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441.
Sanjiv Kumar Venkatesh Merwade 《Journal of the American Water Resources Association》2009,45(5):1179-1196
Abstract: Impact of watershed subdivision and soil data resolution on Soil Water Assessment Tool (SWAT) model calibration and parameter uncertainty is investigated by creating 24 different watershed model configurations for two study areas in northern Indiana. SWAT autocalibration tool is used to calibrate 14 parameters for simulating seven years of daily streamflow records. Calibrated parameter sets are found to be different for all 24 watershed configurations, however in terms of calibrated model output, their effect is minimal. In some cases, autocalibration is followed by manual calibration to correct for low flows, which were underestimated during autocalibration. In addition to normal validation using four years of streamflow data for each calibrated parameter set, cross‐validation (using a calibrated parameter set from one model configuration to validate observations using another configuration) is performed to investigate the effect of different model configurations on streamflow prediction. Results show that streamflow output during cross‐validation is not affected, thus highlighting the non‐unique nature of calibrated parameters in hydrologic modeling. Finally, parameter uncertainty is investigated by extracting good parameter sets during the autocalibration process. Parameter uncertainty analysis suggests that significant parameters show very narrow range of uncertainty across different watershed configurations compared with nonsignificant parameters. Results from recalibration of some configurations using only six significant parameters were comparable to that from calibration using 14 parameters, suggesting that including fewer significant parameters could reduce the uncertainty arising from model parameters, and also expedite the calibration process. 相似文献
442.
Madhumita Das Ashwani Kumar 《Environmental science and pollution research international》2009,16(4):466-473
Background, aim, and scope
High-quality waters are steadily retreating worldwide. Discharge of industrial effluent in the environment again declines soil/water quality to a great extent. On the other hand, effluent reuse in agriculture could be a means to conserve natural resources by providing assured water supply for growing crops. But industrial effluents are highly variable in nature, containing a variety of substances, and all are not favorable for farming. Appraisal and developing modes of effluent reuse is therefore a prerequisite to enable its proper use in agriculture. Effluents of various industries were assessed and approaches for their use in farming were developed for a particular region in this study. As per availability of effluents, the same could be implemented in other water-scarce areas. 相似文献443.
Agroforestry in the Western Ghats (WG) of peninsular India and satoyama in rural Japan are traditional land-use systems with
similar evolutionary trajectories. Some of their relevance was lost by the middle of the twentieth century, when modern agricultural
technologies and urbanisation engineered shifts in emphasis towards maximising crop production. There has been, however, a
resurgence of interest in traditional land-use systems recently, in view of their ability to provide ecosystem services. Both
agroforestry and satoyama are thought to be harbingers of biological diversity and have the potential to serve as “carbon
forests.” Carbon (C) stock estimates of the sampled homegardens in WG ranged from 16 to 36 Mg ha−1. Satoyama woodlands owing to variations in tree stocking and management conditions indicated widely varying C stocks (2–279 Mg ha−1). Agroforestry and satoyama also differ in nature, complexity, and objectives. While agroforestry involves key productive
and protective functions, and adopts ‘intensive management’, the satoyama woodlands are extensively managed; understorey production
is seldom a consideration. Differences in canopy architecture (multi-tiered structure of agroforestry vs. the more or less
unitary canopy of satoayama) and land ownership pattern (privately owned/managed agroforestry holdings vs. community or local
government or privately owned and mostly abandoned satoyamas) pose other challenges in the transfer and application of knowledge
gained in one system to the other. Nonetheless, lessons learnt from satoyama conservation may be suitable for common pool
resource management elsewhere in Asia, and aspects relating to understorey production in agroforestry may be relevant for
satoyama under certain scenarios. 相似文献
444.
A hybrid approach using ISM and fuzzy TOPSIS for the selection of reverse logistics provider 总被引:5,自引:0,他引:5
Govindan Kannan Shaligram Pokharel P. Sasi Kumar 《Resources, Conservation and Recycling》2009,54(1):28-36
Return of used products is becoming an important logistics activity due to government legislation and increasing awareness among the people to protect the environment and reduce waste. For industries, the management of return flow usually requires a specialized infrastructure with special information systems for tracking and dedicated equipment for the processing of returns. Therefore, industries are turning to third-party reverse logistics providers (3PRLPs). In this study, a multi-criteria group decision-making (MCGDM) model in fuzzy environment is developed to guide the selection process of best 3PRLP. The interactions among the criteria are also analyzed before arriving at a decision for the selection of 3PRLP from among 15 alternatives. The analysis is done through Interpretive Structural Modeling (ISM) and fuzzy technique for order preference by similarity to ideal solution (TOPSIS). Finally the effectiveness of the model is illustrated using a case study on battery manufacturing industry in India. 相似文献
445.
446.
The magnetic properties of tree leaves along with their ecological, economical and aesthetic importance can be used to control
road derived respirable particulates. Isothermal remanent magnetization (IRM300 mT) of three different tree leaves viz. Mango (Mangifera indica), Sisso (Dalbergia sisso) and Banyan (Ficus benghalensis) were determined and IRM300 mT normalized for the leaf area. The normalized 2-D magnetization of leaves as shown by results is dominantly controlled
by leaf morphology and traffic density. F. benghalensis (Banyan) leaf has highest 2-D magnetization and D. sisso (Sisso) leaf having least 2-D magnetization suggesting greater ability of F. benghalensis (Banyan) tree leaves to reduce magnetic particulates. The particle size of the magnetic grains falls in the category of PM2.5,
a particle size hazardous to human health due to its capacity to be inhaled deeply into the lungs. 相似文献
447.
Dynamics of traffic noise in a tropical city Varanasi and its abatement through vegetation 总被引:1,自引:0,他引:1
Noise level monitoring and its reduction with different width and height of vegetation belt were studied in the Varanasi city. Noise level monitoring of the Varanasi city revealed the fact that area category A (without vegetation) was highly polluted as compare to area category B (with vegetation) having less fluctuation of traffic load. Four plant species Putranjeva roxburghi, Cestrum nocturnum, Hibiscus rosasinensis and Murraya peniculata were tested for noise reduction study at different frequencies. Experiment revealed the fact that H. rosasinensis reduced noise highest at both low and high frequencies (100-500 Hz, 22 dB and 2.5-6.3 KHz 26 dB), followed by M. peniculata (100-500 Hz, 18 dB and 2.5-6.3 KHz 20 dB), P. roxburghi (100-500 Hz 15 dB and 2.5-6.3 KHz 17 dB) and C. nocturnum (100-500 Hz 9 dB and 2.5-6.3 KHz 14 dB). Significance of vegetation belt in noise reduction was established with multiple regression models. 相似文献
448.
The study to generate the baseline of natural radiation and radioactivity in East and West Khasi Hills District of Meghalaya, India was conducted to determine the different radiation dose in selected stations. Twenty stations were selected in both the district, which include Shillong the capital of Meghalaya and the Domiasiat area, which has been identified as one with a Uranium ore deposit. The dose was measured using a Micro-R-Survey meter and from the measurement it was found out that the absorbed dose in both the districts ranges from 0.04 to 1.66 microGy h(-1). The maximum dose was observed in Kylleng (0.72 microGy h(-1)) and the minimum in Mawphlang (0.06 microGy h(-1)). Average absorbed dose and equivalent dose were found to be higher than the Indian and world average values by several orders. The radiation levels distribution was found to be non-uniform through out the selected study area. 相似文献
449.
Hydrochemistry of surface water (pH, specific conductance, total dissolved solids, sulfate, chloride, nitrate, bicarbonate, hardness, calcium, magnesium, sodium, potassium) in the Mahanadi river estuarine system, India was used to assess the quality of water for agricultural purposes. The samples were studied for 31 different stations during six different seasons in the years 2001-2003. Chemical data were used for mathematical calculations (SAR, Na%, RSC, potential salinity, permeability index, Kelly's index, magnesium hazard, osmotic pressure and salt index) for better understanding the suitability river water quality for agricultural purposes. The river water is free from nitrate-nitrogen hazard and has much less osmotic pressure and RSC values. Further there is no complete precipitation of calcium and magnesium in the study area. The results revealed that waters of some polluted stations like Sambalpur down (D/s of Sambalpur town) and Kathjodi (Cuttack) down (D/s of Cuttack town) are unsuitable up to some extent, where as it is quite unsuitable in case of estuarine samples during the pre-monsoon and post-monsoon seasons. The results were verified by USSL and Wilcox diagrams, which show all the fresh water zone samples (low-medium salinity with low sodium) of the study area are in the 'Excellent to good' category and are suitable to irrigate all soils for semi-tolerant and tolerant as well as sensitive crops. 相似文献
450.
Chatterjee M Massolo S Sarkar SK Bhattacharya AK Bhattacharya BD Satpathy KK Saha S 《Environmental monitoring and assessment》2009,150(1-4):307-322
This paper presents a comprehensive account regarding concentration, distribution and possible sources of trace elements (Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn) in 20-30 cm sediment cores (<63 microm particle size) collected at the confluence of the Ganges River and Bay of Bengal (Sunderban wetland, India). This work aims to evaluate the fluvio-marine and geochemical processes influencing the metal distribution. The most interesting features are the downward increase of concentrations of majority of the elements reaching overall maximum values at a depth of 10-15 cm observed in station Lot No.8 located along the main stream of the Ganges estuary as well as an overall elevated concentration of all the elements in the lower littoral zone. The interelemental relationship revealed the identical behaviour of elements during its transport in the estuarine environment. The overall variation in concentration can be attributed to differential discharge of effluents originating from industrial and agricultural as well as from domestic sewage. Arsenic exceeded effects range - low (ER - L) concentrations, implying occasional or frequent adverse biological effects. For Cu, Ni and Cr a smaller proportion of samples had exceeded the ER - L values indicating that the dataset would be suitable for future use in evaluating predictive abilities of SQGs. 相似文献