Investigating the enzyme activities and physicochemical properties of soil in the habitat of Prosopis cineraria (L.) Druce and P. juliflora (SW.) DC.

Changes due to the introduction of non-native species are very important, especially in arid and desert areas. Because protection and regeneration in these fragile ecosystems are difficult. Soil is the basis of ecosystems. The effect of introduction and establishment of non-native species can be evaluated by sensitive indicators such as soil enzyme activities. The activity of acid and alkaline phosphatase, urease, dehydrogenase, and invertase enzymes were investigated as well as soil physicochemical properties (the percentage of soil moisture, organic carbon, total nitrogen and available phosphorus) under and outside the canopy of Prosopis cineraria (L.) Druce and P. juliflora (SW.) DC.). Soil sampling (in total, 24 samples) was done randomly from a depth of 0-30 cm in a natural habitat of the two species located in Assaluyeh, Bushehr province, Iran. The statistical analysis showed the sampling location had a significant effect on activities of the all studied enzymes (p< at least 0.05). These enzymes were more active under the canopy of the sample trees. Under the canopy of P. juliflora, enzyme activities did not differ significantly from that of P. cineraria. The interaction of species and sampling location was only significant in alkaline phosphatase enzyme activity (p<0.01). Due to the lack of harmful effects of P. juliflora as a non-native species on soil enzymes activities and also it's a very fast growth, it seems that with the application of scientific and correct management, P. juliflora in de-desertification and forest regeneration programs in Sahara-Sindhi habitats in Assaluyeh should be noticed.