Soil Carbon, Nitrogen, and Aggregation in Response to Type and Frequency of Tillage

Abstract

Little information exists on the biogeochemical effects of combining no‐tillage planting with paraplowing (to improve deep water penetration) or with secondary tillage (to control weeds). We determined surface residue and soil C and N pools (total, particulate, microbial biomass, and mineralizable) and water‐stable aggregation at depths of 0 to 25, 25 to 75, and 75 to 150 mm from a Cecil sandy loam (fine, kaolinitic, thermic Typic Kanhapludults) in Georgia. Soil tillage treatments were a factorial arrangement of tillage type [(i) minimal disturbance with in‐row chisel at planting, (ii) no‐tillage planting with autumn paraplow, and (iii) no‐tillage planting with secondary tillage during the summer] and tillage frequency [(i) every year, (ii) every second year, and (iii) every fourth year]. No‐tillage planting without further disturbance occurred in remaining years. At a depth of 0 to 25 mm, basal soil respiration averaged 9 mg kg‐1 d‐1 with conventional tillage, 27 mg kg‐1 d‐1 with no‐tillage planting and soil disturbance every year, and 36 mg kg‐1 d‐1 with no‐tillage planting and soil disturbance every fourth year. At a depth of 0 to 150 mm, mean‐weight diameter averaged 1.03 mm with conventional tillage, 1.12 mm with paraplow, 1.17 mm with secondary tillage, and 1.23 mm with in‐row chisel. No‐tillage planting with alternative tillage types and frequencies not only improved surface soil properties compared with conventional tillage, but also improved seed cotton yield an average of 19%. Biophysical improvement of surface soil structure would presumably lead to greater water infiltration and improved water use efficiency in the long term.

Physical, chemical and microbiological properties of an Andisol as related to land use and tillage practice

“…The highest amount of organic matter was observed under NT. Franzluebbers et al (1999) observed that the concentration of organic matter was higher in the surface soil under no-tillage systems. Less disruption resulted in greater accumulation of surface residue carbon.…”

Soil‐Test Biological Activity with the Flush of CO2: I. C and N Characteristics of Soils in Corn Production

“…Briefly, soil microbial biomass C was determined with chloroform fumigation-incubation without subtraction of a control and using an efficiency factor of 0.41 (Voroney and Paul, 1984;Franzluebbers et al, 1999). The flush of CO 2 following rewetting of dried soil (3 d) and cumulative C and N mineralization during 24 d of incubation were determined with aerobic incubation of soil at 50% water-filled pore space and 25°C.…”

Soil organic matter, biota and aggregation in temperate and tropical soils - Effects of no-tillage

“…9). This more pronounced aggregation increase does, however, not seem to lead to an [3,26,[30][31][32]35,38,59,65,77,79,109,111,113,114,139,164,172,173,177,194,Paustian and Elliott,unpublished,214,219,220,241] for (sub)tropical soils and from [2,11,22,42,50,[54][55][56]58,67,72,78,84,85,89,93,95,96,104,105,133,134,136,146,…”

“…Relative soil aggregation under no-tillage (NT) versus conventional tillage (CT), expressed as the ratio of the mean weight diameter of water-stable aggregates. Data from [35,57,59,60,106,111,132,137,164,188,216,228] for (sub)tropical soils and from [8,53,108,115,161,233,250,264] for temperate soils. Table VII.…”