Medium Spatial Resolution

Landsat satellite TM features

The first Landsat satellite was launched in 1972; the most recent one, Landsat 7, was launched on the 15^th of April 1999. The Landsat programme is controlled by NASA, and the received images are processes by USGS (United States Geological Survey).

Landsat 5 was designed to have a life span of 5 years and is capable of collecting and transmitting up to 532 images per day. It is in a helio-synchronical orbit what means that it always passes by a certain place at the same time. Its total earth surface vision happens every 15 days what means 232 orbits.

The essential sensor on board the satellite is the Thematic Mapper (TM). Spatial and spectral resolutions of TM sensor are detailed herewith:

• Visible spectrum and infrared bands have a spatial resolution of 30 m (channels 1, 2, 3, 4, 5 y 7).
• Thermal infrared bands (channels 6L and 6H) are acquired with a 60 metre resolution.
• The new panchromatic band (channel 8) has 15 m of spatial resolution.

IRS satellite LISS-III, LISS-IV and AWiFS sensors features

The first Indian satellite of the IRS programme was the IRS-1C, launched in December 1995. The last one of them, IRS-P6 –also called Resourcesat-1- was launched in October 2003.

IRS-P6 transports three sensors: LISS-III, LISS-IV y AWiFS. They have the following spatial and spectral resolutions:

This satellite has a temporal resolution of 24 days and its images are suited for advanced applications in vegetable dynamic, crop production estimations as well as to support disaster administration and natural resources inventory.

Working with IRS and Landsat satellite sensors

Since 2007 the Guadalquivir River Basin District works for irrigation sensing and evaluation of the evaporation/transpiration through remote sensing techniques. The successful bidder for this Technical Assistance was Management Agency Agriculture and Fishing (AGAPA), under Facultative Direction from Hydrologic Planning Office from Basin District. In addition the project was participated by Andalusian Institute for Research and Training of Agriculture, Fishing and Ecologic Production in Córdoba (IFAPA) and the Sustainable Agriculture Institute IAS-CSIC, also in Córdoba.

The works developed has been as follows:

Classification of 260.000 ha of cultivation land in Sevilla, Córdoba and Huelva

Crops were classified in a total of 11 categories. Permanent ones (76.842 ha) were classified with data owned by CAP and non-permanent ones (183.162 ha) by remote sensing techniques. The percentage of successful result was 88 %.

Evaluation of real evaporation/transpiration of the crops

ET₀ ETO was obtained by interpolation of values measured by RIA (Agro climatic Information System) from IFAPA, by using the equation from Penman – Monteith. K_c was determined from red and near infrared bands of LANDSAT-5 satellite and from maximum K_c values for cultivation from FAO-56 Manual. K_e was calculated by a simulation of a soil hydric balance using meteorological and remote sensing data.

The results obtained, with a 30 x 30 metres, were the following ones:

Later on the useful rain (80% of the total rainfall) from the period March-September was subtracted from ET₀, thus calculating the irrigation needs.

Development of Remote Sensing Techniques for distinction between irrigation and dry land olive groves on lots owned by Oleoestepa Cooperative (Estepa, Sevilla).

In this part of the project there were substantial operative and methodological advances in respect to the “state of the art” at international level. Somehow the limitations that existing satellites impose on these techniques became obvious. The development of an operative system on the field will surely require aero-transported sensors, as in aeroplanes with no pilot with infrared cameras that are currently used by IAS-CSIC. This kind of work is considered of a great interest for the organization and in the future will have to be separated from the two previous ones, as they are so different both in concept and method.

The results obtained by the project, because of its quality and scope, can be called optimal and greatly useful for the determination of irrigation allocations.

Documents downloads

Name	Type	Link
Technical assistance for the detection and evaluation of irrigation evapotranspiration using remote sensing technology 2010
Preview of technical assistance for the detection and evaluation of irrigation evapotranspiration using remote sensing technology 2008-2009
Irrigation water use monitoring at watershed scale using series of high resolution satellite images
Spectral vegetation indices for benchmarking water productivity of irrigated cotton and sugarbeet crops
Technical assistance for the detection and evaluation of irrigation evapotranspiration using remote sensing technology 2007-2008