Plant communities and potential native phytoremediator species in
petroleum hydrocarbon-polluted desert systems
Abstract
This paper reported the recovery of desert plant communities after
twenty years of oil-derived hydrocarbon contamination in desert habitats
of Kuwait, caused by the First Gulf War (1990 – 1991). The hypothesis
that certain native desert plant species can tolerate weathered
oil-polluted soils with oil breakdown products (i.e., polycyclic
aromatic hydrocarbons ( PAHs)) and have the potential to function as
bioindicators and phytoremediator species for oil-polluted soil was
tested. A field survey of 200 quadrat sampling plots at seven
hydrocarbon-contaminated and unpolluted desert areas in Kuwait was
performed that recorded 42 plant species, with Haloxylon salicornicum,
Cyperus conglomeratus and Rhanterium epapposum as the most dominant
species. Analysis of plant tissues indicated plant uptake and
accumulation of some PAHs. H. salicornicum was used as a representative
species in a controlled field study that included growth of plants in
hydrocarbon-polluted and unpolluted soils in two separate desert areas
under similar growth conditions. Results showed a significant decrease
in plant biomass in oil-contaminated soil compared to those from the
uncontaminated site. However, the plants appeared green and healthy in
both sites, and showed no overt stress. The results suggest that some
desert plant communities exhibit signs of recovery after severe oil
pollution, and that H. salicornicum may serve as a phytoremediator of
oil-contaminated desert soils. Our results also demonstrated that some
desert plant communities could be cultivated in oil fields to reduce
hydrocarbon contamination and provide guide to other ecosystem services
through improving soil quality and biodiversity.