Food security and dietary diversity of tea workers of two tea gardens in greater Sylhet district of Bangladesh

The study analyzed the food security and dietary diversity of tea workers in Lakkatura Tea Garden and Ootterbhag Tea garden in greater Sylhet district of Bangladesh. A total of 200 respondents (100 from each tea estate) were interviewed to evaluate the food security and dietary diversity. The study found that average daily per capita calorie intake by tea workers was 2095.96 kcal. In addition, around 85.30% of the total calorie intake was received from the rice consumption. Average per capita daily intake of rice was estimated at 538.51 gm which is higher than the national average. It was also observed that 71.7 and 65.0% households were food secure in Lakkatura and Ootterbhag Tea garden, respectively. In Lakkatura Tea Garden, 61.67% tea workers have medium dietary diversity and in Ootterbhag Tea Estate 49.47% tea workers have low dietary diversity. Using the logit model analysis, this study provides food consumption patterns of tea workers and determine the factors responsible for food security. Household size, farm income and daily calorie intake were found having significant influence on households’ food security. For improving socioeconomic conditions of tea workers, educational institution should be set up to improve their educational status and government should give loans for them at a low interest rate and create alternative job opportunity in off season.

     

Comparison of tropical and midlatitude thunderstorm characteristics anchored in thermodynamic and dynamic aspects

Thunderstorms prevailing over tropics and midlatitudes depict dissimilar features relating to the thermodynamic and dynamic aspects. The identification of the physical characteristics of the tropical and midlatitude thunderstorms is the main objective of the present study. The stations Kolkata (22.6°N, 88.4°E) and Denver (39.47°N, 104.32°W) are selected from the tropics and midlatitudes for the comparative analyses. The study reveals that the average storm relative helicity (SRH) and the lapse rate between 700 and 500 hPa level is much higher over Denver compared to Kolkata during thunderstorm days. The study further reveals that the surface to mid troposphere (upto 500 hPa) become drier (～2 times) over Denver than Kolkata prior to the occurrence of thunderstorms while the upper tropospheric (300–100 hPa) humidity remains comparable for both the locations.     

Estimation of Biomass Heat Storage Using Thermal Infrared Imagery: Application to a Walnut Orchard

A new method to estimate tree biomass heat storage from thermal infrared (TIR) imaging of biomass surface temperature is presented. TIR images of the canopy are classified into trunk, branches, and leaves. The one-dimensional heat equation in cylindrical coordinates is forced with trunk and branch surface temperatures to simulate the temperature distribution and heat storage in tree trunks and branches. Assuming uniform leaf temperatures, heat storage in leaves is computed from the surface temperature of the leaves separately for the sunlit upper and shaded lower canopy. The sum of trunk, branches, leaf, and air heat storage gives the canopy heat storage. Measurements in a walnut orchard near Davis, California, in early June 2007 showed that biomass heat storage was of the same order as air heat storage and about 1% of daytime and 9% of nighttime net radiation.     

Hydrometeorological Aspects of Floods in India

The Indian sub-continent being located in the heart of the summermonsoon belt, receives in most parts more than 75% of its annual rainfall during the fourmonsoon months of June to September. As the bulk of summer monsoon rainfall occurs withina period of four months, naturally majority of floods occur in Indian rivers during thisseason only. The ground conditions also help in generating high percentage of run-offbecause of the antecedent wet conditions caused by rainy spells occurring within the monsoonperiod itself. Besides mentioning different weather systems, which cause heavy rainfall and consequentfloods, a detailed discussion of 15 years' floods in different river systems has alsobeen given in the article. This study has shown that the flood problem in India is mostly confinedto the states located in the Indo-Gangetic plains, northeast India and occasionally in therivers of Central India.     

Velocity of small-scale auroral ionospheric current systems over Indian Antarctic station Maitri

The Indian Antarctic station Maitri (geog. 70‡45’S, 11‡45’E, geom. 66‡.03S, 53‡.21E) occupies a sub-auroral location during magnetically quiet conditions(Σκρ < 10), but attains an auroral position when the auroral oval shifts equatorwards with increasing strength of magnetic disturbance. At the latter times, triangulation with 3 fluxgate magnetometers located at the vertices of a suitable triangle provides a means of monitoring mobile auroral ionospheric current systems over Maitri. The spacing between the magnetometers is typically kept at 75–200 km, keeping in mind the scale-sizes of ∼ 100 km for these mobile current systems. This work reports the results of two triangulation experiments carried out around Maitri in January 1992 and January 1995, both during Antarctic summer. The velocities estimated for pulsations of the Pc4 and Pc5 type were about 0.59 km/sec in the direction 102‡.7 east of due north, in the first case, and about 1–3 km/sec in the second case in the east-west direction. While several magnetometer arrays exist in the northern auroral regions (e.g., the Alberta array in Canada, the Alaskan array in the U.S. and the IMS Scandinavian array), there is no report in literature of triangulation through arrays in Antarctica, except for a one-day study by Neudegget al 1995 for ULF pulsations of the Pc1 and Pc2 type. The velocities obtained for the Pi3 type of irregular pulsations over Antarctica in the present study tally well with those obtained for northern auroral locations.     

On some characteristics of severe rainstorms of India

Summary Detailed examination of daily rainfall data for India (and other relevant publications regarding severe rainstorms) show that during the last 110 years, the Indian region recorded 231 severe rainstorms. Of these, 27 were of 2-day duration and the rest (204) were of 3-day duration. Within a rainstorm, maximum rain fell on the 2nd day on 63% of occasions. It was also observed that the average raindepths obtained from slow moving rainstorms were greater in magnitude than those of fast moving rainstorms. All these rainstorms, during their movement through the country, had their rain centres at about 308 locations. This study has shown that only 19 locations recorded severe rainstorm centres on five or more occasions. Maximum number of rain centres recorded for one location was 13.With 2 Figures     

Envelope Depth-Area-Duration raindepths for different homogeneous rainstorm zones of the Indian region

Summary About one hundred severe rainstorms occurred in the Indian region during the period between 1880 and 1990. The centres of these severe rainstorms occur mostly in four preferred zones. The two major zones where the bulk of rainstorm centres are located are in north and central India. These two zones have been further sub-divided into four homogeneous subzones for the purpose of rainstorm transposition. For each of these homogeneous sub-zones and zones envelope Depth-Area-Duration (DAD) raindepths have been calculated. These are based on the DAD data of severe rainstorms that have occurred within each zone in order to obtain probable maximum precipitation (PMP) estimates.With 4 Figures     

Hydrological modelling of the Kangsabati river under changed climate scenario: case study in India

India is a large developing country with nearly two‐thirds of the population depending directly on the climate‐sensitive sectors such as agriculture, fisheries and forests. A very well‐calibrated Soil and Water Assessment Tool (R² = 0·9968, NSE = 0·91) was exercised over the Kangsabati river watershed in Bankura district of West Bengal, India, for a year including monsoon and non‐monsoon period in order to evaluate projected parameters for agricultural activities. Evapotranspiration, transmission losses, potential evapotranspiration and lateral flow to reach are evaluated from the years 2041–2050 in order to generate a picture for sustainable development of the river basin and its inhabitants. The projected climate change under various scenarios is likely to have implications on food production, water supply, biodiversity and livelihoods. India has a significant stake in scientific advancement as well as an international understanding to promote mitigation and adaptation. This requires improved scientific understanding, capacity building, networking and broad consultation processes. This paper is a commitment towards the planning, management and development of the water resources of the Kangsabati river by presenting detailed future scenarios of the Kangsabati river basin over the mentioned time period. The major findings of this paper were that of all the chosen projected parameters, transmission losses, soil water content, potential evapotranspiration, evapotranspiration and lateral flow to reach, display an increasing trend over the time period of years 2041–2050. Copyright © 2009 John Wiley & Sons, Ltd.     

Geochemical and hydrogeological contrasts between shallow and deeper aquifers in two villages of Araihazar, Bangladesh: Implications for deeper aquifers as drinking water sources

Sediment and groundwater profiles were compared in two villages of Bangladesh to understand the geochemical and hydrogeological factors that regulate dissolved As concentrations in groundwater. In both villages, fine-grained sediment layers separate shallow aquifers (< 28 m) high in As from deeper aquifers (40-90 m) containing < 10 μg/L As. In one village (Dari), radiocarbon dating indicates deposition of the deeper aquifer sediments > 50 ka ago and a groundwater age of thousands of years. In the other village (Bay), the sediment is < 20 ka old down to 90 m and the deeper aquifer groundwater is younger, on the order of hundreds of years. The shallow aquifers in both villages that are high in As contain bomb-³H and bomb-¹⁴C, indicating recent recharge. The major and minor ion compositions of the shallow and deeper aquifers also differ significantly. Deeper aquifer water is of the Na⁺-HCO₃^- type, with relatively little dissolved NH₄⁺ (76 ± 192 μmol/L), Fe (27 ± 43 μmol/L) and Mn (3 ± 2 μmol/L). In contrast, shallow aquifer water is of the Ca²⁺-Mg²⁺-HCO₃^- type, with elevated concentrations of dissolved NH₄⁺ (306 ± 355 μmol/L), Fe (191 ± 73 μmol/L), and Mn (27 ± 43 μmol/L). In both villages, the quantity of As extractable from deeper aquifer sands with a 1 mol/L phosphate solution (0.2 ± 0.3 mg/kg, n = 12; 0.1 ± 0.1 mg/kg, n = 5) is 1 order of magnitude lower than P-extractable As from shallow deposits (1.7 ± 1.2 mg/kg, n = 9; 1.4 ± 2.0 mg/kg, n = 11). The differences suggest that the concentration of P-extractable As in the sediment is a factor controlling the concentration of As in groundwater. Low P-extractable As levels are observed in both deeper aquifers that are low in As, even though there is a large difference in the time of deposition of these aquifers in the two villages. The geochemical data and hydrographs presented in this study suggest that both Holocene and Pleistocene deeper aquifers that are low in As should be a viable source of drinking water as long as withdrawals do not exceed recharge rates of ∼1 cm/yr.     

Greatest observed one-day point and areal rainfall of India

The greatest one-day rain amounts recorded at individual stations in the country during the last 41-year period from 1940 onwards were examined for all observatories as well as State rain-gauge stations in an attempt to bring out up-to-date information on the greatest recorded point rainfall for the duration of one day. Outstanding one-day point rainfall amounts recorded prior to 1940 were also examined and have been included in this note along with their date and year of occurrence by way of comparison. A generalized chart has been prepared based on the percentage ratios of the greatest one-day rainfall to the mean annual rainfall of about 300 observatory stations distributed uniformly over the entire country. On the basis of Depth-Area-Duration (DAD) analyses of the most severe rainstorms which occurred over different plain areas of the country, it has been found that the 2 July, 1941, rainstorm gave the highest areal rain depths in the country for different areas. Comparison with similar areal rain depths of the tropical USA has shown that rain depths of the July, 1941, rainstorm were higher for all areas excepting the areas of 500 sq. miles (1295 sq. km) and 1000 sq. miles (2590 sq. km).