The effect of cultivation and erosion on the nitrogen and carbon of some Kansas soils
1939
Hide, J.C. | Metzger, W.H.
At each of 20 sites in the eastern half of Kansas soil samples were taken to represent sod land, land which has been cultivated across the slope, and land which has been cultivated up and down the slope. Organic carbon and total nitrogen determinations were made on these samples. In comparison with the sod sample, cultivation across the slope associated with cropping has brought about a highly significant loss of carbon and nitrogen amounting to 37 and 32%, respectively, for the surface 7 inches of soil, and 25 and 20% in the 7- to 20-inch layer. The actual loss of carbon becomes significantly greater as the average annual rainfall decreases from 40 inches in southeast Kansas to 25 inches in north central Kansas. The carbon loss which occurred from the surface soil where the land has been cultivated across the slope is 16.8% less than where cultivation has been up and down the slope. This saving is statistically significant. If only that half of the data from the relatively humid extreme eastern section of the state is considered, the carbon loss was reduced 31.5% by cultivation across the slope.
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