The influence of grazing upon certain soil and climatic conditions in farm woodlands
1940
Chandler, R.F. Jr
The results of a study of soil and climatic conditions in 18 paired grazed and ungrazed woodland areas can be summarized as follows: 1. No significant differences in pH of the surface soil were found. 2. The soil organic-matter content was higher under the ungrazed conditions, averaging 8.5% as compared with 6.4% for the grazed areas. 3. The volume weight of the grazed soils averaged 1.15, while the ungrazed soils averaged 0.92. 4. The moisture equivalent was higher under the ungrazed conditions and correlated well with soil organic matter content. 5. The moisture content of the soil was highest on the ungrazed areas, whether expressed as percentage of oven-dry soil or as relative wetness. 6. Air and surface soil temperatures were highest in the grazed woodland areas. 7. The amount of light penetrating the forest canopy was much greater in the grazed woodlots, averaging 21% of full sunlight as compared with only 3.03% under the ungrazed conditions. 8. The relative humidity of the air was highest under the ungrazed conditions, being 65.7% as compared with only 53.6% for the grazed woodlands.
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