phase frontphase soilphenomenaphenomenonphereatic risephotographic barographphotospherephotothermal unitphreatic fluctuationphreatic linephreatic surfacephreatic waterphyllosilicate mineralsphysical climatologyphysical lifephysical propertiesphysical weatheringphytomorphic soilpiecewisepierpier extensionpier froude numberpier shapepiezomertic headpiezometerpin meter programpinhole testpipe flowpipingpiptot sphere pipepiracy riverpit runpitot pipepittingpixelplacic horizonplaggen epipedonplanationplanetary atmosphereplanetary windsplanimeterplanit consumptionplanned grazing systemplanosolsplant coverplant layout modelplant residueplanting basinplanting limitplaque forming unit