured soil surface moisture and surface temperature measured by thermocouple sensors (point measurements) and an infrared thermometer (area measurements). All measurements were taken on regular intervals along an 80-m transect on a bare soil. Both temperature and moisture exhibited cyclic behavior, which was attributed to possible differential soil compaction. The coefficient of variation for thermocouple temperatures was 54% smaller than that for infrared measurements. However, the means for both types of soil temperature measurements were not significantly different. In addition, based on semivariogram and autocorrelation analyses, the extent of spatial variability was similar for both types of temperature observations. The extent of spatial structure for soil moisture was less than that found for soil temperature. As a result, higher correlation coefficients between measured and kriged values (jackknifing procedure) were obtained for soil surface temperature (>0.83) than for surface soil moisture (>0.69). We also found that removing the observed cyclic patterns from the original data drastically reduced the spatial variations of soil moisture, as well as temperature observations.
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