Water Availability Research Articles

Residual Nitrite, Nitrate, and Volatile N-Nitrosamines in Organic and Conventional Ham and Salami Products.

Nitrite and nitrate in meat products may be perceived negatively by consumers. These compounds can react to form carcinogenic volatile N-nitrosamines. "Nitrite-free" (i.e., uncured) organic meat products may contain nitrate from natural sources (e.g., spices and water). We studied the quality of ham and salami (conventional cured; organic cured; organic uncured). Residual nitrite and nitrate, volatile N-nitrosamines, microbial load, surface color, water activity, and pH were determined, considering one week of refrigerated storage in open or unopened packages. Residual nitrite and nitrate in organic, uncured salami were similar to cured salami, presumably from the addition of herbs and spices and nitrate reduction by nitrate reductase from microorganisms. For cooked ham, residual nitrite was significantly lower in the organic, uncured sample, while residual nitrate was not detected. N-nitrosodiphenylamine was detected in all samples at day 0, exceeding, in three out of five cured and both uncured products, the US legal limit of 10 µg/kg of volatile N-nitrosamines in foods. This finding warrants further investigation. The microbial load in salami products was dominated by bacteria from starter cultures. In ham, a slight increase in total aerobic count and lactic acid bacteria during storage was noted. Overall, the microbial quality of the products was as expected for the respective product types.

Assessment of natural radioactivity levels in polychaetes along southeast coast of Chennai, Tamil Nadu, India – a pilot study

The current findings intended to assess the concentrations of natural radioactivity in water, sediment, and polychaete worms Marphysa madrasi and Namalycastis jaya in 12 distinct places along the southeast coast, of Chennai, Tamil Nadu, India. Mean gross alpha and beta activity in water samples from 12 locations ranged 0.43 ± 0.02 mBq/L and 1.65 ± 0.12 mBq/L, respectively. Similarly, for sediment samples, the average activity concentration for gross alpha and beta were 196.67 ± 0.23 and 1190. ± 0.34 Bq/Kg, respectively. The net radioactivity (gross alpha and gross beta) in Marphysa madrasi ranged 32.97 ± 0.13 & 528.24 ± 0.32 Bq/Kg, respectively and in Namalycastis jaya, the gross alpha activity’s average ranged 29.07 ± 0.20 Bq/Kg and a gross beta activity average of 280.36 ± 0.23 Bq/Kg. According to the findings, the highest radiation levels were found in Nemilli (S7) for polychaetes. The least radiation levels in polychaetes were found in Pattinapakkam (S3) and Muttukaadu (S6) for Marphysa madrasi and Neelankarai (S4) for Namalycastis jaya. Conversely, across all 12 selected sites, the gross beta activity of water, sediment, and polychaete worms is greater than the gross alpha activity.

Molecular simulation on Cs, Rb retention in Na/K-montmorillonite interlayer coupling clay swelling/collapse

A key issue about radioactive waste disposal and nuclear accident contamination control is the retention of radionuclides in clay minerals. The cation (Cs+, Rb+, Na+, K+) selectivity in montmorillonite (Mt) interlayers have not been quantitatively studied. This work employs classical molecular dynamics (CMD) to systematically investigate the interlayer structure, swelling properties, diffusion dynamics, and cation exchange processes. The selectivity of alkali ions within the interlayer space coupled with clay swelling/collapse under different water activity (aw) and cation activity, has been quantified. Both Cs-, Rb-Mt demonstrate a monolayer hydrate configuration as the most stable state. The mobility of intercalated species, as indicated by self-diffusion coefficients, exhibits a stepwise trend with increasing water content. The cationic selectivity within the interlayer follows the order Cs+ > Rb+ > K+ > Na+ at aw = 1.0. The logarithm values of the selectivity coefficients for Cs/Rb relative to Na/K are as follows: logKc(Cs/K) = 0.73, logKc(Cs/Na) = 1.62, logKc(Rb/K) = 0.62, and logKc(Rb/Na) = 1.57 at aw = 1.0. A model correlating selectivity coefficients with water activity has been proposed. It is noted that Cs+ and Rb+ ions tend to accumulate within the interlayer as water activity decreases, and interlayer Rb+ competes with Cs+ for exchange positions at low water activity. These results can be used to quantify cationic partitioning during the remediation of radiocesium contamination in soil and weathering processes of sediments.

Environmental DNA Reveals Habitat Variables Driving Platypus (Ornithorhynchus anatinus) Distribution Across an Urbanised Landscape.

Freshwater waterways, and species that depend on them, are threatened by urbanisation and the consequences of the urban stream syndrome. In south-east Queensland, Australia, little is known about the impacts of the urban stream syndrome on the platypus (Ornithorhynchus anatinus), meaning that populations cannot be adequately managed by conservation practitioners. The aim of this study was to determine how habitat and environmental variables, related to the urban stream syndrome, influenced platypus distribution across this region. We used environmental DNA sampling over a 5-year period (2016-2020) to determine how platypus occurrence (presence or absence) was affected by habitat and the environment. Five scenarios based on key characteristics of the urban stream syndrome were modelled using binomial generalised linear models. The highest-ranked model of platypus occurrence included positive effects of topographic wetness index and coarse organic matter. These findings reflect important waterway connectivity and food resources for platypus, highlighting relationships between platypus, their environment and their tolerance to urban stream threats. For example, platypuses are unlikely to occur in streams where water availability is reduced, and movement will be limited in shallow, dry streams. Therefore, waterway management should focus on water availability and connectivity, especially during drought. Our study can be used to guide management plans for the persistence of platypus and other freshwater species.

Solar-Driven Plasmon-Enhanced Photocatalysis: Co2+-doped ZnFe2O4 Nanospheres embedded ZnO Nanosheets for Effective Degradation of Dyes and Antibiotics

To ensure sustainable management and availability of water and sanitation for all, a UN Sustainable Development Goals(SDGs) promising methods to eliminate aqueous pollutants is urgently required. Solar-photocatalysis, driven by freely...

Spawn-based pellets of Pleurotus ostreatus as an applied approach for the production of laccase in different types of water.

In recent years, oxidoreductase enzymes such as laccases have received considerable attention for their ability to degrade and eliminate organic micropollutants from contaminated water in a process known as enzyme-based wastewater treatment. Thus, methods to produce high laccase activity in water are a point of focus, with white-rot fungi being highlighted as a tool in this context. This study, therefore, explored the applied approach of direct addition of mushroom spawn of the white-rot fungi Pleurotus ostreatus into water and its potential for laccase production under different conditions. Grain spawn was observed to be preferable to sawdust spawn, resulting in laccase activity of 53.9±5.9U/L and 4.8±0.8U/L, respectively. Laccase activity was induced by adding kraft lignin (4g/L), and an eightfold increase to 446.3±43.1U/L was observed for grain spawn. Lignin accumulated in the spawn over time, resulting in brown pellets composed of spawn, mycelium and lignin. Our results demonstrated that high levels of laccase activity could be obtained in different types of water, including effluent municipal wastewater, using this method. No impact from the addition of inorganic nitrogen (ammonium nitrate, N-levels 14mg/L, 140mg/L) or organic nitrogen sources (urea, yeast extract, wheat bran, N-levels 14mg/L, 140mg/L) was observed for the treatment with grain spawn and lignin, suggesting that stable laccase activity can be expected under these nutritional conditions.

Site Suitability Analysis for Green Hydrogen Production Using Multi-Criteria Decision-Making Methods: A Case Study in The State of Ceará, Brazil

– Brazil is leveraging its extensive potential in solar, wind, and hydro energy to establish itself on the global map of green hydrogen production—a pivotal component in the ongoing energy transition. The economic viability of green hydrogen hinges on optimal locations with abundant renewable resources, space for solar or wind farms, access to water, and the potential for exporting to major demand centers. In this context, this study evaluates the potential for green hydrogen production in the State of Ceará, Brazil, using multi-criteria decision-making (MCDM) methods, which are designed to prioritize conflicting tangible and intangible criteria to determine the best decision alternatives. The additive ratio assessment (ARAS), simple additive weighting (SAW), combinative distance-based assessment (CODAS), and technique for order performance by similarity to ideal solution (TOPSIS) methods are evaluated for decision-making purposes, with weighting and aggregation relying on the best-worst method (BWM) and ensemble ranking. Criteria considered in the analysis include suitable areas for wind and solar farms, wind and solar energy potentials, water availability, surface temperature, electrical infrastructure, population, and local gross domestic product (GDP). The municipalities with the highest potential for renewable hydrogen production identified are Tauá (638 kton/year), Araripe (471 kton/year), and Beberibe (462 kton/year). According to the results, Araripe emerges as the most suitable municipality for green hydrogen production in Ceará.

Chickpea displays a temporal growth response to Mesorhizobium strains under well-watered and drought conditions.

The relative performance of rhizobial strains could depend on their resource allocation, environmental conditions, and host genotype. Here, we used a high-throughput shoot phenotyping to investigate the effects of Mesorhizobium strain on the growth dynamics, nodulation and bacteroid traits with four chickpea (Cicer arietinum) varieties grown under different water regimes in an experiment including four nitrogen sources (two Mesorhizobium strains, and two uninoculated controls: nitrogen fertilised and unfertilised) under well-watered and drought conditions. We asked three questions. Does the impact of rhizobial strains on chickpea growth change with well-watered versus drought conditions? Do Mesorhizobium strains differ in their ability to influence biomass and nodule traits of chickpea varieties under well-watered and drought conditions? Are bacteroid size and amount of polyhydroxybutyrate modified by Mesorhizobium strain, chickpea variety, water availability and their interactions? Under well-watered conditions, chickpea inoculated with CC1192 showed higher shoot growth rates than M075 and accumulated high plant biomass at harvest. Under drought conditions, however, the shoot growth rate was comparable between CC1192 and M075, with no significant difference in plant biomass and symbiotic effectiveness at harvest. Across sources of variation, plant biomass varied 3.0-fold, nodules per plant 3.9-fold, nodule dry weight 3.0-fold, symbiotic effectiveness 1.5-fold, bacteroid size 1.4-fold and bacteroid polyhydroxybutyrate 1.4-fold. Plant biomass was negatively correlated with both bacteroid size and allocation to polyhydroxybutyrate under well-watered conditions, suggesting a trade-off between plant and rhizobial fitness. This study demonstrates the need to reassess rhizobial strain effectiveness across diverse environments, recognising the dynamic nature of their interaction with host plants.

Potencial da cinza vegetal nas características produtivas de amendoim e mitigação do déficit hídrico

ABSTRACT The application of wood ash in agriculture emerges as a promising technique to enhance agricultural productivity. Its chemical composition can improve soil attributes, acting as a fertilizer, corrective agent, and assisting in water retention. However, studies recommend controlled adoption to avoid adverse impacts. The objective of this article is to evaluate the potential of wood ash as a fertilization strategy in peanut cultivation, with an emphasis on optimizing plant productivity and reducing water deficit. The experiment was carried out in a greenhouse in 5 dm3 pots; the experimental design applied was randomized blocks, forming a 5x5 factorial scheme, corresponding to five doses of wood ash (0; 8; 16; 24 and 32 g dm-3) and five levels of water availability (25; 50; 75; 100 and 125% of field capacity), with four repetitions. The cultivar used was IAC OL-3. The data were subjected to the normality test to check whether they followed the normal distribution and, subsequently, subjected to analysis of variance and, when significant, subjected to regression analysis, at a 5% probability of error. Wood ash, rich in nutrients, proved to be a viable alternative source of nutrients. Doses between 18.4 and 22.8 g dm-3 of wood ash led to the most satisfactory results. The water availability that responded best ranged from 96 to 111.3%. Wood ash, at doses of 22.8 and 19.64 g dm-3, contributed to water consumption and soil water efficiency.

Waterborne contaminants in high intensity agriculture and plant production: A review of on-site and downstream impacts.

Waterborne contaminants pose a significant risk to water quality and plant health in agricultural systems. This is particularly the case for relatively small-scale but intensive agricultural operations such as plant production nurseries that often rely on recycled irrigation water. The increasing global demand for plants requires improved water quality and more certainty around water availability, which may be difficult to predict and deliver due to variable and changing climate regimes. Production nurseries are moving to adopt best management practices that recycle water; however, the risks associated with waterborne contaminants of various types, including nutrients, pesticides, plant pathogens, micro-plastics, and toxic metals, are not well understood. We review and synthesise the physical and biogeochemical factors that contribute to waterborne contaminant risk, and the main types of contaminants that are likely to require management, at plant production nurseries. Catchment characteristics (i.e., topography, land use), hydroclimatic factors (i.e., storms, floods, droughts), and landscape hydrological and sediment connectivity influence surface runoff, sediment transport, and associated contaminant transfer and storage. High hydrological connectivity can increase the risk of contaminant transport from the surrounding landscape to nurseries, with potential negative impacts to water quality in reservoirs and in turn plant health. High connectivity may also increase the risk of contaminants (e.g., sediment, pesticides, and phytopathogens) being transferred from nursery farms into downstream waterways, with consequences for aquatic ecosystems. Like all intensive agricultural operations, nurseries need to consider sources of irrigation water, water treatment and management strategies, and catchment and hydroclimatic factors, to mitigate the spread of contaminants and reduce their impacts on both plant production and the surrounding environment. Further research is needed to quantify contaminant loads and transfer pathways in these agricultural systems, and to better understand the threshold levels of contaminants that adversely affect plant health and which may result in devastating economic losses.

Water availability, water content and chemical treatment of seeds on the emergence of soybean seedlings

Water availability, water content and chemical treatment of seeds on the emergence of soybean seedlings

Drying Characteristics, Color, and Functional and Chemical Properties of Figl (Raphanus sativus L.) Leaves and Petioles Under Convective Drying Conditions

Investigating the effect of drying temperature on the quality of the leaf and petiole parts of Figl is essential to use the leaf and petiole for food formulation or as food ingredients in developing countries to overcome the problem of food security. In this study, the effect of drying temperature (27.20°C ± 2.1°Cor in the sun, 40°C, 50°C, and 60°C) on drying rate, moisture diffusivity, color, and functional and chemical properties of the leaf and petiole was investigated. A two‐way analysis of variance was performed using a Statistical Analysis System to evaluate the effect of drying temperature on the drying characteristics, color, and chemical and functional properties of the leaves and petioles of Figl. The effective diffusivity values changed from 4 × 10−12 to 8.2 × 10−12 m2/s and 2.1 × 10−08 to 4.9 × 10−8 m2/s for the leaf and petiole of Figl, respectively, within the given temperature range. The bulk densities of the leaf and petiole of Figl were in the range of 0.20–0.35 g/mL and 0.27–0.41 g/mL, respectively. The results indicated that drying rate, moisture diffusivity, water activity, ascorbic acids, and delta decreased with drying temperature, whereas the functional properties of both the leaf and petiole increased with drying temperature. Comparatively, the petiole part showed better results in terms of functional and chemical properties than the leaf at all drying temperatures. From the results of the study, in terms of functional and chemical properties, drying of the petiole at 50°C for 120 min was found to be the optimum temperature for better quality.

Microbiological and Physicochemical Characterization During Biodrying of Organic Solid Waste

The correct management of high-moisture organic waste (HMOW) is crucial to minimize its environmental impact and take advantage of its potential as a valuable resource, thus linking it to the circular economy, sustainable production and recycling. Processes such as anaerobic digestion, composting and, more recently, biodrying have been applied to support the sustainable management of HMOW. However, the latter has not yet been well characterized, so this study focuses on elucidating the behavior of microbial populations and their relationship with physical and chemical conditions during biodrying. In a greenhouse, a semi-static pile with an initial water content of 88%, composed of orange peel waste (80%), sugarcane bagasse (16.5%) and mulch (3.5%) was biodried for 50 days. Biodrying went through three stages: (1) the mesophilic stage, when different microbial populations decompose some organic matter, causing a temperature increase from 25 to 40 °C; (2) the thermophilic stage, in which the highest microbial counts were found, most of which corresponded to the highest temperatures reached and maintained between 40 and 62 °C, and, consequently, to the greatest decrease in water content (from 78 to 41%); and (3) the cooling phase, when the temperature dropped to 23–25 °C. The aeration and mainly the microbial activity were responsible for most of the water evaporation. Microbial activity in biodrying of HMOW ended on day 32, when the humidity was lower than 30% and the water activity (aw) was below 0.8. After that, moisture loss was carried out only by convection and radiation. Obtained biodried organic waste (10% water-content) could be used as an alternative fuel in many industries.

Performance evaluation of indirect solar drying system for potato slices: Comparative analysis with open-sun drying method

In this study, a partially portable indirect solar dryer (ISD) was constructed and potato slice drying characteristics were analyzed compared to the open-sun drying (OSD) method. Potato slice samples were prepared and the experiment was carried out for two days. Weight reduction environment temperature, collector plate temperature, drying chamber temperature, and drying chamber inlet temperature were recorded from 10 AM to 6 PM. every 30 min to analyze various drying characteristics. Initially moisture content (MC) of the potato slices was 83 ± 2 % (wb); after drying the final MC was 11.7 ± 2 % (wb) for OSD and 7.7 ± 2.0 % (wb) for ISD system, both in 16 h. The highest drying rate (DR) of potato slices was 18.8 (g water/g solid h) after 8 h of open sun drying, and 16.97 (g water/g solid h after) 8 h. Rehydration ratios for OSD and ISD were found 4.32 and 4.20, respectively. Shrinkage factor for OSD was 61 %, whereas ISD had a shrinkage ratio of 70 %. The highest color change values were 6.32 and 8.13 in the ISD and OSD, respectively. Water activity was reduced from 0.95 to 0.42 in ISD and from 0.95 to 0.59 in OSD.

Microbial Quality and Production Methods of Traditional Fermented Cheeses in Lebanon.

This study is aimed at evaluating the quality and safety of two traditional fermented dairy products commonly found in Lebanon (Ambarees and Kishk in its dry and wet forms) by detecting foodborne pathogens and indicator microorganisms. Additionally, it seeks to identify the strengths, weaknesses, opportunities, and threats to quality and the production level. A total of 58 random samples (duplicated) including goat milk (n = 16), dry Kishk (n = 8), wet Kishk (n = 8), and Ambarees (n = 26) were collected from individuals who both farm and process these products. They represent the two production levels within the identified value chains in the Shouf and West Bekaa regions. Microbiological analyses revealed that all samples were free of Escherichia coli, while Staphylococcus aureus was found in all of them with significantly higher levels of contamination in wet Kishk, indicating poor hygienic practices at the different production levels. Coliforms were found in only 3.8% of the Ambarees samples, made from raw milk, showing that the decreasing pH and water activity throughout the long milk fermentation process contributes to the low prevalence of these microorganisms and that cross-contamination might have occurred during the packaging phase. A regional pattern was observed where microbial counts (total aerobic counts, total coliforms, and S. aureus) were found significantly higher (p < 0.05) in milk samples of the West Bekaa, suggesting better hygienic conditions in the Shouf as compared to the West Bekaa. This analysis would be an important tool for developing the goat dairy sector and enhancing the production and promotion of traditional goat milk products. Valorization at the different levels of the value chain, starting with the adoption of good production practices on the farm, training on hygienic standards, innovation in packaging and marketing, and developing adequate policies, may ensure high-quality end-products that will eventually contribute to the livelihoods of the main stakeholders in this value chain and help preserve these national culinary gems.

Yam starch-based sustainable edible films loaded with bioactive components from aroeira leaf extract: Mechanical, physical, and antioxidant properties.

This study aimed to investigate the impact of adding aroeira leaf extract (Schinus terebinthifolius Raddi) to a yam starch film matrix, focusing on the development of potentially active films and the evaluation of their physicochemical, mechanical, optical, and antioxidant properties. Films were produced using the casting method with varying extract concentrations (0, 3, 6, 12, and 15 %), yam starch (2 %), and glycerol (1 %). The antioxidant properties were analyzed by determining the total phenolic content, 2,2-Diphenyl-1-Picrylhydrazyl (DPPH) radical scavenging, ferric reducing power, and 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical elimination, which revealed a significant increase in antioxidant properties as the extract concentration increased. The incorporation of the extract resulted in increased film thickness and decreased solubility, water activity, and moisture, as well as changes in brightness (L*), tensile strength, and elongation. X-ray diffraction (XRD) showed an increase in the crystallinity of the films, whereas Fourier-transform infrared (FTIR) analysis revealed similar spectra among the films. The thermal stability did not exhibit significant variations with the addition of the extract, indicating high heat resistance. Films with 15 % extract showed changes in the surface microstructure, indicating greater roughness than the control film. Thus, formulations with 3 %, 6 %, and 9 % aroeira extract emerged as the most promising, suggesting their potential for application in active packaging and as a sustainable alternative for food preservation.

Simultaneous Application of Electron Beam Irradiation and Freezing as an Effective Method for Shelf Life Extension of Minced Turkey Meat.

In this study, minced turkey meat samples were subjected to electron-beam irradiation with dosages of 0, 1.5, 3, and 5 kGy, and then microbial (mesophilic and psychrotrophic bacteria), physiochemical (pH, water activity [aw], thiobarbituric acid reactive substances [TBARS], and peroxide value [PV]), and sensory (color, odor, texture, and overall acceptability) analyses were performed at 0 and 6 months of freezing storage (-18°C). Results showed that by 5 kGy irradiation and freezing treatments, the counts of psychrotrophic and mesophilic bacteria reduced remarkably (p < 0.05) and reached from 4.44 to 2.05 and from 4.9 to 2.00 log cfu/g, respectively. pH and aw of samples did not change notably after treatment and 6 months of freezing storage, the pH and aw of the minced turkey meat were 5.74 and 0.95 for 5 kGy irradiated samples, respectively. Despite the increase of TBARS and PV values, electron-beam irradiation at 1.5 and 3 kGy had no notable impact on the sensory characteristics of minced turkey meat. The obtained findings revealed that the simultaneous use of irradiation and freezing is a promising method for the increase of shelf life and preservation of minced turkey meat quality.

Drying Methods of Duck Blood: Changes in Volatile Components and Physicochemical Properties

This study investigated the physicochemical properties and volatile components of duck blood powder to determine its quality characteristics based on drying methods. The drying methods of duck blood samples used were freeze drying (FD), hot air drying (HD), spray drying (SD), and vacuum drying (VD). Duck blood powder treated with HD presented the lowest lightness and the highest carbonyl content. The VD-treated powder exhibited the highest water activity and redness. The composition of volatile compounds in duck blood varied based on the drying method, with VD presenting the highest total relative concentration but the least number of identified compounds. The most abundant compound was d-limonene, which was found in all the samples, followed by hexanal in VD and SD, p-xylene in FD, and trimethylamine in HD. Principal component analysis and heatmap analysis demonstrated that duck blood samples processed using different drying methods exhibited distinct volatile compound profiles, with HD, FD, SD, and VD samples associated with specific chemical groups. Multiple factor analysis revealed distinct correlations between drying methods and the physicochemical properties of duck blood, with VD samples showing higher water activity, aldehydes, and ketones, whereas HD samples exhibited increased carbonyl content and acids, highlighting the influence of heat on protein oxidation. VD method, therefore, presents excellent characteristics in terms of time and quality during the powdering process to increase the industrial utilization of duck blood. These findings provide valuable insights for the food industry, enabling the selection of appropriate drying methods that preserve the desired qualities of duck blood, thereby enhancing its commercial viability and potential application in a variety of food products.

Water scarcity: A global hindrance to sustainable development and agricultural production – A critical review of the impacts and adaptation strategies

Abstract Water is essential for sustaining life and required for carrying out basic daily activities. Even though water covers the vast majority of the earth’s surface, the availability of fresh water, which is necessary to maintain human activities, is limited, making it a scarce resource. Climate change, overexploitation of groundwater, and population growth are all putting significant pressure on natural water sources, which pose a serious threat to various sectors of society, especially in agriculture. Future projections of freshwater availability indicate agriculture production will suffer a significant shock globally, including in India, leading to a threat to food security and sustainability. To ensure the sustainability of this vital resource, it is crucial to use water sensibly. Moreover, it is essential to adopt certain strategies to manage agricultural water use effectively. This includes adopting various water-efficient techniques such as ‘micro-irrigation’, ‘irrigation scheduling’, ‘conservation agriculture’, ‘crop switching’ and so on. In this review, firstly, we discuss water scarcity and its types, causes, crisis for water shortages and hindrance to sustainable development from a global perspective emphasizing the Indian scenario as a developing nation. Secondly, we elaborated our discussion on water scarcity in agriculture including the impacts of water scarcity on agricultural production and its connection to climate change, population growth, and overexploitation of natural resources globally focusing on the Indian scenario. In addition, innovative water management practices and adaptation strategies to manage agricultural water use, constraints, and the need for further research are also covered. It is anticipated that this review will benefit researchers and policymakers by providing useful information on the impacts of water limitation and adoption strategies.

Multiple Elevation‐Dependent Climate Signals From Quantitative Wood Anatomical Measurements of Rocky Mountain Bristlecone Pine

AbstractSouthwestern North America has experienced significant temperature increases over the last century, leading to intensified droughts that significantly affect montane forests. Although tree‐ring data have provided long‐term context for this recent drought severity, the varying physiological responses of trees to climate variability make it challenging to disentangle the combined influence of temperature and soil moisture. Here we investigate complex climate‐growth relationships in Rocky Mountain bristlecone pine (Pinus aristata) at a low‐elevation and a high‐elevation site using quantitative wood anatomy (QWA). Significant correlations with climate were found for low‐elevation tree‐ring width (TRW) and earlywood chronologies, including positive correlations with spring and early summer precipitation and drought indices and negative correlations with spring and early summer maximum temperatures. At high elevations, TRW and earlywood chronologies show positive responses to summer moisture, whereas latewood chronologies correlate positively with August and September maximum temperatures and negatively with August precipitation. We leverage this differing seasonality of moisture and temperature signals and compare the QWA data to known droughts. The earlywood lumen area is found to be highly responsive to drought because of its physiological reliance on water availability for maintaining turgor pressure during cell enlargement. We also observed a decline in temperature sensitivity at the high elevation site, suggesting shifts in the dominance of limiting factors. Integrating QWA with traditional dendrochronology improves interpretations of tree‐ring data for use in climate reconstruction, offering detailed insights into tree physiological responses and the mix of environmental and developmental controls on cell growth.