Pilkington M G, Caporn S J M, Carroll J A, Cresswell N, Lee J A, Reynolds B, Emmett B A
Department of Environmental and Leisure Studies, Manchester Metropolitan University, MMU Cheshire, Crewe Green Road, Crewe, Cheshire, CW1 5DU, UK.
Environ Pollut. 2005 Dec;138(3):473-84. doi: 10.1016/j.envpol.2005.04.011.
This study was designed to investigate the effect of long-term (11 years) ammonium nitrate additions on standing mass, nutrient content (% and kg ha(-1)), and the proportion of the added N retained within the different compartments of the system. The results showed that more than 90% of all N in the system was found in the soil, particularly in the organic (Oh) horizon. Added N increased the standing mass of vegetation and litter and the N content (kg N ha(-1)) of almost all measured plant, litter and soil compartments. Green tissue P and K content (kg ha(-1)) were increased, and N:P ratios were increased to levels indicative of P limitation. At the lowest treatment, most of the additional N was found in plant/litter compartments, but at higher treatments, there were steep increases in the amount of additional N in the underlying organic and mineral (Eag) horizons. The budget revealed that the proportion of added N found in the system as a whole increased from 60%, 80% and up to 90% in response to the 40, 80 and 120 kg N ha(-1) year(-1) treatments, respectively.
本研究旨在调查长期（11年）添加硝酸铵对系统不同组分的现存生物量、养分含量（%和kg ha⁻¹）以及添加氮素在系统内不同组分中的留存比例的影响。结果表明，系统中超过90%的氮存在于土壤中，尤其是在有机（Oh）层。添加氮增加了植被和凋落物的现存生物量以及几乎所有测量的植物、凋落物和土壤组分的氮含量（kg N ha⁻¹）。绿色组织的磷和钾含量（kg ha⁻¹）增加，氮磷比增加到表明磷限制的水平。在最低处理水平下，大部分额外添加的氮存在于植物/凋落物组分中，但在较高处理水平下，下层有机和矿质（Eag）层中额外添加的氮量急剧增加。预算显示，随着分别为40、80和120 kg N ha⁻¹ year⁻¹的处理，整个系统中添加氮的留存比例分别从60%、80%增加到90%。
