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Effects of land use, climate, topography and soil properties on regional soil organic carbon and total nitrogen in the Upstream Watershed of Miyun Reservoir, North China

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Journal of Environmental Sciences 2012年第3期24卷 387-395页

作者： Shufang wang xiaoke wang Zhiyun Ouyang State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Soil organic carbon （SOC） and total nitrogen （TN） contents as well as their relationships with site characteristics are of profound importance in assessing current regional, continental and global soil C and N stocks and potentials for C sequestration and N conservation to offset anthropogenic emissions of greenhouse gases. This study investigated contents and distribution of SOC and TN under different land uses, and the quantitative relationships between SOC or TN and site characteristics in the Upstream Watershed of Miyun Reservoir, North China. Overall, both SOC and TN contents in natural secondary forests and grasslands were much higher than in plantations and croplands. Land use alone explained 37.2% and 38.4% of variations in SOC and TN contents, respectively. The optimal models for SOC and TN, achieved by multiple regression analysis combined with principal component analysis （PCA） to remove the multicollinearity among site variables, showed that elevation, slope, soil clay and water contents were the most significant factors controlling SOC and TN contents, jointly explaining 70.3% of SOC and 67.1% of TN contents variability. Only does additional 1.9% and 3% increase in the interpretations of SOC and TN contents variability respectively when land use was added to regressions, probably due to environment factors determine land use. Therefore, environmental variables were more important for SOC and TN variability than land use in the study area, and should be taken into consideration in properly evaluating effects of future land use changes on SOC and TN on a regional scale.

关键词： soil organic carbon soil total nitrogen principal component analysis multiple regression analysis

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Structure and function of rhizosphere and non-rhizosphere soil microbial community respond differently to elevated ozone in field-planted wheat

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Journal of Environmental Sciences 2015年第6期27卷 126-134页

作者： Zhan Chen xiaoke wang He Shang Institute of Forest Ecology Environment and Protection Chinese Academy of Forestry Key Laboratory of Forest Ecology and EnvironmentState Forestry Administration State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

To assess the responses of the soil microbial community to chronic ozone（O3）, wheat seedlings（Triticum aestivum Linn.） were planted in the field and exposed to elevated O3（e O3）concentration. Three treatments were employed：（1） Control treatment（CK）, AOT40 = 0;（2） O3-1, AOT40 = 1.59 ppm·h;（3） O3-2, AOT40 = 9.17 ppm·h. Soil samples were collected for the assessment of microbial biomass C, community-level physiological profiles（CLPPs）, and phospholipid fatty acids（PLFAs）. EO3 concentration significantly reduced soil microbial carbon and changed microbial CLPPs in rhizosphere soil, but not in non-rhizosphere *** results of the PLFAs showed that e O3 concentrations had significant effects on soil community structure in both rhizosphere and non-rhizosphere soils. The relative abundances of fungal and actinomycetous indicator PLFAs decreased in both rhizosphere and non-rhizosphere soils, while those of bacterial PLFAs increased. Thus the results proved that e O3 concentration significantly changed the soil microbial community function and composition, which would influence the soil nutrient supply and carbon dynamics under O3 exposure.

关键词： O3 Wheat Rhizosphere soil Non-rhizosphere soil CLPP PLFA

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Arbuscular mycorrhizal fungi alter the response of growth and nutrient uptake of snap bean(Phaseolus vulgaris L.) to O_3

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Journal of Environmental Sciences 2011年第6期23卷 968-974页

作者： Shuguang wang Zhaozhong Feng xiaoke wang Wenliang Gong Department of Environmental Science and Engineering Beijing University of Chemical Technology Beijing 100029 China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Beijing Urban Ecosystem Research Station Beijing 100085 China

The effects of arbuscular mycorrhizal fungi（AMF） Glomus mosseae on the responses to elevated O3 in growth and nutrition of snap bean（Phaseolus vulgaris *** Guangzhouyuan） were *** was conducted in growth chambers by using three O3 concentrations（20（CF）,80（CFO1） and 120 nL/L（CFO2）;8 hr/day for 75 days）.Results showed that elevated O3 slightly impacted overall mycorrhizal colonization,but significantly decreased the proportional frequency of hypha and increased the proportional frequency of spores and vesicles,suggesting that O3 had significant effects on mycorrhizal *** O3 significantly decreased yield,dry mass and nutrient contents（N,P,K,Ca and Mg） in both non-mycorrhizal and mycorrhizal ***,significant interactive effects were found in most variables due to that the reduction by O3 in the mycorrhizal plants was less than that in the non-mycorrhizal ***,AMF increased the concentrations of N,P,Ca,and Mg in shoot and *** can be concluded that AMF alleviated detrimental effects of increasing O3 on host plant through improving plant nutrition and growth.

关键词： arbuscular mycorrhizal fungi nutrition status mycorrhizal colonization elevated 03 snap bean

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Effects of Drought on Net Primary Productivity:Roles of Temperature,Drought Intensity,and Duration

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Chinese Geographical Science 2016年第2期26卷 270-282页

作者： SUN Binfeng ZHAO Hong wang xiaoke Jinan Environmental Research Institute Jinan 250100China State Key Laboratory of Urban and Regional Ecology ResearchCenter for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Joint Center for Global Change Studies(JCGCS) Beijing 100875China

Northeast China has experienced frequent droughts over the past fifteen years. However, the effects of droughts on net primary productivity(NPP) in Northeast China remain unclear. In this paper, the droughts that occurred in Northeast China between 1999 and 2013 were identified using the Standardized Precipitation Evapotranspiration Index(SPEI). The NPP standardized anomaly index(NPP-SAI) was used to evaluate NPP anomalies. The years of 1999, 2000, 2001, and 2007 were further investigated in order to explore the influence of droughts on NPP at different time scales(3, 6, and 12 months). Based on the NPP-SAI of normal areas, we found droughts overall decreased NPP by 112.06 Tg C between 1999 and 2013. Lower temperatures at the beginning of the growing season could cause declines in NPP by shortening the length of the growing season. Mild drought or short-term drought with higher temperatures might increase NPP, and weak intensity droughts intensified the lag effects of droughts on NPP.

关键词： drought net primary productivity(NPP) Standardized Precipitation Evapotranspiration Index(SPEI) NPP Standardized anomaly index(NPP-SAI)

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Multi-attribute-Based Access Control Policy for Supply Chain Data Service

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Chinese Journal of Electronics 2018年第6期27卷 1283-1290页

作者： ZOU Junwei LAN Jiewei wang xiaoke LUO Hong School of Electronic Engineering Beijing University of Posts and Telecommunications School of Computer Science Beijing University of Posts and Telecommunications School of Information and Communication Engineering Beijing University of Posts and Telecommunications

The Electronic product code(EPC) network is established and maintained in worldwide-scale based on the EPC standard framework to guarantee the real-time information recognition, and provide efficient management for supply chain. In EPC network, a series of data services can be provided due to the requirements of users. Aiming to guarantee the security of data services, we propose a dynamic access control model for data services based on multiple attributes. We extract specific attribute sets from user, and calculate security level of user using certainty and uncertainty theories based on the attribute sets. The data can be provided to users according to the security level of user and data. The security of data in the supply chain can be guaranteed, and data acquisition can be dynamic and fine-grained. We deploy the proposed model to real supply chain management system we built to verify effectiveness and feasibility of the solution.

关键词： EPCglobal Supply chain Data service Access control

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Ambient air quality trends and driving factor analysis in Beijing, 1983–2007

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Journal of Environmental Sciences 2011年第12期23卷 2019-2028页

作者： Ju Zhang Zhiyun Ouyang Hong Miao xiaoke wang State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The rapid development in Beijing, the capital of China, has resulted in serious air pollution problems. Meanwhile great efforts have been made to improve the air quality, especially since 1998. The variation in air quality under the interaction of pollution and control in this mega city has attracted much attention. We analyzed the changes in ambient air quality in Beijing since the 1980’s using the Daniel trend test based on data from long-term monitoring stations. The results showed that different pollutants displayed three trends： a decreasing trend, an increasing trend and a flat trend. SO2, dustfall, B[a]P, NO2 and PM10 fit decreasing trend pattern, while NOx showed an increasing trend, and CO, ozone pollution, total suspended particulate （TSP）, as well as Pb fit the flat trend. The cause of the general air pollution in Beijing has changed from being predominantly related to coal burning to mixed traffic exhaust and coal burning related pollution. Seasonally, the pollution level is typically higher during the heating season from November to the following March. The interaction between pollution sources change and implementation of air pollution control measures was the main driving factor that caused the variation in air quality. Changes of industrial structure and improved energy effciency, the use of clean energy and preferred use of clean coal, reduction in pollution sources, and implementation of advanced environmental standards have all contributed to the reduction in air pollution, particularly since 1998.

关键词： ambient air quality trend analysis driving factor particulate matter

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Response of runoff and soil loss to reforestation and rainfall type in red soil region of southern China

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Journal of Environmental Sciences 2010年第11期22卷 1765-1773页

作者： Zhigang Huang Zhiyun Ouyang Fengrui Li Hua Zheng xiaoke wang Department of Ecology & Agriculture Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China. State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

To evaluate the long-term effects of reforestation types on soil erosion on degraded land, vegetation and soil properties under conventional sloping farmland （CSF） and three different reforestation types including a Pinus massoniana secondary forest （PSF）, an Eucommia ulmoides artificial economic forest （EEF） and a natural succession type forest （NST）, were investigated at runoff plot scale over a six-year period in a red soil region of southern China. One hundred and thirty erosive rainfall events generating runoff in plots were grouped into four rainfall types by means of K-mean clustering method. Erosive rainfall type I is the dominant rainfall type. The amount of runoff and the soil loss under erosive rainfall type III were the most, followed by rain-fall type II, IV and I. Compared with CSF treatment, reforestation treatments decreased the average annual runoff depth and the soil loss by 25.5%–61.8% and 93.9%– 96.2% during the study period respectively. Meanwhile, runoff depth at PSF and EEF treatments was significantly lower than that in NST treatment, but no significant difference existed in soil erosion modulus among the three reforestation treatments. This is mainly due to the improved vegetation properties （i.e., vegetation coverage, biomass of above- and below-ground and litter-fall mass） and soil properties （i.e., bulk density, total porosity, infiltration rate and organic carbon content） in the three reforestation treatments compared to CSF treatment. The PSF and EEF are recommended as the preferred reforestation types to control runoff and soil erosion in the red soil region of southern China, with the NST potentially being used as an important supplement.

关键词： reforestation type rainfall type vegetation and soil property soil erosion red soil region

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Transpiration rates of urban trees, Aesculus chinensis

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Journal of Environmental Sciences 2012年第7期24卷 1278-1287页

作者： Hua wang xiaoke wang Ping Zhao Hua Zheng Yufen Ren Fuyuan Gao Zhiyun Ouyang State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Institute of Forestry and Pomology Beijing Academy of Agriculture and Forestry SciencesBeijing 100093China South China Institute of Botany Chinese Academy of SciencesGuangzhou 510650China Beijing Teaching Botanical Garden Beijing 100061China

Transpiration patterns of Aesculus chinensis in relation to explanatory variables in the microclimatic, air quality, and biological phenomena categories were measured in Beijing, China using the thermal dissipation method. The highest transpiration rate measured as the sap flux density of the trees took place from 10：00 am to 13：00 pm in the summer and the lowest was found during nighttime in the winter. To sort out co-linearity, principal component analysis and variation and hierarchical partitioning methods were employed in data analyses. The evaporative demand index （EDI） consisting of air temperature, soil temperature, total radiation, vapor pressure deficit, and atmospheric ozone （O3）, explained 68% and 80% of the hourly and daily variations of the tree transpiration, respectively. The independent and joint effects of EDI variables together with a three-variable joint effect exerted the greatest influences on the variance of transpiration rates. The independent effects of leaf area index and atmospheric 03 and their combined effect exhibited minor yet significant influences on tree transpiration rates.

关键词： horse chestnut sap flux density microclimate air pollutants leaf area index

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Carbon budgets of three temperate forest ecosystems in Dongling Mt.,Beijing,China

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Science China Earth Sciences 2007年第1期50卷 92-101页

作者： FANG JingYun LIU GuoHua ZHU Biao wang xiaoke LIU ShaoHui Department of Ecology College of Environmental Sciences and Key Laboratoryfor Earth Surface Processes of the Ministry of Education Peking University Beijing 100871 China

There is a general agreement that forest ecosystems in the NorthernHemisphere function as significant sinks for atmospheric CO_2; however, their magnitude anddistribution remain large uncertainties. In this paper, we report the carbon (C) stock and itschange of vegetation, forest floor detritus, and mineral soil, annual net biomass increment andlitterfall production, and respiration of vegetation and soils between 1992 to 1994, for threetemperate forest ecosystems, birch (Betula platyphylla) forest, oak (Ouercus liaotungensis) forestand pine (Pinus tabulaeformis) plantation in Mt. Dongling, Beijing, China. We then evaluate the Cbudgets of these forest ecosystems. Our results indicated that total C density (organic C perhectare) of these forests ranged from 250 to 300 t C ha^(-1), of which 35—54 t C ha^(-1) fromvegetation biomass C and 209-244 t C ha^(-1) from soil organic C (1 m depth, including forest floordetritus). Biomass C of all three forests showed a net increase, with 1.33—3.55 t C ha^(-1) a^(-1)during the study period. Litterfall production, vegetation autotrophic respiration, and soilheterotrophic respiration were estimated at 1.63—2.34,2.19—6.93, and 1.81 —3.49 t C ha^(-1)a^(-1), respectively. Ecosystem gross primary production fluctuated between 5.39 and 12.82 t Cha^(-1) a^(-1), about half of which (46%-59%, 3.20-5.89 t C ha^(-1) a^(-1)) was converted to netprimary production. Our results suggested that pine forest fixed C of 4.08 t ha^(-1) a^(-1), whereassecondary forests (birch and oak forest) were nearly in balance in CO_2 exchange between theatmosphere and ecosystems.

关键词： carbon budget carbon density carbon flux mountainous area temperate forest.

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Effects of elevated ozone on growth and yield of field-grown rice in Yangtze River Delta,China

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Journal of Environmental Sciences 2008年第3期20卷 320-325页

作者： CHEN Zhan wang xiaoke FENG Zhaozhong ZHENG Feixiang DUAN Xiaonan YANG Wenrui Research Center for Eco-Environmental Sciences Chinese Academy of Scienees Beijing 100085 China

With rapid industrialization and urbanization in the Yangtze Delta, China, the tropospheric ozone concentration has increased to levels that induce crop yield loss. Rice, a widely grown crop in China, was investigated in field-established, open-top chambers. Four treatments were used： charcoal-filtered air （CF）, non-charcoal-filtered air （NF）, and charcoal-filtered air with two levels of additional ozone （O3-1 and O3-2）. The AOT40s （accumulated hourly mean ozone concentration above 40 ppbv） were 0, 0.91, 23.24, and 39.28 ppmv.h for treatment of CE NF, O3-1, and O3-2, respectively. The rice height and biomass were reduced in the elevated ozone concentration. Less organic matter partitioning to roots under the elevated ozone significantly decreased rice root activity. The yield loss was 14.3% and 20.2% under O3-1 and O3-2 exposure, respectively. This was largely caused by a reduction in grain weight per panicle.

关键词： ozone rice growth yield Yangtze Delta

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