Water Scarcity Scenarios Research Articles

Effects of the cessation of fish-processing effluent discharges on the soil microbiome associated with saltbush patches

In the present scenario of global water scarcity, treated wastewater from some industries -such as the fishing industry- is an interesting resource to consider for irrigation purposes. In a previous study in a Patagonian steppe site dominated by the native halophile shrub Atriplex lampa, fish-processing effluent discharges induced soil salinization, changes in the soil prokaryotic community structure and a reduction of its diversity. In this study we aimed to test if a period without effluent discharges allowed the recovery of the microbial community in soils from this Patagonian steppe site, by analyzing the prokaryotic communities of A. lampa patches during the fish-processing effluent discharges and four years after cessation of such discharges (sites ES1 and ES2, respectively). Additionally, we aimed to test if the soil prokaryotic community of A. lampa patches either exposed to effluent discharges (ES2) or from a coastal dune site (Du) share a common core microbiome as a result of their same shrub cover and similar soil salinity. Regarding the comparison between ES1 and ES2, prokaryotic richness estimators (Chao1 and ACE) increased significantly in ES2. In addition, the cessation of effluent discharges induced a rise of Actinobacteria, and a recovery of some oligotrophic phyla, which had decreased during the effluent discharge period. Regarding the comparison between ES2 and Du, the core microbiome in soils associated with A. lampa patches consisted of just a few taxa. Moreover, Du site revealed a signature of dune-specific prokaryotes comprising halotolerant/halophilic microorganisms adapted to marine and intertidal environments, whilst no such signature was observed in ES2. Overall, our results contribute to unraveling the soil prokaryote diversity associated to A. lampa as well as to a better understanding of the microbiomes from saline environments, having valuable implications for a sustainable reuse of fishing industry wastewaters for irrigation.

Impact of wild solanaceae rootstocks on morphological and physiological response, yield, and fruit quality of tomato (Solanum lycopersicum L.) grown under deficit irrigation conditions

It has been established that climate change has a direct impact on water availability, an essential resource for agricultural development. As a result, controlling, mitigating, and adapting to water deficit requires the advancement of research on promising wild flora species. As recent studies have shown, wild relatives of certain cultivars are tolerant to adverse factors, enabling the development of sustainable and resilient agriculture. The present study evaluated the morpho-physiology and productivity of tomato scions grafted on wild Solanaceae (Datura stramonium, Solanum sisymbriifolium, Solanum quitoense, and Cyphomandra betacea) grown under water deficit conditions (100% ETc - high level, 75% ETc - moderate level, 50% ETc - medium level, and 25% ETc - low level). The results showed that tomato plants grafted on Datura stramonium rootstocks performed better morpho-physiologically under deficit irrigation. The improved osmoregulation caused by a higher relative water content (98.49%) allowed the scion to be more tolerant to water stress. In addition, these scions showed high water potential during their phenological stages (vegetative −0.47 MPa, flowering −0.59 MPa, and production −0.64 MPa), as well as improved photosynthetic efficiency. The overall tolerance of the scion resulted in better yield (8.14 kg/plant) with higher number of commercially valuable fruits. The D. stramonium rootstock allowed better management and use of irrigation water, increasing productivity (54.95 kg/m3); that is, it is presented as a species with potential for establishing tomato production areas in scenarios of water scarcity or cultivation under deficit irrigation.

WATER USE AND SUPPLY IN THE NORTHERN REGION OF BAJA CALIFORNIA, MEXICO

The demographic and economic growth in the northern region of the Mexican state of Baja California has led to increased water use and competition for this resource among diverse consumer sectors. The regional dynamism has made it increasingly difficult to meet the demand for water provision. The aim of this investigation was to allocate the water withdrawn from the Mexicali Valley and San Luis Río Colorado (SLRC) aquifers in a scenario of water scarcity among the various consumer sectors by municipality of the states of Baja California and Sonora, as well as to determine the price that would allow for a reduction in the amount of water taken from the aquifers. A spatial equilibrium model was formulated and validated, considering fixed supply and functions of demand. The 2019 results show that the total demand for water from municipalities in residential, commercial, industrial, agricultural and livestock sectors were 197.2, 21.7, 16.7, 758 and 5.7 hm3, with Tijuana standing out in the first three sectors, whereas Mexicali and SLRC were highlighted in the farming sector. Regarding the water price, the Tijuana, Tecate, and Ensenada municipalities pay a high tariff for its use, whereas Mexicali and SLRC pay the lowest tariffs. A 10 % reduction in water availability would be achieved if the price in the agricultural sector in Mexicali and SLRC increased by 20 and 22 %, respectively, over the base price. As the price rises, the demand in this sector for both municipalities would decrease by 2.6 %.

A stand-alone remote sensing approach based on the use of the optical trapezoid model for detecting the irrigated areas

Under the current water scarcity scenario, the promotion of water saving strategies is essential for improving the sustainability of the irrigated agriculture. In particular, high resolution irrigated area maps are required for better understanding water uses and supporting water management authorities. The main purpose of this study was to provide a stand-alone remote sensing (RS) methodology for mapping irrigated areas. Specifically, an unsupervised classification approach on Normalized Difference Vegetation Index (NDVI) data was coupled with the OPtical TRApezoid Model (OPTRAM) for detecting actual irrigated areas without the use of any reference data. The proposed methodology was firstly applied and validated at the Marchfeld Cropland region (Austria) during the irrigation season 2021, showing a good agreement with an overall accuracy of 70%. Secondly, it was applied at the irrigation district Quota 102,50 (Italy) for the irrigation seasons 2019–2020. The results of the latter were instead compared with the data declared by the Reclamation Consortium, finding an overestimation of irrigated areas of 21%. In conclusion, this study suggests an easy-to-use approach, eventually independent of reference data such as agricultural statistical surveys or records and replicable under different agricultural settings in continental or Mediterranean climates to support stakeholders for regular estimation of irrigated areas in different growing years or detecting eventual unauthorized water uses. However, some uncertainties should be considered, needing further analyses for improving the accuracy of the proposed approach.

Fiber Quality, Yield, and Profitability of Cotton in Response to Supplemental Irrigation with Treated Wastewater and NPK Fertilization

Cotton yield under the rainfed farming system in tropical semi-arid regions is significantly decreased by prolonged dry spells. In this context, supplemental irrigation (SI) with treated wastewater emerges as a strategy for the sustainability of agricultural production besides contributing to the reduction of fertilizer costs. The objective of this research was to evaluate the productivity, photosynthetic parameters, fiber quality, and profitability of cotton cultivation, under supplemental irrigation (SI) with municipal treated wastewater (MTW), with and without mineral fertilization. The treatments consisted of three water scenarios (normal, drought, and severe drought), defined by the historical series of precipitation data of 30 years, and two treatments of supplemental irrigation with MTW, with or without NPK fertilization. SI with treated wastewater increased cotton yield in all three scenarios (normal, drought, and severe drought) by approximately 29%, 255%, and 251%. Longer dry spells in drought and severe drought scenarios increased the volume of SI with MTW, resulting in greater nutrient input to the soil, improved photosynthetic response, higher physical water productivity, reduction in fertilizer costs, and higher farmers’ income. Therefore, our results show the importance of using treated wastewater in supplemental irrigation of cotton under scenarios of water scarcity in tropical semi-arid regions.

Reallocation of water in agriculture under drought conditions as economic efficiency maximizer

Objective: To analyze the water market scheme for water rights transfer, which could enable the increase of the economic efficiency of water use in the Irrigation District 011 - Alto Río Lerma. Design/Methodology/Approach: Using linear programming, a first model was developed to determine shadow prices in three water scarcity scenarios (15, 30, and 50% water resources reduction) and to compare them with the irrigation fees currently paid in Irrigation District 011. The second model established a water market scheme, using the same water scarcity scenarios (15, 30, and 50%). This model was developed to compare the net profit of the producers within and outside the water right transfer market. Results: The average shadow price of water is MN$ 3.9 m-3; this amount is higher than the irrigation fee currently paid (MN$ 0.15 m-3). The water transfer percentages are 25.8, 29.1, and 36.1%, obtaining 7.6, 7.4 and 11.7% net profit, respectively, for each water scarcity scenario (15, 30, and 50%). Study Limitations/Implications: The research was carried out based on the data from two out of the 11 irrigation modules included in Irrigation District 011. These modules are the most representative, both in extension and crop variety. Findings/Conclusions: The existence of a water market confirms the advantages of an increase in the net profit of the producers under drought conditions, included within the area of Irrigation District 011.

Assessing almond response to irrigation and soil management practices using vegetation indexes time-series and plant water status measurements

Current water scarcity scenario has led to the implementation of sustainable agricultural practices intended to improve water use efficiency. The present work evaluates during three agricultural campaigns (2018–2020) the response of a young almond orchard to two management practices in terms by combining remote sensing indexes (Normalized Difference Vegetation Index, NDVI; and Soil Adjusted Vegetation Indexes, SAVI) and physiological/morphological measurement (stem water potential, Ψstem; trunk perimeter and canopy diameter). The management practices included (i) sustained deficit irrigation and (ii) soil management. Severe deficit irrigation resulted in lower vegetation indexes (VI) values, Ψstem and tree dimensions (13 %, 23 % and 14 % lower, respectively) than those obtained for full irrigation strategy; whereas moderate deficit irrigation did not affect any of the parameters analysed. The presence of vegetation cover in the inter-row resulted in a VIs increase (19–42 %) and in lower tree dimensions (reductions of 7–8 % for trunk perimeter and 0.34–0.37 m for canopy diameter) when compared to bare soil treatment, but did not have any influence on Ψstem. The present study proves the suitability of remote sensing and physiological measurements for assessing almond response to the different management practices.

Effect of Feed Water Temperature on Reverse Osmosis Performance in a Borehole Water Desalination Plant: Numerical and Experimental Validation

Reverse osmosis is a water desalination process with the help of a semi-permeable membrane to deal with the global scenario of water scarcity. The study was performed by installing Reverse Osmosis (RO) plant coupled with photovoltaic (PV) panels in the LPHE-modelling and simulations laboratory at the Faculty of Sciences, Mohammed V University, Rabat, Morocco. The principal purpose of the study was to investigate water quality and its proposed treatment by taking water samples from Ain El Atti, Errachidia, Morocco. Water quality testing confirmed the high value of Total Dissolved Salts (TDS), which made water saline. The current article will provide mathematical modelling of the RO process based on the theory of diffusion and mass transfer of solution. The results of the mathematical simulation model were validated with the help of a series of experiments done in the pilot laboratory. The study also focused on finding the impact of feed water temperature on the thermodynamic parameter of water (i.e., TDS, flow rate (Q), Specific Energy Consumption (SEC), recovery rate (Y), and retention rate (TR)). Finally, a comparison of results of both models and per cent error in results were calculated, which depicted a higher validity of the mathematical model by showing closer proximity of more than 85% of its results with the actual experimental setup.

Assessment of Land Surface Temperature Estimates from Landsat 8-TIRS in A High-Contrast Semiarid Agroecosystem. Algorithms Intercomparison

Monitoring Land Surface Temperature (LST) from Landsat satellites has been shown to be effective in the estimation of crop water needs and modeling water use efficiency. Accurate LST estimation becomes critical in semiarid areas under water scarcity scenarios. This work shows the assessment of some well-known Single-Channel (SC) and Split-Window (SW) algorithms, adapted to Landsat 8/TIRS, under the conditions of a high-contrast semiarid agroecosystem. The recently released Landsat 8 Level-2 LST product (L8_ST) has also been included in the performance analysis. Ground measurements of surface temperature were taken for the evaluation during the summers of 2018–2019 in the cropland area of the Barrax test site, Spain. A dataset of 44 ground samples and 11 different L8/TIRS dates/scenes was gathered, covering a variety of crop fields and surface conditions. In addition, a simplified Single Band Atmospheric Correction (L-SBAC) was introduced based on a linearization of the atmospheric correction parameters with the water vapor content (w) and a redefinition of the emissivity threshold for the emissivity correction in the study site. The best results show differences within ±4.0 K for temperatures ranging 300–325 K. Statistics for the L-SBAC result in a RMSE of ±1.8 K with negligible systematic deviation. Similar results were obtained for the other SC and SW algorithms tested, whereas an overestimation of 1.0 K was observed for the L8_ST product because of inappropriate assignment of emissivity values. These results show the potential of the proposed linearization approach and set the uncertainty for LST estimates in high-contrast semiarid agroecosystems.

Developing an automatic conjunctive surface-groundwater operating system for sustainable agricultural water distribution

Groundwater extraction from aquifers is the primary approach for supplying agricultural water demand due to the inadequate, unfair, and unreliable distribution of surface water (SW) systems. In this regard, the present study developed an automated operating system for conjunctive surface and groundwater (GW) resources. By centralized model predictive control (CMPC), an automated SW distribution system was developed in MATLAB and integrated with the groundwater modeling system (GMS) to provide an intelligent SW-GW conjunctive operating system in water scarcity scenarios. A controversial irrigation district in central Iran is selected as the test case in Iran. GW extraction from active tube-wells in the SW distribution system's territory includes 39%, 21%, 40% deep, semi-deep, and shallow. Besides, about 65% of energy consumption is related to over-exploitation in deep wells. The notable point of automating the SW system is the high capability of CMPC to control fluctuations in all canal reaches so that the dependability and adequacy of water distribution become reasonable even under severe scenarios. Intelligent SW-GW operating system led to an uprise of 0.1–2.2, 0.2–3.2, 0.4–3.9, 0.7–6.9, 1.5–9.1, and 3.8–13.5 m in the aquifer water level, respectively, within 12, 2, 36, 48, 60, and 120 months. Besides, Water extraction reduction from the aquifer after one year is about 16%, and the reduction of annual energy consumption is around 81%. The proposed method enables authorities to promote the SW distribution in practical, implementable, and step-by-step planning to reduce GW extraction from tube-wells based on actual water reduction potential.

Effect of acetylsalicylic acid and ammonium sulphate on productive and physiological parameters in Stipa caudata under water shortage conditions

Stipa caudata is a grass native to low rainfall areas in Argentina and Chile, considered an excellent potential candidate for biofuel production or soil restoration programmes. This study aimed at analysing the effects of ammonium sulphate (AMS) and acetylsalicylic acid (ASA) on the productivity and biochemical traits of plants of this species under water scarcity conditions. The experimental work was carried out on plants grown outdoors using a randomised block plot design. Several yield and biochemical parameters related to resistance to water scarcity were analysed in plants treated with AMS or ASA. Plants in the treatments with ASA and AMS had higher total chlorophyll content than the others. Concerning ion content, water-restricted plants treated with AMS had similar values to irrigated plants. Regarding the osmoprotectants and antioxidants, treated plants had increased concentrations of proline and total flavonoids. Under water stress, plants had higher APX activity and there was an A x B interaction for CAT and SOD activity. The results obtained show that the use of ASA and AMS in some crops or in environmental restoration programmes could be a useful tool to cope with future climate scenarios of water scarcity.

Effect of Banana-Waste Biochar and Compost Mixtures on Growth Responses and Physiological Traits of Seashore Paspalum Subjected to Six Different Water Conditions

The effects of pyrolyzed agricultural waste generated from banana leaves on the development and physiological responses of Paspalum vaginatum in different water conditions were investigated. X-ray diffraction (XRD) and Fourier-transform infrared (FTIR) computations were utilized to describe the banana-waste biochar and determine the crystalline structure and functional groups. A plastic pot was used in two trials to examine the effectiveness of the studied biochar under two situations (well-watered Ww and limited-watered Lw). Seashore paspalum was cultivated in loam soil that had been modified with biochar as a single addition and a biochar compost mix. Six water scarcity scenarios were chosen (100, 80, 60, 25, 20, and 15% of water holding capacity (WHC) of the control soil). To analyze the varied responses of P. vaginatum in well-watered and limited-water environments, principal component analysis (PCA) was used. Under Ww, photosynthesis, biomass, fluorescence, and chlorophyll content increased, whereas, under Lw and control, they declined. Biochar and compost combinations enhanced the relative water content (RWC) more than biochar alone or in combination. Conversely, stomatal density in drought-stricken plants showed the reverse trend.

The Role of Small Reservoirs in a Water Scarcity Scenario: a Computational Approach

The Role of Small Reservoirs in a Water Scarcity Scenario: a Computational Approach

Methods to enhance the productivity of solar still: A review

Water is the main factor for livings on earth. The requirement for potable water is rising gradually because of the rapid population growth. 71% earth’s area is occupied by oceans. So the availability of brine & brackish water is around 75% but for the human being all purposes like drinking, laboratories purposes & automobiles batteries we need fresh water. To conquer the availability scenario of clean water scarcity, the conversion of seawater into freshwater is needed. In the present era, there are various techniques available for conversion but solar distillation is the most economical technique to gain potable water. To enhance conversion factors different solar still studied and compared with several output parameters, also this paper demonstrates the enhancing yield parameter through experimentation at various depth, different phase change material, design modification, etc. & their prospect.

Compressive strength of SF and FA based self curing HSSC: An experimental study

Typical High-strength concrete (HSC) mixtures are characterized by low water-cementitious material ratio, high content of cementitious material, and the incorporation of admixtures. Concrete needs a favourable atmosphere by providing moisture for a minimum base period of 28 days for hydration and to attain targeted strength. In the present scenario of water scarcity, the water required for curing concrete is a troublesome constraint. Self-curing concrete is one of the peculiar concretes for coping with insufficient curing caused by human error. The prime goal of this study is to identify the self-curing compound’s optimum dosage for High Strength Self-Compacting Concrete (HSSC). Likewise, it is aimed to investigate the compressive strength characteristics of HSSC. For the study, a self-curing agent namely “PEG-400” with varying percentages (0.5%, 1%, 2% & 3% by weight of cement) was investigated. An attempt was made to identify the effect of the self-curing compound on the fresh and hardened properties of HSSC, workability tests and compressive strength tests were conducted. The tests on hardened concrete were conducted after curing for 28 days for conventional HSC specimens and ambient curing for HSSC. It was observed that with the addition of 1% of PEG-400 self-curing compound, the compressive of HSC was found to be increased by 1.86% in comparison with the conventionally cured HSC. It was observed that with the addition of 1% of PEG-400 self-curing compound, the compressive strength of HSSC was found to be increased by 1.87% in comparison with the conventionally cured HSSC.

AHP and GIS-based Delineation of Groundwater Potential of Papum Pare District of Arunachal Pradesh, India

Abstract Water is crucial to human survival. Studies on surface water are well documented but precise knowledge of groundwater resources is difficult. Thus, accurate knowledge of groundwater resources could meet the necessities of water at present and in the long run. Application of the Analytic Hierarchy Process (AHP) and Geographical Information System (GIS) together with multicriteria parameters has emerged as an efficient technique for delineation of groundwater potential in recent decades. However, no efforts to delineate the groundwater potential have been attempted in the study area till date. Hence, in this study, the groundwater potential of Papum Pare district of Arunachal Pradesh was delineated by combining AHP, overlay analysis, GIS, and ten thematic layers (geomorphology, geology, slope, lineament density, drainage density, rainfall, distance from the major river, topographic wetness index, soil texture, and land use/land cover). The results show about 64% of the area under poor groundwater potential. Moderate and good groundwater potential is found in 31% and 5% of the area. Map-removal and single-parameter sensitivity analyses revealed that the groundwater potential map is most sensitive to the annual average rainfall with a mean variation index of 1.05% and a weight of 19.07%. The flood/alluvial plains, Siwalik formations with sediments, and level to gentle slopes receiving high rainfall show good potential, and the dissected hills/ valleys, metamorphic rock assemblages, steep slopes with low rainfall reveals poor groundwater potential. The overall accuracy of 81.25% with a Kappa coefficient of 0.72 explains good agreement between the reference data and the map. The estimated area under good groundwater potential appears too little concerning the increasing population and urbanization. Therefore, the state government in general and the water resources and planning department in particular need to formulate suitable strategies to combat the water scarcity scenario waiting ahead. The study suggests raising the use of surface water from nearby rivers to lessen the pressure on groundwater resources.

Tradeoffs and Synergies in Tropical Forest Root Traits and Dynamics for Nutrient and Water Acquisition: Field and Modeling Advances

Vegetation processes are fundamentally limited by nutrient and water availability, the uptake of which is mediated by plant roots in terrestrial ecosystems. While tropical forests play a central role in global water, carbon, and nutrient cycling, we know very little about tradeoffs and synergies in root traits that respond to resource scarcity. Tropical trees face a unique set of resource limitations, with rock-derived nutrients and moisture seasonality governing many ecosystem functions, and nutrient versus water availability often separated spatially and temporally. Root traits that characterize biomass, depth distributions, production and phenology, morphology, physiology, chemistry, and symbiotic relationships can be predictive of plants’ capacities to access and acquire nutrients and water, with links to aboveground processes like transpiration, wood productivity, and leaf phenology. In this review, we identify an emerging trend in the literature that tropical fine root biomass and production in surface soils are greatest in infertile or sufficiently moist soils. We also identify interesting paradoxes in tropical forest root responses to changing resources that merit further exploration. For example, specific root length, which typically increases under resource scarcity to expand the volume of soil explored, instead can increase with greater base cation availability, both across natural tropical forest gradients and in fertilization experiments. Also, nutrient additions, rather than reducing mycorrhizal colonization of fine roots as might be expected, increased colonization rates under scenarios of water scarcity in some forests. Efforts to include fine root traits and functions in vegetation models have grown more sophisticated over time, yet there is a disconnect between the emphasis in models characterizing nutrient and water uptake rates and carbon costs versus the emphasis in field experiments on measuring root biomass, production, and morphology in response to changes in resource availability. Closer integration of field and modeling efforts could connect mechanistic investigation of fine-root dynamics to ecosystem-scale understanding of nutrient and water cycling, allowing us to better predict tropical forest-climate feedbacks.

Assessment of roof water harvesting potential of Navsari city of Gujarat State, India by Remote sensing and Geographic information system (GIS)

Due to the water scarcity scenario in many parts of the Navsari city, Gujarat State in India, it is imperative to adopt cost-effective technologies that could harvest rainwater for satisfying drinking water requirements. The study was conducted with the aim of assessing the rainwater harvesting potential of Navsari city using remote sensing and Geographic Information System (GIS). The built-up areas of Navsari that could harness rainwater were identified by remote sensing and GIS. The effective built-up area contributing to rainwater harvesting was found to be 3.37 km2. The classification was carried out using “Remap” to assess the extent of the built-up area. The city was divided into equal grids and classification of each grid was implemented. The ground truth data was used for the evaluation of the built-up area. The roof water harvesting potential was estimated considering the average annual rainfall of 1621 mm and adopting suitable runoff coefficients. The rainwater harvesting potential of roofs for rainfall of different probabilities was estimated. For return periods of 10 years, 25 years, 50 years and 100 years, the roof water harvesting potentials were estimated to be 0.226, 0.261, 0.287 and 0.312 Million Cubic Metres (MCM), respectively. The estimated average roof water harvesting potential of Navsari city was 164 million litres per year, capable of satisfying the drinking water demand of approximately 1.12 lakh people annually. The rainwater harnessed from the rooftop could augment the current water supply and immensely help in fulfilling the drinking water demand of Navsari.

Water dynamics over a Western Patagonian watershed: Land surface changes and human factors

Warming trends in Patagonia and severe droughts in recent decades are still poorly understood in terms of their hydrological effects. The effects of climate change on water dynamics in addition to human water management could generate a future water scarcity scenario in one of the regions with the most abundant water resources of Chile. The aim of this work is to focus on assessing the impacts of warming trends on water dynamics in the Patagonian Simpson River watershed during the last two decades. We estimated anomalies in the main components of water balance such as precipitation (P), snow cover (SC), evapotranspiration (ET) and streamflows (Q) as well as surface variables and meteorological forcing (i.e. air temperature - Ta, solar radiation - RS, land surface temperature - LST). The processed data were obtained from remote sensing, reanalysis and in-situ data. We implemented a trend analysis for each variable in the period 2000-2019 at monthly, seasonal and annual scale. Results showed a warming trend in Ta and LST of about 1.2 °C and 2.1 °C, respectively, concentrated mainly in the autumn and winter seasons. Although P showed non-significant trends, Q diminished significantly at rates of more than 9.1 m3/s/decade, representing 36% of its historical mean. However, the decreases in Q are seen only in the maximum (spring) and minimum (summer) seasonal flows. These decreases are explained by significant increases in ET, led by a positive feedback of its drivers (LST, Ta and RS), which is directly linked to the impact of warming and an associated vegetation greenness in the watershed, as well as a decrease in SC during winter that feeds the Simpson River during spring and summer. The decrease in Q is reinforced by the intensification of water withdrawals in recent decades, as shown by an accelerated increase in water rights for agricultural and drinking uses. In a context of water scarcity and increasing and extreme droughts, this work contributes to further understanding water dynamics in western Patagonia, providing support for policy and decision-making when defining sustainable productive practices at watershed scale.

Estimating the impact of climate change on water levels in a data-poor river basin in southeastern Brazil

Abstract In basins with multiple water uses, it is possible a conflict over water use may occur. This probability increases under a water scarcity scenario. Therefore, it is important to estimate the possible impact of climate change on water availability in this type of basin, to support the decision-making of its users. The Ribeirão do Cipó is an example of a Brazilian watershed susceptible to this situation. Besides having poor hydrological data, it is used for public water supply, electricity generation and recreation. The present work developed a methodology for estimating water availability impacted by climate change, which was particularly applied to this watershed. The methodology consisted of feeding the rainfall–runoff hydrological model called soil moisture accounting procedure with precipitation and evapotranspiration data projected by the Eta-CPTEC regional climate model and nested to three global climate models. The outputs methods were obtained in terms of average monthly flow, for 2010–2039, 2040–2069 and 2070–2099 for the representative concentration pathway (RCP) 4.5 and RCP 8.5 scenarios. Despite the small amount of hydrological data available on the basin, the results were similar to those of the methods used as reference, thus demonstrating that the methodology used can be an alternative in estimating flow for climate change scenarios.