Author/Authors :
Masahide Aikawa، نويسنده , , Takatoshi Hiraki، نويسنده , , Motonori Tamaki، نويسنده , , Mitsuru Shoga، نويسنده ,
Abstract :
In order to clarify the limitations and the effectiveness of filtering-type bulk sampler, a study on precipitation collected by filtering-type bulk and wet-only samplers was performed. At an urban site, there was a statistically significant difference between the filtering-type bulk and wet-only samples at a 1% significance level in the pH and major chemical components. At a suburban site, pH, NH4+, and nss-Ca2+ showed a difference at a 1% significance level and NO3− at a 5% significance level, but nss-SO42− did not show any difference even at a 5% significance level. At a rural site, although there was a difference in nss-Ca2+ at a 1% significance level and in pH at a 5% significance level, nss-SO42−, NO3−, and NH4+ did not show any difference. The attributions of the deposition of gaseous compounds and particulate matter in a filtering-type bulk sampler were estimated to be 32% (nss-SO42−), 46% (NO3−), 36% (NH4+), and 75% (nss-Ca2+) at an urban site, 14% (nss-SO42−), 16% (NO3−), 27% (NH4+), and 42% (nss-Ca2+) at a suburban site, and 16% (nss-SO42−), 17% (NO3−), 19% (NH4+), and 47% (nss-Ca2+) at a rural site. The degree of pollution at a sampling site should be taken into account when using a data set collected with filtering-type bulk samplers.
Keywords :
Wet-only sampler , Site classification , Filtering-type bulk sampler , Acid precipitation , z-Tests