Abstract. Extratropical cyclones are essential for redistributing moisture from lower latitudes to the poles, and are known for their ability to produce extreme precipitation. While wintertime extratropical cyclones have been studied in great detail, little is known about these systems in summer. Nevertheless, studying summer cyclones is particularly relevant in the context of climate change, as future warming is expected to increase atmospheric moisture while reducing baroclinicity. This makes present-day summer conditions an analogue for future winter cyclones and critical for understanding how summertime cyclones themselves may evolve in a warmer climate. Hence, the objective of this study is to improve our understanding of how summertime extratropical cyclones shape the characteristics of the water cycle, focusing on their moisture sources and the transport of moisture to cyclone centers. For this purpose, 8 d backward trajectories are calculated for all air parcels in the vicinity of cyclone centers with ERA5 reanalysis data, for a subset of the most intense summertime cyclones over the North Atlantic. Subsequently, moisture uptakes along the trajectories of precipitating air parcels are identified using the moisture source diagnostic WaterSip. Using this approach, it is found that the bulk of the precipitation associated with summertime cyclones falls close to the cyclone center beneath the warm conveyor belt (WCB) and along the fronts, mainly during the cyclone's intensification phase. This moisture originates from areas of high ocean evaporation, with significant hotspots on the warm side of the Gulf Stream Front. In addition, some continental sources are found, especially for cyclones in the Labrador Sea. Moisture uptake occurs primarily in regions where the strong sea surface temperature (SST) gradient induces intense ocean evaporation and during cold-air advection within the cyclone's cold sector, where oceanic evaporation is enhanced due to the strong air-sea temperature contrast. The moisture accumulated in the cold sector of the cyclone does not necessarily contribute to precipitation in its own center, but it can act as a source of moisture for a subsequent cyclone. As cyclones mature, distances between the moisture source and the location where the moisture rains out decrease, but the atmospheric residence time of moisture of about 4 d remains approximately the same throughout the cyclone life cycle. This is because the decrease in source distance is compensated by weaker winds and less strong convergence. Overall, these results are fairly similar to those found in a previous study for winter cyclones, although in winter there is more moisture exchange between primary and secondary cyclones, and stronger vertical ascent in the WCB. Summer cyclones, on the other hand, are distinguished by their greater moisture supply from continental sources, and the significant influence from cyclones of tropical origin undergoing extratropical transition.

This pilot study focused on the microclimate regulating effects of different vegetation types of forest-steppe habitat. Between April and December 2023, soil moisture at a depth of 10, 40 and 80 cm was measured at 3-3 sample plots alongside two natural forest edges. Between September and November 2023, air temperature and relative air humidity were recorded at 7 predefined vegetation types of sandy forest-steppe habitat (4 plots/type, 7 types/site, 3 sites, 84 plots in total). Relative soil and air humidity data was analysed with descriptive statistics, while one-way ANOVA was run for air temperature data. Our results show that the inner parts of the forests and forest edges were characterised with significantly higher soil humidity in each soil layer, compared to woodless grasslands. Furthermore, more moderate temperature is present in woody vegetation types compared to grasslands outside of forests. Significant minimum and maximum temperature-raising effects were also observed. No significant differences were detected between locations and vegetation types in air humidity, but methodological changes are necessary in the future. During the study period, microclimate of woody vegetation types was more balanced, compared to grasslands outside forests. Plots at woody vegetation types were characterised by a better soil moisture supply and a significant air temperature regulating effect, which gave a more balanced air temperature as the minimum and maximum values were more attenuated but did not influence the seasonal mean value.

Abstract The microphysical characteristics of warm‐season (April to September) heavy precipitation with respect to synoptic patterns in the Yangtze–Huaihe River Basin of China are investigated using 10 years (2014–2023) of dual‐frequency precipitation radar onboard satellite observations and principal component analysis in T‐mode classification. A total of six synoptic patterns have been identified, including the three most prevalent monsoon‐related types (T1, T2, and T3), which contributing 87% of the heavy precipitation hours. Under persistent monsoonal moisture transport in these monsoon patterns, moderate convection and warm‐rain dominance gives rise to homogeneous microphysical features characterized by high concentrations of small‐to‐medium raindrops. The perturbed synoptic patterns, including cold vortex (T4), typhoon‐influenced (T5), and weak disturbance types (T6), collectively account for 13% of events. Among them, T4 and T6 exhibit stronger convective activity, which serves to intensify ice‐phase processes, thereby producing larger raindrops with low concentration. Conversely, the substantial amount of moisture induced by typhoon flows in T5 enhances warm‐rain processes, maximizing the concentration of small raindrops. Despite these modest differences, all patterns exhibit maritime‐like microphysics with warm‐rain processes being generally dominant. Environmental analysis reveals that moisture supply and convective intensity are two major factors that regulate regional heavy precipitation microphysics through their impact on warm‐rain and ice‐phase processes at different layers. This study highlights the critical role of large‐scale circulation in shaping regional precipitation microphysics, providing observational benchmarks for comprehending precipitation extremes and model parameterization.

The study was conducted in the biocenoses of Quercus pubescens on the Southern Coast of Crimea. Six sample plots were established in the western, central, and eastern parts of the study area. The soils are predominantly brown, weakly developed on eluvium-deluvium of limestones and clay shales, while at “Cape Martyan” they are brown reddish-brown soils (Terra Rossa) formed on a thick layer of leached weathering products of Upper Jurassic limestones. The study examined the structure and composition of the phytocenosis, taxation characteristics of the stands, and specific soil conditions. It was revealed that the most stringent conditions for the characteristics of the quality of the soil environment are currently developing in the western part of Q. pubescens growth on the Southern Coast of Crimea. The soil under Laspi and Kastropol plantings have the lowest humus concentration and moisture content. In the central part of the Q. pubescens forest, with some improvement in soil conditions, the general specificity of changes in the quality of the soil environment is very close to the plantings of the western territories. It was found that the growth and development of Q. pubescens stands on Cape Ai-Todor are largely determined by the seasonal dynamics of soil moisture. The relatively high moisture content in the soil during the first months of vegetation has a positive effect on the growth of Q. pubescens ; and its sharp decrease in the second half of summer to values, close to the indicators of the biocenoses of the western part, shows a stressful effect on the condition of the forest stands on Cape Ai-Todor. In the eastern part of Q. pubescens habitat on the Southern Coast of Crimea, the underlying bedrock has a significant effect on soil conditions. Gabbro-diabase of the Ayu-Dag and Kastel laccoliths affects soil acidity, features of humus formation and accumulation. It is shown that dense gabbro-diabase layers increase moisture supply of Q. pubescens stands in the Ayu-Dag and Kastel ecotopes. It is concluded that the total cutting of primary Q. pubescens stands on the Southern Coast of Crimea in the past determined the deep degradation of the structure and composition of plant communities, the formation of low-productivity coppice plantations in these areas. One of the causes of destructive phenomena in the development of Q. pubescens biocenoses is a change in the water balance of the soil environment. The growth potential of Q. pubescens coppice stands on the Southern Coast of Crimea is currently provided by the powerful root system of the parent tree stand, which continues to function.

The sowing process must ensure that the seeds are distributed well over the seedbed, thus providing each seed with nutrients and moisture. The initial uniform flow of seeds is created in the seeding unit of the seeder, where the seeds are placed evenly on the seeding element, transported to the discharge zone and directed to the furrow. An important condition for the coulter to work is not only to create a furrow, but also to maintain a uniform flow of seeds and to place individual seeds at the bottom of the furrow at equal distances from each other and to cover them. Therefore, the choice of a coulter in accordance with the chosen cultivation technology of the respective crop and soil and climatic conditions is an important task. Providing seeds with the best conditions for their development is the link that connects high-quality sowing with a good harvest. According to the technological principle, the coulters are divided into three groups: with a sharp, blunt and straight angle of entry into the soil. Coulters with a sharp angle of penetration (anchor and tine coulters) form a furrow by moving the soil layer from the bottom up, resulting in a loose furrow bottom. Ploughshares with an obtuse angle of penetration (keel, skid and disk) create a furrow by pressing the soil layer from top to bottom, thus creating a compacted furrow bottom. Coulters with a straight angle of entry into the soil (tubular) push the soil layers apart, forming a furrow. The main advantages and disadvantages of each type of coulter are analyzed and determined. The possibilities of different cultivation technologies and different soil and climatic conditions are analyzed. To ensure the quality of the sowing process, when choosing the right sowing unit and coulter group, it is necessary to accurately assess the climatic conditions, soil type and its physical and mechanical properties, moisture supply and field topography. The use of continuous and strip sowing will increase sowing productivity due to the higher speed of the sowing unit and preserve moisture in the soil. Therefore, taking into account the above factors, we will be able to choose the right coulter for the appropriate technology for growing a particular crop.

The results of the study of the inheritance of the main economically valuable traits of barley in the reciprocal crossing system and the assessment of the combination ability of seed parents in the conditions of the Krasnoyarsk forest-steppe in 2023–2024 are presented. The objects of research were 6 varieties of Siberian spring barley, 1 foreign variety and 12 F 1 hybrids created on their basis. The soil of the experimental field was thin common chernozem. The forecrop was complete fallow. The content of humus in the soil was 3,4–4,0%, nitrate nitrogen – 5,3–5,7 mg/kg of soil, phosphorus – 18,8–22,2 mg/100 g of soil, potassium – 13,7–15,0 mg/100 g of soil. In terms of heat and moisture supply, 2023 was characterized by dry conditions with the HTC of 0.86, while 2024 was excessively humidified with the HTC of 1.86. Sowing was carried out at the optimal time for the culture on May 25–27. The feeding area of the plant was 2×20 cm. The repetition was 3-fold. According to the results of the assessment, the varieties showed a reliably high total combination ability only by the number of grains per ear. This feature was inherited mainly by the type of positive overdomination – 50.0% of the combinations (H p ˃ + 1.00). The varieties of spring barley Takmak, Olenek and Talan showed a high total combination ability by the ear grain content (g i = 0,36–0,96) and a lower specific combination ability (σ 0,06–0,49) in all years of the study, which indicates the prospects for using these varieties in heterosis selection. Promising hybrid combinations with a complex of economically valuable traits have been identified: Buyan × Salome, Salome × Buyan, Olenek × Salome, Salome × Abalak, Takmak × Salome, Salome × Takmak.

A moisture‐induced power generator (MPG) with exceptionally high‐power output and extended operational stability is developed by systematically integrating three active materials: A LiCl ‐containing hydrogel, a perforated aluminum sheet, and NaV3O8 (NVO) nanobelts. The LiCl‐containing hydrogel, due to its hygroscopic nature, maintains a stable moisture gradient and supplies charge carriers (Li+ ions). Simultaneously, the perforated aluminum sheet acts as the primary source of charge carriers (Al3+ ions) without generating oppositely charged ions, thereby preventing the degradation of the potential difference caused by ion migration. The NVO nanobelts undergo a reduction reaction through the intercalation of Li+ and Al3+ ions into their layered structure, effectively preventing reverse migration by resolving charge accumulation and generating Faradaic currents. Furthermore, their elongated structure enables the formation of a high‐surface, conductive active layer through entanglement with carbon black nanoparticles, eliminating the need for binder materials. This systematic design achieves a maximum open‐circuit voltage of 1.64 V, a short‐circuit current of 10.44 mA cm−2, and a power density of 2.13 mW cm−2 at a load resistance of 200 Ω under 90% relative humidity. These results represent a record‐high performance among reported MPGs, highlighting significant advancements in efficiency and durability, thereby enhancing the feasibility of MPGs for practical applications.

Rainfall remains the primary supply of moisture for agricultural activities in Nigeria. Accurate and timely rainfall prediction is also essential for food security, better flood control, water resource management, and the wellbeing of the people. This research proposes a method for rainfall prediction based on metrological data and a machine learning technique. The machine learning technique is a hybrid of Levenberg-Marquardt (LM) back propagation and Artificial Neural Network (ANN) used to construct the rain fall forecasting model. Anyigba, in Dekina Local Government Area, Kogi State, Nigeria was used as a case study. The database from six years (2011-2016) of meteorological parameters made up of air temperature, relative humidity, and pressure were obtained from the Tropospheric Data Acquisition Network (TRODAN) of the Centre for Atmospheric Research, National Space Research and Development Agency (CAR-NASRDA) and used. The rainfall prediction model was trained using part of the data collected. The performance of the model was evaluated using metrics such as precision, recall, F1-score, and confusion matrix. The model achieved an accuracy of 0.88, indicating its robustness and reliability in predicting rainfall patterns. The high accuracy of the model demonstrates its potential application in real-time weather prediction, which can significantly benefit local farmers, water resource managers, and disaster response teams. The study identifies several limitations, including the dependency on the quality and availability of metrological data, and the potential impact of climate change on predictive accuracy. Future research could explore the integration of additional meteorological parameters, the use of ensemble methods, and the adaptation of the model to other regions with similar climatic conditions. This research presents a promising approach to rainfall prediction in Anyigba using the back propagation algorithm, offering a valuable tool for mitigating the adverse effects of unpredictable rainfall and enhancing the decision-making processes in agriculture and water management.

The study is aimed at identifying the relationships between the natural and climatic conditions of small-leaved linden growth sites and their nectar productivity. During a comparative assessment of the nectar productivity of small-leaved linden plantations and hydrometeorological data (hydrothermal coefficient (HTC), Pedya Aridity Index) from 2018 to 2023 in the territories of protected areas located in different natural and climatic conditions of the Republic of Bashkortostan, it was found that in 2019 there were the most optimal conditions for nectar secretion of linden plantations. In the fall of 2018, according to the Pedya Index, it was noted that in the Zilim Nature Park, during the entire warm period, there were "normal moisture conditions", which made it possible to obtain maximum nectar production in 2019 under conditions of optimal moisture supply (HTC = 1.81) was 397.2 ± 39.7 kg/ha. In the Shaitan-Tau Nature Reserve in 2019, during the linden flowering period, drought conditions observed, according to the Pedya Index, and nectar production was only 232.8 kg/ha. Optimal hydrothermal conditions allow plants to develop well and produce more nectar. Hydrometeorological indicators of the previous year can be used to predict potential nectar productivity in the current year. For example, if the previous year was wet and warm, this can have a positive effect on flowering and nectar secretion in the current year.

Abstract Understanding the atmospheric drivers of extreme rainfall is essential for improving regional adaptation strategies. In Central Africa, previous studies widely emphasize large‐scale influences, often overlooking complex regional processes. In this study, we combined the capacity of vertically integrated moisture flux convergence (VIMFC) to capture information from the entire atmospheric column with the ability of convolutional neural networks to learn complex, nonlinear patterns from large and intricate data sets, thereby unlocking VIMFC's potential as an effective regional predictor. Our machine learning model successfully identifies 95% of observed extreme rainfall events using VIMFC as input. The CNN's predictions, interpreted using the layer‐wise relevance propagation method, highlight its ability to capture spatiotemporal distributions of strong moisture convergence and divergence linked to extreme rainfall and drought events. Over the past two decades, we have observed a clear increase in the frequency of extreme precipitation moisture flux patterns (EPMFPs), which aligns with rising extreme rainfall occurrences. On EPMFP days, we detect stronger low‐level moisture inflow from the Atlantic Ocean and enhanced moisture supply driven by a deeper and more intense Congo Basin convective cell. This is supported by evapotranspiration from the basin's dense vegetation, acting as a continental moisture reservoir. Midlevel analysis reveals more moisture retention over the region during EPMFPs, linked to the positioning and strength of the African easterly jets. While both EPMFP and non‐EPMFP composites show similar meridional moisture transport, distinct zonal moisture outflow and inflow patterns highlight the dynamical differences between the two regimes.

Abstract Despite high confidence in the intensification of the hydrological cycle due to global warming, the future spatiotemporal patterns of extreme precipitation remain uncertain. Here we explore how climate change influences the seasonal timing of extreme precipitation events, using daily output from the Coupled Model Intercomparison Project Phase 6. We show that at latitudes between about 45°N and 75°N in Eurasia and North America, where extreme precipitation typically peaks in summer, climate models project a substantial shift in the seasonal timing of extreme precipitation from summer into the colder seasons, spring and autumn, or even into winter, by the late 21st century. We show that this shift is associated with reduced moisture supply during strong updraft events in summer. These results point towards a need for improved representations of processes determining the change in the moisture availability and simulated vertical winds of the atmosphere as well as for adaptation to higher flood risk in colder seasons.

The concrete components of two commercial buildings corresponding to extreme cases in terms of aggregate pyrrhotite content and soil conditions, were investigated. Unlike the above-ground concrete of foundation walls exposed to climatic conditions, the concrete of such walls and footings buried on both sides, at least more than 30 cm in depth, is undamaged, has a high water saturation degree, and contains pyrrhotite that is not at all or almost non-oxidized. The water saturation degree of this concrete is too high for the pyrrhotite it contains be sufficiently oxidized. For damage to occur, the original concrete must first dry sufficiently for the pyrrhotite be oxidized, and then, external moisture supplies are needed for expansive sulfates be formed. The on-ground, structural and steel-deck slabs analyzed, whatever their covering (bare, vinyl or ceramic), were undamaged, except locally where they were frequently exposed to water.

In the summer of 2022, central and eastern China experienced prolonged extreme high temperatures and severe drought, leading to significant economic losses. To gain a more profound understanding of this drought event and furnish a reference for forecasting similar events in the future, this study examines the circulation anomalies associated with the drought. Employing a diagnostic method focused on temperature and moisture anomalies, this study introduces a novel approach to quantify and compare the relative significance of moisture transport and warm air dynamics in contributing to the drought. This study examines the atmospheric circulation anomalies linked to the drought event and compares the relative contributions of water vapor transport and warm air activity in causing the drought, using two parameters defined in the paper. The results show the following: (1) The West Pacific Subtropical High (WPSH) was more intense than usual and extended westward, consistently controlling the Yangtze River Basin. Simultaneously, the polar vortex area was smaller and weaker, the South Asian High area was larger and stronger, and it shifted eastward. These factors collectively led to weakened water vapor transport conditions and prevailing subsiding air motions in the Yangtze River Basin, causing frequent high temperatures. (2) By defining Iq and It to represent the contributions of moisture and temperature to precipitation, we found that the drought event in the Yangtze River Basin was driven by both reduced moisture supplies in the lower troposphere and higher-than-normal temperatures, with temperature playing a dominant role.

Abstract Southwest China (SWC) experienced a persistent extreme drought event from January to May 2023, with extensive and severe drought conditions peaking in January, April, and May. During these peak months, the standardized precipitation evapotranspiration index anomalies exceeded −1.5 standard deviations, indicating the extreme seasonal drought. Analysis revealed that anomalous descending motion and suppressed moisture transport resulted in precipitation deficit and enhanced potential evapotranspiration, further causing the prolonged drought. Specifically, in January 2023, reduced snow cover in southern Europe induced mid‐upper tropospheric high‐pressure anomalies over the Tibetan Plateau and SWC and enhanced Ural blocking high, contributing to anomalous northerly cold winds and subsidence. Simultaneously, cold sea surface temperature (SST) anomalies in the tropical western Indian Ocean weakened the south branch trough (SBT), further limiting moisture supply. These factors resulted in cold and dry conditions across SWC. In April, decreased snow cover in northern Europe excited upper‐level Rossby waves, favoring positive geopotential height anomalies and anomalous descending motions over SWC. These conditions, combined with a weakened SBT linked to warm SST anomalies in the Arabian Sea, suppressed precipitation in SWC. Additionally, strong local land‐atmosphere interactions and subsidence‐induced diabatic warming increased surface air temperature, exacerbating high temperature and drought conditions in April. In May, mid‐upper tropospheric high‐pressure anomalies over SWC linked to dry soil moisture in western Siberia and a weakened SBT associated with southern Indian Ocean SST anomalies, together with local land‐atmosphere coupling, sustained dry and hot conditions in SWC. Numerical experiments further confirmed the above physical mechanism.

Abstract The onset of the South China Sea (SCS) summer monsoon (SCSSM) has considerable impacts on the weather and climate in East Asia and beyond. Southern China often experiences persistent heavy rainfall during the SCSSM onset, and this rainfall can be attributed to the 10–30-day intraseasonal oscillation (ISO) originating from the equatorial western Pacific and propagating northwestward. Before the monsoon onset, the SCS is controlled by a strong negative phase of ISO featured by an anomalous low-level anticyclone while active convection dominates the Bay of Bengal (BOB). In this condition, anomalous southwesterlies at the northwestern flank of the SCS anticyclone carry abundant water vapor to southern China. Meanwhile, the convective forcing over the BOB moves to the southern Tibetan Plateau and triggers an anomalous upper-tropospheric anticyclone. This anticyclone extends downstream with the background westerlies and brings northerly anomalies to southern China, inducing anomalous ascending motions through altering potential vorticity advection. Thus, the negative phase of ISO induces heavy rainfall in southern China through enhancing both moisture supply and ascending motions. When the ISO evolves into a positive phase, convective activity and low-level westerlies intensify over the SCS, indicating the onset of the SCSSM. Afterward, the above dynamic and thermodynamic conditions over southern China are reversed and then the heavy rainfall recedes. We highlight that the ISO not only plays a significant role in triggering the onset of the SCSSM but also causes a persistent heavy rainfall process in southern China during the monsoon onset. Significance Statement Persistent heavy rainfall in southern China can have significant societal impacts, including severe floods, agricultural damage, and human health. It is found that during the onset of SCSSM, southern China often experiences persistent heavy rainfall lasting nearly 1 week, characterized by a significant increase before monsoon onset but a quick reduction afterward. Why is this heavy rainfall process generated during the SCSSM onset and how does it quickly decay afterward? We emphasize the key role of the 10–30-day intraseasonal oscillation (ISO) originating from the equatorial western Pacific in triggering this persistent heavy rainfall process. This study helps to improve the understanding of the SCSSM onset and its relationship with the weather and climate in southern China.

Anomalous oceanic moisture supply conceals expected stable water isotopic depletion during monsoon extreme rain events in Kerala, India.

The excellent moisture transport properties of yarns play a crucial role in improving the liquid moisture transfer behavior within textiles and maintaining their thermal-wet comfort. However, the current research on the moisture management performance of fabrics made from yarns with excellent liquid transport properties primarily compares the wicking results, without considering the varying requirements of testing conditions due to differences in human sweating rates during daily activities. Moreover, the understanding of moisture transport mechanisms in yarns within fabrics under different testing conditions remains insufficient. In this study, two types of twisted combination yarns, composed of hydrophobic profiled polyester filaments and hydrophilic spun yarns to form a hydrophobic-hydrophilic gradient along the axial direction of the yarn, were developed and compared with profiled polyester filaments to understand the liquid migration behaviors in the knitted fabrics formed by these yarns. Results showed that hydrophobic profiled polyester filament yarn demonstrated superior liquid transport performance with infinite saturated liquid supply (vertical wicking test). In contrast, the twisted combination yarns exhibited better moisture diffusion properties under limited liquid droplet supply conditions (droplet diffusion test and moisture management test). These contradictory findings indicated that the amount of liquid moisture supply in testing conditions significantly affected the moisture transport performance of yarns within fabrics. It was revealed that the liquid moisture in the twisted combination yarns migrated through capillary wicking for moisture transfer. Under an infinite saturated liquid supply condition, the higher the content of hydrophilic fibers in the spun yarns, the greater the amount of moisture transferred, demonstrating an excellent liquid transport performance. Under the limited liquid droplet supply conditions, both the volume of liquid water and the moisture absorption capacity of the yarn jointly influence internal moisture migration within the yarn. It provided a theoretical reference for testing the internal moisture wicking performance of fabrics under different states of human sweating.

Stable oxygen isotopes in tree rings (δ18O) serve as important proxies for climate change and offer unique advantages for climate reconstruction in arid and semi-arid regions. We established an annual δ18O chronology spanning 1964–2023 using Juniperus excelsa tree-ring samples collected from the Alborz Mountains in Iran. We analyzed relationships between δ18O and key climate variables: precipitation, temperature, Palmer Drought Severity Index (PDSI), vapor pressure (VP), and potential evapotranspiration (PET). Correlation analysis reveals that tree-ring δ18O is highly sensitive to hydroclimatic variations. Tree-ring cellulose δ18O shows significant negative correlations with annual total precipitation and spring PDSI, and significant positive correlations with spring temperature (particularly maximum temperature), April VP, and spring PET. The strongest correlation occurs with spring PET. These results indicate that δ18O responds strongly to the balance between springtime moisture supply (precipitation and soil moisture) and atmospheric evaporative demand (temperature, VP, and PET), reflecting an integrated signal of both regional moisture availability and energy input. The pronounced response of δ18O to spring evaporative conditions highlights its potential for capturing high-resolution changes in spring climatic conditions. Our δ18O series remained stable from the 1960s to the 1990s, but showed greater interannual variability after 2000, likely linked to regional warming and climate instability. A comparison with the δ18O variations from the eastern Alborz Mountains indicates that, despite some differences in magnitude, δ18O records from the western and eastern Alborz Mountains show broadly similar variability patterns. On a larger climatic scale, δ18O correlates significantly and positively with the Niño 3.4 index but shows no significant correlation with the Arctic Oscillation (AO) or the North Atlantic Oscillation (NAO). This suggests that ENSO-driven interannual variability in the tropical Pacific plays a key role in regulating regional hydroclimatic processes. This study confirms the strong potential of tree-ring oxygen isotopes from the Alborz Mountains for reconstructing hydroclimatic conditions and high-frequency climate variability.

Lentil is a valuable legume, widely spread throughout the world. In the Republic of Bashkortostan, agricultural producers do not have much interest in cultivating lentil due to its low productivity, primarily due to the insufficient number of varieties adaptable to the conditions of the region. In this regard, the purpose of the current study was to estimate lentil varieties by the most important traits and properties to select the most suitable ones for the Cis-Urals. The trials were conducted in 2022–2024. Weather conditions were contrasting by the years, since 2023 and 2024 were arid (HTC = 0.52 and HTC = 0.71, respectively), 2022 was favorable due to moisture supply and temperature conditions (HTC = 1.30). The estimation, records and measurements were carried out in accordance with the Methodology of the state variety testing of agricultural crops. The lentil varieties ‘Vekhovskaya 1’, ‘Ekaterinovskaya’, ‘Rauza’, ‘Danaya’, ‘Oktava’, ‘Pikantnaya’, ‘Nevesta’, ‘Lira’ were the material for the current study. The results of our trials have shown that in 2022–2024, the earliest ripening varieties were ‘Pikantnaya’, ‘Danaya’, ‘Vekhovskaya 1’ with the length of a vegetation period of 74.3±1.5; 74.0±2.0; 75.3±2.5 days, respectively. The technologically efficient varieties with high attachment of lower beans were ‘Ekaterinovskaya’, ‘Oktava’, ‘Nevesta’, ‘Danaya’, ‘Pikantnaya’. High seed productivity was established in the varieties ‘Ekaterinovskaya’, ‘Oktava’, ‘Nevesta’ with 2.06±0.11; 1.94±0.04; 1.94±0.09 g of seed per plant, respectively. According to the Competitive Variety Testing data, on average over 3 years, the greatest grain yield increase was given by the varieties ‘Nevesta’ (+0.16 t/ha), ‘Ekaterinovskaya’ (+0.15 t/ha), ‘Oktava’ (+0.12 t/ha). The results obtained allow recommending the most adaptive and highly productive lentil varieties ‘Ekaterinovskaya’, ‘Nevesta’, ‘Oktava’ for cultivation in the Republic of Bashkortostan.

In arid agricultural production, exploring suitable water-saving irrigation strategies and analyzing their water-saving mechanisms are of great significance. Alternating partial root-zone drying irrigation (APRI), a water-saving strategy, enhances the water use efficiency (WUE) of alfalfa (Medicago sativa L.) This paper aims to clarify the physiological mechanisms by which the APRI method enhances the physiological WUE of alfalfa, as well as the differences between this water-saving irrigation strategy, conventional irrigation (CI), and their water deficit adjustments, in order to seek higher water use efficiency for alfalfa production in arid regions. In this experiment, alfalfa was used as the research subject, and three irrigation methods, CI, fixed partial root-zone drying (FPRI), and APRI, were set up, each paired with three decreasing moisture supply gradients of 90% water holding capacity (WHC) (W1), 70% WHC (W2), and 50% WHC (W3). Samples were taken and observed once after every three complete irrigation cycles. Through a comparative analysis of the growth status, leaf water status, antioxidant enzyme activity, and osmotic adjustment capabilities of alfalfa under different water supplies for the three irrigation strategies, the following conclusions were drawn: First, the APRI method, through artificially created periodic wet–dry cycles in the rhizosphere soil, provides pseudo-drought stress that enhances the osmotic adjustment capabilities and antioxidant enzyme activity of alfalfa leaves during the early to middle phases of irrigation treatment compared to CI and FPRI methods, resulting in healthier leaf water conditions. Secondly, the stronger drought tolerance and superior growth conditions of alfalfa under the APRI method due to reduced water availability are key factors in enhancing the water use efficiency of alfalfa under this strategy.