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Uncertainty analysis of CO_2 flux components in subtropical evergreen coniferous plantation

Science China Earth Sciences 2009年第2期52卷 257-268页

作者： LIU Min1,2,3, HE HongLin1, YU GuiRui1, LUO YiQi4, SUN XiaoMin1 & WANG HuiMin1 1 Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China 2 Gradute School of the Chinese Academy of Sciences, Beijing 100049, China 3 School of Geography Science, Nanjing Normal university, Nanjing 210097, China 4 department of botany and microbiology, university.of oklahoma, 770 Van Vleet Oval, norman, ok 73019, usa Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Gradute School of the Chinese Academy of Sciences Beijing China School of Geography Science Nanjing Normal University Nanjing China department of botany and microbiology University of Oklahoma Norman USA

We present an uncertainty analysis of ecological process parameters and CO2 flux components (Reco, NEE and gross ecosystem exchange (GEE)) derived from 3 years’ continuous eddy covariance meas-urements of CO2 fluxes at subtropical evergreen coniferous plantation, Qianyanzhou of ChinaFlux. Daily-differencing approach was used to analyze the random error of CO2 fluxes measurements and bootstrapping method was used to quantify the uncertainties of three CO2 flux components. In addition, we evaluated different models and optimization methods in influencing estimation of key parameters and CO2 flux components. The results show that: (1) Random flux error more closely follows a dou-ble-exponential (Laplace), rather than a normal (Gaussian) distribution. (2) Different optimization meth-ods result in different estimates of model parameters. Uncertainties of parameters estimated by the maximum likelihood estimation (MLE) are lower than those derived from ordinary least square method (OLS). (3) The differences between simulated Reco, NEE and GEE derived from MLE and those derived from OLS are 12.18% (176 g C·m-2·a-1), 34.33% (79 g C·m-2·a-1) and 5.4% (92 g C·m-2·a-1). However, for a given parameter optimization method, a temperature-dependent model (T_model) and the models derived from a temperature and water-dependent model (TW_model) are 1.31% (17.8 g C·m-2·a-1), 2.1% (5.7 g C·m-2·a-1), and 0.26% (4.3 g C·m-2·a-1), respectively, which suggested that the optimization methods are more important than the ecological models in influencing uncertainty in estimated carbon fluxes. (4) The relative uncertainty of CO2 flux derived from OLS is higher than that from MLE, and the uncertainty is related to timescale, that is, the larger the timescale, the smaller the uncertainty. The relative uncertainties of Reco, NEE and GEE are 4%-8%, 7%-22% and 2%-4% respectively at annual timescale.

关键词： CO2 flux components statistical uncertainty analysis bootstrapping method subtropical evergreen coniferous plantation Qianyanzhou

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Spatial patterns of ecosystem carbon residence time in Chinese forests

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中国科学：地球科学英文版 2010年第8期53卷 1229-1240页

作者： ZHOU Tao1,2, SHI PeiJun1,2, JIA GenSuo3, LI XiuJuan1,2 & LUO YiQi4 1 State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal university, Beijing 100875, China 2 Academy of Disaster Reduction and Emergency Management, Ministry of Civil Affairs & Ministry of Education, Beijing 100875, China 3 Key Laboratory of Regional Climate-Environment Research for Temperate East Asia, Chinese Academy of Sciences, Beijing 100029, China 4 department of botany and microbiology, university.of oklahoma, norman, ok 73019, usa State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing China Academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs & Ministry of Education Beijing China Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Chinese Academy of Sciences Beijing China department of botany and microbiology University of Oklahoma Norman USA

Capacity of carbon sequestration in forest ecosystem largely depends on the trend of net primary production (NPP) and the length of ecosystem carbon residence time. Retrieving spatial patterns of ecosystem carbon residence time is important and necessary for accurately predicting regional carbon cycles in the future. In this study, a data-model fusion method that combined a process-based regional carbon model (TECO-R) with various ground-based ecosystem observations (NPP, biomass, and soil organic carbon) and auxiliary data sets (NDVI, meteorological data, and maps of vegetation and soil texture) was applied to estimate spatial patterns of ecosystem carbon residence time in Chinese forests at steady state. In the data-model fusion, the genetic algorithm was used to estimate the optimal model parameters related with the ecosystem carbon residence time by minimizing total deviation between modeled and observed values. The results indicated that data-model fusion technology could effectively retrieve model parameters and simulate carbon cycling processes for Chinese forest ecosystems. The estimated carbon residence times were highly heterogenous over China, with most of regions having values between 24 and 70 years. The deciduous needleleaf forest and the evergreen needleleaf forest had the highest averaged carbon residence times (73.8 and 71.3 years, respectively), the mixed forest and the deciduous broadleaf forest had moderate values (38.1 and 37.3 years, respectively), and the evergreen broadleaf forest had the lowest value (31.7 years). The averaged carbon residence time of forest ecosystems in China was 57.8 years.

关键词： carbon residence time carbon cycle forest ecosystem data-model fusion inverse modeling genetic algorithm

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GeoChip:Recent Development,and its Applications to Bioenergy and Global Change Biology

GeoChip:Recent Development,and its Applications to Bioenergy...

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2008年中国微生物学会学术年会

作者： Jizhong Zhou Institute for Environmental Genomics and department of botany and microbiology,university.of oklahoma,norman,ok

Microarray technology provides the opportunity to identify thousands of microbial genes or populations simultaneously.A comprehensive functional gene array(GeoChip) was developed to detect and monitor microbial communities important to various biogeochemical,ecological and environmental *** on the second generation of GeoChip,a new generation,GeoChip 3.0,has been developed,which has several new ***,GeoChip 3.0 contains～25,000 Drobes and covers～47,000 sequences for 292 gene ***,the homology of

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Geochemical characterization of aromatic hydrocarbons in crude oils from the Tarim,Qaidam and Turpan Basins,NW China

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Petroleum Science 2010年第4期7卷 448-457页

作者： Zhang Min Paul Philp department of Geochemistry Yangtze University Jingzhou Hubei 434023 China The Key Laboratory of Oil ＆ Gas Resources and Exploration Technology Ministry of Education Yangtze University Jingzhou Hubei 434023 China School of Geology and Geophysics University of Oklahoma Norman OK 73019 USA

Based on the systematic study of aromatic hydrocarbons in over 100 crude oil samples collected from the Tabei and Tazhong uplifts in the Tarim Basin,the western depression area in the Qaidam Basin and the Tabei depression in the Turpan Basin,the geochemical characteristics of the marine（Tarim Basin）,saline lacustrine（Qaidam Basin）,and swamp（Turpan Basin） oils were *** marine oils from the Tarim basin are characterized by relatively low abundance of diaromatic hydrocarbons such as biphenyl and naphthalene,and relatively high abundance of triaromatic hydrocarbons including phenanthrene,dibenzothiophene and *** contrast,the swamp oils from the Turpan Basin are dominated by the highest relative abundance of diaromatic hydrocarbons and the lowest relative abundance of triaromatic hydrocarbons in all the oil samples in this *** relative abundance of diaromatic and triaromatic hydrocarbons in the saline lacustrine oils from Qaidam Basin is between that in Tarim oils and Turpan *** parameters based on the isomer distributions of dimethylnaphthalenes（DMN）,trimethylnaphthalenes（TMN）,tetramethylnaphthalenes（TeMN） and methylphenanthrenes（MP）,i.e.,1,2,5-trimethylnaphthalene（TMN）/1,3,6-TMN ratio,1,2,7-TMN/1,3,7TMN ratio,（2,6-＋2,7-）-dimethylnaphthalenes（DMN）/1,6-DMN ratio,1,3,7-TMN/（1,2,5-＋1,3,7-）TMN,1,3,6,7-TeMN/（1,3,6,7-＋1,2,5,6-＋1,2,3,5-）-TeMN ratio and MP index,may reflect the diversity of organic source input,thermal maturity and depositional *** addition,the dibenzothiophenes（DBTs）/fluorenes（Fs） and dibenzofurans（DBFs）/Fs ratios were found to the very useful and effective in determining genetic types of crude oils for the marine,saline lacustrine,and swamp depositional environments,and for oil-oil correlations.

关键词： China Tarim Basin Qaidam Basin Turpan Basin marine oil saline lacustrine oil coal-derived oil depositional environment aromatic hydrocarbons

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Bioamendment of petroleum contaminated ultisol:effect on oil content, heavy metals and pH of tropical soil

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Journal of Environmental Sciences 2001年第1期13卷 92-98页

作者： E. D. Udosen 1, J. P. Essien 2, R. M. Ubom 2 (1 department of Chemistry and Biochemistry, university.of Uyo, Nigeria 2 department of botany and microbiology, university.of Uyo, Nigeria) department of Chemistry and Biochemistry University of Uyo Nigeria

The effect of organic amendments on the oil content, heavy metals concentration and pH of petroleum contaminated sandy loam ultisol obtained from Rumuekpe oil field in Emohua Local Government Area of Rivers State, Nigeria was determined. Petroleum contaminated soils were treated with wood ash, compost and sawdust. The addition of organic amendments resulted in a significant(at 95% probability level) decrease in oil content by 92% for composting, 81% for soil treated with sawdust and 58% for soil with ash supplementation, over 6 months. The effect of treatments on the iron(Fe), copper(Cu) and lead(Pb) concentration was significant at P <0 001. The remediation also affected the pH of soil. This initial pH of 5 6 was depressed by the application of compost and sawdust supplements respectively to a final pH of 5 2 and 5 3. On the other hand, amending the soil with wood ash raised the pH from 5 6 to 6 2. Increased acidity caused a decrease in the heavy metals concentration in the contaminated soil. Soil treatment with compost generally gave the best remediation results, followed by sawdust and then ash. Adjusting the pH of oil contaminated soil to high acidic levels may promote the availability and migration of heavy metals in remediated soils and not necessarily the rate of oil mineralization.

关键词： bioamendament tropical soil Nige

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A NEW "TETRASPORANGIAL" SPECIES OF LIAGORA (RHODOPHYTA, NEMALIALES) FROM HAWAI'I

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Chinese Journal of Oceanology and Limnology 1995年第4期13卷 343-347页

作者： Isabella A. Abbott(department of botany, university.of Hawai’i, Honolulu, Hawai’i 96822 usa) department of botany University of Hawai\'i Honolulu Hawaii 96822 USA

A new species of Liagora, L. perennis sp. nov. from Hawai'i, is described. Unlike species of this genus in China, it is carpotetrasporangial, and at the place of expected carposporangia bears cruciately di-vided tetrasporangia, a detail which differentiates it from the usual species of Liagora without tetraspores that have been reported in China. Notes are provided on other Liagora species that have an impact on the taxonony of species found in China.

关键词： Liagora perennis tetrasporangia

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Studies on the chemical constituents of the South China Sea sponge Phacellia fusca

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Chinese Journal of Chemistry 1991年第2期9卷 136-143页

作者： ZENG,Long-Mei FU,Xiong SU,Jing-Yu department of Chemistry,Zhongshan university,Guangzhou 510275De GUZMAN,Florecita SCHMITZ,Francis J HOSSAIN,M.Bilayet van der HELM,Dick department of Chemistry and Biochemistry,university.of oklahoma,norman,ok73019-0370,U.S.A. department of Chemistry Zhongshan University Guangzhou 510275 department of Chemistry and Biochemistry University of Oklahoma Norman OK 73019–0370 U.S.A.

Three pyrrololactam alkaloids have been isolated from the marine sponge Phacellia fusca Schmidt collected from the South China Sea,and their structures were determined as 1—3,on the grounds of spectral *** is the fir... 详细信息

关键词： Studies on the chemical constituents of the South China Sea sponge Phacellia fusca

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A NEW SESTERTERPENE FROM THE SPONGE PHYLLOSPONGIA FOLIASCENS

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Chinese Chemical Letters 1991年第7期2卷 543-544页

作者： Xiong FU Long Mei ZENG Jing Yu SU Chemistry department,Zhongshan university,Guangzhou,510275Francis J.SCHMITZ department of Chemistry,university.of oklahoma,norman,oklahoma 73019—0370,U.S.A.

Phylloketal(1),a new sesterterpene which belongs to the scalarane class of sesterterpene.s with a 20,24- bishomo—tetracyclic skeleton,has been isolated from the South China Sea sponge Phyllospongia foliascens,and its... 详细信息

关键词： ppm A NEW SESTERTERPENE FROM THE SPONGE PHYLLOSPONGIA FOLIASCENS Reports

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Spatial patterns in temperature sensitivity of soil respiration in China: Estimation with inverse modeling

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Science China(Life Sciences) 2009年第10期52卷 982-989页

作者： ZHOU Tao1,2, SHI PeiJun1,2, HUI DaFeng3 & LUO YiQi4 1 State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal university, Beijing 100875, China 2 Academy of Disaster Reduction and Emergency Management, Ministry of Civil Affairs & Ministry of Education, Beijing 100875, China 3 department of Biological Sciences, Tennessee State university, Nashville, TN 37209, usa 4 department of botany and microbiology, university.of oklahoma, norman, ok 73019, usa State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 Chin

Temperature sensitivity of soil respiration (Q10) is an important parameter in modeling the effects of global warming on ecosystem carbon release. Experimental studies of soil respiration have ubiquitously indicated that Q10 has high spatial heterogeneity. However, most biogeochemical models still use a constant Q10 in projecting future climate change and no spatial pattern of Q10 values at large scales has been derived. In this study, we conducted an inverse modeling analysis to retrieve the spatial pattern of Q10 in China at 8 km spatial resolution by assimilating data of soil organic carbon into a proc-ess-based terrestrial carbon model (CASA model). The results indicate that the optimized Q10 values are spatially heterogeneous and consistent to the values derived from soil respiration observations. The mean Q10 values of different soil types range from 1.09 to 2.38, with the highest value in volcanic soil, and the lowest value in cold brown calcic soil. The spatial pattern of Q10 is related to environmental factors, especially precipitation and top soil organic carbon content. This study demonstrates that inverse modeling is a useful tool in deriving the spatial pattern of Q10 at large scales, with which being incorporated into biogeochemical models, uncertainty in the projection of future carbon dynamics could be potentially reduced.

关键词： temperature sensitivity Q10 soil respiration global warming inverse analysis

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Phosphorus availability in two soils amended with poultry litter

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Journal of Environmental Sciences 1996年第4期8卷 483-490页

作者： Han Xingguo (Institute of botany,Chinese Academy of Sciences,Beijing 100093,China)Duane C.Wolf (department of Agronomy,university.of Arkansas,Fayetteville, AR 72701,usa) Institute of botany Chinese Academy of Sciences Beijing 100093 China department of Agronomy University of Arkansas Fayetteville AR 72701 United States

Understanding P transformation in soils amended with poultry litter is important if water quality is to be *** objectives were to determine the influence of method of litter application and temperature on P availability. Poultry litter containing 20. 8g P/kg (dry weight) was either surface-applied or incorporated into Captina (fine-silty, siliceous, mesic Typic Fragiudult) and Nixa (loamy-skeletal,siliceous,Glossic Fragiudult) silt loams at rates of 0 or 10g/kg and incubated at 20℃ or 35℃ at a water potential of -40 kpa. Water soluble and available P (0.03 mol/L NH4F+0. 025mol/L HCl extraction) were determined during a 60d laboratory study. Results indicated that water soluble and available P levels in the soils initially decreased, then rapidly increased,and approached a steady state phase after approximately 20d. After 60d, water soluble P levels were significantly higher when litter was surface applied than when litter was incor porated. When the incubation was terminated, the net increase in available P in both soils was>100 mg P/*** efficient recycling of P and protection of water quality, application method and temperature should be considered when amending soils with poultry litter,

关键词： nutrient cycling phosphorus availability poultry litter water quality.

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