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UAV-based soil erosion assessment in mediterranean agricultural orchards
Publication . Pagter, Tijs de; Canedo, João Nuno Gomes Vicente; Pijl, Anton; Guerreiro David Coelho, Luísa Isabel; Nunes, João Pedro; Prats, Sergio
Unmanned Aerial Vehicle (UAV) imagery has become an important tool for erosion monitoring, but little is known about its application in Mediterranean agricultural systems such as vineyards and olive groves. In this study, drone flights were conducted in vineyards and olive groves where mulch and biochar treatments had been applied. Digital terrain models (DTMs) and orthomosaics were constructed using a photogrammetry workflow, and model error was determined via global positioning system (GPS) transects. Erosion was assessed using Digital elevation models of Difference (DoD) and compared with fieldbased erosion plot measurements. Explanatory variables for erosion (soil roughness, slope length, steepness, vegetation cover) were derived from DTMs and orthomosaics and were evaluated in a multiple linear regression model. Although direct measurement of erosion from the DoDs was difficult, this was primarily influenced by the unexpectedly low erosion rates during the study period, and the high root mean square error (RMSE) of the DTMs. Significant differences in DTM-derived variables were found between study areas, and especially between areas with organic and integrated management, even though treatments showed similar patterns. The multiple linear regression model demonstrated strong explanatory power, accounting for a large part of the variation in measured erosion using the UAV-derived variables (R 2 = 0.81). Slope and slope length were the most important predictors of erosion together with the interaction between these two variables. The results suggest that soil erosion in the study areas was mostly determined by topographic and management factors, rather than the applied treatments. This study highlights the value of UAV imagery in advancing the understanding of erosion processes in Mediterranean agricultural systems, while also identifying the challenge of accurately measuring erosion from DoDs under conditions of low erosion rates.
Impacts of climate change on the hydrology of a highly disturbed tropical river basin
Publication . Alvarenga, Claudiana Mesquita de; Alvarenga, Lívia Alves; Melo, Pâmela Aparecida; Tomasella, Javier; Pinto, Pâmela Rafanele França; Mello, Carlos Rogério de; Isidoro, Jorge
Climate change significantly affects hydrological responses, yet studies addressing future water availability in the Paraopeba River Basin (PRB), an important tributary of the São Francisco River Basin in Brazil, remain limited, particularly under CMIP6 scenarios and using distributed hydrological modeling approaches. In this context, this study evaluated the hydrological responses of the PRB, under climate change using the MHD-INPE. Future projections were based on an ensemble of seven climate models from the NEX-GDDP-CMIP6 collection, considering a baseline period (1992–2014), three future periods 17(2040–2060, 2061–2080 and 2081–2100) and two socioeconomic scenarios (SSP245 and SSP585). The model satisfactorily reproduced observed streamflow during the baseline period. Under the SSP585 scenario, the projections indicate stronger alterations in water availability, with a potential intensification of flood and drought events, as reflected by reductions in minimum streamflows (Q90) and increases in maximum streamflows (Q10), particularly in sub-basins 4 and 5, where Q90 reductions approach 30% and Q10 increases reach 11.7%. Additionally, a decrease in Q7,10 values was observed, which enabled the analysis of the Conflict Index (Icg), indicating that water withdrawals currently granted may exceed the limits established by existing legislation in future scenarios (Igc > 1).
Adapting mediterranean agroforestry to global change: trade-offs and lessons from the montado
Publication . Fatahi, Nour-Elhouda; Pinto-Correia, Teresa; Ferreira da Silva da Costa Freitas, Maria de Belém; Marques, João Tiago; Belhouchette, Hatem
The Montado, a traditional Mediterranean agro-silvopastoral system, has historically sustained ecological and economic functions through the integration of trees, livestock, and crops. Today, its multifunctionality is increasingly threatened by climate variability, market volatility, and evolving policy frameworks. While previous research has examined Montado dynamics at landscape or plot scales, less attention has been paid to sustainability trajectories at the farm level, where management decisions are made. This study bridges that gap by assessing the sustainability dynamics of farms through a participatory, typology based, scenario approach grounded in a regional typology. We characterized three representative farm archetypes (forestry-focused, mixed agro-silvopastoral, and livestock-focused) and evaluated their trajectories under plausible future scenarios driven by climate, market, and policy pressures. Scenario outcomes were assessed using expert-based scoring (five-point scale), revealing score differences of up to two points across sustainability dimensions between farm archetypes and scenarios. Findings reveal marked trade-offs: Tree-focused farms maintain high environmental value but remain vulnerable to market and labor constraints, while livestock-specialized farms achieve higher economic output at the expense of ecological integrity. Mixed systems demonstrate greater resilience through diversification but face significant labor intensity challenges. We conclude that current “one-size-fits-all” policies generate contradictory incentives. Therefore, adaptive governance frameworks (e.g., results-based payment schemes) are essential to realign farm economics with ecological stewardship. Beyond the Montado, the approach provides insights relevant to other Mediterranean agroforestry systems facing similar sustainability challenges.
Exploring molecular markers associated with Crumbly in Rubus idaeus L.
Publication . de Souza Oliveira, Melissa Yves; Valdiviesso, Teresa; Luz, Francisco Rosado; Duarte, Amilcar; Oliveira, Pedro Brás de; Varela, Ana Rita
The raspberry (Rubus idaeus L.), an economically important crop, is affected by the crumbly fruit disorder, a malformation that leads to fruit disintegration at harvest due to poor drupelet cohesion. Despite previous efforts to identify genetic determinants of this phenotype, its complex inheritance and strong environmental component have limited the development of robust predictive markers. This study assessed the behavior and transferability of previously reported SSR and SNP markers associated with crumbly fruit across plants from a diverse panel of 34 R. idaeus cultivars, including in adjacent genomic regions not screened previously. Phenotyping was based on multi-season fruit performance and drupelet cohesion, and genetic variation was analysed using PCR-based genotyping within a multilocus approach. Consistent clustering patterns were observed across multiple SSR and SNP loci, suggesting a reproducible association between these genomic regions and the crumbly phenotype. Overall, the results support a multilocus genetic architecture underlying crumbly fruit, but also demonstrate that previously reported markers are not universally transferable across genetic backgrounds. These findings highlight the importance of integrated, population-aware marker validation to enable more reliable implementation of marker-assisted strategies in raspberry breeding programs.
Feature papers in BioChem, 2nd Edition
Publication . Aureliano, Manuel; Ma, Buyong
As mentioned in the Editorial of the first edition of the Special Issue on “Feature Papers in BioChem”, biochemistry acts as a key cog in the “clock of the knowledge, permitting that wheels from several science areas move each other” [1]. Moreover, the understanding of life on earth is a perpetual topic in biochemistry, with boundaries dependent on the specificities of each time period and scientific environment [1]. Thus, following the first edition, this Special Issue on “Feature Papers in BioChem, 2nd Edition” still emphases interdisciplinary research in diverse and interconnected scientific areas, with a majority from molecular medicine, cell biology and of course biochemistry (Table 1). Among these scientific fields, a wide range of topics were addressed, as expressed by the diversity of the titles and keywords that can be found in each contribution.