Gypsum is hydrated calcium sulfate (CaSO 4 • 2H 2 O), and is often marketed as a soil " conditioner " for improving soil " tilth. " Compared to most other calcium-rich soil amendments, such as limestone, gypsum is relatively soluble in water, dissolving up to 2 g per liter. The solu-bility of gypsum, when either incorporated or surface applied, permits a quick release of calcium (Ca 2+) and sul...

he 23 US. Army installations engaged in plating employ a variety of techniques to treat wastewater. While some sites have implemented recovery and T reuse, a majority still find it advantageous to precipitate the metals and discharge the wastewater. Sludge is collected in clarifiers, treated by gravity thickening, then dewatered in pressure or vacuum filters, lagoons or drying beds. The dewater...

We evaluated the effect of polyacrylate polymers as immobilizing agents to aid phytostabilization of two mine soils. One soil had a very low pH (3.7) and a large Pb content, while the other was less acidic but had a greater content of Cu and Zn. Growth of perennial ryegrass (Lolium perenne L. cv. Victorian) was stimulated in polymer-amended soils. After ryegrass had been growing for 35 days, th...

In hops (Humulus lupulus L.), irrigation by flooding the inter-row can carry away suspended particles and minerals, causing gradients in soil fertility. The effect of more than 20 years on plants was evaluated two hop fields measuring plant variables multiple points along rows. a second experiment 1000 kg ha−1 lime applied incorporated into to assess whether liming could moderate any gradient c...