施磷对苦麦菜生长及土壤磷素淋失的影响

利用网室土柱模拟试验, 研究了不同磷用量[0、0.05 g·kg^-1(土)、0.10 g·kg^-1(土)、0.20 g·kg^-1(土)]对苦麦菜产量、磷素吸收和利用及土壤磷淋失的影响。结果表明, 施磷显著增加苦麦菜产量、促进植株对磷的吸收。苦麦菜产量在低磷水平[0.05 g·kg^-1(土)]时最高, 为每个土柱186.29 g。随磷用量增加, 苦麦菜产量和磷肥利用率明显降低, 植株吸磷量无明显变化。施磷显著增加土壤磷淋失量, 且随磷用量增加, 不同形态磷淋失量均显著增加。同一磷处理颗粒磷淋失量高于溶解态磷。不同磷用量条件下土壤各形态磷的淋失率均低于0.1%。低量施磷条件下溶解态磷在施磷后第10 d 出现第1 次淋失高峰; 中量和高量施磷条件下溶解态磷在施磷后第10 d 和第40 d 分别出现2 次淋失高峰。土壤总磷和颗粒磷淋失高峰期在施磷后第40~50 d 出现。施肥后第60 d, 土壤总磷、溶解态磷和颗粒磷淋失浓度均明显降低。综合考虑苦麦菜产量、磷素吸收和利用及土壤磷淋失量等因素, 苦麦菜以0.05 g·kg^-1(土)的施磷量为佳。     

Effect of cadmium,copper, and zinc on the growth of blackgram

Blackgram (Vigna mungo, L.) growth was measured in a glasshouse earthen‐pot experiment. Cadmium (Cd), copper (Cu), and zinc (Zn) were applied in different concentrations to the soil. The plant and soil samples were analysed 45 days after sowing using ICP‐AES. The dry matter yield of tissue showed highly significant reduction (at the 1% level) for Cd and Cu, and nonsignificant variation for Zn. This shows that phytotoxicity for Cd and Cu was greater than that for Zn. Further, the observed higher correlation coefficients suggest that the concentration of the elements in tissue is linearly related to that applied to the soil.     

磷对水培生菜生长及矿质元素动态吸收的影响

磷是植物所需大量元素之一,对植物的生长有重要影响。传统的土培条件下磷肥难以移动,导致施磷量和植物可利用磷量差别较大;而水培条件下磷肥均匀存在于营养液中,不仅有利于植物吸收利用,也为定量精确地研究磷对植物的影响提供了便利。为探明磷素对生菜生长、品质以及矿质元素吸收的影响,试验设置5个磷水平(Na H2PO4),分别为0.2 mmol·L?1、0.4 mmol·L?1、0.6 mmol·L?1、0.8 mmol·L?1、1.0 mmol·L?1,对不同磷水平下生菜生长、产量、品质及营养液矿质元素动态吸收量进行分析。结果表明当磷水平为0.4 mmol·L?1时生菜的综合品质最好;当磷水平为0.6 mmol·L?1时,生菜产量最大,且全生育期对氮、磷、钾、钙、镁的吸收总量达到最大,为691.26 mg·株?1,对氮、磷、钾、钙、镁的吸收比例为1∶0.20∶1.34∶0.80∶0.24。不同磷素水平下,生菜对氮吸收量差异不大;随磷素水平的提高,生菜对磷的吸收量不断增大,即对磷有奢侈吸收的趋势;对氮和磷的吸收主要集中在定植后的第20~30 d,此阶段平均吸收量分别占全生育期总吸收量的79.86%和59.25%;对钾的吸收量随时间呈不断地加大趋势,在收获前10 d达到最大值,此阶段平均吸收量占全生育期总吸收量的47.68%;对钙、镁的吸收在整个生育期变化不明显,定植后10~30 d对钙的吸收量较大;收获前30 d对镁的吸收量较大。全生育期内,生菜对钾的吸收比例最大,其次是氮、钙;高磷条件下磷的吸收比例大于镁,低磷条件下对镁的需求比例高于磷;生菜对磷的利用效率随磷水平的增加不断减小,较低磷素水平有利于提高矿质元素的利用效率。     

Arbuscular mycorrhizas modify tomato responses to soil zinc and phosphorus addition

Arbuscular mycorrhizas (AM) play an important role in plant P and Zn nutrition; however, relatively few studies have directly investigated the interactive effects of these nutrients on plants. Therefore, we undertook a glasshouse experiment to study the effects of Zn and P on AM formation and functioning. A mycorrhiza defective tomato mutant (rmc) and its mycorrhizal wild-type progenitor (76R) were used in this experiment. Plants were grown in soil amended with five Zn concentrations, ranging from deficient to toxic, and two levels of P addition. The addition of Zn and P to the soil over a range of concentrations had profound effects on plant growth and nutrition and mycorrhizal colonization. Mycorrhizal benefits were the greatest when plants were grown under low soil P and Zn. Furthermore, the effect of soil Zn supply on plant growth, nutrition, and AM colonization was strongly influenced by the concentration of P in the soil. Thus, studies of AM and Zn (or other nutrients of interest) should take into account the impact of soil P concentration on the role of AM in plant Zn acquisition, under both deficient and toxic soil Zn concentrations.     

The influence of soil properties,total copper,iron, manganese,and zinc on the yield of oat,carrot, onion and lettuce

Abstract

As part of a series of studies for evolving useful soil tests for Cu, Fe, Mn and Zn in cultivated organic soils, 55 such soils from eastern Canada were used in a greenhouse study. Oat, carrot, onion, and all three followed by lettuce were grown in a greenhouse in 2 L pots containing 1.8 L of soil. The moisture, fertilization and temperature conditions provided were known to be non‐Hmiting. And yet, yields of crops, on per kg soil basis, generally correlated negatively with certain soil properties. The more decomposed and denser soils tended to be less productive, even though more soil, but not significantly less water, was accessible to the roots in such soils than in the case of less decomposed, more open soils. In contrast, crop yield per unit soil volume (1.8 L) basis showed a negative effect of water holding capacity on yield of oat, and positive effect of pH on carrot yield. No other correlations were significant. The results thus corroborated the practice of basing soil tests and fertilizer reconmendations on volume rather than weight of organic soils; indicated that the quality of organic soils, in terms of ability to store and cycle water, oxygen and nutrients, declines with length of cultivation, even before nutritional and water management problems arise, probably due to poor soil aeration; and suggested that the effect of soil quality on potential productivity be examined to derive factors that would help refine fertilizer recommendations.     

氮、磷、锌肥对纤维亚麻产量的效应

采用“311-B”最优回归设计,通过亚麻田间试验取得的产量数据,建立亚麻N、P、Zn肥的肥料效应函数,解析了各因素对亚麻产量的效应,提出高产纤维亚麻的施肥配方。     

Effect of excess lead,cadmium, copper,and zinc on water relations in sunflower

The effect of excess concentrations of lead (Pb), cadmium (Cd), copper (Cu), and zinc (Zn) on water relations in young sunflower (Helianthus annuus L.) plants was studied in water culture under greenhouse conditions. The accumulation of the heavy metals was more intensive in the root than in the shoot. The rates of heavy metal accumulation in root were arranged in the following decreasing order: Cu, Cd, Zn, and Pb. Their transport into the above‐ground parts followed the order: Zn, Cu, Pb, and Cd. Transpiration and relative water content were significantly decreased by excess concentrations of the heavy metals. The number of stomata per unit leaf area was increased while the size of the stomata was decreased. The concentration of free proline significantly increased in the leaves of intact plants as well as in leaf discs incubated in the presence of heavy metals. The concentration of soluble proteins decreased as well, particularly when plants were exposed to high concentrations of the heavy metals. It was concluded that excess concentrations of the heavy metals significantly affected plant water status, causing water deficit and subsequent changes in the plants. The most intensive effect on the plants was exerted by Cd, less intensive by Cu and Zn and the least intensive by Pb.     

Effect of attendant anions on the adsorption of zinc, copper, and lead by chernozem

The adsorption of Cu, Zn, and Pb from acetate solutions is accompanied by higher values of the affinity constants compared to the adsorption of the same cations from nitrate solutions. The observed differences are due to the formation of stable charged complexes of acetate ions with heavy metal cations, whose binding strength with the surface of soil particles is higher than that of free ions, and also due to the possible precipitation of poorly soluble metal compounds in a calcareous ordinary chernozem.     

Effect of organic acids on the adsorption of copper,lead, and zinc by goethite

The adsorption of Cu, Pb, and Zn by synthetic goethite was studied in the absence and presence of oxalic, citric, and glutamic acids at different pH values. It was shown that, in the absence of an acid, the content of adsorbed metals increased with the increasing pH. The content of adsorbed cations at constant pH values decreased in the sequence: Cu > Pb > Zn. The simultaneous addition of metal cations and organic acids to the goethite suspension increased the content of the adsorbed elements. The oxalic and citric acids had similar effects on the adsorption of copper and lead in the studied pH range. The metal: acid concentration ratios significantly affected the adsorption of the heavy metals by goethite. An increase in the metal adsorption was observed to a certain metal: acid ratio, which was followed by a gradual decrease. The adsorption of the metals by goethite also depended on the properties of the metal cations and the organic ligands. The observed tendencies were attributed to the complexation of heavy metals with organic acid anions and the simultaneous sorption of acids at positively charged sites on the goethite surface with the formation of mineral-organic compounds, which significantly modified the surface properties of the mineral. The study of the effect of increasing lead concentrations in the solution on the copper adsorption by goethite in the absence, in the presence, and at the addition of an oxalic acid solution to the goethite suspension one hour before the beginning of the experiment showed that lead decreased the adsorption of copper in all the treatments. The possible mechanisms of the processes occurring in the system were considered.     

长期施肥对黑土磷和锌形态转化的影响

【目的】东北黑土地为我国重要粮食生产基地高肥力的黑土仍需施用磷肥以保障粮食高产。探讨长期施肥对土壤磷和锌形态转化机制,为确保黑土区粮食和环境安全提供理论依据。【方法】本研究以设在典型黑土区13年的长期施肥定位试验为研究对象,设不施肥(CK)、施氮磷钾肥(NPK)、施氮磷钾加不同量有机肥(NPK+OM_1、NPK+OM_2、NPK+OM_3)共5个处理分析土壤不同形态磷和锌含量。【结果】长期施化肥对土壤有机磷含量影响不显著但土壤无机磷含量显著增加;长期不施肥黑土有效磷含量为32.6 mg/kg,长期施化肥加有机肥可显著增加土壤有效磷含量;连续13年施用磷肥,土壤中的磷每年平均累积16 kg/hm~2,其主要以铝磷(A1-P)和铁磷(Fe-P)的形态在土壤中储存,其中约20%仍为有效磷;而磷肥加有机肥的3个处理,连续施用13年后有机磷含量增加了47.2~67.9 mg/kg无机磷含量增加253.4~410.6 mg/kg,土壤全磷平均分别以每年49.4(NPK+OM_1)、64.2(NPK+OM_2)、70.4(NPK+OM_3)kg/hm~2的量累积在土壤中,其中15%~21%仍为有效磷主要以有效性较高的二钙磷(Ca_2-P)、八钙磷(Ca_8-P)、Al-P、Fe-P存在于土壤中,只有10%~21%的磷以有机磷的形态累积在土壤中,并且这个比例随有机肥施用量的增加而降低。黑土长期不施肥土壤有效锌(DTPA-Zn)含量可达1.96mg/kg,长期施化肥、化肥加有机肥均可显著增加土壤DTPA-Zn含量;长期施化肥使黑土酸化,改变了土壤锌形态增加了土壤交换态锌和无定型铁氧化物结合态锌的含量,化肥加有机肥显著增加了除矿物态锌以外的其他各形态锌的含量其中55%~88%以无定型铁氧化物结合态锌储存在土壤中。通径分析结果显示,Ca_2-P对DTPA--Zn影响最大,Ca_8-P、Al-P、Fe-P通过Ca2-P间接影响DTPA-Zn含量。【结论】长期施入黑土的磷主要以有效性较高的无机态磷储存在土壤中,锌主要以无定型铁氧化物结合态储存在土壤中。黑土中磷与锌未表现出拮抗作用且有效性高的Ca_2-P对DTPA-Zn含量的影响最大且二者呈正相关关系。     

Fluorine and copper accumulation in lettuce grown on fluoride and copper contaminated soils

ABSTRACT

Presence of copper (Cu) and fluorine (F) in soils pose a risk of food web contamination when crops are grown on such soils. Greenhouse experiments involving 34 soil samples were carried out to explore the uptake of F and Cu by lettuce (Lactuca sativa L.). Each soil sample was divided into two parts. One set was irrigated with tap-water and another set was irrigated with F-contaminated water. Lettuce plants were grown for 60 days then harvested. Data were analyzed using stepwise regression analysis, t- or F-tests. Soils contained elevated concentrations of F and low to high concentrations of Cu. Soluble fractions of F were higher than reported values from other studies. It was observed that the soluble F or Cu contents in F-contaminated irrigated soils were significantly higher than the F or Cu contents in tap-water irrigated soils. Concentrations of F in lettuce were higher than normal F concentrations in plants. Soil EC was negatively related with the concentration of Cu in lettuce. A negative relationship occurred between the concentrations of F and Cu in the lettuce plants, signifying that the two pollutants have antagonistic relationships. The lettuce irrigated with F^? contaminated water, accumulated higher concentrations of F than the lettuce irrigated with tap water, indicating that the F-contaminated water irrigated lettuce was more contaminated than the tap-water irrigated lettuce.     

水磷互作对潮土玉米苗期生长及磷素积累的影响

利用温室盆栽试验研究了水磷互作对潮土玉米苗期生长及磷素积累的影响。结果表明,水、磷能显著影响玉米株高与叶面积状况。水分胁迫条件下,适度施磷处理比对照玉米株高和叶面积分别增加69.7%和33.6%;而适水条件下分别增加38.3%和48.0%。适度施磷条件下,水分胁迫促进了玉米根系发育,根干重与根冠比均高于适水处理。水磷配合能提高了玉米干物质积累量,表现出显著正交互效应。适度施磷范围内,适水处理能显著提高植株体磷素吸收积累总量,但对植株磷含量影响不大;适水处理下,过量施磷会导致植株对磷素奢侈吸收,而在水分胁迫下反而降低对磷素的吸收积累。水磷适度配合表现出较好的耦合效果,达到“以水促磷”与“以磷促水”的目的。     

Effect of phosphorus on zinc toxicity in tea pollen tube growth

Although zinc (Zn) is an essential element for the growth of higher plants, excess supply may lead to growth inhibition. Symptoms of Zn toxicity are characterized by a reduction in root growth and leaf expansion followed by chlorosis (Mengel and Kirkby 1987), especially root elongation is severely inhibited (Godbold et al. 1983). Due to the increase of input of Zn to farmland by the application of sewage sludge or large amounts of Zn-containing pig manure, Zn toxicity may become an important problem in certain regions (Ruano et al. 1987). In addition, Zn toxicity is also a problem in some acidic soils (Takahashi et al. 1980).

Increasing soil pH by liming is the most effective procedure for decreasing both Zn content and Zn toxicity in plants (White et al. 1979), because Zn solubility decreases 100 times for each unit increase in pH (Neue and Lantin 1994). As an alternative approach, application of large amounts of phosphorus (P) fertilizer was employed to detoxify Zn (Takahashi et al. 1980). However, the mechanisms responsible for the detoxification of the excess Zn by P is remained to be elucidated.

Interactions between Zn and P, which may occur in the rhizosphere and in the uptake and translocation processes, are complex. To separate these factors, in the present study, pollen tubes of tea (Camellia sinensis L.) were used as a model, and the efrect of P on pollen tube growth under Zn toxicity was studied.     

外源磷与AMF对间作玉米种植红壤无机磷形态的影响

通过三室隔网分室盆栽模拟试验,研究了分室不同磷(P)源[无机磷(磷酸二氢钾)和有机磷(大豆卵磷脂),P添加量均为50 mg·kg-1]添加和根室接种不同丛枝菌根真菌(AMF)[Glomus mosseae(GM)、Glomus etunicatum(GE)]对间作玉米种植红壤无机磷形态的影响。结果表明:无论接种与否,间作处理使根室土壤有效磷含量显著降低,说明间作能够促进玉米植株对土壤有效磷的吸收,且有效磷的耗竭从根际土壤开始。除OP50-单作玉米处理的Org-P外,接种AMF均一定程度增加了各形态无机磷含量。此外,根室土壤有效磷的主要组分为Ca2-P、Al-P和Org-P,其中Org-P与土壤有效磷有着极显著的负相关关系。     

Effect of aluminum, zinc, copper, and lead on the acid-base properties of water extracts from soils

The potentiometric titration of water extracts from the upper horizons of taiga-zone soils by salt solutions of heavy metals (Pb, Cu, and Zn) showed that their addition is an additional source of the extract acidity because of the involvement of the metal ions in complexation with water-soluble organic substances (WSOSs). At the addition of 0.01 M water solutions of Al(NO₃)₃ to water extracts from soils, Al³⁺ ions are also involved in complexes with WSOSs, which is accompanied by stronger acidification of the extracts from the upper horizon of soddy soils (with a near-neutral reaction) than from the litter of bog-podzolic soil (with a strongly acid reaction). The effect of the Al³⁺ hydrolysis on the acidity of the extracts is insignificantly low in both cases. A quantitative relationship was revealed between the release of protons and the ratio of free Cu²⁺ ions to those complexed with WSOSs at the titration of water extracts from soils by a solution of copper salt.     

Effect of the main soil components on the sorption of copper,zinc, and lead by urban soils

The sorption of copper, zinc, and lead by two urban soils with different levels of contamination was studied. Changes in the sorption capacity and fixation strength of the metals were revealed after the destruction of the main components playing the important role in the fixation of metals by the soil.     

Interaction of soil compaction, phosphorus and zinc on clover growth and accumulation of phosphorus

Soil compaction generally reduces crop performance because of degraded soil physical and biological properties, and possibly inappropriate soil nutritional status. The effects of varying compaction, and phosphorus (P) and zinc (Zn) supplies on the growth of Berseem or Egyptian clover (Trifolium alexandrimum), and accumulation of P and Zn in shoots and roots were investigated in a pot experiment using a surface layer of a Typic Torrifluvent (USDA), Calcaric Fluvisols (FAO) soil. Plants were treated with three soil compaction levels, three rates of P and three rates of Zn in a factorial combination. Phosphorus accumulation in shoots did not change up to bulk densities of 1.65 Mg m⁻³ and declined at bulk density of 1.80 Mg m⁻³. Increasing the levels of Zn and P resulted in a significant increase in shoot dry mass (from 0.3 to 0.8 g pot⁻¹), and root length (from 11.4 to 32.5 m pot⁻¹). Shoot and root growth were reduced by soil compaction particularly at low P and Zn application rates. Shoot dry mass was reduced from 0.8 to 0.3 g pot⁻¹, and root length from 43 to 5 m pot⁻¹ at bulk densities of 1.4 and 1.8 Mg m⁻³, respectively. However, the accumulation of P (from 0.06 to 0.15 g kg⁻¹) and Zn per unit length of roots (from 0.8 to 1.8 μg pot⁻¹) increased as soil compaction increased. As the Zn supply increased, Zn accumulation per unit length of roots, and total Zn accumulation increased. Severe compaction reduced P and Zn accumulation in shoots and also decreased shoot dry mass, and root length compared to lower soil compaction levels. The present study suggests that Zn and P supply can moderate the adverse effect of soil compaction on clover performance.     

Effect of iron plaque on roots of rice on growth of plants in excess zinc and accumulation of phosphorus in plants in excess copper or nickel

Iron (Fe) plaque on roots of rice was found to lessen the toxic effects of zinc (Zn). With excess Zn, plants with Fe plaque had significantly greater dry mass of roots and foliage than plants without plaque. In the excess of Zn, plants with Fe plaque had higher concentrations of Fe but lower Zn than plants without plaque, although the differences were not significant. In the excess of copper (Cu) or nickel (Ni), plants with Fe plaque had significantly lower concentration of phosphorus (P) in leaves than plants without plaque. It is suggested that the low concentration of P in leaves of plants with plaque will increase the concentration of “active iron”; inside leaves, and therefore, increase their tolerance against heavy metal toxicity.     

Effect of litters on the mobility of zinc, copper, manganese, and iron in the upper horizons of podzolic soils

The concentrations of water-soluble Cu, Zn, Mn, and Fe in the litters of the peaty-podzolic-gleyic and pale-podzolic soils of the Central Forest State Biosphere Reserve are inversely proportional to the pH and directly proportional to the total titratable acidity of the extracts and the content of the water-soluble organic matter (WSOM). During the interaction of the litter solutions with the mineral soil horizons, the content of metals in the solutions can vary depending on the pH, the WSOM concentration in the input solutions, the WSOM amphiphility, and the nature of the metal. The amount of water-soluble Mn, Cu, and Zn in the Eih horizon of peaty-podzolic-gleyic soils is directly proportional to the content of WSOM and inversely proportional to the pH of the litter solutions; the Fe concentration increases parallel to both parameters.     

Effect of nitrogen and phosphorus on zinc nutrition of corn in a calcareous soil

Different factors affect zinc (Zn) nutrition of plants, among which pH and phosphorus (P) have been studied widely but nitrogen (N) has not received much attention. The present experiment was designed to study the effect of N and P on growth and Zn nutrition of corn (Zea mays L.) in a highly calcareous soil of Iran. The experiment was a 3x3x2 factorial in randomized complete blocks with three replications which was conducted in greenhouse for eight weeks. Treatments consisted of three levels of N (0,75, and 150 mg/kg), three levels of P (0, 50, and 100 mg/kg), and two levels of Zn (0 and 20 mg/kg). Application of N increased dry matter (DM), N concentration and uptake, Zn concentration and uptake, and N: P and N: Zn ratios of plant tops; but it decreased P concentration and uptake and P: Zn ratio. Application of P increased DM, P concentration and uptake, N uptake, and P: Zn and N: Zn ratios; but it decreased N and Zn concentrations and N: P ratio. Dry matter and Zn concentration and uptake increased but P: Zn and N: Zn ratios decreased following the application of Zn. Multiple regression equations obtained showed the influence of N application on increasing Zn concentration and uptake and lowering the P: Zn ratio of plant tops. It was concluded that N application improves Zn nutrition of corn in highly calcareous soils by increasing plant Zn concentration and uptake and decreasing P concentration. This lowers the P: Zn ratio of plant tops to a more optimum range for plant growth.