Critical loads of sulphur and nitrogen for freshwaters in Great Britain and assessment of deposition reduction requirements with the First-order Acidity Balance (FAB) model

被引:20
作者
Curtis, C
Allott, T
Hall, J
Harriman, R
Helliwell, R
Hughes, M
Kernan, M
Reynolds, B
Ullyett, J
机构
[1] UCL, ECRC, London WC1H 0AP, England
[2] Inst Terr Ecol, Huntingdon PE17 2LS, England
[3] SOAFD Freshwater Fisheries Lab, Faskally PH16 5LB, Pitlochry, Scotland
[4] MLURI, Aberdeen AB15 8QH, Scotland
[5] Inst Terr Ecol, Bangor Res Unit, Bangor LL57 2UP, Gwynedd, Wales
关键词
critical loads; acidification; nitrate; FAB model; acid deposition;
D O I
10.5194/hess-4-125-2000
中图分类号
P [天文学、地球科学];
学科分类号
07 ;
摘要
The critical loads approach is widely used within Europe to assess the impacts of acid deposition on terrestrial and freshwater ecosystems. Recent work in Great Britain has focused on the national application of the First-order Acidity Balance (FAB) model to a freshwaters dataset of 1470 lake and stream water chemistry samples from sites across Britain which were selected to represent the most sensitive water bodies in their corresponding 10 km grid square. A "Critical Load Function" generated for each site is compared with the deposition load of S and N at the time of water chemistry sampling. The model predicts that when catchment processes reach steady-state with these deposition levels, increases in nitrate leaching will depress acid neutralizing capacity (ANC) below the critical threshold of 0 mu eql(-1) at more than a quarter of the sites sampled, i.e. the critical load of acid deposition is exceeded at these sites. The critical load exceedances are generally found in upland regions of high deposition where acidification has been previously recognised, but critical loads in large areas of western Scotland are also exceeded where little biological evidence of acidification has yet been found. There is a regional variation in the deposition reduction requirements for protection of the sampled sites. The FAB model indicates that in Scotland, most of the sampled sites could be protected by sufficiently large reductions in S deposition alone. In the English and Welsh uplands, both S and N deposition must be reduced to protect the sites. Current international commitments to reduce S deposition throughout Europe will therefore be insufficient to protect the most sensitive freshwaters in England and Wales.
引用
收藏
页码:125 / 140
页数:16
相关论文
共 45 条
[1]   NITROGEN SATURATION IN NORTHERN FOREST ECOSYSTEMS [J].
ABER, JD ;
NADELHOFFER, KJ ;
STEUDLER, P ;
MELILLO, JM .
BIOSCIENCE, 1989, 39 (06) :378-386
[2]   The impact of nitrogen deposition on upland surface waters in Great Britain: A regional assessment of nitrate leaching [J].
Allott, TE ;
Curtis, CJ ;
Hall, J ;
Harriman, R ;
Battarbee, RW .
WATER AIR AND SOIL POLLUTION, 1995, 85 (02) :297-302
[3]  
BRAKKE DF, 1990, VERH INT VEREIN LIMN, V24, P146
[4]   Critical loads - Possibilities and constraints [J].
Bull, KR .
WATER AIR AND SOIL POLLUTION, 1995, 85 (01) :201-212
[5]  
*CLAG, 1994, CRIT LOADS AC UK
[6]  
CLAG Critical Loads Advisory Group, 1995, CRIT LOADS AC DEP UK
[7]  
*CLAG DEP FLUX, 1997, DEP FLUX AC COMP UK
[8]   Validation of the UK critical loads for freshwaters: Site selection and sensitivity [J].
Curtis, CJ ;
Allott, TEH ;
Battarbee, RW ;
Harriman, R .
WATER AIR AND SOIL POLLUTION, 1995, 85 (04) :2467-2472
[9]   The prediction of nitrate leaching with the first-order acidity balance (FAB) model for upland catchment in Great Britain [J].
Curtis, CJ ;
Allott, TEH ;
Reynolds, B ;
Harriman, R .
WATER AIR AND SOIL POLLUTION, 1998, 105 (1-2) :205-215
[10]  
CURTIS CJ, 1996, 12 ECRC U COLL LOND