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- Contrasting soil seed bank and vegetation dynamics between protected and disturbed arid rangelands in Southern TunisiaAuthor(s): Tlili, Abderrazak; Neffati, Mohamed; Dadi, Kamel; Ouled Belgacem, Azaiez (Frontiers Media, 2026-04-23)Date: 2026-04-23Type: Journal ArticleStatus: Open accessIntroduction: Over recent decades, accelerated degradation of arid rangelands has led to significant losses in ecosystem function, in some cases surpassing irreversible thresholds that hinder restoration. Soil seed banks (SSBs) serve as critical ecological reservoirs influencing vegetation succession and ecosystem resilience after disturbance.Methods: This study investigates the effects of grazing on both above-ground vegetation (AGV) and SSB dynamics. It evaluates the efficacy of long-term protection as a restoration strategy in arid ecosystems. We compared a protected area (a national park) with adjacent continuously grazed rangelands by monitoring above-ground vegetation during the 2022 spring growing season and conducting an emergence test on soil samples collected in summer 2022 at two depths (0–3 cm and 3–6 cm).Results and discussion: Protection substantially increased vegetation cover and improved surface properties, including litter accumulation and the development of biological soil crusts. The protected site supported persistent perennial, medium- to high-palatability species, while grazed areas exhibited higher SSB density and richness dominated by ephemeral, disturbance-tolerant taxa associated with sparse vegetation and highly disturbed soils. Sorensen’s similarity coefficient (SSCI) indicated high similarity between above-ground vegetation inside versus outside protection (0.77), moderate similarity between SSBs (0.62), and a greater decoupling between above- and below-ground components in the protected area (0.43) compared to grazed rangelands (0.57). Despite the similarity in shared species occurring under both management regimes, total vegetation cover, plant density, and species richness increased significantly under protection, highlighting the negative impact of continuous grazing in arid environments. However, when combined with aridity, plant senescence and surface crust formation may create barriers to regeneration and limit the long-term dynamics of both AGV and the SSB under prolonged protection. These findings indicate that both prolonged protection and continuous grazing can diminish regeneration potential and reduce resilience in arid rangelands. Accordingly, controlled grazing regimes that balance disturbance with sufficient recovery periods, coupled with regular monitoring of SSB, are critical for maintaining ecosystem function and resilience. Further research is needed to investigate SSB dynamics under different management practices, particularly at sites where controlled grazing systems are implemented.
- Multi-model genome-wide association analysis of agronomic traits in a Kabuli chickpea MAGIC-subset population (Cicer arietinum L.) across Mediterranean environmentsAuthor(s): Traore, Fatoumata; Akhtar, Sohail; El Allali, Achraf; Gorafi, Yasir Serag Alnor Gorafi; Hejjaoui, Kamal; Hamwieh, Aladdin; Istanbuli, Tawffiq; Boughribil, Said; Amri, Moez (Frontiers Media, 2026-07-20)Date: 2026-07-20Type: Journal ArticleStatus: Open accessChickpea is one of the most consumed legumes due to its high nutritional value and accessibility to low-income populations. However, due to climate change, chickpea cultivation is exposed to various environmental stresses affecting its production and productivity. This study evaluates the agronomic performance of 168 MAGIC subset population across two Mediterranean environments, in Marchouch (Morocco) and Terbol (Lebanon). Genome-wide association studies (GWAS) were conducted to identify potential marker-trait associations (MTAs) using the general linear model (GLM), the mixed linear model (MLM), and the fixed- and random-effect circulant probability unification (FarmCPU), with kinship and principal components used as covariates. The results revealed high genetic variation among the genotypes tested, with significant genotype-by-environment interactions for most traits studied. Genotypes with good agronomic performance (M-1407, M-2038, M-2079, M-242, M-2551, and M-987) were identified under both environments. Early flowering and maturation resulted in a significant increase in grain yield of around 66%. Grain yield varied from 151.85 to 882.7 g m-2 and from 183.59 to 365.76 g m-2 under Marchouch and Terbol conditions, respectively, showing higher genetic variation under Marchouch than under Terbol. Correlation analysis revealed strong, significant correlations among the studied traits. GWAS revealed clear genetic variation across environments, with Marchouch showing stronger and more consistent association signals than Terbol. In total, 72 reliable MTAs were detected for phenological traits, 38 for plant height, 18 for grain yield, and 197 for hundred-seed weight across both sites. A major genomic hotspot on chromosome 4 (11.97–13.63 Mbp) harbored stable and pleiotropic MTAs. Functional annotation of regions surrounding significant SNPs revealed 59 putative candidate genes, highlighting potential biological processes related to growth, signaling, and stress responses that require further validation. These results provide a foundation for further research on marker-assisted selection to improve chickpea productivity and yield stability in stressed environments.
- Spatiotemporal dynamics of evapotranspiration and implications for agricultural water management in the Lake Tana Basin, Ethiopia: a cloud-computing approachAuthor(s): Worku, Amare G.; Abeyou, Abeyou; Guzman, Christian D.; Zemale, Fasikaw A. (Springer (part of Springer Nature) (Springer Open Choice Hybrid Journals), 2026-08-10)Date: 2026-08-10Type: Journal ArticleStatus: Timeless limited accessEvapotranspiration (ET) monitoring is essential for many aspects of regional water resource management. The Surface Energy Balance Algorithm for Land (SEBAL) is used in this work to examine the spatiotemporal fluctuations of actual ET in Ethiopia’s Lake Tana Basin. To estimate ET, SEBAL was used together with the Google Earth Engine (GEE) platform. Key remote sensing variables such as LST, NDVI, and albedo were extracted using custom JavaScript code. The accuracy of SEBAL-based ET was validated using FAO Penman-Monteith estimates from meteorological station data of 2021 and 2022 and further compared with results from previous studies in similar climatic regions. The daily actual evapotranspiration using the SEBAL model in the Lake Tana Basin ranged from 0 to 7.1 mm day⁻¹, with a daily mean value of 4.96 mm day⁻¹. Our results also showed spatial variability in ET over different land covers; it was established that areas covered by trees had a high evapotranspiration rate, followed by shrubland, built-up land, cropland, and grassland, respectively. Similarly, open water bodies had high evaporation rates. The comparison of SEBAL against the FAO Penman-Monteith method resulted in a strong correlation (R2 = 0.83), a root mean square error (RMSE) of 0.22, and a mean absolute error (MAE) of 0.18. The SEBAL model successfully represented seasonal ET fluctuations (3.0–4.3 mm day⁻¹), with associated uncertainty limits of (± 0.39–0.44 mm day⁻¹). Furthermore, the model differentiated ET across various land covers (1.97–4.08 mm day⁻¹) in a very realistic manner. These SEBAL results demonstrate that the model can reliably estimate actual ET in regions with limited or scarce ground-based hydrological data, providing useful information for managing water in the Lake Tana Basin, Ethiopia.
- HOLPA-based multidimensional assessment for context-specific agroecological transitions in semi-arid TunisiaAuthor(s): Toukebri, Wael; Alary, Veronique; Shiri, Zahra; Barbouchi, Mariem; Bahri, Haitham; Atassi, Layal; Abeyou, Abeyou; Idoudi, Zied; Le, Quang Bao; Rudiger, Udo; M'hamed, Hatem Cheikh; Annabi, Mohamed; Frija, Aymen (Frontiers Media, 2026-03-11)Date: 2026-03-11Type: Journal ArticleStatus: Open accessAgroecological transitions offer a viable pathway for transforming agri-food systems toward sustainability, yet fostering durable adoption and meaningful impact requires a deep understanding of local socio-ecological contexts to design targeted, context-sensitive interventions. This study aims to characterize the socio-ecological context, adherence to agroecological principles, and multi-domain performance to identify leverage points for strengthening system resilience. We applied the Holistic Localized Performance Assessment (HOLPA) framework in six rural communities (167 farm households) in the semi-arid Kef–Siliana transect (Tunisia), combining household surveys, soil sampling, contextual diagnostics, scoring of adherences to agroecological principles, and performance indicators (agronomic, environmental, social, and economic). Results reveal pronounced heterogeneity across the studied communities, with distinct degrees of agroecological integration reflecting divergent biophysical conditions, resource endowments, and institutional contexts. Overall, Tunisian rural communities appear to be engaged in an incipient yet uneven agroecological transition. A consistent duality characterizes this process: Social values, including fairness and equity, and some recycling practices are relatively well established, whereas ecological functionality (soil health, ecological synergies), knowledge co-creation, and climate-mitigation practices remain weak. This heterogeneity underscores that agroecological transitions are highly context-specific processes shaped by local assets and governance environments, rather than uniform or linear pathways. Performance patterns highlight the interplay between diversification and resilience: more diversified systems exhibited lower crop losses, while simplified systems (monoculture-dominated systems) suffered greater agronomic and environmental vulnerability. Our application reveals that HOLPA’s current household-level and static design constrains the analysis of temporal dynamics and landscape-scale interactions; capturing the full complexity of transitions will require future iterations to integrate longitudinal and spatial monitoring. Nonetheless, this study demonstrates that HOLPA proves effective in integrating farm household-level diagnostics with system-level performance, offering structured guidance for developing localized roadmaps that highlight context-specific entry points and potential pathways to co-design resilient, equitable, and context-sensitive agri-food systems.
- k-mer-based approaches to unlock genebank genomics for targeted crop improvementAuthor(s): Backhaus, Anna Elisabeth; Quiroz-Chavez, Jesus; Dreisigacker, Susanne; Cavalet-Giorsa, Emile; Uauy, Cristobal; Krattinger, Simon G. (Nature Research (part of Springer Nature) (Fully open access journals), 2026-06-01)Date: 2026-04-21Type: Journal ArticleStatus: Timeless limited accessGenebanks have a vital role in safeguarding plant genetic resources and providing access to valuable genetic diversity that is absent from modern breeding gene pools. Yet, a major challenge for using genebank materials in crop improvement programs lies in selecting manageable subsets of accessions that maximize genetic diversity for traits of interest. The integration of genomic information is creating new opportunities to address this challenge. Recent studies have shown that k-mer-based bioinformatic approaches capture and reveal previously hidden functional diversity that is missing in elite cultivars. Here we present a perspective on how such approaches enable a precise identification of allele and haplotype diversity across large genebank collections that can guide the strategic selection of accessions for crop improvement. Incorporating this untapped genetic diversity from genebanks into crop improvement pipelines is increasingly recognized as a crucial strategy for developing climate-resilient cultivars.