Water and nitrogen transport characteristics of single-line interference infiltration under film hole irrigation with muddy water and fertilizer

Based on the experimental data,this study investigated the effect of sand content of muddy water on water and nitrogen transport characteristics of the single-line interference infiltration under film hole irrigation with muddy water and fertilizer.The relationship between the single-line interference infiltration parameters,the sand content,the wetting front movement distances,and the sand content were all established.The model of the cumulative infiltration volume of per unit film pore area,the vertical and horizontal wetting front movement distance of the free surface,and the wetting front movement distance of the interference center with sand content and infiltration time were proposed.Reveal the law of the change of soil water content and the distribution of NO_(3)^(-)-N content based on different muddy water sand content.The results indicate that at the same infiltration time,as the muddy water sand content increases,the cumulative infiltration volume per unit pore area decreases.The infiltration index of the free infiltration and the single-line interference vary little when the sand content increases,mainly are around 0.64 and 0.58.The relationship between infiltration parameters a,b and the sand content is linear function.At the same location,the more the sand content,the smaller the wetting front movement distance in free surface and the single-line interference surface,the less the NO_(3)^(-)-N content.

Green High-yield and High-efficiency Cultivation Techniques of Integrated Management of Water and Fertilizer for Maize under Mulch Drip Irrigation

The green high-yield and high-efficiency cultivation techniques of integrated management of water and fertilizer for maize under mulch drip irrigation are described from the aspects of high yield target of maize and its component factor indexes,pre-sowing preparation,sowing,post-sowing management,field management at the seedling stage,integrated management of water and fertilizer for target yield of maize,rational application of micro-fertilizer,comprehensive prevention and control of diseases and pests,timely harvest,etc.,in order to provide a reference for agricultural technicians,maize farmers and maize industry development in northern Xinjiang.

Growth, Yield and Water Use Effeciency of Forage <i>Sorghum</i>as Affected by Npk Fertilizer and Deficit Irrigation

Drought stress (DS) is an important limiting factor for crop growth and production in some regions of the world. Limitation in water availability precludes optimal irrigation in some production regions. Therefore, investigations on the interaction of other factors to mitigate the DS to varying degree are important. Two field experiments were conducted in the experimental farm of the National Research Centre, Shalakan, Kalubia Governorate, Egypt, during 2004 and 2005 summer seasons to evaluate the interactions between N, P, K rates and optimal vs. deficit irrigation regimes on biomass yield as well as water use efficiency (WUE) of forage sorghum. Omission of the 4th irrigation significantly decreased the biomass of sorghum c.v. Pioneer, as compared to that of the plants receiving optimal irrigation or subject to omission of the 2nd irrigation. The biomass yield increased with an increase in NPK fertilizer rates. Plant height and leaf area also decreased by omitting the 2nd irrigation as compared to that of the plants under optimal irrigation, and further declined with omission of the 4th irrigation. The biomass of the plants (dry weight basis) that received the high N, P, K rates was greater by 26%, 29%, and 35% as compared to that of the plants that received no N, P, K fertilizers, under optimal irrigation, omission of the 2nd, and omission of the 4th irrigation, respectively. The corresponding increases in water use efficiency (based on fresh weight yield) were 37%, 42%, and 55%.

Evaluation of photosynthesis, physiological, and biochemical responses of chickpea (Cicer arietinum L. cv. Pirouz) under water deficit stress and use of vermicompost fertilizer

One goal in the face of drought stress conditions is to increase growth and yield through the reduction of negative effects of stress. Vermicompost can play an effective role in plant growth and development and in reducing harmful effects of various environmental stresses on plants due to its porous structure, high water storage capacity, having hormone-like substances, plant growth regulators, and high levels of macro and micro nutrients. This study considered the physiological, biochemical, and photosynthetic responses of the chickpea to different combinations of vermicompost and water stress in a greenhouse environment. Two factors were involved, addition of vermicompost to soil at four ratios： control （100 wt% （weight percentage） sol0; 10 wt% vermicompost＋90% soil; 20 wt% vermicompost＋80 wt% soil; 30 wt% vermicompost＋70 wt% soil weight percentage, and treatment of water stress at three levels including 75, 50, and 25% of field capacity. The results showed that vermicompost had a significant effect on all traits under stress and non-stress conditions. Application of vermicompost in soil, especially at the levels of 20 and 30 wt% significantly increased all studied traits under non-stress conditions. Under moderate stress conditions, vermicompost at 30 wt% treatment resulted in a significant increase in the photosynthetic pigments, CO2 assimilation rate, internal leaf CO2 concentration, transpiration, the maximal quantum yield of photosystem II （PSII） photochemistry （FJF）, concentrations of Ca and K in root and leaf tissues, proline and soluble protein contents in root tissues. Peroxidase （POX） and catalase （CAT） enzyme activities decreased significantly with increasing proportions of vermicompost, but the activity of superoxide dismutase was not significantly different. In conclusion, the above results showed that vermicompost fertilizer had a positive effect on physiological, biochemical, and photosynthetic responses of chickpea under non-stress and moderate stress conditions, but no positive effect was determined under severe water stress.

Effect of water and fertilizer coupling optimization test on water use efficiency of rice in black soil regions

How to improve the water use efficiency of rice in black soil regions was studied. The black soil region in paddy fields was chosen as the research object. The research showed the fertilizer coupling mathematical model with N,P,K,irrigation water( W) and water use efficiency( WUE),which was set up under the condition of controlled irrigation with quadratic D- 416 optimized saturation design. The results show that the decending order of single factor' s influence on the WUE was N,K,P and W. All the interactions between N&P,N&K,N&W,K&P,P&W and K&W on the WUE were raised initially,and when reached a certain value,they began to decline. The decending order of each interaction on the WUE was K&P,K&W,N&K,N&P,P&W and N&W. When the WUE was targeted within 1. 8- 2. 5 kg / km^3,an optimized proportion plan was obtained in the 95% confidence interval,i. e. N 87. 76- 103. 32 kg / hm^2,K_2 O 52. 37- 66. 53 kg / hm^2 and P_2O_536. 80- 46. 71 kg / hm^2. Furthermore,the late tillering of the soil moisture content was 70. 07%- 72. 57% of the saturated moisture content.

Responses of leaf water potential and gas exchange to the precipitation manipulation in two shrubs on the Chinese Loess Plateau

Regulation of leaf gas exchange plays an important role in the survival of trees and shrubs under future climate change. However, the responses of leaf water potential and gas exchange of shrubs in semi-arid areas to the precipitation alteration are not clear. Here, we conducted a manipulated experiment with three levels of precipitation, i.e., a control with ambient precipitation, 50% above ambient precipitation(irrigation treatment), and 50% below ambient precipitation(drought treatment), with two common shrubs, Salix psammophila C. Wang & C. Y. Yang(isohydric plant, maintaining a constant leaf water potential by stomatal regulation) and Caragana korshinskii Kom.(anisohydric plant, having more variable leaf water potential), on the Chinese Loess Plateau in 2014 and 2015. We measured the seasonal variations of predawn and midday leaf water potential(Ψpd and Ψmd), two parameters of gas exchange, i.e., light-saturated assimilation(An) and stomatal conductance(gs), and other foliar and canopy traits. The isohydric S. psammophila had a similar An and a higher gs than the anisohydric C. korshinskii under drought treatment in 2015, inconsistent with the view that photosynthetic capacity of anisohydric plants is higher than isohydric plants under severe drought. The two shrubs differently responded to precipitation manipulation. Ψpd, An and gs were higher under irrigation treatment than control for S. psammophila, and these three variables and Ψmd were significantly higher under irrigation treatment and lower under drought treatment than control for C. korshinskii. Leaf water potential and gas exchange responded to manipulated precipitation more strongly for C. korshinskii than for S. psammophila. However, precipitation manipulation did not alter the sensitivity of leaf gas exchange to vapor-pressure deficit and soil moisture in these two shrubs. Acclimation to long-term changes in soil moisture in these two shrubs was primarily attributed to the changes in leaf or canopy structure rather than leaf gas exchange. These findings will be useful for modeling canopy water-carbon exchange and elucidating the adaptive strategies of these two shrubs to future changes in precipitation.

Distribution Characteristics of the Heavy Metal Cd in the Irrigation Water-Cultivated Soil-Fertilizer-Crop Ecosystem

Shuangqiao Countryside of Neijiang City in hilly ground area in the midland of Sichuan Province was chosen as the study geographic area to survey and analyze the content distribution characteristics of the Cd in the irrigation water,ground water mud,surface layer cultivated soil,profile soil and the fertilizer which were often used in the locality,and in different crops set earth,fructification as well. The results showed that the content of Cd in the irrigation and ground water mud respectively comply with the national agriculture use irrigation standard and the contamination control standard value in agriculture use mud ( GB4284-84) respectively. The average contents in the surface cultivated soil and each layer of soil profile are all above the background level of Chengdu economic region ( 44% ) ,referring to a large scale pollution risk. The average value of Cd element in fertilizer was 1. 81 μg / g,which was higher than the third class standard of national soil environment quality; The average content of Cd element in the crops' set earth was 0. 410-0. 439 μg / g,which was higher than the second class standard of national soil environment quality and there was a measure of cumulation; The average values of Cd in crops' fructificationwas all below the primary standard of national soil environment quality,and the bioamplification coefficient sorting was CF( Cdpeanut) > CF( Cdcitrus) > CF ( Cdrice) > CF( Cdcorn) . Irrigation water had little influence on the soil Cd pollution,where fertilizer using was closely related to the Cd pollution in the surface cultivated soil in the survey area and had a certain influence on the Cd cumulation in the crops. The sorption and enrichment of crops' set earth and fructification was obviously different.

Study of the Inhibitor Scaling Effect of the Agricultural Water by a Phosphate Fertilizer

The localised irrigation or drop by drop system is a technique which makes it possible to save water, because it ensures a balanced and efficient distribution of water and an effective fertilization. However, this ferti-irrigation system is facing a number of problems hindering the agricultural development. The lack of uniformity of the localised irrigation was observed and found out that it is due to chemical clogging of drippers. Considering the complexity of the composition of the natural water used in micro-irrigation, we started our study by examining the effectiveness of the inhibitor on pure calco-carbonic water with 40°F, and then moved to explore the natural water of the agricultural region. The Legrand-Poirier-Leroy method allowed us to determine the position of the irrigation water compared to calco-carbonic balance. LCGE (abbreviation of “Laboratory of Chemistry and Environmental Engineering”) technique, based on the accelerated formation of calcium carbonate deposit under the effect of a degasification of studied water, enabled us to evaluate the scaling power of this water of irrigation either with or without inhibitor. The experimental results showed the following: in the case of pure calco-carbonic water with 40?F and of natural water, the addition respectively of 2 mg/L and 2.25 mg/L of phosphate fertilizer completely inhibits the precipitation of calcium carbonate under the conditions of the experiment.

Oxalate Content of Miner’s Lettuce Irrigated with Water or Fertilizer Solutions

The total, soluble and insoluble oxalate contents of the small, large and cauline leaves and small and large stems of miner’s lettuce (Claytonia perfoliata ) plants which had been irrigated with tap water or a soluble fertilizer were extracted and measured using HPLC chromatography. Overall, all plant parts of miner’s lettuce analyzed contained high levels of total and soluble oxalates;however plants irrigated with fertilizer contained lower levels of oxalates compared with plants irrigated with water. On a dry matter basis, the small leaves contained higher levels of total oxalate when compared to the total oxalate in the large leaves. Soluble oxalate in the leaves of plants irrigated with water ranged from 2.6 to 7.5 mg/100g dry matter (DM) and was significantly higher (P < 0.05) than the leaves of the fertilizer-watered plants, which ranged from 1.8 to 2.8 mg/100g DM. The soluble oxalate in the small and large stems of the fertilizer-watered plants ranged from 1.20 to 1.5 mg/100g DM and was significantly lower (P < 0.05) than the water-treated small and large stems, which ranged from 3.75 to 4.4 mg/100g DM. It is recommended that the leaves of miner’s lettuce should be consumed in moderation.

Fertilizer drawn forward osmosis as an alternative to 2nd pass seawater reverse osmosis: Estimation of boron removal and energy consumption

Agriculture is the largest consumer of freshwater.Desalinated seawater is an important alternative water source for sustainable irrigation.However,some issues of the current desalination technology hinder its use for agriculture irrigation,including low boron removal and high energy consumption.This study systematically explored the feasibility of employing fertilizer drawn forward osmosis(FDFO)as an alternative to 2nd pass reverse osmosis(RO)by considering the boron removal performance and specific energy consumption(SEC).Different operating conditions were investigated,such as the boron and NaCl concentrations in feed solution(FS),draw solution(DS)concentration,pH,the volume ratio of FS to DS,membrane orientation,flow rate,and operating temperature.The results indicated that a low boron concentration in FS and high DS pH(pH=11.0)decreased the boron solute flux,and led to low final boron concentration in the DS.The other operating conditions had negligible influence on the final DS boron concentration.Also,a lower flow rate and higher specific water flux with certain permeate water volumes were conducive to reducing the SEC of the FDFO process.Overall,our study paves a new way of using FDFO in irrigation,which avoids the phytotoxicity and human health risk of boron.The results show the potential of FDFO as an alternative to 2nd pass RO for irrigation water production.

Effects of drip irrigation modes on growth and physiological characteristics of Arabica coffee under different N levels

The objective of this study was to obtain the water-saving and efficient production mode of Arabica coffee. The effects of three drip irrigation modes,conventional drip irrigation( CDI),alternate drip irrigation( ADI) and fixed drip irrigation( FDI) on growth,photosynthetic characteristics,biomass accumulation and irrigation water use efficiency of Arabica coffee were investigated under three nitrogen levels,high nitrogen( NH),middle nitrogen( NM) and low nitrogen( NL). The results show that there was a significant Logistic curve between the plant height,the stem diameter of Arabica coffee and growth days. Compared with CDI,ADI had no significant effects on leaf net photosynthetic rate,stomatal conductance,instantaneous water use efficiency and biomass accumulation above ground of Arabica coffee,while FDI decreased significantly,ADI and FDI increased irrigation water use efficiency by 50. 59% and 32. 85%,respectively. Compared with NH,with the reduction of N application rate,net photosynthetic rate,stomatal conductance,biomass accumulation above ground and irrigation water use efficiency decreased by 6. 81%-12. 30%,13. 70%-22. 69%,9. 61%-16. 67% and 9. 78%-15. 64%,respectively. Compared with CDINH,ADINHdecreased net photosynthesis rate and the stomatal conductance not significantly,other treatments decreased by 9. 16%-19. 22%,14. 49%-32. 91%,and decreased biomass accumulation above ground by 8. 26%-27. 34% except ADINH,and increased irrigation water use efficiency by 16. 46%-60. 95% except CDINMand CDINL. Therefore,alternate drip irrigation under high N level( ADINH) is the best water and nitrogen coupling mode of young Arabica coffee tree for water efficiency.

The effects of aeration and irrigation regimes on soil CO_2 and N_2O emissions in a greenhouse tomato production system

Aerated irrigation has been proven to increase crop production and quality, but studies on its environmental impacts are sparse. The effects of aeration and irrigation regimes on soil CO2 and N2O emissions in two consecutive greenhouse tomato rotation cycles in Northwest China were studied via the static closed chamber and gas chromatography technique. Four treatments, aerated deficit irrigation（AI1）, non-aerated deficit irrigation（CK1）, aerated full irrigation（AI2） and non-aerated full irrigation（CK2）, were performed. The results showed that the tomato yield under aeration of each irrigation regime increased by 18.8% on average compared to non-aeration, and the difference was significant under full irrigation（P〈0.05）. Full irrigation significantly increased the tomato yield by 23.9% on average in comparison to deficit irrigation. Moreover, aeration increased the cumulative CO2 emissions compared to non-aeration, and treatment effects were significant in the autumn-winter season（P〈0.05）. A slight increase of CO2 emissions in the two seasons was observed under full irrigation（P〉0.05）. There was no significant difference between aeration and non-aeration in soil N2O emissions in the spring-summer season, whereas aeration enhanced N2O emissions significantly in the autumn-winter season. Furthermore, full irrigation over the two seasons greatly increased soil N2O emissions compared to the deficit irrigation treatment（P〈0.05）. Correlation analysis indicated that soil temperature was the primary factor influencing CO2 fluxes. Soil temperature, soil moisture and NO3^- were the primary factors influencing N2O fluxes. Irrigation coupled with particular soil aeration practices may allow for a balance between crop production yield and greenhouse gas mitigation in greenhouse vegetable fields.

Effects of water and nitrogen coupling on growth,physiology and yield of rice

Water and nitrogen fertilizer are two essential factors for quality and yield formation of rice.Experimental study was carried out to investigate the effects of water and nitrogen fertilizer coupling on yield-related factors,such as growth(height),physiological indicators(chlorophyll and leaf area index(LAI))and yield composition indicators(productive panicles,thousand grain weight and total grains per panicle).Results showed that,the height difference under two irrigation regimes was not significant,and it showed no difference until the tillering stage(p>0.05).The water control method for controlled and mid-gathering irrigation(CMI)was favorable for nutrients converting to rice grain.Meanwhile the height difference for CMI and conventional irrigation(CVI)was the biggest at 80 d after rice transplantation.Variance analysis showed the effect of fertilization on height was significant(p<0.05).With organic fertilizer application,it could control plant growth and promote the nutrients converting to the panicle.The change curve of LAI was similar to chlorophyll content.Organic fertilizer application could not only promote chlorophyll content and LAI,but also delay leaf fading and promote yield.Nitrogen fertilizer factors showed significant difference on rice yield,compared to irrigation regimes showing no significance.Considering the irrigation and fertilizer factors together,the interaction was significant.The descending orders for the effects of water and nitrogen on rice yield were fertilizer,water and fertilizer,water.Regression analysis showed that the productive panicles and total grains per panicle of rice were extremely significant on rice yield,and the direct effect of total grains per panicle on yield was greater than that of productive panicle.This study results could provide theoretical basis for water and nitrogen management to improve rice production.

Effect of Irrigation and Fertilization on Population Structure and Yield of Wheat

[Objectives] This study was conducted to investigate the effects of irrigation and fertilization on population structure and yield of wheat.[Methods]With Shannong 29 as an experimental material,the effects of irrigation and fertilization on population,dry matter accumulation and yield of wheat were studied.[Results]Integrated water-saving irrigation and fertilization of ridged field was the best with the highest population,dry matter accumulation and yield of wheat.[Conclusions]This study provides a theoretical basis for high-yield and high-efficiency wheat production with saved water and fertilizers.

基于数值分析法的水肥一体机设计研究

以进一步提升水肥一体机的智能性、数字性作业为目标,针对整机的灌施精准性要求展开设计。充分考虑水肥一体机的运用特点和结构组成,结合水肥的参数融合关系,建立用于水肥一体机准确控制作业的状态方程模型,设计以数值分析处理函数为核心的软件控制模块,搭建同步动作实施的硬件执行平台。展开多作物的灌施作业试验,结果表明:基于数值分析方法的水肥一体机系统架构设计合理,数值分析算法融入有效,整机试验的数值计算准确率可达98.00%以上;水肥混合均匀有度,整体管路灌施顺畅,灌施指令准确率可达99.00%以上,整机灌施效率较高,充分验证了数值分析方法应用的正确性与优越性,可以促进类似农机装备与高等数学多维度融合。

补灌条件下增施有机肥对小麦-玉米产量及水分利用效率的影响

探讨补灌条件下增施有机肥对小麦、玉米产量、耗水量和水分利用效率的影响,为豫中补灌区合理利用水肥资源、小麦-玉米高产高效生产提供理论依据和技术支撑。2018-2020年进行田间定位试验,设3个灌水水平:不灌溉(W0),补灌1次(W1)(拔节期)、补灌2次(W2)(拔节期,抽穗-扬花期),每次灌水450 m^(3)/hm^(2)。设5个施肥模式:不施肥(N0)、纯氮210 kg/hm^(2)(N1)、纯氮300 kg/hm^(2)(N2)、纯氮210 kg/hm^(2)+有机肥1 500 kg/hm^(2)(N3)、纯氮300 kg/hm^(2)+有机肥1 500 kg/hm^(2)(N4)。(1)连续2 a灌水措施(W)、施肥模式(N)和灌水×施肥交互作用对小麦、玉米产量和全生育期耗水量均具有极显著影响,且低氮(N1)条件下增施有机肥有利于提高小麦、玉米产量和水分利用效率,其中小麦产量增加了1.75%~17.11%,玉米产量增加了2.42%~12.66%。(2)连续2 a 3种灌水水平条件下,N0处理小麦、玉米产量和水分利用效率低于或显著低于其他处理。(3)2019年小麦、玉米产量均以W1N4最高,分别为11 865.53 kg/hm^(2)和11 662.82 kg/hm^(2);2020年W2N4小麦处理产量最高,W1N3处理玉米产量最高。(4)小麦全生育期耗水量差异显著,连续2 a补灌2次处理的小麦、玉米全生育期耗水量均高于不灌溉相应处理。(5)2019年小麦、玉米水分利用效率均以W2N0最低,2020年W1N0小麦水分利用效率处理最低,W2N0处理次之,W2N0处理玉米水分利用效率最低。补灌或增施有机肥对小麦、玉米产量具有极显著影响,对小麦、玉米水分利用效率有一定积极影响。豫中补灌区推荐适宜小麦-玉米灌溉施肥模式为:小麦、玉米拔节期各补灌1次,施用纯氮300 kg/hm^(2)+有机肥1 500 kg/hm^(2)(氮肥底追比为底施∶拔节肥=7∶3)。

灌水施氮和缩节胺用量对南疆棉花产量品质和水肥利用效率的影响

为研究灌水量、施氮量和缩节胺用量对棉花籽棉产量、纤维品质和水肥利用效率的交互影响,于2020年和2021年在南疆库尔勒地区开展大田试验,设置3个灌水量(W1:60%ETc,W2:80%ETc,W_(3):100%ETc,ETc为作物蒸发蒸腾量),4个施氮量(N0:0,N200:200 kg/hm^(2),N_(300):300 kg/hm^(2),N_(400):400 kg/hm^(2))和2个缩节胺用量(D_(1):120 g/hm^(2),D_(2):240 g/hm^(2))。结果表明:灌水量、施氮量和缩节胺用量对籽棉产量、水分利用效率、肥料偏生产力和部分纤维品质指标影响显著(P<0.05)。灌水量、施氮量和缩节胺用量三者交互作用对肥料偏生产力和纤维品质影响显著(P<0.05)。株高、叶面积指数和干物质量也受灌水量、施氮量和缩节胺用量三者交互作用影响。W_(3)N_(300)D_(2)处理籽棉产量最高(2020年为7578 kg/hm^(2),2021年为7173 kg/hm^(2)),W1N_(400)D_(1)处理水分利用效率和W_(3)N0D_(2)处理肥料偏生产力最高,W_(3)N_(400)D_(2)处理的纤维长度、纤维强度和马克隆值均获得较大值,纤维品质最佳。基于TOPSIS综合评价方法对棉花产量品质和水肥利用效率进行综合评价,100%ETc灌水量、300 kg/hm^(2)施氮量和240 g/hm^(2)缩节胺用量组合最优,可作为南疆棉花适宜的水氮和化控管理模式。研究结果可为南疆棉花水肥高效利用提供理论依据和科学指导。

微咸水-腐植酸肥耦合滴灌条件下钙镁离子质量浓度对灌水器堵塞的影响

【目的】探明腐植酸肥施用条件下不同钙镁离子质量浓度对灌水器堵塞物质形成的影响效应与作用机制。【方法】以微咸水中钙镁离子耦合腐植酸肥滴灌为研究对象,选取4种不同额定流量(1.6、1.1、1.4、1.75 L/h)的非压力补偿内镶贴片式灌水器(FE1—FE4),其中设置3组钙离子质量浓度微咸水处理,离子质量浓度分别为100、150、200 mg/L(G1、G2、G3),3组镁离子质量浓度微咸水处理,离子质量浓度分别为100、150、200 mg/L(M1、M2、M3),以地下微咸水灌溉为对照(CK),研究不同离子质量浓度的灌水器平均流量(Dra)、滴灌系统灌水器的堵塞率分布、灌水器堵塞物质干质量(DW)动态变化规律,并分析了灌水器内部堵塞物质矿物组分。【结果】与CK相比,G1、G2、G3、M1、M2、M3处理的Dra分别降低了21.58%~29.68%、35.02%~39.71%、45.62%~55.68%、14.25%~20.41%、24.89%~45.69%、35.22%~56.75%,堵塞物质干质量分别增加了124.62%~178.49%、174.23%~230.33%、235.59%~270.09%、67.14%~120.28%、136.96%~191.18%、203.54%~213.35%。与G1、G2、G3处理相比,质量浓度相同镁离子处理M1、M2、M3处理的堵塞物质干质量分别降低了16.41%~27.26%、4.77%~13.60%、6.82%~15.34%。【结论】钙镁离子质量浓度的增加均显著加剧了灌水器的堵塞;在相同离子质量浓度条件下,镁离子处理显著减少了灌水器内堵塞物质的总量,因此镁离子在一定程度上能够降低灌水器堵塞风险。

马铃薯节水灌溉技术研究进展

马铃薯是我国第四大粮食作物,马铃薯高效生产对保障国家粮食安全具有重要意义。马铃薯需水量大,生育期间的降水量无法满足其正常水分需求,因此对灌溉水的依赖度高。然而,我国淡水资源短缺,马铃薯生产中存在灌溉水管理粗放、节水灌溉制度不合理、水分利用效率低等问题,亟需探索马铃薯节水高效灌溉技术体系。本文从需水规律、灌溉方式、灌溉制度等方面综述了马铃薯灌溉技术的研究现状和存在的问题,对我国马铃薯节水灌溉技术需要进一步研究的问题进行了展望,以期丰富马铃薯高效用水理论,为马铃薯稳定生产提供技术支撑。

滴灌不同浓度水溶肥对樱桃产量和品质的影响

以辽宁主栽的“美早”和“砂蜜豆”两个樱桃品种为试材,通过设置不同浓度大量元素水溶肥滴灌处理,探究不同施肥浓度对樱桃产量和果实品质的影响。结果表明:800倍液滴灌施肥处理的效果最佳,两品种单果重分别为13.86 g、13.50 g,单株产量分别为30.14 kg、29.44 kg,可溶性固形物含量分别为18.73%、18.68%,维生素C(Vc)含量分别为45.55 mg·kg^(-1)、44.90 mg·kg^(-1),酸度含量分别为0.80%和0.83%。