Effects of increased deposition of atmospheric nitrogen on an upland moor: nitrogen budgets and nutrient accumulation.
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.
Pilkington
M G
MG
Department of Environmental and Leisure Studies, Manchester Metropolitan University, MMU Cheshire, Crewe Green Road, Crewe, Cheshire, CW1 5DU, UK. m.g.pilkington@mmu.ac.uk
Caporn
S J M
SJ
Carroll
J A
JA
Cresswell
N
N
Lee
J A
JA
Reynolds
B
B
Emmett
B A
BA
D000393:Air Pollutants / Q000032:analysis / Q000378:metabolism / Q000633:toxicity*; D001272:Atmosphere / Q000737:chemistry*; D018533:Biomass; D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods; D009584:Nitrogen / Q000032:analysis / Q000378:metabolism / Q000633:toxicity*; D010758:Phosphorus / Q000032:analysis; D010944:Plants / Q000187:drug effects; D011188:Potassium / Q000032:analysis; D012989:Soil Pollutants / Q000032:analysis / Q000378:metabolism / Q000633:toxicity
D000393:Air Pollutants; D012989:Soil Pollutants; D010758:Phosphorus; D009584:Nitrogen; D011188:Potassium