000			022500000a22005770004500
911			_aXL2000500456
901			_aP35
902			_aP32
903			_aE
904			_aBCO
905			_aC
906			_a20000101
908			_aJ
909			_aAS
912			_aEn
912			_aEn
914			_aBCO
090			_aCATIE _bK19s
100	1		_982394 _aKass, D.C.L.
100			_aSomarriba, Eduardo _9120490
100	1		_988977 _aMacedo, J.L.V. de
260			_c1999
041	0		_aEn
500			_a2 fig. 5 tab. 25 ref. Sum. (En)
520			_aSince its development in 1982, a sequential extraction procedure proposed by Hedley has been used to separate soil phosphorus (P) into labile and less labile organic and inorganic components. More recently, the procedure has been used to characterize changes in soil P under agroforestry systems. However, correlation with plant response has been poor and several publications have shown that factors such as soil type, soil texture, and nutrient status can affect the size of the different fractions as much as management practices. In the present article, we examine whether depth and time of sampling can also affect the size and distribution of the P fractions and their relationship to plant response.
650	1	4	_9148494 _aFRACCIONES DEL SUELO
650	1	4	_9148453 _aFOSFORO
650	1	4	_9155490 _aMUESTREO
650	1	4	_9166804 _aTIPOS DE SUELO
650	1	4	_9166636 _aTEXTURA DEL SUELO
650	1	4	_9144675 _aDISPONIBILIDAD DE NUTRIENTES
650	1	4	_9134976 _aAGROFORESTERIA
691			_9338954 _aSOIL SEPARATES
691			_9158339 _aPHOSPHORUS
691			_9337245 _aSAMPLING
691			_9338967 _aSOIL TEXTURE
691			_9328921 _aNUTRIENT AVAILABILITY
691			_9134979 _aAGROFORESTRY
692			_aFRACTION DU SOL
692			_aPHOSPHORE
692			_aECHANTILLONNAGE
692			_aTEXTURE DU SOL
692			_aDISPONIBILITE D'ELEMENT NUTRITIF
692			_aAGROFORESTERIE
773	0		_tAgroforestry Forum (RU) _d1999 _gv. 9(4) p. 42-49
022			_a0966-8616
040			_aCR-TuBCO _cCR-TuBCO _bEs
245	1	0	_aSoil phosphorus fractions in agroforestry systems: effect of soil depth and sampling time
942			_cANA
003			CR-TuBCO
999			_c110730 _d110730