Linking External Components to a Spatio-temporal Modelling Framework: Coupling MODFLOW and PCRaster

Environmental Modelling & Software, Volume 24, Issue 9, September 2009, Pages 1088-1099

O. Schmitz, D. Karssenberg, W.P.A. van Deursen, and C.G. Wesseling

“An important step in the procedure of building an environmental model is the transformation of a conceptual model into a numerical simulation. To simplify model construction a framework is required that relieves the model developer from software engineering concerns. In addition, as the demand for a holistic understanding of environmental systems increases, access to external model components is necessary in order to construct integrated models.

“We present a modelling framework that provides two- and three-dimensional building blocks for construction of spatio-temporal models. Two different modelling languages available in the framework, the first tailored and the second an enhanced Python scripting language, allow the development and modification of models. We explain for both languages the interfaces allowing to link specialised model components and thus extending the functionality of the framework. We demonstrate the coupling of external components in order to create multicomponent models by the development of the link to the groundwater model MODFLOW and provide results of an integrated catchment model. The approach described is appropriate for constructing integrated models that include a coupling of a small number of components.”

An Investigation on the Distribution of Eight Hazardous Heavy Metals in the Suburban Farmland of China

Journal of Hazardous Materials, Volume 167, Issues 1-3, 15 August 2009, Pages 1246-1251

Pingguo Yang, Renzhao Mao, Hongbo Shao, Yunfeng Gao

“Understanding spatial variability of hazardous soil heavy metals is an important precondition for suitably monitoring and evaluating eco-environment quality in the primary agricultural production zone. One hundred topsoils were sampled from the urban–rural transition zone in Taihang Piedmont Plain, China. The contents of eight heavy metals Cu, Zn, Cr, Ni, Pb, Cd, Hg and As were tested for each soil sample, and their spatial patterns were analyzed by the semivariogram approach of geostatistics and geographical information system (GIS) technology. Results showed that Cd concentration exceeded its background level. The local pollution from Cd attributed to the anthropogenic influence. The concentrations of eight hazardous heavy metals are relatively lower than the critical values of the national soil quality standard. The correlation distance of soil heavy metals ranged from 3.28 to 11.63 km, with the eight heavy metals having moderate spatial dependence. Cu, Cr, Ni, Pb and As are associated with and controlled by parent material. The results are helpful for improving agricultural and forest ecosystem in the arid and semiarid region.”