Inductively coupled plasma optical emission spectrometric determination of minerals in thyme honeys and their contribution to geographical discrimination

Twenty-four Spanish thyme honey samples were analyzed using inductively coupled plasma optical emission spectrometry (ICP-OES). Twenty-four minerals were quantified for each honey. The elements Al, As, Ba, Ca, Cr, Cu, Fe, K, Li, Mg, Mn, Na, P, Pb, S, Se, Si, Sr, and Zn were detected in all samples; seven elements are very abundant (Ca, K, Mg, Na, P, S, and Si), and six are not abundant (Al, Cu, Fe, Li, Mn, and Zn). Eleven of them are trace elements (As, Ba, Cd, Co, Cr, Ni, Mo, Pb, Se, Sr, and V) at <1 mg kg(-)(1). Classification of thyme honeys according to their origin (coast, mountains) was achieved by pattern recognition techniques on the mineral data. By means of principal component analysis, a good separation by geographical origin is obtained when scores for the two first principal components are plotted. Classification functions of 11 metals (Al, As, Cr, Cu, K, Li, Mg, Na, P, S, and V) were obtained using stepwise discriminant analysis and applied to classify correctly approximately 100% of the honey samples.     

钙对NaCl胁迫下马铃薯脱毒苗离子吸收、分布的影响

【目的】马铃薯是对盐分较敏感的农作物,土壤盐渍化会严重影响马铃薯的生长发育及其产量和品质。有关钙对Na Cl胁迫下马铃薯离子吸收、分布的研究较少。本文通过研究不同浓度Ca Cl2对Na Cl胁迫下马铃薯脱毒苗离子吸收、分布和运输的影响,探讨钙对Na Cl胁迫下马铃薯的调控机制,为盐渍土上马铃薯的生产提供理论依据与技术支持。【方法】以‘克新一号’马铃薯品种为试验材料,采用组织培养方法,将0、5、10、15和20 mmol/L Ca Cl2与0、25、50和75 mmol/L Na Cl分别添加到MS+2mg/L B9+3%蔗糖+0.9%琼脂培养基中,制成不同处理组合的培养基。将继代培养的脱毒苗按单节茎段剪切接种到培养基中进行培养。接种30天时调查脱毒苗生物量和Na+、Cl-、K+、Ca2+、Mg2+、P积累量,并分析Na+/K+、Na+/Ca2+、Na+/Mg2+比值及根系与茎叶的SK、Na、SMg、Na和SCa、Na值,探讨离子吸收、运输及分布情况。【结果】Na Cl胁迫抑制马铃薯脱毒苗的生长,随Na Cl胁迫浓度的增加,马铃薯脱毒苗鲜重、干重显著下降,各器官Na+和Cl-含量极显著增加,K+含量显著下降,Ca2+和Mg2+含量减少,茎、叶中P含量降低而根中P含量增加。Na+/K+、Na+/Ca2+、Na+/Mg2+比值随Na Cl胁迫浓度的增加而升高。随Na Cl胁迫浓度的增加,马铃薯脱毒苗根系与茎叶的SK、Na和SMg、Na值逐渐降低,SCa、Na值呈先升高后降低趋势。0、25和50 mmol/L Na Cl胁迫浓度下,以10 mmol/L Ca Cl2处理的马铃薯脱毒苗根、茎叶鲜重和干重最高,75 mmol/L Na Cl胁迫下以15 mmol/L Ca Cl2处理的马铃薯脱毒苗生物量最高。各Na Cl胁迫浓度下,添加Ca Cl2后,马铃薯脱毒苗各器官Na+含量明显降低,Cl-含量显著增加,K+、Ca2+、Mg2+含量升高,P含量先降低后升高。0、25、50和75 mmol/L Na Cl胁迫浓度下,添加适量Ca Cl2可明显降低马铃薯脱毒苗各器官Na+/K+、Na+/Ca2+、Na+/Mg2+比值,提高SK、Na、SMg、Na和SCa、Na值,增强K+、Ca2+、Mg2+向地上部的选择运输能力,抑制Na+向地上部的选择运输能力,维持细胞内离子平衡,缓解盐胁迫造成的营养亏缺。【结论】Na Cl胁迫下添加外源钙,能够有效改善马铃薯脱毒苗体内的离子平衡,促进营养吸收,Na+向叶片选择运输能力降低,K+、Ca2+、Mg2+向地上部的选择运输能力增强,离子在各器官水平上的区域化分布发生改变是钙缓解盐胁迫的重要生理机制之一。     

磷钾肥施用对日光温室土壤溶液离子组成的影响

采用土培模拟试验研究了施用磷、钾肥对大田和温室土壤溶液电导率（EC）、离子含量及其比例的影响。结果表明,温室栽培土壤溶液EC、K+、Na+、Ca2+、Mg2+、NO3-含量以及K+ / Ca2+、K+ / Mg2+摩尔比分别为大田土壤的2.5、95.0、16.6、1.9、3.2、4.0、31.0和39.0倍,说明日光温室土壤离子累积及养分比例失调问题突出。施用磷、钾肥对土壤溶液中不同离子含量的影响不同,增加磷肥施用量,显著降低了大田和温室土壤溶液EC和Ca2+、Mg2+离子含量,而对土壤溶液K+、NO3--N和NH4+-N离子浓度均无显著影响;随施钾量增加,大田及温室土壤溶液EC、K+、Na+、Ca2+、Mg2+和K+/Ca2+、K+/Mg2+摩尔比均呈显著增加趋势。温室栽培实践中因过量施用磷、钾肥而造成的阳离子养分比例失调而带来的营养及生态环境问题值得关注。     

脱硫石膏与灌溉耦合对滨海盐碱土化学性质的影响

脱硫石膏(CaSO4.2H2O)是火力发电厂石膏湿法烟气脱硫的副产物。对盐碱地施用脱硫石膏可以通过Ca2+置换盐土中的Na+,达到脱盐目的。通过盆栽试验研究天津滨海盐土施用脱硫石膏并配合灌溉淋洗改良盐碱土的效果。结果表明:对于表层土壤(0-10cm),施用脱硫石膏对Ca2+、Mg2+、K+、Na+、Cl-、SO24-离子含量有显著降低作用。10cm以下土壤,脱硫石膏的脱盐能力与施用量呈正相关。脱硫石膏与灌溉耦合时,脱硫石膏施用量为3 000kg/hm2以上时改良效果较好。随着脱硫石膏施用量的增加不但降低了土壤Na+含量与土壤pH值,对灌溉量的需求也有所降低。灌溉量为田间持水量的80%时脱硫石膏对土壤Ca2+、Mg2+与K+的降低作用与CK相比差异最显著。脱硫石膏施用量的增加提高了土壤全盐量,但随灌溉量增加这种影响逐渐降低。     

基于电导率和结构稳定性阳离子比的微咸水灌溉水质评估方法

电导率（Electrical Conductivity,EC）和结构稳定性阳离子比（Cation Ratio of Soil Structural Stability,CROSS）是评估微咸水对土壤渗透性能影响的重要指标。虽然CROSS全面地考虑了Na+、K+、Ca2+和Mg2+对土壤结构稳定性的复杂影响,但CROSS的离子浓度系数在不同地区的适用性存在差异,有必要根据当地的水质条件确定基于EC和CROSS评估方法的分类标准。该研究旨在分析CROSS替代钠吸附比（Sodium Adsorption Ratio,SAR）评估水质危害的合理性以及其在河套灌区的适用性。在河套灌区不同区域采集73份地下水水样,并采用EC和SAR、EC和CROSS对其进行评估。结果表明,基于2种方法的地下水分类结果中,仅有34.25%的水样分类结果相同,并且不同的CROSS计算方法（基于阳离子相对絮凝能力（Flocculation）的CROSSf、相对分散能力（Dispersion）的CROSSd和优化的（Optimal）CROSSopt）在河套灌区的适用性也不相同。建议采用CROSSd或CROSSopt,并结合土壤盐分和离子浓度评估河套灌区地下水水质。该评估方法更全面地考虑了地下水和土壤中的离子组成对土壤渗透性能的影响,有效避免了不合理的微咸水利用导致的土壤结构恶化等问题,可为微咸水的安全可持续利用提供理论支撑。     

重庆缙云山酸沉降背景下针阔混交林水化学特征初步研究

选取三峡库区缙云山小流域针阔混交林作为研究对象,对其大气降水、穿透雨、树干茎流、地表径流等水文过程中的pH值及Na+、K+、Ca2+、Mg2+等离子含量进行研究,结果表明:(1)大气降水pH值为5.31,呈酸性,已属于酸雨范围(pH<5.65)。相对于大气降水,针阔混交林穿透雨和树干茎流离子含量均大幅增加。穿透雨和树干茎流中,Mg、Cu元素的变异系数均小于大气降水,而K、Zn和Mn均大于大气降水。地表径流中Ca元素含量最高,为16.416mg/L,Mn元素含量最低,几乎检测不到。各元素含量排序为:Ca>K>Na>Mg>Zn>Fe>Cu>Mn。地下径流中,Ca元素是含量增加最多的养分元素,各元素含量排序为:Ca>K>Na>Mg>Zn>Cu>Fe=Mn。(2)Cu元素在穿透雨和树干茎流中均出现了负淋溶,其余各元素浓度均有所增加。如果林木长期处于酸雨逆境下,将会导致部分营养元素大量流失,并最终造成林木营养亏损且影响其生长。     

NaCl胁迫下中国南瓜杂交种和黑籽南瓜植株离子吸收与积累特性研究

营养液栽培条件下,在成株期以 80 mmol/L NaCl 胁迫中国南瓜 360-3×112-2 F1和黑籽南瓜植株,10d 后,测定了植株的生长量和不同器官中Na+、K+、Ca2+、Mg2+的含量。结果表明,NaCl 胁迫下两种材料的生长受到明显抑制,360-3×112-2杂交种的生长抑制比黑籽南瓜植株较轻。NaCl 胁迫后两种南瓜植株体内Na+含量升高,360-3×112-2杂交种的Na+主要累积在根部,黑籽南瓜主要积累在茎中;K+、Ca2+、Mg2+的含量在植株体内呈下降的趋势,但360-3×112-2杂交种的上位叶中的含量却上升。NaCl胁迫下,因Na+的积累抑制了K+的吸收,植株各器官的K+/Na+普遍降低,但黑籽南瓜比360-3×112-2杂交种的K+/Na+下降明显。这些结果说明,两种南瓜受到盐胁迫后Na+的主要积累器官不同,致使地上部各器官有不同的K+、Ca2+、Mg2+吸收和积累特性,K+/Na+降低幅度也不同,从而影响了植株的生长,产生了耐盐性的差异。360-3×112-2杂交种耐盐性比黑籽南瓜强,可望作为耐盐砧木在瓜类生产上使用。     

盐胁迫对小型西瓜幼苗体内离子分布的影响

采用营养液水培法,研究了不同NaCl浓度对耐盐性不同的两个小型西瓜品种（秀雅和秀丽）幼苗体内离子分布的影响。结果表明,NaCl胁迫抑制了西瓜幼苗的生长,秀雅生长受抑制程度明显小于秀丽; 随NaCl浓度的提高,植株体内Na+和Cl－含量增加,K+、 Ca2+和Mg2+含量降低。5种离子在器官间呈区域化分布,Cl－主要积累在茎中而Na+主要积累于茎和根中; K+含量在茎中降低幅度较大,叶中降低幅度较小; Ca2+和Mg2+主要存在于茎和叶中,且在叶中降低幅度较小。NaCl胁迫下,西瓜根向茎选择性运输K+和Ca2+的能力降低,而茎向叶选择性运输的能力提高,有利于减轻NaCl胁迫对叶片的伤害。与秀丽相比,秀雅叶中K+、 Ca2+含量降低幅度较小,Cl－和Na+积累量较少,K+/Na+和Ca2+/Na+比值均较高,茎向叶运输的SK,Na和SCa,Na值也较高。以上结果说明,向叶片运输Na+的选择性较低,是秀雅耐盐性较强的主要原因之一,离子在器官水平上的区域化分布是西瓜植株适应盐胁迫的重要生理机制之一。     

第四纪红色粘土发育的红壤中营养元素的淋失

A red soil derived from Quaternary red clay was employed to study nutrient leaching with soil columns repacked in laboratory. The objective was to identify the effects of fertilization practices on leaching patterns and magnitudes of Ca²⁺, Mg²⁺, K⁺, NH₄⁺, and NO₃^-. The treatments were CK (as a control), CaCO₃, CaSO₄, MgCO₃, Ca(H₂PO₄)₂, urea, KCl, and multiple (a mixture of the above-mentioned fertilizers). 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 peristaltic pumps over a period of 92 days. Leaching processes of NH₄⁺, and NO₃^- were only measured in CK, urea, and multiple treatments which were directly related to N leaching. Results showed that sole application of CaSO₄, and Ca(H₂PO₄)₂ scarcely had any effect on the leaching losses of Ca²⁺, Mg²⁺, and K⁺; the application of MgCO₃ stimulated the leaching of Mg²⁺; the application of CaCO₃ promoted the leaching of Ca²⁺, Mg²⁺ and K⁺; urea treatment also promoted the leaching of K⁺ and NH₄⁺, and NO₃^- leaching mainly occurred at late stage of leaching process in particular; under KCl treatment, leaching of Ca²⁺, Mg²⁺, and K⁺ was promoted to a large extent; under multiple treatment, leaching of Ca²⁺, Mg²⁺, K⁺, NH₄⁺, and NO₃^- was all increased and NO₃^- was mainly leached at the end of leaching process and still had a trend of increase.     

Chemical Composition of Urban Wet Deposition in Amman,Jordan

Precipitation events were collected during the period from October 1996 to April 1997 from two sites in the city of Amman, Jordan. The samples were analyzed for major cations (Na+, K+, Ca2+, Mg2+ and NH4+), major anions (F-, Cl-, NO3- and SO42-), in addition to heavy metals (Cu2+, Cd2+, Zn2+, and Pb2+). High levels of Ca2+ and SO42- were observed. The results were comparable with some regional values and they indicate that about 58% of Na+ and Cl- are of marine origin, while Ca2+, K+ and a large fraction of SO42- are of soil dust origin. Heavy metals were detectable in most of the samples, zinc showed the highest concentrations. Significant correlation was obtained between zinc and lead, which may indicate automobile emission source.     

A Study on Chemical Composition of Atmospheric Precipitation at Savar,Joydevpur, Tongi and Narayanganj,Bangladesh

Precipitation was collected on an event basis from July 1994 to August 1995 at towns around the capital Dhaka of Bangladesh. The major chemical components were determined by atomic absorption spectrophotometry, UV-Visible spectrophotometry and ion selective electrode method. The concentrations of nitrate and sulphate were found to be below the minimum detection limit of 1.0 mg L- 1; the concentrations of Cl-, Na+, K+, Ca+2, Mg+2 and NH4+ ranged from <1.0–3.03, 0.14–1.70, 0.04–0.37, 0.04–1.30, <0.02–0.20 and <0.10–2.33 mg L-1, respectively. The values of pH and conductivity ranged from 4.80–6.74 and 3.3–37.5 μS cm-1, respectively.     

氮肥施用对砖红壤硝态氮和盐基离子淋失特征的影响

氮肥品种的合理选用对作物增产增收、 土壤酸化改良有重要的影响。本文以海南省海口市观澜湖采集的砖红壤为研究对象,采用室内土柱模拟试验,对尿素、 硝酸铵和硫酸铵3种氮肥处理下砖红壤硝态氮及盐基离子（Ca2+、 Mg2+、 K+、 Na+）淋失特征进行了研究。结果表明, 1）硝态氮累积淋溶量表现为硫酸铵硝酸铵尿素N0,且硝态氮的淋溶量与施肥量呈正相关关系,整个淋溶过程中硝态氮累积淋溶量（y kg/hm2）与施肥量（x kg/hm2）之间满足线性方程 y=3.3064x+315.74（R2=0.8848）; 2）尿素、 硝酸铵、 硫酸铵处理整个淋溶过程的盐基离子淋溶量均表现为 Ca2+Mg2+K+Na+,且盐基离子淋溶总量（kg/hm2）表现为硫酸铵（1821.12）硝酸铵（1080.27）尿素（872.24）N0（417.23）; 3）砖红壤盐基离子迁移速率表现为硫酸铵（26.28%）硝酸铵（13.37%）尿素（11.78%）,尿素、 硝酸铵和硫酸铵处理分别以线性方程 y=0.1178x+123.18（R2=0.9121）、 乘幂方程 y=15.634x0.4423（R2=0.9259）和对数方程 y=128.38e0.0007x（R2= 0.9244）的拟合度最高。     

Inductively coupled plasma emission spectroscopic determination of nine elements in infant formula: collaborative study

Results from a collaborative study of a method for the determination of 9 elements in infant formula, using inductively coupled plasma emission spectroscopy, are reported. Six collaborators analyzed 6 infant formulas for native and spiked levels of Ca, Cu, Fe, Mg, Mn, P, K, Na, and Zn. The within-laboratory and between-laboratory coefficients of variation were generally (69 of 108 samples) below 9% for all elements determined in all samples. Most of the average recoveries of the elements from spiked samples ranged from 90 to 105%. The method has been adopted official first action for determining Ca, Cu, Fe, Mg, Mn, P, K, Na, and Zn in infant formula.     

外源 GSH 对 NaCl 胁迫下番茄幼苗叶片及根系离子微域分布的影响

【目的】盐胁迫是限制新疆番茄生长的重要障碍因子之一,而外源喷施谷胱甘肽 (GSH) 是解决这一问题的有效措施。探讨外源 GSH 缓解番茄盐胁迫的效应和作用机制,可为该措施的有效应用提供理论依据。 【方法】采用营养液栽培法,选用番茄品种‘中蔬四号’为试材。在营养液中加入 NaCl 100 mg/L,使其产生盐胁迫,以不加 NaCl 作为对照 (CK),试验处理包括不喷施 GSH (NaCl)、喷施 GSH (+ GSH)、喷施 GSH 合成酶抑制剂 (+ BSO) 以及喷施 GSH 和 BSO (+ BSO + GSH)。测定番茄幼苗叶片和根系中与耐盐性相关的 K+、Ca2+、Mg2+、Na+ 和 Cl– 的离子微域分布状态和平衡。 【结果】NaCl 胁迫下番茄叶片和根系所有组织细胞中 Na+ 和 Cl– 相对含量显著提高,K+ 相对含量和 K+/Na+、Ca2+/Na+、K+/Cl– 比值降低,说明 NaCl 胁迫使细胞中 Na+ 和 Cl– 有害离子积累及胞内离子稳态严重破坏;外源 BSO 施用进一步加剧了 NaCl 胁迫下番茄叶片和根系细胞的 K+/Na+ 失衡。而外源 GSH 施用抑制了 NaCl 胁迫下番茄叶片和根系对 Na+ 的吸收,降低了 Cl– 的相对含量,提高了 K+/Na+、Ca2+/Na+、K+/Cl– 比值。外源 GSH 亦使 NaCl+BSO 胁迫下番茄叶片各组织及根系中皮层、内皮层和中柱的 Na+ 未检出,根系和叶片各组织中 Cl– 相对含量显著降低,K+ 和 Ca2+ 相对含量及 K+/Na+、Ca2+/Na+、K+/Cl–、Ca2+/Cl– 比值显著提高。 【结论】外源 GSH 通过抑制盐胁迫下番茄叶片和根系对 Na+ 的吸收,降低 Cl– 吸收,改善细胞中离子的微域分布和维持离子平衡, 从而缓解了盐胁迫对番茄的毒害作用,提高了番茄的耐盐性。     

Searching the most appropriate sample pretreatment for the elemental analysis of wines by inductively coupled plasma-based techniques

Different sample preparation methods were evaluated for the simultaneous multielement analysis of wine samples by inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS). Microwave-assisted digestion in closed vessel, thermal digestion in open reactor, and direct sample dilution were considered for the determination of Li, Be, Na, Mg, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, Y, Mo, Cd, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Tl, Pb, and Bi in 12 samples of red wine from Valencia and Utiel-Requena protected designation of origin. ICP-MS allows the determination of 17 elements in most of the samples, and using ICP-OES, a maximum of 15 elements were determined. On comparing the sample pretreatment methodology, it can be concluded that the three assayed procedures provide comparable results for the concentration of Li, Na, Mg, Al, K, Ca, Mn, Fe, Zn, and Sr by ICP-OES. Furthermore, ICP-MS data found for Cu, Pb, and Ba were comparable. Digestion treatment provides comparable values using both total decomposition in open system and microwave-assisted treatment for Cu by ICP-OES and for Cr, Ni, and Zn by ICP-MS. Open vessel total digestion provides excess values for Cr, Mn, Fe, and Zn by ICP-OES and defect values for Se. However, direct measurement of diluted wine samples provided uncomparable results with the digestion treatment for Mn, Cu, Pb, Zn, Ba, and Bi by ICP-OES and for Mg, Cr, Fe, Ni, and Zn by ICP-MS. Therefore, it can be concluded that microwave-assisted digestion is the pretreatment procedure of choice for elemental analysis of wine by ICP-based techniques.     

Concentrations of Major and Minor Mineral Elements in Different Organs of Kosteletzkya virginica and Saline Soils

Abstract

Kosteletzkya virginica (L.) Presl. is a perennial dicot halophytic species that grows in brackish portions of coastal tidal marshes of the mid-Atlantic and southeastern United States. It was introduced into Northern Jiangsu, China, by the Halophyte Biotechnology Center (University of Delaware, Newark, DE) as a species with potential to improve the soil and develop ecologically sound saline agriculture. Fifteen major and minor elements [calcium (Ca), magnesium (Mg), phosphorus (P), sodium (Na), potassium (K), iron (Fe), manganese (Mn), zinc (Zn), lead (Pb), cadmium (Cd), aluminum (Al), copper (Cu), lithium (Li), cobalt (Co), and vanadium (V)] in roots, stems, leaves, and seeds of Kosteletzkya virginica and saline soils were measured in the study. Concentrations of Al, Fe, Zn, Mn, V, and Pb were the highest in soils, whereas concentrations of Na, Li, Cu, Ca, and Mg were the highest in the roots, stems, and leaves, respectively, and concentrations of K and P were the highest in the seeds. Potassium, P, Mg, and Ca were the main constituents in the seeds, and concentrations of Fe, Li, Mn, Zn, and Cu in seeds were relatively high. However, concentrations of Na and Al were very low in the seeds. The K/Na ratio in the seeds was 34.26, and the Ca/P ratio was 0.52, which was less than the maximum tolerable value for the human diet. These proportions were considered to be an advantage from a nutritional point of view. From roots to stems to leaves, increases in K/Na, Ca/Na, and Ca/Mg ratios could mitigate salt stress of the growth habitat of Kosteletzkya virginica. These results suggest that Kosteletzkya virginica is a halophytic species with potential as a rich source of mineral-element supply, and its products could be used for development of food, fodder, health care products and industrial raw materials.     

外源EBR对NaCl胁迫下紫花苜蓿幼苗微量元素 吸收及叶绿素荧光动力学参数的影响

为明确外源2,4-表油菜素内酯(2,4-epibrassinolide,EBR)诱导紫花苜蓿(Medicago sativa L.)幼苗抗盐性的效果及其可能的生理调节机制,采用营养液水培法,以紫花苜蓿品种‘中苜3号’和‘陇中苜蓿’为材料,研究Na Cl胁迫下施用外源EBR对紫花苜蓿幼苗微量元素吸收及叶片PSⅡ功能、电子传递速率和光能分配的影响。结果表明:150 mmol·L~(-1) Na Cl胁迫下,苜蓿幼苗不同器官(叶片、茎秆、根系)中的Cu~(2+)含量显著升高,Fe~(2+)、Mn~(2+)、Zn~(2+)含量和Fe~(2+)/Na+、Mn~(2+)/Na+、Cu~(2+)/Na+、Zn~(2+)/Na+显著降低,无机离子的吸收、运输和分配等代谢平衡被打破;同时Na Cl胁迫造成苜蓿幼苗叶片PSⅡ反应中心受损,天线耗散、反应中心耗散增加,光合能力下降。Na Cl胁迫下,施用0.1μmol·L~(-1)外源EBR后,苜蓿幼苗不同器官(叶片、茎秆、根系)中的Cu~(2+)含量显著降低,Fe~(2+)、Mn~(2+)、Zn~(2+)含量及Fe~(2+)/Na+、Mn~(2+)/Na+、Cu~(2+)/Na+、Zn~(2+)/Na+显著升高,幼苗体内无机离子的吸收、运输得到有效调控,Na+和Fe~(2+)、Mn~(2+)、Cu~(2+)、Zn~(2+)等阳离子间的拮抗作用减小;苜蓿幼苗叶片的F_0、NPQ显著降低,F_m、F_v/F_0、F_v/F_m、ФPSⅡ、F_v′/F_m′、q P和ETR显著升高,苜蓿幼苗叶片吸收的光能用于光化学反应部分(P)增加、天线色素耗散部分(D)和反应中心过剩光能部分(E)降低。说明外源EBR能够促进Na Cl胁迫下苜蓿幼苗对无机离子的选择性吸收、运输和分配,维持体内的离子代谢平衡,通过提高光合电子传递效率,降低天线热耗散和反应中心过剩光能,维持较高的PSⅡ光化学活性,进而平衡激发能在PSⅠ、PSⅡ之间的分配,降低Na Cl胁迫对PSⅡ反应中心的损伤程度,有效缓解Na Cl胁迫对苜蓿幼苗所造成的伤害。     

小麦秸秆热解过程中碳和微量元素迁移转化规律

为研究小麦秸秆热解过程中碳元素和微量元素的迁移转化规律,依托连续式作物秸秆分段均匀炭化联产系统,基于热解炭化生产工艺,测算及分析碳元素在秸秆热解过程中的存在形式及迁移转化量,利用HSC Chemistry软件模拟微量元素在秸秆热解炭化过程中的组分变化,分析了8种微量元素的迁移转化规律,为生物质热解机理的进一步研究提供支撑,为提高秸秆热解炭品质提供强有力保证。结果表明:经测试及测算得到的碳元素迁移足迹图符合碳元素质量守恒定律,碳元素迁移到热解炭中41.12%,以固定碳存在;22.83%迁移到焦油中,以大分子长链烃和环链烃存在;26.62%的碳元素以六碳内的短链烃存在于热解气;4.71%迁移到木醋液中为醛、酮、酸等。小麦秸秆中含量在100μg/L以上的8种高富集微量元素里,K、Na、Ca、Mg主要以硫酸盐、磷酸盐及氯化物形式存在于热解炭中,Al、Fe多以氧化物、硫化物以及硅、氧共融物形态被大量保留在热解炭中,而P、S元素在热解炭化过程中的析出主要是有机结合物的分解。     

The Transfer of Chemical Elements within a Heath-Ecosystem (Calluna vulgaris) in Northwest Germany

The purpose of this investigation was to describe the element budget of a heathland area in Northwest Germany by measuring the fluxes of elements within the ecosystem. The following fluxes were considered: input by precipitation, canopy-drip, mineralisation, ion uptake, litterfall, output with seepage water. The elements H, Na, K, Ca, Mg, Mn, Fe, Al, S, P, CI, NO, NH, N_org were analysed, the period of investigation was one year. The results demonstrate the high importance of deposited nutrients like N (especially No3), Ca and Mg for the element budget and the stability of a heath-ecosystem. The internal turnover of K, Ca, Mg and Mn within the ecosystem mainly took place by leaching. No leaching was found for N, P, AI, Fe, S, CI, Na. For these elements litterfall was the dominant internal way of cycling. The humus layer was a sink for total-N, NO, Ca, Mg, Mn, Fe and S. NO, Ca, Mg, Mn and S were removed from the percolating solution, while for Fe and especially N and Mn an inhibition of mineralisation was found. The element balance for the mineral soil showed that this part is a sink for Hand a source mainly for Al, Ca and Mg, less for K and Na. From the cation/anion balance of the storage changes in mineral soil the ecosystem-internal H ion production was calculated as 0.4 keq per ha and year. It may be traced back to an uptake of NH, and dissociation of fulvic acids in the mineral soil. The results are discussed with respect to the development, stability and management of heath-ecosystems.     

伊朗西部地区碱性土壤中共离子对Zn吸附的影响

Zinc(Zn) is essential to plant growth and relatively mobile in soils.This study was conducted to assess the effect of common ions(Ca 2+,K +,Na +,NH + 4,Cl,NO 3,and H 2 PO 4) on sorption of Zn in surface samples of ten calcareous soils from western Iran using 10 mmol L 1 KCl,KNO 3,KH 2 PO 4,Ca(NO 3) 2,NaNO 3,and NH 4 NO 3 solutions as background electrolytes.The results indicated that both NH + 4,K +,and Ca 2+ equally decreased Zn sorption as compared to Na +.Zinc sorption was decreased by H 2 PO 4 as compared to NO 3 and Cl.The Langmuir and Freundlich equations fitted closely to the sorption data of all ions.The Langmuir maximum,bonding energy constant,and Freundlich distribution coefficient for Zn sorption differed among the various ionic background electrolytes.Langmuir sorption parameters showed that the presence of H 2 PO 4 decreased the maximum Zn adsorbed,but increased the bonding energy.Although K + and NH + 4 equally influenced maximum Zn adsorbed,they differed in their effect on the distribution coefficient of Zn in soils.Values of saturation index calculated using Visual MINTEQ indicated that at the low Zn concentration,Zn solubility was controlled by sorption reactions and at the high Zn concentration,it was mainly controlled by sorption and mineral precipitation reactions,such as precipitation of Zn 3(PO 4) 2.4H 2 O,Zn 5(OH) 6(CO 3) 2,and ZnCO 3.For most ionic background electrolytes,soil pH,CaCO 3,and cation exchange capacity(CEC) were significantly correlated with sorption parameters.