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54 Soil Moisture

national Journal of Remote Sensing. 2004;25:3593-3623

The advantages that offer new techniques such as remote sensing to estimate soil moisture require local accurate measurements of this variable since these values are key to validate the estimated ones. The chapter analyses the performance to measure soil moisture using different sensors that correspond to different scales at the field. Sensors used were based on reflectometry, time and frequency, which were calibrated with gravimetric measurements. Additionally to have accurate soil moisture values, the idea is to have an operational system in a very complex ecosystem in order to see its influence to maintain the aguadas (small natural lagoons) at the south of the Yucatan Peninsula. These aguadas represent an important source of water in the region because the area presents shortage associated not only with the climate variation but also with high influence due to the type of soils (karst). Results demonstrated that the sensors tested were accurate particularly in the rainy season with some differences in the dry period, and also, the sensitivity of each device was determinant. Results will cover different areas from point to small regions (<4 km), since soil moisture data obtained could be extrapolated to different scales based on the climate, vegetation and type of soil, to compute the real water availability for the communities in the zone.

**Keywords:** soil moisture, DTR, FDR, aguadas, water availability

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, © 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

distribution, and reproduction in any medium, provided the original work is properly cited.
