Blueberry farming is one of Maine largest economic export. The blueberries are native to Maine and have adapted to the soils acidic and low fertility capacity. The purpose of this investigation is to see the land use changes that has possibly occurred over time and impact of blueberry farming on land in Maine. Has the barren which are the areas were these blueberry farming is practiced increased? Has this increase if any affected land use for other services such as water ways? To help us we will use Remote sensing tool which is the Landsat Imagery and work with it in a GIS station. Landsat 5 is a low earth observation satellite whose mission is to collect raw imagery from the land surface. It started its mission in 1984 and was used to collect over 2.5 million images at an orbit of 705 km. it had a transmission band width of 85Mbit/s. it takes 16 days to complete its orbit. It has seven spectral bands with a thematic mapper and multi spectral scanner features. For this exercise we imported Landsat imagery from 1999 and 2010 into an ArcGIS workstation. We then modified certain elements of the imagery to enable us understand changes to the earth surface on the location, the blue berry barren changes between 1999 and 2010.
To help us in the land detection investigation; I took data available from land sat 5 imagery and imported into the GIS workstation; the data were from 1999 and then a second one from 2010. The next step was to normalize the imagery to enable us make comparisons; this involves converting digital number values present in each pixel and converting them to radiance and then again to reflectance. In the digital number to radiance conversion the map algebra function of the ArcGIS was used and the input was the equation of converting digital number to radiance;
Lλ = (LMAXλ – LMINλ) / (QCALMAX-QCALMIN))*(QCAL-QCALMIN) + LMINλ
L is the spectral radiance while LMAX and LMIN represents the highest and lowest possible values of radiance which varies with gain state.
QCALMAX AND QCALMIN represents the calibrated maximum and minimum cell values. QCAL is the digital number or the cell values to be recalibrated and it specifies the target band. Also I used a different value for LMAXλ and LMINλ in each band. At the end of this conversion the next step was to convert radiance to reflectance. Atmosphere reflectance is a normalized unitless measure of the ratio of the amount of light energy reaching the earth surface to the amount of light bouncing off the surface and returning to the top of the atmosphere to be detected by sensors. Reflectance calculation is given as; Pλ=π*Lλ*d2 / ESUNλ*cosƟs
The Lλ IS the spectral reflectance at the sensor aperture, the variable d is the distance from the earth surface to the sun in astronomical units (AU). ESUNλ is the mean solar exo atmospheric irradiance. It also used as the mean amount of light of a particular band making its way to the sensor from the space without...