Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2005-4-12
pubmed:abstractText
Using stable N isotopes, the fate of effluent-derived N has been determined within a land based municipal effluent irrigation scheme. Over 900 metric tonnes(t) of effluent-derived N have been applied to 192 ha of production conifer forest near Rotorua (NZ) over the past 11 years. The effluent N has a natural isotopic signal, generated by the treatment process, allowing it to be traced into various components of the system. Using this isotopic signal, a realistic approximation of storage capacity of various components of the system has been generated, including a calculation of the contribution of effluent N exiting the catchment via stream flow. Forest storage accounts for 50% of the applied N with a considerable proportion of that immobilized in wood and soil. The wetland, although not intensively sampled, retains 115 t, (13%) of the applied N. Denitrification, including that occurring within the wetland, accounts for 23 t (3%). Nitrogen isotope data confirm that the rise in NO3 concentrations is directly attributable to effluent N. Currently 88% of NO3-N in the stream is effluent-derived. Using current N isotope values for the stream and extrapolating over the discharge period, export of effluent N via the stream is estimated as 263 t (29%) of the applied N. Overall the forest and wetland ecosystem has intercepted or denitrified 65% of applied N, with 29% lost to the stream, and 50 t (5%) unaccounted for. The forest ecosystem is currently over-supplied with N and a number of management implications flows from these findings. In the long term the continued application of effluent N to the current irrigation area is not sustainable.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
1025-6016
pubmed:author
pubmed:issnType
Print
pubmed:volume
41
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
13-30
pubmed:dateRevised
2009-11-3
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Using 15N to determine a budget for effluent-derived nitrogen applied to forest.
pubmed:affiliation
Department of Biological Sciences, University of Waikato, Private Bag 3105, Hamilton, New Zealand. wct@waikato.ac.nz
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't