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Effects of Soil Properties on Phosphorus Subsurface Migration in Sandy Soils

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Pedosphere 2008年第5期18卷 599-610页

作者： ZHANG Ming-Kui college of Natural resource and environmental sciences Zhejiang University Huajiachi Campus Hangzhou 310029（China）.

The soil factors influencing the potential migration of dissolved and particulate phosphorus(P) from structurally-weak sandy subsoils were evaluated by means of soil column leaching experiments. Soil colloids were extracted from two types of soils to make the colloid-bound forms of P solution. Eight sandy soils with diverse properties were collected for packing soil columns. The effects of influent solutions varying in concentrations of colloids,P,and electrolyte,on the transport of P and quality of leachates were characterized. P migration in the soils was soil property-dependent. High soil electrical conductivity values retarded the mobility of colloids and transportability of colloid-associated P(particulate P) . Soil electrical conductivity was negatively correlated with colloids and reactive particulate P(RPP) concentrations in the leachates,whereas,the total reactive P(TRP) and dissolved reactive P(DRP) concentrations in the leachates were mainly controlled by the P adsorption capacity and the P levels in the subsoil. The reactive particulate P in the leachates was positively correlated with the colloidal concentration. Increased colloidal concentration in the influent could significantly increase the colloidal concentration in the leachates. Elevated P concentration in the influent had little effect on P recovery in the leachates,but it resulted in significant increases in the absolute P concentration in the leachates.

关键词： colloidal type electrical conductivity P adsorption capacity P subsoil migration sandy soil

QTLs for Rice Leaf Chlorophyll Content Under Low N Stress

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Pedosphere 2004年第2期14卷 145-150页

作者： FANGPing YUXiao-Min ZHURi-Qing WUPing collegeofenvironmentalandresourcesciences ZhejiangUniversityHangzhou310029（China）.E-mail：pfang@*** collegeofLifesciences ZhejiangUniversityHangzhou310029（China）

Quantitative trait loci (QTLs) for chlorophyll content of a rice leaf weremapped on to the molecular marker linkage map of a double-haploid (DH) population derived from across between two rice varieties 'IR64' and 'Azucena' in both nutrient solutionand soil cultureexperiments to detect rice nitrogen nutrition status under low N stress A chlorophyll meter was usedto measure the soil plant analysis development (SPAD) value of the topmost fully expanded leaf asthe index of chlorophyll content thatexpressed nitrogen status in rice plants. Totally 3 QTLs forSPAD values, two on chromosome 3 located at interval RG179-CDO337 and RG348-RZ329, respectively, andone on chromosome 10 at interval RZ500-RG134, were detected under stressed conditions of low N inthe soil and/or nutrient solution culture experiments. One QTL located at interval RG179-GDO337 onchromosome 3 associated with a relative change in SPAD value from a high N level to a low N level inthe soil culture experiment was also *** on the different responses to low N stressbetween the two parents, it was supposed that the QTLs identified in this study associated withnitrogen efficiency in rice at low N levels might be useful in applying marker technology to ricebreeding programs.

关键词： chlorophyll meter nitrogen efficiency QTLs rice (Oryza sativa L.) SPADvalue

Adsorption of Metsulfuron and Bensulfuron on a Cationic Surfactant-Modified Paddy Soil

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Pedosphere 2007年第1期17卷 101-108页

作者： LIAO Min XIE Xiao-Mei college of environmental and resource sciences Department of Resources Science Zhejiang University Hangzhou 310029 （China）

Adsorption isotherms of metsulfuron and bensulfuron on a hexadecyltrimethylammonium （HDTMA） bromide-modified paddy soil under different ionic strengths, with divalent cation Cu^2＋, or having different pH were studied to describe their adsorptive behavior, and to try to explain the adsorption process of a sulfonylurea compound with a carbamoylsulfamoyl group in the modified soil environment. All the adsorption isotherms fitted the Freundlich equation well, and the HDTMA treatment of paddy soil dramatically enhanced adsorption capacity of metsulfuron or bensulfuron. Also, an increase of ionic strength and the addition of divalent heavy metal cation Cu^2＋ on the HDTMA-modified paddy soil increased the adsorption of metsulfuron or bensulfuron. Additionally, for metsulfuron and bensulfuron in the aqueous phase, adsorption capacity of the HDTMA-modified paddy soft gradually increased with decreasing pH.

关键词： adsorption bensulfuron cationic surfactant metsulfuron paddy soil

Effect of Lead-Zinc Interaction on Size of Microbial Biomass in Red Soil

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Pedosphere 1998年第2期8卷 143-148页

作者： K. S. KHAN and HUANG CHANGYONG college of Natural resources and environmental sciences, zhejiang Agricultural university, hangzhou 310029 (china) Coll. National Research and Environment Science Zhejiang Agricultural University Hangzhou 310029 China

A laboratory incubation experiment was conducted to evaluate the effects of lead and zinc applied alone or in various combinations on the size of microbial biomass in a red soil. Treatments included the application of lead at six different levels i.e., 0 (background), 100, 200, 300, 450 and 600 μg g -1 soil along with each of the four levels of zinc (0, 50, 150 or 250 μg g -1 soil). Application of lead or zinc alone to soil significantly ( P <0.001) affected the soil microbial biomass. The microbial biomass carbon (C mic ), biomass nitrogen (N mic ) and biomass phosphorus (P mic ) decreased sharply in soils contaminated with lead or zinc. Combined application of lead and zinc resulted in a greater biocidal effect on soil microbial biomass, which was significantly higher ( P <0.001) than that when either lead or zinc was applied alone. Consistent increase in the biomass C:N and decline in the biomass C:P ratios were also observed with the increased metal (Pb and Zn) toxicity in the soil.

关键词： interaction lead microbial biomass red soil zinc

Signal interaction between nitric oxide and hydrogen peroxide in heat shock-induced hypericin production of Hypericum perforatum suspension cells

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Science china(Life sciences) 2008年第8期51卷 676-686页

作者： XU MaoJun, DONG JuFang & ZHANG XinBo Institute of Natural resource and environmental sciences, zhejiang Gongshang university, hangzhou 310035, china 1. Institute of Natural resource and environmental sciences Zhejiang Gongshang University Hangzhou 310035 China

Heat shock(HS, 40℃, 10 min) induces hypericin production, nitric oxide(NO) generation, and hydrogen peroxide(H2O2) accumulation of Hypericum perforatum suspension ***(CAT) and NO spe-cific scavenger 2-4-carboxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide(cPTIO) suppress not only the HS-induced H2O2 generation and NO burst, but also the HS-triggered hypericin *** contents of the cells treated with both NO and H2O2 are significantly higher than those of the cells treated with NO alone, although H2O2 per se has no effects on hypericin production of the cells, which suggests the synergistic action between H2O2 and NO on hypericin *** treatment enhances H2O2 levels of *** cells, while external application of H2O2 induces NO generation of ***, the results reveal a mutually amplifying action between H2O2 and NO in *** *** treatment inhibits both HS-induced H2O2 accumulation and NO generation, while cPTIO can also suppress H2O2 levels of the heat shocked *** results imply that H2O2 and NO may enhance each other's levels by their mutually amplifying action in the heat shocked *** NAD(P)H oxidase inhibitor diphenylene iodonium(DPI) and nitric oxide synthase(NOS) inhibitor S,S′-1,3-phenylene-bis(1,2-ethanediyl)-bis-isothiourea(PBITU) not only inhibit the mutually amplifying action between H2O2 and NO but also abolish the synergistic effects of H2O2 and NO on hypericin production, showing that the synergism of H2O2 and NO on secondary metabolite biosynthesis might be dependent on their mutual *** together, data of the present work demonstrate that both H2O2 and NO are essential for HS-induced hypericin production of *** suspension ***, the results reveal a special interaction between the two signal molecules in mediating HS-triggered secondary metabolite biosynthesis of the cells.

关键词： Hypericum perforatum cells hypericin heat shock nitric oxide hydrogen peroxide signal interaction

Influence of Particle Size on Magnetic Properties of Soils in zhejiang Province, china

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Pedosphere 2000年第1期10卷 81-88页

作者： LU SHENGGAO (college of Environment and resource, zhejiang university, hangzhou 510029 (china)) 浙江大学浙江杭州 310029

The relationship between magnetic properties and particle size of soils derived from metamorphic rock, basalt, granite, Quaternary red clay, limestone and mudstone from zhejiang Province, East china was studied. Based on the variations of the mass magnetic susceptibility (X), anhysteretic remanent magnetization (ARM), and saturation isothermal remanent magnetization (SIRM) with soil particle size, the relationship could be classified into three groups. For the soils derived from metamorphic rock and basalt, magnetic values were the highest in the gravel and coarse sand fractions and decreased with decreasing soil particle size. The soils derived from sedimentary rock had a bimodal distribution of magnetic values, with peaks in 1-0.5 and 0.005-0.000 5 mm fractions. The soil developed on granite was characterized by a peak of magnetic value in 0.001-0.000 5 mm fractions. Frequency-dependent susceptibility (Xfd ) and ratics of magnetic parameters (ARM/X, SIRM/X and SIRM/ARM) of soil particle fractions showed that variations in ferrimagnetic grain size paralleled those in particle size. Xfd peaked in clay fraction and decreased with increasing particle size, irrespective of soil parent materials. The acquisition curves of IRM and demagnetization parameter of different soil particles indicated that there were different magnetic minerals assemblages in different particle fractions.

关键词： soil particle soil parent material magnetic property zhejiang Province

Nutrient Uptake and Use Efficiency of Irrigated Rice in Response to Potassium Application

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Pedosphere 2004年第1期14卷 125-130页

作者： HUHong WANGGuang-Huo DepartmentofresourceScience CollegeofEnvironmentalandResourceScienceZhejiangUniversityHangzhou310029（China）

Potassium is one of the most important nutrients for rice production in many areas of Asia, especially in southeast china where potassium deficiency in soil is a widespread problem. Field experiments were conducted for four consecutive years in Jinhua City, zhejiang Province, to determine utilization of nutrients (N, P and K) by inbred and hybrid rice and rice grain yields as affected by application of potassium fertilizer under irrigated conditions. Grain yield and nutrient harvest index showed a significant response to the NPK treatment as compared to the NP treatment. This suggested that potassium improved transfer of nitrogen and phosphorus from stems and leaves to panicles in rice plants. N and P use efficiencies of rice were not strongly responsive to potassium, but K use efficiency decreased significantly despite the fact that the amount of total K uptake increased. A significant difference between varieties was also observed with respect to nutrient uptake and use efficiency. Hybrid rice exhibited physiological advantage in N and P uptake and use efficiency over inbred rice. Analysis of annual dynamic change of exchangeable K and non-exchangeable K in the test soil indicated that non-exchangeable K was an important K source for rice. Potassium application caused an annual decrease in the concentration of available K in the soil tested, whereas an increase was observed in non-exchangeable K. It could be concluded that K fertilizer application at the rate of 100 kg ha-1 per season was not high enough to match K output, and efficient K management for rice must be based on the K input/output balance.

关键词： nutrient uptake nutrient use efficiency paddy soil potassium irrigatedrice

Quantification of the effects of management factors on maize (Zea mays L.) and cotton(Gossypium hirsutum L.) residues decomposition rate

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Journal of environmental sciences 2002年第2期14卷 165-172页

作者： JONES Chilima, HUANG Chang yong, WU Ci fang (college of Natural resources and Environment, zhejiang university, hangzhou 310029, china. college of Natural resources and Environment Zhejiang University Hangzhou 310029 China

Efforts to quantify management effects on decomposition rate of added substrates to the soil is important especially where such information is to be used for prediction in mathematical or simulation models. Using data from a short term (60 days) greenhouse simulation study, a procedure for quantifying effects of management on SOM and substrate decomposition is presented. Using microbial growth rate u (q), microbial efficiency in substrate utilization e (q), specific decomposition rates for added plant residues to two contrasting soils, red earth (Ferrasol) and black earth (Acrisol) were estimated. The treatments included straw addition + buried, (T1); straw addition + mineral N (T2); and straw addition + tillage, (T3). Sampling was done every 15 days. Straw decomposition rate was affected by external mineral N sources (Urea 46% N). Addition of an external N source significantly increased decomposition rates. The study could not, however, fully account for the effect of tillage on residues because of the limited effect of the tillage method due to the artificial barrier to mechanical interference supplied by the mesh bags. It is concluded that using few decomposer parameters, decomposition rates and consequently SOM trends in a soil system can be monitored and quantification of the influence of perturbations on decomposition rate of added substrates possible.

关键词： management factors residue decomposition rate maize cotton red soil black soil

Commelina communis L.: Copper Hyperaccumulator Found in Anhui Province of china

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Pedosphere 1997年第3期7卷 207-210页

作者： TANG SHIRONG HUANG CHANGYONG and ZHU ZUXIANG (Department of Soil Science, college of environmental sciences and Natural resources, zhejiang Agricultural university, hangzhou 310029 china) Department of Soil Science College of Environmental Sciences and Natural Resources Zhejiang Agricultural University Hangzhou 310029 China

Commelina communis L. growing over some new copper mining wastelands at Bijiashan, Tongling City of Anhui Province, china, was found to be a copper hyperaccumulator. Its copper concentrations were 2707-6159 (4439±2434) mg kg-1, 369-831 (731±142) mg kg-1, and 429-587 (547±57) mg kg-1, respectively, in the roots, stems, and leaves. The soils supporting the growth of the species had a copper concentration ranging from 4620 to 5020 mg kg-1 and averaging 4835±262 mg kg-1, suggesting that the species could not only grow on heavily copper-contaminated soils but also accumulate extraordinarily high concentration of copper. Thus, it shows great potential in the phytoremediation of copper-contaminated soils,the restoration of mined land, geochemical prospecting, and the study of environmental pollution changes.

关键词： Anhui Province Commelina communis L. copper hyperaccumulator