The effect of exogenous organic matter on the thermal properties of tilled soils in Poland and the Czech Republic

Abstract

Purpose Organic matter improves soil fertility and water and thermal properties, but its content often decreases. This decrease may be mitigated by the addition of exogenous organic matter (EOM). The aim of this study was to assess the effect of EOMs, including compost from manure, slurry, and straw (Ag); industrial organic compost from sewage sludge (Ra); animal meal from animal by-products (Mb); and digestate from a biogas fry factory (Dg) on soil thermal conductivity, heat capacity, thermal diffusivity, water content, and bulk density in the top (0-15-cm) layer of two soils in Poland and the Czech Republic. Materials and methods Irrespective of EOM type, the total yearly nitrogen application rate being 200 kg N ha −1 (100%) was from a given EOM at the rates 0, 50, 75, and 100% and the remaining parts from the mineral fertilizer. The study was conducted in 2013-2014 in Poland (Braszowice) and the Czech Republic (Pusté Jakartice) on loam silt and clay silt loam, respectively, as part of a cross-border cooperation project. The soil properties were examined using classical descriptive statistics, semivariograms, and kriging-interpolated maps. Results and discussion Analysis of linear regressions (trends) showed that the EOM application rate influenced (positively or negatively) the soil properties in most measurement occasions. The variability of all soil properties was low and medium (coefficient of variation 7.3-34%). Geostatistical analysis indicated that the spatial dependence (C 0 /(C 0 + C s)) of the soil properties on the EOM-amended plots was very strong or moderate. The maps revealed that the heterogeneity and degree of patch fragmentation were greater for thermal conductivity and heat capacity than for thermal diffusivity, water content, and bulk density. In general, all the soil properties were spatially more variable in the Braszowice than Pusté Jakartice soil and in spring than autumn in both sites. Conclusions The spatial analysis and maps enhance the comprehensive understanding of changes in soil thermal properties in response to EOM application. Suitability of the results from the field experiments in models predicting some thermal properties based on soil bulk density and water content in relation to EOM addition was indicated. Expressing the amount of EOMs added using the organic carbon content basis (% kg OC/kg of soil) instead of the nitrogen content basis allowed identifying areas on the kriging-interpolated maps where the distribution of soil thermal properties resembled that of soil organic carbon content, water content, and bulk density. Thus, the effect of EOMs on soil thermal properties is considered along with changes in soil water content and bulk density. The results will be helpful in forecasting effects of exogenous organic matter on the soil thermal properties affecting surfaceenergy partitioning, temperature distribution in soil, and plant growth.

Genetic and Metabolic Diversity of Soil Microbiome in Response to Exogenous Organic Matter Amendments

“…Exogenous organic matter (EOM) is defined as the whole of the OM that is introduced into the soil in order to improve its fertility, quality and the potential of the land for non-agricultural use [4,5]. EOM includes a very wide range of biowastes from various sources [6].…”

Effect of Long-Term Semiarid Pasture Management on Soil Hydraulic and Thermal Properties

“…For instance, Abu-Hamdeh and Reeder (2000) [ 75 ] reported a decrease in λ with increasing SOM, i.e., from λ of 0.33 W m −1 K −1 at 5% SOM to 0.17 W m −1 K −1 at 30% SOM. However, Usowicz and Lipiec (2020) [ 87 ] observed no clear trend in λ with an increasing application rate of exogenous SOM except for a few measurement dates. SOM content may indirectly affect thermal properties by altering soil aggregate structure [ 14 ], in which spherical soil aggregates tend to reduce λ and D t by changing contact areas, and by altering water storage [ 30 ], in which soil water mainly increases λ [ 76 ].…”

Impact of Three Soil Textures on the Fungal Community Structure in Rhizosphere Soils of Malus hupehensis Rehd. Seedlings

“…According to analyses, the soil characteristics of WL were relatively stable. Clay loam has low porosity, strong permeability and water retention (Reynolds et al, 2007), and relatively little loss of organic matter and mineral elements (Usowicz and Lipiec, 2020). This stable soil ecology has been shown to interfere with certain dominant flora (Franzluebbers et al, 1996).…”