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1.

This study has been focused on the efficient removal of Pb (II) from contaminated waters by biosorption using plant derived material. Accordingly an indigenous shrub, Tinospora cordifolia has been identified as the most suitable biosorbent. The plant biomass was subjected to optimization of various parameters such as the pH, equilibrium time, dosage, concentration, temperature and the applicable adsorption models. The optimum pH identified was 4.0 with a contact time of 60 min at room temperature (27 ± 2 °C). The experimental data fitted well to adsorption isotherms and the uptake capacity of Pb (II) was found to be 20.83 and 63.77 mg/g in batch mode and column mode, respectively. The high correlation factors obtained for Langmuir and Freundlich models indicated that both models were obeyed by the system. Kinetic study for adsorption of Pb (II) follow only pseudo second order rate of reaction. The accumulation of lead in biomass was confirmed by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis. The FTIR analysis indicated the involvement of hydroxyl (−OH), alkenes (=CH) and carbonyl group (C = O) chelates in metal binding. The SEM and EDX analysis showed the structural changes and the filling of voids in the biomass thus, it indicated the metal-binding mechanism. In elution studies, the 0.1 M Na2CO3 was found to be the best with about 71% elution of the adsorbed metal. The biomass was then used for the removal of Pb (II) in synthetic and real wastewater samples from a lead-acid battery industry. It is also noteworthy that even at a very high concentration of 450 mg/L, the biomass was showing about 92% removal. The result is to establish the efficacy of T. cordifolia as a very good bioadsorbent for the Pb (II) removal from contaminated water.

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This study deals with the future scope of REDD (Reduced Emissions from Deforestation and forest Degradation) and REDD+ regimes for measuring and monitoring the current state and dynamics of carbon stocks over time with integrated geospatial and field-based biomass inventory approach. Multi-temporal and multi-resolution geospatial synergic approach incorporating satellite sensors from moderate to high resolution with stratified random sampling design is used. The inventory process involves a continuous forest inventory to facilitate the quantification of possible CO2 reductions over time using statistical up-scaling procedures on various levels. The combined approach was applied on a regional scale taking Himachal Pradesh (India), as a case study, with a hierarchy of forest strata representing the forest structure found in India. Biophysical modeling implemented revealed power regression model as the best fit (R 2?=?0.82) to model the relationship between Normalized Difference Vegetation Index and biomass which was further implemented to calculate multi-temporal above ground biomass and carbon sequestration. The calculated value of net carbon sequestered by the forests totaled to 11.52 million tons (Mt) over the period of 20 years at the rate of 0.58 Mt per year since 1990 while CO2 equivalent reduced from the environment by the forests under study during 20 years comes to 42.26 Mt in the study area.  相似文献   
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The state of human-environment (ecosystems) interactions—ecosystems (land cover classes), population, biodiversity hotspots and protected status—is examined in the eastern coastal zones, the eastern region, the middle region, the western region and the whole of China. The analysis is based on consistent, comprehensive, geo-referenced and recent datasets and advanced analytical Remote Sensing and Geographic Information System (GIS) techniques. A comparative national and regional priority ranking of the provinces was conducted using the total score of eight indicators, for the four dimensions of human-environment (ecosystems) interaction. Using, these ranks, all the provinces were grouped in low, high and medium priority provinces. The comparative ranking and categorization of provinces will be useful for designing policies and management operations for spatially-differential scientific planning and management of environment (ecosystems) at the regional and national levels in China.  相似文献   
5.
Can development occur without running down natural resources in an unsustainable way? The concept of natural capital offers a way for those with divergent views (ecologists and economists for example) to discuss this difficult question. Four aspects are examined in detail. First, the role of institutions in facilitating sustainable development is discussed, with examples from forestry. Then examples from (eco)tourism illustrate the potential – and limits – of applicability of the concept. Measurement issues for natural capital are then considered in detail. Finally, the concept is applied to agricultural strategy in fragile lands, where the tradeoff between the environment and development is likely to be most severe. Some implications for future research and policy are developed.  相似文献   
6.
New institutional economists have argued that there are many categories of institutions, including market and non-market institutions, which may prove economically efficient, specifically for public goods and common pool goods. The Government of India introduced a non-market community-based institution, known as Joint Forest Management (JFM), for forest management and protection in 1990. JFM is a sharing mechanism for forest planning and management based on sharing of rights and duties, control and decision-making authority over forestlands, between forest departments and local user groups. By 2001, 42 000 Village Forest Committees established under JFM were managing over 11.5 million ha forestland. These institutions have proved very useful, and have contributed to forest management as well as four aspects of sustainable human development (SHD) – ecological output, income generation, village infrastructure development, and community empowerment. In the long-term, community-based institutions will prove to be a foundation of SHD and participatory democracy.  相似文献   
7.
Acute toxicity and presumable harmless concentration of two commercial insecticides, Furadan 3G and Malataf 50E were reported for tubificid worms, Tubifex tubifex and Limnodrilus hoffmeisteri. L. hoffmeisteri were found more susceptible to both the insecticides; the Furadan was found to be more toxic than Malataf to tubificid worms. Analysis of variants showed a significant difference between safe concentrations of the same insecticide to different species.  相似文献   
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Environment, Development and Sustainability - Our society faces mounting pressure regarding the necessity of green consumption as issues related to the environment will likely become a severe...  相似文献   
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Environmental Science and Pollution Research -  相似文献   
10.
1-(4-Chlorophenyl))-N-hydroxymethanimine and cyclohexyl-N-hydroxymethanimine were synthesized and a well-established oxime, i.e., 2-[(hydroxyimino)methyl]-1-methylpyridinium chloride was purchased. Thereafter; all were loaded over Al2O3 using incipient wetness technique. The prepared systems were characterized using surface area analyzer, scanning electron microscope, energy dispersive X-ray spectrophotometer, Fourier transform infrared spectrophotometer and thermogravimetric analyzer. Kinetics of the degradation of sarin (GB) and simulant, i.e. diethylchlorophosphate (DEClP) was studied over synthesized oxime impregnated Al2O3 and results were compared with well reported oxime impregnated Al2O3. Kinetics of reaction was found to be following the pseudo first order reaction kinetics. The order of reactivity of the prepared systems was found to be cyclohexyl-N-hydroxymethanimine/Al2O3 > 1-(4-chlorophenyl)-N-hydroxymethanimine/Al2O3 > 2-[(hydroxyimino)methyl]-1-methylpyridinium chloride/Al2O3 > Al2O3. From the reaction kinetics it was observed that the reaction with DEClP was faster than with GB. Cyclohexyl-N-hydroxymethanimine/Al2O3 was found to be the most reactive system with half-life of 0.94 and 15 h for DEClP and GB respectively.  相似文献   
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