http://precedings.nature.com/tags/phosphorus Recently posted documents tagged with 'phosphorus' Nature Publishing Group en Nature Precedings http://precedings.nature.com/images/header_logo.gif http://precedings.nature.com http://dx.doi.org/10.1038/npre.2009.3763.1 Eutrophication is a threat to quality of surface and ground water bodies (SWB) and to bio-diversity of the aquatic eco-system. One of the causes of P accumulation in SWB is its excess application as a fertilizer on agricultural lands. Phosphorus buffering also contributes to eutrophication and remains a major problem years after the release of P is brought under control. It could be discerned from many experiments conducted world over that addition of small amount of P can remove excess P from soils, provided the solution P is maintained in such a manner that productivity is sustained, and nano-P could possibly play a role in it. In such endeavours, P must be applied to soils in amount exact to the requirement of crop. Of course ecological cautions of use of nano-P must not be ignored. Nanoscience approach can deal with the twin contradictions – between low solubility and excess application by opening new avenues to improve nutrient use efficiency and reduce P build ups in soils and thereby reducing its load in SWB and checking contamination in drinking water. Many P fertilizers contain heavy metals, which can be eliminated by nano-P. The success of zeophonics demonstrates that a system can be made self-supporting, and can supply nutrients to plants for a long time. To comprehend P dynamics, land and SWB system must be treated holistically, and sub-divided into components, each with realistic independent system-variables coupled with the processes, which tie these system variables. In nano-P ventures high resolution imaging not only provides evidence of the changes that occur in various phases, but is also an indispensable tool to understand how P dynamics operate. http://dx.doi.org/10.1038/npre.2009.3763.1 Wed, 16 Sep 2009 08:15:14 UTC Eutrophication: Can nanophosphorous control this menace? doi:10.1038/npre.2009.3763.1 2009-09-16 Deepika Bhalla Nature Precedings 2009-09-16T08:15:14Z Presentation Chemistry Ecology Earth & Environment http://creativecommons.org/licenses/by/3.0/ http://precedings.nature.com/documents/1993/version/1 Nutrients limit plant growth in many ecosystems, and many species develop adaptations to either obtain more nutrients or to avoid losses. Much past ecological work has focused either on temperate nitrogen-limited systems or has addressed infertile soils as a single entity, rather than addressing the nature of the limitation. Although low nitrogen (N) and phosphorus (P) soils are found worldwide, the consequences of N and P limitation for plants may vary due to fundamental differences in the soil mobility, availability, uptake, and cellular uses of N and P. Using a well-studied chronosequence in the Hawaiian Islands, which contains both low N and P soils but which is dominated by similar plant communities, foliar N and P plant responses to fertilization were examined across a diverse group of species and life forms. Here it is shown that in response to N fertilization, foliar N concentrations do not significantly increase. In contrast, P fertilization leads to highly elevated foliar P concentrations and lower N:P values. This accumulation of P is evident across all species, occurs regardless of site fertility, results in increased concentrations of P in both inorganic and organic forms, and may be highly advantageous due to the patchy nature of soil P availability. Results indicate that greater variation in foliar P than foliar N after fertilization transcends soil nutrient availability and may be widespread among ecosystems. Such P accumulation means that N and P concentrations may not be in close association after pulses of soil P. It also provides a mechanism whereby ecosystem P limitation may be overcome with external inputs more easily than N limitation and points for the need to think about N and P limitation not just as infertile stressful conditions for plants, but as two fundamentally different phenomena. http://precedings.nature.com/documents/1993/version/1 Mon, 23 Jun 2008 08:01:57 UTC Mechanisms to overcome ecosystem nitrogen and phosphorus limitation hdl:10101/npre.2008.1993.1 2008-06-23 Rebecca Ostertag Nature Precedings 2008-06-23T08:01:57Z Manuscript Ecology Plant Biology http://creativecommons.org/licenses/by/3.0/ http://dx.doi.org/10.1038/npre.2008.1740.1 A number of mining sites worldwide, particularly gold mines, have tailings management facilities (TMFs) that contain high levels of arsenic. Current closed mine site regulatory agencies tend to prefer revegetation of TMFs as part of the mandated reclamation activities. At many sites, often in polar regions, vegetation is difficult to establish either directly on the tailings or on the coarse-rock covers due to nutrient poor soils, phytotoxicity problems, and/or a less than optimum climate. Addition of phosphorus-based fertilizers to the tailings and/or cover material is commonly considered in order to promote the revegetation process and – ideally – allow the site owners to discharge their closure duties as rapidly as possible. However, due to the similar geochemistry of arsenic and phosphorus oxyanion species, this type of mine closure strategy may have unintended consequences regarding arsenic mobility on and off the site. This document reviews the current state-of-the-art regarding mobilization of arsenic by phosphate ions, and identifies relevant risks and opportunities of using this information to better manage closed mine sites. http://dx.doi.org/10.1038/npre.2008.1740.1 Mon, 31 Mar 2008 15:37:47 UTC Potential Impacts of Tailings and Tailings Cover Fertilization on Arsenic Mobility in Surface and Ground Waters doi:10.1038/npre.2008.1740.1 2008-03-31 Sierra Rayne Nature Precedings 2008-03-31T15:37:47Z Manuscript Chemistry Earth & Environment http://creativecommons.org/licenses/by/3.0/ http://precedings.nature.com/documents/1482/version/1 All known life requires phosphorus (P) in the form of inorganic phosphate (PO4- or Pi) and phosphate-containing organic molecules. Pi serves as the backbone of the nucleic acids that constitute genetic material and as the major repository of chemical energy for metabolism in polyphosphate bonds. Arsenic (As) lies directly below P on the periodic table and so the two elements share many chemical properties, although their chemistries are sufficiently dissimilar that As cannot directly replace P in modern biochemistry. Arsenic is toxic precisely because As and P are similar enough that organisms attempt this substitution. We hypothesize that ancient biochemical systems, analogous to but distinct from those known today, could have utilized arsenate in the equivalent biological role of phosphate. Organisms utilizing such “weird life” biochemical pathways may have supported a “shadow biosphere” at the time of the origin and early evolution of life on Earth or on other planets. Such organisms may even persist on Earth today, undetected, in unusual niches. http://precedings.nature.com/documents/1482/version/1 Wed, 02 Jan 2008 22:43:38 UTC Did nature also choose arsenic? hdl:10101/npre.2008.1482.1 2008-01-02 Felisa Wolfe-Simon Nature Precedings 2008-01-02T22:43:38Z Manuscript Chemistry Evolutionary Biology http://creativecommons.org/licenses/by/3.0/