Relationship between screen Temperature and soil temperature in different soil moisture levels (case study: Zerghan in Fars province)

Air temperature is one of the most important atmospheric parameters in energy supply of plants in different phonological stages. So soil temperature is significant chemical reactions of and soil nutrients translocation from root to growing and reproducting organ and consequently it results in more and better crop. In Meteorological Organization, air temperature continually measure and register in atmospheric, Synoptic and Climate Stations and in addition to experts read the parameters, register machines also register all the day long changing process on special papers. But soil depths temperature reads and takes note by observers in special times of morning, noon and evening in synoptic stations. The research goal was evaluating surface soil depth temperature in according to observing air temperature and soil moisture. To reach this goal, statistics about air temperature and soil moisture, 5 & 15 cm depth temperature and moisture are registered in 5 months period (March to July 2006). Statistics analysis was based on statistics standard methods and used Excel, Statgraph and SPSS software.