Ecophysiology of Wild Plants and Conservation Perspectives in the State of Qatar

© 2013 Yasseen and Al-Thani, licensee InTech. This is an open access chapter distributed under the term

Microbial Ecology of Qatar, the Arabian Gulf: Possible Roles of Microorganisms

The Arabian Gulf ranks among the world's most arid and warm regions; the land has high salinity levels with many Sabkhas and receives little precipitation. This region holds about one-third of the world's oil supply. Qatar is the leading gas producer worldwide, which raises many concerns about the pollution of the sea, groundwater, and soil. Thus, the Arabian Gulf area has paid particular attention to environmental studies since the environmental status of this region imposed unique biological diversity, and microbial ecology has gained special importance following the identification of promising roles of microorganisms. This review article discusses the microbial ecology at the main habitats of the State of Qatar. We discuss important principles for successful ecological restoration and future perspectives of using biological approaches to solve many problems related to health, the economy, and agriculture. There are at least five microbial communities that have been recognized at the Qatari habitats: marine environment, salt marshes and mangrove forests, the arid lands (including dune communities), wetlands (including pond communities), and Rawdahs (including the Ghaf tree communities). Although, the environmental conditions of this region are almost the same, these habitats are compared with those at other countries of the Arabian Gulf whenever necessary, as each habitat has its own peculiar characteristics. Some case studies are presented to describe the biochemical characterizations of bacterial isolates from soils and leaf surface of native plants, including halophytes and xerophytes at these habitats. These studies rarely went beyond the general identification at species levels. There is a discussion about the possible roles of microorganisms at the rhizosphere, non-rhizosphere, and phyllosphere, and using plant exudates to control microbial activity. However, modern approach (culture-independent methods) addressing these topics has opened the door for deeper investigations, and to explore the roles played by microorganisms at these habitats. These methods have already begun during the last decade as serious step to solve many environmental issues. In the future, it is very likely that microorganisms will be used to tackle many pollution issues, as well as health, agricultural, and economic problems.The authors would like to thank the Environmental Studies Center (ESC), Qatar University, for the technical and financial support of the research projects reported in this article. The authors acknowledge that the editing service was done by American Manuscript Editing; AME, Kevin.Scopu

Endophytes and Halophytes to Remediate Industrial Wastewater and Saline Soils: Perspectives from Qatar

Many halophytes are considered to be salt hyperaccumulators, adopting ion extrusion and inclusion mechanisms. Such plants, with high aboveground biomass, may play crucial roles in saline habitats, including soil desalination and phytoremediation of polluted soils and waters. These plants cause significant changes in some of the soil’s physical and chemical properties; and have proven efficient in removing heavy metals and metabolizing organic compounds from oil and gas activities. Halophytes in Qatar, such as Halopeplis perfoliata, Salicornia europaea, Salsola soda, and Tetraena qatarensis, are shown here to play significant roles in the phytoremediation of polluted soils and waters. Microorganisms associated with these halophytes (such as endophytic bacteria) might boost these plants to remediate saline and polluted soils. A significant number of these bacteria, such as Bacillus spp. and Pseudomonas spp., are reported here to play important roles in many sectors of life. We explore the mechanisms adopted by the endophytic bacteria to promote and support these halophytes in the desalination of saline soils and phytoremediation of polluted soils. The possible roles played by endophytes in different parts of native plants are given to elucidate the mechanisms of cooperation between these native plants and the associated microorganisms