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Integrated water resources management (IWRM) is being implemented all over the world, considering its wide area of applications and flexible spatial scale. Scientists have found IWRM useful in an Indian context also where a coordinated development of water and land resources is sought as part of complete economic, social and environmental welfare. The paper presents the concepts of ‘Local IWRM’ planning applied to water conservation and management in a case study of Ur river watershed in Tikamgarh district of Madhya Pradesh (India). The Plan considers effective utilization of land, water and other available natural resources, linked to the vulnerabilities and livelihood opportunities in the geographical area. The IWRM Plan, designed in three sections – (1) water management, (2) land management, and (3) livelihood management – provides specific suggestions on the activities under these three themes as useful inputs to the District Irrigation Plan (DIP) of the Government. The proposed IWRM Plan intends to promote the component of water demand management in district level planning and is envisioned to be an ‘implementable’ planning document for district level government. Acceptability of the IWRM plan is potentially enhanced as the plan was developed through a participatory process, wherein all relevant stakeholders were consulted at different stages of development.

This study examined the potential of the aquatic macrophyte Eichhornia crassipes for bioaccumulating hexavalent chromium and its effects on the plant's morphology. The macrophytes were exposed to different concentrations of Cr (VI) (0 -100 mg L -1 ) in 20% full-strength Hoagland nutrient solution for ten days. Changes in the Cr (VI) concentrations were measured in the media and in specific plant tissues, i.e., roots, shoot, and leaves. The bioconcentration factor (BCF) in all plant parts and the translocation factor (TF) within plant tissues were calculated twice during the experiment. Results demonstrated that E. crassipes accumulated high concentrations of Cr (VI) in all plant tissues examined in a dose-specific manner. High BCF was observed in the plant roots for concentrations up to 60 mg L -1 , after which accumulation in shoots and leaves were greater than roots. The results from E. crassipes survivorship indicated that 40 mg L -1 is the threshold concentration for their survival under Cr (VI) stress. Morphological changes in the plants were examined by monitoring the change in the number of leaves and plant height under varying Cr (VI) concentrations. Impeded growth was observed due to increasing Cr (VI) concentration with maximum growth in the control group with no Cr (VI). Evapotranspiration losses were monitored and found to be minimal in experimental groups with high concentrations, displaying a negative correlation with Cr (VI) contamination. Physico-chemical parameters including pH, Electrical Conductivity, Oxidation Reduction Potential, and colour were also found to be significantly correlated with Cr (VI) concentration and time. The results demonstrated significant Cr (VI) accumulation in E. crassipes as well as noticeable morphological changes, making E. crassipes a suitable organism for biomonitoring and remediating Cr-contaminated sites over a relatively short time-period.

Nanoscale zerovalent iron (nZVI) was synthesized and employed for treating chromium (VI) containing aqueous solution through adsorption using a series of microcosm experiments. The experiments were then performed to study the effects of a light non-aqueous phase liquid (LNAPL), toluene, on Cr (VI) removal by nZVI. Results showed that a maximum removal efficiency of almost 90% was achieved within 300 minutes of the treatment process, while it was suppressed by ~25% in toluene's co-presence. The efficiency was found higher (>80%) at pH 3-7 and reduced to 30.3% at pH 9. No significant change in the removal was observed due to change in pH under toluene's co-presence (57-65% removal for all pH ranges). The removal efficiency also reduced from 62.7% to 37.1% and 82.1 to 28.3% with increase in Cr (VI) concentration (25 to 200 mg/L), with and without co-existing toluene, respectively. Surface morphology and structure of nZVI pre-and post-treatment with Cr (VI) and toluene was analyzed through scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy.The results confirmed the presence of Cr (VI) and toluene on the nZVI surface. The adsorption of Cr (VI) by nZVI was best described by pseudo second order (PSO) kinetics (R 2 = 0.97 in both the cases) and Langmuir isotherm equilibrium model (R 2 = 0.95, 0.81). The maximum adsorption capacity (Qmax) for Cr (VI) without and with toluene was 64.52 mg/g and 58.47 mg/g of the nZVI particles, respectively. Findings from this study provide crucial information about co-contamination and its noticeable effects on remediation of the contaminants of concern.

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