Author
 |
Stott, Diane |
|
Submitted to: International Soil Science Society Conference Proceedings
Publication Type: Abstract Only Publication Acceptance Date: 3/31/1998 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: With progressive degradation of agricultural soils, monitoring changes in soil microbial and biochemical characteristics provides info on soil quality changes. This helps determine management practices to use to prevent further degradation and overcome specific site problems. A field study was conducted to determine the influence of soil microbiological and biochemical characteristics on infiltration rates. The study nine paired sites in IN and IL (USA), compared long-term no-till sites to ones that had remained under conventional management systems. A variety of soil microbial, biochemical, and physical characteristics were measured, including: organic C and N, dissolved organic C (DOC), soil carbohydrates, arylsulfatase, FDA hydrolysis, bulk density, soil penetrability, aggregate stability against slaking, and infiltration rate. Slaking was greater on the tilled sites. Infiltration rates were usually greater in the no-till system. On soils where there were some drainage problems, tillage systems employing moderate intensities, such as those using a chisel plow, actually had the higher infiltration rates. As tillage intensity increased, organic C and N decreased, as did the DOC, carbohydrate content, and enzymatic activities. The soil organic matter (SOM) was fractionated using several techniques. When divided into humics and fulvics, the SOM was analyzed for the presence of certain functional groups. The no-till sites tended to be richer in carboxyls. When fractionated using a density gradient, the no-till sites were richer in particulate organic matter. Using a standard scoring function, soil biochemical characteristics were used to rate the soil quality of the sites with respect to crusting and potential erosion. |
