Impact of Topography on Accuracy of Land Cover Spectral Change Vector Analysis Using AWiFS in Western Himalaya

The present paper discusses the impact of topography on accuracy for land cover classification and “from-to class change using improved spectral change vector analysis suggested by Chen et al. (2003). Two AWiFS sensor images of different dates are used. Double Window Flexible Pace Search (DFPS) is used to estimate threshold of change magnitude for change/no change classes. The topographic corrections show accuracy of 90% (Kappa coefficient 0.7811) for change/no change area as compared to 82% (Kappa coefficient 0.6512) in uncorrected satellite data. Direction cosines of change vector for determining change direction in n-dimensional spectral space is used for image classification with a minimum distance categorizing technique. The results of change detection are compared (i) Improved CVA with conventional two bands CVA and (ii) Improved CVA before and after topographic corrections. The improved CVA with topographic correction consideration using slope match show maximum accuracy of 90% (Kappa coefficient 0.83) as compared to conventional CVA which show maximum accuracy of 82% (Kappa coefficient 0.6624). The overall accuracy of ”from- to class using improved CVA increases from 86% (Kappa coefficient 0.7817) to 90% (Kappa coefficient 0.83) after topographic corrections. The improved CVA with proper topographic corrections is found to be effective for change detection analysis in the rugged Western Himalayan terrain.     

Physiography of the tons basin,Western Himalaya

Landsat RBV imagery on 1:500,000 was interpreted to prepare small scale physiography map of the part of the Tons basin. Aerial photographs on 1:60,000 to 1:80,000 scale were interpreted to prepare medium scale physiography map of the basin. The basin has been sub-divided into three physiographic regions viz. High to very high mountains constituting of glaciated and temperate high mountains; Low to moderately high mountains and very low maountains. The physiographic regions have been further sub-divided based on landforms, slope and dissection index. The major physiographic units are summits, repose slopes, serrated ridges with horn/arates; mountain and valley glaciers, morains, solufluction terraces, intrenched incised river valleys, engrown valleys, alluvial terraces, rocky slopes/cliffs and debris.     

Vegetation analysis and study of its dynamics in Chandaka Wildlife Sanctuary (Orissa) using aerospace remote sensing

Changes brought in habitat conditions due to increasing human influences on natural areas have posed serious threat to wildlife. Remote Sensing has probably omerged as one of the most viable techniques to assess and monitor habitat conditions. Comparative analysis of maps of two-time period can provide authentic data with respect to changes brought in the habitat conditions. Chandaka Wildlife Sanctuary, covering an area of 213.71 sq. km in Orissa is one of the natural reserves of elephants which has undergone serious changes brought in through anthropogenic activities of urban areas of Cuttack and Bhubaneshwar lying within the proximity of the sanctuary. The natural reserve, an ideal habitat for elephants, was connected to neighbouring extensive forest belts. These connections have been either degraded or deforested over the years. The present study analyses the types of habitat available in the sanctuary using remote sensing data (aerial and satellite). Vegetation-type maps of 1975 have been prepared from B/W aerial photographs of 1:25,000 scale. For assessing the current vegetation types, maps have been prepared from Indian Remote Sensing Satellite (LISS II) false colour composite on 1:50,000 scale. Comparative evaluation of the maps indicates changes in the vegetation pattern, increase in mining and agriculture areas within the sanctuary. Stratified field sampling of vegetation types provide structural characteristics of the vegetation. Bamboo has been found to extend in the valleys and side slopes of the sanctuary area during past 15 years. An analysis on response of vegetation in all major vegetation types mapped have been made in the context of the invasion of Eupatorium odoratum. Finally, bamboo biomass has been assessed through stratified random sampling as it constitutes a major elephant food source.     

Assessing the Priorities for Sustainable Forest Management in the Sikkim Himalaya,India: A Remote Sensing Based Approach

Sikkim is a small, mountainous, Indian state (7,096 km²) located in the eastern Himalayan region. Though a global biodiversity hotspot, it has been relatively less studied. A detailed forest type, density and change dynamics study was undertaken, using SATELLITE remote sensing data and intensive field verification. The landscape was found to be dominated by alpine and nival ecosystems, with a large portion above the tree line, considerable snow cover, and a sizeable area under forest cover (72%, 5,094 km²). A total of 18 landscape components including 14 vegetation classes were delineated, with the major ones being oak forest, alpine meadow, alpine scrub, conifer forest and alder-cardamom agro-forestry. Of the 3,154 km² of forests below the tree line, 40% were found to be dense (>40% tree canopy cover). A sizeable portion of the non dense forests below the tree line was contributed by the degradation of oak forests, which was confirmed by change detection analysis. However on a positive front over the past decade, ban on grazing and felling of trees in forests has been implemented. In order to expand the extent of dense forests, further efforts are needed for the restoration of oak forests such as fire protection, providing alternatives to firewood use, promotion of alder-cardamom agro-forestry in the private lands and protection of the small-sized, fragmented forest patches in the subtropical belt.     

Mapping the Extent of Agroforestry Area in Different Altitudes of Tehri District,North Western Himalaya,India Through GIS and Remote Sensing Data

Assessment of area under agroforestry in Tehri district of North Western Himalaya, Uttarakhand, India has been done using GIS and remote sensing technology. The study district characterized by hilly terrain with varying elevations from 288 m to more than 2800 m and generally gentle slopes, valleys, flat land covers and agricultural terraces. High-resolution satellite imageries (spatial resolution 5.8 m) were used in this study for land uses and land covers classification. According to unsupervised classification, highest area was found under forest class (65.22%) followed by cropland (20.41%). Considerable area was also found under snow cover (9.45%) in the district. Area under agroforestry was estimated to be 5572.26 ha (1.53%) by this method, whereas it was estimated to be 7029.06 ha (1.93%) by supervised classification. Estimated cropland area comes out to be about 20.0%. An accuracy of 86.5% was found in this classification for agroforestry class. Highest area under agroforestry of 3707.36 ha was obtained in 1200–2000 m elevations followed by 2231.26 ha in 288–1200 m elevations. Negligible area was found on high elevation zones of more than 2800 m. The major agroforestry systems of dominated by Grewia oppositifolia (Bhimal), Celtis australis (Kharik) and Quercus leucotrichophora (Banj) were identified and mapped and remaining systems were grouped as others class. Estimated area under G. oppositifolia, C. australis and Q. leucotrichophora based systems come out to be 2330.82, 1456.80 and 1129.10 ha, respectively. These systems are multiple usufructs are food, fuelwood, fodder, fiber and small timber. It has been observed from the accuracy assessment that the estimates of area under agroforestry obtained under this study are reliable.     

Glacier surface characteristics derivation and monitoring using Hyperspectral datasets: a case study of Gepang Gath glacier,Western Himalaya

Mountain Glaciers are natural resources of fresh water and these affect the stream flow of the rivers, regional climate and further global climate. Observed trends and projected future evolutions of climate and Cryospheric variables clearly suggest a need to monitor these changes. Accordingly, the article presents the glacier features mapping using Hyperspectral remote sensing imagery. A freely available Hyperion satellite imagery acquired over Gepang Gath glacier in Himachal Pradesh, India is used for the study. Each class is identified based on their surface characteristics of spectral reflectance properties. Identification is simplified by demarcating the study glacier into accumulation and ablation areas through snowline. Accumulation area is characterized with high reflectance clean snow/ice and reduced moderate reflectance Snow/firn. The identification of classes in Hyperion imagery is validated using the spectral library from USGS and ASTER, and field spectra obtained from literature.     

Terrestrial photogrammetric mapping of the Neh-Nar glacier in Himalaya, India

Terrestrial photogrammetry holds distinct advantages over the conventional theodolite survey or aerial photogrammetry for glacier surveys, on account of inaccessibility of upper reaches of the glaciers and non-suitability of large-scale aerial photography for very high relief areas. The Neh-Nar glacier was mapped with a contour interval of 10 m utilising terrestrial photogrammetric techniques because no large-scale base map of the glacier was available for detailed glaciological studies. This glacier was selected under the International Hydrological Programme. Apart from topographic details various features of glaciological significance like transient snowline, accumulation and ablation zones, bergschrund, icefalls etc., were also mapped.     

Detection of Changes in Glacier Mass Balance Using Satellite and Meteorological Data in Tirungkhad Basin Located in Western Himalaya

Himalayan glaciers and their mass balance are poorly sampled through direct mass balance measurements. Thus, based on Landsat datasets of ETM⁺ (2000), ETM⁺ (2006) and TM (2011), mass balance studies of 32 glaciers was carried out using accumulation area ratio (AAR) method in the Tirungkhad river basin, a tributary of Satluj River, located in western Himalayan region. The overall specific mass balance was negative varying from ?27 cm (2000) to ?41 cm (2011). Out of 32 glaciers, 27 glaciers (81.2 %) showed negative mean mass balance and 5 glaciers (18.7 %) showed positive mean mass balance. Mean of specific mass balance for the year 2000, 2006 and 2011 was found to be ?48 cm, ?55 cm and ?0.61 cm respectively, in case of glaciers with negative mass balance while in case of glaciers with positive mass balance, it was 0.67 cm (2000), 0.56 cm (2006) and 0.47 cm (2011). The investigations suggested a loss of ?0.034 km³ of glacial ice for 2000, 0.036 km³ for 2006 and 0.038 km³ for 2011 respectively. The negative mass balance of the glaciers since 2000 correlates well with the increasing trend of annual mean temperature and decreasing trend of precipitation (snow water equivalent (SWE) and rainfall). Based on Mann Kendall test the temperature and SWE trends were significant at 95 % confidence level, however, the rainfall trend was insignificant.     

基于多源遥感数据的北极新冰提取及范围时序变化分析

海冰密集度（sea ice concentration, SIC）是北极海冰及气候变化研究的重要参数。国产风云3D卫星搭载的微波成像仪（microwave radiation imager,MWRI）获得的被动微波数据可用于SIC的估算,但其精度评价没有得到足够的重视。围绕MWRI数据应用于北极SIC估算精度开展研究,研究对比了专用微波成像仪（special sensor microwave imager sounder,SSMIS）、MWRI和先进微波扫描辐射计2（advanced microwave scanning radiometer 2,AMSR2）3种被动微波数据和Bootstrap（BST）、NASA Team（NT）、基于全约束最小二乘（fully constrained least squares,FCLS）、Enhanced NASA Team（NT2）、ASI（Arctic radiation and turbulence interaction study (ARTIST) sea ice）和FCLS-P 6种方法估算的SIC,并与船测数据进行了比较。结果表明,MWRI数据在12.5 km和25 km空间分辨率下均获得较优的SIC估算精度（20.4%~24.4%）。此外,MWRI数据在夏季和冬季都表现较好（夏季为17.9%~23.0%,冬季为11.2%~17.8%）。因此,MWRI具有较稳定的性能,在北极海冰参数的监测研究中极具潜力。     

Assessing changes in the above ground biomass and carbon stocks of Lidder valley,Kashmir Himalaya,India

The changes in the land use and land cover (LULC), above ground biomass (AGB) and the associated above ground carbon (AGC) stocks were assessed in Lidder Valley, Kashmir Himalaya using satellite data (1980–2013), allometric equations and phytosociological data. Change detection analysis of LULC, comprising of eight vegetation and five non-vegetation types, indicated that 6% (74.5 km²) of the dense evergreen forest has degraded. Degraded forest and settlement increased by 20 and 52.8 km², respectively. Normalized difference vegetation index was assessed and correlated with the field-based biomass estimates to arrive at best-fit models for remotely sensed AGB estimates for 2005 and 2013. Total loss of 1.018 Megatons of AGB and 0.5 Megatons of AGC was estimated from the area during 33-year period which would have an adverse effect on the carbon sequestration potential of the area which is already facing the brunt of climate change.     

Estimation of Snow Cover Area,Snow Physical Properties and Glacier Classification in Parts of Western Himalayas Using C-Band SAR Data

Snow physical properties, snow cover and glacier facies are important parameters which are used to quantify snowpack characteristics, glacier mass balance and seasonal snow and glacier melt. This study has been done using C-band synthetic aperture radar (SAR) data of Indian radar imaging satellite, radar imaging satellite-1 (RISAT)-1, to estimate the seasonal snow cover and retrieve snow physical properties (snow wetness and snow density), and glacier radar zones or facies classification in parts of North West Himalaya (NWH), India. Additional SAR data used are of Radarsat-2 (RS-2) satellite, which was used for glacier facies classification of Smudra Tapu glacier in Himachal Pradesh. RISAT-1 based snow cover area (SCA) mapping, snow wetness and snow density retrieval and glacier facies classification have been done for the first time in NWH region. SAR-based inversion models were used for finding out wet and dry snow dielectric constant, dry and wet SCA, snow wetness and snow density. RISAT-1 medium resolution scan-SAR mode (MRS) in HV polarization was used for first time in NWH for deriving time series of SCA maps in Beas and Bhagirathi river basins for years 2013–2014. The SAR-based inversion models were implemented separately for RISAT-1 quad pol. FRS2, for wet snow and dry snow permittivity retrieval. Masks for layover and shadow were considered in estimating final snow parameters. The overall accuracy in terms of R² value comes out to be 0.74 for snow wetness and 0.72 for snow density based on the limited ground truth data for subset area of Manali sub-basin of Beas River up to Manali for winter of 2014. Accuracy for SCA was estimated to be 95 % when compared with optical remote sensing based SCA maps with error of ±10 %. The time series data of RISAT-1 MRS and hybrid data in RH/RV mode based decompositions were also used for glacier radar zones classification for Gangotri and Samudra Tapu glaciers. The various glaciers radar zones or facies such as debris covered glacier ice, clean or bare glacier ice radar zone, percolation/refreeze radar zone and wet snow, ice wall etc., were identified. The accuracy of classified maps was estimated using ground truth data collected during 2013 and 2014 glacier field work to Samudra Tapu and Gangotri glaciers and overall accuracy was found to be in range of 82–90 %. This information of various glacier radar zones can be utilized in marking firn line of glaciers, which can be helpful for glacier mass balance studies.     

Evaluation of water discharge and sediment budget in the lesser Himalaya

This paper deals with the quantitative measurement of water discharge and sediment budget, comparison of the quantitative data of the middle part of the Bino Valley at the boundary of Pauri Garhwal and Almora district of U.P. The Ghatgad Catchment is cultivated (70%), the Gungad Catchment is moderately forested (55%) and the Kolani Catchment is forested (95%). Based on the morphometric and drainage analysis, the water discharge, suspended load yield and rainfall (1995-96) has been computed. The maximum annual average discharge has been observed in moderately forested (Gungad, 70.3 LS^-1) and cultivated (Ghatgad, 67.6 LS^-1) catchments and minimum discharge (24.5 LS^-1) in the forested (Kolani) catchment. The highest monthly suspended load, amounting to 49.28 percent of the total annual load and a denudation rate 8.51 T/km²/month being observed in September for Ghatgad catchment., where as 47.64 percement of the total sediment and 4.06 T/km²/month being observed in August for Gungad catchment. In Kolani the highest monthly concentration of suspended load being (63.98%), of the total annual load and denudation rate 2.75 T/km²/month being observed in the month of June.     

Report on Cartographic and GIS Activity in the U.S. Fish and Wildlife Service

The U.S. Fish and Wildlife Service (FWS) is a federal agency whose mission is, working with others, to conserve fish and wildlife and their habitats for the continuing benefit of the American people. Under the management of fish and wildlife professionals, the National Wildlife Refuge System has become the world's premier network of wildlife habitats. The FWS is making use of modern cartographic methods and implementing Geographic Information Systems to more effectively manage the lands and resources entrusted to them.     

Geoinformatics based approach for estimating the sediment yield of the mountainous watersheds in Kashmir Himalaya,India

Sedimentation of water bodies is governed by the erosional processes occurring at the watershed level. In this research, a method is proposed for assessing the sediment yield of the mountainous watersheds surrounding the Wular lake in Kashmir Himalaya, using geoinformatics and geostatistics. This method is empirical and semi-quantitative in approach and takes into account the weightage-based influence of the parameters governing the watershed sediment yield. The results of this study reveal that out of the six surrounding watersheds of the Wular Lake, Madhumati watershed with the highest sediment yield index, SYI (39.78) drains maximum sediments into the Lake followed by Arin (39.27), Ferozpur (34.30), Wular II (32.53), Wular I (24.65) and Gundar (23.43) in the event of a same intensity storm. The proposed method is reasonably a better approach in the data-scarce Himalayan region and shall be a useful tool for watershed management in other regions with similar geographic setting.     

中国主要牧区雪灾遥感监测评估模型研究

该文以中国雪灾高发区的西藏那曲地区为例，主要介绍了在试验区雪灾背景数据库支持下，利用ＮＯＡＡ／ＡＶＨＲＲ卫星遥感资料对雪灾进行判别，预测及对灾情损失进行综合评估的一些技术和方法，其内容包括：（１）用于雪灾危险等级分析与判定的判别模型；（２）用于灾情发展趋势模拟与预测的预测模型；（３）用于灾情损失综合评估与估算的评介模型。并运用这些模型对１９９５年２－３月发生在西藏那曲的雪灾进行实时分析，其结果和实     

普通本科院校学生培养模式探索与实践

以吉林建筑大学测绘与勘查工程学院应用型转型和工程教育认证平台为基础,测绘工程专业学生为对象,以提高学生实践能力为核心,从教学计划、教学内容、实践能力提高、评价体系与反馈机制、教师培训等5个方面着手,研究了普通本科院校测绘工程专业学生培养模式的改革与完善,并应用于实际教学活动中,希望能为高校实践型人才培养提供借鉴。     

Study of alluvial and Talus Fans in the Garhwal Himalaya by remote sensing technique

Investigations were carried out in the Garhwal, with ranges of Lesser and Outer Himalaya. Alluvial and Talus Fans in this area are quite widespread and are generally coalescing in nature, covering linear zones almost parallel to the lesser and outer Himalyan Ranges. These fans and their deposits have been mapped and identified on the basis of the study of Landsat imagery and aerial photographs. They appear to be spreading outwordly from the escarpments often with divergent pattern of drainage. In all seven such zones of coalescing alluvial and talus fans have been identified. Zone 1 appear to be alluvial plain in front of the outer Himalayan Siwalik ranges. Zones 2, 3 and 4 may be infillings between the ranges. Whereas, zones 5, 6 and 7 may be pediplains within the Lesser Himalayan ranges. Based on the degree of their dissection, the fans in this area seems to be chronologically younger successively towards the outer parts of Himalaya.     

喜马拉雅主逆冲断层闭锁程度与滑动亏损特征研究

基于融合的GPS速度场结果,使用DEFNODE负位错反演程序估算了喜马拉雅主逆冲断层（the main Himalayan thrust,MHT）的闭锁程度和滑动亏损空间分布,并结合剖面结果分析了断层远、近场的运动特征。结果表明,MHT的闭锁深度基本达到18~24 km,断层面闭锁宽度达到102~136 km,两次历史大地震破裂区域之间的未破裂段落和未发生大地震的段落闭锁深度更深,闭锁断层面更宽,2015年尼泊尔Mw7.8大地震就发生在两次大地震破裂区域之间的段落;MHT总滑动亏损速率和垂直断层挤压滑动亏损速率自东向西逐渐减小,平行断层右旋滑动亏损速率则基本上自东向西逐渐增加;MHT 3条剖面拟合结果也反映出其存在很强的闭锁。根据估算的此次Mw7.8地震的复发周期230年和最近500多年发生的大地震分布,认为MHT整条段落尤其是尼泊尔西部与印度接壤处和可能还没有破裂的不丹地区依然有发生8级大地震的危险。