The large-scale expansion of rubber plantations in southern India: major impacts and the changing nature of drivers.

This study investigates the major environmental and socio-economic impacts of an increase in the area of rubber plantations and the changing patterns of drivers of land use changes. Using a combination of geospatial techniques and socio-economic methods, we mainly analyzed the rate of increase in area under rubber plantations, the major impacts of land use changes, and the changing drivers of land use changes. Our results show that the area under rubber plantations has increased significantly within the study area, with the area under rubber plantations increasing from 30 to 74% of the total area within five decades. Impact assessment of land use changes based on household surveys showed significant improvement in the socio-economic conditions of the farmers, however, at the expense of severe environmental degradation. Our results also indicate that while areas under rubber plantations continue to increase, the drivers of land use changes have changed over time. Furthermore, it has been observed that in the past, many interventions prioritized social and economic development and placed less emphasis on the ecological stability of the region. Perceptions of farmers revealed that the effects of ecological fragility already affected the economic robustness of the whole area. Therefore, we conclude that government interventions to support additional rubber cultivation should also focus on ecosystem stabilization in order to minimize the risk of an ecological catastrophe that would significantly affect the economic prosperity of the region.

Biodegradation of aromatic hydrocarbons using microbial adsorbed bioreactor.

Polyurethane (PU) tubular coil-based bioreactor was constructed and evaluated for the effective biodegradation of benzene, toluene, xylene and phenol (BTXP). Herein, the removal of BTXP was done with a formulated bacterial consortium adsorbed on the inner surface of the PU coil. The formulated consortium consisted of four bacterial strains namely, Alcaligenes sp. d 2 , Enterobacter aerogenes, Raoultella sp. and Bacillus megaterium. The adsorption ability of the bacterial cells onto the coil surface was assessed by spectrophotometric and Scanning Electron Microscopic (SEM) analysis. BTXP degradation performance was evaluated by Ultra-Violet spectroscopy and the degradation was confirmed by Fourier Transform Infrared Spectroscopy (FT/IR). The bioreactor constructed using polyurethane (PU) tubular coil with adsorbed bacterial cells exhibited 70% degradation capacity of 250 µL of 5% benzene, toluene, xylene and phenol (BTXP) at a pH of 6 within 8 h of treatment. FT/IR spectra of the treated sample indicated the production of ketonic, carboxylic acid/esters during biodegradation. The innovative technology proposed in the current study with the formulated bacterial consortium and the novel bioreactor opens up new possibilities for the better removal of BTXP mixture from contaminated sites and industrial effluents.