TABLE 1.

Chemical properties of Sourhope soil^a

Soil	pHb	Total organic carbon (mg g−1)c	Freundlich parameters for adsorption of 2,4-dichlorophenold
			Kf	n	KOC
Nonplanted	4.03 (0.007)	24.61 (0.80)	5.75 (1.02)	0.83 (0.006)	233.6
L. perenne rhizosphere	4.02 (0.003)	21.03 (0.51)	5.60 (1.02)	0.82 (0.007)	266.3
T. pratense rhizosphere	4.04 (0.008)	24.52 (0.71)	5.47 (1.01)	0.83 (0.005)	223.1

^aSoil was sampled from the rhizospheres of L. perenne and T. pratense after 60 days of plant growth. Values are means (standard errors), n = 4.

^bDetermined in CaCl₂ after removal of root debris.

^cDetermined by wet oxidation after removal of root debris.

^dThe concentration dependence of 2,4-dichlorophenol adsorption to L. perenne, T. pratense (with incorporated root debris), and nonplanted soil was investigated after 1 h (25°C) over triplicate initial aqueous concentrations of 0.2, 2, 10, 50, and 250 μg of [¹⁴C]2,4-dichlorophenol ml⁻¹. Data are expressed as the linear form of the Freundlich equation (r² > 0.99 in all cases), logS = logK_f + nlogA, where S is the adsorbed concentration (in micrograms per gram), A is the aqueous concentration (in micrograms per milliliter), logK_f is the intercept, and n is the elasticity of sorption. K_oc is calculated as K_f/percent total organic carbon × 100.