Phosphorus, effect leaching

Stevens P. A., Harrison A. F., Jones H. E., Williams T. G., and Hughes S. (1993) Nitrate leaching from a Sitka spruce plantation and the effect of fertilisation with phosphorus and potassium. Forest Ecol. Manage. 58, 233-247. 

Amino-Resins. The most widely studied leach-resistant systems are the amino-resins. Goldstein and Dreher (9S) first applied these systems as fire retardants. Basically, the amino-resin systems involve the combination of a nitrogen source (i.e., urea, melamine, guanidine, or dicyandiamide) with formaldehyde to produce a methylo-lated amine. The new product is then reacted with a phosphorus compound such as phosphoric acid. Because there is a synergistic effect between the phosphorus and the nitrogen, reduced loading... 

The magnitude and overall effect of a macronutrient on oil yield is dependent upon environment, available water, specific plant type and its stage of development. For example, nitrogen will generally increase the mass of plant material produced per unit area independent of soil type. Also, it has been determined that for herbaceous plants the oil content of particular selection remains constant irrespective of plant size. Therefore, as nitrogen can cause an increase in overall dry matter, it can have a positive effect on oil production. Phosphorus and potassium can also cause an increase in dry matter, however, their presences in soil does not necessarily mean that they are available to the plant. In acid soils, for example, phosphorus is not readily accessible while potassium is easily leached away. Generally, in most neutral or alkaline soils the effect of phosphorus and potassium on oil content is less dramatic than nitrogen unless a true deficiency is found. 

Setala, H., Matikainen, E., Tyynismaa, M. and Huhta, V. (1990) Effects of soil fauna on leaching of nitrogen and phosphorus from experimental systems simulating coniferous forest floor. Biology and Fertility of Soils 1 0, 1 70-1 77... 

In the ligand series synthesized, l,l -bis(diphenylphosphino)cobaltocenium hexafluorophosphate (5) proved to be particularly suitable. In [BMIM]]PF,5], high catalyst activity (810 h ), high selectivity for aldehydes (94%) and for the n-product (n/i = 16.2), and above all no detectable catalyst leaching were demonstrated. The analogous cobaltocenium (6), in which an alkyl bridge was placed between the cyclopentadienyl and the phosphorus atom, yields much less positive effects (e.g., TOF = 66 h ). This result can be explained by the electronic influence of the central... 

Weathering can release essential plant nutrients into the soil solution, which is taken up by plant roots carrying nutrients with it. One of the most important of these is ion, which goes into solution from the weathering of minerals such as potassium feldspar, KAlSijOj. Nutrient phosphorus is released in the weathering of hydroxyapatite, Ca50H(P04)3. Selenium is leached from minerals that contain this element, too much of which can be toxic and a deficiency of which can cause adverse health effects, especially in livestock, as well (see Chapter 10, Section 10.5). 

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