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61.
Mapping forest biomass is fundamental for estimating CO2 emissions, and planning and monitoring of forests and ecosystem productivity. The present study attempted to map aboveground woody biomass (AGWB) integrating forest inventory, remote sensing and geostatistical techniques, viz., direct radiometric relationships (DRR), k-nearest neighbours (k-NN) and cokriging (CoK) and to evaluate their accuracy. A part of the Timli Forest Range of Kalsi Soil and Water Conservation Division, Uttarakhand, India was selected for the present study. Stratified random sampling was used to collect biophysical data from 36 sample plots of 0.1 ha (31.62 m?×?31.62 m) size. Species-specific volumetric equations were used for calculating volume and multiplied by specific gravity to get biomass. Three forest-type density classes, viz. 10–40, 40–70 and >70 % of Shorea robusta forest and four non-forest classes were delineated using on-screen visual interpretation of IRS P6 LISS-III data of December 2012. The volume in different strata of forest-type density ranged from 189.84 to 484.36 m3 ha?1. The total growing stock of the forest was found to be 2,024,652.88 m3. The AGWB ranged from 143 to 421 Mgha?1. Spectral bands and vegetation indices were used as independent variables and biomass as dependent variable for DRR, k-NN and CoK. After validation and comparison, k-NN method of Mahalanobis distance (root mean square error (RMSE)?=?42.25 Mgha?1) was found to be the best method followed by fuzzy distance and Euclidean distance with RMSE of 44.23 and 45.13 Mgha?1 respectively. DRR was found to be the least accurate method with RMSE of 67.17 Mgha?1. The study highlighted the potential of integrating of forest inventory, remote sensing and geostatistical techniques for forest biomass mapping.  相似文献   
62.
A procedure is detailed for the selective analysis of trace aluminum by flame atomic absorption spectrophotometer coupled with off-line column separation and preconcentration. Chelating resin was synthesized by covalent functionalization of Amberlite XAD-16 by 2-(2-hydroxyphenyl) benzoxazole. The modified resin was characterized using FT-IR spectroscopy, energy dispersive x-ray analysis, elemental analysis, thermogravimetric analysis/differential thermal analysis, and minimum energy run. The optimum sorption was at pH 9?±?0.1 with corresponding t 1/2 of only 7 min. Many competitive anions and cations studied did not interfere at all in the selective determination of Al(III), at the optimized conditions. The resin shows maximum sorption capacity of 21.58 mg g?1 and can be regenerated up to 75 cycles without any discernible capacity loss. The Langmuir isotherm model provides the better correlation of the experimental data (r 2?=?0.999) in comparison to Freundlich isotherm model, while the Scatchard analysis revealed homogeneous binding sites in the chelating resin. Analytical figures of merit were evaluated by accuracy (standard reference materials and recovery experiment), precision (RSD <5 %), and detection limit (2.8 μg L?1). The applicability was demonstrated by analysis of trace aluminum in biological, environmental, and food samples.  相似文献   
63.
The present study examined the suitability of vermicomposting technology for processing source-separated human faeces. Since the earthworm species Eisenia fetida could not survive in fresh faeces, modification in the physical characteristics of faeces was necessary before earthworms could be introduced to faeces. A preliminary study with six different combinations of faeces, soil and bulking material (vermicompost) in different layers was conducted to find out the best condition for biomass growth and reproduction of earthworms. The results indicated that SVFV combination (soil, vermicompost, faeces and vermicompost – bottom to top layers) was the best for earthworm biomass growth indicating the positive role of soil layer in earthworm biomass growth. Further studies with SVFV and VFV combinations, however, showed that soil layer did not enhance vermicompost production rate. Year-long study conducted with VFV combination to assess the quality and quantity of vermicompost produced showed an average vermicompost production rate of 0.30 kg-cast/kg-worm/day. The vermicompost produced was mature as indicated by low dissolved organic carbon (2.4 ± 0.43 mg/g) and low oxygen uptake rate (0.15 ± 0.09 mg O2/g VS/h). Complete inactivation of total coliforms was noted during the study, which is one of the important objectives of human faeces processing. Results of the study thus indicated the potential of vermicomposting for processing of source-separated human faeces.  相似文献   
64.
Objective: The present study examines the accelerating and braking behaviors of drivers at different blood alcohol concentrations (BACs) in heterogeneous driving conditions using driving simulator experiments.

Methods: Eighty-two licensed drivers performed simulated driving in a rural road environment designed in the driving simulator at 4 BAC levels: 0.00, 0.03, 0.05, and 0.08%. Driving performance was analyzed using vehicle control variables such as mean acceleration and mean brake pedal force. Generalized linear mixed models were developed to quantify the effect of different alcohol levels and explanatory variables such as driver’s age, gender, and other factors on the driving performance indicators.

Results: Alcohol use was reported as a significant factor affecting the accelerating and braking performance of drivers. The acceleration model results indicated that drivers’ mean acceleration increased by 0.013, 0.026, and 0.027 m/s2 for BAC levels of 0.03, 0.05, and 0.08%, respectively. Results of the brake pedal force model showed that drivers’ mean brake pedal force increased by 1.09, 1.32, and 1.44 N for BAC levels of 0.03, 0.05, and 0.08%, respectively. Age was a significant factor in both the models where a 1-year increase in driver age resulted in a 0.2% reduction in mean acceleration and a 19% reduction in mean brake pedal force. Driving experience could compensate for the negative effects of alcohol to some extent while driving.

Conclusions: The findings of the present study revealed that drivers tend to be more aggressive and impulsive under the influence of alcohol, which deteriorates their driving performance. Impairment in accelerating and braking behaviors of drivers under the influence of alcohol leads to increased crash probabilities. The conclusions may provide reference in making countermeasures against drinking and driving and contribute to traffic safety.  相似文献   

65.
Coliphages represent a process indicator for fecal pollution. The coal bed concentration method prepared for enterovirus was refined for a concentration of coliphages. A bed made from 1.5 g of 120-mesh coal powder was used for concentrating coliphage from 200 mL of a water sample with or without the addition of aluminum chloride at different pH values. The isolated E. coli strain EC-R8 was found to be more susceptible to the desired coliphage and showed significant coliphage-coliform response, with clear plaque used for further studies. The complete coliphage adsorption was achieved with the addition of 0.0005 M AlCl3 at pH 6.0. Adsorbed coliphages were eluted with 3% beef extract in Mcllvaine buffer at pH 7.1, with an average recovery of 78.74%. This concentration technique was applied for the detection of coliphages from the well water of Nagpur city (India) and found to contain coliphages in the range of 2 to 28 plaque-forming units per liter (PFU/L).  相似文献   
66.
The coarser (CPM) and respirable (RPM) fractions of aerosol loads collected in a time sequence, during the onset of winter season in Delhi region, were subjected to Principal Component Analysis (15 elemental variables, 39 samples); the absolute mass contributed by each identified source to the CPM and RPM was quantified by using Absolute Principal Component Score (APCS) and Positive Matrix Factorization (PMF) method. Interestingly, the mass contributed by the local crustal source (material) to both fractions manifested undulating periodic behavior, a dominating harmonic corresponding to 24-h period was detected by using Discrete Fourier Transform (DFT). The corresponding harmonics, of varying strengths, were also detected in the recorded meteorological factors: Planetary Boundary Layer (PBL), Surface Level Temperature (T), Surface Level Relative Humidity (RH) and Wind Speed (WS). The analysis of the respective harmonic strength within the CPM, RPM, and meteorological factors suggested that the undulation observed in both size fractions of aerosol load from the local crust was affected by the meteorological factors. The large proportion of undulating loads (CPM and RPM), explained by the dominating harmonic, was fully accounted for by the empirical relation involving the discrete coupling parameters, and the recorded meteorological factors: PBL, T, RH and WS. The analysis suggests that the magnitude and the direction (‘positive’ load increase and ‘negative’ the reverse) of coupled meteorological factors'(s) effect on ambient CPM, RPM load is determined by the phase difference between the harmonic explaining the aerosol fraction's load and the corresponding harmonic present in the respective meteorological factor. The absolute mass contributions arising from the identified sources (APCS and PMF) allowed us to calculate the baseline ambient concentrations of undulating CPM and RPM loads, in the region of this study, affected by meteorological factors only.  相似文献   
67.
Inhalation of emissions from petrol and diesel exhaust particulates is associated with potentially severe biological effects. In the present study, polycyclic aromatic hydrocarbons (PAHs) were identified from smokes released by the automobile exhaust from petrol and diesel. Intensive sampling of unleaded petrol and diesel exhaust were done by using 800-cm3 motor car and 3,455-cm3 vehicle, respectively. The particulate phase of exhaust was collected on Whatman filter paper. Particulate matters were extracted from filter paper by using Soxhlet. PAHs were identified from particulate matter by reverse phase high performance liquid chromatography using C18 column. A total of 14 PAHs were identified in petrol and 13 in case of diesel sample after comparing to standard samples for PAH estimation. These inhalable PAHs released from diesel and petrol exhaust are known to possess mutagenic and carcinogenic activity, which may present a potential risk for the health of inhabitants.  相似文献   
68.
Forest certification has emerged as a marketing tool for linking the good forest management practices with the environmentally conscious consumers. Its genesis can be attributed to the society’s concern for the social and environmental significance of forests. Forest management certification when coupled with the chain-of-custody certification; then, the supply chain stages for such forest products can carry an ecolabel. Non-timber forest products (NTFPs) are of socio-economic and cultural importance for the forest dwelling communities, particularly for the tropical countries like India. India is home to an amazing diversity of plants, with over 46,000 plant species recorded to occur there. NTFP’s availability, utilization, commercialization, exploitation, management practices, policies and tenure systems in different parts of India have high diversity and variability. There is concern, however, that collection methods for most of NTFP species are destructive and wild populations are declining as a result. Thus, the harvest of NTFPs is coming under increasing scrutiny from certification programmes, as it plays a key role in the sustainable management of forest resources and community benefit worldwide. Thus, the present research paper highlights the issues relevant to certification of NTFPs in India, based on more than a decadal experience in dealing with this subject at Indian Institute of Forest Management, Bhopal.  相似文献   
69.
Textile mill waste can be vermicomposted if it is mixed in the range of 20–30% with cow dung. This article reports the effect of inoculation, of nitrogen fixing Azotobacter chroococcum strain; Azospirillum brasilense strain and phosphate solubilizing Pseudomonas maltophila, on nitrogen and phosphorus content of vermicomposts prepared from cow dung (CD) and cow dung spiked textile mill sludge (CD + STMS). The CD vermicompost was more supportive to the growth and multiplication of all the three bacteria than CD + STMS vermicompost. In Azotobacter chroococcum treated vermicomposts maximum nitrogen content was recorded between 45 and 60 days [CD␣vermicompost (25.9 ± 0.45 g kg−1) and CD + STMS vermicompost (20.6 ± 0.62 g kg−1)] followed by Azospirillum brasilense inoculation [CD vermicompost (19.4 ± 0.60 g kg−1) and CD + STMS vermicompost (18.6 ± 0.17 g kg−1)]. Phosphorus content in Pseudomonas maltophila inoculated CD vermicompost was 20.8 ± 0.20 g kg−1 and CD + STMS vermicompost was 13.4 ± 0.45 g kg−1 after 75th day of inoculation.  相似文献   
70.
Environmental Science and Pollution Research - The current scenario of increased population and industrial advancement leads to the spoliation of freshwater and tapper of the quality of water....  相似文献   
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