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Tillage practices can affect the long term sustainability of agricultural soils as well as a variety of soil processes that
impact the environment. The benefits of reduced tillage and no-till practices over agriculture fields are well documented
and include: (1) significant reductions in wind and water erosion mitigating nutrient and pesticide runoff into waterways;
(2) increasing and/or maintaining soil organic matter; (3) increasing biological activity and improving soil structure; and
(4) increasing soil carbon and its sequestration. Information on tillage activities assists in implementing policies and
programs to promote beneficial management practices (BMPs), and in monitoring the success of these initiatives.
Agriculture and Agri-Food Canada supports environmentally responsible agriculture and has identified this as one of
their priorities. Thus, tillage information requirements have become increasingly important to a number of programs and
policies within the department.
Rapid, accurate and objective methods are required to map and monitor tillage activities. Earth observing satellites can
assist with targeting and monitoring land management activities. For the last decade, research has clearly demonstrated
that complementary information provided by both optical and radar satellite sensors are fundamental in developing an
agricultural land management monitoring system. Launched in June 2007, the TerraSAR-X is a radar satellite acquiring
data at the X-band frequency (9.6 GHz). The application of TerraSAR-X data for conservation tillage mapping has been
somewhat limited, and thus this study investigates its use in determining tillage occurrence. An HH-HV TerraSAR-X
image was acquired on November 4, 2009 and ground data were also collected characterizing tillage conditions at the
time of acquisition. Backscatter responses were analyzed to identify tillage occurrence and to differentiate between
untilled, chiseled and moldboard ploughed fields. Preliminary analysis showed that HH polarization can better contribute
to tillage discrimination than compared to HV polarization and that the backscatter response can be used to discriminate
untilled fields from ones that are moldboard ploughed. However, chiseled fields were often confused with highroughness
(rms height~1.30 cm) untilled fields and moldboard ploughed fields. Fully polarimetric X-band radar datasets could potentially contribute more information to mapping tillage conditions.
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