• Journal of Ginseng Research
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• v.39 no.1
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• pp.81-88
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• 2015

Background: In Changbai Mountains, Panax ginseng (ginseng) was cultivated in a mixture of the humus and albic horizons of albic luvisol in a raised garden with plastic shade. This study aimed to evaluate the impact of ginseng planting on soil characteristics. Methods: The mixed-bed soils were seasonally collected at intervals of 0-5 cm, 5-10 cm, and 10-15 cm for different-aged ginsengs. Soil physico-chemical characteristics were studied using general methods. Aluminum was extracted from the soil solids with $NH_4Cl $(exchangeable Al) and Na-pyrophosphate (organic Al) and was measured with an atomic absorption spectrophotometer. Results: A remarkable decrease in the pH, concentrations of exchangeable calcium, $NH_4^+$, total organic carbon (TOC), and organic Al, as well as a pronounced increase in the bulk density were observed in the different-aged ginseng soils from one spring to the next. The decrease in pH in the ginseng soils was positively correlated with the $NH_4^+$ (r=0.463, p<0.01), exchangeable calcium (r=0.325, p<0.01) and TOC (r= 0.292, p < 0.05) concentrations. The $NO_3^-$ showed remarkable surface accumulation (0-5 cm) in the summer and even more in the autumn but declined considerably the next spring. The exchangeable Al fluctuated from $0.10mg\;g^{-1}$ to $0.50mg\;g^{-1}$ for dry soils, which was positively correlated with the $NO_3^-$ (r=0.401, p < 0.01) and negatively correlated with the TOC (r=-0.329, p < 0.05). The Al saturation varied from 10% to 41% and was higher in the summer and autumn, especially in the 0-5 cmand 5-10 cm layers. Conclusion: Taken together, our study revealed a seasonal shift in soil characteristics in ginseng beds with plastic shade.