Search Results (5,962)

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

Purple basil (Ocimum basilicum L.) is a medicinal plant widely recognized for its richness in bioactive compounds; however, its production in semi-arid regions is often constrained by soil and/or irrigation water salinity. Micronutrient fertilization may contribute to plant stress alleviation under salinity, since elements such as Mn, Mo, and Zn are involved in essential processes related to photosynthetic metabolism and physiological adjustment. This study aimed to evaluate the short-term effects of Mn, Mo, Zn, and their combinations on growth, gas exchange, and relative chlorophyll indices of purple basil plants subjected to severe NaCl stress under greenhouse conditions. The experiment was conducted under greenhouse conditions for 30 days in a randomized block design with nine treatments and four replicates: a non-saline control without micronutrients, a saline control without micronutrients, and plants exposed to 100 mM NaCl with substrate application of Mn, Mo, Zn, MoMn, ZnMo, ZnMn, or ZnMoMn. Micronutrient sources were applied to the substrate at 3.5 g kg⁻¹ according to each treatment. Fertilization with Mn, Mo, Zn, and their combinations enhanced plant stress alleviation under salinity compared with the saline control without micronutrients, with positive responses in growth and physiological performance, including increases in chlorophyll indices. The double combinations MoMn, ZnMo, and ZnMn attenuated the effects of NaCl, especially by increasing leaf area. Mn stood out for increasing net photosynthesis and water-use efficiency, whereas Mo and ZnMo were associated with higher relative chlorophyll indices. Although the triple combination ZnMoMn improved some traits compared with the saline control, its lower efficacy relative to selected single or double applications may indicate that the simultaneous supply of the three elements reduced specific synergistic effects, possibly due to nutritional imbalance or antagonistic interactions among micronutrients under severe salinity. Overall, micronutrient fertilization, particularly through specific double combinations, may contribute to short-term mitigation of NaCl-induced stress responses under controlled greenhouse conditions. Full article

Groundwater flow is an integral part of the Earth’s water cycle and plays a key role in assessing groundwater resource potential, characterizing the upper limit of possible groundwater withdrawal over a long period without depletion. The objective of this study is a comprehensive regional assessment of groundwater flow and the natural and predicted resources of fresh and low-mineralized groundwater in Southern and Western Kazakhstan. This assessment is based on an analysis of hydrogeological conditions and water balance, taking into account climate variability and anthropogenic load, to justify sustainable water resources management in arid territories. This article provides a regional assessment and mapping of groundwater flow, taking into account climate and anthropogenic changes in Kazakhstan, to refine the predicted resources of fresh and low-mineralized groundwater. The basin balance calculation results indicate that in arid and semi-arid regions, the decline in groundwater recharge by the 2050s will generally not exceed 10%. The average layer of groundwater flow of renewable groundwater resources in the Kazakhstan part of the Zhaiyk-Caspian water management basin (WMB) is estimated at 33.4 mm/year, and the average modulus of groundwater flow is 1.06 L/s per 1 km². The average layer of groundwater flow of renewable groundwater resources in the Kazakhstan part of the Aral-Surdarya water management basin (WMB) is estimated at 14.8 mm/year, and the average modulus of groundwater flow is 0.47 L/s per 1 km². The average layer of groundwater flow of renewable groundwater resources in the Kazakhstan part of the Shu-Talas water management basin (WMB) is estimated at 26.5 mm/year, and the average modulus of groundwater flow is 0.84 L/s per 1 km². For mountainous and folded regions, the average layer of groundwater flow of renewable groundwater resources in the Balkhash-Alakol water management basin (WMB) system is estimated at 70.7 mm/year, and the average modulus of groundwater flow is 2.24 L/s per 1 km². For intermontane and foothill basins, the average layer of groundwater flow of renewable groundwater resources in the Balkhash-Alakol water management basin (WMB) is estimated at 54.3 mm/year, and the average modulus of groundwater flow is 1.72 L/s per km². Full article

High-resolution surface soil moisture (SM) is needed for local hydrological and agricultural applications, but reliable retrieval at 100 m remains challenging. Within this broader methodological context, radiometer-constrained SAR change detection remains a practical and interpretable option for high-resolution soil moisture retrieval. It uses SAR-derived temporal changes to describe fine-scale wetting and drying processes, while passive microwave observations provide volumetric moisture references. This study proposes an improved SMAP-anchored Sentinel-1 change-detection framework (ISSF) for 100 m SM mapping. ISSF addresses these limitations by fitting NDVI-binned upper-envelope samples with a nonlinear quadratic function to normalize the vegetation-dependent backscatter-change range and by using multi-year SMAP dry/wet quantiles to scale the normalized relative wetness into volumetric SM. ISSF was evaluated using in situ measurements, a near-concurrent airborne reference, SMAP-based products, and direct transfer to OzNet. In the Shandian River Basin, ISSF achieved R = 0.549 and ubRMSE = 0.062 m³ m⁻³ at the point scale. Relative to three benchmark change-detection methods, ISSF increased R by 11–53% and reduced ubRMSE by 7–15%. For the airborne-referenced event, ISSF showed R = 0.635 and ubRMSE = 0.027 m³ m⁻³. Under direct transfer to OzNet, ISSF achieved mean R = 0.55 and mean ubRMSE = 0.05 m³ m⁻³. These results indicate that ISSF provides a practical and interpretable approach for 100 m soil moisture mapping in semi-arid regions with sparse to moderate vegetation. Full article

Soil quality assessment, which considers numerous physical, chemical, and biological indicators, has long been a challenge for monitoring soil functions and ensuring sustainable resource use in agriculture. In this study, different indicator selection and weighting methods were compared to derive a reliable Soil Quality Index (SQI) in semi-arid agroecosystems. A total of 117 topsoil samples were taken from the Ap horizon within a 14,200 ha area of the Honam sub-catchment, southwestern Iran. Twenty-one soil indicators were measured and analyzed to assess the overall SQI. Soil indicator selection was performed using Principal Component Analysis (PCA), considering standard and norm value strategies, as well as component rotation. Four weighting approaches, including PCA, Coefficient of Variation (CV), correlation score (r), and Expert Opinion (EO), were applied to the Minimum Dataset (MDS) and Total Dataset (TDS) to compute the Integrated Quality Index (IQI), Nemoro (NQI), simple additive (IQIa), and Fuzzy Fertility Index (FFI). The performance of the SQI models was evaluated using the Sensitivity Index (SI) and their relationships with crop yield. The results showed that the combination of the norm value approach without component rotation was more effective in selecting the influential indicators for SQI determination. The Soil Stability Index (SSI), which integrates soil organic carbon and textural properties, was the key indicator with the highest contribution, ranging between 6.3% and 37.5% in most of the models. Among the evaluated approaches, the IQI-CV-MDS showed the highest sensitivity (SI = 6.8) and the strongest correlation (r = 0.53) with rainfed barley yield. The majority of the samples exhibited moderate SQI values, indicating a general risk of soil quality decline in the study area. The findings of this study highlight that appropriate indicator selection and weighting strategies are essential for improving the reliability of SQI assessments in semi-arid environments with diverse mountainous topography. Full article

Saline irrigation is increasingly practiced in semi-arid regions to cope with freshwater scarcity; however, it strongly affects crop growth, water use, and soil salinity. This study aims to calibrate and validate the AquaCrop model to simulate key growth parameters of winter wheat (cv. Achtar) under saline irrigation conditions in the Tadla Plain, Morocco, focusing on canopy cover (CC), actual evapotranspiration (ETa), soil water content (SWC), biomass (B), and grain yield (GY). The model was first calibrated using observed data from the 2023 growing season and subsequently validated using data from the 2022 growing season. Overall, AquaCrop effectively reproduced crop growth during both calibration and validation phases. During calibration, canopy cover was accurately simulated, with average RMSE values below 1%, while biomass and grain yield were also well reproduced, with low RMSE values (0.25 t ha⁻¹ for B and 0.10 t ha⁻¹ for GY), confirming the robustness of the calibrated parameters. The model also performed well in simulating ETa and SWC, capturing the seasonal dynamics of crop water use and soil moisture. During validation, ETa was satisfactorily reproduced, with an RMSE of approximately 0.80 mm day⁻¹, while SWC showed good agreement with observations, with NRMSE values ranging from 7.9 to 10.5%. Grain yield and biomass were reliably predicted, with NRMSE values below 4%. These results demonstrate that AquaCrop is a reliable tool for simulating winter wheat under saline irrigation and for assessing crop response under salt-affected conditions, providing an integrated evaluation of crop performance, water use, and soil salinity dynamics to support improved irrigation management and water-use efficiency under semi-arid conditions. Full article

Water channel experiments were conducted to investigate the influence of aspect ratio (H/D = 0.9–1.9) on the flow-induced motion (FIM) and hydrokinetic energy conversion performance of an elastically mounted circular cylinder with T-shaped attachments (Cir-T-Att). The results indicate that the aspect ratio critically governs the vortex-induced vibration (VIV) to galloping transition by modulating the effective angle of attack. While larger H/D promotes galloping and higher amplitudes under low damping, this benefit is negated under elevated system damping, where amplitudes are uniformly suppressed. Consequently, the maximum power output exhibits a non-monotonic dependence with H/D. Within the investigated parametric range, peak performance occurs at H/D = 1.1, with a total damping ratio ζ_total = 0.122 and reduced velocity U_r = 11.25. For practical harvester design, the optimal H/D should be selected by aligning the intended oscillation regime with local flow characteristics. 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

This study aimed to determine the prevalence and risk factors associated with Toxoplasma gondii infection in blood donors from the Brazilian Semiarid region, and to explore its implications for transfusion safety. Samples were collected from 646 donors at blood donation centers in the states of Ceará and Paraíba. Serological diagnosis was performed using BIOLISA TOXOPLASMOSE ELISA kits for anti-T. gondii IgM and IgG antibodies, and molecular diagnosis was conducted by conventional PCR targeting a 529-bp noncoding repetitive fragment. Epidemiological questionnaires on variables associated with infection were administered, and statistical analysis was performed in univariate and multivariate stages, using multiple logistic regression. Among the 646 donors, 43.4% (281/646) were positive for anti-T. gondii IgG antibodies, 0.3% (2/646) for IgM antibodies, and none tested positive by PCR. In the univariate analysis, age, family income, educational level, salad washing practices, water source, raw milk consumption, and duration as a donor were significantly associated, whereas in the multivariate analysis only “age” and “salad washing practices” remained significant. A substantial IgG seroprevalence was observed among blood donors in the Brazilian Semiarid. The low IgM frequency, concurrent IgG positivity, and negative PCR results are consistent with a low transfusion risk in the region. However, these findings should be interpreted cautiously, as negative PCR results do not completely rule out the presence of circulating parasites. Age was identified as a risk factor, whereas proper salad washing showed a protective effect. Full article

Understanding ecosystem carbon processes relies heavily on the reliable assessment of gross primary productivity (GPP) yet remains challenging in the Inner Mongolia grasslands due to data scarcity and high uncertainty among existing products. We developed a ConvTransformer-based framework that exploits complementary information from satellite observations and meteorological datasets to enhance the representation of complex spatiotemporal dependencies in grassland ecosystems. Grounded in leave-one-site-out cross-validation across six eddy covariance sites, the model achieved average performance metrics of R² = 0.59, RMSE = 1.40 g C m⁻² d⁻¹, Bias = −0.31 g C m⁻² d⁻¹, and KGE = 0.46, outperforming traditional machine learning models (RF, GBRT, and SVR) as well as the light use efficiency model (EC-LUE) in both accuracy and robustness. Using this framework, we generated a daily GPP dataset at spatial granularity of 1 km for the Inner Mongolia grasslands from 2003 to 2018. The results reveal a clear spatial gradient, with GPP decreasing from southeast to northwest. Comparisons with established products, including FLUXCOM, BESS V2, and PML V2, show strong spatial consistency and reduced discrepancies, supporting the reliability of the estimates. Overall, the proposed framework provides an effective approach for characterizing regional carbon dynamics and supports long-term ecological monitoring in semi-arid regions. Full article

Common bean (Phaseolus vulgaris L.) is a strategic crop whose sustainable production depends on symbiosis with nitrogen-fixing bacteria. However, the composition and functional potential of the nodule microbiome in varieties adapted to semi-arid regions, such as northern Mexico, remain poorly documented. Therefore, this study evaluated the influence of host genotype on nodule-associated bacterial communities in three improved varieties (Pinto Bravo, NOD1, and Jamapa) under conventional management, using high-throughput sequencing of the V3–V4 regions of the 16S rRNA gene. Alpha and beta diversity analyses showed no significant differences among varieties, indicating a similar nodular microbiome regardless of genotype. At the phylum level, Proteobacteria and Bacteroidota predominated, suggesting a conserved microbial core. At the genus level, Rhizobium was the most abundant taxon, while non-rhizobial genera such as Acinetobacter and the JC017 lineage were also detected. Functional prediction using PICRUSt2 revealed conserved metabolic profiles, with dominant pathways associated with amino acid biosynthesis, carbon metabolism, aerobic respiration, and fatty acid biosynthesis, indicating metabolic redundancy linked to tolerance to osmotic, thermal, and oxidative stress. The results suggest that under semi-arid conditions, the symbiotic interaction is governed by mechanisms at the host species level (P. vulgaris), which ensure the recruitment of a functional core microbiome, whereas intraspecific variation among improved varieties may influence the recruitment of specific accessory taxa. Full article

Artificial shelterbelts in arid and semi-arid regions play a key role in controlling land degradation, regulating wind erosion, and maintaining ecological security. However, their long-term protective effectiveness increasingly depends on accurate degradation diagnosis and targeted management of aging and degraded stands. This study developed a comprehensive health assessment and degradation grading framework for poplar shelterbelts in the Kubuqi Desert, northern China, using an indicator system covering stand structure, community structure, soil conditions, health risks, and external disturbances. Indicator weights were determined using the entropy weight method, and degradation grades were classified by combining the technique for order preference by similarity to ideal solution (TOPSIS) model with the rank-sum ratio (RSR)–Probit method. The results showed that soil conditions and stand structure were the dominant dimensions distinguishing degradation status, with weights of 50.98% and 25.30%, respectively. Grade I, Grade II, Grade III, and Grade IV stands accounted for 21.88%, 25.00%, 34.38%, and 18.75% of the plots, respectively, indicating that lightly and moderately degraded stands were predominant. Degradation grades were also associated with changes in understory cover and surface soil nutrients, especially decreases in soil organic matter and alkali-hydrolyzable nitrogen. Based on these results, grade-specific management strategies were proposed, including conservation and maintenance, density regulation, assisted restoration, and near-natural transformation. This framework provides a practical basis for diagnosing degradation status and guiding the renewal and management of aging shelterbelts in arid sandy regions. Full article

Indigenous goat populations are valuable genetic resources for livestock production in arid and semi-arid environments, yet many remain insufficiently characterized at the phenotypic and genomic levels. This study investigated phenotypic variation and genome-wide associations in two local Ardi goat lines in Bahrain: Ardi Bahraini and Ardi Mu’atar, the latter being distinguished by a characteristic facial marking pattern. A total of 280 goats were phenotypically characterized for qualitative traits and body measurements, and 76 animals were genotyped using the Illumina Caprine 60K single nucleotide polymorphism (SNP) BeadChip. After quality control, 49,716 autosomal SNPs were retained for genome-wide association analysis. Phenotypic analysis showed that the two lines differed significantly in body weight, body length, hip height, face width, tail length, ear width, and tail circumference, while discriminant analysis identified tail length, ear width, tail circumference, and facial patterns differentiating the lines. Principal component analysis (PCA) showed partial genomic clustering of the two lines, and genome-wide significant and suggestive SNPs based on Bonferroni and false discovery rate (FDR) thresholds on chromosomes 6, 13, 14, and 29. The strongest association was observed for rs268277393 on chromosome 13, located near DOK5 (Docking Protein 5) and TRNAC-GCA (transfer RNA cysteine, anticodon GCA), and was associated with the Ardi Mu’atar facial pattern. Additional candidate regions were located near genes with possible roles in pigmentation, development, or morphological variation. These findings provide preliminary genomic evidence supporting the phenotypic distinctiveness of Ardi Mu’atar goats and identify candidate markers that may contribute to future conservation and breeding programs. Further validation in larger populations and functional studies will be required to confirm the biological role of these candidate regions. Full article

Understanding dietary patterns and trophic (food) resources partitioning among sympatric mesocarnivores is important for explaining species coexistence through niche differentiation and their roles in ecosystem functioning. We analyzed the feeding ecology and dietary overlap of the golden jackal (Canis aureus) and jungle cat (Felis chaus) using scat analysis in the Kuno–Chambal ravine landscape of central India. We collected a total of 117 scat samples (96 golden jackal, 21 jungle cat) between February 2024 and April 2025 and analyzed them using micro-histological methods to quantify prey composition, frequency of occurrence, and relative biomass. We identified twenty-three prey items from the golden jackal diet. The golden jackal exhibited a generalist feeding strategy characterized by extensive use of livestock carrion (FO > 90%), contributing ~80% of prey biomass, and supplemented by plant resources (FO > 60%) and small prey (FO ~ 40%). The jungle cat consumed sixteen prey items and showed a strong dietary association with small mammals, particularly rodents (FO > 95%) and black-naped hare, which together contributed ~80% of its biomass. Standardized niche breadth was higher for the jungle cat (0.60 ± 0.07) than the golden jackal (0.37 ± 0.03), with a non-significant dietary overlap (Pianka index = 0.45). The high diversity of rodents (n = 11) in the diet of both mesocarnivores suggested their ecological importance in regulating rodent populations and golden jackals, enhancing ecosystem cleaning through their scavenging activity. Full article