污染土壤修复中表面活性剂的应用研究进展

介绍了表面活性剂的种类及主要特征,重点评述了表面活性剂在有机污染、重金属污染和复合污染土壤修复中的国内外最新研究进展,指出了表面活性剂应用于土壤修复中的发展趋势和应关注的问题。     

壳聚糖修复重金属污染土壤的研究进展

壳聚糖是一种来源广泛、具有良好的生物相容性、生物降解性的高分子材料,其含有大量氨基、羟基等活性基团,能与重金属离子进行螯合,发生吸附作用。壳聚糖还具有改良土壤、促进植物生长,诱导植物抗逆的作用,在重金属污染农田土壤修复中具有独特的应用优势。综述了近年来国内外有关壳聚糖修复重金属污染土壤的研究进展,探讨了壳聚糖对土壤重金属污染修复的潜力,阐述了壳聚糖在重金属原位钝化修复、土壤淋洗修复、强化植物提取修复三个方面的应用,并指出壳聚糖在重金属污染土壤修复中存在的问题以及对其在未来修复重金属污染土壤的发展进行了展望,以期为壳聚糖重金属修复技术的推广和应用提供参考。     

化学淋洗和深层土壤固定联合技术修复重金属污染土壤

联合技术用于修复重金属污染土壤是土壤修复领域的研究热点,本研究主要是利用化学试剂淋洗污染土壤,在深层土壤添加固定剂,固定从耕作层淋下来的重金属,旨在形成一种原位修复重金属污染土壤的新方法。     

茶皂素对潮土重金属污染的淋洗修复作用

为了探讨茶皂素淋洗修复土壤重金属污染的可行性,该文采用振荡提取和土柱淋洗的方法,研究了茶皂素对污染土壤中重金属的去除作用。结果表明,茶皂素溶液的浓度和土壤的pH值对重金属去除率有明显影响。土柱淋洗试验中,采用质量分数7%茶皂素溶液作淋洗液,pH 5.0±0.1、土液质量体积比1：4为最佳淋洗修复条件,此时,Pb、Cd、Zn、Cu的去除率分别为6.74%、42.38%、13.07%、8.75%,去除率的大小顺序为Cd＞Zn＞Cu＞Pb。茶皂素淋洗能有效去除酸溶态和可还原态的重金属,从而大大降低了重金属的环境风险,同时说明茶皂素用于土壤重金属污染淋洗修复有较大潜力。     

持久性有机污染场地土壤淋洗法修复研究进展

持久性有机污染场地土壤淋洗法是污染场地土壤物化修复方法中一种常用的技术。淋洗法是指运用特定淋洗剂对污染土壤进行深度洗涤,通过分离净化淋洗剂,实现回用集成,达到去除土壤中污染物的目的,并最终安全化处置污染物和修复土壤的过程。本文根据污染场地土壤处理位置、淋洗剂种类和淋洗剂施用方式的差异,将持久性有机污染场地土壤淋洗法划分为不同的种类;总结了为达到高效去除土壤中污染物质,可运用多级淋洗方式、超声方式、电动力方式和化学氧化等方式实现强化修复效率;阐述了污染场地土壤质地、污染物性质、淋洗剂性质、淋洗条件优化以及淋洗剂回用效率等因素对淋洗修复整体效用的显著影响;同时指出了目前持久性有机污染场地土壤淋洗法存在的问题和今后国内外研究和应用的方向。综合考虑土壤淋洗修复技术适用范围和成本因素,认为淋洗法是一种较符合我国持久性有机污染场地土壤实情的修复技术,具有较强的针对性和较广泛的运用前景。     

酶与茶皂素组合液对重金属Cd和Pb复合污染土壤的生态修复作用

[目的]评价α-淀粉酶与茶皂素对污染土壤中的Cd,Pb洗脱效果,为重金属污染土壤的修复提供更准确的科学依据。[方法]以重金属Cd,Pb污染的耕作层土壤为研究对象,利用α-淀粉酶和茶皂素复合淋洗对Cd,Pb污染土壤进行生态修复,并测定土壤淋洗前后Cd,Pb形态的变化。[结果]在反应时间12h,pH 4.0,反应温度30℃,茶皂素溶液和酶溶液配比4∶1条件下,Cd,Pb去除率分别为88.87%,43.97%。通过对修复前后重金属的形态分析,发现酸提取态、可还原物态的重金属较容易去除,淋洗后土壤中Cd和Pb均达到土壤环境质量Ⅱ级标准。[结论]α-淀粉酶和茶皂素组合对土壤中Cd,Pb有明显的去除效果,起到协同、增强作用。表明α-淀粉酶和茶皂素组合在生态修复重金属污染的土壤方面具有一定的应用前景。     

腐殖酸与活性污泥对污染土壤联合修复研究

采用正交试验的方法,研究了表面活性剂溶出和微生物降解联合作用对重金属铜、锌、铅和多环芳烃菲、萘、芘人工老化污染土壤的修复效率。选择腐殖酸为表面活性剂,强化微生物对有机污染物的降解性能,将高效降解菌的降解能力有效地发挥出来;用驯化的活性污泥为土壤生物修复剂,强化腐殖酸对重金属的洗提作用,旨在降低重金属和多环芳烃在土壤中的污染作用,提高修复效率。结果表明,接种2.0%活性污泥,温度为35℃,pH值为6.5,腐殖酸加入量为5mg/g的土壤为最佳修复条件,在此条件下菲、萘、芘的总修复率分别为73.4%,80.5%和68.2%;重金属离子Cu2+,Zn2+,Pb3+的总修复率分别为75.5%,64.2%和71.7%。添加腐殖酸和驯化活性污泥可明显提高土壤中重金属和多环芳烃的修复效率,表明化学溶出与生物降解同时作用于复合污染土壤具有较好的协同作用。     

重金属污染农田土壤化学钝化修复的稳定性研究进展

化学钝化修复是一种应用广泛的重金属污染农田土壤修复方法,但钝化修复只是暂时降低了土壤中重金属的移动性和生物有效性,随着时间的推移被固定的重金属有可能重新释放到土壤中,因此钝化修复重金属污染土壤的稳定性是重金属污染土壤原位钝化修复成功的关键。本文探讨了钝化修复剂的种类、修复机制、修复稳定性的影响因素以及修复稳定性的研究方法,深入分析了钝化修复稳定性的研究现状和存在问题,并提出今后应加强钝化修复稳定性机制和修复稳定性预测模型的研究,建立和完善科学的钝化修复稳定性的研究方法。     

农田土壤重金属污染化学钝化修复研究进展

土壤重金属化学钝化修复是指向污染土壤中添加钝化剂,使重金属由活性向稳定化形态转化,以降低重金属的迁移和生物可利用性,从而修复重金属污染土壤的方法。本文综述了近些年国内外各类钝化材料修复重金属污染土壤的作用效果和机理、实例等方面的研究进展,并讨论了原位修复土壤重金属中亟待解决的问题,旨在为农田土壤重金属污染的化学钝化剂筛选与应用提供参考依据。     

石灰水对混合试剂洗脱土壤重金属淋洗效果的影响

为了探索石灰水对混合试剂(MC)洗脱后土壤中重金属的淋洗效果,对重金属污染土壤进行了盆栽淋洗试验研究。结果表明:石灰水淋洗MC洗脱土壤,淋出液中Cd、Zn、Pb和Cu浓度均显著高于去离子水淋洗MC洗脱土壤,这主要由于石灰水提高土壤pH,释放土壤所吸附的络合态重金属,这种现象在酸性污染土壤中表现更明显。对于酸性污染土壤,可采用MC+石灰水+去离子水依次进行淋洗处理,其Cd和Zn去除率与MC+去离子水+去离子水依次淋洗处理相比提高22.6%和28.8%;对于中性重金属污染土壤,两处理间重金属去除率差异不显著。石灰水淋洗可提高土壤重金属去除率,并提高土壤pH,改善MC洗脱对土壤的酸化,有利于淋洗后土壤的农业利用。     

pH对磷钾铝石形成的影响

Effects of column temperature and flow rate on separation of organic acids were studied by determining nine low-molecular-weight organic acids on reversed-phase C18 column using high performace liquid chromatography(HPLC) with a wavelength of UV(ultraviolet)214 nm and a mobile phase of 18 mmol L^-1 KH2PO4 buffer solution (pH2.1).The thermal stabiltiy of organic acids was determined by comparing the recoveries of organic acids in different temperature treatments.The relationships between column temperature,flow rate or solvent pH and retention time were analyzed.At low solvent pH,separatioin efficiency of organic acids was increased by raising the flow rate of the solvent because of lowering the retention time or organic acids.High column temperature was unfavorable for the separation of organic acids.The separating effect can be enhanced through reducing column temperature in organic acid determination due to increasing retention time.High thermal stability of organic acids with low concentrations was observed at temperature of 40℃-45℃,Sensitivity and separation effect of organic acid determination by HPLC were clearly improved by a combination of raising flow rate and lowering column temperature at low solvent pH.     

Effect of reducing conditions on P sorption of soils

Abstract

The phosphate sorption (P _sor) capacity of soils increased when the soils were reduced (Willet and Higgins, Aust. J. Soil Res., 16, 319–326, 1978). The present study aimed at the elucidation of this mechanism using Na₂S₂O₄ and 5 different soils. The P _sor of the 5 soils increased with the addition of a small amount of Na₂S₂O₄. Fe(II) was released from the soils with the addition of the same small amount of Na₂S₂O₄. Furthermore, when the amount of FeCl₂ corresponding to the amount of Fe(II) released along with the small amount of Na₂S₂O₄ was added, the P _sor of the soil increased. However, the P _sor of the lowland soils, of which the hydrous Fe oxide content was lower than the others, decreased when the amount of Na₂S₂O₄ addition was increased up to 150–200 g kg^?1. Based on these results, the following process is inferred for the increase in the P _sor of the soils when they are reduced. Hydrous Fe oxide in soil takes the form of very fine, high-density particles and reacts with P mainly on their surface. When a small amount of Na₂S₂O₄ is added, the hydrous Fe oxide is partially reduced, dissolved and finally re-precipitates with P by oxidation with O₂ from the air during the experiment.     

Effect of Timing of Sulfur Fertilizer Application on Growth and Yield of Rapeseed

Abstract

There is usually a positive yield response when sulfur (S) is applied to rapeseed (Brassica rapa L.) plants grown on S-deficient soils. Recommendations include application of some of or the entire amount of S at planting, but the plant requirement as well as availability of S to rapeseed during its various phenological stages is not well documented. In a field trial, 40 kg S ha^?1 was applied as gypsum (CaSO₄·2H₂O) at planting (T₁), during vegetative (T₂, 30 days after sowing), flowering (T₃, 50 days after sowing), and pod-filling (T₄, 65 days after sowing) stages, and in split doses (T₅). Biomass accumulation, leaf-area index, and leaf photosynthetic rate were studied at various growth stages. Seed S (sulfate and organic S) and yield parameters were studied at harvest. Sulfur (40 kg S ha^{? 1}) applied in three split doses during different growth stages caused maximum increase in these parameters, followed by T₂ and T₁. However, no significant discernable difference was observed for the application at planting (T₁) and during vegetative stage (T₂). No significant response was seen following the application of T₃ and T₄ when compared with the control (T₀). On the basis of these results, we concluded that application of S fertilizer in split doses during growth stages is better than application of the entire amount of S at any stage for obtaining optimum yield of rapeseed.     

氮磷钾配比对木薯养分吸收动态及产量影响

【目的】木薯是重要的粮食作物,也是优质的淀粉工业原材料,被认为是非粮生物质能源的最合适原料。氮、 磷、 钾含量水平显著影响木薯产量,但有关木薯养分阶段性累积特征及其对生物量和产量形成影响的相关研究仍较少。本文比较了不同肥料配比情况下,木薯生物量, 氮、 磷、 钾累积量变化趋势,探讨了不同生育期氮、 磷、 钾含量及累积量的重要性及施肥对其影响。【方法】以我国主栽木薯品种华南205为材料,2009年在广东省郁南县丘陵坡地开展田间施肥试验,共设CK、 NP、 NK、 PK、 NPK 5个施肥处理。于苗期、 块根形成期、 块根生长早期、 块根快速膨大期和成熟期调查生物量和氮、 磷、 钾含量,得出氮、 磷、 钾累积动态。以各时期氮、 磷、 钾含量及累积量作为原始变量进行主成分分析,判断各时期氮、 磷、 钾含量及累积量的重要性,并分析不同肥料配比对各时期氮、 磷、 钾含量及累积量的影响。【结果】华南205的生物量累积动态呈S型曲线, 生物量在苗期较小,进入块根形成期后快速提高,当进入成熟期后增长逐渐减缓。氮肥对生物量影响最大,其次是钾肥,磷肥的影响最小。木薯氮含量的变幅为3.99%~0.93%, 磷含量为0.82%~0.26%, 钾含量为1.39%~0.89%。氮、 磷、 钾含量均在苗期最高,且随着生育期的推进不断降低,尤以氮含量降幅最大。不同氮、 磷、 钾肥料配比显著影响木薯的氮、 磷、 钾含量。PK处理的氮含量较NPK处理降低了32.96%,NK处理的磷含量较NPK处理降低了16.21%,NP处理的钾含量较NPK处理降低了50.37%。氮、 磷、 钾累积量与产量显著相关。主成分分析表明木薯整个生育期的营养状况与块根形成期的氮含量、 苗期的钾含量及块根生长阶段的磷含量相关性最大。氮、 磷、 钾的吸收累积量随着木薯生长不断提高,其中块根形成期、 块根生长早期、 块根快速膨大期的氮累积量较大,块根形成期、 块根快速膨大期的磷累积量较大,块根生长早期、 块根快速膨大期、 成熟期的钾累积量较大。主成分分析表明块根快速膨大期的氮、 磷、 钾累积量对整个生育期养分累积影响显著,同时,苗期及块根生长早期的氮、 钾累积量对养分累积总量影响也较大。【结论】木薯氮、 磷、 钾含量随着植株生长不断下降,而累积量却不断提高。不同氮、 磷、 钾肥料配比显著影响木薯的氮磷钾含量及累积量、 物质累积及产量形成,其中氮肥的影响最大,其次是钾肥,磷肥的影响最小。综合分析表明,苗期、 块根形成期、 块根生长早期为氮、 磷肥的最佳施用时期,块根形成期、 块根生长早期及块根快速膨大期为钾肥的补充阶段。     

Medium-term effects of a single application of mustard residues on soil microbiota and C content of vertisols

 A study of the effects of different qualities (fresh and composted) and rates (equivalent to 120, 240, and 360 kg N ha^–1) of mustard meal application on wheat yields on humid tropical vertisol was started in 1990 at Ginchi Research Station in Ethiopia. After continuous wheat cropping for 7 years and without any further fertilisation, soil microbial parameters (basal respiration, microbial biomass-C and N, organic-C, and ecophysiological quotients) were studied during one growth period. After 7 years of application, mustard meal still exerted a significant positive effect on microbial biomass, basal respiration, organic-C, C_mic : N_mic ratio, and metabolic quotient (qCO₂). Organic-C, qCO₂ and C_mic : N_mic ratios were higher for the compost-amended plots than plots amended with fresh mustard meal. Basal respiration, C_mic, and C_mic : N_mic ratio showed a clear seasonality, but only in manured plots. The data indicate shifts in microbial community structure (from bacteria to fungi and from r to K strategists) and suggest positive medium-term effects of mustard meal on humid tropical vertisol biological qualities. Received: 25 May 1999     

华蓥市山区典型林分水源涵养功能评价

为研究南方丘陵山区典型人工林的生长现状和涵养水源能力,选取华蓥市6种林分作为研究对象,通过测定林下枯落物层和土壤层特征,分析比较不同林地枯落物和土壤的持水能力,对林地水源涵养能力进行评价。结果表明:杉木纯林(近自然经营)枯落物现存蓄积量最大,枯落物持水能力排序为杉木纯林(近自然经营)杉木纯林马尾松—檵木混交林(近自然经营)杉木—响叶杨混交林柏木纯林马尾松—杉木混交林;杉木纯林的土壤层总孔隙度、毛管孔隙度、有效持水量均为最优,分别达到67.67%,60.39%,138.11 t/hm~2;6种林地土壤有效持水量大小顺序为杉木纯林杉木纯林(近自然经营)马尾松—杉木混交林杉木—响叶杨混交林柏木纯林马尾松—檵木混交林(近自然经营);综合枯落物层和土壤层持水能力可知,杉木纯林(近自然经营)的水源涵养能力最强,为309.77 t/hm~2,马尾松—杉木混交林最弱。     

华北土石山区天然植被种间联结和生态位研究

 在华北土石山区潮关西沟流域天然森林植被调查的基础上,对森林植被群落种间联结和生态位进行研究。结果表明:种间正联结关系非常显著的有柞栎和蒙椴、柞栎和迎红杜鹃、蒙椴和山杨、蒙椴和白蜡、山杨和白蜡、春榆和北京丁香、春榆和大花溲疏、臭椿和山杏、臭檀和栾树、臭檀和大花溲疏、锐齿鼠李和孩儿拳头、小叶鼠李和酸枣。另外,依据种间联结关系,划分了4个生态种组。分析了主要乔灌木的生态位宽度,乔木树种蒙椴、柞栎、春榆和灌木树种荆条、小叶朴和酸枣的生态位宽度均较大。比较了不同种对的生态位重叠指数,乔木不同种对中,山杏和北京丁香、柞栎和白蜡、蒙椴和春榆具有较大的生态位重叠,灌木不同种对组合中,荆条和酸枣、绣线菊和迎红杜鹃、荆条和小叶朴、蚂蚱腿子和迎红杜鹃的生态位重叠较大。     

Use of Two-Surface Langmuir-Type Equations for Assessment of Phosphorus Requirements of Lentil on Differently Textured Alluvial Soils

If soil solution phosphorus (P) optimum levels for plant growth (external P) are known, P adsorption isotherms or their equations could further be used to assess how much fertilizer P may be needed for optimum plants yield (QFPN) by adjusting this known external solution P requirement in the soil (ESPR). Surface soil samples were collected from a farmer's field area and research area. An adsorption study was conducted on Ustic Endoaquerts (S₁ soil), Typic Calciargids (S₂ soil), and Typic Torripsamments (S₃ soil) to develop the two-surface Langmuir-type equations. Phosphorus adsorption data were obtained by equilibrating 10-g soil samples in 100 mL of 0.01 M calcium chloride (CaCl₂) containing various amounts of monopotassium phosphate (KH₂PO₄). Thereafter, 11 P fertilizer rates were calculated by two-surface Langmuir-type equations to adjust different estimated soil solution P levels (EPAS) that were designated as treatments (0.05 to 0.90 mg L^?1). Then field experiments on lentil (cv. Niab Masoor 2002) were conducted according to a randomized complete block design (RCBD) on these soils to determine internal (plant tissue), external (soil solution), and fertilizer P requirements. Maximum lentil seed yield (Mg ha^?1) was 0.87 with T₄ (0.17 mg P L^?1) in S₁ soil, 1.8 with T₃ (0.20 mg P L^?1) in S₂ soil, and 0.73 with T₇ (0.28 mg P L^?1) in S₃ soil, obtained by applying 170 kg P₂O₅ ha^?1 in S₁ soil, 110 kg P₂O₅ ha^?1 in S₂ soil, and 78 kg P₂O₅ ha^?1 in S₃ soil. Internal P concentrations (%) of the whole plant associated with 95% of maximum lentil seed yield at flowering stage were 0.245, 0.210, and 0.315 in S₁, S₂, and S₃ soils, respectively. Internal P requirements of lentil seed were 0.290 in S₁, 0.245% in S₂, and 0.380% in S₃ soil. The ESPRs for 95% of maximum yield of lentil were 0.16 mg L^?1, in S₁ soil, 0.23 mg L^?1 in S₂ soil, and 0.27 mg L^?1 in S₃ soil. The QFPN estimated from graphs corresponding to these ESPR values were 160 kg P₂O₅ ha^?1 in S₁ soil, 125 kg P₂O₅ ha^?1 in S₂ soil, and 74 kg P₂O₅ ha^?1 in S₃ soil. The QFPNs estimated from corresponding two-surface Langmuir-type equation by using respective ESPR values were 164, 127, and 75 kg P₂O₅ ha^?1 in S₁, S₂, and S₃ soil, respectively. Field-applied P₂O₅ amounts to adjust soil solution P levels (mg L^?1) at 0.166 (T₄), 0.229 (T₄), and 0.281 (T₇) were 170, 126, and 78 kg ha^?1 in S₁, S₂, and S₃ soil, respectively. Based on the results of these studies, we propose that QFPNs estimated by graphs against identified ESPR values or calculated by the use of corresponding two-surface Langmuir-type equations are in close proximity to the field-applied P to adjust desired EPAS value. Therefore, either of the two techniques may be used to estimate QFPN for optimum lentil yield. Close     

浙江省天台县不同森林类型枯落物及土壤水文特性

[目的]掌握浙江省天台县不同森林枯落物和土壤的持水能力,为该区域今后在森林水源涵养等方面提供科学依据。[方法]采用野外调查和室内浸泡法,对天台县8种森林类型(毛竹林、阔叶混交林、针阔混交林、针叶混交林、马尾松林、杉木林、黑松林、木荷林)枯落物及林下土壤持水性进行了研究。[结果] 8种森林类型的枯落物蓄积量在8.05～23.84 t/hm~2之间;最大持水量变化范围为14.59～35.15 t/hm~2,其大小排序为:木荷林针阔混交林阔叶混交林马尾松林杉木林黑松林毛竹林针叶混交林;8种森林类型林下枯落物持水量与浸泡时间之间变化规律基本一致,持水量与浸泡时间呈对数函数关系,不同森林类型林下枯落物吸水速率与浸泡时间呈幂函数关系;各森林类型土壤容重介于0.83～1.21 g/cm~3,土壤持水力变化范围为200.74～575.70 t/hm~2,其大小依次为:黑松林针阔混交林木荷林杉木林毛竹林马尾松林阔叶混交林针叶混交林。[结论]阔叶林以及含有阔叶树种的森林类型枯落物以及林下土壤持水能力均较强,其中土壤持水能力最强的为黑松林。     

CMA staining analysis of chromosomes in several species of Aurantioideae

Fluorochrome staining with chromomycin A₃ (CMA) was used to characterize and compare the CMA banding patterns of chromosomes of 17 species from 13 genera of Aurantioideae, which is one of the seven subfamilies of Rutaceae. All species used in this study had 2n = 18 chromosomes. These chromosomes were classified into five types based on the number and position of CMA-positive bands; B: one telomeric and one proximal band, C: two telomeric bands, D: one telomeric band, E: without bands and Dst: type D with a satellite chromosome. Each species possessed two or four types of chromosomes and unique CMA banding patterns. The CMA banding patterns were 6D + 12E in Clausena anisata (Willd.) Hook. f.,1C + 3D + 14E in Murraya koenigii (L.) Spreng., 1C + 11D + 6E in Murraya paniculata (L.) Jack, 1B + 1C + 10D + 6E in Merrillia caloxylon (Ridl.) Swing., 1C + 9D + 7E + 1Dst in Paramignya lobata Burkill, 2C + 5D + 11E in Severinia buxifolia (Poir.) Tenore, 5D + 13E in Hesperethusa crenulata (Roxb.) Roem., 16D + 2E in Citropsis gabunensis (Engl.) Swing. et M. Kell, 14D + 4E in Citropsis schweinfurthii (Engl.) Swing. et M. Kell, 8D + 10E in Atalantia monophylla DC., 1C + 3D + 14E in Atalantia ceylanica (Arn.) Oliv., 2D + 16E in Atalantia roxburghiana Hook. f., 18E in Swinglea glutinosa (Blanco) Merr., 2D + 16E in Aegle marmelos (L.) Corr., 4D + 14E in Afraegle paniculata (Schum.) Engl., 2B + 2D + 13E + 2Dst in Feronia limonia (L.) Swing. and 3B + 9D + 6E in Feroniella oblata Swing. The advanced genera in each tribe and subtribe such as Merrillia and Feroniella showed heterochromatin (CMA-positive bands) rich chromosome configuration in general. Swinglea glutinosa without heterochromatin rich chromosome, which is considered to be the most primitive chromosome configuration, seems to be the key genus for clarifying the evolution of the tribe Citreae.