As one of soil dynamics properties, soil moisture content is an important factor of soil fertility which counts for much to crop growth situation and scientific irrigation management. A design plan of regional spatial variation of soil moisture measurement was introduced. Its main job includes the use of differential GPS technology for each sampling points in farmland, collecting data of high-p...

The accuracy of moisture content determination in grain from measurement of electromagnetic parameters is known to be dependent on the bulk density of the sample used for the measurement. Various means of limiting this effect have been considered in the past. This paper identifies various density-independent expressions developed for this purpose and compares their effectiveness in minimizing t...

This paper reports a study of algorithm development and testing for soil moisture retrieval for bare fields using L-band SAR imagery. First-order surface scattering models predict that the co-polarization ratio is sensitive to soil moisture but not to surface roughness. Our previous study indicated that the measurement of (Jvv / (Jhh at L-band is proportional to soil moisture. In this study, th...

The measurement and control of soil moisture are the key technologies of precision agriculture. In order to real-time detect soil moisture content faster and more accurately, a portable soil moisture sensor based on NIR spectroscopy was developed. With the sixty soil samples collected from a winter jujube orchard, a linear regression model was established. The determination coefficients of the ...

Differing from the structure of traditional parallel plate capacitive sensor a semi cylindrical capacitive sensor has been introduced in this present work to measure the soil moisture conveniently. Here, the numerical analysis method to evaluate the capacitance from the semi-cylindrical capacitive sensor is analyzed and discussed. The changes of capacitance with the variation of soil moisture o...

This paper presents a very accurate sensor for the measurement of the moisture of undisturbed soil samples. The sensor relies on accurate estimation of the permittivity which is performed independently of the soil type, and a subsequent calibration. The sensor is designed as an upgrade of the conventional soil sampling equipment used in agriculture--the Kopecky cylinder. The detailed descriptio...

The NASA Soil Moisture Active and Passive (SMAP) mission is dedicated to measurement of global soil moisture and boreal land surface freeze/thaw state [1]. The satellite will carry radar (active) and radiometer (passive) L-band instruments that will perform simultaneous and coincident measurements of the Earth’s surface. The combination of data from the two instruments will allow unprecedented ...

Synthetic Aperture Radar has shown its large potential for retrieving soil moisture maps at regional scales. However, since the backscattered signal is determined by several surface characteristics, the retrieval of soil moisture is an ill-posed problem when using single configuration imagery. Unless accurate surface roughness parameter values are available, retrieving soil moisture from radar ...

Understanding the spatial and temporal variations of soil moisture is crucial for the land surface processes and their management. Accurate estimation of spatial and temporal variations of soil moisture is important for various hydrological studies also. Recently, remote sensing techniques have been used to estimate soil moisture. Estimation of soil moisture by remote sensing techniques provide...

PURPOSE Dry axilla can sometimes be found among dehydrated older patients. In this study, we measured the axillary moisture and assessed it as possible marker for dehydration. METHODS Twenty-nine older patients admitted with acute medical conditions participated in this study. Dehydration was diagnosed by the calculated serum osmolality of greater than 295 mOsm/L. The moisture of axilla was m...