土-水体系中Hg的垂直迁移

Hg vertical transference in soil-water system w as studied by analyzing Hg vertical distribution in soil column after adding Hg and one of the two leacheates, deionized water or acid rain, into soil column. The results indicated that Hg was hardly transferable in purple soil. About 86% ~ 88% of the total soil Hg was distributed in the top layer (0~2 cm) and no Hg was detected in the leakage when the purple soil column was leached by deionized water and simulated acid rain. But Hg was more movable in yellow soil with only about 20%~22% of the total soil Hg distributed in the top layer (0~2 cm), and about 17%~25% washed out from the soil column by deionized water and simulated acid rain. Increment in soil bulk density could reduce Hg leaching, thus the more the Hg kept in soil, the less the Hg leached into underground water. Deionized water and acid rain almost played the same role in leaching Hg. Bentonite was most efficient in preventing Hg from vertical transferring in the soil column.     

Salt—Water Dynamics in Soils：Ⅲ.Effect of Crop Planting

Through a simulation test conducted with soil columns (61.8cm in diameter) in field condition,effect of crop planting upon the regulation of salt-water dynamics in soils was studied by monitoring of salt-water dynamics in situ,using soil salinity sensors and tensiometers.The results indicated that the amount of water absorbed by crops from the soil was generally larger than the decrement of water consumption from soil surface evaporation reduced by the crop covering the soil surface and improving the soil structure,therefore,under the conditions of crop growing and non-irrigation,water content in soil profile was less than that without crop growing,and the gradient of negative pressure of soil water in soil profile especially in the root zone was enlarged,thus causing the water flowing from subsoils into root zone and increasing the groundwater moving upwards into soil layer via capillary rise,so that the groundwater evaporation increased.Consequently,under the condition of crop growing,the salt was mainly accumulated towards the root zone rather than to the top soil.the accumulating rate of salt in groundwater via capillary rise of soil water to subsoils was increased thereby.     

我国东南部地区红壤表土养分的淋溶及再分布

The leaching and redistribution of nutrients in the surface layer of 4 types of red soils in Southeast China were studied with a lysimeter experiment under field conditions. Results showed that the leaching concentrated in the rainy season (from April to June). Generally, the leaching of soil nutrients from the surface layer of red soils was in the order of Ca > Mg > K > NO₃-N. In fertilization treatment, the total amount of soil nutrients leached out of the surface layer in a red soil derived from granite was the highest in all soils. The uptake by grass decreased the leaching of fertilizer ions in surface layer, particularly for NO₃-N. Soil total N and exchangeable K, Ca and Mg in the surface layer decreased with leaching and grass uptake during the 2 years without new fertilization of urea, Ca(H₂PO₄)₂, KCl, CaCO₃ and MgCO₃. Ca moved from the application layer (0~5 cm) of fertilizer and accumulated in the 10~30 cm depth in the soils studied except that derived from Quaternary red clay. The deficiency of soil exchangeable K will become a serious degradation process facing the Southeast China.     

土壤硼的电化学特征及解吸动力学

Effects of humus fractions (fulvic acid,brown humic acid and grey humic acid) on the leachability and transferring activity of five types of mineral-bound Hg were investigated.Under the acid leaching condition;fulvic acid could promote leachability and vertical transference of all the mineral-bound Hg.Brown humicacid could retard the leaching and trasferring processes of CaCO30-Hg,Fe2O3-Hg,MnO2-Hg and kaolinite Hg but not bentonite-Hg.Grey humic acid could greatly enhance residing ability of the mineral-bound Hg in the soil colum and restrain them from vertical transferring.The effect of humus on leachability and transferring activity on the mineral-bound Hg was closely related to its ability to convert the mineral-bound Hg into orgainc-bound form and the transferbility of the latter in the soil column.The characteristics of the mineral-bound Hg in speciation were the internal factors that determined the extent and rate of the influence of the humus.     

中国南方大棚蔬菜地氮平衡与损失

High rates of fertilizer nitrogen (N) are applied in greenhouse vegetable fields in southeastern China to maximize production;however,the N budgets of such intensive vegetable production remain to be explored.The goal of this study was to determine the annual N balance and loss in a greenhouse vegetable system of annual rotation of tomato,cucumber,and celery at five N (urea) application rates (0,348,522,696,and 870 kg N ha-1 year-1).Total N input to the 0-50 cm soil layer ranged from 531 to 1 053 kg ha-1,and N fertilizer was the main N source,accounting for 66%-83% of the total annual N input.In comparison,irrigation water,wet deposition,and seeds in total accounted for less than 1% of the total N input.The fertilizer N use efficiency was only 18% under the conventional application rate of 870 kg N ha-1 and decreased as the application rate increased from 522 to 870 kg N ha-1.Apparent N losses were 196-201 kg N ha-1,of which 71%-86% was lost by leaching at the application rates of 522-870 kg N ha-1.Thus,leaching was the primary N loss pathway at high N application rates and the amount of N leached was proportional to the N applied during the cucumber season.Moreover,dissolved organic N accounted for 10% of the leached N,whereas NH3 volatilization only contributed 0.1%-0.6% of the apparent N losses under the five N application rates in this greenhouse vegetable system.     

伴随阴离子对马铃薯种植冲击土中钾素固持与淋溶的影响

A column study was carried out to assess the influence of accompanying anions on potassium (K) leaching at potato growing sites with different soil textures (sandy loam and clay loam) in northwestern India. Potassium was applied in the top 15 cm layer of soil column at 30 and 60 mg K kg^-1 through different sources having different accompanying anions (Cl^-, SO₄^2-, NO₃^- and H₂PO₄^-). Maximum K was retained in the top 0--15 cm layer with a sharp decrease in K content occurring in 15--30 cm layer of the soil column. The trend was similar for both levels of applied K as well as frequency of leaching and soil type. The decrease of K content in soil column after four leaching events was maximum in case of Khanaura sandy loam, while only minor decrease was observed in Hundowal clay loam when K was applied at 60 mg K kg^-1, indicating higher potential of clay rich soil to adsorb K. In general, the K leaching in presence of the accompanying anions followed the order of SO₄^2- ≤ H₂PO₄^2- < NO₃^- = Cl^-. Highest 1 mol L^-1 CH3COONH4-extractable K was retained when K was applied along with SO42- and H2PO4- anions, and the least was retained when accompanying anion was Cl^-1. The influence of anions was more pronounced in the light textured soil and at high amounts of K application. Higher levels of K application resulted in higher losses of K, especially in sandy loam soil as observed from the leachate concentration. Among the different K sources, the maximum amount of K leaching was noticed in the soil column amended with KCl. After four leachings, the maximum amount of K leached out was 6.40 mg L^-1 in Hundowal clay loam and 9.29 mg L^-1 in Khanaura sandy loam at 60 mg K kg^-1 of soil application through KCl. These concentrations were lower than the recommended guideline of the World Health Organisation (12.00 mg L^-1).     

Salt-Water Dynamics in Soils: Ⅰ. Salt-Water Dynamics in Unsaturated Soils Under Stable Evaporation Condition

A long term simulation test on salt-water dynamics in unsaturated soils with different groundwater depths and soil texture profiles under stable evaporation condition was conducted.Salinity sensors and tensiometers were used to monitor salt and water variation in soils.The experiment revealed that in the process of fresh groundwater moving upwards by capillary rise in the column,the salts in subsoil were brought upwards and accumulated in the surface soil,and consequently the salinization of surface soil took place.The rate of salt accumulation is determined mainly by the volume of capillary water flow and the conditions of salts contained in the soil profile.Water flux in soils decreased obviously when groundwater depths fell below 1.5m.When there was an interbedded clay layer 30cm in thickness in the silty loam soil profile or a clay layer 100cm in thickness at the top layer,the water flux was 3-5 times less than in the soil profile of homogeneous silty loam soil.Therefore,the rate of salt accumulation was decreased and the effect of variation of groundwater depth on the water flux in soils was weakened comparatively.If there was precipitation or irrigation supplying water to the soil,the groundwater could rarely take a direct part in the process of salt accumulation in surface soil,especially,in soil profiles with an interbedded stratum or a clayey surface soil layer.     

某硫矿重金属分级及土柱淋溶

Fractions of various heavy metals in a sulfidic minespoil were investigated.Column leachine experiment was also conducted to simulate “acid mine drainage“(AMD) from the minespoil.The results show that leaching of heavy metals from the minespoil was extremely significant during the initial water flushing.The amounts of heavy metals leached out dramatically reduced after leaching twice.It is worthwhile to note that in this study,Zn,Mn,Fe,As and Ni in the first leachate exceeded the total amount of each corresponding water-extractable(1:5,soil:water)metal contained in the minespoil sample.This appears to suggest that 1:5 water extraction did not allow accurate estimation of water-leachable concentrations of the above heavy metals.This work has implications for the management of sulfidic minespolis.Acid drainage of great environmental concerns is likely to occur only during heavy rainfall events after substantial soluble and readily exchangeable acid and metals are accumulated in the minespoils.The slow-reacting fractions other than water-soulble and readily exchangeable fractions may pose little environmental hazards.This is particularly true for Pb,As and Ni.     

小麦分泌的有机酸影响钙质土中锌的释放

Rhizosphere drives plant uptake of sparingly soluble soil zinc(Zn).An investigation with three experiments was conducted to study organic acid exudation by two contrasting wheat genotypes(Sehar-06 and Vatan),Zn fractions in 10 different calcareous soils from Punjab,Pakistan,and release of different soil Zn fractions by organic acids.The two genotypes differed significantly in biomass production and Zn accumulation under deficient and optimum Zn levels in nutrient solution.At a deficient Zn level,Sehar-06 released more maleic acid in the rhizosphere than Vatan.Ten soils used in the present study had very different physicochemical properties;their total Zn and Zn distribution among different fractions varied significantly.Zinc release behaviour was determined by extracting the soils with 0.005 mol L-1 citric acid or maleic acid.The parabolic diffusion model best described Zn release as a function of time.Parabolic diffusion model fitting indicated more maleic acid-driven than citric acid-driven soil Zn mobility from different fractions.Cumulative Zn release in six consecutive extractions during 24 h ranged from 1.85 to 13.58 mg kg-1 using maleic acid and from 0.37 to 11.84 mg kg-1 using citric acid.In the selected calcareous soils,the results of stepwise linear regression indicated significant release of Fe-Mn oxide-bounded soil Zn by maleic acid and its availability to the Zn-effcient genotype.Hence,release of maleic acid by plants roots played an important role in phytoavailability of Zn from calcareous soils.     

中国塑料大棚中菜园土盐分含量研究

Field experiments were conducted on three main soils,brown soil,meadow soil and cinnamon soil,of Shandong Province to study the effect of plastic greenhouse gardening on soil salt contents.As compared to the open fields,the soil nutrient contents in the fields under platic greenhouse gardening all incereased significantly,The organic matter,quickly available N and P incereases were extremely significant and the quckly available K increase was also significant.Along with the nutrient incresases the soil salt contents increased clearly in all the soils investigated not only in the top layer but also in the deeper layers being extremely significant in the 0-10 cm lasyer and significant in the 10-40 cm layers .The salt contents in the plastic greenhouses had significant correlations with the soil available nitrogen and phosphorous.Soils with longer plastic greenhouse gardening time tended to have more salt.The platic greenhouse soils contained less CO3^2- and much more NO3^- than the open soils ,which indicated a higher influence of human intervention in plastic greenhouses.Among the constituent ions.Cl^-,NO3^-,Ca^2 and Mg^2 had positive while HCO3^- had negative significant or extremely significant correlations with total salt,with correlation coefficients being 0.66^*,0.80^**,0.92^**,0.80^**and -0.64^*, respectively.Nitrate decreased from the top to deeper layers both in the plastic greenhouses and in the open fields.The ,plastic greenhouse soils contained much more nitrate than the open fields in every layer and even the nitrate contents of the 80-100 cm layer were still several times those of the top layer in the open fields,The main reason for the salt increases was considered to be the inappropriate fertilization and selective absorption of nutrients by plants in the plastic greenhouses.The methods recommended to avoid soil salt increase in the plastic greenhouses were to apply fertilzers rationally according to the soils ,vegetalbes and fertilzer proerties and to adopt a good intercropping or rotation system.     

陕西三种类型土壤剖面硝酸盐累积、分布与土壤质地的关系

研究了陕北黄绵土,关中土与陕南水稻土土壤剖面中硝酸盐的分布与累积,分析了硝酸盐淋移与土壤剖面粘粒含量的关系。结果表明,黄绵土由于粘粒含量少,土壤疏松,氮肥施入土壤后硝化作用速度快,氮素多以硝态氮存在于土壤中,遇到过量的灌溉或降水,容易引起硝酸盐淋失。在米脂的川道地,施肥2个月后,硝酸盐峰值在50cm左右,4个多月后,峰值下移至100cm左右,6个月后,该峰值下降到130cm左右,一年内,硝酸盐的峰值已经消失,分布在130至350cm之间。因此,在黄绵土地区可以灌溉的川道地,氮素损失的主要途径是硝酸盐淋失。关中土,粘粒含量相对较高,硝化作用速度快,但由于在80120cm有一粘化层,阻碍了水分与硝酸盐的向下淋移,使得大部分硝酸盐累积在0100cm土层,其累积量占到0400cm总累积量的64%～74%,而200400cm仅占到7%～13%。而且淋移到100cm以下的硝酸盐,也通过反硝化损失了。陕南水稻土,由于深层土壤水饱和,硝酸盐难以向下淋移,氮素主要累积在土壤表层。由于下层土壤长期处于厌气条件,即使淋移到下层的硝酸盐也通过反硝化作用而损失掉了。     

模拟酸雨和几种低分子量有机酸淋溶对土壤交换性盐基的影响

采用原状土柱进行模拟淋溶实验,比较研究了模拟酸雨和几种低分子量有机酸对红壤交换性盐基的影响。结果表明:与去离子水对照相比,pH 3．5和pH 4．5模拟酸雨淋洗后,0-20 cm土层土壤交换性K 、Na 、 Ca2 和Mg2 含量增加了5．19％-14．65％,而这种增加主要发生在10-20 cm土层。100 μmol／L和10 mmol／L的柠檬酸、苹果酸和草酸淋洗后,0-20 cm土层土壤交换性K 、Na 、Ca2 和Mg2 含量与模拟酸雨淋洗后的结果相差不大,有的层次甚至还要稍低;而在20-50 cm土层则增加了10．42％-96.41％。有机酸淋洗后,土壤交换性盐基的增加受矿物溶解和盐基迁移两方面的影响,而下层的增加可能主要是盐基迁移的影响,由此可见有机酸或许加快了盐基离子向下迁移的速度和土壤酸化过程。     

黄土高原旱地夏季休闲期~(15)N标记硝态氮的去向

夏季休闲是黄土高原旱地小麦常见的蓄纳雨水、恢复地力的措施。随着氮肥用量的增加,一季小麦收获后,旱地土壤剖面累积的硝态氮量不断增加,休闲期间降雨量高,残留硝态氮的去向是值得研究的问题。利用~(15)N标记法研究小麦收获后残留肥料氮在黄土高原旱地(陕西长武)夏季休闲期间的去向,即小麦收获后在微区土壤表层(0~15 cm)施入~(15)N标记的硝态氮肥(30 kg hm~(-2)(以纯氮计),约相当于当地小麦一季作物收获后土壤残留肥料氮量),休闲结束后,采集0~200 cm土壤样品,测定了土壤全氮、硝态氮含量及其~(15)N丰度。结果表明,小麦收获(即休闲开始)时0~200 cm土壤剖面硝态氮累积量在205~268 kg hm-2之间(平均244 kg hm~(-2)),累积量较高。夏季休闲期间降水量为157 mm,属欠水年,但休闲结束后,~(15)N标记肥料氮向下迁移已达80 cm土层,下移深度在45~65cm之间,说明,旱地休闲期间硝态氮的淋溶作用不可忽视。夏季休闲结束后,加入的~(15)N标记肥料氮平均损失率为28%,损失机理值得进一步研究。     

红壤交换性钙、镁和钾的分布及施肥对其影响

A leaching experiment was Carried out with repacked soil columns in laboratory to study the leaching process of a red soil derived from sandstone as affected by various fertilization practices.The treatments were CK(as a control),CaCO3,CaSO4,MgCO3,Ca(H2PO4)2,Urea,KCl,Multiple(a mixture of the above mentioned fertilizers) and KNO3,The fertilizers were added to the bare surface of the soil columns,and then the columns were leached with 120 mL deionized water daily through perstaltic pumps over a period of 92 days,At the end of leaching process,soils were sampled from different depths of the soil profiles ,i.o.,of 92 days,At the end of leaching process,soils were sampled from different depths of the soil profiles,I.e.0-5cm,5-10cm,10-20cm,20-40cm,and 40-60cm,The results showed when applying Ca,Mg,and K to the bare surface of the soil columns,exchangeable Ca^2 ,Mg^2 ,and K^ in the upper layer of the soil profile increased correspondingly,with an extent depending mainly on the application rates of Ca,Mg,and K and showing a downward trend,CaCO3,CaSO4,MgCO3,and Ca(H2PO4)2 treatments had scarcely and effect on movement of exchangeable K^ ,while CaCO3,and CaSO4 treatments singnificantly promoted the downward movement of exchangealble Mg^2 although these two treatments had no obvious effect on leaching losses of Mg,The fact that under Urea treatment,exchangeable Ca^2 and Mg^2 ,were higher as compared to CK treatment showed urea could prevent leaching of exchangeable Ca^2 and Mg^2 ,the obvious downward movement of exchangeable Ca^2 and Mg^2 was noticed in KCl treatment ,In Multiple treatment,the downward movement of exchangeable Ca^2 and Mg^2 was evident,while that of K^ was less evident,Application of KNO3 strongly promoted the downward movement of exchangeable Ca^2 and Mg^2 in the soil profile.     

洛克沙胂在土壤柱中的淋溶迁移

畜禽粪便中残留的兽药进入土壤后的移动性是评价其淋溶能力（对地下水的污染风险）的重要信息。通过土壤柱稳定流实验,考察了不同淋溶剂、粪浸液等对洛克沙胂在不同深度（0～20、20～50、50～80 cm）灰潮土中的迁移行为影响。结果表明,水、0.01mol.L^-1 CaCl2、0.01 mol.L^-1 EDTA-Na2淋溶剂,对不同深度土壤柱中洛克沙胂的淋溶穿透曲线（BTCs）呈现不同程度的不对称性,在不同深度土壤柱中对洛克沙胂的淋出率分别为：水为92.3%～97.1%,0.01 mol.L^-1 CaCl2为71.0%～84.9%,0.01 mol.L^-1 EDTA-Na2为75.4%～91.2%;土壤柱先用粪浸液通过后,洛克沙胂的穿透曲线峰时间均有不同程度的提前,淋出率均有增加,在不同深度土壤柱中的淋出率分别为：水为96.4%～110.4%,0.01 mol.L^-1 CaCl2为94.5%～106.8%,0.01 mol.L^-1 EDTA-Na2为90.8%～103.2%。说明洛克沙胂随粪便进入土壤后可较快地淋溶迁移,可进入地表水和地下水中,对水环境质量的影响较大。     

Chemical properties of acid soil treated with coal combustion by‐products and leached

Abstract

Application of coal combustion by‐products (CCBs) to acid soils can have beneficial or detrimental effects. A column study was conducted to determine the effects of CCBs on mitigating acid soil properties after leaching with 138 cm deionized water. Columns containing 105 cm acidic Lily soil (Typic Hapludult) had mixed in the top 15 cm the following treatments (g/kg soil): no CCB or limestone (check); dolomitic limestone (lime) at 3.98; high‐calcium sulfate (CaSO₄) flue gas desulfurization (FGD) by‐product (BP) at 15.88; combination of lime+FGD at rates given; high‐CaSO₄ FGD BP enriched with Mg (FGD+Mg) at 15.88; and fluidized bed combustion (FBC) BP at 6.45. After being leached for 39 days, the columns of acid soil treated with high‐CaSO₄ by‐products showed higher subsurface pH, calcium (Ca), and sulfur (S) and lower aluminum (AI) and manganese (Mn). In contrast, the lime alone treatment had little effect on subsurface soil properties. Use of dolomitic limestone to supply magnesium (Mg) in conjunction with the CaSO₄ treatments was more effective than supplementation with Mg(OH)₂, where97% of the added Mg leached from the top layer. Substances leached from the CCBs studied were effective in reducing problems associated with subsurface soil acidity.     

减氮配施有机物质对土壤氮素淋失的调控作用

采用室内土柱模拟试验方法,研究不同氮肥施用下1m土体中氮素的分布和移动特征,揭示土壤氮素动态变化规律。结果表明:FN(农民习惯施无机氮用量)、RN(根据土壤养分供应和作物需求确定的推荐无机氮用量)显著增加了土壤上层NH_4^+-N和NO_3^--N向下层淋失。RN+HA(与推荐无机氮纯养分相等的锌腐酸尿素)和RN40%+OMB(推荐无机氮肥减60%基础上配施自制有机调理物质)可延长上层土壤NH_4^+-N峰值出现时间,降低下层NH_4^+-N。淋溶结束后,等氮量下增施HA较RN降低60cm以下NH_4^+-N残留29.7%～54.2%;降低60—80cm NO_3^--N累积17.4%。RN40%+OMB处理无机氮肥用量最小,0—20cm的NH_4^+-N最高,40—100cm稳定在2.0mg/kg左右;0—20,20—40cm土层NO_3^--N较RN+HA增加12.3%和2.0%,显著降低40cm以下NO_3^--N残留。RN+HA和RN40%+OMB较RN的土壤总无机氮残留分别减少7.4%和20.2%,降低表观淋失率。因此,RN40%+OMB可较好地抑制氮素下移,降低氮素淋失风险,为减少氮素淋失、明确合理氮肥施用方式提供科学依据。     

Carbohydrate and amino acid composition of dissolved organic matter leached from soil

Low molecular weight organic substances (LMWOS) in soil and soil solution include mainly amino acids, carboxylic acids, and carbohydrates. Due to their high bioavailability they play a crucial role in the cycles of C and nutrients in soils. The variety of soil processes that involve LMWOS requires identifying their composition to elucidate reactions and transformations. In most studies, LMWOS are extracted under artificial conditions, e.g. batch experiments, which may overestimate the actual concentrations. This study measures the composition of carbohydrates and amino acids in solution of a Haplic Luvisol leached in a column experiment. A combined system for simultaneous leaching and blowout of CO₂ was used to estimate LMWOS decomposition. ¹⁴C-labeled glucose was added as a highly sensitive tracer to control the efficiency of the LMWOS extraction by leaching and to estimate LMWOS decomposition during leaching. High performance liquid chromatography (HPLC), optimized for soil extracts, was used to analyze LMWOS composition. For HPLC optimization, different preparations of leached solutions (filtration vs. centrifugation, and drying vs. no-drying) were compared. For sugar determination, drying had no influence on the solution concentrations. In contrast, amino acid concentrations significantly decreased by drying LMWOS eluted substances. Combining the HPLC identification of eluted substances with ¹⁴C tracer application revealed that about 5% of the glucose could be leached unchanged within 786 min (13.1 h), whereas about 84% remained in the soil, 9% were decomposed to CO₂, and 2% were transformed to other LMWOS and recovered in the soil solution. The total amino acid concentration (TAC) in soil solution was about 8.2 μmol l⁻¹, dominated by alanine (14.4% of TAC), glycine (13.4%), glutamic acid (9.9%), serine (9.4%), and leucine (9.3%). The total carbohydrate concentration was about 2.4 μM, dominated by glucose (29.9%), glucuronic acid (26.8%), and galacturonic acid (17.3%). Ratios of hexoses to pentoses, amino sugars glucosamine to galactosamine, and neutral sugars to uronic acids were determined. All three parameters pointed to the dominant influence of plants as the source of LMWOS in the leached soil solution. Within the small contribution of microorganisms, bacteria dominated over fungi. These used biomarker ratios as well as LMWOS concentrations differed widely from the ones obtained with conventional batch extraction. More research is necessary to evaluate the application of these biomarkers to soil solutions.     

复合隔层对河套灌区盐碱土水盐运移的影响

河套灌区盐渍农田分布广、肥力质量差、生产力水平低,严重威胁粮食安全。为研究秸秆–保水剂复合隔层对河套灌区盐碱土的控盐及节水效果,通过室内土柱模拟试验,设置常规灌溉水量(10 L)和节水20%灌溉水量(8 L)2种灌溉水量下的2种隔层(秸秆隔层和复合隔层)以及对照组处理,对比研究了复合隔层与秸秆隔层在节水条件下对土壤水分入渗过程、蒸发过程以及盐分变化规律的影响。研究结果表明:入渗过程中,两种隔层均能延缓水分入渗,提高淋盐效果,相比秸秆隔层,复合隔层处理水分入渗时间延缓14.47%,对0～40 cm土层淋盐效果提升34.86%。蒸发过程中,复合隔层能够通过内部保水剂缓慢释水,对20～40 cm土层补水,其20～40 cm土层含水率较秸秆隔层提升10.90%～90.61%。节水20%的条件下,复合隔层处理在0～40 cm土层的灌溉淋盐效果及蒸发过程中的保水抑盐效果优于未进行节水处理的对照组。综合来看,秸秆–保水剂形成的复合隔层其淋盐效果、保水抑盐效果均优于秸秆隔层,在节水条件下仍具有较好的保水控盐效果。本研究可为河套灌区节水型盐碱障碍消减研究提供依据和参考。