Measurement of soil compaction tolerance of Lagestromia speciosa (L.) Pers. using chlorophyll fluorescence

Trees planted along roadsides and on public recreation areas are subjected to environmental stresses such as poor soil, air pollution and heat. However, very little information is available on the trees' tolerance to the various stress factors faced in an urban environment in Malaysia, such as soil compaction. The effects of soil compaction on a range of chlorophyll fluorescence parameters (F0,Fm,Fv/Fm) in foliar tissue of Lagestromia speciosa, a widely planted Malaysian street tree, were examined. Results showed that soil compaction was between 170 and 315 MPa in the study areas. Soil compaction above 180 MPa affected tree form and reduced chlorophyll fluorescence. It is concluded that chlorophyll fluorescence offers a rapid screening technique for assessing soil compaction tolerance of L. speciosa.