- June 30, 2020
Remote Sensing in Soil Mapping
RemoteSensing in Soil Mapping
Remotesensing is a technique of locating information of an object oroccurrence of something without making contact with the object. It isextensively used in areas such as geography or earth sciences, armystudies, intelligence and humanitarian applications. In the modernusage, it is mainly referred to as satellite imagery or air basedsensor tools that identify and classify objects on Earth includingsurface soils and the atmosphere (Barret et al 2013). Remote sensingcan be grouped into active remote sensing (satellite imagery) i.e.when a signal is emitted by an aircraft and its reflection by theobject is detected by the sensor and inert or passive remote sensing(aerial photography) i.e. when the reflection from the sun is sensedby the sensor.
Satelliteimageryit emits energy so that objects can be scanned in regions a sensorcan locate and determine the radiation that is reflected from thetarget. The LiDAR and Radar are the major examples of satelliteimagery remote sensing. Additionally, the time interruption betweenthe radiation and return is measured, developing the location,velocity and bearing of an object. The remote sensing images acquiredfrom the earth interpretations make it easy to understand the effectsof the atmosphere. A satellite image encompasses of a two-dimensionalarray of particular picture elements termed as pixel arranged incolumns and rows that represent an area of the Earth’s surface.
Theintensity of a satellite image is the measured quantity with thevalue which is typically the average value for the whole ground areacovered by the pixel. Similarly, a high-resolution image is one witha small resolution size. Notably, finely detailed images of objectscan be detected in a high resolution, for instance, they producevisible borders of soil types where the multispectral scanner sensor(MMS) obtains the imagery of the earth surface it provided a uniqueview of the land and marked the first digital remote sensing productsto the earth science department.
Theremote sensing techniques have assisted in monitoring remote groundcharacterization and management. These remote control methods act asthe basis for tracking. The satellite imagery can map, analyzesurface wetness, moisture, relief, moist surfaces and vegetativecover. In this case, the knowledge of soil surface status especiallyforest soils, urban soils and farmland soils is useful inunderstanding some physio-chemical properties of the soils. The soilreflectance may enhance the clarification of satellite imagery(Lillesand et al 2014).
Theground mapping demand has increased digital soil technology. Remotelysensed images could assist in mapping spatial designs of bare soilsand the spectral signature offer first-hand information on the top ofbare soils, hence visible boundaries of soil types can be mappedquickly. Additionally, forestsoilmoisture is often determined by Rader technology the soil contentprimarily refers to water available in the top part of soil.
Withspectral resolutions, data can be obtained about crop health in thatdetermination of bright green health leaves will have a unique anddifferent type of wavelengths, therefore, by using satellite imagery,it is easy to access the issues affecting the farmlandoperations and the necessary remedies to the affected regions. Theradiometric resolution can be used to help farmers increase the imagequality, correctness and readability for aerial photographs and scanscan be well implicated. On the other hand, the temporal resolutionscollect shorter information hence giving more detailed designs asthey are associated with soil nutrients, moisture and cropinfections.
Aerialphotography isthe film or aerial photography is a good example of passive remotesensors that collects radiations that are emitted or reflected by anobject or surrounding region. The reflected sunlight is the majorsource of radiation. It is also the taking of photographs of theearth surface from a staright down position aircraft or drones areusually used. It provides aerial photos that determine land-use andenvironmental conditions among many other uses.
Theaerial photographs are excellent sources of information for someprojects that need spatial data from the same area over a givenperiod. Additionally, the aerial photographs display a great extentof radial distortion and allow intensive study of major types ofsoils. The aerial photographs provide enhanced vantage points andimprove long-term recording. Technological remote sensing hasenormously used aerial photographs to provide a broad spectralsensitive spatial resolutions and geometric reliability than anyother ground-based sensing techniques (Nagendra et al 2013).
Theadequate knowledge about the properties and distribution of soils isthe critical issue that enhances viable environmental management. Thefertility management, crop selection and hydrological applicationshave facilitated the natural resource research studies. It givespossibilities for advancing soil data collections that analyze andderive soil properties. Furthermore, the remotely sensed imagery canbe used as a data source supporting digital soil mapping. Also, themajor research efforts have been made for mapping urbanlandscapesat various spatial resolutions. It is illustrated that models,designs and image analysis systems in urban remote sensing havesignificantly been developed.
Applicationor Remote Sensing Technology
Theremote sensing technique process remote data and are associated withgraphics software which enables the production of geographical orenvironmental information from satellites and aerial sensor records.The generation of information and specialized file formats thatcontain sensor imagery. The determination of the changes from imagestaken at varied times of then same region can be achieved. The mostcommon and visible sensors capture the spectra emissions whichsupport decision makers to define appropriate interventions ofenvironmental management (Nagendra et al 2013).
Remotesensing is based on the principle of inverse actions, where thephenomenon is not directly measured hence the quality of dataprocessed may contain spatial, spectral or temporal resolutions.First, the spectral resolution has a wavelength of differentfrequency sets collected and is linked to the total frequency of theitem or phenomenon.it may include some infra-red rays ranging from aspectral sensor. Second, the topographic or terrain modification inmountains may adequately light up the remote sensing images.
Theaerial photographic collection which is helpful in spatialmeasurement by the use of light platforms makes the dimensions ofobjects to be known so that alteration can be recognized. Similarly,data obtained from remote sensing is essential in providing a durablerecords for a broad geography. The aerial traffic control, timelyalerts and large scale data can be retrieved this Radar data isnecessary for monitoring velocity limits that measure sea levels,wavelengths and tides. Finally, data obtained define theconcentration of the existing chemical in the atmosphere.
Lillesand,T., Kiefer, R. W & Chipman, J. (2014). Remote sensing and imageryunderstanding. John Wiley & Sons.
Barrett,E. C. (2013). Introduction to environmental remote sensing.Routledge.
Nagendra,H., Lucas, R., Honrado, J., Jongman, R.& Mairota, P. (2013).Remote sensing technology for maintenance monitoring: Assessingprotected areas, habitat extent, habitat condition, speciesdiversity, and threats. Ecological Indicators.