Mapping,monitoring and conservation of Harike wetland ecosystem,Punjab, India,through remote sensing

The Ramsar Convention of IUCN held in 1971 in Iran raised global awareness of the conservation and management of wetlands. Wetlands, the transitional zones that occupy an intermediate position between dryland and open water, regulate the flow of water and nutrients, thereby facilitating optimum functioning of the physical and biological cycles of nature. Harike wetland in the Indian State of Punjab has been declared a wetland of international importance. Thus it is felt necessary to reclaim and develop Harike wetland for its optimum potential use, but a reliable and accurate wetland database is not available. This study aimed at the generation of a database in terms of landuse/landcover, extent of waterspread and its seasonal variation, aquatic vegetation status and turbidity levels of lake water, using multidate satellite data. The threats of the Harike wetland have been identified and adequate measures for its conservation and management suggested.     

Migratory bird habitat monitoring through remote sensing

Abstract

Unsupervised classification of Landsat-TM data was employed to identify habitats important for migratory birds in Costa Rica. The overall habitat classification accuracy was 70 per cent (Kappa correction). Mature forest could be identified with high accuracy (93 per cent) but Landsat-TM classification accuracy for major successional stages was low. Habitat availability and conversion rates from 1976 to 1986 were derived from multidate Landsat imagery supplemented with interpretation of historical air photos to document the specific types of habitat change. The major trend in habitat conversion between 1976 and 1984 was forest clearing followed by establishment of permanent pasture. Some of the pasture land was converted to perennial tree crops by 1986. The implication of habitat modification on groups and species of migrant land birds are discussed.     

Eyed drainages observed in IRS imagery in Tamil Nadu,India and their geological significance

It has been established beyond doubt that the drainage architecture and the fluvial histories of river systems give excellent indications not only on the surficial lithology but also on the ongoing morphotectonic processes of the planet Earth. Among the various drainage patterns, the 'eyed drainage' pattern is considered to be one of the most significant anomalies and such 'mega eyed' drainages interpreted from IRS-1A imagery in some of the major river systems in Tamil Nadu, Indian Peninsula, are found to signify ongoing tectonic movements in an otherwise seismically inert shield area.     

Delineation of groundwater recharge sites using integrated remote sensing and GIS in Jammu district,India

With the increasing demands for water due to increasing population, urbanization and agricultural expansion, groundwater resources are gaining much attention, particularly in the Kandi region of Jammu district, which faces acute shortages of drinking water throughout the year. Groundwater development programmes need a large volume of data from various sources. This study used integrated remote sensing and geographic information system (GIS) techniques to provide an appropriate platform for convergent analysis of multidisciplinary data and decision making for artificial recharge to groundwater. Thematic maps were constructed using merged Linear Imaging Self Scanner (LISS)‐III and Panchromatic (PAN) remote sensing data and aquifer parameter thematic layers were prepared from conventional field data. The thematic layers of the aquifer parameters were integrated and a map showing the potential zones for artificial recharge to groundwater was generated. By superimposing the drainage network map over this artificial recharge zone map, and also considering the terrain conditions for artificial recharge, suitable sites for replenishing groundwater in the study area were identified.     

Analysis of urban growth pattern using remote sensing and GIS: a case study of Kolkata,India

Urban growth pattern has a direct influence on urban development processes both at the city and neighbourhood levels, but on the other hand growth pattern is also affected by land and housing policy, current built-up area, available developable area, change in household count, population, economy, and others. Remote sensing and GIS techniques can be used to analyse and model the urban growth pattern. This study was carried out to identify and analyse the urban growth pattern of Kolkata, India. Several statistical methods were applied to recognize and analyse this pattern, which shows increasing dispersed development of the city with the declining population growth rate. Apart from the derived results, this study also shows the potentiality of remote sensing and GIS techniques for the analysis of urban growth patterns.     

Technical note Temporal remote sensing data and GIS application in landslide hazard zonation of part of Western ghat,India

Spatial and temporal multi-layered information is required to assess landslide hazard susceptibility. The manual method of data integration for targeting potential zones susceptible to landslide hazard is time consuming. The present study highlights the utility of temporal remotely-sensed data and knowledgebased Geographical Information Systems for collection, integration and analysis of spatially-oriented data, as well as in finding out the inherent relation between separate entities in parts of West ghat in India.     

Spatiotemporal modelling of methane flux from the rice fields of India using remote sensing and GIS

Rice fields have been accredited as an important source of anthropogenic methane, with estimates of annual emission ranging from 47 to 60 Tg per year, representing 8.5–10.9% of total emission from all sources. In this study, attempts have been made to derive the spatial and temporal pattern of methane emitted from the rice lands of India using an integrated methodology involving satellite remote sensing and geographic information system (GIS) techniques. Multidate SPOT VGT 10‐day Normalized Difference Vegetation Index (NDVI) composite data for a complete year were used to map the rice area, delineate single‐ and double‐cropped rice areas, crop calendar and growth stages. Rainfall, digital elevation and irrigation data were integrated to stratify the rice area into distinct categories related to methane emission. Preliminary analysis of the methane emission pattern was carried out using published values. The results show that around 91% of total methane emission results from wet‐season rice, contributing 4.66 Tg per year. The temporal pattern shows that August and September are the months of peak emission during the wet season, and March and April during the dry season.     

Groundwater assessment through an integrated approach using remote sensing,GIS and resistivity techniques: a case study from a hard rock terrain

Satellite data have been widely used in conjunction with Geographic Information System (GIS) techniques in groundwater resource management. Satellite data are useful for extracting various thematic maps required for groundwater assessment. In this study, Indian Remote Sensing (IRS) 1D LISS III and Landsat Thematic Mapper (TM)/Enhanced TM (ETM+) digital data, and digital elevation models (DEMs) from the Shuttle Radar Topography Mission (SRTM) along with other collateral data were analysed to create various thematic maps (geomorphology, landuse, lithology, lineament, soil, drainage density, river gradient and slope maps) required for groundwater modelling in a hard rock terrain of Bargarh district, Orissa, India. These thematic maps were assigned suitable weights and different rankings to the individual classes within each thematic map using Saaty's Analytical Hierarchy Process (AHP). A raster‐based empirical GIS model was developed for integrating the thematic maps to locate suitable groundwater prospective zones. The integrated thematic maps were in turn used to compute the Groundwater Potential Index (GWPI). GWPI values calculated in the study area were found to vary from 0.175 to 0.940. These GWPI values have been classified into various classes: very poor (<0.4), poor (0.4–0.5), moderate (0.5–0.6), good (0.6–0.7), very good (0.7–0.8) and excellent (>0.8). A final map showing very poor to excellent groundwater prospective zones was prepared. The results thus obtained were subsequently cross‐checked with resistivity survey and pumping test data. Very poor GWPI zones show low yields of 0.5 lps from weathered granite of resistivity 20–100 Ω m and thickness 0.5–6 m, while excellent GWPI zones show high yields of 5–7 lps from highly fractured granite of resistivity 100–300 Ω m and thickness 14–31 m. The results obtained from integration of the various thematic maps on the GIS platform produced a good match with the resistivity and pumping test data.     

Flood monitoring using microwave passive remote sensing (AMSR-E) in part of the Brahmaputra basin,India

In this work, Advanced Microwave Scanning Radiometer Earth Observing System (AMSR-E) signatures were analysed over some critical sites in Lakhimpur District in Brahmaputra basin, India, characterized by a high frequency of flooding events. The site is mostly covered by paddy fields. Results obtained were compared with water level measurements in three stations close to the main channel of the river. Information about surface temperature, which allowed us to estimate the emissivity, was also available. Investigations were carried out at the C, X, and K_a bands of the AMSR-E channel. A multi-frequency analysis indicated that the X band would represent a good compromise between resolution and sensitivity requirements, while at the C band the resolution was too coarse and at the K_a band the signatures were affected by raindrops. Samples collected during rain were eliminated using techniques based on the 89.0 GHz channel. However, even after this correction, the K_a band showed poor sensitivity due to higher attenuation by vegetation. The correlations between different pairs of variables, viz. polarization index (PI), water level (WL), and fractional water surface area (F _WS), were also investigated. At the X band, the water level was better correlated with the PI than with emissivity and other parameters defined in the literature. The correlation was good in cases of slow variation in WL. In cases of sudden variation in the river, the PI followed the variations with some time delay related to the propagation of water within the covered AMSR-E pixel.     

Shoreline evolution: GIS,remote sensing and cellular automata modelling

The evolution and more particularly the erosion of the coasts morphology is an important environmental subject. Both the study of the actual evolution of coasts via digital tools and their modelling for the sake of prediction are necessary. A study of the evolution of a section of the Algerian coastline with a geographical information system shows that erosion is the main factor for the shoreline evolution, in the absence of structures consolidating the beaches. Therefore, a qualitative numerical model of the erosion of a coastline is proposed. It relies on a coupling between a cellular automata sedimentation model and a bi-fluid hydrodynamical model based on the Lattice Boltzmann method. The current model is two-dimensional and simulates a cross-section of a virtual coastline. The virtual coastline exhibits a gradual erosion by the water, whose speed depends on the kind of perturbation applied on the water level.     

Towards an integrated geographic analysis system with remote sensing,GIS and consecutive modelling for snow cover monitoring

The paper discusses the design of an Alpine Snow Cover Analysis System (ASCAS) for monitoring snow cover variations in the Alps. It is shown how data such as snow cover data derived from satellite, climate, hydrologic, and topographic data, are programmed into the system. Possible techniques for analysing snow cover variations and results are presented. Furthermore, the integration of image processing and GIS techniques with applied models on a microcomputer-based system is described.     

Study of tectonics in relation to the seismic activity of the Dalvat area,Nasik District,Maharashtra, India using remote sensing and GIS techniques

Well‐documented geological data (from both field and satellite) in the Deccan Volcanic Provinces (DVP) in and around the Dalvat region, Nasik District, India has been analysed by Geographic Information System (GIS) techniques and reported in this paper so as to relate the geology and structures with recent seismicity. It has been the belief among earth scientists that the Deccan Traps in Maharashtra, India is tectonically stable as the region attained solidity long ago. However, recent activity in the study area altered this concept and it is now accepted that seismic activity is still continuing on a mild scale. As such, the need has arisen to take into consideration historical as well as recent geological data to study in detail the tectonic setup in the Deccan Traps.

Using the well‐known relationship between the shear zone, lineaments, and geomorphology, and incorporating these with tectonic events, an attempt has been made to explore the geology and structures in and around the Dalvat region. Field observations and signatures on remote sensing data show that there is evidence of fault traces in the form of shear zones and slickensides in the Deccan Traps near the Kosurde, Dhanoli, Chikhli, and Manchandar villages of the Nasik District. The study has further been incorporated with seismic density data. Magnitudes of 3.9 were recorded as the maximum micro‐epicentres, and they fell on the shear fractures detected in the area of study.

In order to identify seismically vulnerable areas, seismic hazard zonation (SHZ) mapping has been carried out. Different data layers, including structural, lithological, geomorphological, drainage, and soil have been visually interpreted, scanned, and rectified. A rose diagram of the lineaments shows trends in the NNE–SSW to NS falling on major seismic zones of the study area, showing weaker zones beneath the surface. Raster images were digitized for conversion to a vector coverage using ERDAS 8.6. and ArcGIS 8.3. The ordinal scale (qualitative) relative weighting rating technique was used to give a seismic hazard index (SHI) value to delineate various seismic hazard zones; namely very low, low, moderate, high, and very high.     

Land-use change analysis in Yulin prefecture,northwestern China using remote sensing and GIS

Rapid land-use change has taken place in many arid and semi-arid regions of China such as Yulin prefecture over the last decade due to rehabilitation measures. In this paper, land-use change dynamics were investigated by the combined use of satellite remote sensing and geographical information systems (GIS). Our objectives were to determine land-use transition rates among land-use types in Yulin prefecture over 14 years from 1986-2000 and to quantify the changes of various landscape metrics using FRAGSTATS, the spatial pattern analysis program for Categorical Maps. Using 30-m resolution Landsat Thematic Mapper (TM) data from the Institute of Remote Sensing Application (IRSA) in China, we classified images into six land-use types: cropland, forestland, grassland, water, urban and/or built-up land, and barren land. Significant changes in land-use occurred within the area over the study period. The results show the significant decrease in barren land was mainly due to conversion to grassland. Cropland increased by 3.39%, associated with conversions from grassland and barren land. The landscape has become more continuous, clumped and more homogeneous. The study demonstrates that the integration of satellite remote sensing and GIS was an effective approach for analysing the direction, rate and spatial pattern of land-use change.     

Interfacing remote sensing and GIS methods for sustainable rural development

Remote sensing and Geographical Information System (GIS) are two important tools in developmental planning. This study demonstrates their application in sustainable rural development planning especially for people at the grass root level, the farmers, in the Bahal-Singhani area of Bhiwani district, Haryana, in north-western India. A holistic approach was adopted considering the production and the conservation functions of the ecosystem. Remotely sensed data were utilized to assess the natural resources of the area. A thorough analysis of climatic, socio-economic and natural resources conditions was made. A set of rules was formulated and all the information was integrated to prepare realistic action plans. These action plans have found wide acceptance due to their practicability and soundness.     

Application of remote sensing and GIS for the demarcation of groundwater potential zones of a river basin in Kerala,southwest coast of India

An integrated hydrogeological investigation has been made to delineate the groundwater‐potential zones of the Muvattupuzha river basin, Kerala, along the southwest coast of India. The basin is characterized by charnockites and gneisses of Archean age covering more than 80% of the area and the remaining by Pleistocene laterites and Miocene formation. The basin receives high rainfall, measuring 3100 mm/year. However, acute water shortage occurs during the premonsoon season and hence, a number of dug wells are made to tap the groundwater. Seasonal rainfall during NE and SW monsoons is the major source of groundwater recharge. Further, hydrogeomorphology, geology, fracture systems and the slope of the terrain also play a significant role on the movement and behaviour of the groundwater of this basin. The integration of conventional and remote sensing data has been made through geographic information system (GIS) and it is found that about 50% of the area can be identified as very good or good potential zones, whereas the remaining area falls under moderate and poor categories. Most of the Muvattupuzha sub‐basin and the western part of the Kothamangalam and Kaliyar sub‐basins are classified as good groundwater‐potential zones, although the eastern upstream part of the basin has poor groundwater potential.     

Stratification of forest density and its validation by NDVI analysis in a part of western Himalaya,India using Remote sensing and GIS techniques

This study deals with the assessment of the status of forest density in the Kangra district of Himachal Pradesh, western Himalaya. A classified forest map of the area with an accuracy of 88.17% was produced using the hybrid classification method in Erdas Imagine. An IRS 1D LISS III satellite image was used for mapping and classification. Forest density was calculated in the ArcGIS environment by overlaying a mesh of uniform resolution cells (500 m×500 m) on a classified forest map. The forest density value of each cell was later used for the preparation of forest density contours. The forest density output was verified by Normalized Difference Vegetation Index (NDVI) analyses. The forest cover of the study area was found to be 34.3%. Baroh area had the highest (45.87%) forest density and Baijnath (18.65%) the lowest. Central and western regions of the district showed high‐value forest density contours (>50%). The derived NDVI values were compared against the forest density classes for assessing the accuracy of the results obtained. A positive correlation (r = 0.99) between NDVI values and forest density confirms the accuracy of the results.     

Geomorphic evolution of the Piedmont Zone of the Ganga Plain,India: a study based on remote sensing,GIS and field investigation

The geomorphic evolution of the Piedmont Zone of the Ganga Plain is not well understood, since the identification of various morpho-tectonic features in the field is very difficult because of the thick forest cover, extensive anthropogenic modifications in the landscape and easily reworkable gravels. Interpretation of satellite imagery, Digital Terrain Models (DTMs) and field data has helped in identification and mapping of various morpho-tectonic features in a hitherto unstudied part of the Piedmont Zone and the adjoining areas in north-western Ganga Plain, India. The Piedmont Zone has formed as a result of laterally coalescing alluvial fans of variable dimensions and talus deposits, and is traversed by active faults and thrusts. The variable subsidence rates along the basin margin (i.e. the Himalayan Frontal Thrust) and climatic events have controlled the accommodation space and basinward progradation of alluvial fans. The landscape of the Piedmont Zone is presently being continuously modified by the ongoing tectonic movements and seasonal climatic variations.     

Geochronological studies of strandlines of Saurashtra,India, detected by remote sensing techniques

Abstract

Using remote sensing techniques four strandlines parallel to the present coastline were detected in the 16-18 km wide coastal belt of the Saurashtra peninsula in western India. Geochronological studies of themiliolites, the principal deposit of this area, using the ²³⁰Th/²³⁴ method, yielded ages ranging from 52 to 235 thousand years. With strong evidence in favour of tectonic instability in the region, the average uplift rates of the standlines are calculated to range from 0-12 to 0p 58 mm/year.