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Degradation of soil Properties due to Erosion on Sloping Land in Southern Jiangsu Province,china

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Pedosphere 2004年第1期14卷 17-26页

作者： ZHANGYan PENGBu-Zhuo GAOXiang YANGHao LMCP InstituteofSoilScienceChineseAcademyofSciencesNanjing210008（China） DepartmentofUrbanandResourcesscience NanjingUniversityNanjing210093（China）

soil erosion accelerates soil degradation. Some natural soils and cultivated soils on sloping land in southern Jiangsu Province, china were chosen to study soil degradation associated with erosion. soil erosion intensity was investigated using the 13.Cs tracer method. soil particle-size distribution, soil organic matter (OM), total nitrogen (TN) and total phosphorus (TP) were measured, and the effects of erosion on soil physical and chemical properties were analyzed statistically using SYSTAT8.0. Results indicated that erosion intensity of cultivated soils was greater than that of the natural soils, suggesting that cultivation increased soil loss. Erosion also led to an increase of coarser soil particle proportion, especially in natural soils. In addition, silt was the primary soil particle lost due to erosion. However, in cultivated fields, coarser soil particles over time were attributed not only to soil erosion but also to mechanical eluviation as a result of farming activities. Moreover, erosion caused a decrease in soil OM, TN and TP as well as thinning of the soil layer.

关键词： ^(13.)Cs coarser soils nutrients soil degradation soil layer

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 {3. 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

Classification of Ferrallitic soils in chinese soil Taxonomy

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Pedosphere 2000年第2期10卷 125-133页

作者： GONG ZITONG CHEN ZHICHENG ZHAO WENJUN and SHI HUA(institute of soil science, the {3. academy of sciences, P.O. Box 821, Naroing 210008 china) 中科院南京土壤所江苏南京 210008

The development of the classification of ferrallitic soils in china is reviewed and the classification ofFerralisols and Ferrisols in chinese soil Taxonomy is introduced in order to discuss the correlation betweenthe ferrallitic soil classification in the chinese soil Taxonomy and those of the other soil classification *** the former soil classification systems of china, the ferrallitic soils were classified into the soil groups ofLatosols, Latosolic red soils, Red soils, Yellow soils and Dry red soils, according to the combination of soilforming conditions, soil-forming processes, soil features and soil properties. In the chinese soil Taxonomy,most of ferrallitic soils are classified into the soil orders of Ferralisols and Ferrisols based on the diagnostichorizons and/or diagnostic characteristics with quantitatively defined properties. Ferralisols are the soilsthat have ferralic horizon, and they are merely subdivided into one suborder and two soil groups. Ferrisolsare the soils that have LAC-ferric horizon but do not have ferralic horizon, and they are subdivided intothree suborders and eleven soil groups. Ferralisols may correspond to part of Latosols and Latosolic red *** may either correspond to part of Red soils, Yellow soils and Dry red soils, or correspond to part ofLatosols and Latosolic red soils.

关键词： Ferralisols Ferrisols chinese soil Taxonomy

Distribution and Migration of Heavy Metals in Undisturbed Forest soils:A High Resolution Sampling Method

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Pedosphere 2008年第3期18卷 386-393页

作者： RUAN Xin-Ling ZHANG Gan-Lin NI Liu-Jian HE Yue State Key Laboratory of soil and Sustainable Agriculture Institute of Soil Science chinese academy of sciences Nanjing 210008 （China） Graduate School of the chinese academy of sciences Beijing 100049 （China） College of Resources and Environmental sciences Nanjing Agricultural University Nanjing 210095 （China）

The vertical distribution and migration of Cu,Zn,Pb,and Cd in two forest soil profiles near an industrial emission source were investigated using a high resolution sampling method together with reference element ***-meter soil profile was sectioned horizontally at 2 cm intervals in the first 40 cm,5 cm intervals in the next 40 cm,and 10 cm intervals in the last 20 *** migration distance and rate of heavy metals in the soil profiles were calculated according to their relative concentrations in the profiles,as calibrated by the reference element *** enrichment of heavy metals appeared in the uppermost layer of the forest soil,and the soil heavy metal concentrations decreased down the profile until reaching their background *** calculated average migration rates of Cd,Cu,Pb,and Zn were 0.70,0.3.,0.3.,and 0.76 cm year-1,respectively,which were comparable to other methods.A simulation model was proposed,which could well describe the distribution of Cu,Zn,Pb,and Cd in natural forest soils.

关键词： distribution heavy metals high resolution sampling method migration rate

Model Research on the Effect of Surface Film on Ammonia Volatilization from Rice Field

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Agricultural sciences in china 2002年第9期1卷 1029-1033页

作者： ZHUANG Shun-yao, YIN Bin and ZHU Zhao-liang(institute of soil science , {3. academy of sciences , nanjing 210008 , P.R.china) institute of soil science Chinese Academy 9f Sciences Nanjing 210008 P.R. China

Pan and field experiments were conducted to investigate the effect of surface film on ammonia volatilization from water and paddy soil. The results showed that the addition of the surface film on floodwater reduced the rate of ammonia volatilization, however, the reduction of the latter varied greatly with its rates of addition. Jayaweera-Mikkelsen ammonia volatilization model with the introduction of a parameter Kf, a relative measure of the resistance of the surface film on ammonia volatilization, was used to elucidate the effectiveness of the surface film on lowering ammonia volatilization. The Kf value was calculated from the results ob-

关键词： Surface film Ammonia volatilization J-M model Coefficient of resistance

Environmental Issues Related to Chemical Fertilizer Use in china

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Pedosphere 1996年第4期6卷 289-303页

作者： CAO ZHIHONG (LMCP, institute of soil science, Academia Sinica, P. O. Box 821,{3. china) LMCP Institute of Soil Science Academia Sinica P. O. Box 821 Nanjing 210008 China

The current status of chemical fertilizers production and consumption in china as well as their important roles in chinese modern agriculture are discussed with special concerns to the environmental issues related to chemical fertilizer use. On the one hand, the total amount of chemical fertilizer produced is insufficient to meet the agricultural needs. On the other hand, the production and consumption of chemical fertilizers in china are obviously not balanced. In some areas over application of nitrogen fertilizers and loss of phosphate fertilizer due to {3. erosion have resulted in some undesirable environmental problems such as increase of nitrate in water and eutrophication of water bodies. Maximum scientific uses of organic manures in combination with reasonable use of chemical fertilizers are part of good practices not only in increasing {3. productivity and keeping sustainable agriculture development but also in mimimizing their detrimental effects on the environment.

关键词： chemical fertilizer environmental issues modern agriculture

Preliminary study on assessment of nutrient transport in the Taihu Basin based on SWAT modeling

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science china Earth sciences 2006年第z1期49卷 135-145页

作者： LAI Geying, YU Ge & GUI Feng nanjing institute of Geography & Limnology, chinese {3. of sciences, nanjing 210008, china The Graduate School of the chinese {3. of sciences, Beijing 10003., china Key Lab of Poyang Lake Ecological Environment and Resource Development, Jiangxi Normal University, Nanchang 3.0027, china 1. nanjing institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China2. The Graduate School of the Chinese Academy of Sciences Beijing 100039 China3. Key Lab of Poyang Lake Ecological Environment and Resource Development Jiangxi Normal University Nanchang 330027 China

With the Taihu Basin as a study area, using the spatially distributed and mechanism-based SWAT model, preliminary simulations of nutrient transport in the Taihu Basin during the period of 1995～2002 has been carried out. The topography, soil, meteorology and land use with industrial point pollution discharge, the loss of agricultural fertilizers, urban sewerage, and livestock drainages were all considered in the boundary conditions of the simulations. The model was calibrated and validated against water quality monitoring data from 2001 to 2002. The results show that the annual total productions of nitrogen (TN) and phosphorus (TP) into Lake Taihu are 40000t and 2000t respectively. Nutrient from the Huxi Region is a major resource for Lake Taihu. The non-point source (surface source) pollution is the main form of catchment sources of nutrients into Lake Taihu,occupied TN 53. and TP 56% respectively. TN and TP nutrients from industrial point pollution discharge are 3.% and 16%, and sewerage in both forms of point source and non-point source are TN 3.% and TP 47%. Both the loss of agricultural fertilizers and livestock drainages from the catchment should be paid more attention as an important nutrient source. The results also show that SWAT is an effective model for the simulation of temporally and spatially nutrient changes and for the assessment of the trends in a catchment scale.

关键词： Taihu Basin, nutrients, catchment resource inputs, SWAT model, simulation.

Effect of Perched Water Tables on Aluminosilicate Stability and soil Genesis

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Pedosphere 2000年第3期10卷 247-256页

作者： ZHANG MIN , GONG ZITONG and A. D. KARATHANASIS College of Resources and Environment, Shandong Agricultural University, Tai’an 271018 (china) institute of soil {3., the chinese academy of {3.s, nanjing 210008 (china) College of Agriculture, U asteur.ivic.ve

The mineral stability and solute activities of soil solution extracted from selected horizons of seven studied pedons of Alfisols in Kentucky, USA, and the relationship between distribution of iron-manganese concretions and the restrictive layers were investigated. The results showed that the genesis and development of these soils and mineral weathering trends were strongly influenced by the depth of bedrock and the presence of perched water tables at lithic (limestone) interfaces due to the dissolution and buffering effect of limestone bedrock. The extractable Mg/Ca ratio as depth function and soil depth above bedrock could be used as indices of weathering and degree of soil development. Maximum iron-manganese concretion accumulation was found to occur in the horizon overlying clay horizon (>40% clay) with a sharp increase in clay content (>10%), which suggested that zones of Fe-Mn concretion accumulation in soils of the Inner Bluegrass Region appeared to be a sensitive genetic indicator of argillic horizons with restrictive permeability.

关键词： iron-manganese concretion perched water table soil environment soil genesD

soil Respiration During a Soy bean-Growing Season

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Pedosphere 2006年第2期16卷 192-200页

作者： YANG Lan-Fang CAI Zu-Cong State Key Laboratory of soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China）. School of Resources and Environmental science Hubei University Wuhan 430062 （China） School of Environmental Studies China University of Geosciences Wuahn 430074 （China）

soil respiration induced by soybean cultivation over its entire growing season and the factors influencing soil respiration were investigated to examine the seasonal pattern of soil respiration induced by soybean cultivation, explore soybean growth and photosynthesis on soil respiration, and determine the temperature dependence on soil respiration. soil respiration in a pot experiment with and without soybean plants was sampled using the static chamber method and measured using gas chromatograph. Air temperature was a dominant factor controlling soil respiration rate in unplanted soil. Additionally, rhizosphere respiration comprised 62% to 98% of the soil respiration rate in the soybean-planted soil varying with the soybean growth stages. Harvesting aerial parts of soybean plant caused an immediate drop in the soil respiration rate at that stage. After harvesting the aerial parts of the soybean plant, a highly significant correlation between soil respiration rate and air temperature was found at the flowering stage （P 〈 0.01）, the pod stage （P 〈 0.01）, and the seed-filling stage （P 〈 0.05）. Thus, rhizosphere respiration during the soybean-growing period not only made a great contribution to soil respiration, but also determined the seasonal variation pattern of the soll respiration rate.

关键词： photosynthesis rhizosphere soil respiration soybean plant temperature effect