Species diversity in Eucalyptus camaldulensis woodlots and miombo woodland in Northeastern Zimbabwe

The tree species diversity, groundvegetation species richness, and soilcharacteristics were studied forEucalyptus camaldulensis woodlots and thenatural miombo woodlands in the Mukarakate Areaof Northeastern Zimbabwe. The woodlandcharacteristics were measured and soil sampleswere taken at a total of thirty-four miombowoodland plots and twenty-seven eucalyptusplantations.The number of tree species was significantlyhigher for the miombo woodland sites than forthe eucalyptus woodlots. The Berger-Parker andShannon-Wiener Index values for speciesdiversity were higher for the tree speciesfound on the miombo woodland sites. There wereno significant differences between theeucalyptus woodlots and the miombo woodlands inthe percentage of grass cover and the number ofgrass and herb species. The same grass and herbspecies were common in both the woodlots andthe woodlands. The older woodlots hadsignificantly more tree and herb species thanthe younger woodlots.Soil nutrient analyses showed no significantdifferences between the woodlots and thewoodlands regarding their available phosphorusand total nitrogen, but the total phosphorusand total carbon were higher for the miombowoodlands. The results suggest that E.camaldulensis woodlots established in areasthat were formerly fields and grazing areas inthe savannah-like conditions pertaining inSouthern Africa do not cause the loss ofspecies richness or soil nutrients. In heavilydeforested areas eucalyptus woodlots may evencontribute positively to the protection andpreservation of indigenous trees species andother flora.