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91.
Pinki Mondal Meha Jain Andrew W. Robertson Gillian L. Galford Christopher Small Ruth S. DeFries 《Climatic change》2014,126(1-2):61-76
India is predicted to be one of the most vulnerable agricultural regions to future climate changes. Here, we examined the sensitivity of winter cropping systems to inter-annual climate variability in a local market and subsistence-based agricultural system in central India, a data-rich validation site, in order to identify the climate parameters to which winter crops – mainly wheat and pulses in this region – might be sensitive in the future. We used satellite time-series data to quantify inter-annual variability in multiple climate parameters and in winter crop cover, agricultural census data to quantify irrigation, and field observations to identify locations for specific crop types. We developed three mixed-effect models (250 m to 1 km scale) to identify correlations between crop cover (wheat and pulses) and twenty-two climate and environmental parameters for 2001-2013. We find that winter daytime mean temperature (November–January) is the most significant factor affecting winter crops, irrespective of crop type, and is negatively associated with winter crop cover. With pronounced winter warming projected in the coming decades, effective adaptation by smallholder farmers in similar landscapes would require additional strategies, such as access to fine-scale temperature forecasts and heat-tolerant winter crop varieties. 相似文献
92.
RETRACTED ARTICLE: Development prospects of groundwater resources in an elliptical shape island,Union Territory of Lakshadweep,India 总被引:1,自引:1,他引:0
A major problem of the islanders is the availability of fresh water for drinking purpose. Groundwater is the only source of fresh water for the islanders. The demand for groundwater is increasing very year due to growing population and urbanization. A proper understanding of the groundwater condition is important in order to meet this increasing demand and to formulate future development and management strategies. It is in this context, principal hydrogeologic units; water table fluctuation pattern, general groundwater potential, existing groundwater withdrawal structures and draft, water quality, etc. have been studied in an elliptical shape Andrott Island of Union Territory of Lakshadweep, India, through field investigation and secondary data collection. Groundwater occurs under phreatic condition and seawater is in hydraulic continuity with the groundwater as evidenced by the tidal influence in almost all the wells. Groundwater level fluctuation due to seasonal variation varies from 0 to 0.542 m depending on the distance of the well from the coast. Depth to groundwater level varies from less than 1.234 to 3.520 m depending on the topography. Groundwater level fluctuation is due to the combination of factors like rainfall, tidal activities, sub-surface runoff, and draft. Large diameter dug wells are the main groundwater extraction structures in this island. There are 2,143 dug wells with almost each family having its own well and the density of the dug wells is about 437/km2. The stage of groundwater development is estimated as 37% and hence “Safe” for further groundwater development in this island. However, considering the very limited fresh-water resources and also the growing demand for groundwater, various management strategies such as rainwater harvesting, artificial recharge of groundwater, public participation in water conservation and wise use of groundwater, etc., have been suggested. 相似文献
93.
94.
Seismicity along the Himalayan front is mostly attributed to the processes of collision between the Indian and the Eurasian
plates resulting in the under-thrusting of the Indian Peninsula underneath the Himalaya. The dynamics of the region bears
very complex components which require in-depth understanding. Here the overall rate of crustal shortening since ∼ 11 Ma is
∼ 21mm/yr, which is comparable to modern rate of under-thrusting of the northern Indian plate beneath the Himalaya. The region
experienced a large number of great earthquakes for the last 100–120 years causing massive destruction. Here an attempt has
been made to understand the seismicity pattern of the region using fractal correlation dimension and hence used for the detection
of active seismicity. Some clusters of seismicity were found to be indicative of seismically very active zones. Such clusters
may enlighten the understanding of recent complex dynamics of Himalayan zone. 相似文献
95.
Rain height in relation to 0°C isotherm height for satellite communication over the Indian Subcontinent 总被引:1,自引:0,他引:1
Summary ¶The 0°C isotherm height, a parameter needed for the estimation of attenuation of microwave and millimetre wave for earth-space communication, has been estimated for different stations spread over India. The variations of 0°C isotherm height for different seasons over these stations are presented. Attenuations of radio wave due to rain at frequencies 10GHz and above have also been estimated for few stations using the 0°C isotherm height so derived. The results are useful for radio systems designers. 相似文献
96.
Use of hydrochemical parameters for the identification of fresh groundwater resources,Potharlanka Island,India 总被引:2,自引:0,他引:2
V.?K.?SaxenaEmail author V.?S.?Singh N.?C.?Mondal S.?C.?Jain 《Environmental Geology》2003,44(5):516-521
A hydrochemical study has been carried out on the fresh groundwater resources of Potharlanka, Krishna Delta, India. Groundwater samples were collected at 58 sites and analyzed in June and December 2001. The groundwater is mildly alkaline with a pH of 7.2–8.2, electrical conductivity (EC) varies from 645–4,700 µS/cm in June 2001 (pre-monsoon) and from 605–5,770 µS/cm in December 2001 (post-monsoon). More than 75% of the samples have >1000 mg/l TDS which is higher than the maximum permissible limit for potable water. Na and Cl are the dominating cations and these are directly proportional to TDS. Extremely low HCO 3/Cl and variable high Mg/Ca (molar ratios) indicated the transformation of the fresh groundwater aquifer systems to saline. Groundwater of this island is classified as Na–Cl, Na–Ca–Cl–HCO 3, Na–Mg–Cl–SO 4 and mixed types. A high percentage of mixed water types indicates the possibility of simultaneous fresh groundwater dilution activity along with a seawater ingression/intrusion process. Low rainfall and excessive withdrawal of groundwater has caused the increase of saline water intrusion. 相似文献
97.
It is shown that an analog of Birkhoff’s theorem of general relativity exists in the Einstein–Cartan–Kalb–Ramond (ECKR) theory
of gravity when Kalb–Ramond (KR) field strength, which occurs in the theory is independent of time. 相似文献
98.
Somenath Chakrabarty 《Journal of Astrophysics and Astronomy》1995,16(3-4):399-405
The effect of intense magnetic field on the cosmic quark-hadron phase transition and also on the baryon number inhomogeneity
has been investigated using phenomenological MIT bag model for the quark sector. For the sake of simplicity an ideal gas equation
of state has been considered for the hadronic phase. 相似文献
99.
N. C. Mondal A. B. Bhattacharya S. K. Sarkar R. Bhattacharya A. K. Sen 《Theoretical and Applied Climatology》1996,54(3-4):229-234
Summary A study of rain rate and rain induced attenuation characteristics over two tropical stations in India has been made. The observed rain rate distributions differ significantly when compared with the CCIR report. The refractive indices have been calculated for certain frequencies at a tropical rain temperature of 20°C showing the variational pattern at different millimeter wavelengths. The present analysis also reveals that in the range 0.05 cm–0.3 cm drop diameter the variations of scattering amplitudes are systematic while in the range 0.4 cm–0.6 cm they are irregular.With 6 Figures 相似文献
100.
Calculation of excess disease burden for As exposed populations is becoming increasingly important to enable quantitative estimation of the impacts of various As mitigation options. There are several methods by which such calculations may be carried out. In this study, two methods, recently applied to estimating groundwater As-related health risks in southern Asia, to estimate disease burden arising from lung, bladder and liver cancer from As exposure for an As-effected area of West Bengal have been compared. Both utilized calculated distributions of exposure of the studied population to As from groundwater. Method (I) then entailed calculating disease burden by combining published background rates for death and disability adjusted life years (DALYs) and standard mortality ratios (SMRs) for excess health impacts related to As exposure, whilst for Method (II), disease burden from As exposure was estimated using the basic DALY formula, combined with incidence rates based on the NRC multistage Weibull model. Dose–response data for both methods were based on studies in Taiwan. 相似文献