Glyphosate-based weed control products are among the most widely used broad-spectrum herbicides in the world. The herbicidal properties of glyphosate were discovered in 1970, and commercial formulations for nonselective weed control were first introduced in 1974 (Franz et al. 1997). Formulations of glyphosate, including Roundup® Herbicide (RU)1 (Monsanto Company, St. Louis, MO), have been extensively investigated for their potential to produce adverse effects in nontarget organisms. Governmental regulatory agencies, international organizations, and others have reviewed and assessed the available scientific data for glyphosate formulations and independently judged their safety. Conclusions from three major organizations are publicly available and indicate RU can be used with minimal risk to the environment (Agriculture Canada 1991; USEPA 1993a; WHO 1994). Several review publications are available on the fate and effects of RU or glyphosate in the environment (Carlisle and Trevors 1988;Smith and Oehme 1992 ; Malik et al. 1989;Rueppel et al. 1977; Sullivan and Sullivan 1997;Forestry Canada, 1989). In addition, several books have been published about the environmental and human health considerations of glyphosate and its formulations (Grossbard and Atkinson 1985; Franz et al. 1997). In addition, RU and other glyphosate formulations have been selected for use in a number of weed control programs for state and local jurisdictions in the United States. Many of these uses require that ecological risk assessments be conducted in the form of Environmental Impact Statements or Environmental Assessments. These documents are comprehensive and specific to local use situations. Documents are available for risk assessments in Texas, Washington, Oregon, Pennsylvania, New York, Virginia, and other states (USDA 1989;USDA 1992;USDA 1996;USDA 1997;USDI 1989; Washington State DOT 1993).

Ecotoxicological Risk Assessment for Roundup ® Herbicide

Statistics for analytical chemistry

More than 30 years have passed since the first application of nuclear magnetic resonance (NMR) spectroscopy to soil organic matter (SOM). Since then, there has been an explosion of applications using 1H, 13C, 31P, and 15N NMR on both solution and solid-state samples. These have greatly enhanced our

Applications of NMR to soil organic matter analysis : History and prospects

The transformations of soil organic phosphorus are described and organized in a conceptual model. Microbial uptake of P and its subsequent release and redistribution play a central role in the soil organic P cycle. Interactions with soil minerals and stabilization of organic matter and associated P in organo-mineral complexes determine the persistence and buildup of organic P through soil development, in different ecosystems and under varying management. An understanding of organic P turnover in soils will greatly aid assessment of P fertility in many agricultural and native systems.

Dynamics of soil organic phosphorus

We compiled regional and continental data on inorganic nitrogen (N) in seepage and surface water from temperate forests. Currently, N concentrations in forest waters are usually well below water qu...

Leaching of nitrate from temperate forests effects of air pollution and forest management

NH4NO3 (1 M) has been used as an extractant for soil exchangeable cations, exchangeable acidity and aluminum. The results obtained using NH4NO3 were identical to those using KC1 and NH4Cl as extractants for the purpose of evaluating soil chemical status. The NH4NO3 extraction has practical analytical advantages.

Ammonium nitrate as extractant for soil exchangeable cations, exchangeable acidity and aluminum

31P-NMR spectra of humic acids: A comparison of four different raw humus types in Norway

A method for determination of the climate gases CH4, CO2 and N2O in air samples and soil atmosphere was developed using GC-MS. The method uses straightforward gas chromatography (separation of the gases) with a mass spectrometric detector in single ion mode (specific determination). The gases were determined with high sensitivity and high sample throughput (18 samples h−1). The LOD (3σ) for the gases were 0.10 µL L−1 for CH4, 20 µL L−1 for CO2 and 0.02 µL L−1 for N2O. The linear range (R2 = 0.999) was up to 500 µL L−1 for CH4, 4000 µL L−1 for CO2 and 80 µL L−1 for N2O. The samples were collected in 10 mL vials and a 5 μL aliquot was injected on column. The method was tested against certified gas references, the analytical data gave an accuracy within ±5% and a precision of ±3%. The presence of ≤10% by volume of C2H2 (often used experimentally to prevent N2 formation from N2O) did not interfere with detection for the targeted trace gases.

Gunnar Ogner

Papers

Ammonium nitrate as extractant for soil exchangeable cations, exchangeable acidity and aluminum

31P-NMR spectra of humic acids: A comparison of four different raw humus types in Norway

Determination of CH4, CO2 and N2O in air samples and soil atmosphere by gas chromatography mass spectrometry, GC-MS

A comparison of four different raw humus types in Norway using chemical degradations and CPMAS 13C NMR spectroscopy

No general effect of ozone on foliar nutrient concentrations in mature scions of grafted Picea abies trees.