<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Mosello, R. , Calderoni A. , Marchetto A. , Brizzio M. C. , Rogora M. , Passera S. , Tartari. G. A.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Nitrogen budget of Lago Maggiore: the relative importance of atmospheric deposition and catchment sources</style></title><secondary-title><style face="normal" font="default" size="100%">J. Limnol.</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">atmospheric deposition</style></keyword><keyword><style  face="normal" font="default" size="100%">catchment</style></keyword><keyword><style  face="normal" font="default" size="100%">Lago Maggiore</style></keyword><keyword><style  face="normal" font="default" size="100%">nitrogen budget</style></keyword><keyword><style  face="normal" font="default" size="100%">river water</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2001</style></year></dates><volume><style face="normal" font="default" size="100%">60</style></volume><pages><style face="normal" font="default" size="100%">27-40</style></pages><abstract><style face="normal" font="default" size="100%">Hydrological and chemical data of 1996 and 1997 are used to evaluate the relative contributions of atmospheric deposition and
urban/industrial wastewaters to the nitrogen budget of Lago Maggiore. The atmospheric load of nitrogen was about 80% of the total
input to the lake, with negligible variations in dry (1997) and wet (1996) years. A comparison of the two study years with the yearly
N budgets evaluated from 1978 to 1998, showed that the N load was higher with increasing amounts of precipitation/water inflow.
Soils and vegetation act as N sinks; the % retention varies between 40-60% for the forested catchments with low population density
in the central-northern part of the basin, to values close to zero or even negative in the south, indicating a net leaching from the
soils. The Traaen &amp; Stoddard (1995) approach revealed that all the catchments of the major inflowing rivers were oversaturated
with nitrogen. The long-term trend of nitrogen concentrations in Lago Maggiore (1955-99) is analogous to the trend for atmospheric
deposition (1975-99), which is related to emissions of nitrogen oxides and ammonia in the atmosphere. The relationships between
the present N load and in-lake concentrations are discussed using a budget model, which is also used to infer the pristine load of N.
The close relationships between N trends in lakes Maggiore, Como and Iseo, and the geographical and anthropogenic features common
to their catchments, suggest that the results obtained for Lago Maggiore can be extended to a wider area.</style></abstract><custom1><style face="normal" font="default" size="100%">General</style></custom1></record></records></xml>
