Nutrient cations

Similar information on temperature, dissolved oxygen, salinity and density has been published for the Northern North Atlantic , and in more detail for the seas around the British Islesthe latter also includes hydro-graphic data on the contents of dissolved metals (Zn, Ni, Cu, Cd, Hg, Mn) and nutrient cations (phosphate, nitrate). 

An example of the fragile nutrient balance in peat bogs is given in Table 7.2 for a blanket bog in northern England. The table shows the losses of N through erosion of the peat, and the losses of nutrient cations through leaching and removal in stream water. 

For nutrient cations, the formation of metal complexes can increase their uptake by increasing the total concentration of the metal in solution, which, in... 

Nutrient cation uptake) — (nutrient anion uptake) = ions exuded (5.41) and for NOf-feeding plants ... 

By promoting decomposition and by retaining nitrogen, phosphorus, and nutrient cations, the soil prevents the rapid loss of essential elements to groundwater and rivers. The result of this process is a net accumulation of available nutrients in the soil and, thus, an enhanced productivity at all trophic levels of the ecosystem. 

Until recently, understanding of the effects of acidic deposition on soils was limited. However, current research has shown that acidic deposition has chemically altered forest soils with serious consequences for acid-sensitive ecosystems. Soils compromised by acidic deposition lose their ability to neutralize continuing inputs of strong acids, provide poorer growing conditions for plants, and extend the time needed for ecosystems to recover from acidic deposition. Acidic deposition has altered and continues to alter base-poor forest soils in three important ways. Acidic deposition depletes available calcium and other nutrient cations (e.g., magnesium, potassium) from soil facilitates the mobilization of dissolved inorganic aluminum into soil water and increases the accumulation of sulfur and nitrogen in soil. 

Finally, there may be adverse effects on other tree species. For example, one might speculate that hardwood species such as white ash and basswood that prefer rich sites high in nutrient cations may experience problems in areas where nutrient cations have been depleted by acidic deposition. However, additional research is needed to assess more fully the response of these tree species to acidic deposition. 

Treeby, M., Marschner, H., Romheld, V., 1989. Mobilization of iron and other micro-nutrient cations from a calcareous soil by plant-borne, microbial, and synthetic metal chelators. Plant Soil 114, 217-226. 

Mortensen has emphasized that HA complexes a number of nutrient cations and in so doing may alter the amounts taken up by plants thus... 

Soils deficient in sulfur do not support plant growth well, largely because sulfur is a component of some essential amino acids and of thiamin and biotin. Sulfate ion is generally present in the soil as immobilized insoluble sulfate minerals, or as soluble salts that are readily leached from the soil and lost as soil water runoff. Unlike the case of nutrient cations such as K, little sulfate is adsorbed to the soil (that is, bound by ion exchange binding) where it is resistant to leaching while still available for assimilation by plant roots. 

Foster, N.W., Nicolson, J.A. and Hazlett, P.W. 1989. Temporal variation in nitrate and nutrient cations in drainage waters from a deciduous forest. J. Environ. Qual, 18 238-244. 

Zarin, D. J. Johnson, A. H. (1995). Base saturation, nutrient cation, and organic matter increases during early pedogenesis on landslide scars in the Luquillo Experimental Forest, Puerto Rico. Geoderma, Vol. 65, No. 3d, p>p. 317-330, ISSN 0016-7061 Zhao, J. B. Hao, Y. F. Yue, Y. L. (2006). Change of paleosol and climate during middle Holocene in Luochuan area of Shaanxi Province. Quaternary Science, Vol. 26, No. 6,... 

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