p e ipackerpalahpaleoclimatepaleoclimatologypaleosolpalisadepalmer boulus flumepalmer drought severity indexpalmer hydrological drought indexpamperopanpan coefficientpannierparabola cross sectionparabolicparabolic curveparalithic contactparallel flowparameterparecipition gageparent materialparshall flumepartial areapartial droughtpartial duration seriespartial expansionpartial flow pipepartial potential temperaturepartial pressurepartially full flowpartical size analysisparticel densityparticle densityparts per millionpasspasturepasture improvementpasture plantingpasture renovationpatamic depositspatential erosionpathpavementpavingpay offpci=principal component analysispeakpeatpeat soil