Impacts of Sewage Sludge in Tropical Soil: A Case Study in Brazil

Table 1

Chemical characteristics of sewage sludge utilized in experiments.

Characteristcs		First cultivation		Second cultivation		Third cultivation		Fourth cultivation		Fifth cultivation		Sixth cultivation
	Unit^(a)	BS	FS	BS	FS	BS	FS	BS	FS	BS	FS	BS	FS
Ar	mg kg^−1	<1	<1	<1	<1	<1	<1	<0.01	<0.01	<0.1	<0.1	<0.01	<0.01
Al	mg kg^−1	28,781	32,564	25,300	33,500	23,283	23,317	11,959	18,189	14230.7	21672.2	15063	30302
Cd	mg kg^−1	12.8	3.32	9.5	2.0	9.4	2.05	16.2	1.14	14.0	0.6	14.1	1
Pb	mg kg^−1	364.4	199.6	233	118	348.9	140.5	137.9	78.6	148.7	43.0	127	26.6
Cu	mg kg^−1	1058	239.8	1046	359	953.0	240.9	682.8	187.1	867.8	196.0	805	152
Cr total	mg kg^−1	823.8	633.8	1071	1325	1297.2	1230.3	609.3	202.0	639.6	182.4	700	128
Fe	mg kg^−1	54,181	33,793	32,500	31,700	37,990	24,176	39,058	39,895	32,100	64,900	31,892	77,997
Hg	mg kg^−1	<0.01	<0.01	<1	<1	<0.01	<0.01	<0.01	<0.01	<0.1	<0.1	<0.01	<0.01
Mo	mg kg^−1	<0.01	<0.01	<1	<1	<0.01	<0.01	<0.01	<0.01	<0.1	<0.1	<0.01	<0.01
Ni	mg kg^−1	518.4	54.7	483	74	605.8	72.4	331.3	63.9	270.0	49.5	253	50.7
Se	mg kg^−1	<0.01	<0.01	<1	<1	<0.01	<1	<0.01	<0.01	<0.1	<0.1	<0.01	<0.01
Zn	mg kg^−1	2821	1230	3335	1590	3372	1198	2327.9	773.0	3330.0	890.6	2888	640
B	mg kg^−1	36.2	40.7	11.2	7.1	29.3	19.7	10.7	10.4	17.6	13.6	11.1	3.2
C organic	g kg^−1	248.2	305.1	271	374	292.9	382.4	354.2	370.9	534.4	475.4	312	200
pH		6.6	6.3	6.4	6.4	6.4	5.4	8.5	8.9	8.0	8.3	8.3	7.8
Humidity^(b)	%	66.4	83	80.2	82.4	71.2	82.7	79.5	74.6	78.8	78.5	81.2	75
Volatile solids	%	43.0	60.5	—	—	56.8	72.5	62.6	67.0	59.6	58.65	62	42
N Total^(b)	g kg^−1	21	56.4	49.7	67.5	42.1	68.2	50.8	49.7	79.7	57.7	43.5	32.2
F	g kg^−1	15.9	16.0	31.2	21.3	26.9	12.9	17.7	13.8	17.9	27.3	16.1	18.3
P	g kg^−1	1.0	1.0	1.97	0.99	1.0	1.0	1.5	1.5	1.0	1.0	1.2	0.7
Na	g kg^−1	0.5	0.5	0.6	0.6	0.5	0.9	0.5	0.5	0.9	0.4	0.3	0.3
S	g kg^−1	13.4	16.3	10.8	13.3	17.1	15.7	11.7	9.3	14.5	10.1	12.6	6.5
Ca	g kg^−1	40.3	29.2	22.8	16.8	47.8	24.8	20.1	13.3	19.4	11.5	13.4	10.4
Mg	g kg^−1	3.0	2.2	3.7	2.5	4.5	2.2	3.7	2.7	3.8	5.0	2.8	1.5
Mn	mg kg^−1	429.5	349.3	335	267	418.9	232.5	277.5	439.8	246.9	712.9	209	683

Concentration values given are based on dry matter. ^(a)Determined according EPA SW-846-3051 (1986), in IAC (Campinas, São Paulo). ^(b)Concentration values for N total and humidity were determined in the sample under the original conditions, in Embrapa Environment. EPA, 1986. Test methods for evaluating solid waste, physical/chemical methods. US Environmental Protection Agency. Office of solid waste and emergency response, third ed. U.S. Government Office, Washington, DC, SW-846-3051.