Field Measurements of Plant Emissivity Spectra: An Experimental Study on Remote Sensing of Vegetation in the Thermal Infrared Region     

M.?R.?PandyaEmail author  D.?B.?Shah  H.?J.?Trivedi  M.?M.?Lunagaria  V.?Pandey  S.?Panigrahy  J.?S.?Parihar 《Journal of the Indian Society of Remote Sensing》2013,41(4):787-796

Spectral features of plant species in the visible to SWIR (0.4–2.5 μm) region have been studied extensively, but scanty attention has been given to plant thermal infrared (TIR: 4–14 μm) properties. This paper presents preliminary results of a study that was conducted first time in India to measure radiance and emissivity properties of eight plant species in TIR spectral region in the field conditions using a FTIR (Fourier Transform Infrared) field spectroradiometer working in 4–14 μm at an agriculture experimental farm. Several spectral features in the emissivity spectra of plant species were observed that are probably related to the leaf chemical constituents, such as cellulose and xylan (hemicellulose) and structural aspects of leaf surface like abundance of trichomes and texture. Observations and results from the field measurements were supported by the laboratory measurements like biochemical analysis. These preliminary field emissivity measurements of leaves in TIR show that there is useful spectral information that may be detectable by field-based instrument. More detailed field and laboratory measurements are underway to explore this research theme.  相似文献   

Drought hazard assessment using geoinformatics over parts of Chotanagpur plateau region, Jharkhand, India   总被引：4，自引：3，他引：1  

Swati Pandey  A. C. Pandey  M. S. Nathawat  Manoj Kumar  N. C. Mahanti 《Natural Hazards》2012,63(2):279-303

Recurrent drought events in the Palamu district of Jharkhand state and the magnitude of drought losses primarily toward agricultural production in this dominantly monocropped region indicate the continuing susceptibility of the society to drought. This paper presents a method for spatial, geoinformatics-based assessment of agricultural, meteorological, and hydrological drought hazard in Palamu district. It was hypothesized that the key climatic, biophysical and social factors that define agricultural drought hazard were soils, geomorphology, drainage density, land use, and relief, whereas for meteorological drought hazard, it is rainfall, coefficient of variation of rainfall and for hydrological drought hazard, it is lithology, depth to water table, aquifer yield, and surface water bodies. The framework for the derivation of an agricultural, meteorological, and hydrological drought hazard map was created through the development of a numerical weighting scheme to evaluate the drought potential of the classes within each factor. A cumulative map created through spatial join of all the three types of drought provided a drought hazard scenario in totality. The area with different severity of drought hazards under cumulative drought hazards scenario (viz. very low (8.9?%), low (24.2?%), moderate (29.2?%), high (20.13), and very high (17.3?%)) revealed high drought proneness of the area and the usefulness of geoinformatics in better spatial prognosis of drought hazards.  相似文献   

Geochronological (Rb-Sr and Sm-Nd) studies on intrusive gabbros and dolerite dykes from parts of Northern and Central Indian cratons: Implications for the age of onset of sedimentation in Bijawar and Chattisgarh basins and uranium mineralisation     

U. K. Pandey  D. V. L. N. Sastry  B. K. Pandey  Madhuparna Roy  T. P. S. Rawat  Rajeeva Ranjan  V. K. Shrivastava 《Journal of the Geological Society of India》2012,79(1):30-40

The Dargawan gabbros intrusive into the Moli Subgroup of Bijawar Group, yielded Rb-Sr whole rock isochron age of 1967 ± 140 Ma. Based on the oldest age from overlying Lower Vindhyan (1.6Ga) and the underlying youngest basement ages (2.2 Ga), the time range of Bijawar sedimentation may be assigned as 2.1–1.6 Ga (Paleoproterozoic). Sm-Nd Model ages (T_DM), obtained, for Dargawan gabbros, is c. 2876–3145 Ma. High initial ⁸⁷Sr/ ⁸⁶Sr ratio of 0.70451 (higher than the contemporary mantle) and negative ɛ_Ndi (at 1.9 Ga) value of −1.5 to − 4.5, indicate assimilation of Archaean lower crustal component by the enriched mantle source magma at the time of gabbroic intrusion. The dolerite, from Damdama area, which is intrusive into the basement and overlying sediments of Chandrapur Group in the central Indian craton, yielded Rb-Sr internal isochron age of 1641 ± 120 Ma. The high initial ⁸⁷Sr/⁸⁶Sr ratio of 0.7098 and ɛ_Ndi value of −3.5 to −3.7 (at 1.6 Ga) is due to contamination of the mantle source magma with the overlying sediments. These dolerites have younger Sm-Nd Model ages (T_DM) than Dargawan gabbros as c. 2462–2675 Ma, which is similar to the age of the Sambalpur granite, from which probably sediments to this part of Chattisgarh basin are derived. Hence mixing of sediments with the Damdama dyke during its emplacement, gives rise to high initial ⁸⁷Sr/⁸⁶Sr and low initial ¹⁴³Nd/¹⁴⁴ ratios for these dykes. The c. 1600 Ma age indicates minimum age of onset of the sedimentation in the Chandrapur Group of Chattisgarh basin. Both the above mafic intrusions might have taken place in an intracratonic rift related (anorogenic) tectonic setting. This study is the first reliable age report on the onset of sedimentation in the Chandrapur Group. The total minimum time span of Chandrapur and Raipur Group may be 1.6 Ga to 1.0 Ga (Mesoproterozoic). The unconformably underlying Shingora Group of rocks of Chhattisgarh Supergroup thus indicates Paleoproterozoic age (older than 1.6 Ga). Most part of the recently classified Chattisgarh Supergroup and Bijawar-Vindhyan sequence are of Mesoproterozoic-Paleoproterozoic age and not of Neoproterozoic-Mesoproterozoic age as considered earlier. Petrographic study of basic dykes from Damdama area (eastern margin of Chattisgarh Supergroup) indicated presence of primary uranium mineral brannerite associated with goethite. This is the evidence of mafic intrusive providing geotherm and helping in scavenging the uranium from the surrounding and later alterations causing remobilisation and reconcentration of pre-existing uranium in host rocks as well as in mafic dyke itself otherwise mafic rocks are poor source of uranium and can not have primary uranium minerals initially. It can be concluded that mafic dykes have role in uranium mineralisation although indirectly.  相似文献   

Anomalous phosphorus episodes during Callovian-Oxfordian times in the Kachchh Basin,western India: Implications for palaeoclimate,productivity, and weathering     

Muthuvairavasamy Ramkumar  Matthias Alberti  Franz T. Fürsich  Dhirendra Kumar Pandey 《Chemie der Erde / Geochemistry》2012,72(2):141-148

The Upper Callovian-Oxfordian strata of the Kachchh Basin, western India, record three positive excursions of phosphorus. They have been documented in three sections of the Chari Formation from different parts of the basin. Corroboration of field and petrographic data with trends of major and trace elemental data and elemental ratios of the strata revealed that these excursions were coeval with reduced chemical weathering in the source area and significant reduction of siliciclastic influx to the depositional sites. The study also revealed the intrabasinal source of P, and minor sea-level fluctuations and resultant episodic sediment recycling as the causative factors. Considering the geographic locations of the three sections, the phosphorus anomalies seem to be controlled by a regional and/or basin-scale process, if not linked with global signals. Temporal resolution of these anomalies suggests that the processes were episodic and related to short term climate/relative sea-level cycles, the durations of which could be unraveled with high-resolution biostratigraphic data.  相似文献   

Evaluating the Long-term Urban Expansion of Ranchi Urban Agglomeration,India Using Geospatial Technology     

Amit Kumar  Arvind Chandra Pandey  Najmul Hoda  A. T. Jeyaseelan 《Journal of the Indian Society of Remote Sensing》2011,39(2):213-224

The present study analyzes the built-up expansion of Ranchi urban agglomeration over a period of about 8 decades from 1927–2005. Satellite images and topographical maps were used to evaluate land use dynamics during these periods. Built-up growth of 473.7% during 1927–2005 was primarily at the expense of agricultural land along with reduction of natural water bodies reflects negative impacts of built-up expansion, which increased many folds in recent decades. The built-up growth is also analyzed with reference to population growth, land consumption rate and land transformation. The land loss due to increasing built-up growth of Ranchi were compared with other capital regions and cities along with population increase to provide insight into the possible scenario of built-up expansion in Ranchi urban area.  相似文献   

A Spatial Database of Cropping System and its Characteristics to Aid Climate Change Impact Assessment Studies     

Sushma Panigrahy  Shibendu Shankar Ray  K. R. Manjunath  P. S. Pandey  S. K. Sharma  Anil Sood  Manoj Yadav  P. C. Gupta  N. Kundu  Jai Singh Parihar 《Journal of the Indian Society of Remote Sensing》2011,39(3):355-364

Cropping system study is not only useful to understand the overall sustainability of agricultural system, but also it helps in generating many important parameters which are useful in climate change impact assessment. Considering its importance, Space Applications Centre, took up a project for mapping and characterizing major cropping systems of Indo-Gangetic Plains of India. The study area included the five states of Indo-Gangetic Plains (IGP) of India, i.e. Punjab, Haryana, Uttar Pradesh, Bihar and West Bengal. There were two aspects of the study. The first aspect included state and district level cropping system mapping using multi-date remote sensing (IRS-AWiFS and Radarsat ScanSAR) data. The second part was to characterize the cropping system using moderate spatial resolution multi-date remote sensing data (SPOT VGT NDVI) and ground survey. The remote sensing data was used to compute three cropping system performance indices (Multiple Cropping Index, Area Diversity Index and Cultivated Land Utilization Index). Ground survey was conducted using questionnaires filled up by 1,000 farmers selected from 103 villages based on the cropping systems map. Apart from ground survey, soil and water sampling and quality analysis were carried out to understand the effect of different cropping systems and their management practices. The results showed that, rice-wheat was the major cropping system of the IGP, followed by Rice-Fallow-Fallow and Maize-Wheat. Other major cropping systems of IGP included Sugarcane based, Pearl millet-Wheat, Rice-Fallow-Rice, Cotton-Wheat. The ground survey could identify 77 cropping systems, out of which 38 are rice-based systems. Out of these 77 cropping systems, there were 5 single crop systems, occupying 6.5% coverage (of all cropping system area), 56 double crop systems with 72.7% coverage, and 16 triple crop systems with 20.8% coverage. The cropping system performance analysis showed that the crop diversity was found to be highest in Haryana, while the cropping intensity was highest in Punjab state.  相似文献   

Devonian ichnofossils from the Farakah Muth section of the Pin Valley,Spiti Himalaya     

S. K. Parcha  Shivani Pandey 《Journal of the Geological Society of India》2011,78(3):263-270

The Muth Formation is one of the most characteristic marker horizon traced throughout the northwestern Himalaya. The present studies were carried out in the Farakah Muth (Pin Valley) section of Spiti Basin. The formation uniformly consists of quartzarenite with a high textural and compositional maturity. The development of carbonate beds in the upper part of the Muth Formation separates it conformably from the overlying Lipak Formation. A variety of traces were observed throughout the succession, includes: Metaichna, Planolites, Skolithos, vertical and horizontal burrows. The presence of ichnofossils in the Muth Formation of the Farakah section indicates subtidal settings having soft sandy substrate, whereas, the gradual maturity of the quartz grains from base to top indicates deposition under high energy condition.  相似文献