Availability Of Irrigation Water Research Articles

An Incubation Experiment on Screening of Black Gram Varieties for Tolerance to Saline Irrigation Water

Water is a second most important resource in agriculture followed by land. The water availability for irrigation is often scarce, is one of the most critical input for agriculture production in most areas. Productivity in these areas can be enhanced by better management of rainwater and /or development of groundwater. So the present investigation was carried out to study the effect of saline water irrigation on the growth of blackgram. The various treatment included in the study were three ruling varieties of blackgram as factor V viz., V1- VBN 6, V2- VBN 4 and V3- VBN 3 and four salinity levels as factor S viz., S1-EC-3 dS m-1 and Sodium Absorption Ratio (SAR) - 4; S2-EC- 3 dS m-1 and SAR-6; S3-EC-3 dS m-1 and SAR-8; S4-EC-6 dS m-1 and SAR-6. The experiment was laid out in a Factorial Completely Randomized Design (FCRD) with three replications. The results of the study concluded that the soil application of saline water (EC-3 dS m-1 and SAR-4) irrigation to saline tolerant blackgram variety VBN 3 (S1V3) was identified as best treatment combination to realize the maximum germination of blackgram under saline water irrigation.

Estimating uptake and internal transport dynamics of irrigation water in apple trees using deuterium-enriched water

With future climatic scenarios foreseeing increased crop water demands and reduced irrigation water availability, a deeper knowledge on the dynamics of water uptake and translocation inside plants is needed. Little is known about the time interval existing between the irrigation water supply and the presence of irrigation water inside trees, and whether the dripper localization can affect water uptake and translocation dynamics. Another research gap concerns the redistribution of irrigation water in the canopy following irrigation localized to one side of the tree.A field and a pot experiment were designed to gain more insight into this context. In the field experiment, we tested the effect of different drip irrigation layouts on the extent and velocity of water uptake by apple trees. Trees were irrigated using deuterium-enriched water using one, two, or four drippers per tree. Samples were collected from different heights in the canopy at regular intervals following the irrigation event. In the pot experiment, the soil was saturated with labelled water and samples were collected at different time intervals and heights along the tree stem. Labelled water was detected in the lowest stem section of potted trees after 1 h from irrigation. In field-grown trees, labelled water appeared in the shoots after 4 h and 6 h in the bottom and top part of the canopy, respectively. By increasing the number of drippers per tree, the fraction of irrigation water in the shoots increased accordingly. However, uptake and transport velocity were unaffected by the number of drippers, averaging 0.60–0.65 m h-1. In trees that were irrigated from one side only, irrigation water could be found on the opposite side in the top part of the canopy. Our results suggest that the localization and amount of irrigation water can significantly influence root water uptake in apple trees.

Leaf Biochemical and Kernel Metabolite Profiles as Potential Biomarkers of Water Deficit in Walnut (Juglans regia L.) cv. Chandler

Walnut cultivation is expanding into regions where water availability for irrigation is lower than crop evapotranspiration. However, information regarding the responses and adaptations of walnut trees to water deficit remains scarce. In this study, we applied three irrigation levels, 100%, 75%, and 50% of crop evapotranspiration (referred to as T100, T75, and T50, respectively), to Chandler walnut trees over two consecutive seasons. During the second season, we evaluated leaf water-deficit biomarkers, including proline, malondialdehyde, soluble sugars, phenols, and flavonoids, using targeted spectrophotometry. Despite not finding significant differences in biomarker concentrations among the irrigation regimes, we observed variations between different collection times (sprouting, endocarp hardening, and maturity). Furthermore, we assessed the kernel metabolome using untargeted gas chromatography–mass spectrometry, profiling seventy-one metabolites across all samples. Notably, forty-one of these metabolites were identified as members of distinct groups, comprising carbohydrates (n = 11), fatty acids (n = 11), organic acids (n = 9), and amino acids (n = 5). Linear mixed models showed no significant differences between the irrigation regimes. However, in the T50 treatment, multivariate analysis (PCA) revealed a higher concentration of osmotic adjustment metabolites, which are potentially associated with protecting oil biosynthesis under high-temperature and water deficit conditions.

Synergistic management of forest and reservoir infrastructure improves multistakeholders’ benefits across the forest-water-energy-food nexus

Forest management can influence multistakeholders' benefits across the forest-water-energy-food nexus at the watershed scale. However, bringing synergistic gains for multiple stakeholders is still a challenge for regional sustainable management. We took the Changhuajiang basin in China's Hainan Island as a case to present the impacts of synergistic management for upstream forest and reservoir optimization on the benefits of downstream hydropower enterprise and different farmers. By multimodel ensembles and scenario analysis, we quantified the relationships among upstream forest ecosystem management (rubber-intercropped), reservoir, water flow and downstream stakeholders' benefits (i.e., hydropower generation for the energy company, and available irrigation water for two downstream sites' farmers). We also adopted the genetic optimization algorithm to obtain the optimal reservoir infrastructure operation rule for the benefit improvement of multiple stakeholders. We found that rubber-intercropped management significantly increased reservoir inflow in the dry seasons (5%–170%) and reduced it in the rainy seasons (0.5%–7%). The irrigation water availability for downstream farmers in the Gao Canal and downstream irrigation areas correspondingly increased by 7% and 24.3% on average, respectively, with a slight change in hydropower production. Further, we found that water regulation by reservoir optimization operation could enhance the irrigation water supply (36.6–92% and 0–100% in Gao Canal and downstream irrigation areas, respectively) and hydropower generation (14.8–28.4%). This study indicates that the effect of upstream forest management on downstream multistakeholders' benefits could be strengthened by reservoir water flow regulation across the forest-water-energy-food nexus, and demonstrates the key role of infrastructure in regulating ecosystem service flow for strengthening the benefits of multistakeholders in the context of ecosystem management.

Performance of real evapotranspiration products and water yield estimations in Uruguay

Real evapotranspiration (ETR) is a key variable in socio-ecological systems since it is related to the food supply, climate regulation, among others. Additionally, ETR plays a significant role in determining water yield (WY) at the catchment level, which directly impacts water availability for consumption and irrigation. Therefore, it is essential to quantify ETR and WY fluctuations in response to various human pressures to enable comprehensive water planning. In recent decades, remote sensing has become increasingly employed worldwide for hydrological monitoring and estimating ETR. In Uruguay, several approaches have been attempted to quantify ETR. However, there is still a lack of assessments concerning the performance of different products, particularly those using remote sensing. The main objectives of this article were twofold: a) to evaluate the performance of various spatial explicit approaches for estimating real ETR and b) to estimate and analyse the variability in WY derived from the different ETR products for three climatically contrasting years. To achieve these objectives, we utilized four remote sensing ETR products: the Penman–Monteith–Leuning model (PMLv2), the MODIS product, the Simplified Jackson Model based on Landsat images and INTA-SEPA model based on NOAA-AVHRR images. We also employed two water balance models at two scales: national (derived from the National Institute for Agricultural Research of Uruguay, INIA) and micro-watershed level. Our results indicate that MODIS and PMLv2 remote sensing products exhibited better performances compared to the other approaches. These products provided the highest spatial (500 m) and temporal (8 days) resolution, effectively capturing seasonal differences between land-covers. Moreover, they showed positive and strong correlations with annual precipitation and productivity. The discrepancies observed between products have direct implications on the estimation of WY, not only in terms of quantity but also in terms of spatial patterns. Future studies should explore the application of MODIS and PMLv2 ETR estimations for understanding hydrological and ecological processes, conducting climate change research, detecting and mitigating agricultural drought, and managing water resources effectively.

Effectiveness of tomato plant growth with drip irrigation techniques in drylands

Dry land with low rainfall results in minimal availability of irrigation water. However, the lack of irrigation water is not an obstacle in cultivation if the right, effective and efficient irrigation method is applied, namely drip irrigation. This study aims to see the effect of applying drip irrigation techniques with different water discharge treatments on tomato plant growth. This research was conducted in Batu Putik Village, East Lombok Regency from August 12, 2020 to September 20, 2020. This research method uses experimental methods by conducting direct experiments in the field. This study used a Completely Randomized Design (CRD) with 3 treatments 4 times repeated so that 12 experimental units were obtained. Each treatment was P1 with a 90° tap slope discharge, P2 with a 45° tap slope discharge, and P3 with a 15° tap slope discharge. The research data were analyzed using ANOVA. The results of the drip irrigation technique design performance test showed an average uniformity coefficient percentage of 94% in all treatments. The results of this test provide an insignificant effect on plant height, stem diameter, and number of leaves of tomato plants. So this insignificant result shows that the application in the field in relation to water efficiency should use P1 with less water distribution but gives the same effect as P2, and P3 on tomato plant growth. While in wet and dry stems, there is a significant effect between treatments.

Ketersediaan dan Kebutuhan Air Daerah Irigasi Ameroro Kabupaten Konawe

In general, sources of agricultural irrigation in Indonesia still rely on rainwater, so the productivity of wetland agriculture, especially rice, is highly dependent on rainwater as an agricultural input. In this position, irrigation (weirs) is important in maintaining the availability of water for agricultural irrigation needs. This study aims to analyze water availability and water demand from Ameroro Irrigation. Both of these results provide information (pattern) of farmer planting. Research data comes from primary and secondary. Comparative analysis of the supply and demand for irrigation water using the Penman method and the F.J. Mock method to determine the amount of water flow from rainfall data, the hydrological characteristics of the catchment area, and evapotranspiration. The results of this study position that the construction of the Ameroro Dam has a vital role in maintaining the balance of irrigation (inflow and outflow). Maintaining this balance is at the same time the basis for irrigation engineering management efforts for agricultural activities. For farmers, those who live on or cultivate functional agricultural land A, B, and C start the planting season in May or in another month taking into account that the maximum plant growth period does not occur in the October period.

Producer Perceptions on the Value and Availability of Water for Irrigation in the Mississippi Delta

AbstractThe agricultural production in the Mississippi Delta is threatened by the water level declines in the Mississippi River Valley Alluvial Aquifer (MRVAA). This study assesses the growers’ perceptions of the value and availability of water for irrigation based on data collected in a survey in 2012 in the Delta region of Mississippi, USA. The total cooperation rate for this survey was 79.3%. The results showed that 97.39% (448 out of 460) of respondents believed that water is important for farming in the Delta region of the MRVAA. Fifty‐two percent of the survey respondents agreed that the major cause of groundwater depletion is agricultural irrigation water use. More than 50% of the survey respondents believed there is sufficient water in the Delta region, but it is not managed properly. The value of water for irrigation ranged from $463 to $690 per ha for corn (Zea mays L.), $399 to $615 per ha for soybean (Glycine max L.), and $223 to $336 per ha for cotton (Gossypium hirsutum L.). The majority of the respondents considered that there is a need for regulation of water use to protect the aquifer and ensure water availability in the future.

Predictions of land use/land cover change, drivers, and their implications on water availability for irrigation in the Vea catchment, Ghana

Assessment and prediction of land use/land cover change using spatiotemporal data are of great importance for better environmental monitoring, land use planning, and management. Therefore, the objective of this study is to predict LULC change, its driving factors and impact on water availability for irrigation in the Vea catchment, Ghana. CA-Markov model was used to predict land-use changes in 2038 and 2054. Terrset geospatial monitoring and modeling system software was used to run the model. The Relative Importance Index was used to identify major drivers of the LULC change. The results showed an increase in cropland from 181 km2 in 2038 to 183 km2 in 2054 at the expense of grassland and mixed vegetation/forest, which are expected to decrease from 51–50 km2 and 73–71 km2, respectively. Population growth and agricultural expansion are among the leading drivers of LULC change in the Vea catchment. The CA-Markov model shows a continued increase in anthropogenic land uses, negatively affecting irrigation water availability and landscape sustainability. These results provide a foundation for sustainable land use governance through responsible planning and management of land and water resources by considering trade-offs between LULC change and water availability for irrigation in the Vea catchment.

Taking advantage of water scarcity? Concentration of agricultural land and the politics behind water governance in Chile

Chile is currently facing a major drought that has caused several problems, most of them concentrated in terms of the availability of water for both human consumption and irrigation for agriculture. Under such conditions, the main instrument the government has at hand to assign water for agricultural use is the Water Scarcity Decree (WSD), which, among other aspects, allows for the extraction of underground water. However, this practice requires an important investment from the agricultural producer, making it only affordable by relatively larger producers. Therefore, under the current climatic conditions and a generalized lack of water, larger agricultural producers are the ones who benefit the most from the establishment of a WSD and thus have the incentives to use their political power to pressure for its issuing. Whereas conventional wisdom suggest that this is indeed the case, there is no previous evidence trying to link the size of agricultural exploitations and the likelihood of the establishment of a WSD. In the paper we use the share of large exploitations at the municipality level, as a measure that can proxy for local political power, and the establishment, the number, and duration of WSD within any given year. Consistent with the hypothesis, our results show that areas dominated by larger producers/exploitations are more likely to be declared as water scarce, to have more decrees in a year, and to have them in place for longer periods of time, even after controlling for socioeconomic characteristics and climatic conditions, such as precipitations and water flow.

Comparative Analysis of Growth and Physiological Responses of Sugarcane Elite Genotypes to Water Stress and Sandy Loam Soils.

Stumpy irrigation water availability is extremely important for sugarcane production in Pakistan today. This issue is rising inversely to river flow due to inadequate water distribution and an uneven rainfall pattern. Sugarcane growth faces a shortage of available water for plant uptake due to the low water-holding capacity of sandy loam soil, particularly under conventional flood irrigation methods. To address this problem, sugarcane clones were evaluated for their agronomic and physiological traits under conditions of low water availability in sandy loam soil. Ten cane genotypes, HSF-240, SPF-213, CPF-249, CP 77-400, S2008-FD-19, S2006-US-469, S2007-AUS-384, S2003-US-633, S2003-US-127, and S2006-US-658, were exposed to four levels of water deficit created through skip irrigations. These deficit levels occurred during the 9th, 11th, 13th, and 16th irrigations at alternate deficit levels between 2020 and 2022. Physiological data were collected during the tillering and grand growth stages (elongation) in response to the water deficit. The sugarcane clones S2006-US-658, S2007-AUS-384, and HSF-240 exhibited resistance to low water availability at both the tillering and grand growth stages. Following them, genotypes S2006-US-658, S2007-AUS-384, and HSF-240 performed better and were also found to be statistically significant. Clones susceptible to water deficit in terms of growth and development were identified as CP 77-400, S2008-FD-19, S2006-US-469, and S2003-US-633. These genotypes showed reduced photosynthetic rate, transpiration rate, stomatal conductance, relative water content, cane yield, and proline content under stressed conditions. Therefore, genotypes S2006-US-658, S2007-AUS-384, and HSF-240 were better performers concerning physiological traits under water deficit and sandy loam soil in both years. Moreover, a significant positive correlation was assessed between agronomic traits and photosynthetic rats. This study highlights that sugarcane can sustain its growth and development even with less irrigation frequency or moisture availability, albeit with certain specific variations.

A Review on Understanding the Effects and Mechanisms of Salinity Tolerance in Rice (Oryza sativa L.)

Salinity, along with drought, is one of the key abiotic stressors that has posed a danger to the advancement and evolution of cereal crops like rice and wheat. Water shortage and a lack of irrigation water availability are the main causes of salty soil formation. Rice is salt sensitive and glycophyte, wheat is moderately salt tolerant. Wild tolerant cultivars like Oryza coarctata and Oryza alta are more tolerant than traditional cultivars such as Pokkali and Nona Bokra in rice. Salt stress affects crop plants’ processes like ionic imbalance, osmotic and oxidative stress. Na+ should be low in the shoots of the plant which is restricted by various transporters in the cell membrane of the roots in soil. High K+ & Na+/K+ homeostasis should be maintained. Many RILs and NILs have been developed which acts as a donor for salinity tolerant genes. FL478 is a recombinant inbred line in which candidate genes are situated in the Saltol region of chromosome 1 region which is obtained by a cross between Pokkali x IR29. Increase in world’s population, rice output must be increased by at least 25% by 2030 and 50% by 2050.Salinity stress is a polygenic character which involves several genes works in harmony. For evolution of salinity tolerant cultivars, we need to access the physiological, biochemical genetic responses of the crop plant which helps in transfer of candidate genes from donor parents to elite high yielding salt sensitive cultivars. Especially in rice salt tolerant mechanisms like, Ion equilibrium regulation, Adjustment of osmotic potential, Reduction of ROS, Nutrient disequilibrium, and Regulation of PGRs. Conventional, MABC, MAS and direct gene transfer by transgenic methods. This review paper's main objective is to understand the mechanisms of the crop plants to salinity effects and development of salt tolerant cultivars by modern approaches which fulfill the food scarcity of staple food crops with increasing population.

Impacts of climate change on vegetable production and ways to overcome them

Vegetables play a key role in food security and nutrition as the food system shifts from food quantity to dietary quality and health benefits. One of the main reasons for the low production and declining average yields of most vegetable crops is climate change. Important limiting factors in maintaining and increasing vegetable crop yields are rising temperatures, reduced water availability for irrigation, flooding and salinity. Under changing climatic conditions, crop failures, declining quality and increasing pest and disease problems are becoming commonplace and making vegetable production unprofitable. Since many physiological processes and enzyme activity are temperature dependent, they will be greatly affected. Drought and salinity are two important effects of rising temperatures that reduce vegetable crop yields. These impacts of climate change also affect the emergence of pests and diseases, host-pathogen interactions, distribution and ecology of insects, timing of emergence, migration to new locations, and their ability to overwinter, all of which become a major barrier to vegetable production. To mitigate the adverse effects of climate change on the productivity and quality of vegetable crops, sound adaptation strategies need to be developed. Emphasis should be placed on the development of production systems that improve water efficiency and are adapted to hot and dry conditions. Technological practices, such as mulching with crop residues and plastic materials, help maintain soil moisture. Excessive soil moisture due to heavy rains becomes a serious problem that can be solved by growing crops in raised beds. An effective way to solve these problems is to create genotypes that are resistant to high temperatures, moisture, salinity and resistance to climatic conditions, using traditional and non-traditional breeding methods, genomics, biotechnology, etc.

OPTIMIZATION OF WATER RESOURCES UTILIZATION DISTRIBUTION FOR AGRICULTURAL BENEFITS IN THE CLAMPIS IRRIGATION AREA SAMPANG DISTRICT

Utilization of water resources and management is an important factor and has a decisive role in order to increase production per plant in general and crop production in particular. In order to maintain self-sufficiency in food, it is necessary to make efforts to continuously increase the intensity of potential food crops. These efforts include optimizing the proper distribution of water utilization. Factors to determine the need for irrigation water include land preparation, consumptive use, percolation and seepage, replacement of water layers, and effective rainfall. While the method used in this study is optimization using a linear program using the Solver facility in Microsoft Excel with the aim of optimizing the availability of irrigation water so as to produce maximum profits and distribution of irrigation utilization that is more effective and efficient. From the optimization results using the Solver and Microsoft Excel tools, it can be seen that the maximum area of ​​land that can be planted with the available inflow at the intake for MTI (Rice I 2086 Ha/Tobacco II 667.54 Ha), MT-II (Rice I 667, 54 Ha/Tobacco I 1391 Ha/PolowijoI 567.35 Ha/Rice II 128.11 Ha), MT III (Polowijo I 323.65 Ha/Rice II 348.89 Ha/Tobacco II 1261.46 Ha/Polowijo II 825, 00) and provides an analysis of the maximum profit of agricultural products of Rp. 178,183,800,000.00,-. Keywords: Linear Program Optimization; Utilization of Water Resources; Agricultural Benefits; Klampis Irrigation.

Land suitability analysis using a multicriteria decision‐making approach for optimal irrigation in a medium irrigation scheme in West Bengal, India

AbstractThe present study aspires to distinguish suitable irrigation lands using the analytical hierarchy process (AHP) and geographic information system (GIS) of the Shali River basin area, which is a part of the Shali reservoir irrigation project (medium irrigation project) of West Bengal, India. Therefore, 12 factors were identified as criteria, including elevation, slope, rainfall, soil group, sand, silt, clay, nitrogen, pH, organic carbon, land use and land cover (LULC) and river distance. The results show that the Shali Basin has approximately 64% irrigation‐suitable land. The irrigational suitability reveals that the villages near the river have highly irrigation‐suitable lands. Therefore, it can be said that the distance to the river plays a major role as it determines the irrigation water availability. It is therefore advisable to install rainwater catchment structures in villages that are significantly distant from the river. This study may help farmers to select cropping patterns according to irrigation suitability and the concerned readers to understand the irrigation land suitability analysis with appropriate parameters and methods under any medium irrigation project.

Physiological and Canopy Temperature Responses to Drought of Four Penstemon Species

Available water for urban landscape irrigation is likely to become more limited because of inadequate precipitation and the ever-increasing water demand of a growing population. Recent droughts in the western United States have also increased the demand for low-water-use landscapes in urban areas. Penstemon species (beardtongues) are ornamental perennials commonly grown in low-water-use landscapes, but their drought tolerance has not been widely investigated. The objectives of this study were to determine the effects of water availability on the morphology, physiology, and canopy temperature of Penstemon barbatus (Cav.) Roth ‘Novapenblu’ (Rock Candy Blue® penstemon), P. digitalis Nutt. ex Sims ‘TNPENDB’ (Dakota™ Burgundy beardtongue), P. ×mexicali Mitch. ‘P007S’ (Pikes Peak Purple® penstemon), and P. strictus Benth. (Rocky Mountain penstemon). Twenty-four plants of each penstemon species were randomly assigned to blocks in an automated irrigation system, and the substrate volumetric water content was maintained at 0.15 or 0.35 m3⋅m−3 for 50 days. The decreased substrate volumetric water content resulted in a decreased aesthetic appearance of the four penstemon species because of the increased numbers of visibly wilted leaves and chlorosis. Plant growth index [(height + (width 1 + width 2)/2)/2], shoot number, shoot dry weight, leaf size, and total leaf area also decreased as the substrate volumetric water content decreased, but the root-to-shoot ratio and leaf thickness increased. Photosynthesis decreased, stomatal resistance increased, and warmer canopy temperatures were observed when plants were dehydrated. Additionally, as substrate volumetric water content decreased, the leaf reflectance of P. barbatus and P. strictus increased. Penstemon digitalis, which had the highest canopy–air temperature difference, was sensitive to drought stress, exhibiting a large proportion of visibly wilted leaves. Penstemon ×mexicali, which had the lowest root-to-shoot ratio, had the lowest shoot water content of the species studied and more than 65% of leaves visibly wilted when experiencing drought stress. Penstemon barbatus and P. strictus, native to arid regions, exhibited lower canopy–air temperature differences and better aesthetic quality than the other two species. Under the conditions of this study, Penstemon barbatus and P. strictus exhibited better drought tolerance than P. digitalis and P. ×mexicali.

Deficit irrigation effects on adjunct and all‐malt barley yield and quality

AbstractSemiarid regions are reliant on irrigation to produce large‐yielding and high‐quality malt barley (Hordeum vulgare L.). Drought in the western United States is of concern as surface and ground water reductions are occurring that affect irrigation water availability. Implementing a seasonal water deficit compared to evapotranspiration (ET) is a potential strategy to reduce water usage if yield and quality can be maintained. Research was conducted in Aberdeen, ID, on the effects of deficit irrigation on yield, grain quality, and malt characteristics. Five genotypes were selected to represent those used for large‐scale adjunct brewing and those targeted at the all‐malt craft industry. Irrigation was managed at three rates (100%, 75%, and 50%) of estimated crop evapotranspiration (ETc) using sprinkler irrigation. Total aboveground dry matter was not affected by irrigation until soft dough (Feekes 11.2). Yield was similar within a genotype with irrigation reduction from 100% ETc to 75% ETc. Averaged across genotypes, yields were 6936 kg ha−1 at 100% ETc and 6297 kg ha−1 at 75% ETc. At 75% ETc, protein remained just below the adjunct target (130 g kg−1) for four of five genotypes while all five exceeded the all‐malt target (120 g kg−1). Reduced irrigation decreased malt extract and increased diastatic power, where β‐glucan either did not differ or increased. Deficit irrigation is promising, particularly for adjunct brewing; however, expected changes to malting quality must be understood and genotype selection, altered fertilizer management, and/or changes to malting criteria may be needed for implementation.

Effect of deficit irrigation on the growth and yield of peanuts (Arachis hypogaea (L.) Merr.) compared to AquaCrop model simulation

The availability of irrigation water during the growing season reflects on the potential yield at the end of the peanuts’ growing season. Monitoring water availability is essential to optimize production. This study aimed to identify the effect of irrigation water on peanuts (Arachis hypogaea (L.) Merr.) under various irrigation conditions between actual and simulated AquaCrop. The research was conducted in the experimental field utilizing four irrigation treatments which were 60%, 80%, 100% of field capacity (FC), and standard irrigation. The correlation results between the actual and simulated ones showed that the R2 value was 0.974–0.990 for the canopy cover parameter, 0.026–0.534 for ETc, and 0.542-0.554 for production. Comparison between actual and simulated AquaCrop showed Root Mean Square Error (RMSE) values of 5.08–­­9.74 for canopy cover parameters, 1.11–3.12 for ETc, and 0.82–1.09 for production. Welch test statistical analysis indicated values of 2.31–5.52 for plant biomass and 0.04–3.98 for dry pod yields. The AquaCrop simulation accurately predicted canopy cover at 80% irrigation treatment compared to 60%, 100%, and standard irrigation treatments. Parameter of ETc in AquaCrop simulations showed inaccurate predictions for biomass production and pod dry weight when compared with actual results on all irrigation treatments.

Technical and Economic Irrigation Potentials Within Land and Water Boundaries

AbstractTo satisfy the increasing global demand for agricultural products, the expansion of irrigation is an important intensification measure. At the same time, unsustainable water abstractions and cropland expansion pose a threat to biodiversity and ecosystem functioning. Irrigation potentials are influenced by local biophysical irrigation water availability and competition of different water users. Using a novel hydro‐economic data processing routine that considers economic criteria of water allocation via a productivity ranking of grid cells and both land and water sustainability criteria, we estimate global irrigation potentials at a 0.5° spatial resolution. We show that there is considerable technical potential to expand irrigation within local water and land boundaries. In terms of potentially irrigated areas on all global land suitable for crop production, 2,144 Mha could be irrigated within land and water environmental boundaries when only considering biophysical criteria. However, not all of these areas would actually be irrigated under consideration of irrigation costs. Of these, only 698 Mha (330 Mha) have a yield gain of more than 300 (600) USD ha−1 under the current crop mix valued at their current commodity price (economic irrigation potential).

Growth, Solute Accumulation, and Ion Distribution in Sweet Sorghum under Salt and Drought Stresses in a Brazilian Potiguar Semiarid Area

Agriculture in semiarid regions commonly face problems because of salt and availability of irrigation water. Considering this, studies on cultures resistant to salt and water stresses involving sweet sorghum are required. Therefore, the aim was to evaluate the growth and other mechanisms of tolerance to salinity and water deficit in BRS 506 sweet sorghum. The experimental design was conducted in Upanema-RN, Brazil, in randomized blocks, where the isolated and interactive effect of 3 salinity levels, expressed as the electrical conductivity of irrigation water (1.5, 3.8, and 6.0 dS m−1), and 3 irrigation depths (55, 83, and 110% of crop evapotranspiration) were evaluated. During the cycle, sorghum adapted to the salinity and deficit irrigation depth, since stem height reduced only −5.5% with increasing salinity and −11.95% with decreasing irrigation depth, and aerial dry mass was affected by interaction only at the end of the cycle. Proline, total amino acids, and total soluble sugars were not differenced by stresses. Additionally, around 68.71% of total Na+ was at roots at the end of the cycle. In summary, sorghum BRS 506 was more tolerant to salt than water stress and used Na+ compartmentalization in root cells as the main tolerance mechanism.