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Leaching of Nutrient Elements in a Red soil Derived from Quaternary Red Clay

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pedosphere 1998年第1期8卷 15-20页

作者： SHEN RENFANG and ZHAO QIGUO(laboratory of material cycling in pedosphere, institute of soil science, the chinese academy of sciences,P.O. Box 821, nanjing 210008 (china)) laboratory of material cycling in pedosphere Institute of Soil Science Chinese Academy of Sciences P.O. Box 821 Nanjing 210008 China

A red soil derived from Quaternary red clay was employed to study nutrient leaching with soil columns repacked in laboratory. The objective was to identify the effects of fertilization practices on leaching patterns and magnitudes of Ca2+, Mg2+, K+, NH+, and NO-. The treatments were CK (as a control), CaCO3,CaSO4, MgCO3, Ca(H2PO4)2, urea, KCI, and multiple (a mixture of the above-mentioned fertilizers). The fertilizers were added to the bare surface of the soil columns, and then the columns were leached with 120 mL deionized water daily through peristaltic pumps over a period of 92 days. Leaching processes of NH+, and NO- were only measured in CK, urea, and multiple treatments which were directly related to N *** showed that sole application of CaSO4, and Ca(H2PO4)2 scarcely had any effect on the leaching losses of Ca2+, Mg2+, and K+; the application of MgCO3 stimulated the leaching of Mg2+; the application of CaCOs promoted the leaching of Ca2+, Mg2+ and K+; urea treatment also promoted the leaching of K+ and NH+, and NO- leaching mainly occurred at late stage of leaching process in particular; under KCI treatment, leaching of Ca2+, Mg2+, and K+ was promoted to a large extent; under multiple treatment,leaching of Ca2+, Mg2+, K+, NH+, and NO- was all increased and NO- was mainly leached at the end of leaching process and still had a trend of increase.

关键词： fertilization nutrient leaching red soil

Effect of Combined Heavy Metal Pollution on Nitrogen Mineralization Potential,Urease and Phosphatase Activities in a Typic Udic Ferrisol

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pedosphere 1999年第3期9卷 251-258页

作者： ZHENG CHUNRONG TU CONG and CHEN HUAIMAN(laboratory of material cycling in pedosphere, institute of soil science, the chinese academy of sciences,nanjing 210008 (china))(Received April 20, 1999 revised June 2, 1999) 中科院南京土壤所江苏南京 210008 中科院南京土壤所江苏南京

Individual and combined effects of Cu, Pb, Zn and Cd on N mineralization, urease and phosphatase were examined in a Typic Udic Ferrisol in laboratory by employing an uniform design and a single factor *** pollution caused by heavy metals inhibited N mineralization (No value) and urease and phosphatase activities. The combined pollution of metals alleviated their toxicity to N mineralization to some extent,whereas aggravated the toxicity to urease and phosphatase. Phosphorous application could mitigate the toxic effect of heavy metals on phosphatase activities, while alleviating effect of N application on the toxicity of heavy metals to urease was inconsistent. However, the mitigating effect of the fertilizers was limited in heavily polluted soils.

关键词： heavy metal pollution N mineralization phosphatase urease

Modeling Nitrogen Mineralization in Paddy soils of Shanghai Region

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pedosphere 2003年第4期13卷 331-336页

作者： LI Hui-Lin, HAN Yong and CAI Zu-Conglaboratory of material cycling in pedosphere, institute of soil science, the chinese academy of sciences, P. O. Box 821, nanjing 210008 (china). E-mail: lihuilin@*** 中科院南京土壤所 Laboratory of Material Cycling in PedosphereCAS Nanjing 210008

Six paddy soils of Shanghai, china, were studied after 120 days of anaerobicincubation at 25 deg C and 35 deg C. Four models, the effective accumulated temperature model, theone-component first-order exponential model (the one-pool model), the two-component first-orderexponential model (the two-pool model), and the two-component first-order plus zero-orderexponential model including a constant term (the special model), were fitted to the data of observedmineral-N during incubation using non-linear regression procedures. The two-pool model and thespecial model gave the best fits amongst the four models, and parameters in the special model weremore reasonable than those in the other three. Results showed that the special model gave a betterprediction of nitrogen mineralization under flooded conditions than the other three models.

关键词： anaerobic incubation nitrogen mineralization paddy soil simulation model

Effect of Heavy Metal Pollution on Potassium Behavior in Typic Udic Ferrisol

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pedosphere 2000年第1期10卷 21-30页

作者： TUCONG ZHENGCHUNRONG 等 laboratoryofmaterialcyclinginpedosphere instituteofSoilScinecetheChineseAcademyofSciencesP.O.Box821Nanjing210008China laboratoryofmaterialcyclinginpedosphere instituteofSoilScinecetheChineseAcade

The indirect influence of heavy metal contamination of soil on nutrient availability, an important aspect of soil quality, may need to be taken into consideration when determining overall effects of heavy metals. A laboratory experiment was performed to study the effects of combined pollution of Cu, Ph, Zn and Cd on soil K status as indicated by chemical fractions, adsorption-desorption and quantity/intensity (Q/I) relationship of K in a Typic Udic Ferrisol (generally called red soil), by employing uniform design and single factor design. Compared to the control, content of exchangeable K was decreased, but that of soluble K increased in the samples contaminated with heavy metals. Due to heavy metal pollution, potassium adsorption was reduced by 5% to 22%, whereas the desorption percentage of adsorbed K increased by 2% to 32%. The Q/I curves shifted downward, potassium buffering capacity (PBCK) decreased, and equilibrium activity ratio values (ARoK) increased with increasing heavy metal pollution. These influences followed the sequences of Ph>Cu>Zn and combined pollution>single one. Displacement of K from canon exchange sites and decrease in soil CEC due to heavy metals should be responsible for the changes of soil K behaviours. The findings suggest that heavy metal pollution of soil might aggravate the degradation of soil K fertility by decreasing K adsorption and buffering capacity and increasing desorption.

关键词： heavy metals potassium behaviors Typic Udic Ferrisol

A Simulation Study on Effect of Surface Film-Forming material on Water Evaporation

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pedosphere 2001年第1期11卷 67-72页

作者： ZHUANG SHUNYAO, YIN BIN and ZHU ZHAOLIANG (institute of soil science, the chinese academy of sciences, nanjing 210008 (china)) 中科院南京土壤所江苏南京 210008

A greenhouse experiment was conducted to investigate the effect of surface film-forming material (SFFM), a mixture of 16-18-octadecanols by emulsification, on water evaporation. Air-dried soil with distilled water was incubated firstly for 7 days to reestablish soil biological activity and then for another 7 days after treated with SFFM at rates of 0, 1, 2, 4, 6 and 8 g m-2, respectively. Everyday during the 7-day incubation after addition of SFFM, water losses due to evaporation were ~measured by an electronic balance. The rate of water evaporation with the addition of SFFM was reduced significantly compared with the control treatment and the effectiveness of SFFM on water evaporation reduced with time. According to the equation expressions of the effect of SFFM on water evaporation, the half-life of electiveness of SFFM on water evaporation was introduced and calculated to analyze quantitative relationship between the effectiveness of SFFM on water evaporation and the addition rate of SFFM. The calculated half-life increased with the addition rate of SFFM and the confidence of the calculated values of the half-life was high, suggesting that the half-life of effectiveness of SFFM on water evaporation could be described quantitatively and may be helpful for ameliorating application method of SFFM and screening surface-film forming materials in order to improve nitrogen fertilizer use efficiency in flooded rice fields.

关键词： half-life of effectiveness surface film-forming material water evaporation

Effect of Cr(Ⅵ) and p-Chloroaniline Interaction on Their Reaction Behaviors on soil Colloids

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pedosphere 1999年第3期9卷 233-242页

作者： ZHOU DONGMEI and CHEN HUAIMAN(laboratory of material cycling in pedosphere, institute of soil science, the chinese academy of sciences,nanjing 21O008 (china))(Received April 14, 1999 revised June 8, 1999)

Adsorption of Cr(Ⅵ) and p-chloroaniline on three typical soil colloids and pH influence were studied using batch equilibrium method. Both of Cr(Ⅵ) and p-chloroaniline adsorption on the colloids could be well described by general adsorption simulation equations. The adsorption processes changed with media pH. When Cr(Ⅵ) and p-chloroaniline coexisted on soil colloids, their interactions could be observed in a certain pH range to be accompanied with Cr(Ⅵ) reduction, which clearly suggested that a surface catalytic reaction occurred in this system. soil colloid acted as an efficient catalyst for the interaction of Cr(Ⅵ) and p-chloroaniline. The pH values at which no interaction was observed were 4.0, 4.5 and 5.0 for the colloids of indigotic black soil, yellow-brown soil and latosol, respectively. Capillary electrophoresis used to analyze p-chloroaniline provided a high separation efficiency and short separation time, and needed no more extensive pretreatment of samples.

关键词： Cr(Ⅵ) interaction of pollutants p-chloroaniline soil colloids

Phenolic Acids in Plant-soil-Microbe System: A Review

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pedosphere 2002年第1期12卷 1-14页

作者： LI SHOUTIAN, ZHOU JIANMIN, WANG HUOYAN and CHEN XIAOQIN institute of soil science, the chinese academy of sciences, P. O. Box 821, nanjing S10008 (china) institute of soil science the Chinese Academy of Sciences P. O. Box 821 Nanjing 210008

Phenolic acids are very common compounds in pedosphere. Theobjective of this review was to summarize the current knowledge ofthe behaviors of phenolic acids in plant-soil microbe system. Whenphenolic acids originated form leaching, decomposition and exudationof living and dead plant tissues enter soils, they can reactphysiochemically with soil particle surfaces and/or incorporate intohumic matter. Phenolic acids desorbed from soil particle surfaces andremained in solution phase can be utilized by microbe as carbonsources and absorbed by plants.

关键词： allelopathic activity phenlic acids plant-soil-microbe system

Nutrient cycling and Balance in Red soil Agroecosystem and Their Management

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pedosphere 2000年第2期10卷 107-116页

作者： HE YUANQIU and LI ZHIMING.(institute of soil science, the chinese academy of sciences, P.O. Box 821, nanjing 210008 china) 中科院南京土壤所江苏南京 210008

An experiment was conducted in a red soil derived from Quaternary red clay in the Ecological ExperimentStation of Red soil, the chinese academy of sciences, located in Yingtan (28° 15′ 30″ N, 116° 55′ 30″E), Jiangxi Province. The results show that the major ways of nutrient loss are leaching and nitrogenvolatilization. Rationalizing crop distribution, stimulating nutrient recycling, and improving internal nutrientflow are effective measures to decrease nutrient loss and to promote nutrient utilization efficiency. Theimportant ways of regulating nutrient cycling and balance in the agroecosystem of the red soil are to establishoptimal eco-agricultural models, practice balanced fertilization and combine the cropping system with thelivestock system.

关键词： balance nutrient cycling red soil agroecosystem regulation options

Fractionation of Heavy Metals in soils as Affected by soil Types and Metal Load Quantity

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pedosphere 2002年第4期12卷 309-319页

作者： ZHOU DONGMEI, CHEN HUAIMAN, HAO XIUZHEN and WANG YUJUNinstitute of soil science, the chinese academy of sciences, nanjing 210008 (china) institute of soil science the Chinese Academy of Sciences Nanjing 210008

Two series of soil subsamples, by spiking copper (Cu), lead (Pb), zinc (Zn) and cadmium (Cd) in an orthogonal design, were prepared using red soil and brown soil, respectively. The results indicated that heavy metal fractions in these soil subsamples depended not only on soil types, but also on metal loading quantity as well as on interactions among metals in soil. Lead and Cu in red soil appeared mostly in weakly specifically adsorbed (WSA), Fe and Mn oxides bound (OX), and residual (RES) fractions. Zinc existed in all fractions except organic bound one, and Cd was major in water soluble plus exchangeable (SE) one. Different from the results of red soil, Pb and Cu was present in brown soil in all fractions except organic one, but over 75% of Zn and 90% of Cd existed only in SE fraction. Meanwhile, SE fraction for any metal in red soil was lower than that in brown soil and WSA and OX fractions were higher. It is in agreement with low cation exchange capacity and large amounts of metal oxides included in red soil. Metal fractions in soil, especially for water soluble plus exchangeable one, were obviously influenced by other coexisting metals. The SE fraction of heavy metals increased with increasing loading amounts of metals in red soil but not obviously in brown soil, which suggest that metal availability be easily affected by their total amounts spiked in red soil. In addition, more metals in red soil were extracted with 0.20 mol L-1 NH4Cl (pH 5.40) than that with 1.0 mol L-1 Mg(NO3)2 (pH 7.0), but the reverse happened in brown soil, implicating significantly different mechanisms of metal desorption from red soil and brown soil.

关键词： fraction heavy metal interaction ionic impulsion soil