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Microbial Food-borne Diseases Due to Climate Change
Published in Javid A. Parray, Suhaib A. Bandh, Nowsheen Shameem, Climate Change and Microbes, 2022
John Mohd War, Anees Un Nisa, Abdul Hamid Wani, Mohd Yaqub Bhat
In summary, changing climate is affecting the whole life on planet earth. Although much attention was given to its impacts on macrobiome, its effects on microbiome is also being studied now. Microorganisms are an important part of the planet earth particularly to human life.They are present in all ecosystems and display an immense role in every type of habitat. The roles of microorganisms include: producers, decomposers, mutualists, biocontrol agents, pathogens, key contributors of biogeo-chemical cycling, role in sewage and wastewater treatment, some produce natural plant stimulants and many other important functions in maintaining ecological equilibrium of the planet earth. However, due to complexity of microbiomes, their response to changing climate is poorly understood (Bardgett et al., 2008; Zhou et al., 2012). To understand their response, it is necessary to identify the climate-sensitive microorganisms and understand their relationship with the factors responsible for the changing climate. So, various studies were conducted by many researchers to study their relations with the changing climatic variables, for example, Rui et al. (2015) studied the impact of changing climatic factors on bacterial communities of meadow soils in alpine areas. Changes in the environmental conditions due to changing climate are likely to influence all aspects of microorganism’s life. Soil microbial communities get affected by changing climatic variables either directly or indirectly through alterations in the plant physiological processes and composition of plant communities (Bardgett et al., 2013).
Drought and Dust Management
Published in Saeid Eslamian, Faezeh Eslamian, Handbook of Drought and Water Scarcity, 2017
Alireza Aghaei, Saeid Eslamian, Nicolas R. Dalezios, Ali Saeidi-Rizi, Sivash Bahredar
A classification has been developed [15] of the most important feedback mechanisms that have been proposed as responsible for land degradation by several desertification theories. These mechanisms alter the properties of soils, transform the relationship between vegetation and climate, and modify the composition of plant communities. According to this classification scheme, the following three major processes of land degradation are distinguished: (1) the loss of nutrient-rich topsoil due to wind and water erosion; (2) the decrease in soil water storage capacity induced by various causes, including unsustainable agricultural practices and overgrazing; and (3) the accumulation of salts or other toxic substances in the soil. Other authors [19] particularly focused on the important distinction between factors and causes of land degradation. Based on this the factors are biophysical processes and attributes that define the type of degradation processes, such as soil erosion, salinization, soil sealing, etc., while the causes are considered as biophysical, socioeconomic, and political agents affecting the rate of land degradation. A comprehensive study carried out by the European Union (EU) research project DESIRE (www.desire-project.eu) has shown that in 17 study sites located in the Mediterranean and Eastern Europe, Latin America, Africa, and Asia, the main processes or causes of land degradation and desertification identified in these study sites were (1) soil erosion, including water and tillage erosion; (2) soil salinization; (3) water stress; (4) forest fires; and (5) overgrazing.
Integrated management of urban aquatic habitats to enhance quality of life and environment in cities: Selected case studies
Published in Iwona Wagner, Jiri Marsalek, Pascal Breil, Aquatic Habitats in Sustainable Urban Water Management, 2014
Willows and native plant communities were tested for their efficiency in preventing the release of toxic substances and heavy metals from the Ner River and its floodplain. Pilot experiments evaluating growth rate and heavy metal uptake and their effect on the groundwater level showed that phytotoremediation measures could be optimized by an ecohydrological adjustment of the vegetation to hydrological characteristics (e.g., groundwater level) of the valley. The observed difference in the growth rate and biomass yield in the first year varied twenty times depending on tested varieties (see Figure 9.11.a). This result shows how important it is to implement a careful adaptation of a plant species to local hydrological conditions in order to optimize the produced biomass yield and, consequently, income from bioenergy. In general, the most favourable conditions were achieved at an average groundwater level lower than 0.4 measured from the ground level, while the growth rate at the initial stage depended on shallow and stable water levels. On the other hand, the efficiency of the phytoremediation process depended on heavy metals availability for plants and increased in anoxic conditions of high groundwater levels. Therefore, the remediation potential was determined by a combination of the growth rate and the availability of heavy metals to plants (see Figure 9.11.b). The regulation of groundwater levels or the selection of proper plant communities may be then a tool for optimizing plantation efficiency for either remediation of bioenergy production. Using native plant communities can help in the restoration of biodiversity and ecological values of the river and its valley.
Floristic surveys of hydrocarbon-polluted sites in some Cameroonian cities (Central Africa)
Published in International Journal of Phytoremediation, 2018
Matsodoum Nguemte Pulchérie, Suzanne II Nina Gregoire Ndemba Etim, Guy Valerie Djumyom Wafo, Pierre François Djocgoue, Ives Magloire Kengne Noumsi, Adrien Wanko Ngnien
Sorensen index was greater than 50% (K = 56.62%) when control and polluted sites were compared in all the cities surveyed, showing a similarity in flora between these two types of sites. However, Sorensen index was lower than 50% between control and polluted sites in Douala (K = 39.58%); Limbe (K = 40.42%) and Yaounde (K = 37.5%); contrary to Kribi (K = 50.74%). Local environmental conditions (temperature, drainage, nature of soils and gas emissions) could be the main factors explaining the difference or similarity in plant communities between polluted and control sites (Nagendra et al. 2006). The floristic similarity observed between the polluted and control sites of the 4 cities could have resulted from the simultaneous presence of ruderals on these sites (Messou et al. 2013).
Floristic surveys of some lowlands polluted of a tropical urban area: the case of Yaounde, Cameroon
Published in International Journal of Phytoremediation, 2021
Ayo Anne, Soh Kengne Ebenezer, Djumyom Wafo Guy Valerie, Nbendah Pierre, Djomo Chimi Cédric, Nana Annie Stephanie, Djocgoué Pierre François, Kengne Noumsi Ives Magloire (In memorium)
Sorensen’s index value obtained when compared all the polluted sites and control was too lower than 50% (K = 7.9%) indicates that plant communities are different and there is no similarity in the flora between the two types of sites investigated. This trend was also observed between each polluted site and the control where K < 12 except in site 3 (Nkolbisson lake) where K reaches 21.4%. This can be the result of the local environmental conditions (temperature, drainage, nature of soils grazing, cutting, and compaction) which could be the main factors explaining the difference or similarity in plant communities between polluted and control sites (Zhang et al. 2017).
Ecological restoration of eroded karst utilizing pioneer moss and vascular plant species with selection based on vegetation diversity and underlying soil chemistry
Published in International Journal of Phytoremediation, 2018
J. C. Shen, Z. H. Zhang, R. Liu, Z. H. Wang
Soil formation results from the combined effects of climate, vegetation, topography, substrate material and the process of soil formation changes constantly with vegetation succession (Kang et al. 2010). To a certain extent, a positive succession of plant communities contributes to the process of continuous accumulation of soil nutrients and improvement in soil physical properties; a reversal in succession of plant communities leads to the process of soil degradation (Kang et al. 2010). Complex communities of soil microorganisms with a diversity of functions play a key role in ecosystems, and their activity can provide a good measure of improvement in soil quality. This study determined that microorganisms are negatively affected by extreme rocky diversification and that there are significant differences between microorganisms associated with soil underlying mosses, and microorganisms in soil underlying vascular plants (p < 0.05). Soil is an important habitat for microorganisms, and their metabolic activities can change both physical and chemical soil properties as well as promote the conversion of matter into energy. Therefore, soil microorganisms are essential in the process of improvement of soil fertility. In areas of soil erosion areas, MBC in soil from 1 to 15 cm deep is significantly higher below mosses than below herbs, shrubs or trees. In other words, soil underlying mosses in areas of soil erosion where the soil layer is comparatively thin and relatively infertile appears to provide a more suitable habitat for microorganisms than soil underlying vascular plants. Many consider that soil under herbaceous plants is the most favorable environment for microorganisms (Johansson 1995; Grayston and Campbell 1996; Jiang, Lian et al. 2014), but these findings are inconsistent with this current study where soil under mosses was determined to be the most favorable habitat. Soil structure, water and nutrient status all have important impacts on soil microorganisms (Fierer et al. 2003). Soil erosion presents different challenges: restricted root systems and limited water storage capacity impede survival of microorganisms. Mosses have the potential to increase the soil clay and fine sand content by continuous erosion of underlying limestone rock and by capture and storage of grit and dust, from both windborne sources and from water runoff across rock surfaces (Martinez et al. 2006; Zhao et al. 2006; Zhou et al. 2014). Mosses enhance the water holding capacity of soil biological soil crusts (Duan et al. 2004; Issa et al. 2009) and improve the nutrient status of surface soil (Ayres et al. 2006; Zhao et al. 2006). Metabolites produced by living mosses and organic matter from dead mosses are beneficial to microorganisms (Singh et al. 1972; Li and Zhang 2009; Zhang, Zhang et al. 2010), providing both a favorable environment and an energy source.