classical soil mechanics involves the study of fully saturated soils. however, many problems encountered in geotechnical engineering practice involve unsaturated soil, in which behavior is significantly different from classical saturated soil. negative pore pressure and capillary forces develop a virtual cohesion between the grains of semi saturated soils. this kind of cohesion is dependent on ...

American chestnut trees once dominated vast areas of deciduous forest in eastern North America, but the exotic chestnut blight almost eliminated the species from the region. Introduction of blight-resistant American chestnut hybrids will probably start in the next decade after many years of tree breeding. What were the historic effects of chestnut on forest soils, and what changes may follow re...

Movement of mineral dust by the atmosphere has been underway for ages, but efforts to assess its magnitude and significance have come largely in the last century. Attempts to identify and understand effects of the dust on soils are even more recent, mostly in the last 30 years. Airborne movements have several forms. Dust is transported by large storms that can be spectacular. Dust is also moved...

There is a need to select high quality forage legumes that are acid soil-tolerant, drought resistant, and persistent under the close defoliation associated with intensive pasture systems in the humid tropics. A greenhouse pot study was conducted to determine forage legume seedling growth (10 week-old) and regrowth (5 weeks after clipping to an 8-cm residual stubble) responses of ‘Amarillo’ pere...

The geotechnical classification of soils by laboratory tests is usually used to determine the class soil under study for its subsequent use in construction projects. interest certainly well displayed. Indeed, an experimental program has been developed with aim studying area. To this end, oedometric and shear were carried out on several samples laboratory. This made it possible understand “stres...

In Iran, using the hand excavated pits (wells) have been more common compared to other countries. As a matter of fact, recent years, utilizing the dynamic probing test (DPT) in these types of pits has been significantly developed in Iran. This is while the standard state of doing this test is from the ground level. In this work, the dynamic probing test is carried out in two similar wells with ...

Phytoremediation is a set of technologies that uses plants to clean up contaminated soils and groundwater. Phytoremediation is environmentally friendly, successful and cost-effective compared to other in situ methods such as the electrokinetic method. In this work, two local plant species, Chrysanthemum and Pelargonium, were examined for their ability to uptake lead from lead contaminated soils...

The successful establishment of agricultural crops depends on sowing quality, machinery performance, soil type and conditions, among other factors. This study evaluates the operational quality of mechanized peanut sowing in three soil types (sand, silt, and clay) with variable moisture contents. The experiment was conducted in three locations in the state of São Paulo, Brazil. The track-samplin...

Vegetated buffer strips were evaluated for their ability to remove waterborne Cryptosporidium parvum from surface and shallow subsurface flow during simulated rainfall rates of 15 or 40 mm/h for 4 h. Log(10) reductions for spiked C. parvum oocysts ranged from 1.0 to 3.1 per m of vegetated buffer, with buffers set at 5 to 20% slope, 85 to 99% fescue cover, soil textures of either silty clay (19:...