Dry Climatic Conditions Research Articles

The success of ecological engineering projects on vegetation restoration in China strongly depends on climatic conditions

China has implemented extensive ecological engineering projects (EEPs) during recent decades to restore and enhance ecosystem functioning. However, the effectiveness of these interventions can vary due to factors such as local climate and specific project objectives. Here, we used two independent satellite remote sensing datasets, including the Global Inventory Monitoring and Modeling System (GIMMS) Normalized Difference Vegetation Index (NDVI) and vegetation optical depth from Ku-band (Ku-VOD), to investigate the vegetation trends in two hotspot regions of EEPs characterized by different climate conditions, i.e., the xeric/semi-xeric Loess Plateau and mesic southwest China. We found diverging vegetation greenness/biomass trend shift patterns in these two regions as a result of the combined effects of EEPs and climate variations, as indicated by changes in the Standardized Precipitation Evapotranspiration Index (SPEI). In the Loess Plateau, where no significant climate variations were observed, NDVI/Ku-VOD increased continuously after the implementation of key EEPs in 2000. Conversely, southwest China has experienced persistent drying since 2000, and vegetation greenness/biomass showed an increasing trend during the initial stages of ecological engineering implementation but subsequently reversed towards a decline due to the continued dry climatic conditions. We used the residual trend method to separate the influence of EEPs from climate variations on vegetation trends and found a positive effect of the ecological management practices in the Loess Plateau, yet a predominantly negative effect in the southwest China region, which means that projects implemented in southwest China did not lead to a long-term improvement in vegetation growth under the given climate conditions in southwest China. This adverse impact suggests that ecological engineering practices could potentially increase the ecosystem's vulnerability to droughts, owing to the increased transpirational water demands introduced by ecological engineering interventions. Our study highlights the importance of considering the expected occurrence and magnitude of climatic variability when implementing large-scale EEPs.

Assessment of annual performance of quonset GiPVT system combined with an earth-air heat exchanger (EAHE) for hot and dry climatic conditions

Annual performance of a Quonset-shaped GiPVT system combined with an earth air heat exchanger (EAHE) has been evaluated for hot and dry climatic conditions. A periodic thermal model for the GiPVT system has been developed in terms of input climatic and design parameters by employing the energy balance equations of the greenhouse system. The present model is used to calculate the effective cooling and heating capacity of the EAHE, which is further utilized to determine the optimum operating hours of EAHE for different months of the year. Furthermore, the electrical energy of the GiPVT system and the thermal energy of EAHE are calculated, enabling a comprehensive performance evaluation of the greenhouse system. Results show that the EAHE increases the greenhouse air temperature by 8 °C on the coldest day and decreases the greenhouse air temperature by 21 °C on the hottest day of the year. EAHE has a lower potential for heating than cooling because of the hot and dry climatic conditions. Moreover, the system generates 17.6 kWh and 29.22 kWh of electrical energy on an extremely cold and hot day, respectively making the system self-sustainable. The EAHE significantly reduced TLL and DF values, which gives thermal comfort to the greenhouse.

Climate-adaptive strategies for enhancing agricultural resilience in southeastern coastal Bangladesh: Insights from farmers and stakeholders.

Climate change impacts crop production worldwide, and coastal regions are particularly vulnerable to its adverse effects. Given the projected rise in temperature and shifting precipitation patterns, it is crucial to examine the current challenges faced by farmers in coastal Bangladesh. Using Focus Group Discussions (FGDs) and Key Informant Interviews (KIIs), we assessed the perceptions and experiences of farmers and stakeholders regarding the existing agricultural practices, the challenges they face in crop cultivation, and the adoption of climate-adaptive practices in 2 sub-districts in the southeastern coastal region of Bangladesh. Moreover, using the Standardized Precipitation Evapotranspiration Index (SPEI) and the Standardized Terrestrial Water Storage Index (STI), we assessed the frequency and intensity of different climatic conditions in these two sub-districts. Results show that 100% of the respondents reported an increase in dry climatic conditions, the occurrence of untimely precipitation, and a decline in irrigation water during the cropping season. All the respondents in the FGDs expressed a loss of crop production because of these climate-induced disturbances. Despite these challenges, farmers have been implementing several climate-adaptive practices. Among the 9 mentioned climate-adaptive practices, 50% of FGD respondents utilize organic fertilizers, 42% cultivate heat- and drought-resilient crop varieties, use improved irrigation and harvest rainwater, and 25% cultivate integrated crops. The results of quantitative analysis of 3- and 6-month SPEI and STI values show that this region experienced frequent and intense dry climatic conditions during the growing-season, which supports the farmers' and stakeholders' concern about the increasing occurrence of droughts during crop growing periods. The results suggest that despite adopting climate-resilient practices under increasing growing-season droughts, farmers require support from the government and NGOs in capacity-building training and input support (e.g., stress-resilient seeds). This study holds practical implications for government, NGOs, and policymakers for ensuring sustainable agricultural productivity in the coastal region of Bangladesh.

Analysis of Climate Variability and Its Implications on Rangelands in the Limpopo Province

In recent decades, southern Africa has experienced a shift towards hotter and drier climate conditions, affecting vital sectors like agriculture, health, water, and energy. Scientific research has shown that the combination of high temperatures and unreliable rainfall can have detrimental effects on agricultural production. Thus, this study focused on assessing climate variability, with implications on rangelands in the Limpopo Province of South Africa over 38 years. Historical climate data from 15 stations, including rainfall and minimum and maximum temperatures from 1980 to 2018, were analysed. To achieve the main objective, various statistics including mean, standard deviation, and coefficient of variation (CV) were computed for all variables across four seasons. The results highlighted significant variability in rainfall, with Musina (71.2%) and Tshiombo (88.3%) stations displaying the highest variability during the September-to-April season. Both minimum and maximum temperatures displayed low variability. The Mann–Kendall test revealed both increasing and decreasing trends in minimum temperatures and rainfall across different stations. Notably, there was a significant increase in maximum temperatures. This study provides valuable climate information for decision makers, aiding in the planning and management of agricultural activities, particularly in understanding how climate variations affect forage availability in rangelands.

Holocene geochronology and sedimentation in the southern Brazil shelf depocenters

Latitudinal modulation of proxies for environmental changes over the mid to late-Holocene was analyzed in four cores retrieved along mud depocenters on the South Brazilian Shelf, between 33.8°S and 25.1°S. To the south, early to mid-Holocene northwards migrations of the Southern Westerly Wind Belt (SWWB) and the post-LGM sea level rise are expressed as an increase in sand content, while the low Ti/Ca and Ti/K ratios point to dry climatic conditions. During the mid-Holocene, the sea level highstand coincided with a period of stabilization in atmospheric conditions, which led to a pulse of coarser sediment deposition in the southern area. In 3000 cal yr BP, a rapid and latitudinally simultaneous increase of Ti/Ca and Ti/K mark the late-Holocene more humid and warmer onset linked to an intensification of the South American Monsoon System (SAMS). Across-shelf branches of the Brazil Current (BC) that mix with the Plata Plume Water (PPW) to flow northwards could be responsible for sediment remobilization leading to clay depletion in the south extreme of the study area. The amplitude of grain size changes gets lower as we go further north, suggesting a buffering effect exerted by the distance to the source.

Impacts of environmental feedbacks on the production of a Central Queensland beef enterprise in a future climate

CONTEXTUnderstanding climate change impacts on beef production enterprises in northern Australia is challenging due to the complexity of the system, which involves biophysical processes such as pasture and animal production, herd management, economics, emissions, and the interaction among these things. Modelling is a powerful tool to help the beef industry understand the impacts of climate change and to develop adaptation plans to help ensure enterprises remain economically viable over the long term. OBJECTIVEWe assess climate change impacts on a single specialised beef enterprise south-east of Moura (24.59°S, 150.09°E) in northern Australia's Central Queensland region. This is achieved by comparing enterprise performances during a 2030s climate and a 1975–2013 baseline period. METHODSWe used a calibrated pasture model called GRASP to simulate the farm's pasture growth under multiple scenarios for land conditions, grass basal areas and stocking rates for the baseline and 2030s climates and to construct pasture growth databases – known as datacubes. The datacubes provide a simplified representation of mean coupling between the herd dynamics and livestock production model (Crop Livestock Enterprise Model). The coupled whole-of-farm model was parameterised using enterprise data collected through interviews with the property owner and allowed for feedback between the pasture and livestock systems. The feedback capability allowed us to consider changes in land condition through stocking rates and their effect on pasture growth, animal weight gain, profit and CO2 emissions. RESULTS AND CONCLUSIONSWe found that warmer and drier climatic conditions during 2030s will reduce pasture growth in austral spring and summer but increase pasture growth in winter and autumn. Increased pasture growth in winter and autumn cannot compensate for the reduction in pasture growth in the warm seasons but can improve animal liveweight gain in winter and early spring. This leads to an overall increase in annual weight gain of steers (the cattle class that provides the main income source for this farm) while the CO2 emission intensity remains similar to the baseline period. Maintaining land condition under the 2030s climatic conditions considered will require a reduction in sustainable herd size, leading to lower beef production and lower profit under current pasture and herd management strategies. Impacts will likely differ from those described if a drier future is not realised. SIGNIFICANCEThis study provides a climate change impact assessment on a specialised beef enterprise (i) being distilled from individual ruminants, and (ii) considering environmental feedbacks in the interaction between pasture and livestock systems.

Fire activities and their impacts on local ecosystems in the southern Ordos Basin during the Middle Jurassic: Evidence from pyrogenic PAHs and petrography of inertinite-rich coal

The high frequency of fires during the formation of some mire systems in the Jurassic is thought to have influenced how terrestrial ecosystems evolved. Ancient mires, now present as coal seams, contain high-resolution paleoenvironmental and paleoclimatic records. Thus, the analysis of coal beds provides valuable, insightful, and practical knowledge on the changes in paleoclimate and, in this case, fire prevalence. Using petrographic, carbon isotopic, mercury content, and polycyclic aromatic hydrocarbon (PAH) determinations, the Middle Jurassic No. 4 coal from the Binchang region in the Ordos Basin was examined in order to understand the nature of fire during the formation of the mires. The results show that the No. 4 coal exhibits a high content of inertinite (average content 70%). Notably, the correlation coefficient (r = 0.79) between the concentration of PAHs (with >3 rings) and the proportion of inertinite indicates that the high content of inertinite was predominantly the result of fire. The presence of natural char and coke in the coals further indicates the frequent incidence of fires during the Middle Jurassic in the southern Ordos Basin. High frequency of fires can be attributed to the availability of fuel (i.e., the buildup of organic material), high atmospheric oxygen levels, and intermittent dry climatic conditions. The random reflectance of inertinite (specifically, fusinite and semifusinite) in the No. 4 coal bed ranges from 1.25% to 2.45%, which, with the presence of pyrogenic PAHs, suggests that their formation may have been predominantly affected by low- and moderate-temperature fires. The high frequency of fires is thought to have significant impacts on terrestrial and hydrological ecosystems. These effects may have included the circulation of atmospheric mercury, as well as the possible occurrence of anoxic events in the lakes.

Data‐driven modeling to enhance municipal water demand estimates in response to dynamic climate conditions

AbstractAltered precipitation and temperature patterns from a changing climate will affect supply, demand, and overall municipal water system operations throughout the arid western U.S. While supply forecasts leverage hydrological models to connect climate influences with surface water availability, demand forecasts typically estimate water use independent of climate and other externalities. Stemming from an increased focus on seasonal water demand management, we use the Salt Lake City, Utah municipal water system as a test bed to assess model accuracy versus complexity trade‐offs between simple climate‐independent econometric‐based models and complex climate‐sensitive data‐driven models to average to extreme wet and dry climate conditions—representative of a new climate normal. The climate‐independent model displayed low performance during extreme dry conditions with predictions exceeding 90% and 40% of the observed monthly and seasonal volumetric demands, respectively, which we attribute to insufficient model complexity. The climate‐sensitive models displayed greater accuracy in all conditions, with an ordinary least squares model demonstrating a measurable reduction in prediction bias (3.4% vs. −27.3%) and RMSE (74.0 lpcd vs. 294 lpcd) compared to the climate‐independent model. The climate‐sensitive workflow increased model accuracy and characterized climate‐demand interactions, demonstrating a novel tool to enhance water system management.

Design, construction and operation issues of reinforced concrete bridge structures in dry hot climate conditions of the Republic of Uzbekistan

It is noted that in Uzbekistan the climate is dry and hot, the region itself is seismically active, which imposes special requirements to design, construction and operation of bridges. Characteristic types of reinforced concrete bridge superstructures in the republic are given. Peculiarities of reinforced concrete application in conditions of dry hot climate are considered. Recommended methods of reducing negative effects when creating reinforced concrete structures and advantages of using monolithic concrete in bridge construction in Uzbekistan are described. Characteristic damages of Uzbekistan reinforced concrete bridge structures are considered and examples of their manifestation on bridges are given. Maintenance organization peculiarities in the republic are analyzed and three operation periods are considered (before 1955, from 1955 to 1990, and after 1991 up to the present time). Further the disadvantages of the calculation by limit states method are analyzed, and the necessity of deformation approach application is discussed, according to which to the known three sides of the structures calculation problem: static, geometrical and physical are added equations describing kinetics of structures interaction processes and their constituent materials with aggressive external media and fields, dependences connecting characteristics of structure materials with external influences parameters, and equations describing damages development, leading to the gradual collapse of the structure.

Exploring Climate Sensitivity in Hydrological Model Calibration

In the context of hydrological model calibration, observational data play a central role in refining and evaluating model performance and uncertainty. Among the critical factors, the length of the data records and the associated climatic conditions are paramount. While there is ample research on data record length selection, the same cannot be said for the selection of data types, particularly when it comes to choosing the climatic conditions for calibration. Conceptual hydrological models inherently simplify the representation of hydrological processes, which can lead to structural limitations, which is particularly evident under specific climatic conditions. In this study, we explore the impact of climatic conditions during the calibration period on model predictive performance and uncertainty. We categorize the inflow data from AnDong Dam and HapCheon Dam in southeastern South Korea from 2001 to 2021 into four climatic conditions (dry years, normal years, wet years, and mixed years) based on the Budyko dryness index. We then use data from periods within the same climatic category to calibrate the hydrological model. Subsequently, we analyze the model’s performance and posterior distribution under various climatic conditions during validation periods. Our findings underscore the substantial influence of the climatic conditions during the calibration period on model performance and uncertainty. We discover that when calibrating the hydrological model using data from periods with wet climatic conditions, achieving comparable predictive performance in validation periods with different climatic conditions remains challenging, even when the calibration period exhibits excellent model performance. Furthermore, when considering model parameters and predicted streamflow uncertainty, it is advantageous to calibrate the hydrological model under dry climatic conditions to achieve more robust results.

Maastrichtian – Paleocene environmental and climatic conditions in Koum Basin (northern benue trough, Cameroon) inferred using a multiproxy approach including sedimentology, mineralogy, and geochemistry

The Koum Basin is one of major intracontinental basins in northern Cameroon. It is part of the Upper Benue Trough and has genetic ties to the West and Central African Rift System. The main purpose of studying the Koum Basin sedimentary deposits was to re-examine the time of the deposition and constrain the palaeoenvironmental and paleoclimatic conditions during deposition. To accomplish this, we used a combination of sedimentologic, palynologic, mineralogic, and geochemical data. Claystone units interbedded with calcareous siltstones dominate sedimentary sequence, including few clay beds, fine to medium-grained sandstone, and rare marl layers. The palynomorph assemblage suggests a previously unknown Maastrichtian – Paleocene age in this basin. The sediments originated from intermediate igneous parent rocks with a relative contribution of felsic rocks. These rocks underwent low detritism (Si/Al: 2.51–4.43; K/Al: 0.11–0.36; Ti/Al: 0.05–0.10) and chemical weathering (CIA: 55–64; PIA: 56–68) in the source region. Consequently, deposits are immature (ICV values > 1) and weakly recycled (Si2O3/Al2O3 ratios ≤5). The organic matter analysis and the palynoflora assemblage, reveal Type III kerogen with significant contributions of Type II-III and type II kerogens, as well as a continental paleo-depositional environment with open rainforest to savannah vegetation. The clay minerals distribution suggests moderate illitization and chloritization processes and thus moderate burial diagenesis at temperatures ranging from 70 to 90 °C, also attested by immature to mature Tmax values (≤436 °C) marginally. The low CIA values and very low kaolinite contents, indicate dry climatic conditions. In addition, two major-element-based discrimination diagrams show that the parent rocks of clastic sediments formed primarily in a continental arc system, with a moderate contribution from the rift system and a low contribution from the oceanic island arc, implying compressional conditions, which is consistent with previous studies on the tectonic background of the region during the late Maastrichtian to Paleocene period.

Impacts of record-breaking compound heatwave and drought events in 2022 China on vegetation growth

In the summer of 2022, China experienced a series of record-breaking heatwaves and unprecedented low rainfall-induced droughts across much of China's regions. Using a reanalysis of the meteorological dataset, we confirmed that the 2022 concurrent heatwaves in China were more frequent and widespread than in the past (1979–2021). The heatwaves presented the greatest record for heatwave count, heatwave days, and cumulative intensity, especially in the Yangtze River basin, Tibetan Plateau, and Northern China. Moreover, heatwaves often occur with concurrent droughts. We found heatwaves and droughts reduced vegetation growth over half of the vegetated areas in China, represented by the negative detrended anomalies of the Normalized Difference Vegetation Index (NDVI; 66.89 %), Enhanced Vegetation Index (EVI; 58.68 %), and contiguous solar-induced chlorophyll fluorescence (CSIF; 56.47 %). More importantly, nearly half of the land surface of China (48.28 %) in 2022 summer experienced warmer and drier climate conditions than in the historical period (1979–2021). As a result, 72.9 % of vegetation stress anomalies (i.e., negative detrended anomalies of vegetation indices) in those areas can be attributed to warmer and drier climate (20.3 %), individual extreme dry climate (2.0 %), individual extreme warm climate (43.1 %), and compound extreme events combining the driest and warmest conditions (7.5 %), respectively. These findings implied that heatwaves were more critical in limiting vegetation growth than drought this summer. Using a large ensemble model (i.e., CanESM5), we estimated the probability of exceeding the 2022 summer extreme daily maximum temperature (Tmax) in China and its subregions in the future climate. Generally, heat extremes greater than the observed record (i.e., 2022) are found in China every decade, with models indicating a likelihood of 0.42 % to 85.69 % from 2023–2032 to 2083–2092 in the SSP585 future scenario. Our study provides a timely and essential evaluation of the impacts of compound heatwaves and droughts on plant growth.

Water-use strategies and functional traits explain divergent linkages in physiological responses to simulated precipitation change

As a part of global climate change, precipitation patterns in arid regions will change significantly, and the different responses of desert plants to these changes will lead to alterations in community composition, thereby impacting ecosystem stability. Thus, understanding the mechanism underlying the associations among physiological response variables considering changing precipitation is crucial. Here, water-use strategies, functional traits, and physiological processes (e.g., photosynthesis (An), transpiration (Tr), leaf water potential (Ψl), stomatal conductance (gs), and soil respiration (Rs)) were measured in a precipitation experiment with two coexisting desert riparian species to determine how water-use strategies and functional traits operate together in generating physiological response mechanisms. The results showed that the two species exhibited divergent response pathways of physiological processes following rainfall events, although both were identified as isohydric plants with stringent stomatal regulation. For the shallow-rooted species N. sphaerocarpa, gs was sensitive to changes in both surface soil moisture (Swc) and Ψl, and Swc was the primary factor influencing Rs. These results were supported by the preference for shallow water and predominance of functional traits associated with drought avoidance. For the deep-rooted species R. soongorica, variations in gs were decoupled from Swc and directly influenced by enhanced Ψl, An was the main factor affecting Rs, while Ψl negatively affected Rs. These correlations could be attributed to the preference for deep water and functional traits associated with drought tolerance. These findings suggest that R. soongorica had a stronger tolerance to environmental water deficits and may expand extensively under drier climatic conditions in the future.

166 Pre-Weaned Calves Have Increased Cortisol Concentrations Post-Wildfire Smoke Exposure

Abstract The western states of the U.S., home to some of the largest cattle operations in the country, are increasingly experiencing losses related to wildfire events. Wildfires are predicted to intensify with climate change; rising temperatures, droughts, and drier climatic conditions. Although wildfires do not directly endanger most humans and animals, the resultant smoke can disperse great distances and increase disease susceptibility and death in populations removed from its origin. There is a lack of literature on how wildfire smoke exposure can affect livestock physiology, health, and productivity. Therefore, this study aimed to evaluate changes in blood markers of cattle naturally exposed to wildfire smoke. Eighteen beef-on-dairy calves (Jersey X Simmental) from a commercial farm were enrolled in this study at birth (May to June 2022). Blood samples for analysis of cortisol, acute phase proteins, and pro- and anti-inflammatory cytokines were collected before (June to August), during (September), and after smoke exposure (September and October), in a total of seven collections. Additionally, rectal temperature and health scores were collected from each calf at those time points. Air quality (AQ) data, specifically particulate matter (PM2.5; EPA standard for AQ; 35 µg/m3) near the study location (Vale, OR), was obtained from the AirNow database. For statistical analysis, calf was considered the experimental unit, and all data were analyzed using the MIXED procedure of SAS (SAS Inst. Inc., Cary, NC). Air quality before smoke exposure was considered adequate, and PM 2.5 was, on average, 4.9 µg/m3 from June to August. In September, a wildfire reduced AQ at the study location, increasing PM 2.5 to an average of 44.6 µg/m3 for four consecutive days. After the fire was contained, AQ improved, and PM2.5 dropped to 8.6 ug/m3. Blood cortisol concentrations changed over time (P < 0.001). Cortisol concentrations of samples collected before smoke exposure did not differ (P = 0.89) at 4.4, 2.0, and 1.9 ng/mL (SEM:1.3). Cortisol concentrations increased (P < 0.001) and peaked during smoke exposure, at 10.3 and 7.0 ng/mL (SEM:1.4). Immediately after smoke exposure, cortisol concentrations averaged 6.3 ng/mL, intermediate between those before and during smoke exposure (P = 0.89; SEM:1.3). Interestingly, in the last post-smoke exposure sample, cortisol concentration averaged 9.5 ng/mL, similar to concentrations during smoke exposure (P = 0.99; SEM:1.3). This increase in cortisol concentration post-smoke exposure was unexpected but likely explained by the calves having been weaned two days before this final sampling. In summary, calves naturally exposed to wildfire smoke had increased blood cortisol concentrations with concentrations similar to those observed shortly after post-weaning, a practice known to be challenging and stressful for calves.

The impact of paleoclimatic on the structural strength of loess paleosol sequences and its implications for tillage on the Loess Plateau: A case study from Luochuan profile

The structural strength of the Loess-Paleosol Sequence (LPS) and the presence of paleosols within the LPS have significant implications for tillage and understanding past climate conditions. This research investigation sought to examine the structural strengths of the Luochuan (LC) LPS via both triaxial shear and oedometer tests, with the microstructure being further characterized through scanning electron microscopy. Results indicate that the LPS's structural strength tends to increase as burial depth increases. Additionally, the loess layer's structural strength is typically lower than that of the adjacent paleosol layer. The LPS's microstructure experiences considerable transformations with increased burial depth, particularly regarding changes in particle contact relationship, degree of cementation, and pore volume. This shift is characterized by a transition from an overhead structure to a matrix structure. These findings suggest that the loess layers' structural strength is associated with weaker pedogenic weathering occurring under cold and dry climatic conditions, whereas the paleosol layer exhibits a higher structural strength due to intense weathering during a warm and humid climate. Overall, this study establishes a link between paleoclimate and mechanical properties, using microstructure as a mediating factor, and provides a theoretical basis for tillage on the Loess Plateau.

The late Quaternary palynological record of the northern Yangtze Delta: Implication for palaeoclimate change in East Asia

Marine Isotope Stage (MIS) 3 is the latest interstadial period with unstable climate regimes that provides an indispensable key to better predict future climate change. However, paleoclimate reconstruction in the Yangtze Delta covering MIS 3 remains elusive due to limited archives with reliable age. Here, we derived a 53,000–year–long paleoclimate record from the northern Yangtze Delta, using luminescence age–based palynological data of a coastal sediment core (YZ07). The results show that the climate was relatively warm and wet during ∼53.0–37.5 ka, followed by a slightly cool but wetter condition between ∼37.5 ka and ∼33.2 ka. Afterwards, a cool and dry climate prevailed from ∼33.2 ka to ∼30.7 ka. Three cold events were identified around 48.0 ka, 39.0 ka and 31.0 ka, corresponding to the timings of Heinrich Event (HE 5), HE 4 and HE 3, respectively. From ∼30.7 ka to ∼11.5 ka, broadleaved forests and wetland herbs obviously contracted in the Yangtze Delta region, indicating cold and dry climate conditions. From the late Pleistocene to Holocene, the pollen variations in this core site were linked to coastal geomorphology under climate–induced sea–level changes. Besides, our findings suggest that the percentages of emergent vegetation in this work were negatively correlated with El Niño–Southern Oscillation (ENSO)–linked flood events during the Holocene. Overall, from mid–MIS 3 to MIS 2, the climate exhibits a ‘warm–cool–cold’ pattern in the Yangtze Delta, broadly concordant with other climate proxies in East Asian monsoon domain and beyond on suborbital or millennial timescales. We argue that the northern hemisphere summer insolation may be responsible for the paleoclimate variability and paleovegetation successions in the Yangtze Delta. However, the variability of precipitation in MIS 3 might be governed by interhemispheric insolation forcing, which accounts for a wetter climate phase occurring during late MIS 3 rather than mid–MIS 3.

Moniliformin Occurrence in Serbian Maize over Four Years: Understanding Weather-Dependent Variability.

Moniliformin (MON) represents one of the most widespread emerging mycotoxins, whose presence in food and feed can potentially cause harmful effects on the health of both the public and animals. In order to investigate MON occurrence, a total of four hundred (n = 400) samples of unprocessed maize were sampled from different regions (Bačka, Banat, and Srem) of Serbia during a period of four years (2018-2021) and were analyzed using a validated liquid chromatography with tandem mass spectrometry (LC-MS/MS) method. The influence of regional differences and variations from year to year in terms of weather conditions on the occurrence of MON was also assessed. The obtained validation parameters indicated that the LC-MS/MS method is applicable to the determination of MON in maize samples. It can be observed from the acquired findings that all samples were contaminated with MON, while concentration levels varied between the samples, especially from different sampling years. The maize samples showed the greatest levels of MON concentration during the dry and hot climatic conditions experienced in 2021. In maize samples harvested in the period 2018-2020, the MON concentration levels detected were about two to three times lower compared to the year 2021. Additionally, a comprehensive investigation into the correlation between weather conditions and the occurrence of MON in maize grown in Serbia was undertaken by reviewing the outcomes of research undertaken in the past decade.

The competitive effect of neighbouring plants on the growth of two eucalypts is stronger in dry conditions

Abstract Plant growth is influenced by interactions with neighbouring plants. The strength and direction of the cumulative neighbourhood effect on growth can depend on neighbour properties, such as their abundance, size and proximity, as well as the degree of similarity between interacting plants and their traits, which can be captured by the species identity of neighbours. Such interactions are also influenced by the local environmental conditions that are largely determined by climate. Because neighbour and climatic effects are typically explored in isolation, particularly in long‐lived species such as trees, it is unclear how the impacts of neighbours on plant growth shift in response to temporal variation in climatic conditions. Here, we explored how neighbouring plants impact the annual growth of two eucalypts, Eucalyptus delegatensis and Eucalyptus regnans, over three growing seasons in an experimental forest in south‐east Tasmania, Australia. We assessed whether eucalypt growth rates could be described by the number, size, proximity, and species identity of neighbours, and how the strength of this effect was influenced by the growing season climatic conditions. We found that climate and neighbouring plants had an interactive impact on eucalypt growth. Neighbours had a consistent, competitive effect on the growth of both eucalypts in all three growing seasons which was strongly related to the cumulative neighbourhood biomass. The identity of neighbours was important in determining E. regnans growth only, whereby distinguishing neighbours according to functional group best described growth. Over all three growing seasons, we predicted that, on average, neighbours reduced E. delegatensis and E. regnans mean annual growth by 60.5% and 48.4%, respectively. However, the strength of the competitive effect of neighbours on eucalypt growth was related to growing season climate, being strongest when conditions were hot and dry and weakest in cool, wet conditions. Synthesis: Given the consistent results observed in two co‐occurring eucalypts, our findings suggest that drier and hotter climatic conditions increase the strength of competitive effects on tree growth. This has implications for future forest productivity given projected increased temperatures and variation in rainfall patterns globally.

Chronic warming and dry soils limit carbon uptake and growth despite a longer growing season in beech and oak.

Progressively warmer and drier climatic conditions impact tree phenology and carbon cycling with large consequences for forest carbon balance. However, it remains unclear how individual impacts of warming and drier soils differ from their combined effects and how species interactions modulate tree responses. Using mesocosms, we assessed the multiyear impact of continuous air warming and lower soil moisture alone or in combination on phenology, leaf-level photosynthesis, nonstructural carbohydrate concentrations, and aboveground growth of young European beech (Fagus sylvatica L.) and Downy oak (Quercus pubescens Willd.) trees. We further tested how species interactions (in monocultures and in mixtures) modulated these effects. Warming prolonged the growing season of both species but reduced growth in oak. In contrast, lower moisture did not impact phenology but reduced carbon assimilation and growth in both species. Combined impacts of warming and drier soils did not differ from their single effects. Under warmer and drier conditions, performances of both species were enhanced in mixtures compared to monocultures. Our work revealed that higher temperature and lower soil moisture have contrasting impacts on phenology vs. leaf-level assimilation and growth, with the former being driven by temperature and the latter by moisture. Furthermore, we showed a compensation in the negative impacts of chronic heat and drought by tree species interactions.

Fossil energy reduction for heating and cooling of buildings using shallow geothermal integrated energy systems – a comprehensive review

Ground source heat pumps (GSHP) are a very efficient system for space heating and cooling, and it was established in 1904. GSHPs can minimize the environmental effect of buildings by using the ground as a renewable energy source. The ground will act as a heat sink or heat source. The research collection aims at finding the various possible opportunities for the effec-tive integration of shallow geothermal energy (SGE) to decrease the fossil energy in the built environment and to reduce emission associated with it. The direct utilization of SGE using a ground source heat pump (GSHP) has been reviewed in detail for global north and global south countries, with a primary focus on heating application. The punctual information of results of various authors have been extensively summarized. This review discusses the GSHP installation status, SGE availability, GSHP system simulation, feasibilities, and performance. Worldwide more than one million GSHP systems have been installed, and the system is prev-alent in Europe, the Americas, and Asia. Most of the systems are installed for heating-domi-nated buildings in the global north. This paper also contains the research details pertaining to the last two decades about refrigerants and compressors for the development of GSHP. Finally, the feasibility study and the performance of the GSHP unit for different climatic conditions are reviewed and it is found that the technique is more feasible for cold and dry climatic con-ditions. This paper highlights the recent research findings and a potential gap in the above components for further research and development.