土壤锌、铁、铜、锰形态的分布及其与植物有效性的关系

The distribution of various fractions of Zn,Fe,Cu and Mn in 15 types of soils in China and its relationship with plant availability were studied.Fractions of various elements were found to have some similar characterstic distribution regularities in various types of soils,but various soil types differed to varying degrees in the distribution of each fraction.Soil physico-chemical properties,such as pH,CEC and the contents of OM,CaCO3,free Fe,free Mn and P2O5,were significantly correlated with the distribution of elemental fractions,and a significant correlation also existed between the distribution and plant availability of elemental fractions.Various fractions of each element were divided into two groups based on their plant availability.The correlation between the distribution of combination fractions and plat availability indicated a significantly or an extremely significantly positive correlation for Group I but a significantly or an extremely significantly negative correlation for Group II.Therefore,the fractions in Goup I were primary pools of available nutrients,while those in Group II could hardly provide available nutrients for plants.Decreasing the transformation of corresponding elements into fractions of Group II and increasing the storage capacity of various fractions of Group I were an important direction for regulation and controlling of soil nutrients.However,some Particular soils with too high contents of Zn,Fe,Cu and Mn should be regulated and controlled adversely.     

Comparisons of soil test phosphorus by Olsen,Bray P1, Mehlich I and Mehlich III methods

Abstract

A study was undertaken to evaluate the agreement among different university laboratories performing the Olsen, Bray P1, and Mehlich I tests for P on a diverse group of noncalcareous agricultural soils and to develop relationships among the Olsen, Bray P1, Mehlich I, and Mehlich III soil tests. For each test, the results from the individual laboratories were highly correlated (r² ≥ 0.90) and in almost all instances the slopes of the equations describing the relationships among laboratories approached one, The results indicate that the Olsen, Bray P1 and Mehlich I soil tests may be performed with a high degree of precision when standard soil test procedures are followed.

Of the three most commonly performed tests in the U.S. (Olsen, Bray P1, and Mehlich I), the Olsen and Mehlich I tests were the most highly correlated (r² = 0.87) although the Mehlich I test removed approximately one and one half times more P than did the Olsen test. Bray P1 and Olsen and Mehlich I P were less highly correlated (r² ≤ 0.72) and the relationships between these variables were influenced by the texture of the soils. The quantity of P removed by the Bray P1 test was on the order of two and three times greater than that removed by the Olsen and Mehlich I tests, respectively. The Bray P1 and Mehlich III soil tests were highly correlated (r² = 0.97) and similar quantities of P were extracted from the soil by the two tests.     

种植制度和施肥对半干旱区土壤中锰形态及有效性的影响

Manganese(Mn) deficiencies are common in soils on the Loess Plateau of China. This research provided essential information on improving Mn availability in semiarid soils through agricultural practices. Twelve cropping system and fertilization treatments were designed in a 28-year experiment. The cropping systems included long-term fallow, continuous winter wheat cropping, pea(1 year)-winter wheat(2 years)-millet(1 year) rotation(crop-legume rotation) cropping, and continuous alfalfa cropping. The fertilizer treatments under the cropping systems included no-fertilizer control(CK), application of P fertilizer(P), application of N and P fertilizers(NP), and application of N and P fertilizers and manure(NPM), but the NP treatment was excluded in the continuous alfalfa cropping system. Available Mn and Mn fractions of soil samples(0–20 and 20–40 cm depths) were measured and further analyzed quantitatively using path analyses. Results showed that the crop-legume rotation and continuous alfalfa cropping systems significantly increased available Mn compared with the fallow soil. Compared with the no-fertilizer control, manure application increased available Mn in soil of the continuous wheat cropping system. Across all treatments, the averaged content of mineral-, oxide-, carbonateand organic matter-bound and exchangeable Mn accounted for 42.08%, 38.59%, 10.05%, 4.59%, and 0.09% of the total Mn in soil,respectively. Cropping significantly increased exchangeable Mn in soil and the highest increase was 185.7% in the continuous wheat cropping system at 0–20 cm depth, compared with the fallow soil. Fertilization generally increased exchangeable and carbonate-bound Mn in soil. Carbonate-bound Mn was the main and direct source of available Mn in soil, followed by exchangeable and organic matterbound Mn. These results indicated that crop-legume rotation cropping, continuous alfalfa cropping and application of manure, have the potential to promote Mn availability in soils of rainfed farmlands.     

秸秆还田对砂姜黑土理化性质与锰、锌、铜有效性的影响

采用田间试验与实验室培育试验研究作物秸秆还田对砂姜黑土理化性质及Cu、Zn、Mn有效性的影响,结果表明,秸秆还田可降低土壤容重,增大土壤总孔隙度,特别是毛管孔隙度显著增加。土壤中胡敏酸和富里酸含量显著增加,胡敏酸含量的增加对提高土壤有机质活性和改善土壤肥力具有良好效应。与单施化肥比较,秸秆配施化肥土壤中交换态锰、锌、铜含量分别增加11%、21%和41%,有机结合态锰、铜分别增加19%和103%。培育试验表明,加入粉碎的作物秸秆培育90d后,土壤中有效锰、有效铜含量分别增加21%和27%。     

三江平原白浆土中Fe、Mn、Cu和Zn生物有效性的研究

在三江平原上,测定 42 个小区中玉米、大豆、小麦籽实 Fe、Mn、Cu 和 Zn 含量和土壤中各形态 Fe、Mn、Cu 和Zn含量.通过相关分析和通径分析,探讨了土壤中各形态Fe、Mn、Cu 和 Zn 的生物有效性,旨在为该地区合理施用微量元素提供科学依据.试验结果表明,玉米、大豆和小麦籽实含 Fe、Mn、Cu 和 Zn 量与土壤中有效态和交换态 Fe、Mn、Cu和Zn含量呈显著或极显著正相关.有机态 Fe、Mn、Cu 和 Zn含量与玉米、大豆和小麦籽实Fe、Mn、Cu 和 Zn含量也有很好的相关关系.交换态对有效态 Fe、Mn、Cu 和 Zn 影响最大,其次是有机质结合态.铁锰氧化物结合态 Fe、Cu 对有效态 Fe、Cu 及碳酸盐结合态 Mn、Zn 对有效态 Mn、Zn 具有一定正效应.而残留态 Fe、Cu 对有效态 Fe、Cu 和铁锰氧化物结合态 Mn 对有效态 Mn 产生负效应.     

Long-term impacts of zinc and copper enriched sewage sludge additions on bacterial, archaeal and fungal communities in arable and grassland soils

Long-term impacts of metal contamination derived from sewage sludge on soil microbial communities have been widely evaluated, but confounding effects have made it difficult to draw firm conclusions and thus to advise on safe metal limits. Here we used Multiplex-terminal restriction length fragment polymorphism (M-TRFLP) to assess the long-term impact of sludge-borne Zn and Cu contamination on the structure of bacterial, fungal and archaeal communities across seven different soils at metal levels relevant to current guideline limits. Despite strong effects of site on microbial community structure, analysis of similarity (ANOSIM) demonstrated a small but significant effect of Zn on bacteria (P < 0.001), archaea (P < 0.001), and fungi (P < 0.001). Significant effects of Cu on bacteria (P < 0.001), archaea (P < 0.001) and fungi (P < 0.001) were also observed. Several bacterial and fungal T-RFs were identified as responding to Zn or Cu. For example the bacterial T-RF 72 was negatively correlated with Zn and Cu, and T-RF 259 was positively correlated with Zn. Attempts to identify these bacterial markers of Zn and Cu contamination suggest a negative impact of Cu on Acidobacteria in arable soils. These results demonstrate for the first time, that despite a strong influence of site on microbial community structure, effects of Zn and Cu derived from sewage sludge can be detected as shifts in bacterial, fungal and archaeal communities indicating a common response more than 11 years after sludge addition.     

Effects of Sesbania rostrata and Azolla microphylla incorporation on transformation of applied zinc and copper in lateritic rice soils with different flooding regimes

Fixation of Zn and Cu applied to tropical rice-growing lateritic soils rich in Fe-oxides may be reduced if the soils are kept flooded for a few days before their application. There may be a further reduction if such flooding is combined with incorporation of green manures. To investigate this effect, a laboratory experiment was conducted to study the effect of different periods (0 and 15 days) of preflooding combined with (0 and 0.50% of soil weight) Sesbania rostrata and Azolla microphylla incorporation as green manures on the transformation of applied Zn and Cu in two lateritic rice-growing soils. Recovery of added Zn/Cu in DTPA (diethylene triamine pentaacetate)-extractable form was always found to be higher when they were applied after the soils were maintained in a flooded state for 15 days than when applied immediately after flooding; this effect was more prominent in respect of Cu. Contrary to expectations, green manure incorporation along with preflooding caused a significant decrease in recovery of Zn/Cu; the effect, however, showed a decreasing trend as incubation progressed. The effect was more marked with A. microphylla than with S. rostrata, particularly with Cu. Possible causes of such changes and their implications on the Zn/Cu nutrition of rice are discussed. Received: 7 August 1995     

The profile distribution of total and extractable copper in selected Nigerian soils

Abstract

The profile distribution of total, DTPA‐ and 0.1N HCl‐extractable Cu was determined in 11 Nigerian soil profiles formed from various parent materials including the coastal plain sands, shales, basalt, granite and banded gneiss.

Total Cu ranged from 7 to 72 ppm with a mean of 35 ppm₀ The soils formed from basalt had the highest values while those on coastal plains had the least content. Generally, there was a higher content in the subsoils than in the surface horizons. The total Cu significantly correlated with percent clay and the free oxide contents of Fe and Mn.

DTPA ‐ and 0.1N HCl‐extractable Cu ranged from 0.08 to 2.81 ppm and 0.10 to 7.78 ppm, respectively. Soils on metamorphic rocks gave the highest values of DTPA‐extractable Cu. The DTPA‐extractable Cu ‐was only related to pH but the acid extractable Cu was associated with total Cu, clay, free Fe₂O₃ and MnO₂ contents.     

干旱区绿洲灌漠土对铜的吸附解吸特性研究

土壤对重金属的吸附解吸是影响土壤系统中重金属的移动性和归宿的主要过程.本文使用序批实验方法、单步提取方法、连续提取方法等研究了干旱区绿洲灌漠土Cu的吸附解吸特性.结果表明,灌漠土对Cu的吸附等温线可很好地用Freundlich等温方程拟合,灌漠土的Cu吸附可能受土壤理化综合因素影响,而不仅是某个土壤理化指标所控制;二次...     

不同参龄人参及其根际土壤中Cu、Zn、Mn含量研究

通过对不同参龄人参药材与根际土壤中Cu、Zn、Mn3种微量元素动态变化特征的分析,探讨人参与土壤中微量元素间的相互关系,找出人参对Cu、Zn、Mn的吸收积累规律和参地土壤Cu、Zn、Mn含量的变化规律,为确定人参适宜的生产环境和建立标准化的田间管理提供依据,结果表明,人参根际土壤中Cu含量随人参种植年限的增加有明显的累积趋势,该人参基地土壤Zn含量偏低,应适当施用Zn肥来提高土壤Zn含量;7月份是各参龄人参药材Cu含量和单株根Cu积累量增加最快的时期,7、8月份是各参龄人参药材Mn含量和单株根Mn积累量增加最快的时期,9月份是6年生人参对Zn元素需求旺盛的时期,在整个人参生长期,6年生人参药材Cu、Mn、Zn含量和单株根积累量都高于4、5年生人参,在本试验的采样年限内,以生长6年为最佳采收年限。     

我国主要麦区土壤有效铁锰铜锌丰缺状况评价及影响因素

明确我国主要麦区土壤有效铁锰铜锌含量分布和影响因素，对了解麦田土壤微量元素供应能力、指导小麦丰产与优质生产至关重要。于2016—2021年连续6年，在我国17个小麦主产省/市采集1 314份耕层土壤样品，参考中国土壤有效微量元素分级标准，评价了我国麦田土壤有效铁锰铜锌丰缺状况，并采用随机森林方法定量分析了主要土壤化学性质对铁锰铜锌有效性的贡献。结果表明，我国主要麦区土壤有效铁含量介于1.8~612 mg?kg-1，平均为49.1 mg?kg-1，8.9%的样本未达到缺铁临界值4.5 mg?kg-1，且主要集中在北方、西北麦区的山西、陕西、甘肃等地，西南和长江中下游麦区有效铁较高。土壤有效锰介于0.1~176 mg?kg-1，平均为22.1 mg?kg-1，低于缺锰临界值5 mg?kg-1的样本占6.9%，缺锰土壤分布在西北、北方麦区的山西、陕西、甘肃、内蒙古等地，西南、长江中下游麦区土壤有效锰含量较高。土壤有效铜介于0.1~10.8 mg?kg-1，平均为1.9 mg?kg-1，仅1.8%样本未达到缺铜临界值0.5 mg?kg-1。土壤有效锌介于0.1~26.0 mg?kg-1，平均为1.4 mg?kg-1，14.3%的样本低于缺锌临界值0.5 mg?kg-1，主要分布在西北和北方麦区的山西、陕西、甘肃、内蒙古等省份，云南、贵州等西南麦区的有效锌较高。土壤基本化学性质中，pH对有效铁、有效锰含量影响最大，有效铁是铜有效性的重要因素，影响有效锌的主要因素是有效磷和有效铜。我国麦田土壤有效铁锰铜锌含量存在较大的区域变异，铁、锰、锌不足主要发生在北方石灰性土壤，南方麦田供应充足，几乎所有麦田土壤有效铜可满足作物铜需求。     

氮锌配施对不同冬小麦品种产量及锌营养的影响

为比较石灰性土壤氮锌配施对不同小麦品种生长及锌营养的影响,选10种本地主要种植小麦品种,进行连续两年的田间试验,测定小麦产量及锌含量。结果表明,在石灰性土壤上单施锌肥和氮锌配施对小麦产量、籽粒锌含量的影响因品种而异。单施锌肥及氮锌配施处理可显著增加土壤有效锌含量,但单施锌肥处理仅增加"西杂1号"、"武农148"、"郑麦9023"籽粒锌含量;氮锌配施增加除"小偃22"外其余9种供试小麦品种籽粒锌含量,增幅为7.3%～54.7%。单施锌肥对小麦锌累积量增加的效果不明显;氮锌配施可显著增加小麦地上部锌累积量,两季分别增加6.5%、29.8%。单施氮肥可显著增加小麦锌吸收,但其主要累积在小麦茎叶部。在石灰性土壤上,单施锌肥虽显著增加了土壤有效锌含量,但对小麦产量及籽粒Zn含量增加有限,氮锌肥配施可取得较好效果。     

Sour Orange (Citrus Aurantium L.) Growth is Strongly Mycorrhizal Dependent in Terms of Phosphorus (P) Nutrition Rather than Zinc (Zn)

The partial sterilization of soil eliminates useful microorganisms, resulting in the reduced growth of mycorrhizae-dependent citrus plants, which are often unresponsive to the application of fertilizer. Research was conducted to test the hypothesis that indigenous mycorrhizae (IM) inoculation is as efficient as selected mycorrhizal inoculation under sterile and non-sterile soil conditions. Rhizophagus clarus and indigenous mycorrhiza spores, isolated from citrus orchards, were used as arbuscular mycorrhizae fungi under greenhouse conditions with sterile and non-sterile Çanakçi series (Typic xerofluvent) soils with low phosphorus (P) fertility. Different P (0 and 100 mg kg^?1) and zinc (Zn) (0, 5 and 10 mg kg^?1) concentrations were used at the start of the experiments. The shoot, root dry weight (RDW), root colonization, and P, Zn, iron (Fe), copper (Cu) and manganese (Mn) concentrations of the shoot were determined; mycorrhizae dependency (MD) was also calculated.

The results indicate that R. clarus and indigenous mycorrhiza in sterile and non-sterile soil conditions considerably increased the growth of citrus plants. Owing to existing beneficial indigenous rhizosphere microorganisms, citrus plant growth without inoculation was better in non-sterile soils than in the sterile soils. In non-sterilized soil, the plant growth parameters of R. clarus-inoculated soils were higher than those of indigenous mycorrhiza-inoculated soils. Mycorrhizae infection increased certain citrus plant growth parameters, such as root infection, biomass and nutrient uptake (P, Zn, Fe, Mn and Cu). In sterile soil, the addition of up to 5 mg kg^?1 soil Zn and the inoculation of R. clarus significantly increased plant growth; inoculation with indigenous mycorrhiza produced more dry weight upon the addition of up to 100 mg kg^?1 phosphorus pentoxide (P₂O₅). Under sterile soil conditions, without considering fertilizer addition, MD was found to be higher than that of non-sterile soils. In general, the contribution of the indigenous soil spores is significant. However, indigenous soil mycorrhizae may need to be managed for better efficiency in increasing plant growth and nutrient uptake. The major finding was that the inoculation of citrus seedlings with mycorrhiza is necessary under both sterilized and non-sterilized soil conditions.     

固、液态磷源在石灰性土壤中的移动性及其对土壤有效磷含量影响的研究

采用同心圆扩散法对固体和酸性液体磷肥在石灰性土壤中的移动性与有效性进行研究。结果表明,土壤Olsen-P含量随施肥点圈层由内向外层而递减,液肥处理的Olsen-P量在施肥点以外的3个土壤圈层中均高于固肥处理。固体肥料大部分停留在距施肥点0~7.5 mm圈层,占施磷总量的55%~70%;液体肥料虽在0~7.5 mm层的含量低于固体肥料(约占15%~40%),但在远离施肥点的后3个圈层(7.5~43 mm)中均高于固体肥料处理,其中7.5~13.5 mm最为明显(液肥占35%,固肥占20%)。3种施磷量在砂土、壤土及粘土上均表现出一致的变化规律。肥料对土壤pH值的影响仅限制在距施肥点最近的0~7.5 mm范围,该层的pH值显著低于后层。本研究说明在石灰性土壤中液体磷的移动性、有效性明显高于固体磷,但对土壤pH值无显著影响。     

Aluminum,manganese, and iron tolerance improves performance of wheat genotypes in waterlogged acidic soils

Waterlogging results in high shoot concentrations of iron (Fe), aluminum (Al), and manganese (Mn) in wheat grown in acidic soil. The verification of this observation in several acidic soils, development of screening techniques, and identification of genotypes differing in tolerance made it possible to test whether tolerance of ion toxicities improves performance of wheat in waterlogged acid soils. Six wheat varieties selected for tolerance/intolerance of Al, Mn, and Fe were grown in three acidic soils (pH_CaCl2 4.1–4.3) with or without waterlogging for 40 d. In terms of relative shoot dry weight, Al‐, Mn‐, and Fe‐tolerant genotypes tolerated waterlogging better, outperforming intolerant genotypes by 35%, 53%, and 32%, respectively, across the soils. The Al‐tolerant genotype had up to 1.8‐fold better root growth than the intolerant genotype under waterlogging. Waterlogging increased DTPA‐extractable soil Mn (71%) and Fe (89%), and increased shoot Fe (up to 7.6‐fold) and Al (up to 5.9‐fold) for different genotypes and soils. The Al‐tolerant genotype maintained lower tissue concentrations of Al as compared to intolerant genotypes during waterlogging. Waterlogging delayed crop development but distinctly less so in the tolerant than in the intolerant genotypes, thus jeopardizing the capacity of intolerant genotypes to produce yield in Mediterranean climates with dry finish of the season. Pyramiding multiple ion tolerances into current wheat varieties with desirable agronomic and quality characteristics to enhance their performance under waterlogged acid soils should be considered.     

Manganese toxicity in bush bean as affected by concentration of manganese and iron in the nutrient solution

An experiment was conducted to clarify the relationship between Mn toxicity and Fe deficiency in bush snap bean (Phaseolus vulgaris L. cv. ‘Wonder Crop No. 2'). Seedlings were grown in full strength Hoagland No. 2 solution at pH 6.0 for ten days. Six concentrations of Mn as MnCl₂.4H₂O were used in combination with three concentrations of Fe as FeEDTA.

Toxicity symptoms, induced by low levels of Mn (0.1 ppm and above), included: small brown necrotic spots and veinal necrosis on primary leaves; necrosis on primary leaf petioles; interveinal chlorosis, with or without brown necrotic spots, on trifoliate leaves; and brown necrotic spots on stipules. Manganese toxicity symptoms were alleviated or prevented by increasing Fe concentration in the nutrient solution.

Manganese concentration in the leaves increased with increasing Mn and decreased with increasing Fe concentration in the nutrient solution, Iron concentration in the roots increased with increasing Fe concentration in the nutrient solution; however, Fe concentration in the leaves was not significantly affected by increasing Mn concentration in the solution culture. Manganese toxicity symptoms developed when Mn concentration in the leaves reached about 120 ppm.

A decrease in the Fe/Mn ratio in the nutrient solution resulted in a proportionate decrease in that of the leaves. Manganese toxicity symptoms occurred when the Fe/Mn ratio in the solution was 10.0 and below, or when the ratio in the leaves was less than 1.5. The ratio of Fe/Mn in the solution required for optimum growth of ‘Wonder Crop No. 2’ bean, without Mn toxicity symptoms, was in the range of 20.0 to 25.0.

Results indicate that the chlorosis on bush bean leaves induced by excessive Mn in the nutrient solution was due to excessive accumulation of Mn and not to Fe deficiency.     

Long-term effects of tillage on the availability of iron, copper, manganese, and zinc in a Spanish Vertisol

Organic matter accumulation and increased microbial activity under no-till can affect the dynamics of some essential micronutrients for plants. The main purpose of this work was to study the long-term effect of tillage on the availability of Fe, Mn, Cu, and Zn in a calcareous soil from Southern Spain. To this end, nutrient availability in surface soil (0–5-cm depth) subjected to a long-term tillage experiment (21 years) was evaluated via pot experiments and chemical tests involving DTPA extraction (as availability index) and sequential chemical fractionation of Mn and Fe.Soil organic matter (SOM) content and microbial activity (estimated by the β-glucosidase method) were found to be significantly higher under no-till (NT) than under conventional (CT) or minimum tillage (MT). Also, DTPA extractable Mn, Cu, and Zn, and citrate–bicarbonate extractable Mn (Mn_cb), were all higher under NT than under CT and MT, the differences being related to the increase in SOM as revealed by the correlation of Mn, Cu, and Zn extractable with DTPA and SOM (r = 0.87, P < 0.001; r = 0.8, P < 0.01, and r = 0.86, P < 0.001, respectively), and that between Mn_cb and SOM (r = 0.87, P < 0.001). However, the increased extractability resulted in no increased concentrations of these nutrients in plants. Moreover, the Mn concentration in the last expanded leaf was significantly lower with NT than with CT, which can be ascribed at least partly to an increased microbial activity under NT as revealed by the negative correlation between Mn in plants and β-glucosidase activity in soil (r = −0.71, P < 0.01). The Fe concentration in plants was not affected by soil tillage; also, it was only related to citrate–ascorbate extractable Fe (r = 0.69, P < 0.05), which exposes the contribution of poorly crystalline Fe oxides in soil to Fe nutrition in plants.     

长期使用含铜杀真菌剂对苹果园土壤中自由态铜离子、固相铜形态分级以及微生物活性的影响

Soil samples were collected from apple orchards 5,15,20,30,and 45 years old,and one adjacent forest soil was used as reference to investigate the free Cu2+ion activity in soil solution and the soil Cu fractionation in the solid phase following long-term application of copper fungicide,Bordeaux mixture,in apple orchards and to investigate the relationships among soil free Cu2+ions,Cu fractionation and soil microbial parameters.The total Cu concentration in the orchard soils varied from 21.8 to 141 mg kg-1,increasing with the orchard age,and the value for the reference soil was 12.5 mg kg-1.The free Cu2+ion concentrations in the soil solutions extracted by 0.01 mol L-1 KNO3 ranged from 3.13×10-8(reference)to 4.08×10-6 mol L-1(45 years-old orchard).The concentration of Cu complexed in the fulvic fraction increased with orchard age from 5.16 to 52.5 mg kg-1.This was also the case for other soil Cu fractions except the residual one.The residual soil Cu remained practically constant,ranging from 4.28 to 5.66 mg kg-1,suggesting that anthropogenic soil Cu mainly existed in the more labile active fractions.Regression analyses revealed that both the free Cu2+ions in the soil solution and the humic acid-complexed Cu fraction in the solid phase were strongly related with soil microbial parameters.     

在法国前铅和锌冶炼厂附近的城市土壤重金属的污染、分离和利用

smelters in Northern France were studied by analysing the chemical forms of these metals and evaluating their phytoavailability. These metals were determined using flame or electrothermal absorption atomic spectrometry （FAAS or ETAAS）, depending on their concentration levels. After optimisation of the ETAAS method, characteristic mass of In in water and aqua regia were 9.9 and 18 pg, respectively, showing the high sensitivity of the analytical Soil contamination by metals from anthropogenic activities （e.g., mining and smelting） is a major concern for the environment and human health. Environmental availability of cadmium （Cd）, lead （Pb）, zinc （Zn）, copper （Cu）, and indium （In） in 27 urban soils located around two former Pb and Zn smelters in Northern France were studied by analysing the chemical forms of these metals and evaluating their phytoavailability. These metals were determined using flame or electrothermal absorption atomic spectrometry （FAAS or ETAAS）, depending on their concentration levels. After optimisation of the ETAAS method, characteristic mass of In in water and aqua regia were 9.9 and 18 pg, respectively, showing the high sensitivity of the analytical procedure. Metal partitioning was conducted using a four-step sequential extraction procedure. The results showed that Cd and Zn were mainly in the acid-extractable and reducible forms in the urban soils studied. In contrast, Pb and In were largely in the reducible fraction. However, in some samples, the amount of In extracted in the residual or exchangeable fraction was higher than that in the reducible fraction. Copper was mainly found in the reducible and residual fractions. A pot experiment was conducted in a glasshouse with seven soils （six contaminated and one uncontaminated） and two plant species, ryegrass and lettuce. The results showed transfer of metals from the contaminated soils to the shoots of ryegrass and the edible part of lettuce. The metal bioconcentration factor was in the order of Cd Cu > In > Zn Pb for lettuce leaves, whereas for ryegrass shoots, three orders were found, Cd > Zn > Cu In > Pb, Cd ≥ In > Zn > Cu Pb, and Zn > Cd > Cu > In > Pb, depending on the physico-chemical properties of the soils, such as pH, cation exchange capacity, carbonates, and organic matter. It was established that the metal toxicity was related to the contamination levels and the physico-chemical properties, including pH, organic matter, and in a lesser extent, Ca, Mg, and phosphorus contents, of the soils. However, it was shown that lettuce could grow on soils having high Cd and CaCO₃ contents. Cadmium was one of the most available metals while Pb was always the least available in the soils studied.     

分光光度法测定有机肥料中铜、铁、锌、锰含量

探索用分光光度法测定有机肥料中的微量元素铜(Cu)、铁(Fe)、锌(Zn)、锰(Mn)含量,并研究了显色反应的酸度条件、干扰因素及消除方法。该检测方法简单快速,可应用于有机肥生产企业中微量元素铜、铁、锌、锰的测定。