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71.
K. Satish Kumar K. N. S. S. S. Srinivas V. Pradeep Kumar P. Prabhakara Prasad T. Seshunarayana 《Journal of the Geological Society of India》2018,91(2):174-180
High ground magnetic anomalies are observed at western basin of the Sandur schist belt (SSB) near Muraripura village, Karnataka. Sources for these anomalies are inferred due to presence of exposed banded iron formations hosted by metabasalts, arenaous and argillaceous rocks associated with the Donimali Formation of the schist belt. Two varieties of BIF bands are observed in the study area viz. Band 1 and Band 2. The bands 1 and 2 are displaced by lateral strike-slip fault. Band 1 is dominantly composed of banded iron formation, rich in iron ore minerals and silica chert. Band 2 is largely composed of ferruginous quartzite and quartz arenites. Qualitative analysis of the magnetic data indicates that the study area can be divided into three lithologically important BIF/BQ formations. Spectral and quantitative analysis of the magnetic data indicates, the average depth of band 1 is 70 m and band 2 is 130 m. The magnetic data results are well correlated with chemical analysis of borehole and surface rock samples data. 相似文献
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Murali Krishna Gumma Prasad S Thenkabail Kumara Charyulu Deevi Irshad A Mohammed Pardhasaradhi Teluguntla Adam Oliphant 《地理信息系统科学与遥感》2018,55(6):926-949
Cropland fallows are the next best-bet for intensification and extensification, leading to increased food production and adding to the nutritional basket. The agronomical suitability of these lands can decide the extent of usage of these lands. Myanmar’s agricultural land (over 13.8 Mha) has the potential to expand by another 50% into additional fallow areas. These areas may be used to grow short-duration pulses, which are economically important and nutritionally rich, and constitute the diets of millions of people as well as provide an important source of livestock feed throughout Asia. Intensifying rice fallows will not only improve the productivity of the land but also increase the income of the smallholder farmers. The enhanced cultivation of pulses will help improve nutritional security in Myanmar and also help conserve natural resources and reduce environmental degradation. The objectives of this study was to use remote sensing methods to identify croplands in Myanmar and cropland fallow areas in two important agro-ecological regions, delta and coastal region and the dry zone. The study used moderate-resolution imaging spectroradiometer (MODIS) 250-m, 16-day normalized difference vegetation index (NDVI) maximum value composite (MVC), and land surface water index (LSWI) for one 1 year (1 June 2012–31 May 2013) along with seasonal field-plot level information and spectral matching techniques to derive croplands versus cropland fallows for each of the three seasons: the monsoon period between June and October; winter period between November and February; and summer period between March and May. The study showed that Myanmar had total net cropland area (TNCA) of 13.8 Mha. Cropland fallows during the monsoon season account for a meagre 2.4% of TNCA. However, in the winter season, 56.5% of TNCA (or 7.8 Mha) were classified as cropland fallows and during the summer season, 82.7% of TNCA (11.4 Mha) were cropland fallows. The producer’s accuracy of the cropland fallow class varied between 92 and 98% (errors of omission of 2 to 8%) and user’s accuracy varied between 82 and 92% (errors of commission of 8 to 18%) for winter and summer, respectively. Overall, the study estimated 19.2 Mha cropland fallows from the two major seasons (winter and summer). Out of this, 10.08 Mha has sufficient moisture (either from rainfall or stored soil water content) to grow short-season pulse crops. This potential with an estimated income of US$ 300 per hectare, if exploited sustainably, is estimated to bring an additional net income of about US$ 1.5 billion to Myanmar per year if at least half (5.04 Mha) of the total cropland fallows (10.08 Mha) is covered with short season pulses. 相似文献
73.
Natural Hazards - In this study, new hybrid artificial neural network (ANN) models were used for predicting the groundwater resource index. The salp swarm algorithm (SSA), particle swarm... 相似文献
74.
Ravi S. Prasad 《Climate Policy》2019,19(3):354-366
With poverty alleviation and sustainable development as key imperatives for a developing economy like India, what drives the resource-constrained state governments to prioritize actions that address climate change impacts? We examine this question and argue that without access to additional earmarked financial resources, climate action would get overshadowed by developmental priorities and effective mainstreaming might not be possible. A systematic literature review was carried out to draw insights from the current state of implementation of adaptation projects, programmes and schemes at the subnational levels, along with barriers to mainstreaming climate change adaptation. The findings from a literature review were supplemented with lessons emerging from the implementation of India’s National Adaptation Fund on Climate Change (NAFCC). The results of this study underscore the scheme’s relevance.Key policy insights
Experience with NAFCC implementation reveals that states require sustained ‘handholding’ in terms of financial, technical and capacity support until climate change issues are fully understood and embedded in the policy landscape.
Domestic sources of finance are critically important in the absence of predictable and adequate adaptation finance from international sources.
The dedicated window for climate finance fosters a spirit of competitive federalism among states and encourages enhanced climate action.
Enhanced budgetary allocation to NAFCC to strengthen the state-level adaptation response and create capacity to mainstream climate change concerns in state planning frames, is urgently needed.
75.
By using the upper bound finite‐elements limit analysis, with an inclusion of single and two horizontal layers of reinforcements, the ultimate bearing capacity has been computed for a rigid strip footing placed over (i) fully granular, (ii) cohesive‐frictional, and (iii) fully cohesive soils. It is assumed that (i) the reinforcements are structurally strong so that no axial tension failure can occur, (ii) the reinforcement sheets have negligible resistance to bending, and (iii) the shear failure can take place between the reinforcement and soil mass. It is expected that the different approximations on which the analysis has been based would generally remain applicable for reinforcements in the form of geogrid sheets. A method has been proposed to incorporate the effect of the reinforcement in the analysis. The efficiency factors, ηc and ηγ, to be multiplied with Nc and Nγ , for finding the bearing capacity of reinforced foundations, have been established. The results have been obtained (i) for different values of ? in case of fully granular and cohesive‐frictional soils, and (ii) for different rates at which the cohesion increases with depth for a fully cohesive soil. The optimum positions of the reinforcements' layers have also been determined. The effect of the reinforcements' length on the results has also been analyzed. As compared to cohesive soils, the granular soils, especially with higher values of ?, cause a much greater increase in the bearing capacity. The results compare reasonably well with the available theoretical and experimental data from literature. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Avijit Gupta M.A. Ph.D. P.P. Wong M.A. Ph.D. 《Singapore journal of tropical geography》1994,14(2):252-264
Our knowledge regarding the physical geography of Southeast Asia is incomplete to a surprising extent. This paper reviews the past research, describes the ongoing work, and attempts to identify the future trends. Coverage of such a large area, even for the last 25 years, requires study of publications in several languages and coping with literature which is not easily available. Therefore certain topics. which are prominent in current research and likely to remain so in the future were chosen and reviewed in detail. Such topics include studies related to active plate margin features; the Pleistocene in Southeast Asia; erosion and sedimentation rates; rainforest; river systems; karst in Southeast Asia; coastal geomorphology; and the urban environment. Environmental studies are rapidly gaining importance chiefly because of (a) the destruction of the natural vegetation and the associated loss of biodiversity and (b) the growing problems due to accelerated erosion and sedimentation This trend is likely to continue with accelerated destruction of forests, development of coastal areas, and urbanization of the landscape The direction of research in physical geography of Southeast Asia has been determined by a combination of individual research interest, governmental priorities, and international expectations 相似文献
80.
P.P. Wong M.A. Ph.D. Avijit Gupta M.A. Ph.D. 《Singapore journal of tropical geography》1994,14(2):295-309
Up to June 1993, 207 articles on physical geography have been published in the Malayan Journal of Tropical Geography (MJTG) (1953–57), Journal of Tropical Geography (JTG) (1958–79) and the Singapore Journal of Tropical Geography (SJTG) (1980–93). These articles are examined initially in terms of their sub-fields (Biogeography, Climatology, Geomorphology, Hydrology, and Soils), area of focus (the tropics, Africa, America, East Asia, South Asia, Southeast Asia excluding Malaysia and Singapore, Malaysia, Singapore, and Southwest Pacific) and the area of origin of the authors. The more significant papers in the sub-fields are indicated. Various factors influencing the contributions to the Journal and some insights on the contributions of local staff (Singapore and Malaysia) are also given. The significance of the Journal as an avenue for local and foreign authors and for papers on physical geography in the tropics is briefly evaluated. 相似文献