Showing posts from June, 2020

Interpolation Process of Spatial Data in GIS Environment using QGIS

Introduction Continuous spatial data is very important in many applications for spatial analysis. So for such analysis, acquiring continuous spatial data is very difficult, costly and usually takes very long time for study area. In case, if one needs to collect/create continuous data then field sampling and observations is very common practice, such as water sampling for quality analysis. But during this field sampling process, it is nearly impossible to collect data from each and every spot of field, usually samples collected at certain distance. So this distance gap/interval between two samples/more samples is not possible to cover as well as very tedious and time consuming. In this case, some representative samples such as water samples from all well locations or pollution parameters from air monitoring stations will be collected and interpolation method is deployed to create continuous layer. Accuracy of interpolated spatial data depends upon the quantity and spatial distribution …

Digital Image Processing-Introduction to Image Classification

IntroductionClassification is a simple process to categorize or sorting of data based on defined categories or criteria. Such as students in class can be categorized based on marks obtained in maths- number of student below 40%, number of students between 40-60%, number of students between 60-80% and number of students having more than 80%. So based on this criteria student can be categorized or sort in to four different class/category. This is a very simple and basic approach of classification to understand behavior of data in quantitative and qualitative both ways. 
This classification approach is used to classify satellite image. in the satellite image classification process, images are classified based on categorization and classification of pixel values present in satellite image. The pixel value present in each pixel is also called DN values (Digital Number), which is representation of reflectance values received by sensor of earth surface feature. It is already explained in prev…

Application GIS and Remote Sensing in Wetland Mapping-Case Study

Remote Sensing and GIS in Wetland MappingWetland mapping provides useful and important information for assessment of water resources and also for conservation and management of wetland. Remote Sensing and GIS techniques have huge potential for mapping, monitoring and assessment of wetland resources. There are better options to the users for wetland mapping, due to advancement in remote sensing and GIS technologies. As variety of remote sensing images are available with better and finder spatial and temporal resolution. As well as stereo satellite images are also available for effective and accurate mapping and estimation. These high resolution and stereo images can be used to wetland database and integrated with GIS for further analysis such as change simulation, scenario based predictions for better planning and monitoring.  Wetland Mapping Process through Remotely Sensed Images In the study the wetlands of Rajasthan falling in different ecological regions ranging from humid to hot ar…

Remote Sensing Application in Wetland Mapping

Inland Wetland Environment Wetlands refer to lowlands covered with shallow and sometimes temporary or intermittent waters. Wetlands include marshes, swamps, bogs, wet meadows, potholes, shallow lakes and ponds. However deep lakes, reservoir and permanent waters of streams are not considered as Wetlands. Hence we can say wetlands are transitional lands between terrestrial and aquatic systems where the water table is usually at or near the surface.  Importance of wetlands Wetlands posses a great ecological significance in terms of, net primary production, micro-climatic control, ground water recharge and habitat to large number of flora and fauna. It also plays a vital role in nutrient recycling and storage as well as biodiversity conservation. Wetlands help to retain water during dry periods, thus keeping the water table high and relatively stable. Threats to wetlands Rapidly expanding human population, large scale changes in land use, different development projects and improper use of w…