00844cas a22002777ar450000500170000000800410001701000100005801100100006802200140007803500110009224500680010326000560017130000070022731000140023432100120024836200170026065000540027765000560033178000220038786600340040986600270044386600200047086600300049086600270052086600190054720220329143037.0001017u1981    us mr p rnn   0   b1eng d  a91118  a92090  a0199-9060  a10265300aSoil and Water Conservation Newsc/by Soil Conservation Service0 aWashington, D.C.:bSoil Conservation Servicec1980.  av.  aBimestral  aMensual  av.13n.2,199214aAguaxConservaciónxPublicaciones periódicas.14aSuelosxConservaciónxPublicaciones periódicas.  tSoil conservation  av.1 n.1,3-9,11-12 (1980-1981)  av.12 n.3-7 (1991-1992)  av.13 n.2 (1993)  av.2 n.5-6,8-12 (981-1982)  av.3 n.7-12 (1982-1983)  av.4 n.2 (1983)