Soil modification

Soil conditioning Soil disinfectant Soil flushing Soil fumigants Soiling of fabrics Soil modification Soil pesticides Soil remediation Soils... 

Other Applications. Polyacrylamides are used in many additional appUcations including soil modification (138), dust control (139,140), humidity control (141), protein purification (142), removal of barium from wastewater (143), and removal of arsenic from hydrocarbons (144). Polyacrylamides have been used for many years in sugar manufacture and textile treatment. 

Frequent changes in contaminant type and concentration in the feed soil can disrupt the efficiency of the soil-washing process. To accommodate changes in the chemical or physical composition of the feed soil, modifications to the wash fluid formulation and the operating settings may be required. Alternatively, additional feedstock preparation steps, such as blending soils to provide a consistent feedstock may be appropriate.77,83... 

After landfill cover completion, the plant cover may be changed but soil modification may be impractical. Therefore, good soil design and correct construction practices are of utmost importance to the success of the ET cover. 

Agricultural interests have amended existing soil properties to improve productivity their experience demonstrates the power of knowledge of soil properties and the ability to control them.14 A primary benefit of these amendment efforts was improvement in soil-water-holding capacity and increased rate of water removal from all soil layers by plants. The benefits of soil modification remain effective for decades. There is opportunity for similar improvements in soil during ET landfill cover design and construction. Control of ET cover soil properties has potential to enhance cover performance and should add little to construction cost. 

Boyd SA, Lee J-F, Mortland MM (1988) Attenuating organic contaminant mobility by soil modification. Nature 333 345-347... 

By using renewable carbon from biomass, an improvement in the CO2 balance can be achieved. However, significant effects beyond the impacts on greenhouse gas emissions are possible, e.g., soil modification, eutrophication, impact on biodiversity, land requirements and water consumption. These aspects depend on different factors like feedstock type, scale of production, cultivation and land-management practices, location and downstream processing routes. The environmental implications of agriculture are sometimes difficult to assess by the LCA methodology and require further research. 

Edmonds, R. L., T. B. Thomas, and J. J. Rhodes. 1991. Canopy and soil modification of precipitation chemistry in a temperate rain forest. Soil Science Society of America Journal 55 1685-1693. 

Some plants can alter the immediate environment around their roots by exuding materials that change soil acidity. This enhances, by three or more orders of magnitude, the solubility of such essential elements such as iron. These plants have a finely tuned biofeedback control that enhances soil fertility precisely at the root surface without altering the rest of the soil. This, then, minimizes the energy cost to the plant of soil modification (Olsen et al., 1981). Root crops and rhizosphere bacteria secrete acids into the soil solution to raise the solubility of solid-phase phosphates (highly pH dependent) in their immediate neighborhoods (Russell, 1961). 

Fig. 4 An example of incorporating a soil modification mixer in a sealed digging system [4].

The addition of polymeric agents is effective in soil modification. For optimal benefit, of course, it is necessary to disperse the polymer uniformly. Currently used mixing methods are twin screw mixer, mixing shovel, and backhoe. Figure 4 illustrates an example of a sealed digging system to which a twin screw mixer is incorporated. 

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