Biochar Alters Soil Physical Characteristics, Arbuscular Mycorrhizal Fungi Colonization, and Glomalin Production

Abstract

Soil enhancements such as biochar (BC) are gaining attention as tools to mitigate climate change and also to promote crop growth. However, biochar use can disrupt soil ecosystems by changing the soil’s physical, chemical, and biological properties. The study aimed to determine how biochar influences soil physical changes such as specific surface area (SSA) and water vapor sorption, and how these conditions affect arbuscular mycorrhizal fungal (AMF) hyphae growth and glomalin production. The study analyzed these factors at different plant phenological phases (i.e., flowering, development of fruit, and ripening of fruit and seed) to better understand the changes within the system while varying biochar amounts. The study also investigated the effect of different soil physical and chemical parameters on mycorrhizal hyphae growth and glomalin production. Four treatments were investigated: 0, 0.5%, 2.5%, and 5.0% (w/w) biochar amended silt loam soil planted with pepper. Soil samples were taken at the beginning and weeks 6, 10, and 12 of the study. The amount of adsorbed water vapor increased with an increasing amount of biochar added to the soils. Compared to control, SSA was significantly higher in all biochar amended treatments based on adsorption data, and only in the highest biochar amended soils for the desorption data at the end of the experiment. The presence of AMF in the roots appeared at week 6 of the experiment and the intensity of AMF root colonization increased with the age of plants. The AMF colonization parameters were significantly lower in BC2.5 compared to all other biochar amended soils. The abundance of intraradical AMF structures was highly correlated with several physicochemical soil parameters, such as SSA, the geometric mean diameter of soil aggregate, soil aggregate sizes, or pH. Glomalin production was negatively correlated with SSA, water vapor adsorption, aggregate stability, aggregate size, total nitrogen, potassium, and organic carbon content of the soil, while positive correlation was observed with bulk density. Increased biochar amount resulted in a significant decrease in glomalin production, concurrent with the age of the plants. Our results highlight the great complexity of interactions between soil physicochemical and biological parameters, and the importance of the time of sampling when biochar is used in soil, as the effects of biochar additions on the plant, soil physical characteristics, and soil microsymbionts vary over time.

Contemporary Approach to the Porosity of Dental Materials and Methods of Its Measurement

“…In turn, the CO 2 method is frequently used to measure the structure of micropores and narrow constrictions with widths smaller than 2 nm, due to the greater kinetic energy of the molecules and speeding diffusion into the narrow pores [104,108,109]. Other alternatives for N 2 method include krypton (at 77 K) [110], helium (at 4.2 K) [111], or the adsorption of polar liquids, such as water vapour (at 293 K) [112]. The use of water vapour allows for the assessment of the so-called internal surface area, pore size distribution, and the interaction with polar surface functional groups that constitute adsorption sites for water vapour molecules [113][114][115].…”

Exogenous Glomalin-Related Soil Proteins Differentially Regulate Soil Properties in Trifoliate Orange

“…GRSP can attach to the outside of soil aggregates and reduce the loss of soil, water, and nutrients [14]. In addition, glomalin can enter the soil with the degradation of extraradical mycelium, which in turn plays a very important role in improving the organic carbon sequestration and soil properties [15]. It is documented that GRSP promotes the formation and stability of soil aggregates, in addition to improving soil and plant water relations [14,16].…”

Changes in the Soil–Plant–Water System Due to Biochar Amendment

“…The type of biochar is also an important aspect of these types of studies. The biochar used in the present study is known to increase the specific surface area of the soil, which might enhance plant available water and water retention of the soils [13]. However, the increases in soil porosity and surface area for the investigated biochar amended maize parcels were not sufficient to result in improved crop yield.…”

“…Soil water dynamics can influence soil chemistry, for example by increasing nutrients leaching off the root zone, where nutrient limitations in soils can affect plant growth and health. Biochar also affects soil physical properties, such as through increased aggregate stability, porosity, and bulk density [11][12][13], which can influence soil moisture levels and, consequently, the available water for plants. Biochar use can cause increased yield production of maize or other crops, which might result from the improved soil conditions of soil moisture [4,14], reduced bulk density [15], or specific soil chemical and biological parameters [13,16].…”

“…Biochar also affects soil physical properties, such as through increased aggregate stability, porosity, and bulk density [11][12][13], which can influence soil moisture levels and, consequently, the available water for plants. Biochar use can cause increased yield production of maize or other crops, which might result from the improved soil conditions of soil moisture [4,14], reduced bulk density [15], or specific soil chemical and biological parameters [13,16]. However, biochar amendment alone cannot guarantee increased maize production [17]; therefore, continuous plant response measurements to soil amendments might provide us with a better understanding of the influencing factors derived from the changing environmental conditions.…”