Search results for "Soil Moisture"
showing 10 items of 74 documents
The CoSMOS L-band experiment in Southeast Australia
2007
The CoSMOS (Campaign for validating the Operation of the Soil Moisture and Ocean Salinity mission) campaign was conducted during November of 2005 in the Goulburn River Catchment, in SE Australia. The main objective of CoSMOS was to obtain a series of L-band measurements from the air in order to validate the L-band emission model that will be used by the SMOS (Soil Moisture and Ocean Salinity) ground segment processor. In addition, the campaign was designed to investigate open questions including the Sun-glint effect over land, the application of polarimetric measurements over land, and to clarify the importance of dew and interception for soil moisture retrievals. This paper summarises the …
Remote sensing data for crop yield in CONUS
2023
I) SUMMARY This database contains harmonized time series for the study of crop yields using remote sensing data and meteorological data. We collected information on soybean, corn, and wheat yields (t/ha) over the CONUS (continuous US) from USDA-NASS for years 2015–2018 at a county level, and collocated time series for the following variables: Enhanced Vegetation Index (EVI) from MODIS satellite (MOD13C1 v6 product) Soil Moisture (SM) from SMAP satellite through MT-DCA algorithm Vegetation Optical Depth (VOD) from SMAP satellite through MT-DCA algorithm Maximum temperature (TMAX) from Daymet v3 Precipitation (PRCP) from Daymet v3 II) CONTACT For questions, please email Laura Mart&iacut…
Responses of apple to partial root-zone drying. A review.
2013
Partial root-zone drying (PRD) is a relatively recent strategy aiming at substantial reduction of irrigation volume. It consists of the alternate irrigation of one portion of the root-zone with volumes reduced to about 40-50% of conventional water. PRD is based on the ability of roots in drying soil to produce hormonal signals, like abscissic acid (ABA), responsible for partial stomatal closure. In turn, partial stomatal closure would improve water use efficiency and increase fruit yield per unit of irrigation water. This technique has been tested on a number of fruit crops, including apple. In addition to climatic conditions, which mainly affect atmospheric water demand, soil properties an…
A New Calibration Equation for Diviner2000 Capacitance Probe Accounting for Soil Shrinkage Characteristic Curve and Estimation of Parameters on the B…
2014
Real-time measurements of soil water status are quite often used for irrigation scheduling and particularly in precision irrigation, in order to identify the exact timing and amount to supply to crops according to their water requirements. Diviner2000 capacitance probes, measuring the apparent soil dielectric permittivity, have been extensively used in the last decade. Several studies have shown that, for different soils, there is a relationship between the volumetric soil water content (SWC) and the scaled frequency (SF) measured by the sensor. However, for swelling/shrinking clay soils, for which bulk density changes with soil water content, there is a lack of knowledge on how these varia…
Indirect estimation of calibration equation parameters for Sentek Diviner 2000 capacitance probe by means of soil physical properties
2014
Measurements of soil water content (SWC) are often used for irrigation scheduling. Accurate monitoring of SWC is necessary, for example, to identify the exact irrigation timing and the amount of water volume to supply according to the crop requirement. The use of capacitance probes, measuring the apparent soil dielectric permittivity, indirectly related to soil water status, have been increasing during the last decade, as proved by the numerous researches carried out to determine, for different soil types, site-specific calibration relationships between SWC and the scaled frequency (SF) measured by the sensor. However, for swelling/shrinking clay soils, there is a lack of knowledge on how t…
Subsurface drip irrigated potato (Solanum tuberosum L.) with saline water under Tunisian climate
2012
Field experiment was conducted at the Higher Institute of Agronomy of Chott Meriem (Tunisia) during the growing season (2011/2012) to investigate the effects of water quality on water‘s dynamic in soil (water potential, soilcmoisture distribution, water’s stock in soil) and water use efficiency (WUE) to produce potato (Solanum tuberosum L.). Irrigation management treatments were fresh (1 dS m-1) and saline waters (4 dS m-1). Subsurface drip irrigation was used, a rate of 4 L h-1 applied at the same irrigation duration and interval. The results indicate that water content is more uniform using the saline water varies from 15 to 23% than treatment varies from 10 to 26%. The recorded changes o…
Synergistic integration of optical and microwave satellite data for crop yield estimation
2019
Developing accurate models of crop stress, phenology and productivity is of paramount importance, given the increasing need of food. Earth observation (EO) remote sensing data provides a unique source of information to monitor crops in a temporally resolved and spatially explicit way. In this study, we propose the combination of multisensor (optical and microwave) remote sensing data for crop yield estimation and forecasting using two novel approaches. We first propose the lag between Enhanced Vegetation Index (EVI) derived from MODIS and Vegetation Optical Depth (VOD) derived from SMAP as a new joint metric combining the information from the two satellite sensors in a unique feature or des…
SENTINEL-1 for wheat mapping and soil moisture retrieval
2015
The main objective of this study is to assess the use of Sentinel-1 (S-1) data for surface soil moisture (SSM) retrieval and wheat mapping (WM) at high spatial resolution (e.g. 100–500m), which constitute valuable information for improving crop yield forecast at large scale. A knowledge based classification method and a SSM retrieval algorithm, developed in view of the European Space Agency Sentinel-1 mission, have been applied to a time series of S-1A data collected from October 2014 to April 2015 over a well-documented agricultural site in southern Italy. In particular, observations of SSM content recorded by a network of ground stations deployed in an experimental farm have been used to …
Spatial Distribution of Soil Hydrological Properties in the Kilombero Floodplain, Tanzania
2017
Analysis and interpretation of soil properties dynamics is a keystone in understanding the hydrologic responses and yield potential of floodplain wetlands. This study characterizes the distribution and spatial trends of selected soil physical properties in the Kilombero floodplain, Tanzania. A total of 76 composite soil samples were taken from 0 to 20 cm and 20 to 40 cm depth in a regular grid design across three hydrological zones, related to flooding intensity defined as fringe, middle, and riparian during the rainy season of 2015. The samples were analyzed for soil texture, bulk density, organic carbon, and saturated hydraulic conductivity. Seasonal soil moisture content was monitored at…