Properties of salt affected soil under Eucalyptus camaldulensis plantation in field conditions.

摘要

Plantation of salt tolerant trees on salt affected land is an environmental friendly and economically viable strategy to live with salinity where groundwater is also highly saline. We studied growth response of Eucalyptus camaldulensis on salt affected land and its impact on soil pH, electrical conductivity (EC), sodium adsorption ratio (SAR), organic matter contents and infiltration rate. Two sites (Chak No. 37/GB and Chak No.74/GB) in Satiana, Faisalabad, Pakistan, were selected with varying levels of natural salinity. Eucalyptus seedlings were grown on both sites for three years. A wide variation exhibited in growth of Eucalyptus plants at each site. Sixteen plants were randomly selected on each site on the basis of visual growth differences. Among these selected trees, eight were categorized as good and the other eight as poor plants. Growth parameters, such as plant height, tree girth and numbers of branches were recorded to monitor the effect of salinity on plant growth. Soil samples under the canopy of selected plants were collected up to the depth of 90 cm and analysed for EC, SAR, pH, organic matter contents and infiltration rate. Growth of Eucalyptus plants at both sites was significantly affected by salinity as compared with other plantations grown on other fields (visual observation). All growth parameters were significantly more in good plants at both sites compared to poor plants. Sodium and chloride concentration was significantly more with lower K:Na ratio in poor plants than in good ones. Amelioration of salt affected soil by Eucalyptus plantation was assessed by comparing the soil chemical and physical properties before plantation and after three years. The soil pH was quite lower in soil under good trees than in soil under poor trees at all depths and at both sites. SAR of soil under good plants at both sites was quite lower when sampled under the canopy of poor plants.