Modeling of Phosphorus Loads in Sugarcane in a Low‐Relief Landscape Using Ontology‐based Simulation

Abstract

Water flow and P dynamics in a low-relief landscape manipulated by extensive canal and ditch drainage systems were modeled utilizing an ontology-based simulation model. In the model, soil water flux and processes between three soil inorganic P pools (labile, active, and stable) and organic P are represented as database objects. And user-defined relationships among objects are used to automatically generate computer code (Java) for running the simulation of discharge and P loads. Our objectives were to develop ontology-based descriptions of soil P dynamics within sugarcane- (Saccharum officinarum L.) grown farm basins of the Everglades Agricultural Area (EAA) and to calibrate and validate such processes with water quality monitoring data collected at one farm basin (1244 ha). In the calibration phase (water year [WY] 99-00), observed discharge totaled 11,114 m3 ha(-1) and dissolved P 0.23 kg P ha(-1); and in the validation phase (WY 02-03), discharge was 10,397 m3 ha(-1) and dissolved P 0.11 kg P ha(-). During WY 99-00 the root mean square error (RMSE) for monthly discharge was 188 m3 ha(-1) and for monthly dissolved P 0.0077 kg P ha(-1); whereas during WY 02-03 the RMSE for monthly discharge was 195 m3 ha(-1) and monthly dissolved P 0.0022 kg P ha(-1). These results were confirmed by Nash-Sutcliffe Coefficient of 0.69 (calibration) and 0.81 (validation) comparing measured and simulated P loads. The good model performance suggests that our model has promise to simulate P dynamics, which may be useful as a management tool to reduce P loads in other similar low-relief areas.

Soil Phosphorus Landscape Models for Precision Soil Conservation

“…Several studies have estimated and modeled P loadings to show P dynamics and budget in Florida. For example, Kwon et al (2010) used measured and modeled P loads and found dissolved P values from 0.23 kg ha −1 (1999–2000) to 0.11 kg ha −1 (2002–2003) in farm basins in the Everglades Agricultural Area in Florida. The decreasing P loads were attributed to the implementation of best management practices.…”

A Knowledge Management Approach to the Loosely Coupled Systems

“…Such relation between the numerical and semantic components enables smooth dynamical interaction that provides constant record analysis of the ongoing evolution. Beside as-is analysis, we can use the dynamic knowledge mapping to create to-be ontology based simulation model compared to the modelling solution of Kwon et al (2010). With the possibility to predict the knowledge network patterns we extend our analytical ability not only to evaluate past or current states of the organizational system, but also to determine which knowledge network patterns should be encouraged to improve work processes in the system.…”

Ontology-Based Wastewater Best Management Practices Recommendation

“…Ontology can be used to support large complex model, especially concerning lots of different domain experts [3]. Substitute it for traditional numerical model also makes good result [4,5,6,7]. The feature with ontology modeling is that anyone can use the knowledge of their own to create and run model, but not to know how to program.…”