Human impacts on the nitrogen cycle: a global problem judged from a local perspective

This chapter revisits the major problems relating to man-made disturbances in the global nitrogen (N) cycle, and links the local findings from the project to the large-scale effects. The human transformation of atmospheric N2to chemically and biologically more reactive species causes a number of env...

Full description

Saved in:
Bibliographic Details
Published in:Ambio 1997-08, Vol.26 (5), p.321-325
Main Authors: Hessen, D.O. (Oslo Univ. (Norway). Biologisk Inst.), Henriksen, A, Hindar, A, Mulder, J, Toerseth, K, Vagstad, N
Format: Article
Language:English
Subjects:
Acidification
Agricultural runoff
Agricultural soils
AZOTE
BOSQUES
CICLO BIOGEOQUIMICO
CYCLE BIOGEOCHIMIQUE
CYCLING
ENVIRONMENTAL IMPACT
ESCORRENTIA
EUTROFIZACION
EUTROPHICATION
EUTROPHISATION
FARMLAND
Forest soils
FORESTS
FORET
Fresh water
IMPACT SUR L'ENVIRONNEMENT
IMPACTO AMBIENTAL
NITROGEN
NITROGENO
Organic farming
POLLUTION BY AGRICULTURE
POLLUTION DE L'EAU
POLLUTION PAR L'AGRICULTURE
POLUCION DEL AGUA
POLUCION POR LA AGRICULTURA
RUISSELLEMENT
RUNOFF
Surface runoff
TERRE AGRICOLE
TIERRAS AGRICOLAS
WATER POLLUTION
Watersheds
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:This chapter revisits the major problems relating to man-made disturbances in the global nitrogen (N) cycle, and links the local findings from the project to the large-scale effects. The human transformation of atmospheric N2to chemically and biologically more reactive species causes a number of environmental effects. The focus of this project has been budget estimates of N for two large watersheds with a set of subcatchments in southern Norway, accompanied by process studies to explain patterns of retention and runoff of N. Atmospheric inputs were close to 2.5 mg N m-2yr-1and by far the dominant source of N for the sparsely populated, heathland dominated watershed. Low retention and apparent N saturation could be accredited to high atmospheric inputs of N, but also hydrology, poorly developed soils and terrestrial P limitation. In this acidified watershed, nitrate contributed nearly 50% to surface water acidification, underlining the importance for strong cuts in NOxand${\rm NH}_{{\rm x}}$emissions. P concentrations were low, frequently $
ISSN:0044-7447
1654-7209