Soil Property Trends: A Time-Series Basis for Soil Quality

MICHAEL J. SINGER1*, FABRICE DECLERCK,1 AND PETER LINDERT2

1Department of Land, Air, and Water Resources
2Agricultural History Center
Davis Campus

Summary

Some progress was made in our goal of creating an electronic database of geographical information from selected soil surveys. However, after investing heavily in time and personnel with too little progress, digitizing was abandoned, and we continued database preparation by hand. Over 130 archival soil samples dating from the 1940s through the 1970s were obtained for analysis of key soil properties. Sample locations were determined accurately, and arrangements currently are being made to resample soils at these locations. Landowner information is being sought from county assessor offices, and permission is being obtained from present landowners to enter properties and resample locations represented by the archival samples. Additional data from soil survey reports is being developed to supplement the data from the original five sampling counties in California (Colusa, Fresno, Imperial, San Bernadino, and San Joaquín).