Wet‐only sequential deposition in a rural area in north‐eastern Spain     

ANDRÉS ALASTUEY  XAVIER QUEROL  AURA CHAVES  ANGEL LOPEZ&#;SOLER  CARMEN R. RUIZ 《Tellus. Series B, Chemical and physical meteorology》2001,53(1):40-52

The present work summarises the results of a 2‐year study of wet‐only sequential deposition in 2 rural areas (Alcan¯iz and Morella) located at different distances from a large coal‐fired power station. Precipitation chemistry was characterised by relatively high , Ca²⁺ and average concentrations. Sequential study of single precipitation events showed that concentrations of most of the ions studied decreased exponentially throughout single precipitation events, with a sharper decrease in concentrations at the beginning of the event. Usually, 40 to 80% of the wet‐only deposition of major ions occurred in the first 2 mm. pH measurements, ranging from 5.6 to 8.1, showed a decrease in the pH values throughout a precipitation event. Deposition levels of Ca²⁺ and accounted for the neutralisation of major acidic species in the precipitation events except in 5 rain episodes sampled at Morella. The sequential study of the evolution of the ratio during a single precipitation allowed us to identify potential acidic rainfall fractions after an initial volume of precipitation, after most of the Ca²⁺ in atmospheric particles had been scavenged. A higher neutralisation capacity was deduced for Alcan¯iz owing to the higher atmospheric levels of natural carbonates and .  相似文献