시설재배지 토양 pH와 전함량 및 이동태 함량이 상추의 구리와 아연 흡수에 미치는 영향

Abstract

Copper and Zinc are essential trace elements for all living organisms. When presenting in excess amount in soils, however they can be toxic to plants. In order to examine the transfer of Cu and Zn from soils to plants and to predict their contents in plants using soil factors, we investigated total and mobile contents of Cu and Zn in soils and their uptake by lettuce (Lactuca sativa L.) in plastic film houses. Total Cu and Zn contents in soils were 17.5∼65.9 mg kg -1 (mean: 39.3 mg kg -1 ) and 63.2∼200 mg kg -1 (mean: 137 mg kg -1 ), respectively. Mobile Cu and Zn contents in soils were (0.04)∼0.55 mg kg -1 (mean: 0.18 mg kg -1 ) and (0.05)∼2.62 mg kg -1 (mean: 0.47 mg kg -1 ), respectively. Soil pH ranged from 5.4 to 7.3 and OM from 24.1 to 59.9 g kg -1 . Mean Cu contents in leaves and roots of lettuce were 9.20 and 17.2 mg kg -1 , respectively which showed that Cu was accumulated mainly in root parts of lettuce and not easily transported to leaves. In contrast, Zn was fairly evenly distributed in leaves and roots with mean values of 54.5 and 56.7 mg kg -1 , indicating relative high mobility of Zn in lettuce. Transfer factors of Cu and Zn from soil total contents to roots and leaves of lettuce (TFStR and TFStL) were between 0.1 and 1, while transfer factors from soil mobile contents to roots and leaves (TFSmR and TFS mL) were between 10 and 1000. Transfer factors of Zn were higher than those of Cu, showing Zn was more easily absorbed by plants than Cu. Cu and Zn uptake was stronger influenced by soil pH and mobile contents than total contents and OM and could be significantly described by multiple regression equations including soil pH and soil mobile contents as variables.