Hydrogen and nitrogen containing discharges emit intense radiation in a broad wavelength region in the VUV. The measured radiant power of individual molecular transitions and atomic lines between 117 nm and 280 nm are compared to those obtained in the visible spectral range and moreover to the RF power supplied to the ICP discharge. In hydrogen plasmas driven at 540 W of RF power up to 110 W ar...

To enable an accurate estimate of total excess nitrogen (N) in the North Atlantic, a new tracer TNxs is defined, which includes the contribution of organic nutrients to the assessment of N:P stoichiometric anomalies. We measured the spatial distribution of TNxs within the subtropical North Atlantic using data from a trans-Atlantic section across 24.5 N occupied in 2004. We then employ three dif...

[1] The Millennium Ecosystem Assessment scenarios for 2000 to 2050 describe contrasting future developments in agricultural land use under changing climate. Differences are related to the total crop and livestock production and the efficiency of nutrient use in agriculture. The scenarios with a reactive approach to environmental problems show increases in agricultural N and P soil balances in a...

Carbon and N losses reduce the agronomic value of compost and contribute to greenhouse gas (GHG) emissions. This study investigated GHG emissions during composting of straw-bedded manure (SBM) and wood chip-bedded manure (WBM). For SBM, dry matter (DM) loss was 301 kg Mg(-1), total carbon (TC) loss was 174 kg Mg(-1), and total nitrogen (TN) loss was 8.3 kg Mg(-1). These correspond to 30.1% of i...

Unsaturated zone N fate and transport were evaluated at four sites to identify the predominant pathways of N cycling: an almond [Prunus dulcis (Mill.) D.A. Webb] orchard and cornfield (Zea mays L.) in the lower Merced River study basin, California; and corn-soybean [Glycine max (L.) Merr.] rotations in study basins at Maple Creek, Nebraska, and at Morgan Creek, Maryland. We used inverse modelin...

The whole-farm nutrient mass balance (NMB) is an adaptive management tool that can be used to identify areas for improvement in nutrient management and to monitor progress over time. The objectives of this study were to (1) evaluate the trends of nitrogen and phosphorus mass balances of 27 New York State dairy farms over 6 to 10 yr, (2) identify specific management changes made by 4 case study ...

We formulate a dynamic evolutionary optimization problem to predict the optimal pattern by which carbon (C) and nitrogen (N) are co-allocated to fine-root, leaf, and wood production, with the objective of maximizing height growth rate, year by year, in an even-aged stand. Height growth is maximized with respect to two adaptive traits, leaf N concentration and the ratio of fine-root mass to sapw...

The North American tortoise Xerobates agassizii (synonym: Gopherus agassizii) consumes herbage and grasses produced from low and variable desert rains. Utilization of Sphaeralcea ambigua foliage and the grass Schismus barbatus were studied in 8 adult tortoises (2.3 kg body mass). The herbage contained more N but less fiber than the grass. Tortoises ingested and digested more dry matter and ener...