ters to characterize both agricultural and rangeland A DYNAMIC CONE PENETROMETER soils, however, has been limited by concerns about (i) FOR MEASURING SOIL instrument cost, (ii) measurement repeatability, (iii) limited ranges of soil resistance that can be measured by PENETRATION RESISTANCE a single penetrometer, and (iv) difficulties in comparing Jeffrey E. Herrick* and Tim L. Jones data collec...

The abundance and diversity of archaeal assemblages were analyzed in soils collected from Gyorae Gotjawal forest, Jeju, Korea. Gotjawal soil refers to soil derived from a lava-formed forest, characterized by high organic matter content, fertility, and poor rocky soil. Using domain-specific primers, archaeal 16S rRNA gene sequences were PCR amplified for clone library construction, and a total o...

Abstract Replacement of bare fallow in rotations by cover crops is a promising tool to reduce crusting, although the interactions with soil moisture and effect crop species are still not well understood. The objective this work was determine how modify surface response penetration their relation water content. Two winter crops, barley (Hordeum vulgare L.) vetch (Vicia sp. L.), were compared tre...

Information on the influence of impregnation of cementitious slurry at the soil-structure interface of bored cast in-situ foundation is inadequate in available literatures. Moreover, influence of such impregnation on negating the detrimental effects of smear zone, formed by construction tools, surrounding the borehole is also unknown. In classical foundation engineering, influences of smear and...

Rate effects are examined in the steady pore pressure distribution induced as a result of penetration of standard and ball penetrometers. The incompressible flow field, which develops around the penetrometer is used to define the approximate soil velocity field local to the penetrometer tip. This prescribes the Lagrangian framework for the migration of the fluid saturated porous medium, definin...

this study was carried out to evaluate the effects of tillage practices (with different depths) on soil penetration resistance, technical parameters and grain yield of wheat crop. the experiment was conducted as a randomized complete block design with three replications for two years. treatments included: moldboard plow fallowed by two passes of disc harrow and leveler (ct), two passes of disc ...

The degree of compactness (D) has been de®ned earlier as the dry bulk density of a soil in percent of a reference bulk density obtained by a standardized uniaxial compression test on large samples at a stress of 200 kPa. It was primarily aimed for use in annually disturbed soil layers. Field experiments have demonstrated its usefulness for characterizing the state of compactness from a crop pro...