Simulation of Soil Temperature Dynamics with Models Using Different Concepts

Nándor Fodor,Renáta Sándor

doi:10.1100/2012/590287

Nándor Fodor, Renáta Sándor

Open Access

https://doi.org/10.1100/2012/590287

Copy DOI

Abstract

This paper presents two soil temperature models with empirical and mechanistic concepts. At the test site (calcaric arenosol), meteorological parameters as well as soil moisture content and temperature at 5 different depths were measured in an experiment with 8 parcels realizing the combinations of the fertilized, nonfertilized, irrigated, nonirrigated treatments in two replicates. Leaf area dynamics was also monitored. Soil temperature was calculated with the original and a modified version of CERES as well as with the HYDRUS-1D model. The simulated soil temperature values were compared to the observed ones. The vegetation reduced both the average soil temperature and its diurnal amplitude; therefore, considering the leaf area dynamics is important in modeling. The models underestimated the actual soil temperature and overestimated the temperature oscillation within the winter period. All models failed to account for the insulation effect of snow cover. The modified CERES provided explicitly more accurate soil temperature values than the original one. Though HYDRUS-1D provided more accurate soil temperature estimations, its superiority to CERES is not unequivocal as it requires more detailed inputs.

Highlights

Soil temperature (Tsoil) is one of the most important variables of the soil
Two soil temperature models using different concepts were compared in this study
The experimental results clearly showed that crop cover significantly influences the soil temperature dynamics of the upper soil layers

Summary

Introduction

Soil temperature (Tsoil) is one of the most important variables of the soil. It can significantly influence seed germination [1], plant growth [2], uptake of nutrients [3], soil respiration [4, 5], soil evaporation [6], and the intensity of physical [7], chemical [8, 9], and microbiological processes [10, 11] in the soil.Solar radiation and air temperature are the main driving forces determining the soil temperature which is influenced by numerous other factors such as precipitation, soil texture, and moisture content as well as the type of surface cover (plant canopy, crop residue, snow, etc.) [12]. Soil temperature (Tsoil) is one of the most important variables of the soil It can significantly influence seed germination [1], plant growth [2], uptake of nutrients [3], soil respiration [4, 5], soil evaporation [6], and the intensity of physical [7], chemical [8, 9], and microbiological processes [10, 11] in the soil. If soil temperature is not measured, several methods are available to calculate it using meteorological variables and other parameters. There are three types of soil temperature models [16]: (1) empirical models that are based on statistical relationships between soil temperature at some depth and climatological and soil variables (e.g., [17]); (2) mechanistic models that focus on physical processes (radiative energy balance as well as sensible, latent, and ground-conductive heat fluxes) to predict the upper boundary temperature and estimate the temperature of deeper layers with Fourier’s equation (e.g., [18]); (3) mixed empirical and mechanistic models that calculate the temperature of different soil layers based on physical principles of heat flow, but the boundary temperature at the soil surface must be provided empirically (e.g., [19])

Objectives

Methods

Results

Discussion

Conclusion