High Water Stress Research Articles

Relationships between grape composition of Tempranillo variety and available soil water and water stress under different weather conditions

The aim of the research was to analyse the relationship between grape composition of the Tempranillo variety, and available soil water along the growing cycle. The study was conducted in the Rioja DOCa (Qualified Designation of Origin (Spain). Grape composition (berry weight, acidity and phenolic composition) was analysed between veraison and maturity in non-irrigated vines and related to available soil water along the growing cycle. The available soil water (ASW) was simulated for the period 2008–2018, taking into account soil properties and the weather conditions recorded at each location. Soil water was simulated for each plot and year analysed, after calibration in one plot and the ASW was evaluated under the different conditions. The results showed that soil properties conditioned available soil water, which influenced berry weight, acidity, anthocyanins and total polyphenol index. Under the rainfed conditions in which the vines were cultivated, vines suffered from moderate to high water stress in some periods along the growing cycle. The results showed the most critical periods regarding water availability for grape composition. An increase in available soil water between one and three weeks after bloom and at the end of the ripening period increased acidity and decreased pH while an increase in available soil water content between two and seven weeks after bloom and at the ripening period increased berry weight and decreased anthocyanins and other phenolic compounds.

Time-dependent stomatal conductance and growth responses of Tabernaemontana divaricata to short-term elevated CO2 and water stress at higher than optimal growing temperature

A study was designed to evaluate the time-dependent short-term growth adjustments of Tabernaemontana divaricata plants to e[CO2] and WS treatment combinations (combinations) at higher than optimal growing temperature. Three CO2 treatments, i.e., 1000 ppm, 700 ppm (both e[CO2] and 435 ppm (ambient CO2 or a[CO2]) in combination with three WS treatments, i.e, control (CWS; irrigated to field capacity (FC)/4 days), moderate water stress (MWS; irrigated to 70% of FC/4 days) and high water stress (HWS; irrigated to 30% of field capacity/4 days) were randomly applied to plants. Data on stomatal conductance (gs), plant height (PH) and plant girth (PG) were analyzed for three time points (T1, T2 and T3) and for two 14-day periods (FFD and SFD) and one 28-day period (FTD) based on the time points. The 1000HWS (e[CO2] ×WS combination) increased gs at all time points and the 1000MWS increased gs, PH and PG at T3, compared to 435HWS and 435MWS, respectively. Dominant e[CO2] effects over WS effects during SFD period led to significant increase in gs, PH and PG for e[CO2]×WS compared to a[CO2]×WS treatment combinations. This effect during SFD time period, significantly contributed to the increase in gs, PH and PG during FTD, which included the effects of both FFD and SFD periods. Positive repeated measure correlations were observed for gs vs. PH, gs vs. PG and PG vs. PH comparisons. Overall, larger (taller and thicker) plants with higher gs were seen at T3 for e[CO2]×WS combinations compared to the a[CO2]×WS combinations. These results suggest that gs might not be a growth limiting factor for water-stressed T. divaricata plants growing in e[CO2] at higher than optimal growing temperature, provided the temperature stress is not extreme.

Securing future water supply for Iran through 100% renewable energy powered desalination

Iran is the 17th most populated country in the world with several regions facing high or extremely high water stress. It is estimated that half the population live in regions with 30% of Iran’s freshwater resources. The combination of climate change, increasing water demand and mismanagement of water resources is forecasted to worsen the situation. This paper shows how the future water demand of Iran can be secured through seawater reverse osmosis (SWRO) desalination plants powered by 100% renewable energy systems (RES), at a cost level competitive with that of current SWRO plants powered by fossil plants in Iran. The optimal hybrid RES for Iran is found to be a combination of solar photovoltaics (PV) fixed-tilted, PV single-axis tracking, Wind, Battery and Power-to-Gas (PtG) plants. The levelised cost of water (LCOW) is found to lie between 1.0 €/m3 – 3.5 €/m3, depending on renewable resource availability and water transportation costs.

Polyethylene Glycol Mediated Osmotic Stress Impacts on Growth and Biochemical Aspects of Wheat (Triticum aestivum L.)

Seed germination and seedling growth establishment are the most critical growth stages, and drought stress imposed at these stages highly limits crop productivity. In this regard, a hydroponic water culture experiment was conducted with the aim to assess the potential of 20 wheat genotypes against drought stress at the seedling stage. Water deficit was induced through polyethylene glycol (PEG-6000), by maintaining two osmotic potentials in water culture medium, i.e. −0.7 MPa (medium water stress) and −1.0 MPa (high water stress). After seed germination, drought stress was applied for 8 days. Seedlings shoot and root length and biomasses were restricted with an increase in osmotic deficit. Photosynthetic pigments and nitrate reductase activity (NRA) of wheat seedlings were reduced, while proline, total soluble sugars, total phenolics, and mineral ions (K+ and Ca2+) were augmented with the rise in water deficiency in most of the genotypes. On the basis of growth and biochemical attributes, six genotypes (NIA-AA-01, NIA-AA-08, NIA-AA-09, NIA-AA-13, NIA-AA-12, and NIA-AA-14) were categorized as drought tolerant, and three as medium tolerant. These genotypes exhibited better growth by showing the least reduction in root and shoot length, and fresh and dry biomasses, as well as modulation in biochemical processes to survive under water deficit. All studied traits indicated tolerance potential of these genotypes against moderate and extreme drought stress, which could also give better growth in arid and semi-arid regions of the country that facing water scarcity.

INFLUENCE OF WATER STRESS AND PLANT AGE ON THE YIELD AND CHEMICAL COMPOSITION OF ESSENTIAL OIL FROM Cymbopogon winterianus JOWITT

Citronella oil, which is also known as Java citronella oil, is typically obtained from the leaves of Cymbopogon winterianus Jowitt and has been widely used as an antiseptic, fragrance flavor and many other applications. However, systematic studies on the factors affecting the yield and composition of citronella oil are limited. Hence, this study was carried out to investigate the influence of water stress (low to high) and plant age (0.5 to 5 years) on the yield and composition of citronella oil. Citronella leaves were dried at room temperature (26-30 °C) with a relative humidity of 62-74% for 3 days before the citronella oil was extracted using a steam distillation unit. Introducing a high-water stress condition to the plants increased the yield from 0.8% (control) to 1.4% (high water stress) dry weight. The geraniol content slightly increased from 15% to 17% whereas the citronellal content considerably increased from 31% to 44% when the plants were subjected to high water stress in comparison to the control. The oil yield increased with plant age before it reached its plateau at 3.5% dry weight at age 4 years. However, the composition of citronella oil did not significantly vary with plant age.

Using Hyperspectral and Multispectral Indices to Detect Water Stress for an Urban Turfgrass System

Spectral reflectance measurements collected from hyperspectral and multispectral radiometers have the potential to be a management tool for detecting water and nutrient stress in turfgrass. Hyperspectral radiometers collect hundreds of narrowband reflectance data compared to multispectral radiometers that collect three to ten broadband reflectance data for a cheaper cost. Spectral reflectance data have been used to create vegetation indices such as the normalized difference vegetation index (NDVI) and the simple ratio vegetation index (RVI) to assess crop growth, density, and fertility. Other indices such as the water band index (WBI) (narrowband index) and green-to-red ratio index (GRI) (both broadband and narrowband index) have been proposed to predict soil moisture status in turfgrass systems. The objective of this study was to compare the value of multispectral and hyperspectral radiometers to assess soil volumetric water content (VWC) and tall fescue (Festuca arundinacea Schreb.) responses. The multispectral radiometer VI had the strongest relationships to turfgrass quality, biomass, and tissue N accumulation during the trial period (April 2017–August 2018). Soil VWC had the strongest relationship to WBI (r = 0.60), followed by GRI and NDVI (both r = 0.54) for the 0% evapotranspiration (ET). Nonlinear regression showed strong relationships at high water stress periods in each year for WBI (r = 0.69–0.79), GRI (r = 0.64–0.75), and NDVI (r = 0.58–0.79). Broadband index data collected using a mobile multispectral sensor is a cheaper alternative to hyperspectral radiometry and can provide better spatial coverage.

Using environmental clustering to identify specific drought tolerance QTLs in bread wheat (T. aestivum L.).

Environmental clustering helps to identify QTLs associated with grain yield in different water stress scenarios. These QTLs could be useful for breeders to improve grain yields and increase genetic resilience in marginal environments. Drought is one of the main abiotic stresses limiting winter bread wheat growth and productivity around the world. The acquisition of new high-yielding and stress-tolerant varieties is therefore necessary and requires improved understanding of the physiological and genetic bases of drought resistance. A panel of 210 elite European varieties was evaluated in 35 field trials. Grain yield and its components were scored in each trial. A crop model was then run with detailed climatic data and soil water status to assess the dynamics of water stress in each environment. Varieties were registered from 1992 to 2011, allowing us to test timewise genetic progress. Finally, a genome-wide association study (GWAS) was carried out using genotyping data from a 280K SNP chip. The crop model simulation allowed us to group the environments into four water stress scenarios: an optimal condition with no water stress, a post-anthesis water stress, a moderate-anthesis water stress and a high pre-anthesis water stress. Compared to the optimal water condition, grain yield losses in the stressed conditions were 3.3%, 12.4% and 31.2%, respectively. This environmental clustering improved understanding of the effect of drought on grain yields and explained 20% of the G × E interaction. The greatest genetic progress was obtained in the optimal condition, mostly represented in France. The GWAS identified several QTLs, some of which were specific of the different water stress patterns. Our results make breeding for improved drought resistance to specific environmental scenarios easier and will facilitate genetic progress in future environments, i.e., water stress environments.

Coupling Hyperspectral Remote Sensing Data with a Crop Model to Study Winter Wheat Water Demand

Accurate information of crop growth conditions and water status can improve irrigation management. The objective of this study was to evaluate the performance of SAFYE (simple algorithm for yield and evapotranspiration estimation) crop model for simulating winter wheat growth and estimating water demand by assimilating leaf are index (LAI) derived from canopy reflectance measurements. A refined water stress function was used to account for high crop water stress. An experiment with nine irrigation scenarios corresponding to different levels of water supply was conducted over two consecutive winter wheat growing seasons (2013–2014 and 2014–2015). The calibration of four model parameters was based on the global optimization algorithms SCE-UA. Results showed that the estimated and retrieved LAI were in good agreement in most cases, with a minimum and maximum RMSE of 0.173 and 0.736, respectively. Good performance for accumulated biomass estimation was achieved under a moderate water stress condition while an underestimation occurred under a severe water stress condition. Grain yields were also well estimated for both years (R2 = 0.83; RMSE = 0.48 t∙ha−1; MRE = 8.4%). The dynamics of simulated soil moisture in the top 20 cm layer was consistent with field observations for all scenarios; whereas, a general underestimation was observed for total water storage in the 1 m layer, leading to an overestimation of the actual evapotranspiration. This research provides a scheme for estimating crop growth properties, grain yield and actual evapotranspiration by coupling crop model with remote sensing data.

Isotope values of California vole (Microtus californicus) hair relate to historical drought and land use patterns in California, USA.

Increased drought frequency and intensity and agricultural intensification have been key stressors to ecological systems over the past century. Biological proxies (e.g., pollen, tree rings) have been used to track this environmental change; however, linking these changes to the ecology of organisms remains challenging. Here, we link historical drought records to conditions of high water-stress in grassland habitats through the stable isotope analysis of California vole museum specimens (Microtus californicus). Using museum collections spanning 118-years (1891-2009), isotope values of dated hair tissues were associated with statewide drought metrics on the Palmer Drought Severity Index. We observed a positive correlation between δ15N and δ18O values and drought severity. The range in δ15N values (~ 18‰) is greater than what would be expected as a result of dietary shifts across the landscape (~ 3‰), and is likely attributed to the combined effects of physiological responses of M. californicus and isotopic shifts in plant resources with increased water-stress. Geospatial patterns in δ34S values of hair tissues reflect higher baseline isotope values in coastal habitats. However, comparably high δ34S values in the southern-most inland localities suggest sulfur fertilization of croplands and subsequent transfer to surrounding grassland habitats in 34S enriched forms. A broad δ13C range (- 28.7 to - 14.3‰) further suggests the consumption of C3 and C4 plant-based dietary proteins. As shown here, stable isotope analysis of museum collections can provide a climate and land use record based on the physiological performance and ecology of a study species in a region affected intensely by anthropogenic activities.

Influence of cultural practices on the incidence and severity of kiwifruit bacterial canker

Italy has a preeminent rank in kiwifruit industry, being the first exporter and the second largest producer after China. However, in the last years kiwifruit yields and the global cultivated area considerably decreased, due to the pandemic spread of the bacterial canker caused by Pseudomonas syringae pv. actinidiae (Psa). Several climatic conditions and cultural practices affect the development of the bacterial canker. With the emergence of this devastating disease, the use of pesticides rapidly increased and therefore the kiwifruit quality can be maintained only by ensuring agricultural practices that reduce the need of toxic xenobiotic compounds. This research work focused on the impact of agricultural practices on disease development and spread. High nitrogen fertilization, iron deficiency and water stress were related to more severe symptoms. Open canopies allow a better irradiation, aeration, and penetration of phytosanitary treatments. Synthetic gibberellins reduced disease incidence and severity in controlled conditions. Finally, the preliminary guideline harmonizing the best cultural practices with the current disease control inputs is provided.

THE ECONOMIC AND SOCIAL IMPACTS OF WATER SCARCITY IN THE IR IRAN

The past 15 years of exceptionally severe water scarcity in the Islamic Republic of Iran have resulted in the desertification and salinity of formerly arable lands, drying out of Iranian lakes and rivers, and quickly shrinking groundwater resources, while water demand has risen, along with the size of the Iranian population, of which over 70% lives in urban areas now. We have aimed to discover the causes of water scarcity in the IR Iran and evaluated its social and economic impacts. First, we computed the Weighted Anomaly Standardized Precipitation (WASP) Index for the period of 1979-2014. To illustrate the social impact of water scarcity, we analyzed the current water risk for the twenty most populous Iranian cities, by employing the composite index approach to translate hydrological data into comprehensible indicators of water related risks, and made a projection for 2020-2030, by modeling potential changes in the future demand and supply of water. To demonstrate the economic impact of water scarcity, we evaluated the overall agricultural contribution to the IR Iran GDP. We have found that the 1999 severe drought in the IR Iran commenced a period of unusually dry conditions that is still ongoing. The rapidly growing Iranian urban populations presently experience a medium to extremely high overall water risk , with extremely high baseline water stress that, in part, is due to the lack of upstream protected lands. The relationship between baseline water stress and drought severity has been determined as weak , confirming that other factors than drought are equally or more important contributors to the existing water risk. Our projection calculations indicate that Iranian urban populations will continue to experience an extremely high water stress for the coming decade . Due to the fast growth of these populations as well as considerable rise of value added to the IR Iran GDP by other sectors of the national economy, the contribution of agricultural production to the national GDP has declined from about 25% to under 10% (although its total yield has risen considerably) during the past 30 years. This decrease has been directly proportional to the increased foreign food imports , dependency on the IR Iran oil exports and reduction in the non-oil exports. The main causes of water scarcity in the IR Iran appear to be due to climatic factors, insufficient environmental protection, and over-exploitation and mismanagement of water resources, especially by the agricultural sector. In conclusion, our study proposes anti-wasting water management action plan that recommends shifting the IR Iran government response to water scarcity from reactive survival strategies to proactive crisis prevention, with emphasis on safeguarding, monitoring, early warning, and effective step-by-step preparedness and readiness, and by laterally integrating water management between all levels of the IR Iran government, including local, regional and national, for a sustainable, resilient and prosperous economy of the Islamic Republic of Iran now and in the future.

Does Water Efficiency Reduce Water Consumption? The Economy-Wide Water Rebound Effect

Governments stimulate efficiency measures to save water resources, particularly in areas with high water stress and those that experience droughts. However, economic theory and some empirical studies tell us that the effects of efficiency improvements of a resource may not lead to a global reduction in the use of that resource. We assess the effects of improving water resources productivity in Spain on the global use of water using a dynamic water-economy computable general equilibrium model. We set an overall annual improvement of water efficiency of 50% and find that the economy-wide water rebound effect is 100.47%. This means that there are no savings of water after an efficiency improvement, and there is actually a slight global increase in water use.

Spatially Explicit Large-Scale Environmental Risk Assessment of Pharmaceuticals in Surface Water in China.

With improving healthcare and an aging population, the consumption of human pharmaceuticals in China has been increasing dramatically. Environmental risks posed by many active pharmaceutical ingredients (APIs) are still unknown. This study used a spatially explicit dilution-factor methodology to model predicted environmental concentrations (PECs) of 11 human-use APIs in surface water for a preliminary environmental risk assessment (ERA). Median PECs in surface water across China range between 0.01 and 8.0 × 103 ng/L for the different APIs, under a moderate patient use scenario. Higher environmental risks of APIs in surface water are in regions with high water stress, e.g., northern China. Levonorgestrel, estradiol, ethinyl estradiol and abiraterone acetate were predicted to potentially pose a high or moderate environmental risk in China if consumption levels reach those in Europe. Relative risks of these four APIs have the potential to be among those chemicals with the highest impact on surface water in China when compared to the risks associated with other regulated chemicals, including triclosan and some standard water quality parameters including BOD5 (5-day biological oxygen demand), COD (chemical oxygen demand), Cu, Zn, and Hg and linear alkylbenzene sulfonate. This method could support the regulation of this category of chemicals and risk mitigation strategies in China.

An eco-efficiency evaluation of community-scale rainwater and stormwater harvesting in Aarhus, Denmark

Urban areas in Denmark are currently challenged by the increase in extreme precipitation events, resulting in heightened flood risk, and higher water stress caused by population growth. Therefore, we need to diversify water resources and reshape stormwater management.Our study evaluated the potential for increasing economic value while reducing the environmental impacts of implementing new concepts for non-potable rainwater use in a new urban development. We analysed five alternatives: a conventional groundwater-based drinking water system (A0-GW), three types of centralised ways of treating runoff collected from impervious areas (CT1-CT3) and a decentralised system for rainwater harvesting (DT-RWH). All five alternatives included stormwater collection with a system of basins and trenches for flood protection.Potential environmental impacts were quantified by life cycle assessment (LCA), while the economic system value was assessed in terms of total value added (TVA). The LCA and TVA were evaluated over the entire water chain, including effects at the end-user level and an estimation of the single economic added value for each stakeholder. A combined LCA and TVA provided an assessment of eco-efficiency.The four runoff-based alternatives exhibited up to 95% reduced freshwater depletion impacts compared to the conventional drinking water system. In all alternatives, more than 94% of the ecotoxicity impacts were due to the discharge of metals (zinc and copper) from runoff into freshwater, and the three centralised treatment alternatives (CT1-CT3) reduced ecotoxicity by 80%. Overall, the two centralised ultrafiltration plants (CT1-CT2) showed the lowest effects in all impact categories, except for reserve base resource depletion, which was affected by stainless steel production.CT1-CT2 also showed slightly higher TVA (app. +3–5%) compared to conventional treatment. The TVA for CT3 and DT-RWH was found to be between −14% and −116% lower than conventional treatment. Except for the reserve base resource depletion category, CT1 and CT2 were considered the more eco-efficient alternatives compared to the conventional drinking water system.

Effects of water stress on the growth, physiology and biochemical properties of oil palm seedlings

Climate change poses significant challenges to the production of oil palm as its output can be directly affected by abiotic stress, especially drought. Thus, this research was designed to investigate the effect of different water stress regimes on the physiology of oil palm seedlings to determine the optimum amount of water that should be applied. Three-month-old Tenera hybrid (Dura X Pisifera) oil palm seedlings were arranged in randomised completely block design (RCBD) and treated with four irrigation regimes: 100% ER (evapotranspiration replacement; well-watered), 75% ER (moderate water stress), 50% ER (high water stress) and 25% ER (severe water stress). Growth, carbon assimilation and biochemical parameters were recorded during the experiment. The results showed severe water stress decreased vegetative plant growth, leaf water potential, relative water content, leaf moisture content, stomatal conductance, transpiration rate, net photosynthesis, water use efficiency and fv/fm (maximum efficiency of photosystem II). The level of malondialdehyde (MDA) and proline increased under water stress. Regarding irrigation, 100% ER (control) was most effective on most parameters, but there was no significant difference to 75% ER. Thus, to optimise the water utilisation, supplying 75% water from soil field capacity on oil palm seedlings is the best option.

Assessment of algal biofuel resource potential in the United States with consideration of regional water stress

Algae is a promising feedstock for biofuels. Because scaling up the production of algae-based biofuels consumes a significant amount of water, it is important to consider the impact it has on water stress. This study evaluates the potential for algae-derived biofuel production in the United States (US) and considers regional water stress. We used the Biomass Assessment Tool (BAT) to identify potential sites in the US that meet land, biomass productivity, and CO2 co-locating criteria. We quantify the water stress impacts of algal biofuel production in terms of water scarcity footprint using water consumption from BAT, and the water stress indicator from Available Water Remaining for the US (AWARE-US) system. We assess long-term (20 billion gal per year [BGY]) and near-term (5 BGY by 2030) renewable diesel (RD) production targets. To select suitable algae sites, we consider biomass yield and water use with and without water stress constraints. We found that ranking sites based on biomass yield results in a high water stress impact (24.5 × 103 US equivalent BGY [BGYe]) for the long-term RD target. If we instead rank sites on water use efficiency, water consumption decreases on average by 62%, with an average reduction in biomass yield of 25%. To reconcile tradeoffs between biomass yield and water stress impacts, water stress indicator (AWARE-US) that represents relative water availability by region can be applied while considering biomass yield. This strategy removes sites located in water-stressed areas and keeps high-productivity sites. For the long-term RD target, this reduces water stress impacts by 55% (13.8 BGYe) without lowering yield or 97% (24.2 BGYe) with moderately lower (4%) yield, compared to the sites ranked by biomass yield alone. The results demonstrate that incorporating water stress into energy-scale algae biofuel production planning is key to achieving synergies between biofuel yield and fresh water stress impacts.

Geospatial and techno-economic analysis of wind and solar resources in India

Using geospatial and economic analysis, we identify abundant renewable resources in India — 850–3400 GW for onshore wind, 1300–5200 GW for utility-scale solar photovoltaic (PV), 160–620 GW for concentrated solar power (CSP, with 6 h-storage). However, these resources are concentrated in the western and southern regions. Deriving capital costs from India's 2017–18 auction prices, we estimate the 5th and 95th percentiles of levelized costs of energy generation ranging from USD 47–52 per MWh for solar PV and USD 42–62 per MWh for wind. Karnataka, Maharashtra, Tamil Nadu, and Telangana are the best states for access to high-voltage substations, but transmission investments in Gujarat, Rajasthan, Andhra Pradesh, and Madhya Pradesh are needed to harness significant renewable resources. More than 80% of wind resources lie on agricultural lands where dual land use strategies could encourage wind development and avoid loss of agriculturally productive land. Approximately 90% of CSP resources and 80% of solar PV resources are in areas experiencing high water stress, which can severely restrict deployment unless water requirements are minimized. Finally, we find co-location potential of at least 110 GW of wind and 360 GW of solar PV, which together could meet 35% of electricity demand in 2030.

Climate change impacts on availability and vulnerability of Indonesia water resources

Global climate change has been recognized as a challenging isue in the past decades and with significant impacts on many aspects of human life, especially on the availability and vulnerability on water resources. Food production requires a large portion of water demands and directly related to population that is still increasing in Indonesia. Therefore food production will have direct impacts on land and water resources with great implications on environmental degradation. Water resources development and management in Indonesia under stress in changing climate is considered still in low risk of water scarcity nationally with space-time variation, such as for Java Island and many developing urban areas already at high water stress level. Sustainability of water resources in such areas could be achieved only through trade-off and balancing the competing water demands and available supply, satisfying the law of mass conservation as a sufficiency condition. These high-risk water stress areas would need development of water storage and irrigation infrastructures and adoption of crop-water productivity strategy to improve water use efficiency for food and agricultural production and ensure water and food security of the country.

Evaluation of Water Scarcity in Selected Countries of the Middle East

The primary goal of this article is to evaluate water scarcity in selected countries of the Middle-East and assess the impact on agricultural production. To begin with, the Weighted Anomaly Standardized Precipitation (WASP) Index from 1979 to 2017 was spatially computed for Iran, Iraq and Saudi Arabia. In order to demonstrate the effect of reduced levels of water, the water shortage situation in cities with the population higher than one million was examined. This was accomplished by utilizing the Composite Index approach to make water related statistics more intelligible. A projection for the years of 2020 to 2030 was created in order to demonstrate possible changes in the supply and demand for water in selected countries of the Middle-East. In regards to evaluating the economic effects of water shortages on agricultural sector, effects of lower precipitation on agricultural production in Iran, Iraq and Saudi Arabia were estimated. With ever-increasing urbanization, all countries are currently experiencing a moderate to high water risk. Our research points to excessively high water stress for most analyzed cities through the year 2030. Also, it is demonstrated how much precipitation decreases influence agricultural production in Iran, Iraq and Saudi Arabia. From the analyzed countries, some evidence is found that precipitation negatively influences crop production, primarily for Iran.

Enzyme systems for effective dag removal from cattle hides

The effective removal of recalcitrant manure balls (dags) composed of dung, hair, soil, urine, sugars and straw from the hides of cattle remains a significant issue for the livestock industry. Dags must be removed to reduce the likelihood of microbial meat contamination and irreversible damage during leather processing. Current removal methods require extensive washing over many hours per animal resulting in high water use, costs and stress to the animal. Enzymes can be highly effective catalysts for the breakdown of biomass but previous research into the enzymatic removal of dags has had limited success. This work investigates the latest commercial enzyme preparations and classes of enzymes never previously tested for dag removal in new formulations. Cellulase, xylanase, laccase and α-amylase enzymes were applied to target the lignocellulosic and starch components of the dags. Protease enzymes that targeted the interaction between the dag and the hair, were also investigated as a novel approach for dag removal from cattle. Our results show that the application of a protease with keratinolytic activity is crucial for dag removal, weakening the framework of hairs at the point of attachment between the hair and the dag, as well as potentially degrading adhesive protein that may hold the structure together. The addition of a reducing agent and surfactant to the treatment facilitated optimal decomposition of the dag structure. Implementation of these enzymatic dag removal systems could significantly reduce the time, water use, animal stress and costs of cleaning cattle in the red meat industry.