This research was conducted to develop relationships among evapotranspiration (ET), percolation (PERC), groundwater discharge to the stream (GWQ), and water table fluctuations through a modeling approach. The Soil and Water Assessment Tool (SWAT) hydrologic and crop models were applied in the Big Sunflower River watershed (BSRW; 7660 km(2) ) within the Yazoo River Basin of the Lower Mississippi...

Thinking at plant architecture as emerging from a simple set of construction rules is a very appealing feature of L-Systems. In the context of crop modeling, it opens new ways to model the effects of environmental stresses on crop architecture, by pointing to regulation loops that are ignored in usual models (Fournier et al., 2007). As such, the triggering of leaf development by emergence event...

This paper proposes a density ratio estimator of crop yield distributions, wherein the number of observations for individual distributions is often quite small. The density ratio approach models individual densities as distortions from a common baseline density. We introduce a probability integral transformation to the density ratio method that simplifies the modeling of distortion functions. W...

Agbiotechnology uses genetic engineering to improve the output and value of crops. Altering the expression of the plant Type I Proton-pumping Pyrophosphatase (H+-PPase) has already proven to be a useful tool to enhance crop productivity. Despite the effective use of this gene in translational research, information regarding the intracellular localization and functional plasticity of the pump re...

Modeling of longitudinal data from agricultural experiments using growth curves helps understand conditions conducive or unconducive to crop growth. Recent advances in Geographical Information Systems (GIS) now allow geocoding of agricultural data that help understand spatial patterns. A particularly common problem is capturing spatial variation in growth patterns over the entire experimental d...

Influences of daily weather extremes, such as maximum/ minimum temperatures, humidity, and precipitation, are observable in perennial crop phonology that in turn determines the annual crop yield in quality and quantity. In viticulture, grapevine phonology determines the quality of vintage produced from the grapes apart from the best effects by winemaker. Following a brief review of current lite...

Lack of basic knowledge about spatial and treatment varying crop response to irrigation hinders irrigation management and economic analysis for site-specific agriculture. One model that has been postulated for relating crop-specific economic quantities to irrigation is a quadratic response curve of yield as a function of irrigation. Although this model has far reaching economic interpretations ...

1. Abstract This paper presents a geostatistical approach to model uncertainty about the spatial distribution of soil properties and to propagate it through a crop model, allowing for incorporation of uncertainty in the choice of management scenarios (no lime, single-rate liming and site-specific lime applications to acidic field soil). The methodology involved modeling the uncertainty about wh...

Polarimetric decomposition techniques and inversion algorithms are developed and applied on the OPAQUE data set acquired in spring 2007 to investigate their potential and limitations for soil moisture estimation. A three component model-based decomposition is used together with an eigenvalue decomposition in a combined approach to invert for soil moisture over bare and vegetated soils at L-band...

Technological changes in agriculture tend to alter the mass associated with a segment or subpopulation of the yield distribution as opposed to shifting the entire distribution upwards. We propose modeling crop yields using mixtures with embedded trend functions to account for potentially different rates of technological change in different subpopulations of the yield distribution. By doing so w...