A hedgerow is a linear strip of woody vegetation that, when strategically positioned, can act as a vegetative barrier. It reduces surface runoff velocity and promotes sediment deposition. Hedgerows and vegetative barriers are also landscape elements that provide several ecosystems services, like biodiversity enhancement. However, in semiarid regions, limited water availability might reduce their positive effects to an extend that still not fully understood.
We hypothesize that vegetative barriers also influence soil moisture profiles and sedimentation dynamics along their width. To test this hypothesis, we monitored soil moisture and sediment deposition over two years in a 30 m length, with a width ranging from 4 to 7 m, vegetative barrier downslope of an olive orchard in southern Spain. The basin of the hedgerow’s stretch is 0.13 ha with an average slope of 17.1%. Soil moisture was recorded using 16 continuous sensors and point measurements with a neutron probe (12 accesses to the neutron probe) for calibration. Soil moisture was measured at three zones along the hedgerow (upper, intermediate, and lower) and at four soil depths (0-15, 15-30, 30-60, and 60-90 cm), with the moisture sensor reading in the intermediate depth of each depth range. Sediment deposition was assessed using 26 erosion pins in the intermediate (12) and lower (12) sections. Rainfall data was registered using an autonomous rain gauge with a 10-minute resolution inside the experimental area. Erosion in the upslope area in the olive orchard was calculated using RUSLE. These data allowed comparison between erosion pin measurements inside the vegetative barrier and erosion estimates in the vegetative barrier catchment.
Our results revealed significant statistical differences in soil moisture and sediment dynamics. Soil moisture was higher in the intermediate and lower sections. Also, evolution of soil moisture in the top (0-15 cm) layer presented the highest temporal variability, while the other layers had a lower temporal variability. soil profiles showed distinct patterns across depths. In the intermediate and lower zone, the other layers had an average higher moisture during the years, which did not differ significantly among themselves. On the other hand, in the upper zone, the 15-30 cm layer had the highest average soil moisture content. Sediment deposition was greater in the intermediate zone, with a net accumulation in an erosion pin of 2.38 cm compared to 0.25 cm in the lower section. This resulted in a sediment trapping efficiency estimation in the vegetative barrier of 4%, lower than reported in previous studies. These findings suggest that hedgerows, far from competing with crops, can serve as valuable allies in soil conservation and water management- when they are properly located and managed.
Aknowledgment: Work was funded by Spanish Ministry of Science and Innovation (PID2019-105793RB-I00), project SCALE and TUdi (EUHorizon2020 GA 862695 and 101000224), and a predoctoral fellowship (PRE2020-093846). It also received funds by project RELAND (PID2023-146177OB-C21 and PID2023-146177OB-C22) by MICIU/AEI/10.13039/501100011033 and by FEDER, UE.
How to cite: Muñoz, J. A., Guzmán, G., Soriano, M. A., and Gómez, J. A.: Impact of a vegetative barrier on soil moisture and sediment deposition in a Semi-arid olive crop, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-601, https://doi.org/10.5194/egusphere-egu26-601, 2026.
The NDVI and PRI vegetation indices (VIs) are widely used to assess grassland condition; however, our understanding of their sensitivity to soil chemical properties and moisture content needs to be expanded. Linking soil chemical properties and water availability to spectral responses increases the reliability of grassland monitoring and management. The present study aimed to analyze two distinct grassland ecosystems, where the spatial heterogeneity of soil chemical parameters and their effects on vegetation indices were investigated.
The study was conducted in 2025 at two research sites, one in the Serbian Rekovac region (RS) and one in the Hungarian Balaton Uplands (HU). Both research sites covered approximately 1 ha. At each site, we collected 32 and 35 soil samples and measured soil chemical parameters (pH, soil organic carbon (SOC), total nitrogen, potassium, and phosphorus) in a laboratory. In the field, we also used non-destructive measurements, including soil elemental compositions using XRF (e.g., Fe, Ca, Cu, As, Pb), soil water content (SWC; Hydrosense II, Campbell Scientific), and vegetation NDVI and PRI values using spectral reflectance sensors (Meter Group) approximately 2 meters above ground. Soil CO2 emissions were measured using an EGM5 IR analyzer (PP Systems). Data for each sampling point were averaged prior to analysis.
When we compared the two grassland sites, we found significantly higher C to N ratio, total N, K, P, SOC, CaCO3 concentration, and CO2 emissions at the HU site, while vegetation NDVI and PRI values were significantly lower (p < 0.05). However, SWC and soil temperature data showed no significant differences (p > 0.05). Given the large number of measured soil chemical parameters, cluster analysis and principal component analysis (PCA) were applied to reduce dimensionality and identify the main factors influencing vegetation indices. Cluster analysis grouped the variables into three distinct clusters, with the Serbian site in one and the Hungarian sites in two. We found that NDVI and PRI values were strongly and negatively correlated with many of the soil chemical parameters (e.g., pH: r = -0.94 and -0.89, SOC: r = -0.86 and -0.83, respectively). Soil CO2 emissions showed only moderate correlations with specific parameters, such as pH, potassium, or C to N ratio (r = 0.50-0.53). SWC, on the other hand, did not show any clear correlations with the main parameters measured.
Our results indicate that variability in vegetation indices was primarily associated with soil chemical gradients rather than soil moisture conditions. Our study showed that local heterogeneity can strongly affect soil chemical data, which in turn affects VIs. Both sites were assessed twice, but further measurements are planned to provide more robust support for our findings.
Acknowledgments: The research was funded by the Sustainable Development and Technologies National Programme of the Hungarian Academy of Sciences (FFT NP FTA) and the 2023-1.2.4-TÉT-2023-0009 project.
How to cite: Horel, Á., Bódi, A., Mészáros, J., Djordjevic, D., Sakan, S., and Zsigmond, T.: Relationships between soil chemistry, soil moisture, and vegetation indices in grassland ecosystems, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-9766, https://doi.org/10.5194/egusphere-egu26-9766, 2026.
Monitoring the nutrient status of grapevines is important for optimizing fertilization strategies, ensuring grape quality, and minimizing environmental impacts in precision viticulture. The traditional laboratory leaf analysis for nutrient monitoring is time-consuming and costly, so rapid, non-destructive, on-site measuring techniques are needed. The aim of present study was to investigate the seasonal variability of grapevine nutrient status using hand-held spectral sensors, specifically focusing on key phenological stages. The study was carried out in a vineyard located in the Balaton Uplands region (Hungary), which serves as a long-term monitoring site for various environmental and viticultural research projects.
Measurements were conducted at four distinct phenological stages (flowering and fruit set, bunch closure, veraison, harvest), with 40 leaf samples collected per occasion. The physical and physiological characteristics of the leaves were recorded, including fresh and dry weight, leaf area, leaf mass area (LMA), chlorophyll content (CCI), and Normalized Difference Vegetation Index (NDVI). In addition, particular emphasis was placed on the Normalized Difference Greenness Index (NDGI), to examine the correlation with the nitrogen content (N) of the leaves. CCI was measured using an MC-100 (Apogee Instruments), while NDVI and NDGI were collected using PlantPen NDVI 310 and N-Pen N 110 handheld instruments (Photon Systems Instruments). Leaf parameters were determined in a laboratory. This multi-temporal approach allowed us to evaluate the sensitivity of these spectral indices in tracking nutrient fluctuations throughout the growing season.
In general, the highest average NDVI (0.771) was measured at the flowering and fruit set stage, while the highest values of the other indicators were usually recorded during the veraison and harvest periods. The highest LMA-adjusted NDGI values were recorded at veraison, suggesting a peak in leaf N concentration. Ongoing laboratory analyses are expected to confirm these results. Significant differences were found in LMA-adjusted NDGI values between veraison and other phenological stages. A strong positive correlation was between NDGI and CCI (r=0.60, p<0.05) for the whole season. This connection became even stronger in the later stages, reaching r=0.68 at bunch closure and r=0.89 at veraison (p<0.05). Principal Component Analysis (PCA) showed no clear separation between the phenological stages based on the investigated parameters.
Acknowledgments: Tibor Zsigmond is grateful for internal funding by HUN-REN ATK (Project number 0405B1481P). The research was funded by the Sustainable Development and Technologies National Programme of the Hungarian Academy of Sciences (FFT NP FTA) and the 2023-1.2.4-TÉT-2023-0009 project.
How to cite: Zsigmond, T., Bódi, A., and Horel, Á.: Hand-held spectral sensors for in-field grapevine nutrient monitoring, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-9846, https://doi.org/10.5194/egusphere-egu26-9846, 2026.
This study assesses the impact of pine tree plantations on soil water content in Zapatoca, northeastern Colombia, using multitemporal electrical resistivity tomography (ERT) combined with laboratory analyses. The research compares four land covers: a native tree forest and three pine species in plantation: Pinus maximinoi, Pinus oocarpa and Pinus patula, each of which has distinct physical and chemical soil characteristics. Soil profiles were characterized in terms of texture, bulk density and chemical properties. ERT data were collected at three different times and analysed using Archie's law and generalised Archie's law to estimate volumetric water content. These estimates were validated against direct measurements from soil samples. The results indicate that the native forest retains a higher water content at greater depths, which is associated with a high clay content, a lower canopy density and an absence of surface barriers. In contrast, pine plantations showed shallower moisture retention, potentially due to high evapotranspiration rates, dense canopy cover and physical barriers such as thick layers of pine needles. Multitemporal ERT data effectively captured seasonal changes in subsurface moisture and correlated well with direct measurements; however, estimations were less accurate in silty soils. The findings suggest that pine plantations may reduce water infiltration and recharge, influenced by soil texture, forest management, and canopy structure. These insights highlight the usefulness of ERT in evaluating the hydrological impact of changes in land use and support the development of informed afforestation and conservation strategies.
How to cite: Herrera, K., Bernal-Olaya, R., and Colegial-Gutierrez, J.: Defining the impact of pine cultivation on soil water content in Zapatoca, Santander, using Electrical Resistivity Tomography (ERT)., EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-15553, https://doi.org/10.5194/egusphere-egu26-15553, 2026.
In this study, we examined and compared the characteristics and processes directly influencing soil carbon content and carbon turnover in a slightly sodified, haevy textured soil in a near-natural sodic grassland and a 100-year-old oak afforestation established in its immediate vicinity, originally with identical soil conditions. We compared the amount of carbon stored at the two sites in the above ground living phytomass, in the organic matter accumulated in the litter layer (dead wood, litter), and in the living root biomass in the upper 10 cm layer of the soil. In the soil samples, we analyzed the soil organic carbon content, the microbial biomass, the dehydrogenase and sacharase activities by sampling in 10 cm thick layers between 0-40 cm, replicated per season. We measured the CO2 emission of the soil surface replicated per season.
In the 100th year after afforestation, soil pH and base saturation were lower in the forest area. Carbon stock was higher in the near-natural grassland area (0-40 cm: 1144±35 g∙m2) than in the planted forest (973±34 g∙m2). At the same time, the C content of the living phytomass increased to 14,712 g∙m2 in the forest area, compared to 298±65 g∙m2 measured in the grassland. The amount of C stored in the litter in the afforested area was 4 482±1 018 g∙m2, and in the grassland 162±61 g∙m2. The C content stored in the root system was higher in the grassland, 1676±988 g∙m2, compared to 94±57 g∙m2 in the forest. Microbial biomass and enzyme activity were higher in the grassland in all seasons and in all layers, and CO2 emissions were also higher in the grassland (0.235 g∙m2∙h-1) compared to the forest (0.337 g∙m2∙h-1).
According to our studies, the rearrangement of surface and subsurface carbon storage processes changes significantly over 100 years and affects the chemical and biological processes of the soil as well.
How to cite: Novák, T. J., Krusóczki, A., Béni, Á., Juhász, E., B. Kovács, A., Ábri, T., Keserű, Z., Kovács, G., Tuba, G., and Zsembeli, J.: Characterization and comparison of soil and vegetation carbon stocks in natural grassland and afforestation, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-16929, https://doi.org/10.5194/egusphere-egu26-16929, 2026.
Nature restoration projects often aim to improve biodiversity, while many soil-related ecosystem services like water retention, are often not accounted for and may negatively be affected by restoration measures. In the Netherlands, topsoil removal, or sod cutting, is commonly implemented in areas where agricultural fields are being transformed into heathlands to remove the nutrient-enriched topsoil. Heathland restoration is a key objective within the European Natura 2000 network. While this intervention effectively lowers soil fertility and promotes the establishment of the target heathland vegetation thereby fostering biodiversity, its long-term effects on soil hydraulic properties are not well understood. Given that soil water retention is a key soil property influencing catchment resilience to droughts and floods, assessing soil hydraulic change following restoration is necessary for evaluating restoration outcomes.
This research investigates the change of soil water retention in restored heathlands within the Drents-Friese Wold national park, the Netherlands, located within the European Sand Belt. At each site, 30 to 50 cm of organic-rich topsoil was excavated, exposing underlying horizons with minimal pedogenic development. A chronosequence approach was applied at sites where topsoil removal occurred in approximately 1995, 2005, and 2020, representing up to three decades of soil development. Undisturbed soil samples were collected from each chronosequence stage; from an abandoned intact agricultural site, and from long-established heathland exceeding 200 years that represents the restoration target. Additionally, samples were collected from the subsoil at 40 cm depth beneath intact agricultural soil to separate the effects of topsoil removal from the original soil conditions at that depth. Soil water retention curves were determined for all samples using combined suction table and pressure plates, complemented by measurements of bulk density, organic matter content, and particle size distribution.
Although topsoil removed sites achieve nutrient-poor conditions favorable to heathland species, visual soil observations suggest that the aggregated structure and biological pore networks present in the original agricultural topsoil did not recover even after three decades. By quantifying recovery timescales and comparing hydraulic properties across restoration states, this research illustrates that rapid measures for nature restoration comprise long-term soil functioning, with implications for restoration practice across similar ecosystems.
How to cite: Farzanegan, E., Candel, J. H. J., and Vanacker, V.: Long-term soil hydraulic recovery following topsoil removal in restored nature, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-19421, https://doi.org/10.5194/egusphere-egu26-19421, 2026.
