Could saline irrigation clear all residual common bile duct stones after lithotripsy?A self-controlled prospective cohort study

BACKGROUND A previous study showed that irrigation with 100 mL saline reduced residual common bile duct(CBD)stones,which potentially cause recurrent stones after endoscopic retrograde cholangiopancreatography.AIM To determine whether saline irrigation can improve CBD clearance after lithotripsy.METHODS This prospective self-controlled study enrolled patients receiving mechanical lithotripsy for large(>1.2 cm)CBD stones.After occlusion cholangiography confirmed CBD stone clearance,peroral cholangioscopy(POC)was performed to determine clearance scores based on the number of residual stones.The amounts of residual stones spotted via POC were graded on a 5-point scale(score 1,worst;score 5,best).Scores were documented after only stone removal(control)and after irrigation with 50 mL and 100 mL saline,respectively.The stone composition was analyzed using infrared spectroscopy.RESULTS Between October 2018 and January 2020,47 patients had CBD clearance scores of 2.4±1.1 without saline irrigation,3.5±0.7 with 50 mL irrigation,and 4.6±0.6 with 100 mL irrigation(P<0.001).Multivariate analysis showed that CBD diameter>15 mm[odds ratio(OR)=0.08,95%confidence interval(CI):0.01-0.49;P=0.007]and periampullary diverticula(PAD)(OR=6.51,95%CI:1.08-39.21;P=0.041)were independent risk factors for residual stones.Bilirubin pigment stones constituted the main residual stones found in patients with PAD(P=0.004).CONCLUSION Irrigation with 100 mL of saline may not clear all residual CBD stones after lithotripsy,especially in patients with PAD and/or a dilated(>15 mm)CBD.Pigment residual stones are soft and commonly found in patients with PAD.Additional saline irrigation may be required to remove retained stones.

Effects of saline irrigation on soil salt accumulation and grain yield in the winter wheat-summer maize double cropping system in the low plain of North China

In the dominant winter wheat （WW）-summer maize （SM） double cropping system in the low plain located in the North China, limited access to fresh water, especially during dry season, constitutes a major obstacle to realize high crop productivity. Using the vast water resources of the saline upper aquifer for irrigation during WW jointing stage, may help to bridge the peak of dry season and relieve the tight water situation in the region. A field experiment was conducted during 2009-2012 to investigate the effects of saline irrigation during WW jointing stage on soil salt accumulation and productivity of WW and SM. The experiment treatments comprised no irrigation （T1）, fresh water irrigation （T2）, slightly saline water irrigation （T3：2.8 dS m-l）, and strongly saline water irrigation （T4：8.2 dS m-1） at WW jointing stage. With regard to WW yields and aggregated annual WW-SM yields, clear benefits of saline water irrigation （T3 ＆ T4） compared to no irrigation （T1）, as well as insignificant yield losses compared to fresh water irrigation （T2） occurred in all three experiment years. However, the increased soil salinity in eady SM season in consequence of saline irrigation exerted a negative effect on SM photosynthesis and final yield in two of three experiment years. To avoid the negative aftereffects of saline irrigation, sufficient fresh water irrigation during SM sowing phase （i.e., increase from 60 to 90 mm） is recommended to guarantee good growth conditions during the sensitive early growing period of SM. The risk of long-term accumulation of salts as a result of saline irrigation during the peak of dry season is considered low, due to deep leaching of salts during regularly occurring wet years, as demonstrated in the 2012 experiment year. Thus, applying saline water irrigation at jointing stage of WW and fresh water at sowing of SM is most promising to realize high yield and fresh irrigation water saving.

Effects of organic amendments on soil properties and growth characteristics of Melon(Cucumis melo L.)under saline irrigation

Establishing strategies of organic amendments application to mitigate the adverse effects of saline irrigation are essential for the sustainable agriculture.A two-year pot experiment was conducted using combinations of organic amendments including effective microorganisms(EM),biochar(BC)and digestate(Di)to investigate their effects on soil and melon(Cucumis melo L.)compared with the recommended NPK fertilizer and Control(CK)under two levels of irrigation water salinity(SL0:0.25 dS/m,SL1:2.0 dS/m).Results showed combined applications of organic amendments could significantly(p<0.05)increase soil pH and organic matter(OM)compared to NPK and CK.Application of organic amendments containing BC evidently increased the sodium adsorptive capacity(SAC)under saline water solution.The combined application of EM,BC and Di(EM+BC+Di)could significantly(p<0.05)improve soil available water retention under SL0 and SL1 compared with other treatments.Results also showed organic amendments application can significantly(p<0.05)enhance the photosynthetic rate(Pr)and reduce sodium ion(Na+)content in melon leaves.EM+BC+Di could significantly(p<0.05)increase water use efficiency(WUE)and fruit yield of melon under SL0 and SL1 in comparison to other treatments.It proved that EM+BC+Di had a positive effect on soil improvement,melon growth,WUE and fruit yield.Moreover,EM+BC+Di could be used as an alternative strategy for mineral NPK fertilization of melon at reasonable dosages and frequencies under saline irrigation.

Saline Water Irrigation Scheduling Through a Crop-Water-Salinity Production Function and a Soil-Water-Salinity Dynamic Model

Using a crop-water-salinity production function and a soil-water-salinity dynamic model, optimal irrigation scheduling was developed to maximize net return per irrigated area. Plot and field experiments were used to obtain the crop water sensitivity index, the salinity sensitivity index, and other parameters. Using data collected during 35 years to calculate the 10-day mean precipitation and evaporation, the variation in soil salinity concentrations and in the yields of winter wheat and cotton were simulated for 49 irrigation scheduling that were combined from 7 irrigation schemes over 3 irrigation dates and 7 salinity concentrations of saline irrigation water (fresh water and 6 levels of saline water). Comparison of predicted results with irrigation data obtained from a large area of the field showed that the model was valid and reliable. Based on the analysis of the investment cost of the irrigation that employed deep tube wells or shallow tube wells, a saline water irrigation schedule and a corresponding strategy for groundwater development and utilization were proposed. For wheat or cotton, if the salinity concentration was higher than 7.0 g L-1 in groundwater, irrigation was needed with only fresh water; if about 5.0 g L-1, irrigation was required twice with fresh water and once with saline water; and if not higher than 3.0 g L-1, irrigation could be solely with saline water.

Effects of deficit irrigation with saline water on spring wheat growth and yield in arid Northwest China

Field experiments were conducted in 2008 and 2009 to study the effects of deficit irrigation with saline water on spring wheat growth and yield in an arid region of Northwest China. Nine treatments included three salinity levels sl, s2 and s3 （0.65, 3.2, and 6.1 dS/m） in combination with three water levels wl, w2 and w3 （375, 300, and 225 mm）. In 2008, for most treatments, deficit irrigation showed adverse effects on wheat growth; meanwhile, the effect of saline irrigation was not apparent. In 2009, growth parameters of wl treatments were not always optimal under saline irrigation. At 3.2 and 6.1 dS/m in 2008, the highest yield was obtained by wl treatments, however, in 2009, the weight of 1,000 grains and wheat yield both followed the order w2 〉 wl 〉 w3. In this study, spring wheat was sensitive to water deficit, especially at the booting to grain-filling stages, but was not significantly affected by saline irrigation and the combination of the two factors. The results demonstrated that 300-mm irrigation water with a salinity of less than 3.2 dS/m is suitable for wheat fields in the study area.

Effect of different water application intensity and irrigation amount treatments of microirrigation on soil-leaching coastal saline soils of North China

In coastal regions, Bohai Gulf is one of the most affected areas by salinization. To study the effects of mocrosprinkler irrigation on the characteristics of highly saline sandy loam soil（ECe（saturated paste extract）=22.3 d S m^–1; SAR（sodium adsorption ratio）=49.0） of North China, a laboratory experiment was conducted. Five water application intensity（WAI） treatments（1.7, 3.1, 5.3, 8.8, and 10.1 mm h^–1）, five irrigation amount（IA） treatments（148, 168, 184, 201, and 223 mm） and three time periods of water redistribution（0, 24 and 48 h） were employed in the study. A compounding microsprinkler system was used for the WAI treatments, and a single microsprinkler was used for the IA treatments. The results indicated that, as soil depth increased, soil water content（θ） increased and then slightly decreased; with WAI and IA consistently increasing, the relatively moist region expanded and the average θ increased. Meanwhile, soil ECe increased as soil depth increased, and the zone with low soil salinity expanded as WAI and IA increased. Although the reduction of the average SAR was smaller than that of the average electrical conductivity of the ECe, these variables decreased in similar fashion as WAI and IA increased under microsprinkler irrigation. The average p H decreased as soil depth increased. Longer time periods of water redistribution led to lower salinity and slight expansion of the SAR zone. Considering the effects of leached salts in coastal saline soils, greater WAI and IA values are more advantageous under unsaturated flow conditions, as they cause better water movement in the soil. After leaching due to microsprinkler irrigation, highly saline soil gradually changes to moderately saline soil. The results provide theoretical and technological guidance for the salt leaching and landscaping of highly saline coastal environments.

Maximizing Irrigation Water Productivity by Optimizing Leaching Fraction

The importance of maximizing irrigation water productivity is increasing as the water resources still decreasing and deteriorating due to environmental interactions. An optimal irrigation water depth （including leaching water depth） was estimated in order to maximize water unit volume productivity by using the optimal leaching fraction （LF）, which is calculated by the new proposed model--unit yield ratio （UYR%） and irrigation depth ratio （IDP）. A computer program was constructed to apply this model for several crops irrigated by two water resources--river and well. The water salinity of river was 1.1 dS/m and the well salinity was 3.85 dS/m. The results showed that there is an optimal leaching requirement （LR） value for each crop irrigated by any water resource. The maximum UYR% of the alfalfa irrigated by saline well water was 58.45% with the optimal LF = 0.4, while the maximum UYR% of the bean irrigated by river water was 78.58% with the optimal LR = 0.2. The optimal LF is saving water by increasing the productivity of irrigation water unit volume, especially when using saline irrigation water, for example, an increase of IDP for alfalfa by only 20%, followed by an increase of UYR% about 47.5% （from 12% to 57%） by increasing LF from 0.1 to 0.3.

Effect of Saline Aquaculture Effluent on Salt-Tolerant Jerusalem Artichoke (Helianthus tuberosus L.) in a Semi-Arid Coastal Area of China

An experiment with six treatments: CK1 (rainfed), CK2 (irrigated with freshwater), and 4 treatments of saline aquaculture effluent blended with brackish groundwater at different ratios of 1:1, 1:2, 1:3, and 1:4 (v/v) was carried out during 2004 to assess the effect of saline aquaculture effluent on plant growth and soil properties in the Laizhou region, Shandong Province, China and to determine an optimal salinity threshold for aquaculture effluent. Cumulative evapotranspiration for the saline aquaculture effluent irrigation and non-irrigation treatments was lower than that for the freshwater irrigation treatment. Soil electrical conductivity was higher with respect to saline aquaculture effluent irrigation treatment compared to that with respect to non-irrigation or freshwater irrigation treatment. For Jerusalem artichoke (Helianthus tuberosus L.), in comparison to the freshwater treatment, plant height and aboveground biomass for the 1:3 and 1:4 treatments were constrained, whereas stem width and root biomass were enhanced. Concomitantly, higher tuber yield was obtained for the 1:3 and 1:4 treatments compared to that for CK1 and 1:1 treatments. Nitrogen and phosphorus were higher in tubers of the 1:4 treatment. This study demonstrated that saline aquaculture effluent could be used successfully to irrigate Jerusalem artichoke with higher tuber yield and nutrient removal.

An Empirical Framework of Washing Salinity by Irrigation to Maintain Soil Quality in Hetao Irrigation District

[Objectives] To summarize the characteristics of washing salinity by irrigation in Hetao Irrigation District, and propose the empirical framework of washing salinity by irrigation to maintain soil quality, and provide a theoretical basis for maintaining the sustainable development of soil in Hetao Irrigation District. [Methods] The methods of experiment, questionnaire, on-the-spot investigation and literature review were used. [Results] This study proposed the empirical framework of washing salinity by irrigation to maintain soil quality in Hetao Irrigation District. Seven factors of the framework, including flood irrigation, land leveling, plastic film mulching, fertilization, soil organic matter, pH and salinity, and their relationships were determined. The characteristics of these factors in Hetao Irrigation District were investigated(flooding irrigation with a large amount of irrigation water, high amount of fertilizer application, low organic matter, high pH, large variation of salinity, etc.). The mechanisms and effects of various factors affecting soil quality in Hetao Irrigation District were analyzed(the mean soil organic matter(SOM) and pH were kept in the range of 10.9-13.9 g/kg and 8.0-8.15 in recent 35 years, respectively, and increased slightly, etc.). [Conclusions] The empirical framework can be used as a theoretical norm for evaluating soil quality under the condition of washing salinity by irrigation. Under the condition of washing salinity by irrigation, the agricultural soil quality in Hetao Irrigation District showed a stable trend over time. Using this framework, we can find soil problems, and adjust some unbalanced factors to maintain the stability of soil quality in Hetao Irrigation District, and can also provide a reference for other areas.

Biochemical Mechanism Unlocking Their Potential Role in Salt Tolerance Mechanism of Zizyphus Germplasm

Salinity is one of the major constraints reducing plant growth and yield.Irrigation with poor quality and brackish water to orchards is a major cause of stunted growth and low yield.The salt tolerance mechanism is one of the complicated genomic characters that is very problematic to develop in fruit trees and becomes much more severe at any growth and developmental stage.Osmotic stress and hormonal imbalances are major constraints causing low biomass production.Fruit tree tolerance/sensitivity is chiefly based on the activation of a defense system comprised of super-oxidase dismutase(SOD),peroxidase(POD)and catalases(CAT),non-enzymatic compounds including ascorbic acid,phenolics,flavonoids,stress indicators[i.e.,hydrogen peroxide(H2O2),lipid peroxidation,malondialdehyde(MDA),reactive oxygen species(ROS)and osmolytes containing proline,glycine-betaine(GB),ascorbates(APX),glutathione peroxidase(GPX)and glutathione reductase(GR)].Tolerant genotypes must have higher antioxidant assays to cope with the adverse effects of salinity stress because their defense system had the potential to scavenge toxic ROS and protect from membrane leakage.Some work is conducted on agronomic and horticultural crops;however,underutilized fruit crops are still neglected and need serious consideration from plant researchers.Minor fruit crops especially Zizyphus had excellent nutritional aspects.The current study provides detailed insights into the physiological and biochemical mechanisms of Zizyphus species to cope with the adverse effects of salinity by improving their plant defense system.The development of salt-tolerant germplasm is a requisite and can be developed by utilization of physiological,biochemical,and molecular mechanisms.Application of different molecular approaches(i.e.,genome mapping,genome editing,genetic transformation,proteomics,transcriptomics,and metabolites)are effective for higher yield by improving tolerance mechanisms.

Effects of irrigation water salinity on soil salt content distribution,soil physical properties and water use efficiency of maize for seed production in arid Northwest China

In order to explore the use of groundwater resources,field experiments were conducted for three consecutive years during 2012-2014 in the Shiyang River basin of Northwest China.Irrigation was conducted using four different water salinity levels that were arranged in a split plot design.These four water salinity levels were s0,s3,s6 and s9(0.71,3,6 and 9 g/L,respectively).The soil salt content,soil bulk density,soil porosity,saturated hydraulic conductivity,plant height,leaf area index and yield of maize for seed production were measured for studying the effects of saline water irrigation on soil salt content distribution,soil physical properties and water use efficiency.It was observed that higher salinity level of irrigation water and long duration of saline water irrigation resulted in more salt accumulation.Compared to initial values,the soil salt accumulation in 0-100 cm soil layer after three years of experiments for s0,s3,s6 and s9 was 0.189 mg/cm3,0.654 mg/cm3,0.717 mg/cm3 and 1.135 mg/cm3,respectively.Both greater salt levels in the irrigation water and frequent saline water irrigation led to greater soil bulk density,but poorer soil porosity and less saturated hydraulic conductivity.The saturated hydraulic conductivity decreased with increase in soil bulk density,but increased with improvement in soil porosity.It was noted that the maize height,leaf area index and maize yield gradually decreased with increase in water salinity.The maize yield decreased over 25%and the water use efficiency also gradually declined when irrigated with water containing 6 g/L and 9 g/L salinity levels.However,maize yield following saline water irrigation with 3 g/L decreased less than 20%and the decline in water use efficiency was not significant during the three-year experiment period.The results demonstrate that irrigation with saline water at the level of 6 g/L and 9 g/L in the study area is not suitable,while saline water irrigation with 3 g/L would be acceptable for a short duration together with salt leaching through spring irrigation before sowing.

EFFECT OF GROUNDWATER TABLE CONTROL ON WATER SAVING IRRIGATIONSTRATEGIES IN THE QINGTONGXIA IRRIGATION DISTRICT

This paper focuses on the analysis of the effects of groundwater tablecontrol under different irrigation water amounts on the water and salinity balance and on cropyield. Two experimental areas, the Pingluo and Huinong experimental sites, were selected to collectthe required data. The agro-hydrological model Soil-Water-Atmosphere-Plant (SWAP) was used toanalyse the water flows and salt transport processes for different groundwater levels and irrigationscenarios. Six scenarios, which resulted from different groundwater table regimes combined withdifferent irrigation amounts, were simulated. The results show that high ground-water tables due tothe excessive irrigation are the main cause of the large amount of drainage water and low cropyield; reducing irrigation water without a lower groundwater table will not lead to a largereduction of the drainage water, and will reduce the crop yield even more; to lower the groundwatertable is a good measure to control the drainage water and increase crop yield.

Evaluation of irrigation water salinity and leaching fraction on the water productivity for crops

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.