06/02326 Effect of reference state on the performance of energy and exergy evaluation of geothermal district heating systems: Balcova example: Ozgener, L. et al. Building and Environment, 2006, 41, (6), 699–709.

• Publisher: Elsevier Science
• Year: 2006
• Weight: 166 KB
• Volume: 47
• Category: Article
• ISSN: 0140-6701
• DOI: 10.1016/s0140-6701(06)82334-9

✦ Synopsis

13 Alternative energy supplies (solar energy) 06•02324 The recovery over several seasons of ~SN-labelled fertilizer applied to Miscanthus × giganteus ranging from 1 to 3 years old Christian, D. G. et al. Biomass and Bioenergy, 2006 30, (2) 125-133. In a field experiment 60 kg N ha 1 of 15N-labelled fertilizer was applied to Miscanthusxgiganteus planted 1, 2 or 3 years previously. Plots were destructively sampled at senescence 1, 2 or 3 years after labelled N was applied with aerial biomass harvested in intervening years. The objective was to quantify N uptake and distribution within the plant, labelled N remaining in the soil (0-50 cm) and overall losses. The authors report results for the second and third years and compare them to first year data previously published. Total biomass more than doubled over 2 years of growth but N concentration did not change. More labelled N was recovered by 3-year-old plants (65%) than by 2year-old plants (55%) or l-year-old plants (38%). Between 19% and 26% was found in the soil (0 50 cm) and more than 85% of this N was in topsoil (0-23 cm). Total recovery in plant and soil was 60-71% for 1year-old plants. 76 81% for 2-year-old plants and 84% for 3-year-old plants. Overall losses (18 24%) from 2-and 3-year-old plants are similar to those from arable and permanent grass crops on the same soil type given similar amounts of N. Labelled (and unlabelled) N stored in rhizomes will take several years to decline because of transfers between rhizomes and shoots. Similarly, labelled N remaining in soil will decline slowly over many years; any N mineralized in subsequent years will be subject to plant uptake and/or loss.