Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 6/24/1999
Publication Date: N/A
Technical Abstract: Animal traffic on pastures could potentially destroy the integrity of soil surface aggregation, thereby causing excessive water runoff and soil erosion. We sampled soil under pasture, crop, and forest to depths of 0-5, 5-12.5, and 12.5-20 cm. Mean-weight diameter of water-stable aggregates (1) was 21% greater under 20-year-old tall fescue-common bermudagrass pasture than under 24-year-old conservation-tillage cropland, (2) was not different between 15- to 19-year-old grazed and hayed hybrid bermudagrass pastures, (3) was positively related to stand age of grass (i.e., from 6 to 50 years), and (4) was 21 to 46% greater under long-term grazed or hayed pasture than nearby forestland or conservation-tillage cropland. Total glomalin was unaffected by management, perhaps because we only investigated systems with relatively high macroaggregation. Our results indicate that grazed pasture management systems in the Southern Piedmont USA have equal or greater soil aggregate distribution than land without grazing animals, including hayland, conservation-tillage cropland, and forestland.