Search Results (967)

Water erosion is a critical degradation process that reduces fertility and agricultural sustainability, especially in semi-arid regions. The Universal Soil Loss Equation (USLE) allows for the quantification of this phenomenon using factors such as rainfall erosivity (R) and topography (length-slope, LS). In this study, both factors were estimated and analyzed in the Cañitas sub-basin, located in the semi-desert area of the state of Zacatecas, Mexico, characterized by irregular precipitation and limited data availability. The objective of this study is to estimate and analyze the R factor and LS factor to evaluate their influence on soil water erosion processes. Records from five meteorological stations (1986–2022) were used, along with the Modified Fournier Index (MFI) and Geographic Information Systems (GIS) tools, generating spatial maps of rainfall erosivity and topography. An average R factor of 81.69 MJ∙mm/ha∙h∙year was estimated, consistent with the values obtained using the MFI. The LS factor shows that the northwestern area of the study zone has the most extensive and steepest slopes (up to 20). This study analyzes the R and LS factors to identify areas vulnerable to water erosion and to understand the influence of climate and topography in a semi-arid region, which can serve as a reference for planning conservation actions and managing watersheds in semi-arid areas with high climatic variability. Full article

Vegetation phenology is a sensitive indicator of climate change in China’s drylands (aridity index, AI < 0.65). However, accurate phenological monitoring remains challenging due to low signal-to-noise ratios, persistent soil background interference, and the scarcity of ground phenological sites. Existing global phenology products also perform poorly in hyper-arid and arid regions. This study developed an optimal phenology detection framework for China’s drylands by systematically evaluating various vegetation indices, noise-reduction techniques, fitting functions, and dynamic thresholds against ground observations, generating a dataset at 500-m resolution spanning 2001–2024. Specifically, we determined vegetation index thresholds to distinguish vegetated from non-vegetated pixels based on 453 field survey sites. Our results indicate that the Normalized Difference Phenology Index (NDPI) coupled with a 10% threshold and polynomial fitting provided the highest accuracy for Start of Season (SOS) (RMSE = 12.02 days). For End of Season (EOS), EVI2 combined with a 70% threshold and self-weighted double-logistic fitting yielded superior performance (RMSE = 19.89 days). Compared to the MODIS global phenology product (MCD12Q2), our dataset demonstrates significantly higher accuracy (higher R and lower RMSE) and broader spatial coverage, particularly in hyper-arid and arid regions. Spatiotemporal analysis reveals that SOS was earlier while EOS was later in more arid areas, potentially reflecting the opportunistic life strategies of ephemeral plants. Notably, a trend of delayed SOS was observed in these regions, which we potentially linked to the shifts in precipitation regimes under global change. This optimized framework and the resulting Chinese dryland phenology dataset provide a robust foundation for assessing ecosystem resilience and carbon cycle dynamics in water-limited environments. Full article

Pectinases are a group of enzymes widely applied in agri-food processes. This study aimed to isolate and characterize pectinase-producing yeasts and yeast-like fungi from soil and humus samples collected in a Moroccan argan forest, a region characterized by arid to semi-arid climatic conditions, with emphasis on screening and evaluating their pectinolytic activity. Among nine isolated strains, four exhibited detectable pectinolytic activity on pectin agar medium. Two promising isolates were molecularly identified by ITS region sequencing as Coniochaeta pulveracea PX765016 and Coniochaeta ligniaria PX765017. Notably, C. pulveracea PX765016 showed the highest pectinolytic potential, with a pectinolytic degradation index of 4.2 on pectin agar. This strain also exhibited maximal pectinase production after 96 h of submerged fermentation in YEPD medium under optimized conditions of pH 4, 30–35 °C, and 0.5% (w/v) pectin. The crude enzyme obtained under these conditions exhibited a specific activity of 559.90 ± 11.62 U/mg. The enzyme was subsequently subjected to sequential purification comprising ammonium sulfate precipitation, dialysis, and gel filtration chromatography on a Sephadex G-100 column, yielding a 2.99-fold purification with a final recovery of 14%. The purified enzyme exhibited optimal activity at pH 6.0 and 40–55 °C, with a reaction time of 20 min. Kinetic analysis of pectin hydrolysis revealed a Michaelis–Menten constant (Km) of 7.33 mg pectin per mL and a maximum reaction velocity (Vmax) of 1666.7 U/mg. To the best of our knowledge, this is the first report of pectinase production by a member of the genus Coniochaeta, and the first characterization of pectinase activity from C. pulveracea. Full article

Post-fire rehabilitation structures are widely used in Mediterranean burned landscapes to reduce runoff and sediment transfer, yet their ecological associations with early vegetation recovery remain insufficiently documented. This observational study assessed vascular plant composition, species richness, vegetation cover, plant density, aboveground biomass, and soil properties across log barriers, wattles, and log dams in the burned landscape of Ancient Olympia, western Greece. The study area belongs to the humid climatic class of the United Nations Environment Programme (UNEP) aridity framework based on the Thornthwaite aridity index, providing a comparatively wetter Mediterranean post-fire context. Paired depositional and eroded microsites in operationally restored post-fire areas were monitored in 2022 and 2023. The sampling design comprised nine plots and 18 microsites (n = 9 plots, 18 microsites). Generalized estimating equations (GEE), change-score models, principal component analysis (PCA) and permutational multivariate analysis of variance (PERMANOVA) were performed to examine associations of monitoring year, microsite condition and rehabilitation structure type with soil and vegetation patterns. A total of 27 vascular plant species belonging to 16 families were recorded. The average vegetation cover increased from 39.17 ± 21.44% in 2022 to 75.11 ± 12.90% in 2023. Model-based marginal estimates with 95% confidence intervals indicated a large positive increase in vegetation cover over this period. Further, rapid early recovery was indicated by large increases in species richness, plant density and biomass. Depositional microsites were associated with stronger recovery signals than eroded ones, characterized by a larger increase in vegetation cover, density, biomass and species richness. Among rehabilitation structures, log dams showed the highest cumulative floristic richness and a broader observed floristic spectrum, although the species-level contingency analysis provided only marginal evidence for structure-associated differences in floristic composition. Changes in selected soil properties including total nitrogen (total N), ammonium nitrogen (NH4-N), nitrate nitrogen (NO3-N), pH, electrical conductivity (EC), and exchangeable calcium (Ca), magnesium (Mg), and potassium (K), were detected between 2022 and 2023; the multivariate soil pattern was driven primarily by mineral nitrogen, pH, and EC. These findings suggest that, under operational post-fire restoration conditions, rehabilitation structures are associated not only with erosion-control functions but also with microsite differentiation that may shape early plant establishment and biodiversity recovery in Mediterranean burned landscapes. Full article

Organic citrus production in semi-arid Mediterranean regions is increasingly challenged by water scarcity, soil degradation, and rising phytosanitary pressure associated with climate change. This study evaluated different sustainable management strategies under commercial organic citrus production conditions in the Andarax Valley (Almería, southeastern Spain). Two complementary field trials were conducted: (i) the assessment of four weed management systems—shallow tillage, mechanical mowing, sown cover crop, and partial manual mowing—and (ii) the comparison of four mass-trapping systems for the control of Ceratitis capitata. Fruit quality parameters, yield performance, and trapping efficacy were evaluated under commercial organic farming conditions. Weed management treatments did not significantly affect internal fruit quality parameters, including juice content, total soluble solids, titratable acidity, and maturity index, which were mainly determined by cultivar-related factors. In contrast, yield showed significant responses to treatment, growing season, and cultivar. The sown cover crop treatment (T3) produced the highest mean yields in both growing seasons, reaching 56.6 and 72.9 kg tree⁻¹ in seasons 1 and 2, respectively. In the mass-trapping trial, the liquid trap baited with hydrolyzed protein (R-9) showed the highest capture efficacy (0.060 flies trap⁻¹ day⁻¹), significantly outperforming the control treatment (0.014 flies trap⁻¹ day⁻¹) and the other evaluated trapping systems. Conversely, dry trap models (A-9 and V-8) recorded significantly lower capture rates (FTD < 0.01), which may be associated with lower retention efficiencies documented in the literature for dry-killing designs. All treatments exhibited high female selectivity (>94%). In addition, a pronounced edge effect was detected, with significantly higher captures concentrated along the orchard perimeter. Overall, the results support the integration of functional cover crops and perimeter mass-trapping strategies as sustainable tools to improve resilience and pest management in Mediterranean organic citrus production systems. Full article

Aridification and hotter droughts are triggering forest die-off events characterized by high mortality rates and declines in forest productivity. The western Mediterranean Basin is a climate change hotspot where many of these die-off events have affected several tree and shrub species in recent decades. Yet, the responses of canopy greenness and cover, radial growth, and gross primary productivity (GPP) to climate in these die-off sites remain poorly understood across species and biomes. Here, we examined 44 sites across Spain, covering humid, dry sub-humid, and semi-arid biomes, and including nine tree and one shrub species. We obtained and correlated monthly climate data, satellite-derived vegetation indices (Normalized Difference Vegetation Index, Enhanced Vegetation Index), tree-ring metrics (basal area increment, ring-width indices), and GPP. We assessed climate trends and relationships between climate, vegetation indices, growth, GPP, and resilience after five extreme drought years in the period 1984–2023. Climate warming impacted all sites, increasing vapor pressure deficit and reducing soil moisture availability, with semi-arid sites warming the most. Vegetation indices and growth showed the largest declines during extreme droughts in dry sub-humid and semi-arid sites. Correlations with climate variables highlighted strong sensitivity to drought stress, particularly regarding growth metrics. During die-off events, GPP significantly declined in the growing season, but no legacy effects were observed afterwards. Vegetation indices and growth partially recovered one year after drought, with resilience peaking for GPP in semi-arid sites. Hotter droughts constrain GPP and growth, especially in dry sub-humid and semi-arid forests. Forests and shrublands experiencing die-off are diagnostic monitors of drought-induced thresholds in ecosystem productivity. Full article

Climate change is intensifying soil salinization, posing a major threat to crop establishment and productivity, particularly in arid and semi-arid regions. Barley (Hordeum vulgare L.), one of the most salt-tolerant cereals, offers valuable genetic resources for improving salinity resilience at early growth stages. This study exploited the genetic diversity of the Nested Association Mapping (NAM) population Halle Exotic Barley-25 (HEB-25) to dissect salinity tolerance during germination and seedling developmental stages. First, the HEB-25 parental lines (25 wild barley genotypes and cv. Barke) were evaluated under salinity treatment to identify contrasting responses. Based on this screening, four HEB families (01, 04, 09, and 22) were selected out of 25 HEB families for detailed phenotypic and genomic analysis. Seeds of the selected HEB families were subjected to 40% seawater salinity stress and control treatments to assess germination percentage and seedling traits, including shoot length, root length, fresh weight (FW), dry weight (DW), DW/FW ratio, root–shoot ratio, and salt tolerance index (STI). Substantial variation was observed among families for all measured traits under salinity stress. STI values enabled clear differentiation among families: Family 01 exhibited the most consistent overall tolerance profile, Family 22 showed the strongest sensitivity in biomass traits, and Family 04 displayed a trait-specific response with sensitivity at the family-mean level but exceptional within-family diversity, harboring some of the highest individual TI values across the population. A genome-wide association study was conducted using 32,995 SNP markers. A total of 27 significant SNPs were identified, corresponding to 20 quantitative trait loci (QTLs). Of these, 12 QTLs were detected under control conditions, 16 under seawater treatment, and 21 based on tolerance indices, indicating both constitutive and stress-responsive genetic effects. Gene annotation within these regions revealed approximately 23 candidate genes associated with abiotic stress tolerance, including genes involved in ion transport, osmotic adjustment, kinases and stress signaling pathways. HEB_22_003, HEB_04_087, and HEB_01_013 represent the most promising genotypes for salinity breeding. These findings highlight the effectiveness of combining precise phenotyping with high-resolution genomic analysis in the HEB-25 population to uncover the genetic architecture of salinity tolerance at early developmental stages. We identified 20 salinity-responsive QTLs, including five major-effect loci on chromosomes 2H, 4H, 5H, and 7H that consistently explained the largest share of phenotypic variation. These loci co-localized with candidate genes linked to ion homeostasis, Ca²⁺-mediated signaling, protein glycosylation, epigenetic regulation, and root system plasticity, revealing key mechanisms underlying early-stage salt adaptation in barley. The strong and contrasting responses of Family 01 and Family 04 provide an excellent genetic framework for functional validation of tolerance alleles. Collectively, these genomic resources establish a robust foundation for QTL pyramiding, marker-assisted breeding, and the development of climate-resilient barley cultivars for saline agroecosystems. Full article

Textile membrane systems are increasingly used in sports halls because of their low structural weight, rapid assembly, and ability to span large areas. Their operational performance, however, is strongly affected by local climate conditions, envelope configuration and the limited thermal inertia of membrane materials. This study presents a comparative EnergyPlus-based assessment of textile membrane sports halls in six representative climate contexts: Helsinki, Berlin, Niš, Barcelona, Dawadmi and Bangkok. A conventional masonry hall was used as the reference case and compared with a single-layer PVC-coated polyester membrane system and double-layer membrane systems with air gaps of 0.4, 0.5 and 0.6 m, including mechanically ventilated air-cavity variants. The assessment combines four performance indicators: annual operational energy demand, carbon emissions, indicative global cost and thermal comfort expressed through Fanger’s Predicted Percentage of Dissatisfied (PPD) index. The results show that the dominant energy demand is climate-dependent, with heating prevailing in cold climates and cooling becoming decisive in hot-arid and hot-humid climates. Double-layer cases usually show lower operational energy demand and lower associated carbon dioxide emissions than the single-layer membrane case. This improvement, however, is not uniform; it depends on the climatic setting and on the width of the air gap. The comfort results lead to a similar but more limited conclusion. Although PPD is reduced in the double-layer configurations, the values remain above conventional comfort acceptance levels in all tested cases. The double-layer membrane should therefore be understood as a measure that reduces thermal dissatisfaction, not as a complete comfort solution. The economic assessment indicates that membrane systems have substantially lower initial capital costs than masonry construction, while their long-term performance depends on operational energy costs, membrane replacement assumptions and the selected analysis horizon. The study provides a climate-specific comparative framework for early-stage envelope selection in textile membrane sports halls, emphasizing that energy demand, carbon emissions, cost and thermal comfort should be considered together rather than as separate outputs. Full article

Drought is a widespread natural hazard in China that can sequentially trigger meteorological, hydrological, agricultural, and socio-economic drought types, yet traditional drought indices typically focus on a single hydrologic component and cannot capture integrated water deficits across multiple compartments. This study aims to systematically characterize the spatiotemporal evolution of comprehensive drought across China’s ten major river basins and to identify and quantify the main natural and anthropogenic factors associated with drought dynamics. We utilized the Gravity Recovery and Climate Experiment (GRACE) Mascon dataset spanning the entire mission period (April 2002–June 2017), which provides a continuous 15-year observation window suitable for detecting decadal-scale trends and inter-annual variability. Given the documented asynchrony between precipitation and terrestrial water storage changes, a zoned index framework was applied: the Combined Climatologic Deviation Index (CCDI) for arid basins and the Drought Severity Index (DSI) for humid basins. The Theil–Sen estimator and Mann–Kendall test, both non-parametric and robust to outliers, were employed for trend detection, and Pearson correlation analysis was used to evaluate statistical associations between drought indices and potential influencing factors. The results reveal a clear “dry gets drier, wet gets wetter” pattern during 2002–2017: severe drought episodes in humid basins (e.g., the Yangtze) were concentrated in 2002–2006, whereas those in arid basins (e.g., the Haihe) occurred mainly in 2013–2017. Groundwater storage anomaly (GWSA) constituted the primary component of total water storage changes in most basins, with the most rapid depletion rate of −45 mm yr⁻¹ in the northern arid basins. Land use/cover change, especially urban expansion, showed a significant statistical association with drought intensification in arid regions, with its standardized contribution being comparable to that of natural factors such as runoff. This study provides a systematic cross-basin assessment and offers scientific insights for differentiated drought mitigation strategies and water resources management. Full article

Siziwang Banner in Inner Mongolia is a typical arid and semi-arid grassland region where ecological environmental quality is highly sensitive to climate variability and land use and land cover change (LULCC). Clarifying the long-term coupling relationship between LULCC and ecological environmental quality is essential for regional ecological protection and sustainable land management. Based on the Google Earth Engine (GEE) platform, this study integrated multi-temporal Landsat imagery and CLCD-based land use datasets, including an updated 2024 land use layer, to construct a Remote Sensing Ecological Index (RSEI) using standardized and direction-corrected principal component analysis. land use transition matrix analysis, spatial autocorrelation analysis, ecological contribution rate calculation, and GeoDetector were further applied to reveal the spatiotemporal evolution patterns, ecological effects, and driving mechanisms of LULCC in Siziwang Banner from 2000 to 2024. The results showed that: (1) grassland was consistently the dominant land use type, accounting for more than 90% of the total area. The overall land use pattern was characterized by stable grassland dominance, decreasing farmland and unused land, and slight increases in grassland and construction land; forestland showed a high relative growth rate but remained very small in absolute area. (2) The regional ecological environmental quality remained at a lower-to-medium level, with mean RSEI values ranging from 0.27 to 0.47. RSEI showed a phased pattern of initial improvement, subsequent decline, and partial recovery; the marked decline around 2015 was associated with the combined effects of drought stress and land use degradation rather than a single driving factor. RSEI exhibited significant positive spatial autocorrelation, with Moran’s I values ranging from 0.898 to 0.993. High-value clusters were mainly distributed in the southern region, whereas low-value clusters were concentrated in the central and northern regions. (3) Different land use transitions produced differentiated ecological effects. The conversion of unused land to grassland contributed positively to ecological restoration, while grassland degradation and construction land expansion exerted negative effects. The positive RSEI response of some grassland-to-farmland transitions should be interpreted cautiously in relation to local irrigation and intensive farmland management. (4) GeoDetector results indicated that land use type and DEM were the dominant factors controlling the spatial differentiation of RSEI, with average q values of 0.7188 and 0.6178, respectively. The interaction between DEM and land use type showed the strongest explanatory power, indicating that ecological quality was jointly shaped by land use structure and natural background conditions. This study provides a scientific basis for grassland protection, unused-land restoration, farmland management, and spatially differentiated ecological restoration in Siziwang Banner and similar ecologically fragile arid and semi-arid grassland regions. Full article

Drought is a major global hazard, yet critical knowledge gaps persist regarding how the El Niño–Southern Oscillation (ENSO) modulates it in topographically complex equatorial regions. This study characterizes ENSO’s spatiotemporal influence on drought across Ecuador’s four principal Köppen–Geiger climate zones: Amazon, Andean highlands, temperate, and arid coastal. Using meteorological data (1985–2015), we computed the Standardized Precipitation Evapotranspiration Index (SPEI) across multiple timescales. Ten ENSO indices were evaluated using Wavelet Coherence analysis to identify non-stationary, scale-dependent correlations and phase dynamics. Results show that tropical, temperate, and Andean (polar tundra) climates exhibit prolonged climatic memory, with significant ENSO correlations across 1- to 24-month SPEI scales. Conversely, arid regions display shorter memory, with correlations dissipating at longer timescales due to limited moisture storage. Phase analysis reveals two high-coherence intervals (1995–2000 and 2007–2013) at the 3-year return period, in which ENSO indices led drought by 9–18 months, underscoring their predictive potential. At 6- and 11-year periods, ENSO signals generally lag SPEI, indicating prolonged drought retention. The Trans-Niño Index and Southern Oscillation Index proved particularly sensitive for the Amazon–Andes transition. These findings establish a robust framework for improving drought monitoring and climate adaptation in vulnerable equatorial regions. Full article

Climate change threatens ecosystem stability in arid Central Asia, yet regional vegetation responses remain poorly resolved at the operational scale of land-use policy. We integrated long-term meteorological records (2000–2024) from Kazhydromet with Landsat surface-reflectance imagery for four epochs (2010, 2015, 2020, 2025) across the five administrative regions of Southern Kazakhstan (≈710,000 km²). After cross-sensor harmonization of Landsat 5 TM and Landsat 8 OLI, dense vegetation cover (NDVI > 0.4) increased modestly across all regions, with the cumulative area growing from 9.09 to 9.60 million hectares (+5.6%) and a transient 2020 minimum linked to the 2018–2020 drought. Per-region OLS trend slopes were not statistically significant at p < 0.05, given the four-epoch sampling (n = 4). A composite Biodiversity–Climate Sensitivity Index (BCSI), constructed from four normalized components (temperature trend, precipitation deficit, NDVI trend, and the coefficient of variation of dense-vegetation cover as a biodiversity–vulnerability proxy), identifies the lower Syr Darya floodplain and former Aral Sea margins as the most sensitive territories and the Northern Tien Shan as the most resilient. The framework provides an operational evidence base for climate-adaptive conservation aligned with SDG 13 and SDG 15. Full article

Over the past decade, state-led waterfront projects in the Gulf region have emerged as an intriguing urban phenomenon, repositioning World Heritage Sites (WHSs) located along coastal zones within large-scale urban development. In a region increasingly exposed to urban transformation and a hot-arid climate, these waterfront transformations also intersect with the emerging need for climate-adaptive urban resilience. While such projects are often framed as a means of contemporary extension of heritage assets, their implications for WHSs remain underexamined. This study investigates how state-led waterfront developments in the peripheries of the World Heritage Sites function as socio-spatial mediators that reconnect maritime heritage with these sites while enhancing or undermining urban resilience and climate adaptability. Drawing on comparative case studies from the Historic Jeddah (inscribed in 2014) and the Pearling Testimony of an Island Economy, Muharraq, Bahrain (inscribed in 2012), the data collection comprises literature synthesis, policy and planning documents, state-led waterfront proposals, and site observations, analyzed through the Comprehensive Waterfront Development Index (CWDI) framework. The analysis expands the existing six dimensions of the CWDI framework to eight dimensions and dissects two of the dimensions to a further two more. This expansion and dissection contextualize waterfront developments as socio-spatial mediators re-connecting maritime heritage with the WHSs. Findings reveal that while both cases integrate CWDI dimensions, social integration is limited, whereas climate adaptation remains absent, diminishing the urban resilience of the WHS. By doing so, this study contributes to broader debates on sustainable development and climate-adaptive urban resilience in rapidly transforming peripheries of WHSs. Full article

The accurate characterization of global precipitation regimes, encompassing not only the mean quantities but also the seasonal structure, concentration, and spatial heterogeneity, is essential for understanding the hydroclimatological dynamics and supporting climate-sensitive applications. This study presents a multi-scale precipitation climatology based on the IMERG Final Run V06B dataset (2001–2021) integrating satellite-derived monthly precipitation fields, unsupervised K-means clustering, Walsh–Lawler concentration metrics, and pixel-scale regime-dynamics indicators. The analysis identifies eight physically interpretable global precipitation regimes and six Italian sub-regional regimes characterized by distinct seasonal structures and precipitation persistence patterns. The resulting classifications exhibit a strong consistency with major atmospheric circulation domains, including monsoonal, mediterranean, continental, and equatorial precipitation regimes. A Hovmöller diagram highlights the seasonal northward migration of the Intertropical Convergence Zone (ITCZ) from approximately 5° S in January to 10° N in August. The K-means classification identifies eight physically interpretable global regimes, including a perhumid equatorial regime, a South-Asian monsoonal regime, a Southern-Hemisphere Mediterranean type, and a transitional autumn-peaked Mediterranean–Atlantic regime covering most of Italy and the broader Mediterranean basin. At the Italian scale, a dedicated K = 6 clustering reveals six distinct precipitation regimes, characterized by contrasting seasonal structures: the Alpine Convective regime, unique to the Alps and pre-Alpine foothills; the Po Valley Padano regime, the least seasonal regime in Italy; the Apennine Hybrid; the Tyrrhenian Mediterranean; the Adriatic Transition; and the Semi-arid Mediterranean regime, dominant across Sicily, Sardinia, and coastal southern Italy. The Walsh–Lawler Concentration Index increases markedly from north to south (~0.58), indicating a pronounced intensification of the temporal concentration of precipitation toward the Mediterranean climatic extreme. Overall, the study demonstrates the capability of high-resolution satellite climatologies to identify dynamically coherent precipitation-regime structures across multiple spatial scales and provides a quantitative baseline for future applications in hydrology, climate-risk assessment, and climate-change impact analysis. Full article

El Niño–Southern Oscillation (ENSO) has been identified as a key factor influencing grapevine phenology and harvest timing in South America. Nevertheless, few long-term analyses have explored its varietal impacts in hyper-arid viticultural regions. The goal was to evaluate the effect of ENSO phases on harvest dates and bioclimatic indices in different grapevine varieties cultivated in Northern Chile. The results revealed that Muscat of Alexandria showed little variation in harvest timing across ENSO phases. In contrast, harvest time in Thompson Seedless was delayed under La Niña events, being strongly correlated with the Maximum Spring Temperature Summation (SON_max) Index. Moscatel Rosada and Flame Seedless showed non-statistical significance and high variability on harvest dates. El Niño phases were consistently warmer than La Niña events that showed markedly greater interannual variability on harvest dates and bioclimatic index values. The strength of correlations was improved when the bioclimatic indices were recalculated over adjusted seasonal windows, underscoring the need for phenology-based rather than calendar-based approaches. These results provide new evidence of the heterogeneous responses of table and Pisco grapevine varieties to ENSO events in the hyper-arid regions of Northern Chile, underscoring the varietal differences in sensitivity to early-season climatic anomalies. Full article