Air Pollution during Phase-I and Phase-II of Odd-Even scheme in Delhi

35-41The latest WMO estimate shows that 13 of 20 most polluted cities in the world are in India, including the worst ranked city, Delhi. For the past couple of years, the level of pollutants in this city has been 3-4 times above the safe standards. The Hon’ble Supreme Court of India has directed the policy makers to take suitable steps to bring down the level of pollution to the safe standard. For reducing the pollution level, the Government of Delhi has taken several steps; one was vehicle rationing for the period 1-15 January 2016 and 15-30 April 2016. In this program, vehicles whose number end in odd like 1, 3, 5, 7, 9 were allowed to ply on odd days, i.e 1, 3 January etc. and vehicles whose numbers end in even like 0, 2, 4, 6, 8 were allowed to ply on even days, i.e 2, 4 January etc. Sundays were exempted. In this short communication, we are reporting the pollution level of Delhi during these two periods. The average values of PM2.5 and PM10 (particulate matter) during these periods were 205 µg/m3 and 326 µg/m3, respectively, during 1-15 January and 96 µg/m3 and 179 µg/m3 during 15-30 April which were much higher than the safe limit 60 and 100 µg/m3. There was an increase in the pollution level during the event fortnight compared to the pervious fortnight which decreased in the next fortnight. The average values of surface ozone during phase-I and phase-II were 24 ppb (parts per billion by volume) and 46 ppb against the safe limit of 180 ppb. During phase-I, PM2.5, PM10 and O3 showed a decreasing trend and during phase-II they show an increasing trend. We have also examined the effect of wind, humidity and temperature on pollution level. Pollutants do not appear to have been much affected by temperature and humidity, but their trend is in phase with the wind speed. Results are presented here.</span

Surface ozone scenario at Pune and Delhi during the decade of 1990s

Data on surface ozone concentration compiled for a 10-year period from 1990 to 1999 for Pune and Delhi are analyzed in terms of its frequency distribution, annual trend, diurnal variation and its relation with various meteorological and chemical parameters. It is found that the surface ozone concentration range showing highest frequency of occurrence at Pune is 0-5 ppb during winter and post-monsoon seasons and 15-20 ppb and 5-10 ppb during summer and monsoon seasons, respectively. It is 0-5 ppb at Delhi during all the seasons. The surface ozone concentration has shown a decreasing trend at Pune during the observational period with an average rate of decrease of 1.54 ppb/year. On the other hand, there is no trend whatsoever in the variation of surface ozone concentration at Delhi. Minimum value of surface ozone occurs before sunrise and maximum in the afternoon hours. Regression analyses of surface ozone with maximum temperature (r = 0.46 for Pune and 0.51 for Delhi, significant at more than 0.1) and NO 2 at respective locations indicate that surface ozone at these locations is mainly produced by photochemistry. Transport mechanism is also understood to have contributed significantly to the total concentration of ozone. Inverse relationship obtained between surface ozone concentration and relative humidity indicates that major photochemical paths for removal of ozone become effective when humidity increases at these locations

First time observation of latitudinal and vertical distribution of infra-red radiative flux using radiometer sonde over Indian Ocean during the INDOEX IFP-1999 and its comparison with other Indian stations

Latitudinal distribution of radiative flux at different layers has been measured for the first time over the Indian Ocean from 15&#176;N to 20&#176;S during intensive field phase of INDOEX 1999. Simultaneously measurements have been made over three Indian ground stations, viz. Delhi, Pune and Trivandrum. The basic feature of radiative flux over the Indian Ocean, Delhi, Pune and Trivandrum is similar, i.e. the radiative flux increases with altitude and reaches a maximum value at 15 km and after that the increasing rate slows down. The most striking feature of this observation is the existence of radiative flux between 12 and 15 km of height near the equator (1.75&#176;N, 62.98&#176;E) which may be due to the combined effect of partly cloudy sky, presence of aerosol and ozone. In addition, at 13.3&#176;N, 60.5&#176;E a similar feature has been observed at a height of 14–15 km, which may be due to the increment of ozone by 25 Dobson Unit (D.U.) during the onward journey since no aerosol was observed. During the return journey, at 12&#176;S, 60.4&#176;E global warming is also observed at a height of 13–15 km, which may also be due to the combined effect of partly cloudy sky and the presence of aerosol and increment of ozone

Coupled Information Diffusion–Pest Dynamics Models Predict Delayed Benefits of Farmer Cooperation in Pest Management Programs

Worldwide, the theory and practice of agricultural extension system have been dominated for almost half a century by Rogers' “diffusion of innovation theory”. In particular, the success of integrated pest management (IPM) extension programs depends on the effectiveness of IPM information diffusion from trained farmers to other farmers, an important assumption which underpins funding from development organizations. Here we developed an innovative approach through an agent-based model (ABM) combining social (diffusion theory) and biological (pest population dynamics) models to study the role of cooperation among small-scale farmers to share IPM information for controlling an invasive pest. The model was implemented with field data, including learning processes and control efficiency, from large scale surveys in the Ecuadorian Andes. Our results predict that although cooperation had short-term costs for individual farmers, it paid in the long run as it decreased pest infestation at the community scale. However, the slow learning process placed restrictions on the knowledge that could be generated within farmer communities over time, giving rise to natural lags in IPM diffusion and applications. We further showed that if individuals learn from others about the benefits of early prevention of new pests, then educational effort may have a sustainable long-run impact. Consistent with models of information diffusion theory, our results demonstrate how an integrated approach combining ecological and social systems would help better predict the success of IPM programs. This approach has potential beyond pest management as it could be applied to any resource management program seeking to spread innovations across populations

Can volatile organic metabolites be used to simultaneously assess microbial and mite contamination level in cereal grains and coffee beans?

A novel approach based on headspace solid-phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC×GC-ToFMS) was developed for the simultaneous screening of microbial and mite contamination level in cereals and coffee beans. The proposed approach emerges as a powerful tool for the rapid assessment of the microbial contamination level (ca. 70 min versus ca. 72 to 120 h for bacteria and fungi, respectively, using conventional plate counts), and mite contamination (ca. 70 min versus ca. 24 h). A full-factorial design was performed for optimization of the SPME experimental parameters. The methodology was applied to three types of rice (rough, brown, and white rice), oat, wheat, and green and roasted coffee beans. Simultaneously, microbiological analysis of the samples (total aerobic microorganisms, moulds, and yeasts) was performed by conventional plate counts. A set of 54 volatile markers was selected among all the compounds detected by GC×GC-ToFMS. Principal Component Analysis (PCA) was applied in order to establish a relationship between potential volatile markers and the level of microbial contamination. Methylbenzene, 3-octanone, 2-nonanone, 2-methyl-3-pentanol, 1-octen-3-ol, and 2-hexanone were associated to samples with higher microbial contamination level, especially in rough rice. Moreover, oat exhibited a high GC peak area of 2-hydroxy-6-methylbenzaldehyde, a sexual and alarm pheromone for adult mites, which in the other matrices appeared as a trace component. The number of mites detected in oat grains was correlated to the GC peak area of the pheromone. The HS-SPME/GC×GC-ToFMS methodology can be regarded as the basis for the development of a rapid and versatile method that can be applied in industry to the simultaneous assessment the level of microbiological contamination and for detection of mites in cereals grains and coffee beans

Methemoglobinemia in aluminium phosphide poisoning in rats

95-97Aluminium phosphide (AlP) a grain fumigant is the leading cause of intentional poisoning in North India. The mechanisms involved in toxicity are not known and there is no antidote till date. The present study was carried out to investigate the oxygen free radical generation, methemoglobinemia and effect of methylene blue treatment on survival time in rat model of AlP poisoning. AlP (50 mg/kg, intragastric) was administered in one group and the other group received AlP+Methylene Blue (MB) (0.1 %, 1 mg/kg/5 min, IV). Malonyldialdehyde (MDA) and methemoglobin (MeHb) levels were measured at 10 and 30 min intervals. Blood MDA levels increased at 10 and 30 min after AlP exposure with simultaneous rise in MeHb levels suggesting methemoglobinemia could be due to increased oxygen free radical generation. Methylene blue caused a significant fall in both the parameters with prolongation of survival time. It is concluded that AlP causes methemoglobinemia responding to methylene blue treatment

Global warming and solar anomaly

391-396During 2002-2008, there was no increase in global temperature, though green house gas concentrations had increased. Sun is the ultimate source of energy. It has been, therefore, examined if there was any anomaly in the solar characteristics during this period. The sunspot number data has been used for this purpose. This parameter has an 11-year solar activity cycle and the same is found in the global temperature. But the trend in sun’s output, after removing solar activity effect, does not match with the long term trend of global temperature. Peculiarities in the duration and in the peak value of solar cycle 23 were identified which might have portended the increase of global temperature during 2002-2008. The possibility of the pause of increase in temperature could also be that the heat generated due to the increase in the greenhouse gas concentration was absorbed in deep ocean layer