Modeling Soil Processes: Review, Key Challenges, and New Perspectives

Abstract

The remarkable complexity of soil and its importance to a wide range of ecosystem services presents major challenges to the modeling of soil processes. Although major progress in soil models has occurred in the last decades, models of soil processes remain disjointed between disciplines or ecosystem services, with considerable uncertainty remaining in the quality of predictions and several challenges that remain yet to be addressed. First, there is a need to improve exchange of knowledge and experience among the different disciplines in soil science and to reach out to other Earth science communities. Second, the community needs to develop a new generation of soil models based on a systemic approach comprising relevant physical, chemical, and biological processes to address critical knowledge gaps in our understanding of soil processes and their interactions. Overcoming these challenges will facilitate exchanges between soil modeling and climate, plant, and social science modeling communities. It will allow us to contribute to preserve and improve our assessment of ecosystem services and advance our understanding of climate-change feedback mechanisms, among others, thereby facilitating and strengthening communication among scientific disciplines and society. We review the role of modeling soil processes in quantifying key soil processes that shape ecosystem services, with a focus on provisioning and regulating services. We then identify key challenges in modeling soil processes, including the systematic incorporation of heterogeneity and uncertainty, the integration of data and models, and strategies for effective integration of knowledge on physical, chemical, and biological soil processes. We discuss how the soil modeling community could best interface with modern modeling activities in other disciplines, such as climate, ecology, and plant research, and how to weave novel observation and measurement techniques into soil models. We propose the establishment of an international soil modeling consortium to coherently advance soil modeling activities and foster communication with other Earth science disciplines. Such a consortium should promote soil modeling platforms and data repository for model development, calibration and intercomparison essential for addressing contemporary challenges.

Stress Coefficients for Soil Water Balance Combined with Water Stress Indicators for Irrigation Scheduling of Woody Crops

“…According to Šimůnek et al [84], some of this work was developed following earlier research on the unsaturated soil hydraulic conductivity combined with an equation for the soil water retention curve to yield relationships that were incorporated in numerical simulators and software packages, like HYDRUS. Green et al [3] and Vereecken et al [85] discussed the application of this and many other models that become more comprehensive and numerically accurate to solve theoretical and practical problems, serving an important role in vadose zone research [86].…”

“…Vereecken et al [85] presented a discussion of the aspects that require development within the general context of modelling soil processes. Up to now, many models include nonstandard modules only in an approximate manner and without sufficient documentation.…”

Identifying the future water and salinity risks to irrigated viticulture in the Murray-Darling Basin, South Australia

“…There is a large number of models (e.g., https://soil-modeling.org/ resources-links/model-portal/model-collection; Vereecken et al, 2016) that have been used in similar studies as ours. All these models have their own pros and cons depending on their capabilities of addressing climate, soil, and crop variables for the future climate.…”

The HPx software for multicomponent reactive transport during variably-saturated flow: Recent developments and applications

“…Mathematical, process-based simulation models are indispensable tools for elucidating the role of coupled processes in soil systems, including their functioning and providing ecosystem services (Vereecken et al, 2016). Coupled multicomponent reactive transport models for the so-called critical zone (Brantley et al, 2007) are essential tools to analyze nonlinear interactions between hydrological, geochemical and (micro)biological processes and to link the critical zone to other spheres of the earth system such as the hydrosphere, atmosphere, biosphere, and geosphere (Li et al, 2017;Steefel et al, 2005).…”