10cm Soil Temperature Data Validation and Model In the Transylvanian Plain, Romania.

The Transylvanian Plain (TP), Romania, is a geographic region located in north-central Romania; the terrain is composed rolling hills with tree covered summits and is surrounded by the Carpathian mountains to the East and South and the Apuseni mountains to the West. The Somes and Mures are two major rivers that border the TP to the North and South, respectively. The TP is an agronomic area of importance in Romania for corn, sugar beet, potato, sunflower, and soybean. Soil temperature is known to be controlled by several different factors in the environment. Some of these include: elevation, slope, texture, aspect, latitude, and distance from a water body. This study is interested in how well these factors influence a monthly averaged 10 cm soil temperature model in the TP. A factor analysis was run on sites and months for 10 cm moisture and temperature at the 20 stations for 15 months ranging from 2009-2010.  The factor results were interpolated using a spline method to look at similarities between the factors.  The significance of the aforementioned variables was also evaluated using backward selection in SAS 9.2. The significant variables were then evaluated in ArcGIS to create a model and produce a 10 cm soil temperature map. Soil temperature regimes are known to be Mesic in the TP; based on 2008 and 2009, 50 cm temperature data, with a mean of 10.98 ^oC for 10 stations. Pedon descriptions have been made at each site location with subsequent taxonomic classification in both U.S. Soil Taxonomy and Romanian Soil Classification. Soils have mostly been Mollisols (Cernosoluri), and to a lesser extent, Alfisols (Luvisoluri), Inceptisols (Cambisoluri), and Entisols (Protisoluri).