土壤中氮磷钾肥转化中的交互作用: Ⅰ.土壤pH的动态变化

Dynamic changes of soil pH as influenced by ammonium sulfate (AS), monocalcium phosphate (MCP),potassium chloride (KCl) and their interaction in soils were evaluated in incubation experiments. Applyingthese fertilizers significantly reduced soil pH values in all cases and followed sequences of AS ＞ MCP ＞KCl, MCP ＞ KCl ＞ AS and KCl ＞ AS ＞ MCP for the paddy, calcareous and red soils, respectively. TheAS-induced reduction of pH in the three soils followed the sequence of red soil ＞ paddy soil ＞ calcareous soil,while in MCP and KCl systems the reduction of pH followed the sequences of calcareous soil ＞ paddy soil ＞red soil and red soil ＞ calcareous soil ＞ paddy soil, respectively. The interactions of the NPK fertilizers on pHwere significant. MCP plus KCl or MCP plus AS reduced pH values more than the fertilizers applied solelyin the paddy soil, but AS partly counteracted the effect of MCP on pH in the 1 d sample of the calcareoussoil. The effect of MCP on pH was trivial when MCP was applied in combination with KCl or AS in the redsoil. When applied in combination with AS, KCl did not affect soil pH initially, but suppressed the reductionof pH at the later incubation stage, which was related to inhibition of nitrification by KCl in the soils.     

不同土壤水分状况下遮蔽对棉花叶片气体交换的影响

An incubation experiment was carried out in laboratory to study the effect of temperature,moisture,phosphorus,organic matter,cropping and previous elemental sulfur application on elemental sulfur oxidation in four selected soils,fluvo-aquic soil,black soil,yellow-brown soil and red soil,In all the soils tested,sulfur oxidation rate was influenced by temperature and the temperature coefficient(Q10) values at the range from 10 to 30℃ were 4.41,,6.19 and 3.71 for the four soils,respectively.The rate of sulfur oxidation was parabolically related to soil water content.The optimum moisture content for the maximum oxiation rate was different among soils,Phosphorus increased the oxidation rate of elemental sulfur by 57.7%,33.1%,21.7% and 26.4% for the above four soils,respectively,compared with the control (no phosphorus applied).Organic material of corn straw which was gound and passed through a 0.5-mm sieve also increased th oxidation rate of elemental sulfur in the four soils by 59.8%,7.8%,39.2% and 540.4%,respectively.Elemental sulfur which was applied previously to soils significantly enhanced the oxidation of elemental sulfur subsequently added and increased sulfur-oxidizing populations such as autotrophic elemental sulfur oxidizers with pH optimum 6.8,autotrophic thiosufate oxidizers with pH optimum 6.8,heterotrophic thiosulfate oxidizers and heterotrophic sulfate producers.Cropping had little effect on elemental sulfur-oxidizing potentiality of soils.     

农田土壤中氮同位素分级与硝化能力的关系研究

A laboratory-based aerobic incubation was conducted to investigate nitrogen(N) isotopic fractionation related to nitrification in five agricultural soils after application of ammonium sulfate((NH4)2SO4). The soil samples were collected from a subtropical barren land soil derived from granite(RGB),three subtropical upland soils derived from granite(RQU),Quaternary red earth(RGU),Quaternary Xiashu loess(YQU) and a temperate upland soil generated from alluvial deposit(FAU). The five soils varied in nitrification potential,being in the order of FAU YQU RGU RQU RGB. Significant N isotopic fractionation accompanied nitrification of NH+4. δ15N values of NH+4 increased with enhanced nitrification over time in the four upland soils with NH+4 addition,while those of NO-3 decreased consistently to the minimum and thereafter increased. δ15N values of NH+4 showed a significantly negative linear relationship with NH+4-N concentration,but a positive linear relationship with NO-3-N concentration. The apparent isotopic fractionation factor calculated based on the loss of NH+4 was 1.036 for RQU,1.022 for RGU,1.016 for YQU,and 1.020 for FAU,respectively. Zero- and first-order reaction kinetics seemed to have their limitations in describing the nitrification process affected by NH+4 input in the studied soils. In contrast,N kinetic isotope fractionation was closely related to the nitrifying activity,and might serve as an alternative tool for estimating the nitrification capacity of agricultural soils.     

华中南部某些土壤针铁矿的形态

The morphologies of goethites in latosol, red soils, yellow-brown soil and the paddy soils developed from red soils were studied in comparison with the morphology of synthetic goethite by means of the X-ray diffraction, transmission electron microscopy and energy dispersive X-ray analysis. The synthetic goethite displayed acicular particles elongated in the c-direction. The goethites in the latosol, red soils and yellow-brown soil were platy particles stretched in two directions or isodimensional particles, and those in the paddy soils from red soils were acicular, short columnar, platy or isodimensional particles. Various morphologies of the goethites probably suggested their different dominant crystal faces, surface charge distribution and surface adsorption characteristics.     

重金属迁移与土壤性质的关系

Cu, Zn, Pb and Hg runoff from yellow limestone soil and purple soils and the relationships between the mobility of the heavy metals and the soil characteristics were studied in laboratory using a rainfall simulator. The results showed that the concentrations of soluble Zn in surface runoff were significantly negatively correlated with the contents of < 0.002 mm particles and CEC of the soils, indicating that Zn was mostly adsorbed by clays in the soils. The contents of Cu and Hg in surface runoff were positively related to their contents in the soils. The amounts of Cu, Zn, Pb and Hg removed by surface runoff were influenced by the amounts of soil and water losses and their contents in the soils, and were closely related to the contents of soil particles 1~0.02 mm in size.     

青藏高原土壤中15N和全氮形态及其与土壤环境因子间的关系

The patterns of soil nitrogen(N) isotope composition at large spatial and temporal scales and their relationships to environmental factors illustrate N cycle and sources of N,and are integrative indicators of the terrestrial N cycle and its response to global change. The objectives of this study were:i) to investigate the patterns of soil N content and natural abundance of 15N(δ15N) values in different ecosystem types and soil profiles on the Qinghai-Tibetan Plateau; ii) to examine the effects of climatic factors and soil characteristics on the patterns of soil N content and soil δ15N values; and iii) to test the relationship between soil δ15N values and soil C/N ratios across ecosystems and soil profiles. Soil profiles were sampled at 51 sites along two transects 1 875 km in length and 200 km apart and distributed in forest,meadow and steppe on the Qinghai-Tibetan Plateau. Each site was sampled every 10 cm from a soil depth of 0 to 40 cm and each sample was analyzed for soil N content and δ15N values. Our results indicated that soil N and δ15N values(0–40 cm) in meadows were much higher than in desert steppe. Soil N decreased with soil depth for each ecosystem,while variations of soil δ15N values along soil profiles were not statistically significant among most ecosystems but for mountain meadow,lowland meadow,and temperate steppe where soil δ15N values tended to increase with soil depth. The parabolic relationship between soil δ15N values and mean annual precipitation indicated that soil δ15N values increased with increasing precipitation in desert steppe up to 500 mm,and then decreased with increasing precipitation across all other ecosystems. Moreover,the parabolic relationship between δ15N values and mean annual temperature existed in all individual ecosystem types. Soil N and δ15N values(0–40 cm) increased with an increase in soil silt and clay contents. Furthermore,a threshold of C/N ratio of about 11 divided the parabolic relationship between soil δ15N values and soil C/N ratios into positive(C/N 11) and negative(C/N 11) parts,which was valid across all ecosystems and soil profiles. The large explanatory power of soil C/N ratios for soil δ15N values suggested that C and N concentrations,being strongly controlled by precipitation and temperature,were the primary factors determining patterns of soil δ15N on the Qinghai-Tibetan Plateau.     

腐殖酸对矿物结合汞活性的影响研究: Ⅲ.对酸性淋溶条件下矿物结合汞的淋洗与迁移的影响

Made teas and typical tea-grown soils in sichuan and chongqing were collected to investigate soil nutrients,related soil properties and tea quality.The tea-grown soils in Sichuan and Chongqing are distributed mainly in mountainous areas.The high annual precipitation(over 1100mm),precipitous soil plopes,low cohesion among soil particles and high soil porosity suggested that intensive erosion and leaching might occur in these soils,Morever,they were very acidic and poor in mineral nutrients such as N,P,K,Ca and Mg except S.The average content of total S was 20.40g kg^-1,much higher than that of organic matter in these soils,revealing that S in the tea-grown soils existed mainly in inorganic forms and very little in organic forms.Water-extractable S accounted for only a small amount of total S, which showed that ost parts of sulfur in these soils were insoluble in water,K and S varied greatly in made teas,The concentrations of N and P,however,varied little in these teas even though they differentiated significantly in the tea-grown soils.The high concentration of nitrogen in made teas could result in the high free amino acids and low polyphenol of teas,Significantly positive correlation was established between potassium and polyphenol in made teas.Teas with high ratio of phenol to free amino acids were usually good taste and appearance.     

中国青海湖地区草地蝗虫与土壤的关系

A growth chamber study was conducted to determine the relationships between the supply of soil available nitrogen （N） and sulfur （S） and canola （Brassica napus） and wheat （Triticum aestivum L. ‘Biggar＇） N and S uptake and yield in three Western Canadian soils. The suitability of one-hour burial with an anion exchange membrane （AEM） was assessed for its utility as a quick test of the available N：S balance in the soil. Canola and wheat were grown on a Luvisolic soil low in available S and on Brown and Black Chernozemic soils low in both available N and S, with different rates and combinations of N and S fertilizers applied. AEM burial was used to assess soil available nitrate and sulfate supply rates after fertilization. Dry matter yield and N and S concentrations in plant tissues were determined after 6 weeks of growth. The soil available N：S ratio determined by AEM burial closely reflected the relative supplies of available N and S as revealed in the N：S ratios of plant tissue dry matter. The highest yields were achieved where the available N：S ratio in soil and plant tissue ranged from 5 to 13. Thus, a one-hour burial of an AEM probe in the field may be a useful tool to quickly test if a balanced N and S supply is present in the soil for optimum crop yield.     

中国下蜀黄土发育的土壤表层及典型剖面的硫状况

Studies were conducted to examine factors which might influence the status and distribution of S in some surface horizons and typical profiles of soils derived from Xiashu loess on the upper slope (US), middle slope (MS) and lower slope (LS) of Nanjing-Zhenjiang-Yangzhou hilly zone. The total S contents varied from 70.30 to 350.21 mg/kg, and the average for all surface soils was 218.3 mg/kg. The average S contents in the profiles followed the sequence: USo) and the ratio of amorphous iron oxide to free iron oxide (Fe_o/Fe_a), but no significant relationship was found between total S and the ratio of free iron oxide to total iron (Fe_d/Fe_t). Inorganic sulphate in paddy soils (MS and LS) was nearly higher in surface soil than in subsurface soil and subsoil, it, however, remained relatively unchanged with increasing depth for the original soil profile (US). The average organic S accounted for 94% of the total S in the surface soils, but the percentage decreased with depth in the profiles. Like the total S, the organic and inorganic S contents were highly significantly correlated with organic matter, total N, Fe_o and Fe_o/Fe_d ratio, but they were insignificantly related to Fe_d/Fe_t ratio. The C/S and N/S ratios in this study were somewhat lower than the results reported by others. The C/N/S ratios varied considerably within the same profile and among different soils but they fell within the range of values reported worldwide.     

Alberta油砂地区在两种水文流域森林土壤酸化敏感性研究

Input of large amounts of N and S compounds into forest ecosystems through atmospheric deposition is a significant risk for soil acidification in the oil sands region of Alberta. We evaluated the sensitivity of forest soils to acidification in two watersheds （Lake 287 and Lake 185） with contrasting hydrological regimes as a part of a larger project assessing the role of N and S cycling in soil acidification in forest ecosystems. Fifty six forest soil samples were collected from the two watersheds by horizon from 10 monitoring plots dominated by either jack pine （Pinus banksiana） or aspen （Populus tremuloides）. Soils in the two watersheds were extremely to moderately acidic with pH （CaCl2） ranging from 2.83 to 4.91. Soil acid-base chemistry variables such as pH, base saturation, Al saturation, and acid-buffering capacity measured using the acetic acid equilibrium procedure indicated that soils in Lake 287 were more acidified than those in Lake 185. Acid-buffering capacity decreased in the order of forest floor 〉 subsurface mineral soil 〉 surface mineral soil. The most dramatic differences in percent Ca and Al saturations between the two watersheds were found in the surface mineral soil horizon. Percent Ca and Al saturation in the surface mineral soil in Lake 287 were 15% and 70%, respectively; the percent Ca saturation value fell within a critical range proposed in the literature that indicates soil acidification. Our results suggest that the soils in the two watersheds have low acid buffering capacity and would be sensitive to increased acidic deposition in the region.     

FeSO_4-ZnSO_4-H_2O水盐体系相图及其应用

采用等温溶解平衡法研究了ZnSO4-FeSO4-H2O体系平衡关系,以Zn2+、Fe2+浓度为坐标轴,在直角坐标系中制出了0℃、10℃和25℃时ZnSO4-FeSO4-H2O体系相图,在相图中单相区和c(Fe2+)+c(Zn2+)=100 g/L直线上方的重合区域就是Zn-Fe微量元素水溶肥料的配方区。多温相图分析及实验表明:根据10℃时ZnSO4-FeSO4-H2O相图配方区制备出来的Zn-Fe微量元素水溶肥料具有良好的储存性能。     

在实验酸性硫酸盐条件和酸性硫酸盐土壤上可溶性铝的控制

The controls of soluble Al concentration were examined in three situations of acid sulfate conditions:1) experimental acid sulfate conditions by addition of varying amounts of Al(OH)3(gibbsite) into a sequence of H2SO4 solutions;2)experimental acid sulfate conditions by addition of the same sequence of H2SO4 solutions into two non-cid sulfacte soil samples with known amounts of acid oxalate extractable Al; and 3) actual acid sulfate soil conditions.The experiment using gibbsite as an Al-bearing mineral showed that increase in the concentration of H2SO4 solution increased the soluble Al concentration,accompanied by a decrease i the solution pH, Increasing amount of gibbsite added to the H2SO4 solutions also increased soluble Al concentration,but resulted in an increase in solution pH.Within the H2SO4 concentration range of 0.0005-0.5mol L^-1 and the Al(OH)3 range of 0.01-0.5g(in 25 mL of H2SO4 solutions),the input of H2SO4 had the major control on soluble Al Concentration and pH .The availability of Al(OH)3，however,was responsible for the spread fo the various sample points,with a tendency that the samples containing more gibbsite had a higher soluble Al concentration than those containing less gibbsite at equivalent pH levels.The experimental results from treatment of soil samples with H2SO4 solutions and the analytical results of acid sulfate soils also showed the similar trend.     

Nature of redox concentrations in a sequence of agriculturally developed acid sulfate soils in Thailand

Potential acid sulfate soils (PASS) are drained for agriculture, resulting in the formation of active acid sulfate soils (AASS), which gradually evolve into post-active acid sulfate soils (PAASS). Various redox concentrations (precipitates, costings, and mottles) occur in these soils as a result of pedogenic processes including biological activity and effects of land management. Although several studies have determined the mineralogy and geochemistry of ASS, the mineralogy and geochemistry of redox concentrations occurring in a sequence of ASS through PASS to PAASS have not been investigated. This study examined the mineralogy and geochemistry of redox concentrations and matrices within 5 PASS, 8 AASS, and 5 PAASS in Thailand. The labile minerals were predominantly controlled by oxidation status and management inputs. The unoxidized layers of PASS, AASS, and PAASS contained pyrite and mackinawite. The oxidation of Fe sulfides caused acidification and accumulation of yellow redox concentrations of jarosite and Fe (hydr)oxides at shallow depths. As the soils became well developed, they were recognized as PAASS, and the jarosite and goethite transformed to hematite. As ASS were drained, Co, Mn, Ni, and Zn moved downward and were associated with Fe sulfides and Mn oxides in the unoxided layer. Concentrations of As, Cu, Cr, Fe, and V did not change with depth because these elements became associated with jarosite and Fe (hydr)oxides in yellow and red redox concentrations, as well as the root zone, in the partly oxidized layer of AASS and PAASS. Arsenic was associated with pyrite under reducing conditions.     

两种钾肥对湖北棉区棉花养分吸收及经济效益的影响

通过田间试验研究了钾肥用量(K2O 75、150、225 kg/hm2)与种类对棉花产量、养分吸收及经济效益的影响。结果表明:施硫酸钾与硫酸钾镁都能增加产量,提高养分含量及经济效益,两者相比,在低、中、高3个水平上棉花产量前者比后者分别提高3.5%、3.2%和1.4%;相比硫酸钾镁,施硫酸钾可使棉花对氮、磷的吸收量增加,棉花根的氮含量平均增加13.9%,茎的磷含量平均增加2.7%,但对钾、钙、镁、硫的吸收量影响较少。施用硫酸钾比施用硫酸钾镁所获的效益平均高540元/hm2,且在施K2O 75 kg/hm2处理所获效益最高,比不施钾肥多获效益10 350元/hm2。     

某极度酸化的酸性硫酸盐土壤中可溶性和交换性酸的特征

An extremely acidified acid sulfate soil(ASS) was investigated to characterise its soluble and exchangeable acidity,The results showed that soluble acidity of a sample dtermined by titration with a KOH soulution was much significantly greater than that indicated by pH measured using a pH meter,paricularly for the extremely acidic soil samples,This is because the total soluble acidity of the extremely acidic soil samples was mainly composed of various soluble Al and Fe species,possibly in forms of Al sulfate complexes(e.g.,AlSO4^ ) and feerous Fe(Fe^2 )_,It is therefore suggested not to use pH alone as an indicator of soluble acidity in ASS,particularly for extremely acidic ASS,It is also likely that AlSO4^ actively participated in cation exchange reactions.It appears that the possible involvement of this Al sulfate cation in the cation adsorption has significant effect on increasing the amount of acidity being adsorbed by the soils.     

Foliar manganese,zinc and boron application effects on mineral nutrition of an experimental olive grove (cv. “Chondrolia Chalkidikis”)

A 6-month field experiment (from October to March) was conducted in a 20-year-old experimental grove of the Aristotle University of Thessaloniki in order to enhance its micronutrient levels and assess the effect of micronutrient foliar application manganese, zinc and boron (Mn, Zn and B) on mineral nutrition, chlorophyll concentration and chlorophyll fluorescence parameters (F_v/F_m, F_v/F₀ and Performance index, PI) of the olive trees (cv. “Chondrolia Chalkidikis”). The experiment consisted of four treatments (Control-C: trees sprayed with deionized water, T50: trees sprayed with 50 mg/L Mn, Zn and B, T100: trees sprayed with 100 mg/L Mn, Zn and B, T200: trees sprayed with 200 mg/L Mn, Zn and B); the three micronutrients were applied in the forms of manganese sulfate (MnSO₄), zinc sulfate (ZnSO₄) and boric acid (H₃BO₃), respectively. The results showed that the most effective treatment for the enhancement of foliar Mn and B levels was T200, while for the increase of Zn levels was T100. In addition, significant differences among the treatments were recorded for most leaf nutrient concentrations (with the exception of potassium (K), which was not influenced by foliar treatment, the other macronutrients, such as calcium (Ca), magnesium (Mg), phosphorus (P) and nitrogen (N), as well as iron (Fe), obtained their maximum concentrations, at the end of the experiment, in C or T50 treatment). Chlorophyll concentrations were not influenced by foliar treatment. Concerning chlorophyll fluorescence parameters (F_v/F_m, F_v/F₀ and P index), significantly lower values were found in the control (C) trees, compared to the other three treatments, so it seems that a chlorophyll fluorescence technique may be used to detect micronutrient deficiencies in olive groves. However, from all the leaf nutrient concentrations determined, it was found that with the exceptions of: 1) Mn concentrations in the C, T50 and T100 treatments, which were marginal, or slightly deficient; 2) B and Zn concentrations in the C and T50 treatments, which were slightly deficient and marginal, respectively; 3) some K concentrations during the early spring period, which were slightly deficient, all the other concentrations were within the normal levels of sufficiency or within the optimum range, so no serious nutrient deficiency was detected.     

Sources,Rates and Time of Nitrogen Application on Maize Crops under No-Tillage System

Quantitatively, nitrogen (N) is the foremost nutrient for maize crops (Zea mays L.), but the N source to increase the grain productivity still needs more investigation. Thus, the aim of this experiment was to study sources, rates and time of N application on the crop yield and agronomic characteristics of the maize under no-tillage system. The experiment was carried out during two growing seasons on an Oxisol under the factorial 5 × 3 × 3 scheme with five N rates (0, 50, 100, 150, and 200 kg ha^?1) and three sources (ammonium-sulfate-nitrate as inhibitor of the nitrification (ASN+I), ammonium sulfate (AS) and urea); we applied them two times with four replicates: first time at the sowing or later under side dressing when the plants had the six leaves stage. In the first year, the sources of N had no influence on the number of grain line /ear (NGLE), grain number/line (GNL), total number of grain/ear (TNFE), biomass of 100 grain, plant height (PH), height of the first ear insertion (AFEI) and stalk diameter, in contrast with the foliar N content and the crop yield. Early fertilization with N at the sowing time can afford applications as well as the total side dressing. The increase of the rates had positive influence on the N foliar content, plant height and 100 grains biomass. The highest productivities were found with rates above the threshold of 150 kg ha^?1, no matter the sources and the fertilization time.     

星形孢菌素产生菌的选育研究

用紫外线和微波复合诱变星形孢菌素产生菌(Stretomyces sp.4138),以硫酸链霉素抗性偶联进行筛选。结果表明:紫外线处理50s后,在含硫酸链霉素0.8μg/ml的分离培养基上筛选到突变株HZ-09,比原始菌株H-0效价提高了30.46%;再以HZ-09为出发菌株进行微波处理30s后,硫酸链霉素抗性筛选获得突变株HW-25,比原始菌株H-0效价提高了284.20%。菌株HW-25经多次传代,遗传性状稳定。     

Observations on the bismuth sulfide colorimetric procedure for sulfate analysis in soil

Abstract

The bismuth sulfide and methylene blue colorimetric finishes for soil sulfate determination by the Johnson‐Nishita distillation method were examined and compared. Both procedures gave comparable results when applied to soils and soil extracts, but the bismuth method was more rapid and more reliable. Nitrogen flow rate over the range 100–500 ml/min was not critical for the bismuth method, provided appropriate distillation times were employed. However, the release and transfer of hydrogen sulfide in the bismuth method was effected in one‐third of the time required for the méthylène blue finish, largely due to the elimination of a gas‐washing step. Predrying of soil extract samples increased recovery of hydrogen sulfide with the bismuth procedure arid could be used to increase sensitivity. Nitrate interference was observed with the bismuth procedure but attributed to interference during the reduction step. The bismuth procedure can readily be adapted for microdetermination in the 0–40 ppm sulfate‐S range.     

澳大利亚东部地区一些酸性硫酸盐土壤磷的特征

Forty-five acid sulfate topsoil samples (depth < 0.5 m) from 15 soil cores were collected from 11 locations along the New South Wales coast, Australia. There was an overall trend for the concentration of the HC1-extractable P to increase along with increasing amounts of organic C and the HCl-extractable trivalent metals in the topsoils of some less-disturbed acid sulfate soils (pH < 4.5). This suggests that inorganic P in these soils probably accumulated via biological cycling and was retained by complexation with trivalent metals or their oxides and hydroxides. While there was no clear correlation between pH and the water-extractable P, the concentration of the water-extractable P tended to increase with increasing amounts of the HCl-extractable P. This disagrees with some established models which suggest that the concentration of solution P in acid soils is independent of total P and decreases with increasing acidity. The high concentration of sulfate present in acid sulfate soils appeared to affect the chemical behavior of Pin these soil systems. Comparison was made between a less disturbed wetland acid sulfate soil and a more intensively disturbed sugarcane acid sulfate soil. The results show that reclamation of wetland acid sulfate soils for sugarcane production caused a significant decrease in the HCl-extractable P in the topsoil layer as a result of the reduced bio-cycling of phosphorus following sugarcane farming. Simulation experiment shows that addition of hydrated lime had no effects on the immobilization of retained P in an acid sulfate soil sample within a pH range 3.54.6. When the pH was raised to above 4.6, soluble P in the soil extracts had a tendency to increase with increasing pH until the 15th extraction (pH 5.13). This, in combination with the poor pH-soluble P relationship observed from the less-disturbed acid sulfate soils, suggests that soluble P was not clearly pH-dependent in acid sulfate soils with pH < 4.5.