Soil Aggregate Stability in Salt-Affected Vineyards: Depth-Wise Variability Analysis

Abstract

Soil aggregate stability is an ideal integrative soil quality indicator, but little is known about the relevance of such an indicator with soil depth for salt-affected soils. The objective of this study was to determine soil aggregate stability and identify preponderant aggregation factors, both in topsoil and subsoil horizons in salt-affected conditions. We conducted field investigations by describing soil profiles in pedological pits and by collecting soil samples from different field units. Soils were sampled within different soil horizon types, from superficial tilled organo-mineral horizons to mineral horizons. For all soil samples, we determined the mean weight diameter (MWD) as an indicator of soil aggregate stability and also determined associated physical and chemical properties in some samples. The measured MWD value from 0.28 mm to 1.10 mm could be categorised as unstable, with MWD values and variability decreasing drastically from the topsoil to the deepest mineral horizons. Analysis of MWD in relation to physical and chemical properties suggested that the variability in the MWD value of A-horizons was influenced by both clay fraction abundance and soil organic carbon (SOC) content and the nature of the agricultural practices, while at deeper B-horizons, the decrease in SOC content and the variability in other soil properties with soil depth could be used to explain the overall low aggregate stability. In this study, investigations of soil pits coupled with measurements of soil aggregate stability indicated that it could be possible to restore soil structure quality by limiting deep soil profile compaction in order to improve salt leaching and exportation.

Evaluation of Soil Physico-Chemical and Biological Properties under Different Tea (Camellia sinesis) Gardens of Himachal Pradesh, India

“…From the mean value of both surfaces, it was revealed that the the lowest value (25%) was recorded in Bhawarna, whereas the highest (56%) was recorded in Narghota, Higher water stable aggregates in soils might be due to higher organic matter content and enhanced microbial activity which secretes binding material during the decomposition process, giving rise to better structure and stable aggregates. The results were in consonance with the findings of Bless et al (2022) and Baker et al (2004).…”

Potassium Humate and Silicate Combined with Compost Application to Reduce the Harmful Effects of the Irrigation Water Salinity on Potato Plants and on the Soil Available Nutrient Npk

“…These results fall in line with findings of (Li et al, 2020) who found the same trend. These results could be due to soil salinity which increase aggregates of particles and decrease soil bulk density (Bless et al, 2022). F1 36.26 8.26 309.43 35.26 7.86 311.16 F2 41.16 12.17 321.33 41.25 11.83 331.66 F3 38.96 10.31 318.56 37.50 10.15 329.66 F4 33.38 9.85 303.66 31.66 9.07 309.33 F5 28.71 7.37 289.63 27.60 8.03 296.66 W2 F0 48.96 14.02 343.66 44.67 13.00 348.66 F1 35.5 10.84 318.33 34.53 10.19 324.43 F2 27.85 7.77 309.33 26.26 7.71 311.53 F3 28.70 8.91 313.00 27.20 8.25 313.83 F4 41.15 11.76 323.83 40.56 11.39 325.33 F5 43.06 12.06 335.80 41.56 11.79 336.00 W3 F0 55.15 13.50 376.66 52.75 13.10 377.00 F1 40.41 11.98 353.90 39.71 11.86 358.33 F2 28.95 8.90 347.33 27.57 8.86 348.33 F3 32.87 10.32 350.33 31.53 10.50 351.00 F4 46.92 12.05 360.86 44.85 12.13 370.33 F5 48.24 12.63 364.76 45.86 13.06 383.00 LSD at 0.05 2.0829 0.3908 2.0396 0.5892 0.5026 2.7474 W1= 0.5 dsm -1 , W2= 2.25 dsm -1 , W3= 5.7 dsm -1 F0= without compost, F1= compost applied to soil, f2= compost +foliat potassium silicate F3= compost + coated tuber with potassium silicate, f4= compost + foliar potassium humate, f5= compost +coated tuber with potassium humate…”

Phosphorus Fertilizer Effects on Near-Surface Soil Aggregation in Furrow-Irrigated Rice on a Silt-Loam Soil

“…However, two additional factors that can affect aggregate formation, thus aggregate stability, are soil sodium concentration and/or salinity in general. A relatively large sodium concentration can cause clay dispersion and destabilize soil aggregates [9] [10]. Clay particles dispersed by elevated sodium can clog inter-aggregate pores, which, in turn, can reduce surface and sub-surface soil hydraulic conductivity and internal drainage and potentially increase surface runoff and erosion [5].…”

“…Clay particles dispersed by elevated sodium can clog inter-aggregate pores, which, in turn, can reduce surface and sub-surface soil hydraulic conductivity and internal drainage and potentially increase surface runoff and erosion [5]. A widely accepted indicator for potential soil-aggregate dispersion is exchangeable sodium percentage (ESP), where typically an ESP ≥ 15% is considered the threshold for initiating soil dispersion in clayey soils with generally low initial hydraulic conductivity [9]. However, Crescimanno et al [11] reported soil degradation occurred at ESPs as low as 2% to 5% in soils with low CECs.…”