<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Piñol, J</style></author><author><style face="normal" font="default" size="100%">Avila, a</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Streamwater pH, alkalinity, p CO 2 and discharge relationships in some forested Mediterranean catchments</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Hydrology</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Catchments</style></keyword><keyword><style  face="normal" font="default" size="100%">montseny</style></keyword><keyword><style  face="normal" font="default" size="100%">prades</style></keyword><keyword><style  face="normal" font="default" size="100%">precipitation (voyant)</style></keyword><keyword><style  face="normal" font="default" size="100%">Streamwater chemistry</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1992</style></year></dates><volume><style face="normal" font="default" size="100%">131</style></volume><pages><style face="normal" font="default" size="100%">205-225</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The streamwater chemistry of four catchments at Prades and one catchment at Montseny (NE Spain) is described and the relationships between streamwater alkalinity, pH and pCO 2 with discharge and that between pH and alkalinity are highlighted. At Montseny, results from a subsurface seepage are also presented. The Prades and Montseny catchments have similar vegetation (dense forest of holm oak. Quercus ilex L.) and lithology (phyllites). However, the catchments differ strongly in their hydrological behaviour: only 8-15% of the rainfall passes to the stream from the two gauged Prades catchments, whereas the Montseny catchment provides 50% of rainfall to the stream. Hence the mineralization of streamwaters is much higher in the Prades catchments. All the streams studied show an inverse relationship between alkalinity and discharge. Although pH also decreases with discharge in the Montseny catchment. it remains high during high flows in the Prades catchments. The Prades streamwater chemistries are determined by the solubility equilibrium of calcite: at high flows alkalinity decreases and, as a result of calcite solubility controls, this change results in an increase in pH. Consequently, pH and log(alkalinity) are either negatively correlated or uncorrelated in the Prades streams. At Montseny, the relationship between pH and alkalinity is significantly positive: calcite solubility controls do not come into play. All waters analyzed show an excess pCO 2 (epC02) with respect to atmospheric concentrations. The highest epC02 values usually correspond to low flows. However, study of the variation of epCO2 during 15 individual storm events sampled at Montseny shows that epCO 2 increases with discharge. At Prades, the degassing of epCO 2 in the stream channel produces calcite precipitation.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Piñol, J</style></author><author><style face="normal" font="default" size="100%">LLEDO, M J</style></author><author><style face="normal" font="default" size="100%">Escarre, A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Hydrological balance of two Mediterranean forested catchments (Prades, northeast Spain)</style></title><secondary-title><style face="normal" font="default" size="100%">Hydrological Sciences Journal</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Catchments</style></keyword><keyword><style  face="normal" font="default" size="100%">evapotranspiration (voyant)</style></keyword><keyword><style  face="normal" font="default" size="100%">hydrological response</style></keyword><keyword><style  face="normal" font="default" size="100%">Precipitation</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1991</style></year></dates><publisher><style face="normal" font="default" size="100%">Taylor &amp; Francis</style></publisher><volume><style face="normal" font="default" size="100%">36</style></volume><pages><style face="normal" font="default" size="100%">95-107</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Abstract Precipitation and discharge have been measured for several years in two small forested catchments located in the Mediterranean area of Spain. Actual evapotranspiration has been calculated as the difference between annual precipitation and discharge. Results show that: (a) most of the precipitation is evaporated rather than lost by streamflow, even in the most humid years; (b) there is a high inter-annual variability both in discharge and evapotranspiration; and (c) annual evapotranspiration correlates significantly with annual precipitation, in contrast to the constancy of annual evaporation in catchments of wet, colder climates. Finally, a simple expression is proposed in order to calculate annual actual evaporation from the ratio of precipitation to potential evapotranspiration. This expression uses a derived exponent, k, which takes into account the characteristics of individual catchments.</style></abstract><notes><style face="normal" font="default" size="100%">doi: 10.1080/02626669109492492</style></notes><research-notes><style face="normal" font="default" size="100%">doi: 10.1080/02626669109492492</style></research-notes></record></records></xml>