Spatial distribution of near surface temperature under bare and vegetated plots

The soil surface temperature plays a crucial role in hydrological modeling and land-atmosphere energy balance by controlling the amount of evaporation and thermal heat exchange between the land surface and overlying atmosphere. This energy exchange in turn plays a vital role in modifying atmospheric dynamics, including small-scale phenomena such as thunderstorms as well as larger-scale events such as droughts and floods. Understanding the relationships between the soil temperature distribution in the profile with properties such as surface moisture, radiation balance, and evaporation is important in order to forecast hydrological and meteorological processes. The research was conducted at Alabama A&M University, Winfred Thomas Agricultural Experiment Station located near Hazel Green, Alabama. In 1998, the study was conducted on six plots composed of two 50×60 m and four 30×50 m plots, one bare, one grass and four corn plots having four different vegetation density. Measurements were made within each plot on two locations and at three different positions within each location. The total area of sampling was 25m². Soil surface temperature was measured using infrared thermometer and profile soil temperature was measured using a temperature probe. Results showed that mean soil temperature for each depth averaged over all plots indicated significant difference (p=0.05) for measurements taken during morning and afternoon. However, measurements taken within each plot did not indicate significant difference by location and position averaged over depth. The results have implications for remote sensing