Effects of urbanization on river morphology of the Talar River,Mazandarn Province,Iran

In the present study, we investigate the effects of urbanization growth on river morphology in the downstream part of Talar River, east of Mazandaran Province, Iran. Morphological and morphometric parameters in 10 equal sub-reaches were defined along a 11.5 km reach of the Talar River after land cover maps were produced for 1955, 1968, 1994, 2005 and 2013. Land cover types changed extremely during the study period. Residential lands were found to have increased in area by about 1631%, while forest land and riparian vegetation decreased in by approximately 99.9 and 96.2%, respectively. The results of morphometric and morphological factors showed that average channel width (W) for all 11.5 km of the study river decreased by 84% during the study period, while the flow length increased by about 2.14%.     

Integrated resource study for conservation and management of Ropar wetland ecosystem, Punjab

Integrated resource study in Ropar wetland ecosystem was undertaken to analyse physiography, drainage, landuse and vegetation status. Various thematic maps have been prepared using black and white aerial photographs on 1:20,000 scale and IRS 1A LISS-II (FCC) on 1:50,000 scale. The Ropar wetland ecosystem is comprised of six major landforms i.e. Siwalik hills, Valley, Piedmont plain, Alluvial plain, River terraces and River courses. The study area show high drainage density with sub dendritic and sub parallel drainage. The area has poor vegetative cover which results in extensive erosion and sedimentation of Ropar lake. The water spread and. qualitative turbidity level in the notified wetland area was also monitored. Anthropogenic pressure, industrial pollution, sedimentation, eutrophication, illegal fishing and flooding have been identified as major threats to the wetland. Keeping in view the threats to Ropar wetland, the conservation measures have been suggested.     

Landuse/land cover change in Mumbai-Navi Mumbai cities and its effects on the drainage basins and channels — A study using GIS

The Mumbai-Navi Mumbai cities (Bombay and New Bombay) are among the highest populated cities in the country. The population pressure has caused drastic landuse change in the last seventy years. Multi-date data from SOI topographical maps and Landsat TM digital data have been used to study the landuse change. The change has been quantified using A GIS It was observed that 55% reduction in forest/agricultural land, while a 300% increase in built-up land has taken place in the last seventy years. This has affected the natural drainage system of the cities, causing flooding during monsoons. The quantum of draînage basin area and stream length, in the ten basins which drain the area, under influence of built-up land was found by using a map overlay of the drainage network map and landuse map of 1994. The results shed light on the extent of drainage network disruption within these two neighbouring cities.     

Monitoring the impact of coal mining and thermal power industry on landuse pattern in and around Singrauli Coalfield using Remote Sensing data and GIS

Singrauli Coalfield spreading over an area of about 300 sq km along Uttar Pradesh and Madhya Pradesh border in the central part of India, is witnessing rapid industrialisation due to a large number of open pit coal mining projects and Super Thermal Power Station (STPS). Large scale mining activities along with operation of STPS have generated a great deal of environmental stress not only on the landuse pattern but also on various ecosystems in this region. An integrated remote sensing study was conducted to assess the impact of industrialisation on landuse pattern in the area under reference. The multispectral, multi-temporal data (1975, 1986 & 1991) of LANDSAT MSS and TM duly supplemented with ground truth were studied for generation of multidate landuse maps. Data base for landuse for the years 1975, 1986 and 1991 was created using PAMAP GIS for landuse analysis and change detection for optimal utilisation, planning and management of land resources. The study has revealed that the areas under built-up land, mining and fly ash pond have increased substantially from 1975 to 1991. Loss in forest cover and agricultural land has occurred due to rapid industrialisation in this region. It has been observed from the comparison of 1986 and 1991 data that the wasteland generated due to deforestation for initiating coal mining projects has gradually been reclaimed under operation “Green Gold” launched by Northern Coalfields Ltd. Further the wastelands have been effectively utilised for establishing the STPS, townships as well as other infrastructures in this area.     

Monitoring landuse and landcover changes using landsat images

It is well known that changes in landuse and landcover e.g., vegetation, forests, soils, water quality etc. have a great impact on the economic and social development of a region. In most of these cases, a knowledge of existing landuse and landcover and its rate of change is essential prior to any planning activity. Remote Sensing, particularly from a satellite platform is potentially an effective and economic means to collect the data and to monitor changes occurring in landuse categories. This paper deals with a study carried out in Dehradun - Roorkee region for preparation of the landuse and landcover maps and monitoring changes, if any, over a period of 5 years, from landsat images using Visual Interpretation Techniques..     

Temporal change detection in river courses and flood plains in an arid environment through satellite remote sensing

Temporal changes in ephemeral river courses and associated flood plains, which could not be detected by Landsat MSS due to its poor spatial resolution of 80m, have been identified and mapped within 10% accuracy by Landsat TM False colour composite because of its higher spectral and spatial resolution of 30 m. Over a period of 28 years (1958–86) the river courses widened upto 1.8 times through bank erosion due to the recurring flash floods. The flash floods have also caused morphological, soil fertility and landuse changes in the associated flood plains, which could also be monitored by the Landsat TM.     

Geomorphology and landuse of Pasighat-Jonai bazar area-A photo based study in a part of Dihang river basin,Arunachal pradesh and Assam

Photo-interpretation coupled with systematic field checks over an area of about 1500 sq. km has led to the identification of various landform units and their characteristic landuse pattern in part of the submontaneous tract of Arunachal Pradesh and Assam in the Dihang river basin. Four major geomorphic units have been mapped and their respective lithounits are studied in detail. Present landuse and the land’s capability inrespect of each of the major geomorphic units have been noted. Suggestions have been made for better utilisation of land.     

一种深度卷积神经网络土地利用场景照片的分类方法

国土调查多角度实景举证照片具有视角多、分辨率高、层次丰富和剖面清晰的特点,透视且细致地刻画了土地利用图斑赋存状况和场景,弥补了遥感影像单一天顶视角的不足。本文基于语义分割提出了一种深度卷积神经网络（DCNN）实景照片土地利用场景分类方法,多语义标记照片场景,语义组合智能判定照片土地利用类别。该方法成功地应用在第三次国土调查照片自动核查工作中,减轻了人工判读工作量,提高了土地利用场景自动识别的精度。     

The Palestine Exploration Fund Map (1871–1877) of the Holy Land as a Tool for Analysing Landscape Changes: the Coastal Dunes of Israel as a Case Study

Abstract

The Palestine Exploration Fund (PEF) maps (1871–1877) are highly praised for their accuracy and completeness; however, no systematic analysis of their accuracy has been done to date. To study the potential of these 1:63,360 maps for a quantitative analysis of land cover changes over a period of time, I have compared them to 20th century topographic maps. The map registration error of the PEF maps was 74.4 m using 123 control points of trigonometrical stations and a 1st order polynomial. The median RMSE of all control and test points (n = 1104) was 153.6 m. As a case study of land cover changes, the area of coastal dunes as shown on the PEF maps was compared with that shown on British Mandate 1:20,000 topo-cadastral maps from c. 1930. In five of the six areas analysed, the yearly dunes movement rate was above the estimated annual error due to data resolution (2.96 m/year). The rate of dune movement south of Acre was found to be between 3.9 and 6.3 m/year (depending on the method used for map registration) between 1874 and 1930. Care should be taken when analysing historical maps, as it cannot be assumed that their accuracy is consistent at different parts or for different features depicted on them.     

THE MAPPING OF FLOODPLAIN VEGETATION ON A LANDSCAPE BASIS

A “genetic” principle for the identification of morphological units on a floodplain landscape is applied to the mapping of vegetation and, more specifically, to a study of the spatial distribution of forest vegetation within the Ob' River floodplain. Aspects of the problem which are discussed include the identification and ranking of floodplain units and their components and appropriate scales for image interpretation and mapping. The principles and procedures outlined are applicable to the mapping of other floodplains. Translated by Edward Torrey, Alexandria, VA 22308 from: Geografiya i prirodnyye resursy, 1989, No. 2, pp. 78–84.     

黄土丘陵区数字地貌模型与遥感影象分类

黄土丘陵区地形破碎、沟壑纵横，为遥感影象的土地利用自动分类带来了很大困难。仅依靠传统的光谱统计分类方法，难以达到较高的分类精度。本文拟探讨在黄土丘陵区运用大比例尺地形图数据，建立区域数字地貌模型；并在模糊数学理论的指导下，运用数字地貌模型对影象的分层分类结果进行修正和细化。研究表明，此方法能够有效地提高土地利用分类精度和机助制图比例尺。     

Combined use of groundwater modeling and potential zone analysis for management of groundwater

A methodology for groundwater evaluation has been developed by the combined use of numerical model and spatial modeling using GIS. The developed methodology has been applied on the sub-basin of the Banganga River, India. Initially, the groundwater potential zones have been delineated by spatial modeling. Different thematic maps of the basin like geology, geomorphology, soil, drainage, slope factor and landuse/landcover have been used to identify the groundwater potential zones. Further, the groundwater flow model for the study area has been developed in the MODFLOW. The groundwater flow vector map has been developed and superimposed on the potential zone map to validate the results of spatial modeling. Finally, the different scenarios have been conceptualized by varying the discharge of the wells and purposing the location for new rainwater harvesting structures. Results reveal that increasing the discharge of the wells in the potential zones put less stress on the aquifer. The suggested locations of rainwater harvesting structures also help to reduce the overall decline of groundwater in the area. The hydrological and spatial modeling presented in this study is highly useful for the evaluation of groundwater resources and for deciding the location of rainwater harvesting structures in semi-arid regions.     

Delineation of ground water potential zones in a hard Rock Terrain of Bargarh District, Orissa using IRS data

In the present paper, various groundwater potential zones for the assessment of groundwater availability in a hard rock terrain have been delineated with the help of hydrogeological parameters using satellite IRS- 1B-LISS-II digital data. Area selected for this study is a part of Bargarh district, Orissa, India covering an area of about 680 square km. Satellite data has been used to prepare geological-cum-lineaments, geomorphological, landuse and drainage maps. The various thematic maps have been integrated with the help of Geographic Information System to demarcate the poor to excellent groundwater potential zones. Weightage has been given to various groundwater controlling factors to the total groundwater potential in each segment of study area. Subsequently, several sites were selected and pumping tests carded out in the area. The results show that among others, lineaments as well as drainage density are the most important contributory factors in the groundwater potential of various geomorphic units in the area of investigation.     

Mass Balance Estimation of Dokriani Glacier in Central Indian Himalaya Using Remote Sensing Data

Dokriani Glacier is regarded as one of the important glaciers of Bhagirathi River basin, which fed river Ganges. The length of the glacier is about 4.6 km, and snout elevation is about 4028 m m.s.l. The mass balance of this glacier was calculated using field-based measurements for few years during 1994 to 2000. However, due to remote and poor accessibility, the field-based measurements could not continue; thus, remote sensing-based methods become useful tool to estimate the long-term mass balance of the glacier. In this study, glacier mass balance has been determined using accumulation area ratio (AAR) method. Remote sensing data sets, e.g. Landsat TM, ETM?+?and OLI, have been used to estimate AAR for different years from 1994 to 2014. An attempt has also been made to develop a mathematical relationship between remote sensing-derived AAR and field-observed mass balance data of the glacier. Further, this relationship has been used to estimate mass balance of the glacier for different years using remote sensing-derived AAR. Estimated mass balance was validated from ground-observed mass balance for few years. The field-observed and remote sensing-derived mass balance data are compared and showed high correlation. It has been observed that AAR for the Dokriani Glacier varies from 0.64 to 0.71. Mass balance of the glacier was observed between ??15.54 cm and ??50.95 cm during the study period. The study highlights the application of remote sensing in mass balance study of the glaciers and impact of climate change in glaciers of Central Indian Himalaya.     

Tracking long-term floodplain wetland changes: A case study in the China side of the Amur River Basin

Floodplain wetlands in the China side of the Amur River Basin (CARB) undergone consistent decreases because of both natural and anthropogenic drivers. Monitoring floodplain wetlands dynamics and conversions over long-time periods is thus fundamental to sustainable management and protection. Due to complexity and heterogeneity of floodplain environments, however, it is difficult to map wetlands accurately over a large area as the CARB. To address this issue, we developed a novel and robust classification approach integrating image compositing algorithm, objected-based image analysis, and hierarchical random forest classification, named COHRF, to delineate floodplain wetlands and surrounding land covers. Based on the COHRF classification approach, 4622 Landsat images were applied to produce a 30-m resolution dataset characterizing dynamics and conversions of floodplain wetlands in the CARB during 1990–2018. Results show that (1) all floodplain land cover maps in 1990, 2000, 2010, and 2018 had high mapping accuracies (ranging from 90 %±0.001–97%±0.005), suggesting that COHRF is a robust classification approach; (2) CARB experienced an approximately 25 % net loss of floodplain wetlands with an area declined from 8867 km² to 6630 km² during 1990–2018; (3) the lost floodplain wetlands were mostly converted into croplands, while, there were 111 km² and 256 km² of wetlands rehabilitated from croplands during periods of 2000–2010 and 2010–2018, respectively. To our knowledge, this study is the first attempt that focus on delineating floodplain wetlands at a large-scale and produce the first 30-m spatial resolution dataset demonstrating long-term dynamics of floodplain wetlands in the CARB. The COHRF classification approach could be used to classify other ecosystems readily and robustly. The resultant dataset will contribute to sustainable use and conservation of wetlands in the Amur River Basin and provide essential information for related researches.     

Preparation of optimal land use maps for agricultural development using remote sensing techniques

Optimal land use map of Kanholi area, part of Nagpur district,Maharashtra have been prepared using Satellite imagery in 1:1000,000 and 1:250,000 and aerial photographs in 1:60,000 scale with adequate ground checks. The Satellite imagery proved valuable information about landscape characteristics, land use, hydrology and other environmental features. The aerial photographs were used to prepare comparatively large scale land resource association maps in scale 1:60,000 on geomorphology, landuse, soil hydrology. Soil irrigability, land irrigability and land capability maps are also attempted after interpreting soils information collected during field studies. The utility of this technique in preparation of optimal land use map with associated limitations due to scale have been discussed in the paper.     

Landsat data in preinvestment surveys—a case study of western Nepal area

In this paper an attempt has been made to estimate the growingstock showing high (51% and up), medium (25–50%) and low (below 25%) density areas and to prepare a broad landuse and forest cover type map by analysing black and white band 5 Satellite imagery (Landsat-1) on 1:1 m scale pertaining to Western Nepal area which comprises Karnali, Bheri, Babai and Rapti Catchments covering a geograghical area of about 50,000 sq km. The information regarding location, extent and area falling in forested and non-forested categories arrived at from Landsat maps provide basic information to planners at the time of formulation of inventory design before taking up preinvestment Surveys. In developing countries where vegetation stock maps are not readily available, forest resources map based on analysis of Landsat data can be prepared in less time and at a lower cost. Such maps may be immensely used by planners at regional or national level. The technique merits further investigation.     

Hydrological modelling of a small watershed using satellite data and gis technique

A distributed parameter model Soil and Water Assessment Tool (SWAT) has been tested on daily and monthly basis for estimating surface runoff and sediment yield from a small watershed “Chhokeranala” in eastern India using satellite data and Geographical Information System (GIS). Several maps like watershed and sub-watershed boundaries, drainage network, landuse/cover and soil texture have been generated. The SWAT model has been verified for the initial phase of monsoon season in the year 2002 using daily rainfall and air temperature. Performance of the model has been also evaluated to simulate the surface runoff and sediment yield on sub-watershed basis for two months (July-August 2002). The results show a good agreement between observed and simulated runoff and sediment yield during the study period. Capability of the model for generating rainfall has been evaluated for 10 years (1992 - 2001) period. The model simulated daily rainfall shows close agreement with the observed rainfall. The present results show that the SWAT model can be used for satisfactory simulation of daily and monthly rainfall, runoff and sediment yield.     

Shoreline and coral reef ecosystem changes in gulf of Mannar, Southeast coast of India

Changes in shoreline, coral reef and seafloor have been mapped using remote sensing satellite data of IRS LISS-III (1998), IRS LISS-II (1988), Survey of India Topographic sheet (1969), Naval Hydrographic Chart (NHO) 1975 and bathymetry data (1999) with ARC-INFO and ARC-VIEW GIS. The analysis of multi-date shoreline maps showed that 4.34 and 23.49 km2 of the mainland coast and 4.14 and 3.31 km² areas of island coast have been eroded and accreted, respectively, in the Gulf of Mannar. The analysis of multi-date coral reef maps showed that 25.52 km² of reef area and 2.16 km² of reef vegetation in Gulf of Mannar have been lost over a period of ten years. The analysis of multi-date bathymetry data indicates that the depth of seafloor has decreased along the coast and around the islands in the study area. The average reduction of depth in seafloor has been estimated as 0.51m over a period of twenty four years. The increased suspended sediment concentration due to coastal and island erosion, and raised reef due to emerging of coast by tectonic movement are responsible for coral reef degradation in the Gulf of Mannar. Validation by ground truth has confirmed these results.     

Use of WorldView-2 time series to establish a wetland monitoring program for potential offsite impacts of mine site rehabilitation

The Ramsar-listed wetlands of the Magela Creek floodplain, situated in the World Heritage Kakadu National Park, in northern Australia are recognised for their biodiversity and cultural values. The floodplain is also a downstream receiving environment for Ranger uranium mine, which is entering closure and rehabilitation phases. Vegetation on the floodplain is spatially and temporally variable which is related to the hydrology of the region, primarily the extent and level of inundation and available soil moisture. Time-series mapping of the floodplain vegetation will provide a contemporary baseline of annual vegetation dynamics to assist with determining whether change is natural or a result of the potential impacts of mine closure activities such as increased suspended sediment moving downstream. The research described here used geographic object-based image analysis (GEOBIA) to classify the upper Magela Creek floodplain vegetation from WorldView-2 imagery captured over four years (2010–2013) and ancillary data including a canopy height model. A step-wise rule set was used to implement a decision tree classification. The resulting maps showed the 12 major vegetation communities that exist on the Magela Creek floodplain and their distribution for May 2010, May 2011, June 2012 and June 2013 with overall accuracies of over 80% for each map. Most of the error appears to be associated with confusion between vegetation classes that are spectrally similar such as the classes dominated by grasses. Object-based change detection was then applied to the maps to analyse change between dates. Results indicate that change between dates was detected for large areas of the floodplain. Most of the change is associated with the amount of surface water present, indicating that although imagery was captured at the same time of year, the imagery represents different stages of the seasonal cycle of the floodplain.