The 2012 drought was one of the most extensive drought events in half a century, resulting in over USD 12 billion in economic loss in the United States and substantial indirect impacts on global food security and commodity prices. An important feature of the 2012 drought was rapid development and intensification in late spring/early summer, a critical time for crop development and investment pl...

Two neural network algorithms trained by a physical vegetation model are used to retrieve soil moisture and vegetation variables of wheat canopies during the whole crop cycle. The first algorithm retrieves soil moisture using L band, two polarizations and multiangular radiometric data, for each single date of radiometric acquisition. The algorithm includes roughness and vegetation effects, but ...

soil compaction is a major problem in many parts of the world. the determination of soil compaction profiles requires fast sampling systems to keep pace with the change in soil moisture condition over time. soil cone penetrometers are commonly used for this purpose. a tractor-mounted soil cone penetrometer was designed and fabricated with multiple probes and the ability to determine cone index ...

Irrigated row-crop agriculture is contributing to declining groundwater in areas such as the Mississippi Delta region of eastern Arkansas. There is a need to move toward sustainable levels of groundwater withdrawal. Recent improvements in remote monitoring technologies such as wireless soil moisture sensors and unmanned aerial vehicles offer the potential for farmers to effectively practice sit...

Irrigated agriculture is dependent on an adequate water supply of usable quality. Water used for irrigation can vary greatly in quality depending upon type and quality of dissolved salts. Salts are present in irrigation water in relatively small but significant amounts. The problems that result very both and kind, degree and modified by soil, climate and crop. The aim this paper is to monitor t...

Crop coefficient values are used to estimate crop evapotranspiration (ETc) for determining irrigation scheduling. Many important crop biophysical properties such as Percentage Vegetation Cover and Leaf Area Index can be estimated from remotely sensed Vegetation Index, in order to quantify real time vegetation growth dynamics. The objective of this study was to understand the effectiveness of ba...

This study investigates temporal relationships between vegetation growth, rainfall, and soil moisture for six sites located in sub-Saharan and southern Africa for the period 2005-2009. Specifically, seasonal components of time series of Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) composites from the Moderate Resolution Imaging Spectroradiometer (MODIS) and ...

A field study was initiated in 1992 to investigate the long-term impacts of beef feedlot manure application (composted and uncomposted) on nutrient accumulation and movement in soil, corn silage yield, and nutrient uptake. Two application strategies were compared: providing the annual crop nitrogen (N) requirement (N-based rate) or crop phosphorus (P) removal (P-based rate), as well as a compar...