Organic matter production as inferred from corn (zea mays l.) yield
1973
LEEPER, R. A.
It is proposed that present-day crop yields can be used in conjunction with soil organic matter content in inferring the amount of organic matter that was produced during the latest stage of soil development. Two soil sequences were studied in which corn yields from small plots within one field were significantly correlated with the amount of plant-available stored soil moisture. The moisture differential was obtained by locating plots according to different depths to a root-restricting natric horizon or dense, calcareous glacial till. The yield increase for an additional centimeter of rooting depth varied considerably over the three years and four locations due to weather variation.A literature review revealed that soil production differences similar to those of the corn plots also occurred under native conditions and in long-term corn yields. Modern crop yields must be used in cases where production under native vegetation and long-term crop yields are not available even though soil organic matter content may be influenced by factors other than just organic matter production.
显示更多 [+] 显示较少 [-]