Agriculture Management Impacts on Soil Properties and Hydrological Response in Istria (Croatia)

Abstract

The objective of this work is to study the effects of traditional land uses (vineyard, cropland, and olive orchard) on soil properties, overland flow, and sediment loss in the Istria region (Croatia), by using simulated rainfall. The results showed that soil bulk density (BD) was significantly higher in cropland plots compared to the vineyard and olive orchard. No differences were observed in soil water content (SWC) and mean weight diameter (MWD). Water stable aggregates (WSA), soil organic matter (SOM), and total nitrogen (TN) were significantly higher in the olive orchard compared to the other land uses. In cropland, during the experiment, we did not identify runoff or soil losses. Runoff (Run) and sediment loss (SL) were significantly higher in the olive orchard compared to the other plots. This was very likely a consequence of tillage practices in vertic soils, the use of herbicides, low vegetation cover, as well as the incorporation of hydrophobic organic matter in the soil matrix. The principal component analysis results showed that factor 1 explained the majority of the runoff and erosion variables. Erosion rates and nutrient losses were substantially different between olive orchard plots, and vineyard and cropland. Factor 2 showed that WSA was inversely related to the available phosphorus, water holding capacity, and sediment concentration. Management practices in the studied area should use minimum tilling frequency to have plant cover and avoid erosion.

Tillage-induced impacts on the soil properties, soil water erosion, and loss of nutrients in the vineyard (Central Croatia)

“…Nutrient losses (C loss, P loss, and N loss) follow a similar pattern as soil loss, where the quantity of soil loss is the main driving factor of nutrient losses, indicating the unsustainability of tilled treatment. Similar results were noted elsewhere (Kisic et al, 2002;Bogunovic et al, 2020). Such a significant difference in soil erodibility and losses of nutrients indicate unsustainable management in the study area.…”

“…Rainfall simulations were carried out on the 28 th of November 2018 with UGT Rainmaker Rainfall Simulator (class of pressurized rainfall simulators), 8 per treatment (16 in total) for 30 minutes with rainfall intensity of 58 mm/h as was described in Bogunovic et al (2020).…”

“…Additionally, traffic highly increases BD in vineyards (Ferrero et al, 2007;Bogunovic et al, 2019a) and distorts soil structure (de Lima et al, 2017). Tillage and traffic-induced changes in BD and soil structure modifies soil hydraulic properties (Horton et al, 1994;Dec et al, 2008;Strudley et al 2008) and increase overland flow (Bogunovic et al, 2020). Tillage alters soil physical properties with the breakdown of the current consolidation and structure, which increases air content in the soil and exposes the mentioned aggregates to the air.…”

“…The effect is dependent on the length of the period from conversion to grass-covering, as in shorter period soils are usually more compacted in addition to the tilled treatments, while in longer periods soils compaction was found to be lower as the soils were altered by the penetration and decomposition of the roots (Ni and Ng, 2019). Usually, grass-covering increases SOM (Belmonte et al, 2018;Miller et al, 2019), surface roughness (Biddoccu et al, 2016), and protects the soil from the raindrop impacts (Prosdocimi et al, 2016), reducing the water runoff (WR) (Biddoccu et al, 2017), sediment concentrations (SL) (Keesstra et al, 2016), and soil loss (SL) (Biddoccu et al, 2017;Bogunovic et al, 2020). Original scientific paper DOI: /10.5513/JCEA01/21.3.2810 Telak and Bogunovic: Tillage-induced impacts on the soil properties, soil water erosion, and... accelerate soil erosion; Blouin et al, 2013 reported that the presence of the earthworms may reduce soil erosions rates by up to 50%).…”

“…Study location and experimental design for the determination of soil water content (SWC), water holding capacity (WHC), bulk density (BD), mean weight diameter (MWD) and water-stable aggregates (WSA)(Bogunovic et al, 2020).…”