dilution methoddilution ratiodimensiondimensionless curvedimensionless hydrographdimensionless unit hydrographdimple springdinitrogen fixationdioctahydraldioctahydral sheetdioritedipdirec cost of conservationdirect approachdirect bank protectiondirect integration methoddirect jumpdirect precipitationdirect protectiondirect runoffdirect runoff hydrographdirect shear testdirect solar radiationdirect step methoddirected graphdisaggregationdischargedischarge areadischarge capacitydischarge carrierdischarge coefficientdischarge correction coefficientdischarge efficiencydischarge head relationdischarge hydrographdischarge measurementdischarge of the overflowdischarge ratedischarge rating curvedischarge velocitydischrge hydographdiscontinousdiscontinous flowdiscontinuity in flow profilediscontinuous gullydiscrete l or 2 normdiscretizationdisintegrationdismembered streamdispersion