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Almond and pistachio are socio-economically significant tree crops grown in California’s San Joaquin Valley (SJV). Continuing commercial production with efficient irrigation planning under changing climate requires an extensive understanding of their biophysical interactions such as altered phenology, biomass accumulation, transpiration, and other processes. This study examines the phenology and water use (ETc) responses of almonds and pistachios under two scenarios: climate change (warming-only) and climate change with elevated atmospheric CO2 (eCO2), using an agrohydrological model, VIC-CropSyst. The model was calibrated and validated using observations on crop evapotranspiration. The simulated crop responses to warming-only and eCO2 revealed compounding effects on chill accumulation, phenology, biomass accumulation, and eventually on crop water use. The active growth period from bud break to dormancy was prolonged by 10–25 days for both crops under simulated Representative Concentration Pathways (RCP4.5 and RCP8.5) scenarios compared to the baseline. The annual ETc under warming-only scenarios showed a slight increase for almonds (1 % under RCP4.5 and 3 % under RCP8.5) and a higher increase for pistachios (8 % under both RCP4.5 and RCP8.5) by the mid-21st century. These increases in ETc translate to 260 (almonds) and 180 (pistachios) million m3/year of additional water for irrigation in the absence of eCO2 effects. The eCO2 is expected to moderately reduce irrigation demand by 35 million m3/year for almonds and increase by 140 million m3/year for pistachios over the baseline. The outcomes can guide decision-makers to anticipate potential threats and concoct adaptive strategies by managing irrigation and choosing suitable cultivars or alternate crops.

During the agronomic design of micro-sprinkling systems, it is difficult to guarantee the wetting of a volume of roots that allows the appropriate extraction of water and nutrients, as well as adequate anchorage. This leads to extreme precision at this stage, essentially in the estimation of crop coefficients KC, irrigation location coefficient KL and climatic variability coefficient KVC, as well as leaching requirements LR. When these are not estimated in a rigorous manner, the results can affect irrigation efficiency and the profitability of the installation. Identifying the effects of simplifications made during agronomic design on the accuracy of the capability's operating parameters is one of the ways to contribute to agricultural food production, considering the rational and efficient use of water. The research used the design procedure proposed by Keller and Rodrigo/1979, and the hypothetical-deductive method was also used to evaluate the effects of simplifications in the operating parameters of the installation. As a result, arguments were obtained that allow establishing the effects of simplifications in the rigor of the results of the agronomic design of localized irrigation systems, which allow us to conclude that the rigorous agronomic design of localized irrigation systems with micro-sprinkling leads to establishing effective installations. [ABSTRACT FROM AUTHOR]

Drought is a major threat in agriculture and horticulture, including commercial strawberry production. Here, we compare hormonal regulation of a first-line drought stress response, namely stomatal closure, in two Fragaria x ananassa cultivars, known to differ in their drought stress phenotype. We show that the observed difference in xylem abscisic acid accumulation cannot explain the different stomatal responses under osmotic stress. Foliar abscisic acid accumulation cannot fully account for the stomatal behavior in one of both cultivars either. An indirect effect of abscisic acid on stomatal conductance via an impact on leaf hydraulic conductance, possibly mediated via aquaporins, as is recently proposed in literature, was not observed here. Next, we show that these two cultivars respond differently to jasmonic acid and one of its precursors. This difference in sensitivity of the jasmonates pathway between both cultivars may partly explain the different stomatal response. This study contributes to the understanding of the regulation of an important drought stress response in an economically important crop prone to water deficit stress. • Two strawberry cultivars have different g s responses under osmotic stress. • Different xylem ABA accumulation cannot fully explain different g s responses. • Foliar ABA accumulation cannot fully account for different g s responses either. • An indirect effect of ABA on g s , via hydraulic conductance changes is not observed. • Sensitivity of g s to jasmonates is different in both cultivars. [ABSTRACT FROM AUTHOR]

The present field study was conducted to study the effect of long-term poor quality irrigation water and crop residue incorporation on phosphorus (P) content in grain and straw in a rice-wheat cropping system. The long-term experiment had 16 treatment combinations involving four irrigation water qualities: canal water irrigation (SW1), sodic water (SW2), sodic water plus gypsum (SW3) and saline water (SW4) and four crop residue treatments: 6 t wheat straw ha-1 to rice (T1), 6 t rice straw ha-1 to wheat (T2), rice straw to wheat and wheat straw to rice at 6 t ha-1 each (T3) and the unamended control (T4). Irrigation water and crop residue treatments significantly influenced P concentration of grain and straw of wheat as well as rice. Mean value of P content was observed to be the highest under good quality water treatment (SW1) and the least under saline water treatment. Mean P content in wheat grain and straw were in the order of T3 > T2 > T1 >T4. Maximum Cl-1 and HCO3-1 contents were observed in saline water treatment that had not received any crop residue amendment (SW4T4) whereas the lowest values of these ions were found in soil treated with good quality water and both rice and wheat straw amendment (SW1T3) in subsequent seasons. The study showed that adverse effect of poor quality irrigation waters on plant uptake of major nutrients can be managed by incorporating crop residues. [ABSTRACT FROM AUTHOR]

Feeding a growing population with global natural-resource constraints becomes an increasingly challenging task. Changing spatial cropping patterns could contribute to sustaining crop production and mitigating water scarcity. Previous studies on water saving through international food trade focussed either on comparing water productivities among food-trading countries or on analysing food trade in relation to national water endowments. Here, we consider, for the first time, how both differences in national average water productivities and water endowments can be considered to analyse comparative advantages of countries for different types of crop production. A linear-optimization algorithm is used to find modifications in global cropping patterns that reduce national blue water scarcity in the world's most severely water-scarce countries, while keeping global production of each crop unchanged and preventing any increase in total irrigated or rainfed harvested areas in each country. The results are used to assess national comparative advantages and disadvantages for different crops. Even when allowing a maximum expansion of the irrigated or rainfed harvested area per crop per country of only 10 %, the blue water scarcity in the world's most water-scarce countries can be greatly reduced. In this case, we could achieve a reduction of the global blue water footprint of crop production of 21 % and a decrease of the global total harvested and irrigated areas of 2 % and 10 % respectively. Shifts in rainfed areas have a dominant share in reducing the blue water footprint of crop production. [ABSTRACT FROM AUTHOR]

Rice is one of the world's most popular food crops. Since its production is dependent on intensive water use, water management is critical to ensure sustainability of water resource. However, very limited data is available on water use in rice irrigation. In the present study, traditional machine learning methods have been used to predict the irrigation schedule of rice daily. The data of year 2013-2015 is used to train the models and to further optimise it. The data of 2016-2017 is used for testing the models. Correlation thresholds are used for feature selection which helps in reducing the number of input parameters from the initial 26 to final 11. The models estimated the crop water demand as a function of weather parameters. Results show that Adaboost performed consistently well with an average accuracy of 71% as compared to other models for predicting the irrigation schedule. [ABSTRACT FROM AUTHOR]

Water for irrigation constitutes the highest freshwater demand in any country. For a monsoon-fed country like India, variations in precipitation lead to severe repercussions in the agricultural economy. Water security in India has historically been approached by creating more storage capacity and increasing the supply. Can managing the demand for water be an approach to the challenge of water security? What could be the basis for managing the demand? This article revisits the concepts of virtual water flow and water footprint, to examine their applicability in today's context. The present author has applied the concepts in a dip-stick manner on fruit and sugar export from Maharashtra, India. The quantity of water flowing out of Maharashtra from such exports was assessed. The results show a remarkable quantity of scarce water being diverted to foreign lands. This article also discusses the use of these concepts in water policies to nudge the farmers into making choices appropriate for the region. [ABSTRACT FROM AUTHOR]

Alfalfa (Medicago sativa L.) can enhance the supply of nutritious forage when interseeded into semiarid native grassland. Alfalfa is a high water‐using species; therefore, a possible trade‐off between soil water depletion and nutritive value merits study. We determined the effects of interseeding three alfalfa cultivars at two densities on crude protein (CP) and digestible organic matter (DOM) accumulations, the water footprint (WF, m3 evapotranspiration kg−1) of CP and DOM accumulation at two row spacings, and the marginal cost (MC) of such trade‐offs. Nutritive values and accumulation of CP and DOM for mixtures with alfalfa planted at 36‐ or 71‐cm row spacing did not differ in 2018 (P >.05), as both spacings reduced the WF over grass only (P <.0001). Alfalfa presence reduced the WF (P <.001) with respect to CP and DOM accumulation from 20.17 and 3.07 m3 kg−1 in the grass‐only control to 10.14 and 2.22 m3 kg−1 in alfalfa–grass mixtures, respectively. Interseeding alfalfa in wide rows had 23 and 26% less MC of revenue increment than interseeding in narrow rows, relative to grass only in Years 2 and 3, respectively (P <.01). Hay‐type cultivars NuMex Bill Melton and WL 440HQ enhanced the forage mixture nutritive value more than the grazing‐type Falcata–Rhizoma blend, mainly driven by greater alfalfa growth. Interseeding alfalfa into native grasses in wide rows can increase the efficiency of water use (lower WF) by enhancing forage nutritive value at low MC, thereby inducing a minimal trade‐off in soil water consumption. [ABSTRACT FROM AUTHOR]

Across South Africa, the timing of wet-season rainfall within the summer-, winter- and year-round rainfall zones (SRZ, WRZ and YRZ) influences activities including crop production and water resource management. While numerous start- and end-date definitions exist to classify the wet season, most rely on threshold values specified for local-scale application. Focusing on large-scale application, we critically apply an objective and consistent methodology, defining wet-season start and end dates at 10% and 90% of cumulative annual rainfall, using daily rainfall data spanning 1987–2016 for 46 South African weather stations. SRZ, WRZ or YRZ conditions are successfully quantified across all locations. The longest mean SRZ wet season spanned 223 days from 8 September to 18 April at East London Wo (ELW), along the southeast coast. Robertson (ROB), within the south-western region, had the longest mean WRZ wet season of 244 days from 9 March to 7 November. Nearby, Riversdale (RIV) had the longest mean YRZ wet season of 270 days from 17 February to 13 November. Consistency with literature regarding rainfall drivers, start and end dates and the spatial distribution of rainfall seasonality, confirms utility of this metric across South Africa. Therefore, it facilitates comparable rainfall seasonality investigations across regions, including the arid western coast and the southern coast YRZ, where previous methods lack utility, and the calculation of trends in seasonality changes across the country. While for most locations trends are not statistically significant, this method enables further monitoring. [ABSTRACT FROM AUTHOR]

A study was conducted to develop optimal irrigation schedules and crop water production function for cassava in the three major growing areas of India, viz., Salem (Tamil Nadu), Thiruvananthapuram (Kerala), and West Godavari (Andhra Pradesh). The irrigation schedules and water requirements were simulated using CROPWAT, and the model result was verified with field values in Thiruvananthapuram, one of the study areas. The results indicated the wider applicability of CROPWAT in calculating water requirement as well as developing irrigation schedules for cassava irrespective of the agro-climatic conditions. The optimal gross irrigation requirement simulated by CROPWAT was 362, 610, and 703 mm in Thiruvananthapuram, West Godavari, and Salem, respectively, based on the soil, crop and climatic parameters. The optimal schedules were also developed in the study locations using CROPWAT, and it can be used for further irrigation practices and plans to maximize water productivity. Also, the field experimental data in Thiruvananthapuram showed a quadratic relation between crop water requirement and yield (R2 = 0.86). The derived crop water production function (CWPF), yield = - 0.0013 ET c 2 + 1.138 ET c - 203.03 provided yield of 39 × 103 kg ha−1 of cassava corresponding to the simulated gross irrigation requirement of 362 mm in Thiruvananthapuram. Thus the CWPF together with the optimal schedules is a useful tool for water managers and farmers to develop appropriate irrigation plans in advance to mitigate the water scarcity as the result of climate change. [ABSTRACT FROM AUTHOR]

Granular application of potassium (K) in soils testing high is generally not recommended. However, the effect of foliar K on rainfed wheat (Triticum aestivum L.) under these soil conditions is largely unknown. The objective of this work was to identify the effect of K fertilizer on K use efficiency (KUE), grain yield and yield components of wheat. The data were collected until 2017 in an ongoing trial established in 2007 with eight treatments; two granular K rates (0 and 50 kg K ha−1); two foliar N rates (0 and 3 kg N ha−1); and two foliar K rates (0 and 3 kg K ha−1) in a split-split plot arrangement. Treatments were applied to the same plots each season. Treatment with foliar K resulted in the highest KUE response but the effect size varied according to the accumulated precipitation during the reproductive stage. On average, KUE was enhanced in crop seasons with water constrains (<179 mm) during the growth period but the converse was true as the amount of precipitation increased. In contrast, granular K had no effect on KUE irrespective of precipitation conditions. Application of foliar K increased grain yield as compared to granular K from 2988 to 3089 kg ha−1. This enhancement was attributed to an increased number of grains per head. Therefore, foliar K application to wheat is suitable in a soil testing high K to enhance KUE and grain yield, overall in crop seasons with water constrains. [ABSTRACT FROM AUTHOR]

Crop water use efficiency (WUE) has come into sharp focus as population growth and climate change place increasing strain on the water used in cropping. Rainfed crops are being challenged by an upward trend in evaporative demand as average temperatures rise and, in many regions, there is an increased irregularity and a downward trend in rainfall. In addition, irrigated cropping faces declining water availability and increased competition from other users. Crop WUE would be improved by, first, ensuring that as much water as possible is actually transpired by the crop rather than being wasted. Deeper roots and greater early crop vigour are two traits that should help achieve this. Crop WUE would also be improved by achieving greater biomass per unit water transpired. A host of traits has been proposed to address this outcome. Restricting crop transpiration through lower stomatal conductance is assessed as having limited utility compared with traits that improve carbon gain, such as enhancements to photosynthetic biochemistry and responsiveness, or greater mesophyll conductance. Ultimately, the most useful outcomes for improved crop WUE will probably be achieved by combining traits to achieve synergistic benefit. The potential utility of trait combinations is supported by the results of crop simulation modelling. [ABSTRACT FROM AUTHOR]

Winter precipitation is the second largest contributor to the water economy of Pakistan. This precipitation contributes to catering the peak crop water demands in winter as well as the early summer. The present study delineates statistical aspects of winter (December–March) precipitation climatology, its variability and extremes during 1951–2010 in Pakistan. Grading severity criterion was developed to determine the large precipitation deficit (dry) and surplus (wet) cases during winter months/season. The jet stream (JS) and associated dynamical processes were also examined to compare both dry and wet cases. The position, strength and migration of JS are observed in six latitudinal bands (LBs). The correlation analysis of wind speed in LB3 and LB6 with precipitation in Pakistan indicates significant positive and negative relationships, respectively. Zonal wind index (ZWI) derived from wind speed in these LBs consistently exceed (go below) its climatology during asymmetric winters. The analysis shows a strong burst of westerlies and deep vertically integrated moisture flux convergence (VIMT) over the Arabian Sea and along the Himalaya mountains. Mid-level ascent with upper-level wind divergence aggravated moisture in convective centers of Pakistan in wet cases. The northward shifting of westerly (LB5–LB6) and replacement by pronounced easterly (LB2–LB4) winds blocked moisture supply from the Arabian Sea during dry cases. [ABSTRACT FROM AUTHOR]

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BACKGROUND: Water productivity improvement is fundamental to agricultural water use control, and the water footprint provides a new and comprehensive method for identifying the crop‐water relationship. This study is intended to explore the spatiotemporal pattern and driving forces underlying the rice water footprint productivity (WFP) in China during the years 1996–2015 based on calculations of the provincial blue, green, gray, and white water footprints. RESULTS: The national water footprint in paddy rice cultivation was 240.97 Gm3, and green water accounted for 43.9% of the total. The WFP was 0.795 kg m−3 and increased over time in all 30 provinces for which it was calculated. The growth rate in the northern provinces was greater than that in the southern part of the country. The WFP clustered geographically in all years observed. High‐value provinces were concentrated to the south of the Yangtze River, whereas most of the provinces that showed a low WFP were distributed in the north China and northwest subregions. Precipitation and sunshine hours were the most obvious driving factors of rice WFP. The effects of agricultural input, e.g., agricultural machinery power, pesticides, and irrigation efficiency, on WFP also could not be ignored. CONCLUSION: The WFP is a comprehensive and useful index of the crop‐water relationship and water‐use efficiency. Improving agricultural input and irrigation technology are reliable approaches for WFP promotion. Areas in northeast China showed the most urgent need for improving the rice WFP, and the inclusion of the main grain producing areas in the Yangtze River Basin will further reduce ineffective water occupancy to improve water‐use efficiency. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The water extracts of allelopathic crops have potential to stimulate the plant growth when applied at low concentration. Most of the previous studies have evaluated the role of exogenous application of allelopathic water extracts at low fertilizer inputs. In this 2-year study, comprised of three independent field experiments, we evaluated the role of exogenous application of allelopathic water extracts of sorghum/sunflower and benzyl aminopurine, applied alone or in combination, in improving the productivity and profitability of bread wheat grown at optimum and high levels of inorganic fertilizers. In first two studies, the sorghum or the sunflower water extracts (5% each) and benzyl aminopurine were applied alone or in combination with benzyl amino purine under optimal (N:P = 125:90 kg ha−1) and high (N:P = 225:150 kg ha−1) fertilizer; no extract application and water spray were taken as control. In the third study, the sorghum water extracts and benzyl aminopurine were used alone or in combination, under optimal (N:P = 125:90 kg ha−1), high (N:P = 225:150 kg ha−1) and very high (N:P = 325:210 kg ha−1) fertilizer keeping water spray as control. The foliage sprays were done at 40 and 75 days after sowing in all experiments. The results indicated that stay green character, grain yield and yield components, and the profitability of wheat were improved with the exogenous application of sorghum/sunflower water extracts and benzyl aminopurine as compared with the control treatments in all experiments. This improvement can be attributed to enhanced physiological functioning and hermetic response of the crop plants to potential allelochemicals present in crop water extracts. The combine application of water extracts and benzyl aminopurine was most useful in terms of yield increment regardless of any fertility status, possibly due to synergistic action of the allelochemicals and the commercial growth regulator. In nutshell, combine use of allelopathic crop water extracts and benzyl aminopurine can be used to improve wheat yield under any fertility status. However, the application of allelopathic crop water extracts and benzyl aminopurine, either alone or in combination was not profitable when applied at high or very high fertilizer level. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering (17264073) is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Future crop production will be affected by climatic changes. In several regions, the projected changes in total rainfall and seasonal rainfall patterns will lead to lower soil water storage (SWS), which in turn affects crop water uptake, crop yield, water use efficiency (WUE), grain quality and groundwater recharge. Effects of climate change on those variables depend on the soil properties and were often estimated based on model simulations. The objective of this study was to investigate the response of key variables in four different soils and for two different climates in Germany with a different aridity index (AI): 1.09 for the wetter (range: 0.82 to 1.29) and 1.57 for the drier (range: 1.19 to 1.77) climate. This is done by using high-precision weighable lysimeters. According to a "space-for-time" (SFT) concept, intact soil monoliths that were moved to sites with contrasting climatic conditions have been monitored from April 2011 until December 2017. Evapotranspiration (ET) was lower for the same soil under the relatively drier climate, whereas crop yield was significantly higher, without affecting grain quality. Especially "non-productive" water losses (evapotranspiration out of the main growing period) were lower, which led to a more efficient crop water use in the drier climate. A characteristic decrease of the SWS for soils with a finer texture was observed after a longer drought period under a drier climate. The reduced SWS after the drought remained until the end of the observation period which demonstrates carry-over of drought from one growing season to another and the overall long-term effects of single drought events. In the relatively drier climate, water flow at the soil profile bottom showed a small net upward flux over the entire monitoring period as compared to downward fluxes (groundwater recharge) or drainage in the relatively wetter climate and larger recharge rates in the coarser- as compared to finer-textured soils. The large variability of recharge from year to year and the long-lasting effects of drought periods on the SWS imply that long-term monitoring of soil water balance components is necessary to obtain representative estimates. Results confirmed a more efficient crop water use under less-plant-available soil moisture conditions. Long-term effects of changing climatic conditions on the SWS and ecosystem productivity should be considered when trying to develop adaptation strategies in the agricultural sector. [ABSTRACT FROM AUTHOR]

The present study was conducted during the Rabi seasons of 2016–2017 and 2017–2018 to investigate the effectiveness of adding three organic manures (farmyard manure @10 t/ha, vermicompost @ 2.5t/ha, and biogas slurry @ 2.5t/ha) in combinations with graded dose of chemical fertilizers (75%, 100%, and 125% recommended dose of fertilizers) and microbial inoculations, i.e., salinity tolerant strain of Azotobacter chroococcum (Mac 27) and Biomix [Azotobacter (Mac 27) + Azospirillum (J 11-12) + phosphate solubilizing bacterias (p 36)] on the productivity of wheat crop irrigated with saline water (7.5–8.0 dS/m). The recommended dose of fertilizer + farmyard manure + Biomix resulted in significant improvement in growth parameters and grain yield (49.78 q/ha), straw yield (71.72 q/ha), biological yield (121.5 q/ha) of the wheat crop as compared to the control and recommended dose of fertilizer. The highest gross returns (Rs. 112,476), net returns (Rs. 38,615), and B:C (1.52) were also realized in the same treatment. The integrated nutrient application had improved the viable microbial count of Azotobacter, Azospirillum, and phosphate solubilizing bacteria as compared to control (untreated) and inorganic fertilizer treatments. Soil electrical conductivity and pH were decreased, while organic carbon increased by farmyard manure, vermicompost, and biogas slurry application when compared with the control (untreated). The availability of nitrogen, phosphorus, and potassium in soil also significantly improved over the control and sole recommended dose of fertilizer treatments. Hence, in North-Western plains of India having the problem of salinity, wheat can be profitably cultivated by the adoption of integrated nutrient management practices. [ABSTRACT FROM AUTHOR]

Summary: The quantitative and spatial coordination of stomatal pores in the epidermis and airspaces in the underlying mesophyll tissue is vital for efficient gas exchange in the leaf. The mechanisms that determine the distribution of stomata in the epidermis have been studied extensively, but how this relates to the regulation of mesophyll airspace configuration is poorly understood. Recent studies have investigated how development is coordinated between these tissue layers. The evidence suggests that multiple mechanisms are likely to work concurrently to coordinate stomatal and mesophyll development for optimal leaf gas exchange, and that both genetic and physiological factors contribute to this regulation. Such advances in our understanding of leaf development have important implications for potential improvement of crop water use efficiency. [ABSTRACT FROM AUTHOR]

The study was conducted to determine the feasibility of canopy temperature based crop water stress index (CWSI) for scheduling irrigation of Indian mustard (Brassica juncea). Field crop experiments were conducted in Hamirpur, Himachal Pradesh (India) during three consecutive cropping seasons (2015, 2016 and 2017). The experimental field was divided into five plots with different levels of irrigation treatments based on depletion of total available soil water (TASW) in the crop root zone. The maximum soil moisture depletion (SMD) of TASW at 10%, 30% and 50%, full irrigated (non‐stressed) and extremely dry (full stressed) conditions were maintained in respective plots. Relationships were developed between canopy‐air temperature differential (TC‐TA) and vapour pressure deficit (VPD) for non‐stressed and fully stressed conditions to generate non‐water‐stressed baseline (NWSB) and maximum water‐stressed baseline (MWSB) baselines for Indian mustard crop. The CWSI was computed for different SMD of TASW by using a proven empirical approach based on the baselines. The irrigation treatment corresponding to 30% SMD with a mean CWSI of 0.4 resulted in optimal yield and maximum water use efficiency. Results of the study suggest that established CWSI value can be used to detect stress and schedule irrigations for Indian mustard. [ABSTRACT FROM AUTHOR]

Copyright of Irrigation & Drainage is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study we gained insights into the effects of the supplementation with Lactobacillus acidophilus D2/CSL (CECT 4529) in the chicken drinking water on crop and caeca microbiomes. The probiotic was supplemented at the concentrations of 0.2 g Lactobacillus acidophilus/day/bird and 0.02 g Lactobacillus acidophilus/day/bird and its effect on the crop and caeca microbiomes was assessed at 14 and 35 days of rearing. The results showed that mean relative abundance of Lactobacillus acidophilus in the caeca did not show significative differences in the treated and control birds, although Lactobacillus acidophilus as well as Faecalibacterium prausnitzii, Lactobacillus crispatus and Lactobacillus reuteri significantly increased over time. Moreover, the treatment with the high dose of probiotic significantly increased the abundance of Clostridium asparagiforme, Clostridium hathewayi and Clostridium saccharolyticum producing butyrate and other organic acids supporting the chicken health. Finally, at 35 days, the Cell division protein FtsH (EC 3.4.24.-) and the Site-specific recombinase genes were significantly increased in the caeca of birds treated with the high dose of probiotic in comparison to the control group. The results of this study showed that Lactobacillus acidophilus D2/CSL (CECT 4529) supplementation in the drinking water at the concentrations of 0.2 and 0.02 g Lactobacillus acidophilus/day/bird improved beneficial microbes and functional genes in broiler crops and caeca. Nevertheless, the main site of action of the probiotic is the crop, at least in the early stage of the chicken life. Indeed, at 14 days Lactobacillus acidophilus was significantly higher in the crops of chickens treated with the high dose of LA in comparison to the control (14.094 vs 1.741%, p = 0.036). [ABSTRACT FROM AUTHOR]

In arid and semi-arid irrigated croplands, the excessive accumulation of soluble salts in the root zone is an extensive problem that seriously limits crop yield and water productivity (WP). To avoid affects the yield potential of crops, the application of extra irrigation for leaching of excessive salts from the root zone was required. Quantitative knowledge of effects of the irrigation water salinity and leaching fraction (LF) on the relative yield (RY) and the unit water productivity of crop evapotranspiration (UWPET) and the unit water productivity of irrigation water (UWPI) were becoming gradually important. This article provided theoretical models for estimating the UWPs (UWPET and UWPI) and optimizing leaching fraction according to irrigation water salinity. In the present study, eight levels of irrigation water salinity (ECw = 0.25, 0.50, 0.75, 1, 2, 3, 4, and 5 dS/m) and 39 levels of LF values ranging from 0.04 to 0.80 were set and tested to assessing their effects on the RY and UWPs for four typical crops (barley, bean, wheat, and maize) with different salt tolerance levels. Almost every curve determined between the UWPs and LFs for the four crops had an inflection point. It was indicated that the UWPET and UWPI could be maximized by optimizing the LF under different irrigation water salinities. Furthermore, the linear regression relationships were established to estimate the maximum values of UWPs and their corresponding optimal LFs for four crops by using the irrigation water salinity. Moreover, the theoretical models for estimating the UWPs were validated by data of wheat from previous literature, and the models could be suitable with acceptable relative errors when LFs ranging from 0.07 to 0.17. [ABSTRACT FROM AUTHOR]

Spatial trends of rainfall and reference evapotranspiration (ETo) are crucial for sustainable water resources management. Rainfall and ETo trends were evaluated and estimated using FAO Penman Monteith model and their spatial distributions were mapped across the Southeast Nigeria. Two spatial interpolation techniques, Inverse Distance Weighting (IDW) and Kriging in ArcGIS were employed for monthly, annual and seasonal rainfall and ETo. Results showed that rainfall increased gradually from North to South while ETo increased from South to North of the study area. ETo was found to be higher during dry seasons as the average rise in temperature within the period of study stood at 1.1%. There was a positive correlation of the predicted results obtained by the IDW and kriging methods with measured rainfall and ETo data, evaluated at R = 0.87(rainfall) and R = 0.83 (ETo) for IDW method, and R = 0.92 (rainfall) and R = 0.50 (ETo) for kriging method. This study provides background information on rainfall, ETo and climatic conditions for climate change studies, efficient crop water and environmental management. [ABSTRACT FROM AUTHOR]

Almost all countries in the world have used lettuce hydroponic cultivation in planthouses because it is appropriate for plant growth and production. The microclimate inside planthouse is an environmental factor that affects plant growth and development. Vegetables planted in the planthouse have a great deal of water requirement. Selecting a method with a more accurate estimation of crop evapotranspiration is a critical factor for efficient water management. In this research, the climates that are affecting the lettuce evapotranspiration with modification of floating hydroponic technique inside the planthouse were investigated. The objectives of this research are to figure out the microclimate, the appropriate model of the potential evapotranspiration, and the temporal crop coefficients and water productivity of lettuce grown using a floating hydroponic technique in a planthouse. Experimental planthouse uses 90% transparency of polycarbonate roofs and net walls, with the dimension is 9 × 3 × 4 m. Primary data collected in the form of water level, and climate data for both inside and outside the planthouse. Potential evapotranspiration (ETp) value was estimated using seven models of potential evapotranspiration and among those models, the most appropriate model is determined. The climate inside the planthouse was significantly different than that in the outside. In which during 40 days of lettuce cultivation, solar radiation and relative humidity in the inside were lower than in the outside, but the temperature inside was higher than the outside. Potential evapotranspiration inside the planthouse can be estimated precisely by Hargreaves model. Crop coefficient (Kc) changed with time forming a parabolic equation started at 0.7 then decreased to reach 0.4 then increase to 1.4. Lettuce productivity was 1114.6 g m-2 having water productivity 29.58 g L-1 which was linearly related to the consumptive use of water by the plant. [ABSTRACT FROM AUTHOR]

Agricultural water demands can conflict with habitat needs in many North Coast watersheds. Understanding different water use patterns can help reduce conflict over limited supplies. We measured on-farm crop water use and conducted grower interviews to estimate the agricultural water demand in the upper Russian River and Navarro River watersheds. Annual agricultural water demand was less than 11% in the Russian River, and 2% in Navarro River, of the total annual discharge in each watershed. However, because demands are concentrated in the dry season when instream flows are at a minimum, these relatively small amounts can represent a significant constraint to stream habitat conditions. We have shared our study results in broad basin and community water resource planning efforts, including flow management of the Russian and Navarro rivers and implementation of the Sustainable Groundwater Management Act in the Ukiah Basin. Findings and recommendations from this study have influenced on-the-ground solutions to meet water demand in these watersheds, including construction of off-stream wintertime storage capacity to replace summertime stream diversions, and use of a municipal recycled water conveyance system as a replacement for summer diversions. [ABSTRACT FROM AUTHOR]

Copyright of Journal of College of Education / Wasit is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Caatinga is the property of Revista Caatinga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Regional, automated meteorological networks, such as the Oklahoma Mesonet can potentially provide high quality forcing data for generating gridded surfaces, but proven methods of interpolating weather variables between the station locations are needed. We compared two interpolation methods, ordinary kriging (OK) and empirical Bayesian kriging (EBK), with and without using long-term climate imprints (CI), for creating spatially continuous, daily weather datasets. Daily meteorological variables (maximum and minimum temperature, solar radiation, and precipitation) from the Oklahoma Mesonet for the period 1997- 2014were interpolated using geoprocessing tools inArcGIS. Cross-validationwas used for evaluation of interpolationmethods, with 90% of sites chosen randomly for the training set and the remaining 10% left for validation. For all interpolation approaches, cross-validation showed coefficient of determination (R²) values of .99 and .98 for daily maximum and minimum air temperatures, with mean absolute error (MAE) ranging from ±0.45-0.50 °C for maximum temperature and ±0.77-0.80 °C for minimum temperature. Likewise, for daily solar radiation, R² values of .94 and .93 showed overall good prediction accuracy with MAE values 1.00 and 1.01 MJ m-2 d-1 for EBK and OK, respectively. However, for rainfall, all methods yielded R² values ≤.67, suggesting a need for more effective interpolation method. Based on its lower computational time and lower input data requirement, OK appears preferable to the other approaches tested here to provide the daily weather data for gridded models in Oklahoma and other regions with similar monitoring networks. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The rapid increase in world population has increased the demand of food and biofuels leading to stress on water resources and increase in competition between different sectors around the globe. Under the combined impacts of climate change, population growth, urbanization and economic development, the pressure on the water resources is continually increasing. Therefore, an appropriate approach is required for effective water accounting. Water footprint concept has been introduced to indicate the water use and impact of production systems on water resources. In this study, two different approaches for the estimation of water footprint of crops have been reviewed, i.e. the Water Footprint Network (WFN) approach and Life Cycle Assessment (LCA). These approaches are used in many countries and numerical models have been developed to facilitate the calculations. By clarifying the concerns about water accounting, we identify that the main differing perspective between the WFN and LCA approaches is that LCA aims to account for the environmental impacts related to water resources, while WFN aims to account for water productivity of global fresh water as a limited resource. We conclude that the WFN approach could benefit from considering the impact assessment methodologies evolving within the LCA community and joint efforts could lead to some consensual metrics to better assess the sustainability of freshwater use. [ABSTRACT FROM AUTHOR]

Relationship between canopy temperature and soil moisture is important for using the potential of canopy temperature as an indicator of crop water stress. A two-year field experiment was carried out during June to September 2016 and 2017 at the Research Station of College of Agriculture, Darab, Shiraz University, Iran, to determine crop water stress index (CWSI) for bur clover. Irrigation regimes including well-watered [Irrigation according to 100% field capacity (FC)], mild water stress (75% FC), severe water stress (50% FC), and most severe water stress (25% FC) were arranged in a randomized complete block design with four replications. In 2016, CWSI values showed an increasing trend from June (0.066 in well-watered) to August (0.821 in most severe water stress) as a result of higher vapor pressure deficit (VPD) and depression in canopy-air temperature differences (Tc-Ta). A similar trend was observed in the second year. In both years, by increase in mean temperature from June to August, Tc-Ta differential increased and the highest monthly average value of CWSI for all treatments was obtained in August. By enhancing water stress, the color grading score decreased sharply (from 6 to 3) and stayed constant (2) for August and September. Also, a negative relationship was observed between CWSI and dry matter production (R2 = 0.88**) and color quality (R2 = 0.94**). It was concluded that mild water stress (75% FC) with mean seasonal CWSI being ranged about 0.198 to 0.294, without any loss in visual color quality might be the best irrigation regime for bur clover production. [ABSTRACT FROM AUTHOR]

Copyright of Mediterranean Agricultural Sciences is the property of Akdeniz Universitesi Ziraat Fakultesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mediterranean Agricultural Sciences is the property of Akdeniz Universitesi Ziraat Fakultesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This work deals with the regulation of water pollution caused by the use of nitrogen in agriculture. We investigate the policy instruments that should be implemented to induce socially optimal water quality. To do so, we propose a dynamic theoretical framework. We focus on the potential of cover crops to preserve water quality by considering the impact of soil quality on water quality to be endogenous: we consider two interrelated dynamic equations, one for soil quality and one for water pollution, that interact through soil quality. The land area devoted to cover crops increases the soil quality stock which, in turn, decreases the water pollution stock. We show that the socially optimal fiscal scheme consists in two parts: one that acts at the intensive margin (proportional to nitrogen use) and one at the extensive margin (proportional to land cultivated with cover crops). [ABSTRACT FROM AUTHOR]

This paper discusses the effects of long-term environmental change (represented by the abundance or scarcity relative to the long-term average level of crop yield/river flow) and short-term environmental shock (represented by the maximum number of consecutive years below the median crop yield/river flow per decade) on population redistribution in Mexico and Ethiopia. Crop production and water resources, which are affected by climate change and influence human survival and activities, were selected as research variables. Two developing countries, namely, Mexico and Ethiopia, were selected as comparison cases. The results showed that short-term environmental shocks had no correlation with population redistribution. Short-term environmental shocks might fail to influence migration decisions or cause only temporary displacements that cannot be detected by demographic statistics. Among the long-term environmental change factors, only crop yield deviation was found to have a significant positive correlation with population redistribution. Based on two different datasets and two different decades, crop yield deviation is positively correlated with population redistribution; the correlation coefficients between crop yield deviation and population redistribution were 0.134 to 0.162 in Mexico and 0.102 to 0.235 in Ethiopia. When urbanization was considered as the control variable, the correlation coefficient between crop yield deviation and population redistribution in Mexico dropped by half, while it was almost the same in Ethiopia. However, Ethiopia's population redistribution was more clearly influenced by the population itself. Crop yield deviation relative to water flow deviation meant changes in livelihoods. Population redistribution is a possible means of adapting to changes in livelihood. Mexico exhibited high resilience to changes in livelihoods caused by long-term environmental change, especially in its densely populated areas. In contrast, Ethiopia was characterized mainly by high population growth and low population migration. People in some areas of Ethiopia were forced to endure hardship of livelihood deterioration or to stay where they were due to the difficulty of obtaining sufficient resources to afford the cost of migration. [ABSTRACT FROM AUTHOR]

Copyright of Anuario do Instituto de Geociencias is the property of Universidade Federal do Rio de Janeiro, Instituto de Geociencias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effect of sodium silicate on the morphological parameters of tomato (Lycopersicon esculentum Mill. var. Pusa Sheetal) was analyzed at vegetative, flowering and fruiting stages. The significant increase in morphological parameters of tomato plants was observed with sodium silicate treatment in comparison to control. The increase in the height of tomato plants 34.27 and 14.61% was observed with 5 g and 7 g sodium silicate treatment respectively in comparison to control. The findings of the present study revealed that sodium silicate stimulated tomato plant growth under water deficit conditions and it can be used in drought prone areas for the protection of tomato crop against water stress. [ABSTRACT FROM AUTHOR]

In the present study, two districts of North-East region of Bangladesh; a flood prone area with high temperature and maximum precipitation, respectively, were selected along-with two widely cultivated Boro rice varieties in Bangladesh. Reference evapotranspiration (ETO) during the study period from 1994 to 2010 was estimated with the daily meteorological data utilizing the FAO Penman-Monteith method. A MAKESENS trend model was adopted for the assessment of both Mann-Kendall test and Sen's rate of change over the study period. During the study period, the potential crop water requirement of Bangladesh Rice Research Institute dhan 28 (B28) and BRRI dhan 29 (B29) in Moulvibazar has been declined by -3.953 mm year-1 and -5.182 mm year-1, respectively; whereas it has been raised by 2.483 mm year-1 and 2.387 mm year-1, respectively in Sylhet. The climatic parameters affecting the observed and projected trends in Potential water requirement differed both significantly and insignificantly over the months of the year. For both varieties, maximum water demand was observed in mid-season stage; whereas the development stage, the water demand was found to be minimum. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Agricultura Irrigada - RBAI is the property of Revista Brasileira de Agricultura Irrigada - RBAI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Agriculture faces the great challenge of developing strategies to maintain production while simultaneously reducing environmental impacts. The trade-off between crop production and water quality services is one of the most serious issues facing agriculture, and interest in achieving win-win outcomes through management of ecosystem services is growing. Although wetlands can reduce nitrogen loads, it is unclear whether maintaining and restoring wetlands can ameliorate the trade-off between crop production and water quality and thereby increase the likelihood of win-win outcomes. We defined the orthogonal residuals from the regression line relating the trade-offs between two conflicting services as the degree to which the trade-off was mitigated (mitigation effectiveness score). The more positive the residual, the higher mitigation effectiveness score, and the greater the potential to mitigate the trade-off. We measured nitrate concentrations, as an indicator of water quality, five times during summer and winter across 49 sub-watersheds of the watershed of Lake Kasumigaura, which is highly nitrogen-loaded by agriculture. We quantified the mitigation effectiveness score from the trade-off relationships between cropland area and nitrate concentrations, and we also identified landscape and environmental factors that affected these scores. Some sub-watersheds in our study had high cropland cover but low nitrate concentrations. Overall, we found that mitigation effectiveness scores were positively associated with wetland cover at all sampling times. Other factors, including covers of paddy rice fields, abandoned rice fields, and impervious surfaces, and dissolved organic carbon concentrations, had no significant effects on mitigation effectiveness scores, although these factors were considered to increase nitrogen removal. Our findings suggest that maintaining and restoring wetlands might mitigate the trade-off between crop production and water quality and thereby enhance the likelihood of win-win outcomes in agricultural landscapes. Because wetland area has decreased, flooding or ponding abandoned rice fields may be an important alternative management option. The nitrate concentrations we observed met the water quality standard for drinking water, but the fact that they sometimes exceeded the nitrogen environmental target adopted within Lake Kasumigaura in terms of eutrophication suggests that simultaneous reduction of croplands and fertilizer inputs should still be encouraged. [ABSTRACT FROM AUTHOR]

After the disaster, the increase of suspended matter in water and the high water content crops will lead to the low accuracy of conventional methods of water body information extraction. In response to this problem, a new method of extracting flood submerging area for farmland based on tasseled cap transformation is presented in this paper. First, the remote sensing images before and after disaster are pre-processed by radiometric calibration and atmospheric correction. Then, the tasseled cap transformation is performed based on the coefficients corresponding to the sensor to obtain the greenness component and the wetness component. Third, the wetness component is divided by the OTSU method, and combined with the greenness component to obtain the warterbody information. Finally, the spatial overlay analysis of the waterbody information and farmland vector data is carried out to extract the flood submerging area for farmland. Taking Yueyang City of Hunan Province and its vicinity as research area, the accuracy of the proposed method is evaluated both qualitatively and quantitatively to verify the validity and applicability of the method. The results shows that the boundary of flood submerging area for farmland is clear, the range is more accurate, and the producer's accuracy and the user's accuracy are 0.97 and 0.90, respectively. This paper provides references for agricultural risk evaluation and dynamic monitoring of flood disaster. [ABSTRACT FROM AUTHOR]

Integrating crop species with different photosynthetic pathways has great potential to increase efficiency in the use of scarce resources. In order to tap the resource complementarity emanating from this mix, this study intercropped potato (Solanum tuberosum L.) with lima bean (Phaseolus lunatas L.) and dolichos (Lablab purpureous L.), and related soil temperature with radiation use efficiency and crop water productivity of rainfed potato in the upper midland (1552 m above sea level (masl), lower-highland (1854 masl) and upper-highland (2553 masl)) agro-ecological zones of Kenya. Leaf area index (LAI), light interception, soil temperature and soil water contents (SWC) were quantified at different stages of potato growth and related with the radiation use efficiency (RUE) and crop water productivity (CWP) of potato. Intercropping increased crop LAI by 26–57% relative to sole potato stands and significantly lowered the soil temperatures in the 0–30 cm depth by up to 7.3 °C. This caused an increase in SWC by up to 38%, thus increasing RUE by 56–78% and CWP by 45–67%. Intercropping potato with legumes is coupled with optimum root-zone soil temperature and soil water content, thus potentially exerting additive relations in radiation interception and subsequent conversion into crop biomass. [ABSTRACT FROM AUTHOR]

We use published water balance data from irrigated cropping to show that water entitlements acquired for environmental purposes through water infrastructure subsidies in the Murray–Darling Basin, Australia, have resulted in smaller increases in net stream and river flows than is estimated by the Australian Government, and may even have reduced net stream and river flows. Two key policy implications arising from our results are: (1) subsidies to improve irrigation efficiency so as to increase stream and river flows must employ water accounting so that the effects on return flows are known and the volume of water extracted for irrigation is adjusted to achieve desired stream and river flows; and (2) if the net increases in stream and river flows in the MDB are much less than estimated by the Australian Government, water infrastructure subsidies to increase irrigation efficiency may have compromised the delivery of key objects of the Water Act (2007). [ABSTRACT FROM AUTHOR]

The water allowance for canal systems of Pakistan was designed considering the average values of cropping intensity and irrigation area. However, water allowances would be different if estimated on the basis of real cropping intensities, cropping pattern and actual evapotranspiration. This inequity of water allocation results in decreased agricultural production. Hence, optimal water allowances for given canal commands need to be developed to maximize the efficiency of the existing irrigation system. Therefore, present study aims to assess the difference between the available water supplies and those required on the basis of real field conditions. Crop Water Allocation Model has been used for this purpose. Discharge at the head of each watercourse was predicted on the basis of the actual evapotranspiration, cropping patterns, cropping intensity, the number of days of canal flows in a year and the irrigation efficiency. The predicted optimal water requirements and the design flow rate were also compared for Kasur minor and found that 59 watercourses out of 61 require less water for optimal operation than the designed flow rate. Only two watercourses require more water for optimal conditions than the designed flow rate. Sensitivity and scenario analysis were also performed to evaluate the impact of different agricultural and climatological parameters on the reference crop evapotranspiration and design discharges. [ABSTRACT FROM AUTHOR]