Reduced Water Availability Research Articles

Fallowing Strategy and Its Impact on Surface Water and Groundwater Withdrawal, and Agricultural Economics: A System Dynamics Approach in Southern New Mexico

Enhancing the comprehension of alterations in land use holds paramount importance for water management in semi-arid regions due to its effects on hydrology and agricultural economics. Allowing agricultural land to lie fallow has emerged as a technique to decrease water use. This research employs the methodology of system dynamics modeling to evaluate the hydrologic and agricultural economic ramifications of employing the fallowing strategy, which aims to preserve water resources in interconnected socio-hydrologic systems. This strategy is explored across three different crops, focusing on the Mesilla–Rincon Valley (MRV) in southern New Mexico. The study’s timeline spans from 2022 to 2050 with historical background from 1969 and encompasses various dimensions, including water availability, land utilization, and agricultural economics. Three types of crops were selected for the fallowing strategy, including cotton, alfalfa/hay, and chile. For each crop, 2500 acres of it would be designated for fallowing separately in two subsequent years, allowing the land to be cultivated in the third year and recurring such pattern. Simulation findings across scenarios (GFDL, UKMO, and NCAR) indicate that water withdrawals for all crops decreased significantly, ranging from approximately 2.69% to 4.37%. Similarly, agriculture income experienced reductions, varying from around 1.53% to 2.26%. Also, surface water and groundwater withdrawals are represented as percentages. The data illustrate significant reductions in water withdrawals across all scenarios. For instance, in the GFDL scenario, surface water withdrawal decreased by approximately 1.85% for cotton, 2.56% for alfalfa/hay, and 1.58% for chile. Similarly, groundwater withdrawals saw substantial reductions, such as 14.93% for cotton, 20.44% for alfalfa/hay, and 12.62% for chile. These numbers emphasize the urgent need for sustainable water management practices to address the challenges posed by reduced water availability.

Economic and financial consequences of water risks: The case of hydropower

Reduced water availability poses risks for many economic activities. This paper studies how water risks affect hydroelectricity generation in Europe and the US and whether these risks are priced in by financial markets. To this end, we build a novel dataset for the period 2015–2022, which combines plant-specific hydroelectricity generation with geo-specific water physical risks and equity returns. We find that water risks, measured using model-based aggregate water risk metrics as well as precipitation anomalies, are significantly associated with reduced electricity generation, although the effect disappears after two months. We then link the power plants in our sample to the equity returns of their owners to investigate whether financial markets adequately price water risks. Using a portfolio sorts approach, we find weak evidence of a negative risk premium. Given the real negative effect of water risks on generation, we conclude that the lack of a positive risk premium amounts to mispricing of water risks by financial markets.

Assessment of mutant rice genotypes on growth cycle length and response to reduced water availability

Assessment of mutant rice genotypes on growth cycle length and response to reduced water availability

COBERTURA VEGETAL, AÇÃO ANTROPOGÊNICA E PALEOCLIMAS NA CAATINGA

The Caatinga is dominated by a semiarid climate and a high plant biodiversity dealing with anthropogenic disturbance and climate change. Previous studies suggest that Caatinga became a completely soil‐water pulse-dominated forest in response to reduced water availability at the end of the last ice age, around 10 cal kyr BP. This work aimed to identify vegetative and climatic evolution, and the human influence in the Cariri region, one of the driest parts of Brazil. We sampled soil in a temporal pond to identify pollen. The testimony is 170 cm in lenght and achieves 6,216 cal yr BP at the base. Pollen analysis indicates the presence of taxa representative of humid climates, between 6,216 and ca. 5000 cal yr BP, like Azolla, followed by implantation of Caatinga's modern configuration from ca. 4,900 cal yrs BP. After 2,700 cal yr BP, humid episodes occurred, possibly related to the El Niño - La Niña variation across the region, marked by increased algae and aquatic herbs concentrations. The occurrence of human activity species like Caryocar, Dioscorea, Spondias, and Licania suggest possibly landscape manipulation by pre – Columbian populations, and exotic Pinus and Prosopis reveal changes in the tree cover caused by European colonization in the Caatinga. Keywords: Anthropocene; Dry Forest; Paleogeography; Semiarid Region; Sedimentology, Lakes, Lagoons & Swamps.

Trade-off in the partitioning of recent photosynthate carbon under global change.

There may be trade-offs in the allocation patterns of recent photosynthetic carbon (RPC) allocation in response to environmental changes, with a greater proportion of RPC being directed towards compartments experiencing limited resource availability. Alternatively, the allocation of RPC could shift from sources to sinks as plants processing excess photosynthates. It prompts the question: Does the pattern of RPC allocation vary under global changes? If so, is this variation driven by optimal or by residual C allocation strategies? We conducted a meta-analysis by complicating 273 pairwise observations from 55 articles with 13 C or 14 C pulse or continuous labeling to assess the partitioning of RPC in biomass (leaf, stem, shoot, and root), soil pools (soil organic C, rhizosphere, and microbial biomass C) and CO2 fluxes under elevated CO2 (eCO2 ), warming, drought and nitrogen (N) addition. We propose that the increased allocation of RPC to belowground under sufficient CO2 results from the excretion of excess photosynthates. Warming led to a significant reduction in the percentage of RPC allocated to shoots, alongside an increase in roots allocation, although this was not statistically significant. This pattern is due to the reduced water availability resulting from warming. In conditions of drought, there was a notable increase in the partitioning of RPC to stems (+7.25%) and roots (+36.38%), indicative of a greater investment of RPC in roots for accessing water from deeper soil. Additionally, N addition led to a heightened allocation of RPC in leaves (+10.18%) and shoots (+5.78%), while reducing its partitioning in soil organic C (-8.92%). Contrary to the residual C partitioning observed under eCO2 , the alterations in RPC partitioning in response to warming, drought, and N supplementation are more comprehensively explained through the lens of optimal partitioning theory, showing a trade-off in the partitioning of RPC under global change.

Solute depletion and reduced hydrological connectivity in subarctic patterned peatlands disturbed by mine dewatering

Patterned bog and fen peatlands of the Hudson Bay Lowlands, which form one of the largest continuous peatland complexes in the world, are globally significant stores of carbon and important water conveyance and storage features on the landscape. However, expansion of resource exploration and extraction combined with warmer temperatures associated with climate change may result in reduced water availability to these peatland complexes, potentially disrupting peatland hydrological connectivity and hydrogeochemical cycling. A case study on the effects of reduced water availability on peatland hydrological and geochemical function was conducted near the De Beers Victor Diamond Mine, located 90 km west of Attawapiskat. Active dewatering occurred here over a 12-year period (2007–2019) during which a 1.5 km transect was monitored within the mine impacted radius. Hydrological (streamflow and groundwater levels) and chemical (porewater and surface water samples) parameters were collected at the impacted transect and two nearby unimpacted reference sites. Results demonstrated that impacted peatlands had depleted water storage and spent an average of 50 % less time hydrologically connected than unimpacted peatlands. By the end of the study period, increasingly depleted water storage within the dewatering radius resulted in disproportionately lower flowrates in two tributaries downgradient of the mine-impacted peatlands when compared with the reference sites. Moreover, diminished water storage allowed solute-depleted precipitation to reach greater depths within the peat profile, while stronger downwards gradients suppressed upwards flow into fens, limiting the amount of solute-enriched water reaching the surface. The recovery of fen solute concentrations will be a prolonged process (i.e., decades to centuries) due to the slow rate of upwards diffusion, which may result in the transition of these systems towards ombrotrophic bogs. Further studies should focus on the susceptibility of these impacted systems to further reductions in water availability due to climate change.

Comparison of various sustainable amendments on soil cracking in semi-arid regions

Soil desiccation is an important process that happens mainly in semi-arid regions especially in Central Asia. Soil desiccation leads to higher loss of moisture at shallower depths and also deeper penetration of water, which ultimately reduces water availability and hence impacts the growth of plants for the application of agriculture and green infrastructures. Therefore, minimizing soil desiccation will help maintain higher water availability for plants for agricultural productivity and green infrastructure in Central Asian Region. In literature, various amendments such as natural fibers, cementation, lime, vegetation and biochar have been used to suppress cracking of soil. There is rarely any study that analyses and compares mechanism of crack suppression among the above-mentioned methods. The objective of this study is to explore various sustainable methods of minimizing soil desiccation and compare their mechanisms. Further, the aim is to analyse the feasibility of these methods by revealing their advantages and disadvantages. In order to achieve this objective, 1-D columns were prepared with control soil and amended soil (with fibers, vegetation and biochar). The review also provides insights into their mechanism of suppression of soil cracking by proposing a new factor (i.e., normalized CIF). Based on the proposed factor, the efficiency of biochar and fiber amendments are higher than that of vegetation. Vegetation may or may not have positive impact on cracking of soil depending on their shoot length. Among various amendments, wood biochar (10% content) and coir fiber (at 0.75 % content) seems to have highest efficiency in reducing cracking in soil. Overall, the study aims to develop preliminary guidelines suppressing soil desiccation in semi-arid regions such as Central Asia.

Interplay between climate change and climate variability: the 2022 drought in Central South America

Since 2019, Central South America (CSA) has been reeling under drought conditions, with the last 4 months of 2022 receiving only 44% of the average total precipitation. Simultaneously to the drought, a series of record-breaking heat waves has affected the region. The rainfall deficit during October–November-December (OND) is highly correlated with the Niño3.4 index, indicating that the OND 2022 rainfall deficit is partly driven by La Niña, as observed in previous droughts in this region. To identify whether human-induced climate change was also a driver of the OND 2022 rainfall deficit, we analysed precipitation over the most impacted region. Our findings revealed a pattern of decreased rainfall over the past 40 years, although we cannot definitively conclude whether this trend exceeds what would be expected from natural variations. To clarify if this trend can be attributed to climate change, we looked at 1-in-20-year low rainfall events over the same region in climate models. The models show that the severity of low rainfall events decreases (i.e. they become wetter, the opposite of the trend observed in most weather records), although this trend is again not significant and is compatible with natural variability. Therefore, we cannot attribute the low rainfall to climate change. Moreover, our analysis of effective precipitation potential (evapotranspiration minus rainfall) shows that, in climate models, the increase in temperature does partly compensate for the increase in rainfall but only to offset the wetting, and does not lead to a significant climate change signal in effective precipitation. However, higher temperatures in the region, which have been attributed to climate change, decreased water availability in the models in late 2022, indicating that climate change probably reduced water availability over this period also in the observations, increasing agricultural drought, although this study did not quantify this effect. This means that even though the reduced rainfall is within the natural variability, the consequences of drought are becoming more severe due to the strong increase in extreme heat. The case of the OND 2022 rainfall deficit and the ongoing drought in CSA is a clear example of the interplay between climate variability and human-induced climate change. This shows the importance of considering not only those aspects associated with climate change but also climate variability in order to understand and attribute particular events or trends at the regional level.

The role of seedbanks and hyporheic refuges in supporting benthic invertebrate community resistance and resilience to dry phases

In intermittent streams, aquatic organisms use various strategies to face dry phases, but the relative contribution of these strategies to persist during dry phase remains unclear. Here, we investigated the in situ persistence of benthic invertebrates in the saturated hyporheic sediments and the “invertebrate seedbank” that persists in dry sediments across six Mediterranean intermittent streams. Taxonomic and functional responses within hyporheic and seedbank assemblages were compared with those in the benthic assemblages under connected flow conditions by combining field and mesocosms data. The dry phase duration in each stream was calculated to assess the responses of hyporheic and seedbank assemblages. Taxonomic composition and abundance-weighted traits related to resistance and resilience to face the dry phase in each assemblage type (benthic, hyporheic, seedbank) were determined. Taxonomic (richness and diversity) and functional (richness and dispersion) metrics were also calculated. We found that seedbank and hyporheic assemblages supported up to 16% and 40% of the benthic taxa, respectively. Only taxonomic and functional richness differed between assemblage types. Contrary to previous research, no clear relationship was established between diversity or the abundance of resistance traits and the duration of dry phase; however, a negative linear relationship was identified between the abundance of resilience traits and the duration of the dry phase. The increase in the frequency and duration of drying events due to climate change will reduce water availability in both saturated and unsaturated streambed sediments, compromising the persistence of aquatic biodiversity in intermittent streams.

Drought induces substitution of bacteria within taxonomic groups in the rhizosphere of native maize from arid and tropical regions

In Mexico, maize landraces are usually cultivated in milpa polyculture agroecosystems, which are maintained with ancestral practices, i.e. with very low external inputs such as chemicals and without irrigation systems. Several studies have characterized soil and maize-root microbiota from different milpas, however, robust experimental approaches are necessary to understand the relationship between a healthy microbial community structure and the health of milpa plants. We tested the hypothesis that different maize varieties not only differ in the microorganisms enriched in their rhizospheric environment, but also in the responses of these communities to drought. By suspending irrigation, we induced drought experimentally in three varieties of maize: one landrace from an arid milpa, one from a tropical milpa, and a commercial hybrid. The treatment elicited stress symptoms and growth declines in all three maize varieties. Nevertheless, the maize landrace from arid milpa displayed a better performance in biomass accumulation. The drought treatment did not significantly affect bulk soil bacterial communities; in contrast, all three varieties had shifts in their rhizospheric microbiomes, indicating that these responses were related to the presence of plant roots. The varieties differed in their changes of root-associated microbiota in response to drought, with only Paenarthrobacter genus increasing in all three. Responses mainly consisted of increases in the abundance of certain groups (e.g. Verrucomicrobiota) and substitution of strains within groups (e.g. Group 6 Acidobacteriota, family Streptomycetacea, and many others). The landrace from an arid region had the most bacteria substituted under drought, suggesting that a more stringent selection of microorganisms in roots could be part of the response of this landrace to drought. We propose that drought-tolerant maize landraces from arid milpas could be the source of bacterial strains or communities that aid drought-sensitive varieties in coping with reduced water availability expected due to climate change.

Removal of pollutants from water as a function of sustainable development

The realization of the concept of sustainable development is conditioned by the impact of human activities on natural resources, both renewable and nonrenewable. The basic areas that enable the concept of sustainable development are: food security, energy supply and environmental protection. Protection and use of water as the most important renewable resource is a problem present in all these areas. In the process of food and energy production, water is a raw material and means of work, and in environmental protection, the preservation of quality and protection of water from pollution, as well as water purification, is the most important problem. The constant increase in the number of inhabitants on planet Earth, as well as the accelerated development of society, industrial and technological, has led to the overexploitation of water resources, as well as increasing contamination of water. Decreasing the level of water quality reduces the possibility of its use, which has the immediate consequence of reducing its availability. Certain natural water selfpurification capacities can be reduced in extreme pollution or even completely eliminated. Such trends can lead, in the long term, to a significant reduction in water availability. Therefore, there is a constant need for simpler, more efficient and cheaper treatments for water purification. Conventional methods of water treatment of different origins are often accompanied by undesirable by-products, so modern research is aimed at finding environmentally friendly procedures. The ideal means for water treatment would be one that simultaneously disinfects, decomposes and oxidizes inorganic and organic pollutants, as well as removes colloidal or suspended material and heavy metals, without creating toxic side products. ferrate(VI) is recognized as one of the few such agents and is increasingly used in environmentally friendly water treatment processes. The use of ferrate(VI) as multifunctional chemical reagents has significant advantages in the simplicity and economic benefit of the water treatment procedure (use of one chemical, one dosing and mixing system and less production of sludge), as well as avoiding the formation of toxic by-products. The subject of this chapter is precisely the application of ferrate(VI) in the removal of pollutants from water of various origins in the function of sustainabledevelopment, through: reducing the use of chemicals, reducing the consumption of energy and water resources, environmentally friendly products, etc.

Site matters - Canopy conductance regulation in mature temperate trees diverges at two sites with contrasting soil water availability

Tree-specific canopy conductance (Gc) and its adjustment play a critical role in mitigating excess water loss in changing environmental conditions. However, the change of Gc sensitivity to environmental conditions due to drought remains unclear for European tree species. Here we quantified the environmental operational space of Gc, i.e., the water supply (soil moisture, tree water deficit) and demand conditions (vapor pressure deficit) under which Gc ≥ 50% is possible (Gc50OS), at two sites with different soil water availability for three common European tree species. We collected sap flow and dendrometer measurements for co-occurring Pinus sylvestris, Fagus sylvatica and Quercus petraea growing under different soil hydrological conditions (drier/wetter). These measurements were combined with meteorological variables and soil moisture conditions in five depths. Dendrometer measurements were used to confirm soil water availability patterns. For all analyses, the contrasting soil hydrology between sites was the main driver of Gc response. At the drier sites, F. sylvatica and P. sylvestris reduced their water consumption in response to decreasing soil water supply earlier in the growing season than Q. petraea. However, our analysis on the Gc50OS revealed that at the drier sites, F. sylvatica and Q. petraea reduced the extent of their Gc50OS to a higher degree than P. sylvestris. This indicates a higher level of Gc50OS adjustment to the drier site conditions for the two broadleaved species. These differences were more pronounced when using the dendrometer-derived tree internal water status as proxy for tree water supply. Our results provide preliminary evidence for diverging short-term Gc responses when temperate trees are exposed to prolonged reduction in water availability. These findings suggest that Gc50OS can help to constrain species-specific predictions of water use by mature trees, especially when combined with high-resolution water potential measurements.

Combining Hydrological Modeling and Regional Climate Projections to Assess the Climate Change Impact on the Water Resources of Dam Reservoirs

Climate change may significantly impact the availability and quality of water resources in dam reservoirs by potentially altering the hydrological regime of lake tributaries and the corresponding flow–duration curves. Hydrological models driven by climate projections (downscaled to the watershed scale and bias corrected to eliminate systematic errors) are effective tools for assessing this potential impact. To assess the uncertainty in future water resource availability, resulting from the inherent uncertainty in climate model projections, an ensemble of climate models and different climate scenarios can be considered. The reliability and effectiveness of this approach were illustrated by analyzing the potential impact of climate change on the water availability at Brugneto Lake in northern Italy. This analysis was based on climate projections derived from an ensemble of 13 combinations of General Circulation Models and Regional Climate Models under two distinct scenarios (RCP4.5 and RCP8.5). The semi-distributed HEC-HMS model was adopted to simulate the hydrological response of the basin upstream of the lake. The hydrological model parameters were calibrated automatically via the PEST software package using the inflows to the lake, estimated through a reverse level pool routing method, as observed values. Future water availability was predicted for short- (2010–2039), medium- (2040–2069), and long-term (2070–2099) periods. The results indicate that the uncertainty in reservoir inflow is primarily due to the uncertainty in future rainfall. A moderate reduction in water availability is expected for Brugneto Lake by the end of the current century, accompanied by modifications in the flow regime. These changes should be considered when planning future adaptation measures and adjusting reservoir management rules.

High resilience of campos rupestres plants to the interaction of drought and fire.

The concurrent impacts of multiple disturbances have the potential to modify ecosystem functioning by diminishing recovery capacity and resilience. Nevertheless, it remains uncertain how plant species from tropical communities respond to the cumulative effects of drought and fire. In this study, we evaluated the responses of six plant species from campos rupestres subjected to a mild drought followed by fire and tested if plants subjected to simulated drought show reductions in carbon uptake and depletion of non-structural carbohydrate (NSC) reserves, thus constraining their resprouting. We monitored monthly variations in leaf gas exchange and aboveground biomass over 18 months. Subsequently, an accidental fire occurred in the study area, leading us to collect samples of belowground structures for NSC analyses on the day of the burn. There were no differences in the frequency of resprouting between the above two conditions. Additionally, gas exchange in most species either remained stable or increased after the fire. Drought had no adverse effects on NSC reserves in the belowground structures and may have contributed to species resprouting after fire. The impact of drought pre-conditions on post-fire aboveground biomass was generally minor for most species, except Vellozia nivea, which displayed roughly a 5% reduction in biomass following the drought. Our findings highlight the remarkable resilience of campos rupestres species, even after enduring 18 months of reduced water availability and an unintended fire event. These species demonstrated the capacity to maintain their physiological functions and resprouting capacities after a fire event, underscoring their strong recovery potential.

Effect of Deficit Irrigation on Growth Parameters of the Salvia splendens L. Plant

This study aims to investigate alterations in the developmental parameters of Salvia splendens L., a commonly utilized seasonal flower associated with excessive water consumption in urban green spaces, through the implementation of deficit irrigation practices. Four distinct irrigation treatments, which entailed maintaining the evaporation pot’s water level at 100% (control), 75%, 50%, and 25% of the pot’s water-holding capacity, were established. This study scrutinized 18 growth parameters to assess the impact of varying water application levels. The findings of this research revealed that Salvia splendens L. plants exhibited more substantial improvements in 17 out of 18 assessed parameters when subjected to 75% water application (representing a 25% reduction in water supply) in comparison to 100% water application (with no reduction). Notably, the only parameter negatively affected by reduced water availability in Salvia splendens L. was the diameter of the flowers. Thus, it is recommended to reduce water application by 25% when cultivating Salvia splendens L. in urban areas. Such a measure is expected to yield substantial water conservation benefits in urban landscaping. Consequently, it is advisable to promote the frequent utilization of Salvia splendens L. plants in urban green spaces, given their robust development even under conditions of water scarcity.

Reduced irrigation impact on soil-applied herbicide dissipation and rotational crop response

Abstract Soil-applied herbicides are important for controlling weeds in many crops but risk damage to susceptible rotational crops if they persist. Field studies were conducted in Powell, WY, from 2015 through 2017 to evaluate the effect of reduced water availability on soil-applied herbicide dissipation. Eight soil-applied herbicides, applied to dry bean or corn, were exposed to three season-long irrigation treatments (100%, 85%, and 70% of estimated crop evapotranspiration [ETc]) by overhead sprinkler. Soil samples were collected to a depth of 10 cm from 0 to 140 d after application, and soil herbicide concentrations were quantified using gas or liquid chromatography and mass spectrometry. Herbicide concentrations were regressed over time to produce a soil half-life estimate for each herbicide and irrigation treatment. Reduced irrigation decreased dry bean yield by up to 77% and corn yield by up to 50%. After adjusting for precipitation, the lowest irrigation treatment received 78% and 76% as much water as the full irrigation treatment in 2015 and 2016, respectively. This significantly increased the soil half-life of imazethapyr but did not increase the soil half-life of atrazine, pyroxasulfone, saflufenacil, ethalfluralin, trifluralin, or pendimethalin. Reduced irrigation did not increase carryover injury to rotational crops from these herbicides 1 yr after application. Instead, carryover response was determined by the inherent persistence of individual herbicides. Imazethapyr (0.1 kg ai ha−1) injured rotational sugar beet, and isoxaflutole (0.1 kg ai ha−1) injured rotational dry bean. Pyroxasulfone (0.2 kg ai ha−1), atrazine (2.0 kg ai ha−1), saflufenacil (0.1 kg ai ha−1) + dimethenamid-P (0.6 kg ai ha−1), ethalfluralin (0.8 kg ai ha−1), trifluralin (0.6 kg ai ha−1), and pendimethalin (1.1 kg ai ha−1) did not injure rotational crops regardless of irrigation treatment. Drought stress sufficient to cause up to 77% crop yield loss did not increase soil-applied herbicide carryover.

The use of choline chloride for salt reduction and texture enhancement in bread

Cereal products, and in particular bread, are the main source of salt in human diets. However, salt is a critical ingredient in breadmaking, and its reduction can have a negative impact on bread quality. In order to respond to the World Health Organization (WHO)’s recommendation to reduce dietary salt intake, this research aims to develop a bread recipe "reduced" in salt (sodium chloride or SC) by -50 % and partly substituted by choline chloride (CC). The effect of CC on the properties of bread was studied during baking, cooling and storage of bread. It was observed that partially substituting SC with CC led to an improvement in bread texture. Indeed, CC bread was technologically similar to the control bread. In aqueous solution, CC behaves like an ionic liquid and causes a reorganization of the internal structure of the starch grain. As a result, the staling study highlighted the positive effect of CC on bread texture and on the starch retrogradation. CC limited amylopectin recrystallization by reducing water availability in the medium, consequently slowing down the staling of the bread.

DNA methylome analysis provides insights into gene regulatory mechanism for better performance of rice under fluctuating environmental conditions: epigenomics of adaptive plasticity.

Roots play an important role in adaptive plasticity of rice under dry/direct-sown conditions. However, hypomethylation of genes in leaves (resulting in up-regulated expression) complements the adaptive plasticity of Nagina-22 under DSR conditions. Rice is generally cultivated by transplanting which requires plenty of water for irrigation. Such a practice makes rice cultivation a challenging task under global climate change and reducing water availability. However, dry-seeded/direct-sown rice (DSR) has emerged as a resource-saving alternative to transplanted rice (TPR). Though some of the well-adapted local cultivars are used for DSR, only limited success has been achieved in developing DSR varieties mainly because of a limited knowledge of adaptability of rice under fluctuating environmental conditions. Based on better morpho-physiological and agronomic performance of Nagina-22 (N-22) under DSR conditions, N-22 and IR-64 were grown by transplanting and direct-sowing and used for whole genome methylome analysis to unravel the epigenetic basis of adaptive plasticity of rice. Comparative methylome and transcriptome analyses indicated a large number (4078) of genes regulated through DNA methylation/demethylation in N-22 under DSR conditions. Gene × environment interactions play important roles in adaptive plasticity of rice under direct-sown conditions. While genes for pectinesterase, LRK10, C2H2 zinc-finger protein, splicing factor, transposable elements, and some of the unannotated proteins were hypermethylated, the genes for regulation of transcription, protein phosphorylation, etc. were hypomethylated in CG context in the root of N-22, which played important roles in providing adaptive plasticity to N-22 under DSR conditions. Hypomethylation leading to up-regulation of gene expression in the leaf complements the adaptive plasticity of N-22 under DSR conditions. Moreover, differential post-translational modification of proteins and chromatin assembly/disassembly through DNA methylation in CHG context modulate adaptive plasticity of N-22. These findings would help developing DSR cultivars for increased water-productivity and ecological efficiency.

Beyond the surface: exploring the mycobiome of Norway spruce under drought stress and with Heterobasidion parviporum

The mycobiome, comprising fungi inhabiting plants, potentially plays a crucial role in tree health and survival amidst environmental stressors like climate change and pathogenic fungi. Understanding the intricate relationships between trees and their microbial communities is essential for developing effective strategies to bolster the resilience and well-being of forest ecosystems as we adopt more sustainable forest management practices. The mycobiome can be considered an integral aspect of a tree’s biology, closely linked to its genotype. To explore the influence of host genetics and environmental factors on fungal composition, we examined the mycobiome associated with phloem and roots of Norway spruce (Picea abies (L.) Karst.) cuttings under varying watering conditions. To test the “mycobiome-associated-fitness” hypothesis, we compared seedlings artificially inoculated with Heterobasidion parviporum and control plants to evaluate mycobiome interaction on necrosis development. We aimed to 1) identify specific mycobiome species for the Norway spruce genotypes/families within the phloem and root tissues and their interactions with H. parviporum and 2) assess stability in the mycobiome species composition under abiotic disturbances (reduced water availability). The mycobiome was analyzed by sequencing the ribosomal ITS2 region. Our results revealed significant variations in the diversity and prevalence of the phloem mycobiome among different Norway spruce genotypes, highlighting the considerable impact of genetic variation on the composition and diversity of the phloem mycobiome. Additionally, specific mycobiome genera in the phloem showed variations in response to water availability, indicating the influence of environmental conditions on the relative proportion of certain fungal genera in Norway spruce trees. In the root mycobiome, key fungi such as Phialocephala fortinii and Paraphaeosphaeria neglecta were identified as conferring inhibitory effects against H. parviporum growth in Norway spruce genotypes. Furthermore, certain endophytes demonstrated greater stability in root ecosystems under low water conditions than ectomycorrhizal fungi. This knowledge can contribute to developing sustainable forest management practices that enhance the well-being of trees and their ecosystems, ultimately bolstering forest resilience.

Population Growth and Water Consumption: Chachapoyas Case, 2011 - 2021

Objective: The present research aims to evaluate the impact of population growth on the consumption of drinking water in the city of Chachapoyas during the period from 2022 to 2021 and project the trend until the year 2050. Method: The research followed a mixed longitudinal approach of basic study, with a non-experimental design, involving descriptive, explanatory, and correlational analyses. Based on 11 yearly observations (2011-2021), data from the Municipal Company of Drinking Water and Sewerage Services (EMUSAP) were used for a 20-year projection in Chachapoyas. Result: The results showcase Chachapoyas as an oasis amid the scarcity of drinking water. 96% of water consumption is concentrated in households, while 4% is attributed to the commercial and social sector. The 21% increase in water demand poses a challenge due to population growth and reduced water availability at collection centers. It is projected that per capita water consumption will decline to 1m3 per person by 2049. The relationship between population growth and water availability is critical, necessitating efficient resource management to ensure adequate water access in the future. Conclusion: Authorities should focus on implementing a circular economy, wastewater reuse, and improving pipeline distribution, all of which are critical components for sustainable water management in the city of Chachapoyas.