Soil ameliorants

What will happen under field conditions is, however, highly uncertain. Laboratory experiments have been conducted under conditions of abundant nutrients and water, ideal temperatures, and no competition among experimental plants. Such conditions are rare in the field. The best prediction is that, whereas increases similar to those found in the laboratory are unlikely under field conditions, increased concentrations of CO2 are likely to ameliorate to some extent the detrimental effects of climate change. However, field-scale experiments under a variety of soils and climates and with several crop plants are needed to provide information on effects of climate change accompanied by higher concentrations of CO2 on agricultural productivity. 

Protection against physical stress Respon.se to high soil strength through inodilication of interface through lubrication and amelioration of rhizosphere soil... 

Webster, A.D. (2005). Sites and soils for temperate tree-fruit production their selection and amelioration , in Tromp J., Webster A.D. and Wertheim S.J. Fundamentals of Temperate Zone Tree Fruit Production, Backhuys Pubhshers, Leiden, 12-23. 

The problem of species changes during sampling and storage can be ameliorated in two ways. First, the soil component of interest can be measured in situ,... 

The CEC of soil is important from two perspectives. First, it retards the leaching loss of important cations from soil. Each year, calcium and magnesium are leached out of the soil, causing soils in humid regions to become acidic. This increased acidity must be ameliorated by the application of limestone (CaC03). Second, exchangeable cations are available to plants, and this characteristic allows soil to serve as a store of important soil nutrients such as potassium, calcium, and magnesium. 

Kahnt, G., Pfleiderer, H. and Hijazi, L.A. 1986. Effect of amelioration dosed of rock powder and rock sand on growth of agricultural plants and on physical characteristics of sandy and clay soil. Agronomy and Crop Science 157 169-180. 

Soil cation exchangeable capacity is an index used both to evaluate the nutrient and water retention ability of the soil and as an important basis for the amelioration of soil and to apply, rationally, fertiliser. Exchangeable cations absorbed by soil colloid include K+, Na+, Ca2+, Mg2+, Al3+ and H+. K+, Na+, Ca2+ and Mg2+ are exchangeable bases. Al3+ and H+ are exchangeable acids and the sum of these ions is known as the cation exchangeable capacity. Exchangeable Cu2+, Zn2+ and Mn2+ are present at negligible concentrations. 

Glaser, B., Lehmann, J., and Zech, W. (2002). Ameliorating physical and chemical properties of highly weathered soils in the tropics with charcoal—A review. Biol. Fertil. Soils 35, 219-230. 

Transfer of solute with and relative to the moving water and competitive adsorption of solutes are central to amelioration of saline and alkali soils, agricultural chemical location in soils and management of wastes in soils. This paper illustrates how space-like coordinates based on the distribution of the solid and the water help analyse these problems. We focus on the macroscopic or Darcy scale of discourse [6], which permits unambiguous measurement of the key elements of the flow equations, and we restrict ourselves to 1-dimensional flow, because that seems to limit analysable experiments. 

Vaughan, D., Sparling, G. P., and Ord, B. G., 1983. Amelioration of the phytotoxicity of phenolic acids by some soil microbes. Soil Biol. Biochem. 15, 613-614... 

In this context, speciation science seeks to characterise the various forms in which PTMs occur in soil or, at least, the main metal pools present in soil. Understanding speciation is important for assessing the potential of soil to supply micronutrients for plant growth or to contain toxic quantities of PTMs, and for determining amelioration procedures for soils at risk of causing the PTMs contamination of waterways. The residence time of an element in a soil depends on the mobility of its predominant forms. Speciation science is relevant to scientists with many different backgrounds and should be taken into consideration by legislators in the field of environmental protection. 

Harris, P.J.C. Allison, M. Smith, G. Kindness, H.M. and J. Kelley (2001) The potential use of waste-stream products for soil amelioration in peri-urban interface agricultural production systems.- In Drechsel, P. and D. Kunze (eds) (2001) Waste composting for urban and peri-urban agriculture - closing the rural-urban nutrient cycle in sub-Saharan Africa.- IWMI/FAO/CABI, Wallingford, UK. 

Haynes, R.J. and M.S. Mokolobate (2001) Amelioration of Al toxicity and P deficiency in acid soils by additions of organic residues a critical review of the phenomenon and the mechanisms involved.- Nutrient Cycling in Agroecosystems 59, 47-63. 

Qadir, M. Ghafoor, A. and G. Murtaza (2000) Amelioration strategies for saline soils a review.- Land degradation and development 11, 501-521. 

Saline soils, 407-411 Sodium levels, 407 Leaching, 420 Amelioration, 422 Toxicity, 408... 

Mineral dissolution kinetics influence such phenomena as development of soil fertility, amelioration of the effects of acid rain, formation of karst, acid mine drainage, transport and sequestration of contaminants, sequestration of carbon dioxide at depth in the earth, ore deposition, and metamorphism. On a global basis, mineral weathering kinetics are also involved in the long-term sink for CO2 in the atmosphere ... 

Although humus constitutes, generally, only a small part of the soil (below 10%), it exerts a profound influence on the physical, chemical, and biological properties of the soil. Attempts have been made to attribute particular influences to specific compounds in humus. The observation of the ameliorative effect of polysaccharides on soil structure has greatly stimulated research on the nature of soil carbohydrates. 

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