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Temporal and spatial variations of δ^(15)N and δ^(18)O for atmospheric N_2O above the oceanic surface from Shanghai to Antarctica

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science china Earth sciences 2008年第6期51卷 899-910页

作者： ZHU RenBin1, LIU YaShu1, XU Hua2, MA Jing2 & SUN LiGuang1 1 institute of Polar Environment, University of science and Technology of china, Hefei 230026, china 2 state key laboratory of soil and sustainable agriculture, institute of soil science, chinese academy of sciences, nanjing 210091, china 1. institute of Polar Environment University of Science and Technology of China Hefei 230026 China 2. state key laboratory of soil and sustainable agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210091 China

During the 22nd chinese Antarctic Research Expedition (chinaRE-22), the atmospheric gas samples above the oceanic surface and near the surface were collected on the track for the scientific ship "Xuelong" and on Millor Peninsula of eastern Antarctica, respectively, using the Tedlar gas bags. Every day the sampling times were 10:00 and 22:00 (local time), respectively. In the laboratory, high-precision measurement of the isotopic compositions for N2O in these gas samples was conducted using Thermo Finnigan MAT-253 Isotopic Mass Spectrometer with a fully automated interface for the pre-GC concen-tration (PreCon) of trace gases. The temporal and spatial variations of δ 15N and δ 18O in atmospheric N2O were analyzed. The mean δ 15N and δ 18O-N2O values above the oceanic surface were (7.21±0.50)‰ and (44.52±0.52)‰, respectively. From 30°N to Antarctica, the δ 15N (6.05‰―7.88‰) linearly increased with the rate of about 0.01‰ with the latitude while the δ 18O (43.05‰―48.78‰) showed a large fluctua-tion. The δ 15N negatively correlated with air temperature and N2O concentration, and slightly positively correlated with δ 18O. The summertime variations of δ 15N and δ 18O-N2O appeared the same trend on Millor Peninsula of eastern Antarctica. They significantly positively correlated with each other and negatively with N2O concentration. The δ 15N and δ 18O-N2O at different sites averaged (7.42±0.35)‰ and (44.69±0.49)‰, respectively, slightly higher than those above the oceanic surface, significantly higher than those of atmospheric N2O in the low-latitude regions of Northern Hemisphere. The predominant factors affecting the spatial variations of δ 15N and δ 18O values were also discussed. The isotopic data given in this study can help to investigate the global and regional N2O budgets.

关键词： nitrous oxide Antarctica atmosphere δ^(15)N δ^(18)O isotope ocean

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Effects of chlorothalonil and carbendazim on nitrification and denitrification in soils

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Journal of Environmental sciences 2009年第4期21卷 458-467页

作者： LANG Man, CAI Zucong state key laboratory of soil and sustainable agriculture, institute of soil science, chinese academy of sciences,nanjing 210008, china [a]state key laboratory of soil and sustainable agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China

The effects of chlorothalonil and carbendazim on nitrification and denitrification in six soils in upland and rice paddy environments were investigated. laboratory aerobic （60% water holding capacity） and anaerobic （flooded） conditions were studied at 25℃ and fungicide addition rates of 5.5 mg/kg A. I. （field rate, FR）, 20 times （20FR） and 40 times （40FR） field rate, respectively. The results indicated that chlorothalonil at the field rate had a slight inhibitory effect on one soil only, and that soil did not nitrify much in the first place. But chlorothalonil at higher rates inhibited nitrification significantly in all soils. For soils JXP and JXU with a pH of less than 5.0, chlorothalonil almost completely stopped their nitrification at 20FR and 40FR during the whole 14 d incubation period. For soils HNP and HNU with a pH of greater than 8.0, chlorothalonil also significantly inhibit nitrification at 20FR and 40FR （p 〈 0.05）. However, NH4＋ that was added to the soil was also almost completely nitrified by the end of the incubation period in these two soils. The effects of chlorothalonil at 20FR and 40FR on the nitrification of JSP and JSU soils, with a pH of 5.4 and 7.2, respectively, were intermediate between the other soil types. Chlorothalonil had no effect on denitrification at the field rate and had little effect at the higher rates of application in some soils. Carbendazim had essentially no effect on nitrification and denitrification in soils assessed.

关键词： fungicide nitrification denitrification chlorothalonil carbendazim

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Potassium Fractions in soils as Affected by Monocalcium Phosphate,Ammonium Sulfate,and Potassium Chloride Application

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Pedosphere 2010年第3期20卷 368-377页

作者： WANG Huo-Yan, ZHOU Jian-Min, DU Chang-Wen and CHEN Xiao-Qin state key laboratory of soil and sustainable agriculture, institute of soil science, chinese academy of sciences, nanjing 210008 (china) [a] state key laboratory of soil and sustainable agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China)

soil potassium （K） deficiency has been increasing over recent decades as a result of higher inputs of N and P fertilizers concomitant with lower inputs of K fertilizers in china; however, the effects of interactions between N, P, and K of fertilizers on K status in soils have not been thoroughly investigated for optimizing N, P, and K fertilizer use efficiency. The influence of ammonium sulfate （AS）, monocMcium phosphate （MCP）, and potassium chloride application on K fractions in three typical soils of china was evaluated during 90-d laboratory soil incubation. The presence of AS significantly altered the distribution of native and added K in soils, while addition of MCP did not significantly affected K equilibrium in most cases. Addition of AS significantly increased water-soluble K （WSK）, decreased exchangeable K （EK） in almost all the soils except the paddy soil that contained considerable amounts of 2：1 type clay minerals with K added, retarded the formation of fixed K in the soils with K added, and suppressed the release of fixed K in the three soils without K added. These interactions might be expected to influence the K availability to plants when the soil was fertilized with AS. To improve K fertilizer use efficiency, whether combined application of AS and K was to be recommended or avoided should depend on K status of the soil, soil properties, and cropping systems.

关键词： fertilizers K availability K fixation K release

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Methane Emission from Natural Wetlands in china:Summary of Years 1995-2004 Studies

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Pedosphere 2007年第4期17卷 475-486页

作者： DING Wei-Xin CAI Zu-Cong state key laboratory of soil and sustainable agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China）.

From studies undertaken during 1995-2004, annual budgets of CH4 emissions from natural wetlands and its temporal and spatial variations were examined throughout china, and various factors influencing CH4 emissions were also evaluated. The seasonal variation in CH4 emissions that increased with increasing plant growth reached its peak in August; decrease in the emissions was found in freshwater marshes but not in peatlands. Emissions were mainly controlled by temperature and depth of standing water. Low CH4 emissions at the early plant growing stages were not because of deficiency of organic C for CH4 production but because of low temperatures. Low temperatures not only reduced CH4 production but also stimulated CH4 oxidation by lowering the activity of other aerobic microbes which left more 02 in the rhizosphere for methanotrophs. Low summer temperatures （below 20 ℃） in the Qinghai-Tibetan Plateau lowered CH4 production and CH4 emission resulting in little or no seasonal variation of emissions. Diel and spatial variation in CH4 emissions depended on plant species. For plants that transport CH4 using the pressure-driven convective through-flow mechanism, diel variation in CH4 emissions was governed by diel variation of solar energy load （that produces temperature and vapor pressure differences within various plant tissues） and stomatal conductance. For plants that transport gases using the molecular diffusion mechanism only, the diel variation of CH4 emissions was because of differences in the magnitude of O2 produced through photosynthesis and then delivered into the rhizomes and/or rhizosphere for CH4 oxidation. Emergent plants could transport more CH4 than submerged plants because the former transport CH4 directly into the atmosphere rather than into water as do submerged plants where CH4 can be further be oxidized during its diffusion from water to the atmosphere. Emergent plants with high gas transport capacity could not only transport more CH4 into the atmosphe

关键词： diel variation methane emission seasonal variation temporal variation wetland

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Quantitative Relationship Between Land Use and Phosphorus Discharge in Subtropical Hilly Regions of china

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Pedosphere 2003年第1期13卷 67-74页

作者： YANG JINLING and ZHANG GANLINinstitute of soil science, the chinese academy of sciences, nanjing 210008 (china) institute of soil science the Chinese Academy of Sciences Nanjing 210008 (China)

The increase of phosphorus concentration is a crucial factor causing the eutrophication of water body,while land use has an important impact on agricultural non-point sources (NPS) phosphorus discharge. Sevensites controlling the water in four sub-watersheds and the main exit of the Meicun Watershed of XuanchengCounty, Anhui Province, were investigated by dynamic monitoring of stream water and nutrient discharge,integrating interpretation of aerial image and GIS analysis to find out how the land use affects phosphorusloss with stream water in typical agriculture-forest watershed in subtropical china. These monitored sitesare different in structure of land use. Phosphorus concentration of the stream water was analyzed everyweek and at the next day of rainfall. The velocity of flow was measured by kinemometer to calculatethe runoff flux and phosphorus discharge. The results showed that the runoff flux and the discharges ofdissolved phosphorus (DP), particle-associated phosphorus (PAP) and total phosphorus (TP) had significantexponential relationships with the area percentages of forest, pond and paddy field. There existed a significantlinear relationship between the TP and PAP concentrations in stream water and the area percentages of forest,pond and paddy field, and the discharge of PAP was also significantly linearly correlated with the dischargeof suspended soil particles. There was a logarithmic linear relationship between DP and PAP discharges. Thestudy indicated that the adjustment of land use patterns and construction of ecologically sound landscapewould be an important measure to reduce the runoff discharge of phosphorus. The results would be veryuseful in building the best management practices (BMPs) of agricultural watershed in subtropics.

关键词： land use phosphorus runoff watershed

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Revegetation of Copper Mine Tailings with Ryegrass and Willow

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Pedosphere 2004年第3期14卷 283-288页

作者： HAOXiu-Zhen ZHOUDong-Mei SIYou-Bin statekeylaboratoryofsoilandsustainableagriculture InstituteofSoilScienceChineseAcademyofSciencesNanjing210008（China）

To restore vegetation on metal mine tailings is very difficult because theyoften contain high concentrations of heavy metals, low nutrient content and low water retentioncapacity. This study involved 3 experiments that evaluated the effects of 4 treatment amendments:montmorillonite, rice straw, organic manure and chemical fertilizer on the growth of ryegrass(Lolium perenne L.) and willow (Salix viminalis L.) with Cu and Zn mine tailings from two miningareas. The results showed that ryegrass was the most tolerant of 4 crops to Cu toxicity. Also whenorganic manure, which contained high concentrations of inorganic salts, was added to the minetailings, it significantly hindered ryegrass growth (P = 0.05). Meanwhile, with ryegrass organicmanure significantly increased (P = 0.05) the extractable Cu concentration in both mine *** montmorillonite was used as a mine tailings amendment with willow, the height and tress numberat the 1st cut were significantly greater (P = 0.05) than a control without montmorillonite. Howeverthere was no significant difference for height, tress number, dry weight or root dry weight at the2nd cut. So, amendment applications to reduce metal toxicity and increase nutrients retention inmine tailings were essential during revegetation of mine tailings.

关键词： amendment copper mine tailings ryegrass (lolium perenne L.) willow (salixviminalis L.) zinc mine tailings

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Nutrient Discharges from a Typical Watershed in the Hilly Area of Subtropical china

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Pedosphere 2003年第1期13卷 23-30页

作者： ZHANG GANLIN, YANG JINLING and ZHAO YUGUOinstitute of soil science, the chinese academy of sciences, nanjing 210008 (china) institute of soil science the Chinese Academy of Sciences Nanjing 210008 China

agriculture is still the biggest contributor of non-point source (NPS) pollution to water bodies andrunoff discharges of nutrients and other chemicals are one of the most important pathways. This studywas conducted during 1998～1999 in a typical watershed with complex agriculture and forestry systems aswell as dotted farmer villages, in a transitional region between the mid- and northern subtropical zones ofchina. Continuous sampling of stream water was performed regularly at a weekly frequency, with additionalsampling after all major rainfall events. The discharges of N and P nutrients and suspended materials weremeasured and the total and area-averaged annual discharges of all components were calculated. The resultsshowed an uneven seasonal distribution of nutrient discharges with summer storms contributing most tothe total fluxes. This study demonstrated a high dependence of runoff volume on rainfall but the overallrunoff coefficients were dependent on land use type and watershed size. The area-averaged annual dischargesvaried greatly among the sub-watersheds with different sizes and land use structures. This is the first studyestimating the area-averaged annual discharges of N and P in the hilly areas of subtropical china, which were1.5 g m-2 a-1 and 0.1 g m-2 a-1, respectively, providing important reference values for the assessment ofregional agricultural non-point source pollution.

关键词： discharge nutrients runoff subtropical china watershed

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Spatial Variation of P and N in Water and Sediments of Dianchi Lake, china

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Pedosphere 2005年第1期15卷 78-83页

作者： LUEJun-Jie, YANGHao GAOLi YUTian-Ying statekeylaboratoryofsoilandsustainableagriculture InstituteofSoilScienceChineseAcademyofSciencesNanjing210008China

Dianchi Lake is one of the most eutrophic lakes in china. In order to understand this eutrophication and to help control the pollution, this research investigated the spatial distribution of Kjeldahl nitrogen (K-N) and total phosphorus(TP) through analysis of bottom water and sediment (3 depths) samples collected at 118 sites around Dianchi Lake. The concentrations of K-N and TP for the lake bottom water in the Caohai part of the lake were much higher than those in the Waihai part, generally decreasing from north to south. In the sediments, the K-N concentration was higher in the Caohai part and the middle of the Waihai part. On the other hand, TP in the sediments was greater in the southern and western parts. Both K-N and TP had similar spatial distributions for the sediment samples of three different ***, the K-N and TP concentration in the sediments decreased with an increase in depth. This was evidence that eutrophication and pollution of Dianchi Lake was becoming gradually more severe. Exterior factors including uncontrolled input of domestic and industrial effluents as well as non-point pollution around the lake were the main reasons for serious eutrophication; therefore, controlling these was the first step in reducing eutrophication of Dianchi Lake.

关键词： nitrogen phosphorus sediments spatial distribution water

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Effect of Groundwater Irrigation on soil PAHs Pollution Abatement and soil Microbial Characteristics:A Case Study in Northeast china

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Pedosphere 2010年第5期20卷 557-567页

作者： ZHANG Jing ZHANG Hui-Wen ZHANG Cheng-Gang institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 (China) state key laboratory of soil and sustainable agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China)

To evaluate the effect of groundwater irrigation on the polycyclic aromatic hydrocarbons(PAHs) pollution abatement and soil microbial characteristics,a case study was performed in the Shenfu irrigation area of Shenyang,Northeast china,where the irrigation with petroleum wastewater had lasted for more than fifty years,and then groundwater irrigation instead of wastewater irrigation was applied due to the gradually serious PAHs pollution in *** chemical properties,including PAHs and nutrients contents,and soil microbial characteristics,including microbial biomass carbon,substrateinduced respiration,microbial quotient(qM),metabolic quotient(qCO2),dehydrogenase(DH),polyphenol oxidase(PO),urease(UR) and cellulase(CE) in surface and subsurface were *** organic C,total N,total P,and available K were significantly different between the sites *** PAHs concentrations ranged from 610.9 to 6362.8 μg kg-1 in the surface layers(0-20 cm) and from 404.6 to 4318.5 μg kg-1 in the subsurface layers(20-40 cm).From the principal component analysis,the first principal component was primarily weighed by total PAHs,total organic C,total N,total P and available K,and it was the main factor that influencing the soil microbial *** the tested microbial characteristics,DH,PO,UR,CE,qM and qCO2 were more sensitive to the PAHs stress than the others,thus they could serve as useful ecological assessment indicators for soil PAHs pollution.

关键词： microbial biomass paddy soil polycyclic aromatic hydrocarbons soil enzyme activities

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Cu and Zn Speciation in an Acid soil Amended withAlhalline Biosolids

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Pedosphere 2002年第2期12卷 165-170页

作者： LUO YONGMINGinstitute of soil science, the chinese academy of sciences, nanjing 210008 (china) institute of soil science the Chinese Academy of sciences Nanjing 210008

Fractionation of metals in acid sandy loam soil amended withalkaline-stabilised sewage sludge biosolids was conducted in order toassess metal bioavailability and environmental mobility. soilsolution was extracted by a centrifugation and filtration *** speciation in the soil solution was determined by a cationexchange resin method. Acetic acid and EDTA extracting solutions wereused for extraction of metals in soil solid surfaces. Metaldistribution in different fractions of soil solid phase wasdetermined using a three-step sequential extraction scheme.

关键词： alkaline-stabilised sewage sludge chemical speciation Cu granite soil

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