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Article

Positive Effects of Reduced Tillage Practices on Earthworm Population Detected in the Early Transition Period

by
Irena Bertoncelj
*,
Anže Rovanšek
and
Robert Leskovšek
Department of Agricultural Ecology and Natural Resources, Agricultural Institute of Slovenia, Hacquetova ulica 17, SI-1000 Ljubljana, Slovenia
*
Author to whom correspondence should be addressed.
Agriculture 2025, 15(15), 1658; https://doi.org/10.3390/agriculture15151658
Submission received: 22 May 2025 / Revised: 21 July 2025 / Accepted: 28 July 2025 / Published: 1 August 2025
(This article belongs to the Section Agricultural Soils)
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Abstract

Tillage is a major factor influencing soil biological communities, particularly earthworms, which play a key role in soil structure and nutrient cycling. To address soil degradation, less-intensive tillage practices are increasingly being adopted globally and have shown positive effects on earthworm populations when applied consistently over extended periods. However, understanding of the earthworm population dynamics in the period following the implementation of changes in tillage practices remains limited. This three-year field study (2021–2023) investigates earthworm populations during the early transition phase (4–6 years) following the conversion from conventional ploughing to conservation (<8 cm depth, with residue retention) and no-tillage systems in a temperate arable system in central Slovenia. Earthworms were sampled annually in early October from three adjacent fields, each following the same three-year crop rotation (maize—winter cereal + cover crop—soybeans), using a combination of hand-sorting and allyl isothiocyanate (AITC) extraction. Results showed that reduced tillage practices significantly increased both earthworm biomass and abundance compared to conventional ploughing. However, a significant interaction between tillage and year was observed, with a sharp decline in earthworm abundance and mass in 2022, likely driven by a combination of 2022 summer tillage prior to cover crop sowing and extreme drought conditions. Juvenile earthworms were especially affected, with their proportion decreasing from 62% to 34% in ploughed plots and from 63% to 26% in conservation tillage plots. Despite interannual fluctuations, no-till showed the lowest variability in earthworm population. Long-term monitoring is essential to disentangle management and environmental effects and to inform resilient soil management strategies.

1. Introduction

In temperate-climate zones, earthworms are key soil engineers that influence soil structural stability, porosity, and nutrient cycling, thereby affecting agricultural productivity [1,2,3]. They enhance soil aggregation and influence microbial communities by altering soil pH and resource availability, which supports microbial growth and accelerates decomposition processes [4,5]. Earthworms also increase the concentration of available nutrients in their casts, thereby improving nutrient cycling and enhancing soil fertility [6,7].
However, in agricultural landscapes, earthworms are adversely affected by agricultural intensification, which reduces both their species richness and the overall complexity of soil food webs [8,9]. This decline is partly attributed to frequent tillage [10,11], a common farming practice involving the mechanical manipulation of soil for seedbed preparation, weed control, and crop residue management [12,13]. Conventional tillage practices—typically characterized by deep ploughing and extensive soil disturbance—can be particularly harmful to sensitive and long-living organisms such as earthworms, leading to significant reductions in earthworm density and biomass [14,15,16,17].
To alleviate some of these negative impacts, less intensive conservation tillage approaches and no-till practices are increasingly replacing traditional methods [18,19]. Conservation tillage encompasses a set of soil management practices that minimize soil disturbance and maintain crop residue cover on the soil surface, contributing to carbon sequestration, the maintenance of soil biodiversity, and a reduction in fuel and labour costs [20]. The reduced soil disturbance contributes to the preservation of soil structure and moisture retention, resulting in higher earthworm abundance and biomass compared to conventional ploughing [18,21,22]. These positive effects become even more pronounced when such practices are maintained over longer periods [11,14], likely due to the gradual accumulation of soil organic carbon, microbial biomass, and structural integrity [23]. It has been suggested that, in humid climates and poorly drained soils, the benefits of these alternative tilling approaches may take longer to materialize [18,24]. Nevertheless, conservation tillage has been observed to improve soil moisture within two years following the transition to reduced tillage [25].
In addition to management practices, earthworm populations are also affected by environmental factors. As earthworms are poikilothermic organisms, their activity, growth, metabolism, and reproduction all depend on ambient temperature [26,27]. Consequently, their populations are expected to be sensitive to climatic conditions. Few studies have investigated earthworm responses to reduced tillage over consecutive years following the transition, while simultaneously accounting for climatic variability and crop rotation. These studies report contradicting results. For example, a five-year study following the transition to reduced tillage found positive effects of no-tillage after three years, followed by a sudden decline in earthworm populations, which remained unexplained [28]. A five-year study in Lithuania reported no effect of tillage but substantial interannual variability indicating the importance of environmental factors with significant positive effects of spring temperature and negative effects of autumn precipitation [29]. A 16-year study in Hungary also revealed considerable fluctuations in earthworm abundance due to annual variation in precipitation across different tillage systems, with drought conditions amplifying the negative effects of conventional tillage [11]. Although it has been suggested that tillage practices can override earthworms’ environmental tolerance limits [30], these interactions remain insufficiently understood.
This study assessed earthworm biomass, abundance, and the adult-to-juvenile ratio over a three-year period during the early transition phase (4–6 years) from conventional to alternative tillage practices. The assessment was conducted across three tillage scenarios, (1) continued conventional tillage, (2) transition to conservation tillage, and (3) transition to no-tillage, using three adjacent fields under the same crop rotation to estimate changes during this period.

2. Materials and Methods

2.1. Study Site and Management

The field experiment to compare the effects of different tillage systems was conducted at the Infrastructure Center Jablje (46.141291° N, 14.571643° E) in central Slovenia. The site is characterized by medium-depth (approximately 40 cm) Eutric Cambisols developed on limestone sandy gravel alluvial sediments with silty-loam texture (25% clay, 37% silt and 38% sand). The region experiences a moderately continental climate, with an average annual temperature exceeding 20 °C and annual precipitation ranging from 1200 to 1400 mm, distributed fairly evenly throughout the year [31].
The experimental site covers an area of 2.8 ha and follows a three-year crop rotation (maize, followed by winter wheat + cover crop, followed by soybean). The field was divided into three plots, each measuring 490 × 24 m, and each was managed using conventional ploughing up until the start of the experiment in 2018, at which point one field was switched to conservation tillage, another to no-tillage, while the third maintained the conventional approach. In conventional tilling, soil preparation involved mouldboard ploughing to a depth of 22 cm, followed by final seedbed preparation using either a tine cultivator or a rotary harrow. In contrast, conservation tillage included primary tillage with a disc harrow to a depth of 8 cm, followed by seedbed refinement using a tine cultivator. In the no-tillage system, soil surface integrity was maintained and only disturbed during the formation of seeding furrows.
Throughout the sampling period, the crop rotation consisted of maize (2021), winter wheat followed by a cover crop mixture (2022), and soybeans (2023). Three soil management treatments were applied prior to the establishment of each main crop: conventional tillage (deep inversion ploughing), conservation tillage (reduced soil disturbance), and no-tillage. For the spring-sown crops (maize in 2021 and soybean in 2023), conventional and conservation plots were tilled in late March. In contrast, soil preparation for winter wheat sowing in 2022 was conducted in early October 2021. During the 2022 season, an additional tillage operation was performed on the conventionally and conservation-tilled plots in early August 2022, prior to sowing the cover crop mixture.
A linear transect of five equidistant sampling pits (20 cm apart; each 30 × 30 cm) was randomly established and sampled using the same layout within each 490 × 24 m plot (Figure 1). To minimize edge effects and the influence of soil compaction, all pits were placed at least 2 m from plot borders and positioned outside visible wheel tracks or compacted lanes caused by machinery traffic.
Soil properties were assessed at the beginning of the experiment in 2021, yielding a high clay content (25%) and a pH (measured in KCl) of 7.6, which is typical of limestone gravel soils and indicates neutral-to-slightly-alkaline conditions. Phosphorus (P2O5) and potassium (K2O) levels were high, at 31 mg/kg and 36 mg/kg, respectively. The organic matter content was 4.3%, indicating a nutrient-rich soil environment conducive to effective nutrient cycling and good overall soil health.
The use of mineral fertilizers was adjusted according to crop requirements, applying average amounts of 80–100 kg P2O5, 100–130 kg K2O, and 160–180 kg N per hectare. Herbicides were applied once per year for weed control, except in soybean cultivation, where applications were typically carried out twice annually. For winter wheat, fungicides were applied two to three times per year, and insecticides one to two times per year. The fields were not irrigated.

2.2. Earthworm Sampling

Each year, earthworms were collected in early October (13 October 2021, 7 October 2022, and 3 October 2023), using a combination of hand-sorting of the topsoil layer and solution extraction for depths below 20 cm, in accordance with the ISO 23611-1:2018 standard [32]. Following Gutiérrez-López et al. [33], we replaced the standard extraction solution (formalin or mustard) with AITC, which has been shown to be equally effective for earthworm extraction as formalin, while being less toxic to humans and other organisms. At each sampling location, the topsoil layer (0–20 cm) was excavated (creating a 30 × 30 cm pit) and hand-sorted to collect earthworms. To extract individuals from deeper layers, 2 L of a freshly prepared 100 mg/L AITC solution were poured into each pit, followed by a second application after 15 min. For this purpose, a concentrated base solution (5 g/L AITC in 80% ethanol) was prepared in the laboratory within 24 h of sampling and diluted with water on site to achieve the final concentration. Following application, each pit was monitored for 30 min, and emerging earthworms were collected. All specimens were transported alive to the laboratory, where they were washed to remove soil particles, gently dried with paper towels, and subsequently counted and weighed.

2.3. Weather Conditions in Sampling Years

Precipitation and temperature measurements were obtained from a weather station positioned 500 m from the experimental area (Adcon, A753GSM; Adcon Telemetry GmbH, Klosterneuburg, Austria) [34]. Weather and precipitation data was compared to 10-year averages for the 2012–2023 period (Figure 2). Earthworm sampling was conducted over three consecutive years (2021, 2022, and 2023), during which climatic conditions varied considerably. While 2022 was extremely dry and hot, 2023 was marked by excessive rainfall and local flooding (Figure 2). The hot and exceptionally dry summer (June–August) of 2022, with only 31% of the 10-year mean precipitation for these three months, was followed by a wet September, with precipitation (380 mm) amounting to more than twice the 10-year September average. In 2023, temperature patterns returned to near-average levels, but both summer and autumn months experienced significantly above-average precipitation (Figure 2), with local flooding in August. The total summer (June–August) precipitation in 2023 amounted to 190% of the 10-year average for this period.

2.4. Data Analysis

The data analysis focused on determining the effects of two independent variables—tillage and year, as well as their interaction—on earthworm mass, abundance, and proportion of adults. The data from the two depths studied was pooled. According to Q–Q plots, earthworm mass was normally distributed and therefore a linear model with an identity link function was employed. In contrast, count data of earthworm abundance followed a Poisson distribution, requiring the use of a generalized linear model (GLM) and log link. For the proportion of adult earthworms, which followed a binomial distribution, a GLM with a logit link function was applied. To compare models assessing the effects of year, tillage, and their interaction, we used log-likelihood ratio tests (LRT) and the Akaike information criterion corrected for the small sample size (AICc). Models were ranked according to their strength based on backward selection by eliminating parameters that did not significantly improve likelihood.

3. Results

3.1. Depth Distribution of Earthworms

Over the course of the three-year sampling period, a total of 683 earthworms were collected, corresponding to an average density of 168.9 individuals m−2 y−1. The total biomass was 467.3 g, averaging 115.6 g m−2 y−1. The vertical distribution of earthworms remained relatively consistent across years and tillage systems, with nearly 85% (580 individuals) found in the topsoil layer (0–20 cm), and only about 15% (103 individuals), predominantly larger adults, retrieved from the deeper layer (below 20 cm; Figure 3A). As a result, and despite the difference in numbers, the overall mass retrieved from each layer was similar, with 245.0 g and 222.3 g for the topsoil and deeper layer, respectively (Figure 3B). Therefore, earthworm abundance and biomass data for both depths were pooled for all subsequent analyses.

3.2. Effects of Tillage on Earthworm Population

Tillage had a significant effect on earthworm biomass (Table 1A), reaching a maximum of 13.0 g ± 7.7 SD per sample under conservation tillage, followed by no-till with 11.0 g ± 5.0 SD, and conventional tillage with 7.3 g ± 3.9 SD. In contrast, earthworm abundance was maximal under no-till (median = 17 per sample), followed by conservation (median = 15), and conventional tillage (median = 6). Both earthworm mass and abundance also differed significantly between years, with the lowest values recorded in 2022 (Figure 4 and Figure 5; Table 1A).
As indicated by the significant interaction term “Tillage × Year”, the effect of tillage on earthworm abundance and mass was not consistent across years (Figure 5 and Table 1B), exhibiting considerable interannual variability, particularly in the conservation tillage system, where median abundance ranged from 5 in 2022 to 24 in 2023 (Figure 5 and Table 1B). In contrast, the no-tillage system exhibited the lowest variability in earthworm abundance, with values ranging from 16 in 2023 to 20 in 2022 (Figure 5 and Table 1B). In the dry year, 2022, abundance declined by approximately 70% in both conventional and conservation tillage, but increased by 10% in no-till plot compared with 2021. A conceptual diagram modelling the earthworm abundance during the three-year sampling period is given in Figure 6. For earthworm mass, we recorded a 60% decline in both conventional and conservation tillage, but only a 15% decline in no-till plots compared with 2021. In 2023, the earthworm mass remained 30% lower in ploughed plots, recovered similar values in no-till plots, and exceeded the 2021 values by 15% in conservation tillage.
Tillage also had a significant effect on the proportion of juveniles to adults (Table 1C). As with abundance, the significant interaction term indicated that the effect of tillage on age structure varied across years, while the no-tillage system yielded a fairly consistent proportion of juveniles to adults throughout all three years (Figure 7 and Table 1C). In 2022, the proportion of juveniles dropped from 62 to 34% in ploughed plot and from 63 to 26% in conservation tillage plot (Figure 7 and Table 1C).

4. Discussion

Our results indicate that alternative practices, such as conservation tillage and no-tillage, positively influenced earthworm mass and abundance compared to conventional ploughing over a three-year period. Furthermore, these beneficial effects were already evident during the relatively early transition phase, i.e., within just four to six years following the transition to reduced tillage systems. Previous studies of the transition phase have shown contrasting results of reduced tillage, ranging from no discernible effect on the overall earthworm population [29,35] to considerable interannual variability [11,28].
We also detected a strong interaction between tillage system and year, with a marked decline in earthworm populations in the ploughed and conservation tillage plots in 2022, primarily due to a reduction in juvenile individuals. By 2023, earthworm populations had recovered, and in the conservation tillage treatment, both mass and abundance exceeded the levels recorded in 2021. In contrast, populations in the ploughed field remained approximately 30% lower than in 2021. The no-till system exhibited the least variation in earthworm abundance and mass across years.
When interpreting the reduction in earthworm populations observed in 2022, it is important to consider that the crop grown that year was winter wheat, and both the conventional and conservation plots were tilled in early August prior to summer cover crop sowing. Consequently, the time between tillage and earthworm sampling was only two months in 2022, compared to approximately six months in 2021 and 2023. Therefore the 70% decline in earthworm numbers in conventional and conservation systems might have resulted from the summer 2022 tillage and cover crop sowing. Previous studies on the short-term impacts of ploughing have reported an immediate decline in earthworm populations following autumn tillage, with continued reductions for up to 53 days post-disturbance, while populations would typically have recovered by the following spring [35].
However, the summer cover crop sowing in 2022 coincided with an extreme drought, which may have also contributed to the observed reduction in earthworm populations as precipitation amounted to only 31% of the 10-year average. The effects of environmental stressors such as warming and drought on earthworms have been documented. In regions where climate change has already led to higher precipitation, soil moisture, a critical parameter for earthworm survival [36,37], has been increasing, with a positive effect on earthworm communities [27]. In contrast, drought can reduce earthworm mobility and indirectly affect populations by decreasing plant diversity and the availability of high-quality food resources [38]. In an artificial warming experiment, Briones et al. [39] found that earthworm populations were highly sensitive to elevated temperatures, with warmed plots resulting in a 75% reduction in the number of individuals compared to controls, while species richness declined from seven to three. In our study, the drought of 2022 primarily affected juvenile individuals, resulting in a marked shift in the juvenile-to-adult ratio. The high sensitivity of juvenile earthworms to tillage has been previously reported [40]. In our case, the majority of juveniles were found in the topsoil layer, making them particularly vulnerable to both tillage disturbance and drought stress.
The stability of earthworm populations in the no-tillage system during the 2022 drought likely reflects the combined effects of residue-mediated buffering and the absence of mechanical disturbance. Tillage disrupts earthworm burrows and removes protective surface cover, thereby increasing exposure to temperature extremes and water loss [14]. In contrast, permanent surface residues in no-till systems act as a mulch layer, moderating soil temperature fluctuations and reducing water evaporation, which helps maintain higher moisture levels in the upper soil layers, even during extended dry periods [41]. Additionally, no-till practices enhance soil structure and porosity, improving water infiltration and retention capacity—factors shown to support more stable and resilient soil biological communities under climatic stress [42]. These physical and microclimatic benefits likely provided a more favourable habitat for earthworms throughout the drought period, contributing to the minimal year-to-year population fluctuations observed in the no-till system.
Earthworm biomass and abundance in our study were moderately higher than those reported in other tillage trials [43], including studies involving agricultural practices known to favour earthworm development, such as diverse crop rotations [44]. In addition to management practices, this may be attributed to soil and environmental factors that influence the activity and reproductive success of earthworms [45]. The soils at our study site contain a substantial proportion of clay (25%), which typically confers a higher cation exchange capacity than sandy soils [46]. This, in turn, improves nutrient availability for both plants and soil organisms, including earthworms, and a positive relationship between cation exchange capacity and earthworm biomass has previously been reported [47]. Furthermore, elevated organic matter contents, such as that observed at the study site, and the chemical binding of organic substrates to clay particles have been shown to support earthworm populations. In contrast, alkaline soil conditions appeared to have limited influence, as the strongest earthworm responses were observed under more acidic soil pH levels (pH < 5.5) [17].
Although a meta-analysis has indicated that longer periods (>10 years) are needed for reduced tillage to show a positive effect on earthworm populations [14], a recent study from Brazil noted a decline in earthworm populations with increasing duration of no-tillage management [48]. This may be attributed to soil compaction [49] or the accumulation of toxic pesticide residues associated with long-term no-tillage systems (>20 years) [50]. Although significant soil compaction was already present at our study site by the second year after the transition to no-tillage [25], it did not affect either juvenile or adult earthworm populations. Pesticide residues were not assessed in this study; however, the relatively conservative pesticide application history and the absence of glyphosate use suggest a minimal risk of negative impacts on the soil biota [51].
Both tillage and climatic factors have also been shown to influence earthworm community composition. Responses to drought vary among earthworm functional groups due to their differing life strategies [27]. In a meta-analysis, Briones et al. [14] reported that epigeic and large anecic earthworms are the most sensitive to conventional tillage, as these species primarily feed on surface litter. In contrast, endogeic species appear to be less affected by ploughing, and may even benefit from it due to the increased availability of organic matter in the superficial soil layers [52]. A key limitation of our study is that we did not conduct taxonomic identification of the collected earthworms, which prevented us from assessing potential shifts in community composition across tillage treatments. Such information would have been especially valuable for disentangling the relative contributions of tillage and drought to the observed changes in earthworm populations.
Although our study detected an overall positive effect of reduced tillage on earthworm populations, it is not possible to fully disentangle the impacts of the 2022 drought from the effects of the August ploughing prior to cover crop sowing in the same year. Incorporating multiple sampling dates within each year would enhance the study design and help address this limitation. The use of a single annual sampling point has previously been identified as a constraint [52], as earthworm abundances can change rapidly and substantially in response to environmental conditions.
As our study is ongoing, the coming years will provide further insights into the temporal dynamics of earthworm populations under prolonged implementation of reduced tillage practices. Moreover, a longer observation period will help to mitigate the influence of short-term climatic fluctuations, allowing for a clearer assessment of how different tillage systems affect earthworm populations over time.

5. Conclusions

Our three-year study demonstrated that reduced tillage practices positively influenced earthworm biomass and abundance during the early transition phase compared to conventional ploughing. However, strong interannual variability, especially under extreme climatic conditions such as the 2022 drought, underscores the importance of considering both management practices and environmental factors when assessing earthworm responses. A key practical recommendation emerging from our findings is to avoid summer tillage during periods of drought, as it can exacerbate negative impacts on earthworm populations. The no-tillage system consistently supported the most stable earthworm populations across years, highlighting its potential for enhancing soil biological health under variable climatic conditions. The single-time-point sampling and lack of species-level identification restrict deeper insights into the community dynamics. Nevertheless, continued monitoring will improve our ability to distinguish management effects from climatic variability and allow for a more comprehensive evaluation of soil biodiversity responses to tillage practices.

Author Contributions

Conceptualization, I.B., A.R. and R.L.; methodology, I.B. and A.R.; formal analysis, I.B.; writing—original draft, I.B.; writing—review and editing, I.B., A.R. and R.L.; visualization, I.B. and A.R. All authors have read and agreed to the published version of the manuscript.

Funding

This study was co-funded by core financing from the Slovenian Research and Innovation Agency (grant P4-0431); the Slovene Ministry of Agriculture, Forestry, and Food; and the Slovenian Research and Innovation Agency (project CRP V4-2221).

Institutional Review Board Statement

According to Slovene legislation (Law on animal protection), experiments on invertebrates do not require ethical approval. All animals were released at the collection site after examination.

Informed Consent Statement

Not applicable.

Acknowledgments

The authors would like to thank all the colleagues at the Agricultural Institute of Slovenia who helped with the fieldwork. We also thank Klemen Koselj (Biobit) for his valuable advice on statistical analysis.

Conflicts of Interest

The authors declare no conflict of interest.

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Figure 1. Schematic diagram illustrating the three tillage plots and approximate sampling locations.
Figure 1. Schematic diagram illustrating the three tillage plots and approximate sampling locations.
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Figure 2. Mean monthly temperature and precipitation in 2021, 2022, and 2023 at the study site, compared to 10-year averages (2012–2023).
Figure 2. Mean monthly temperature and precipitation in 2021, 2022, and 2023 at the study site, compared to 10-year averages (2012–2023).
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Figure 3. Median and quartiles of (A) earthworm abundance and (B) earthworm mass collected from the 30 × 30 cm sampling pits at two soil depths (0–20 cm and >20 cm) across three consecutive years. Data are pooled across tillage systems.
Figure 3. Median and quartiles of (A) earthworm abundance and (B) earthworm mass collected from the 30 × 30 cm sampling pits at two soil depths (0–20 cm and >20 cm) across three consecutive years. Data are pooled across tillage systems.
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Figure 4. Median and quartiles of earthworm mass across tillage systems and years. Earthworms were collected from 30 × 30 cm sampling pits using hand sorting for the topsoil layer (0–20 cm) and extraction with allyl isothiocyanate solution for depths below 20 cm.
Figure 4. Median and quartiles of earthworm mass across tillage systems and years. Earthworms were collected from 30 × 30 cm sampling pits using hand sorting for the topsoil layer (0–20 cm) and extraction with allyl isothiocyanate solution for depths below 20 cm.
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Figure 5. As in Figure 4, but for earthworm abundance.
Figure 5. As in Figure 4, but for earthworm abundance.
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Figure 6. A conceptual diagram modelling the earthworm abundance during the three-year sampling period.
Figure 6. A conceptual diagram modelling the earthworm abundance during the three-year sampling period.
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Figure 7. As in Figure 4, but showing the abundance of adult and juvenile earthworms.
Figure 7. As in Figure 4, but showing the abundance of adult and juvenile earthworms.
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Table 1. Ranking of models according to their strength in predicting (A) earthworm mass, (B) earthworm abundance and (C) proportion of adults, based on Akaike information criterion corrected for small sample size (AICc) and log-likelihood ratio test statistic (LRT). Independent variables included tillage (T) and year (Y). The × denotes the interaction term. The best model in each case is highlighted in bold.
Table 1. Ranking of models according to their strength in predicting (A) earthworm mass, (B) earthworm abundance and (C) proportion of adults, based on Akaike information criterion corrected for small sample size (AICc) and log-likelihood ratio test statistic (LRT). Independent variables included tillage (T) and year (Y). The × denotes the interaction term. The best model in each case is highlighted in bold.
(A)ModelkAICcΔAICcLRTdfP(>χ2)
Earthworm massTillage; Year; T × Y10282.61.7345.020.001
Tillage; Year;6280.60.0251.420.007
Year4286.55.8129.440.270
Intercept2293.212.5
(B)ModelkAICcΔAICcLRTdfP(>χ2)
Earthworm
abundance		Tillage; Year; T × Y9328.60.051.12<0.001
Tillage; Year;5389.460.851.22<0.001
Year3436.6108.068.84<0.001
Intercept1483.7155.1
(C)ModelkAICcΔAICcLRTdfP(>χ2)
Proportion of adultsTillage; Year; T × Y9200.90.014.320.001
Tillage; Year;5211.710.87.520.023
Year3215.214.318.840.001
Intercept1225.524.6
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Bertoncelj, I.; Rovanšek, A.; Leskovšek, R. Positive Effects of Reduced Tillage Practices on Earthworm Population Detected in the Early Transition Period. Agriculture 2025, 15, 1658. https://doi.org/10.3390/agriculture15151658

AMA Style

Bertoncelj I, Rovanšek A, Leskovšek R. Positive Effects of Reduced Tillage Practices on Earthworm Population Detected in the Early Transition Period. Agriculture. 2025; 15(15):1658. https://doi.org/10.3390/agriculture15151658

Chicago/Turabian Style

Bertoncelj, Irena, Anže Rovanšek, and Robert Leskovšek. 2025. "Positive Effects of Reduced Tillage Practices on Earthworm Population Detected in the Early Transition Period" Agriculture 15, no. 15: 1658. https://doi.org/10.3390/agriculture15151658

APA Style

Bertoncelj, I., Rovanšek, A., & Leskovšek, R. (2025). Positive Effects of Reduced Tillage Practices on Earthworm Population Detected in the Early Transition Period. Agriculture, 15(15), 1658. https://doi.org/10.3390/agriculture15151658

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