Author(s)

A. Hassan, Z. Taqi, C. Obuekwe & E. Al-Saleh

Abstract

The planning of cities must insure a balance between human consumption and natural resources that should be preserved and if needed should be used minimally and efficiently following plans of sustainability. The current study investigated the possibility of recycling natural waste product \“plants leaves” that usually fall off, are collected, dumped and burnt. In counties like Kuwait where crude oil constitutes a major pollutant and the environment is hostile for microbial activity rendering bioremediation to be a trivial option. Thus, in the present study, the leaves of Conocarpus and Tamarix were used to enrich the low organic content soils that showed the potential of soil supplementation with organic matter to enhance the growth and activity of soil indigenous microbiota. The amendments of soils with 20 mg g-1 soil significantly increased the counts of crude oil-degrading bacteria in crude oil-contaminated and uncontaminated soils to 999.4 x 10-3 CFU g-1 and 358.8 x 10-3 CFU g-1soil, respectively. The identification of isolated bacteria revealed the dominance of the genus Microbacterium (39.6%), Sphingopyxis soli (19.3%), and Bordetella petrii (19.6%) in unamended, Conocarpus-amended and Tamarix-amended contaminated soils, respectively. The 16S rRNA analyses showed the high diversity of isolated bacteria. Also, the diversity of the majority of isolated bacteria decreased after soil amendments with plant-derived material. Therefore, the recycling of plant-derived materials could be an excellent option under conditions tested and confirm the commandments of sustainable planning. Keywords: bioremediation, Conocarpus, Tamarix, crude oil-degrading bacteria, Microbacterium, Sphingopyxis, 16S rDNA, amendments.

Keywords

bioremediation, Conocarpus, Tamarix, crude oil-degrading bacteria, Microbacterium, Sphingopyxis, 16S rDNA, amendments