THE INFLUENCE OF FIVE NATIVE TREE SPECIES ON SOIL CHEMISTRY IN A SUBTROPICAL HUMID FOREST REGION OF ARGENTINA

Abstract

The effects of five native tree species on the chemical characteristics of soil were studied. The species were from Misiones Province, Argentina: Balfourodendron riedelianum, Bastardiopsis densiflora, Cordia trichotoma, Enterolobium contortisiliquum and Ocotea puberula. Adjacent areas free of trees were used as controls. Results from the two-way ANOVA showed the importance of C, N and Ca as key elements that may be influenced by soil cover and depth. The highest total soil carbon and nitrogen contents were found under the crowns of Bastardiopsis densiflora, C. trichotoma and E. contortisiliquum. The soil pH values were highest under B. densiflora and C. trichotoma in the first 15 cm of soil depth while that under B. riedelianum was the lowest, including that of the control site. Bastardiopsis densiflora, C. trichotoma and E. contortisiliquum had the highest sum of bases in the first 15 cm of soil depth. Extractable calcium under the canopy of Bastardiopsis densiflora and C. trichotoma was significantly different from that of control plots up to 30 cm in soil depth. Soil magnesium content under the crowns of E. contortisiliquum was significantly different from that of the control up to 30 cm depth. Significant differences for potassium were found up to 15 cm in depth below B. densiflora, C. trichotoma and E. contortisiliquum. Of the species studied, B. densiflora showed the greatest promise for use in rehabilitation of degraded lands.