Surface Soil Degradation and Soil Productivity Restoration and Maintenance

Abstract

In the Piedmont of the Southern Appalachian region, soil degradation is most often expressed by crop water deficit that limits crop yield in the warm season. To evaluate the nature of variability on these cropped lands, soybean [Glycine max (L.) Merr.] yield and associated soil characteristics were measured across the range of surface soil conditions in 40 farm fields. Factor analysis of the data permitted identification of variables responsible for most of the yield variability. Carbon in the surface soil was identified as the manageable soil variable that could significantly influence crop water availability and curtail soil erosion. Subsequently, selected crop cultures that supplied a range in quality and quantity of crop biomass to the soil surface were applied on three soil erosion classes for 5 yr. Large increases in rainfall infiltration and reduced soil erodibility were associated with no‐till planting of grain sorghum [Sorghum bicolor (L.) Moench] into crimson clover (Trifolium incarnatum L. ‘Tibbee’) in comparison to conventional tillage of grain sorghum and soybean. The maintenance of a decomposing mulch by crop residue additions of about 12 Mg ha−1 yr−1 generated high soil C levels in the 0‐ to 15‐mm depth and a high water stability of aggregates in the 0‐ to 80‐mm depth in comparison to incorporated crop residues. In the 6th yr, grain yield of conventionally tilled soybean was 30 to 100% greater on the previously no‐till crop culture than on the conventionally tilled. The restoration and maintenance of soil productivity commensurate with inherent site resources was associated with maintenance of a decomposing mulch on the soil surface derived from an appropriate quantity and quality of crop residue produced in situ.

Tillage intensity effects on chemical indicators of soil quality in two coastal plain soils

“…Although the amount of SOC accumulated within the first few cm may not represent substantive values quantitatively when compared to total C in the soil profile, it plays an important role in soil quality. Bruce et al (25) found that maintenance of SOC within the first few cm of soil is essential for improving infiltration and crop-available soil water on degraded Ultisols. An increase in SOC with no-tillage compared to other systems has been associated with greater return of crop residues (8), and/or lower soil organic matter decomposition (13).…”

Influência de sistemas de preparo do solo na produtividade da mandioca (Manihot esculenta, Crantz)

“…Por outro lado, nas camadas de 0,10-0,20 m e 0,20-0,30 m, nos dois anos agrícolas avaliados, não foram constatadas diferenças significativas entre os sistemas de preparo de solo. Resultados semelhantes foram obtidos por Tormena et al (1998) Bruce et al (1995), com apenas um revolvimento do solo pode-se perder a maior parte do incremento de matéria orgânica obtido com sistemas sem revolvimento do solo. Na superfície,…”

Distribution of Structural Carbohydrates in Corn Plants Across the Southeastern USA

“…A long-term study could reveal significant variations in the chemistry of corn stover tissue as a result of residue management practices and impacts to soil properties. Additionally, despite the limited effect of rye on stover composition, the benefits on soil productivity of cover crops under conservation tillage practices should always be considered [29,30]. Furthermore, retention of rye in the field could reduce soil contamination on feedstock and cause microclimate interaction that affect water retention properties and soil heating properties in the spring.…”