地下水位波动对不同施氮量农田土壤硝态氮运移影响

明确地下水位波动对农田土壤剖面和地下水NO_3~--N运移的影响,可为减少土壤氮素淋失、降低地下水硝酸盐污染风险提供依据。本研究采用大型土柱温室种植甘蓝,研究2种水位波动(水位不变、水位每隔10 d波动20 cm)和3种施氮量[0 kg(N)·hm~(-2)、225 kg(N)·hm~(-2)、450 kg(N)·hm~(-2)]对土壤含水量、土壤溶液NO_3~--N浓度、地下水NO_3~--N浓度和作物产量的影响。结果表明,水位波动和施氮肥对NO_3~--N运移的影响与土壤剖面深度有关。0～20cm包气带土壤NO_3~--N含量受施氮量影响,过量施氮肥[450kg(N)·hm~(-2)]导致该剖面NO_3~--N累积。20～60cm水位波动带土壤NO_3~--N含量受施氮量和水位波动的共同作用:施氮量增加提高NO_3~--N含量;水位波动降低剖面土壤NO_3~--N含量,水位上升和下降均促进土壤NO_3~--N随着水流运动向下层迁移;剖面土壤硝态氮含量高,增加NO_3~--N进入地下水的风险。60～80 cm淹水区剖面土壤NO_3~--N含量较低。作物产量受水位波动影响不显著。在地下水位埋深较浅的农业区进行氮素污染防控时,不可忽视水位波动对NO_3~--N运移的影响。     

层状包气带黏土层厚度对硝态氮迁移的影响

层状包气带结构中黏土层对污染物进入地下水具有阻滞作用,黏土层的厚度对硝态氮(NO_3~--N)在包气带迁移中的淋失、累积以及反硝化作用等具有非常重要的影响,而目前关于这方面的研究还不足。该研究通过设置高度为40 cm、砂土与黏土层厚度比分别为3∶1,1∶1,1∶3的"上粗下细"型以及全黏土型的4组填充土柱,采用稳定浓度的定水头淋滤试验,研究黏土层厚度不同的土柱NO_3~--N溶液入渗过程、土壤NO_3~--N淋滤、累积和反硝化特征,进而阐明层状包气带黏土层厚度对NO_3~--N迁移的影响。结果表明:湿润锋运移深度和累积入渗量与入渗时间的关系在溶液穿越砂黏土层界面前后由非线性趋于线性,累积入渗量随黏土层厚度增加而显著减小(P0.05);当土柱内黏土层厚度达到40 cm时,其对NO_3~--N淋滤的阻滞作用明显强于黏土层厚度为10～30 cm的土柱;淋滤试验过程中在砂黏土层界面形成水分滞留层,界面处黏土层中NO_3~--N和NO_2~--N累积量均达到峰值,且随着深度的增加,NO_3~--N和NO_2~--N累积量降低;黏土层厚度差不小于20 cm的土柱内NO_3~--N累积量差异显著(P0.05),而40 cm黏土层的土柱反硝化量[(0.15±0.05) g]显著高于黏土层厚度为10～30 cm的土柱(P0.05),说明当黏土层达到一定厚度时(如40 cm),对NO_3~--N的阻滞作用和反硝化作用具有显著影响,对防止NO_3~--N淋失进入地下水产生重要作用。该研究可为层状包气带土壤条件下农田施肥管理与地下水保护提供科学依据。     

江苏句容水库农业流域农田土壤反硝化作用的研究

2008年6月、8月、12月和2009年3月,在江苏句容水库农业流域采集农田原状土壤样品,使用乙炔抑制实验室培养法测定土壤的反硝化速率,同时测定土壤的含水率、铵态氮（NH2-N）和硝态氮（NO_3-N）的含量,研究农田土壤反硝化速率变化、影响因素及其对流域氮损失的贡献。结果显示,旱地土壤反硝化速率范围在0．13-51．96kgN·hm^-2a^-1之间,水田土壤的反硝化速率范围在3．16-12．29kgN·hm^-2a^-1之间。相关分析表明,反硝化速率与土壤硝态氮（NO_3-N）浓度、铵态氮（NH2-N）浓度之间不具有显著相关关系;在12月和3月,反硝化速率与土壤含水率之间有显著相关关系,其他月份无显著相关关系。流域内农田土壤反硝化损失的总氮量为31．93tN·a^-1低于流域施氮总量的3．19％,可见,反硝化作用不是该流域氮损失的主要途径。     

华北平原不同农田类型土壤硝态氮累积及其对地下水的影响

针对华北平原典型农田的传统灌溉施肥带来的肥料浪费和环境污染问题,采集定州保护地蔬菜、小麦-玉米轮作农田土样及相应的地下水样品,研究了不同农田利用类型、保护地蔬菜不同种植年限和不同种植类型的土壤硝态氮的累积及对地下水污染的程度。结果表明,土壤剖面0-400cm范围保护地蔬菜的硝态氮累积量明显高于农田,0-100cm,100-200cm,200-300cm,300-400cm平均为815.0,293.6,394.9,313.4kg/hm2,分别为农田的12.3,3.8,4.6,5.1倍。保护地土壤剖面硝态氮累积量随着棚龄的增加而增加,尤其在0-60cm表现明显,0-100cm和100-200cm老龄棚(12a)土壤硝态氮累积量分别为815.0,293.6kg/hm2,高于低龄棚(8a)216.2,11.4kg/hm2。大棚黄瓜的土壤剖面硝态氮累积大于番茄,在根区外深层剖面出现多个明显的累积峰。保护地灌溉水、小麦-玉米轮作农田灌溉水及手压井饮用水NO3-N含量分别为9.6,7.4,10.5mg/L,超标率(10mg/L)分别为38%,16%,46%,该区域浅层饮用地下水已受到硝酸盐污染。     

华北平原农田厚包气带及含水层反硝化细菌的分离鉴定及作用机制研究

华北平原农田由于长期过量施用氮肥,造成了土壤硝酸盐累积,导致地下水硝酸盐污染日趋严重。微生物的反硝化作用可将土壤中累积的硝酸盐或亚硝酸盐还原为气态产物,是消减厚包气带土壤累积的硝酸盐的重要途径。因此筛选高效反硝化微生物资源,对人工强化厚包气带土壤反硝化脱氮,阻控地下水硝酸盐污染具有重要作用。基于此,本研究采集位于华北平原的中国科学院栾城农业生态系统试验站长期施氮[施氮量为600kg(N)·hm~(-2)·a~(-1)]定位试验0～150m农田厚包气带及含水层土壤样品,从中筛选到62株细菌。16SrRNA基因序列分析表明这62株菌株与变形菌门(Proteobacteria)、放线菌门(Actinobacteria)、厚壁菌门(Firmicutes)中的9个属具有较高的同源性。根据系统发育树的结果,挑选7株亲缘关系较远的菌株进行反硝化潜势试验,结果表明,菌株L71、L13和L103具备反硝化产气能力。电镜观察结果表明,这3株菌均为无鞭毛的杆状细菌,其长度分别为1.0μm、1.5μm和1.5μm,只有L103具有运动能力。此外,菌株L103具有完全反硝化能力,且脱氮能力受到pH的影响,在本试验条件下,菌株L103的反硝化速率高达1.62～2.36g(KNO_3)·d~(-1)·L~(-1),具备实际应用潜力。本研究表明华北平原厚包气带土壤中存在完全反硝化微生物,并可为人工强化治理厚包气带土壤硝酸盐污染提供菌种资源和理论依据。     

集约化种植条件下土壤硝态氮动态变化及累积特征研究

选取江阴市沿江平原地区的3种典型农业种植区,即大棚葡萄集约化种植基地、蔬菜集约化种植基地和常规种植农田为研究对象,通过田间现场采样分析的方法研究了不同种植方式下土壤剖面硝态氮含量的动态变化和累积特征.结果表明,葡萄种植基地0-100 cm各土层硝态氮含量随时间的变化波动较大,而蔬菜种植基地和常规种植农田的表层土壤硝态氮含量变化幅度大于深层土壤;3种典型种植区的土壤硝态氮含量均呈现随着土层深度的增加而逐渐减小的趋势,其中土壤硝态氮含量最大值出现在葡萄种植基地的20-40 cm土层中;葡萄种植基地各土层硝态氮平均累积量均高于蔬菜种植基地和常规种植农田,大棚葡萄集约化种植基地0-00 cm土层硝态氮平均累积总量高达400.96 kg/hm2,显著高于蔬菜集约化种植基地和常规种植农田的累积总量,这进一步表明不合理过量追肥导致土壤中硝态氮大量累积,增大了氮素淋失和地下水环境污染的风险.     

肥液浓度对不同形态氮素在土壤中运移转化特性的影响

为揭示肥液(尿素)浓度影响下土壤湿润体中不同形态氮素的运移转化规律,选取黏壤土和砂壤土作为肥液入渗试验供试土壤,量化分析肥液浓度对土壤累积入渗量和不同形态氮素在分布和再分布过程中运移转化特性的影响。结果表明:相同入渗时间内土壤累积入渗量随肥液浓度的增大而增加,Kostiakov公式的入渗系数与肥液浓度呈现线性关系,建立并验证了考虑肥液浓度影响的土壤累积入渗量估算公式,模拟值与实测值具有较高的一致性,两者间的相对误差绝对值均值均8.0%;入渗结束时,土壤湿润体相同位置处的尿素态氮、铵态氮(NH_4~+-N)和硝态氮(NO_3~--N)含量均随肥液浓度的增大而增加;NH_4~+-N主要分布在土壤湿润体深度20 cm以上,尿素态氮和NO_3~--N含量随着湿润体深度的增大呈现下降趋势;再分布过程中,土壤湿润体中尿素态氮含量随再分布时间的增加整体呈现减小趋势,且黏壤土和砂壤土湿润体中的尿素态氮分别在再分布5,3天时基本水解完成;NH_4~+-N含量呈现先增加后减小的趋势,黏壤土湿润体中的峰值约出现在再分布3～5天,而砂壤土约在再分布3天;黏壤土湿润体中NO_3~--N含量呈现先增加后减小的趋势,其峰值约在5～10天,而砂壤土中NO_3~--N含量在再分布10天时,始终保持在较高水平。研究结果为农田灌溉施肥系统的设计和管理提供理论基础和技术支撑。     

长期施肥下黄土旱塬黑垆土供氮能力的变化

【目的】本研究以36年长期定位试验为依托,分析了不同施肥处理对黄土旱塬区黑垆土全氮、碱解氮、微生物氮以及硝态氮和铵态氮的影响,以期为黄土旱塬区耕地质量的提高和农业可持续发展提供理论依据。【方法】田间试验始于1979年,设6个施肥处理,即不施肥(CK);单施氮肥(N);氮磷配合(NP);秸秆还田加氮磷肥(SNP);单施农家肥(M);农家肥加氮磷(MNP),试验基本为4年冬小麦-2年春玉米的一年一熟轮作制。于每年作物收获后以20 cm为间隔分层采集各处理0-100 cm土层土壤样品测定其土壤全氮、碱解氮、微生物氮以及硝态氮和铵态氮含量。【结果】长期施用有机肥能够明显提高旱塬区农田耕层土壤氮的总贮量,M和MNP处理的耕层土壤全氮含量较试验开始时提高了34.0%和42.7%;长期施有机肥能提高土壤中氮素养分的供应能力,SNP、M和MNP处理耕层土壤碱解氮含量比CK分别提高27.1%、34.2%和65.0%,比N处理提高了28.5%、35.7%和66.8%,比NP提高19.8%、26.5%和55.5%;长期施有机肥能够显著增加土壤有效氮的活性库,SNP、M和MNP处理的耕层土壤微生物氮比CK分别提高了217.0%、147.6%、120.2%;SNP、M和MNP处理能够有效减少土壤剖面中硝酸盐淋溶和深层累积,长期不施肥和单施化肥0-20 cm耕层NO_3~--N含量显著减少,相对MNP减少了58.3%~61.7%,长期单施氮肥土壤剖面深层硝态氮累积量最大在80-100 cm处硝态氮量达到23.98 kg/hm2,是NP处理的近7倍、MNP处理的51倍,长期施用有机肥和秸秆还田大幅度提高了0-20 cm耕层土壤硝态氮含量,降低了NO_3~--N向深层的转移,80-100 cm土层NO_3~--N含量不足0.5 mg/kg;长期单施氮肥0-100 cm剖面各层NO_4~--N含量均高于其它处理。【结论】长期施用农家肥、农家肥与氮磷肥配施、秸秆还田与氮磷肥配施既能增加旱地农田耕层土壤氮库,又能提高土壤中氮素养分的有效性和供应能力、扩大土壤有效氮的活性库,同时又可减少NO_3~--N向土壤深层的淋移和累积,使土壤中更多的NO_3~--N保留在耕层,耕层土壤矿质氮的蓄保能力增强,提高肥料利用率高,是黄土旱塬耕地质量提高和农业可持续发展的科学施肥方式。     

不同肥力潮土硝化潜势及其影响因素

依托河南郑州潮土长期定位施肥试验,探索不同肥力土壤的硝化潜势(NP)及其主要影响因素。采集高肥力土壤(有机无机肥配施)、中肥力土壤(化肥平衡施用)和低肥力土壤(不施肥或不施氮肥),分析土壤NP、全氮(TN)、铵态氮(NH_4~+-N)、硝态氮(NO_3~--N)、微生物生物量碳(MBC)和微生物生物量氮(MBN),并通过逐步回归、路径分析和方差分解分析(VDA)等统计分析方法,明确不同肥力潮土NP的主要影响因素,量化各主效应因子对NP的贡献率。结果表明:潮土NP为0.3～1.1 mg·kg~(-1)·h~(-1),在不同肥力梯度土壤中差异显著(P0.05),其中高肥力较中肥力平均提高7.9%;中肥力较低肥力平均提高162.5%。在各项土壤指标中,MBC、NO_3~--N、TN、MBN是土壤NP变化的主要影响因素,其中,MBC、NO_3~--N和MBN与NP为直接效应,TN与NP为间接效应大于直接效应,微生物生物量碳、氮(MBC和MBN)、NO_3~--N和TN对NP变异的贡献率分别为24.3%、18.9%和13.7%,而4个主效应因子交互作用对硝化潜势变异的贡献率达52.8%,各变量及其交互作用对硝化潜势变异的总贡献率达92.9%。可见,高肥力土壤上硝化作用较强,铵态氮很容易被硝化成为硝态氮,硝态氮累积和淋洗的可能性较大,应通过改善水肥条件适当降低其土壤硝化强度,进而达到构建氮素养分库和减少氮素损失的目的。     

应用Geoprobe对河北栾城土壤硝态氮含量进行计算

利用Geoprobe对土壤剖面取样,分析并计算了0~20.4m土层硝态氮的累积量,研究表明,施肥量的上升和地下水埋深的下降,使得多余的氮肥以硝态氮的形式存储在土壤剖面中,在传统的施肥制度下,0~20.4m剖面总累积的硝态氮量为1769kg hm-2,自地表至下,土壤硝态氮的分布存在三个累积层,分别为0~5.4m,7.2~12m,14.7~18.4m;而且三个层次累积的硝态氮量随深度呈递减的趋势。     

Absorption and transport of Na and Cl in rice cultivars differing in their tolerance to salinity: An examination of the effects of ammonium and potassium salts

The absorption and transport of Na and Cl from 0.1 mM and 10 mM ²²Na labelled NaCl or ³⁶Cl labelled KCl were examined in 15 days old seedlings of 3 cultivars of rice differing in their tolerance to salinity. Furthermore, the effects of 10, 100 and 1000 ppm (N)₂S on their uptake were studied. It was found that in general, the salt‐tolerant cultivars BR and PNL‐1 absorbed more Na and translocated a lesser proportion of it to the shoot, compared to the salt‐sensitive IR‐8, from 0.1 mM NaCl. The presence of (N)₂S reduced the uptake of Na in all the cultivars. It was also found that the presence of 100 ppm K, KN or NNreduced Na absorption from 0.1 mM NaCl significantly in all the cultivars, and the translocation to shoot in BR‐ Chloride transport from 0.1 mM NaCl was reduced by (N)₂S in all the cultivars. The 3 cultivars differed significantly in the rates of absorption and transport of Na and Cl. The results indicate that PNL‐1 which is a cross of IR‐8 X BR, has inherited the salt tolerance trait from BR. Lower rates of Na translocation to the shoot can be used as an index of salt tolerance in rice.     

An examination of the total analysis of major elements in soil samples

Recently conventional chemical analyses were mostly replaced by instrumental analysis. Although results from both methods were examined in details after the samples had been solubilized or extracted by appropriate techniques, the solubilization method was considerably altered so as to be convenient for the following analysis. In atomic absorption spectrophotometry (AAS), for example, fusion technique was mostly inadequate because of the higher salts concentration in the obtained solution. The use of H₂SO₄ must also be avoided in acid digestion for SO₄ ^2- precipitates with Sr²⁺ or La³⁺ which must be added to eliminate interferences in the succeeding procedure. Therefore, it is essential to consider the whole scheme including sample treatments to evaluate the suitability of instrumental analysis. In this experiment, the suitability of the methods which have been employed in our laboratory was examined by analyzing 9 rock standards.     

我国酸性硫酸盐土壤中铁锰形态转化及迁移

酸性硫酸盐土壤酸性很强，有机质含量高，造成了这种土壤所特有的铁锰淋洗、转化和迁移规律。研究结果表明：在酸性硫酸盐土壤中全铁含量较低，一般在３５－５０ｇ／ｋｇ（以Ｆｅ２Ｏ３计），全锰含量也低，一般在０．２５－０．５５ｇ／ｋｇ（以ＭｎＯ计），一般滩涂中全铁大于６０ｇ／ｋｇ，全锰大于１ｇ／ｋｇ。酸性硫酸盐土壤中，铁的游离度较小，一般在３７－７０％，铁的活化度较大，一般在８－２０％，而滩涂中铁的游离度一般     

Availability and extractability of soil manganese in a liming experiment

Abstract

The availability of soil Mn to corn in relation to extractability of soil Mn by EDTA, Mg(NO₃)₂, CH₃COONH₄, hydroquinone, H₃PO₄, and NH₄H₂PO₄ as affected by liming was evaluated under field conditions on a single soil type. EDTA, Mg(NO₃)₂ and CH₃COONH₄‐extractable Mn were related inversely to available Mn. No useful relationships were found between hydroquinone, H₃PO₄, and NH₄H₂PO₄‐extractable soil Mn and Mn uptake by sweet corn.     

Denitrification potential in a grassland subsoil: effect of carbon substrates

We examined the potential of a subsoil to denitrify nitrate under optimal anaerobic conditions in a laboratory-based incubation when supplied with a range of C substrates of increasing recalcitrance. Both topsoil and its associated subsoil were supplied with nitrate and either glucose, starch or cellulose. Microbial respiration and the evolution of N₂O and N₂ were measured. The subsoil supported low amounts of microbial activity and responded only to the glucose treatment; with less than one-fifth of the N₂O production measured in the top soil. Overall, our findings demonstrated that the denitrification potential of this particular subsoil is relatively low and that only simple carbohydrates could be utilised readily by the resident microorganisms.     

CO2, CH4 and N2O fluxes of upland black spruce (Picea mariana) forest soils after forest fires of different intensity in interior Alaska

Abstract

Forest fires can change the greenhouse gase (GHG) flux of borea forest soils. We measured carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N₂O) fluxes with different burn histories in black spruce (Picea mariana) stands in interior Alaska. The control forest (CF) burned in 1920; partially burned (PB) in 1999; and severely burned (SB1 and SB2) in 2004. The thickness of the organic layer was 22 ± 6 cm at CF, 28 ± 10 cm at PB, 12 ± 6 cm at SB1 and 4 ± 2 cm at SB2. The mean soil temperature during CO₂ flux measurement was 8.9 ± 3.1, 6.4 ± 2.1, 5.9 ± 3.4 and 5.0 ± 2.4°C at SB2, SB1, PB and CF, respectively, and differed significantly among the sites (P < 0.01). The mean CO₂ flux was highest at PB (128 ± 85 mg CO₂-C m^?2 h^?1) and lowest at SB1 (47 ± 19 mg CO₂-C m^?2 h^?1) (P < 0.01), and within each site it was positively correlated with soil temperature (P < 0.01). The CO₂ flux at SB2 was lower than that at CF when the soil temperature was high. We attributed the low CO₂ flux at SB1 and SB2 to low root respiration and organic matter decomposition rates due to the 2004 fire. The CH₄ uptake rate was highest at SB1 [–91 ± 21 μg CH₄-C m^?2 h^?1] (P < 0.01) and positively correlated with soil temperature (P < 0.01) but not soil moisture. The CH₄ uptake rate increased with increasing soil temperature because methanotroph activity increased. The N₂O flux was highest [3.6 ± 4.7 μg N₂O-N m^?2 h^?1] at PB (P < 0.01). Our findings suggest that the soil temperature and moisture are important factors of GHG dynamics in forest soils with different fire history.     

碳酸氧镧改性生物炭材料的合成及对磷酸盐去除性能

为高效去除废水中过量的磷酸盐为目的，该研究将研究利用艾草生物质与镧溶液共生共热的方法制成具有大量纳米级碳酸氧镧突起的镧基复合生物炭材料，研究了材料投加量、初始磷酸盐浓度、吸附时间、初始溶液pH值和共存离子对其吸附磷酸盐性能的影响及饱和磷吸附镧基复合生物炭材料（La-CB2-P）对生菜种子发芽率的试验。试验结果表明：La-CB2最佳投加量为1 g/L，最佳吸附温度为25 ℃，对磷酸盐的吸附主要为多分子层吸附，Langmuir模型模拟最大吸附容量为126.82 mg/g，并在12h内达到吸附平衡，酸性至中性水环境中La-CB2吸附性能更优，并对碱性水环境的pH值具有缓冲作用，在pH值为3时La³⁺浸出率为7.66%，其他pH值条件下仅为0.029%左右，在磷吸附过程中La-CB2的DOC溶出量随着初始溶液pH值的升高呈先增后减的趋势，在多种共存阴离子中对磷酸盐具有很强的选择性吸附，水体中的腐殖酸会大幅度降低La-CB2对磷酸盐的吸附性能。饱和磷吸附镧基复合生物炭材料（La-CB2-P）能够作为磷缓释肥显著促进生菜发芽，对La-CB2在富营养水体的磷吸附及资源回收提供了大量的理论基础。     

Acidifying emissions in The Netherlands

The emission of acidifying compounds to air in the Netherlands, expressed as acidifying equivalents, consisted in 1992 mainly of NO_X (45%), NH₃ (35%) and SO₂ (20%). Transportation, agriculture and large combustion plants each contributed about 30% to the national total emission of acidifying compounds. The emissions from transportation activities mainly consisted of NO_X, while in agriculture NH₃ emission strongly dominated. Combustion processes in large combustion plants resulted both in SO₂ emissions (especially from refineries) and NO_X emissions (especially from public power plants). The total emission of acidifying substances decreases steadily in the Netherlands. The emission in 1992 was 24% lower than in 1985. It is expected to decrease further in future. The emission levels in 1992 and 1993 still are more than twice as high as the emission objective for the year 2000, set by Dutch environmental policy.     

Sulfur dioxide inhibition of photosynthesis at different CO2 and O2 concentrations in relation to photorespiration

The mechanism of SO₂ inhibition of photosynthesis in intact leaves of tomato and maze was studied to evaluate SO₂ inhibition of photorespiration. Leaf tissues were fumigated with SO₂ under photorespiratory (low CO, and/or high O, concentrations) and non-photo-respiratory conditions. When tomato leaf disks were fumigated with 10 ppm SO₂ at 2, 21 and 100° o O., SO₂ inhibited photosynthesis at 2% O₂ in the same degrees as at 21% O₂. SO₂ inhibition of photosynthesis was depressed at higher CO₂ concentrations when the disks were fumigated with SO₂ at different CO₂ concentrations. High CO₂ concentrations also reduced the photosynthesis inhibition of maize leaf disks. These results suggest that SO₂ inhibits photosynthesis through other mechanisms than photorespiration inhibition and confirm the view that SO₂ competes with CO₂ for the carboxylating enzymes in photosynthesis     

Effects of NaHCO3 on photosynthetic characteristics,and iron and sodium transfer in pomegranate

In order to study effects of sodium bicarbonate (NaHCO₃) stress in irrigation water on photosynthetic characteristics and iron (Fe) and sodium (Na⁺) translocation content of pomegranate plants, a factorial experiment was conducted based on completely randomized design with three cultivars of pomegranate (“Gorch-e-Dadashi,” “Zagh-e-Yazdi,” and “Ghermez-e-Aliaghai”) and four concentrations of NaHCO₃ (0, 5, 10, and 15 mM), with three replications. The results of plant analysis indicated that NaHCO₃ affected chlorophyll index, F_v/F_m, and performance index (PI) in upper and lower leaves of shoots and also the translocation of Na⁺ and Fe. The results also showed that Fe translocation from root to shoot reduced at 15 mM level of NaHCO₃. The highest Na translocation and the lowest Fe translocation were observed in Zagh-e-Yazdi and Ghermez-e-Aliaghai cultivars, respectively. The ratio of sodium/potassium (Na⁺/K⁺) in stems was higher than that in roots and leaves, and the observed chlorophyll content of upper leaves was also lower than that of lower leaves. Based on the measured parameters Gorch-e-Dadashi cultivar showed less relative sensitivity than other cultivars to NaHCO₃ of irrigation water through maintaining the lower Na⁺ transport to the shoots, and improvement of Fe transport to shoots.