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...

Soils release more carbon, primarily as carbon dioxide (CO2), per annum than current global anthropogenic emissions. Soils emit CO2 through mineralization and decomposition of organic matter and respiration of roots and soil organisms. Given this, the evaluation of the effects of abiotic factors onmicrobial activity is of major importance when considering the mitigation of greenhouse gases emis...

Dynamic compaction is a soil improvement method which has been widely used for the increase of bearing capacity through stress wave propagation during heavy tamping. The cost and time of project implementation can be effectively curtailed by developing a model that can be used in the design of dynamic compaction operations. The numerical models offered so far are mostly one or two-dimensional, ...

Seeds and young seedlings often encounter high soluble salt levels in the upmost soil layers, impeding vigorous growth by affecting root establishment. Computed tomography (CT) scanning used at low X-ray doses can help study root development in such conditions non-destructively, because plants are allowed to grow throughout the experiment. Using a high-resolution Toshiba XVision CT scanner, we ...

This study was to determine whether Arthrobotrys flagrans, A. oligospora, and Meria coniospora would control the root-knot nematode Meloidogyne hapla on alfalfa and tomato. Alfalfa seeds were coated with a fungus-rye powder in 2% cellulose and were planted in infested soil. Three-week-old seedlings from seed treated with M. coniospora had 60% and 58% fewer galls in two experiments than did seed...

− Nutrient acquisition by plants occurs in an environment characterized by complex interactions between roots, micro-organisms and animals, termed the rhizosphere. Competition for mineral elements in this sphere is high. The rhizosphere processes are driven by photosynthetically fixed carbon released by roots either directly to mycorrhizal fungal symbionts or as exudates fuelling a wider spectr...