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Acta Geochimica 2017年第4期36卷 658-666页

作者： Faxiang Tao State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of Sciences99Lincheng West RoadGuanshanhu DistrictGuiyang 550081GuizhouChina

The carbon cycle of global inland waters is quantitatively comparable to other components in the global carbon budget. Among inland waters, a significant part is man-made lakes formed by damming rivers. Manmade lakes are undergoing a rapid increase in number and size. Human impacts and frequent algae blooms lead to it necessary to make a better constraint on their carbon cycles. Here, we make a primary estimation on the air–water co_2 transfer flux through an algae bloom year for a subtropical man-made lake—Hongfeng Lake, Southwest China. To do this a new type of glass bottles was designed for content and isotopic analysis of DIC and other environmental parameters. At the early stage of algae bloom,co_2 was transferred from the atmosphere to the lake with a net flux of 1.770 g·C·m^(-2). Later, the partial pressure(pco_2) of the aqueous co_2 increased rapidly and the lake outgassed to the atmosphere with a net flux of 95.727 g·C·m^(-2). In the remaining days, the lake again took up co_2 from the atmosphere with a net flux of 14.804 g·C·m^(-2). As a whole, Lake Hongfeng released 4527 t C to the atmosphere, accounting for one-third of the atmosphere/soil co_2 sequestered by chemical weathering in the whole drainage. With an empirical mode decomposition method, we found air temperature plays a major role in controlling water temperature, aqueous pco_2 and hence co_2 flux. This work indicates a necessity to make detailed and comprehensive carbon budgets in man-made lakes.

关键词： co2 flux Algae bloom Carbon cycle Inland waters Lake Hongfeng

Seasonal Variation and Meteorological control of co_2 flux in a Hilly Plantation in the Mountain Areas of North China

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Acta meteorologica Sinica 2011年第2期25卷 238-248页

作者：黄辉张劲松孟平伏玉玲郑宁高峻 Research Institute of Forestry CAFKey Laboratory of Tree Breeding and CultivationState Forestry Administration Institute of Geographic Sciences and Nature Resources Research CAS

The carbon cycle of terrestrial ecosystems is an important scientific issue in global climate change *** forest plays an important role in terrestrial carbon budget in *** this study,eddy covariance flux data measured at Xiaolangdi forest ecosystem research station（XLD） in 2007 and 2008 are used to analyze the seasonal variation and meteorological control of co2 flux in a 30-yr-old mixed *** plantation forest mainly consists of Quercus variabilis,Platycladus orientalis,and Robinia *** results show that the seasonal variations of net ecosystem exchange of co2（NEE）,gross primary production（GPP）,and ecosystem respiration（Re） display single-peak *** maximum of carbon sequestration appears during May and June each *** relative contribution of carbon release from ecosystem respiration to GPP varied slightly between 2007 and *** relationship between NEE and photosynthetic active radiation（Qp） accords with the rectangular hyperbola model on diurnal scale,and shows a good linear correlation on monthly *** ecosystem photosynthetic parameters：the maximum photosynthetic rate（Pmax）,the ecosystem photosynthetic photonyield（α）,and the daytime ecosystem respiration（Rd） exhibit seasonal *** reaches the maximum in August each year,with small interannual *** interannual differences of α and Rd are obvious,which is attributed to the changes of meteorological factors,such as solar radiation,vapor pressure deficit（D）,precipitation,*** Re,GPP,and NEP（net ecosystem production） have obvious exponential relations with temperature on monthly *** is a hysteresis in the response of GPP and NEP to temperature,i.e.,the carbon sequestration is not the maximum when the temperature reaches the peak *** Q10 values were 1.37 and 1.45 in 2007 and 2008,*** monthly scale,Re,GPP,and NEE increase as D increases,but rise slowly and even decrease when D is higher than 1.5 kPa.

关键词： hilly area of North China plantation eddy covariance co2 flux meteorological factors

Monitoring and simulation of water,heat,and co_2 fluxes in terrestrial ecosystems based on the APEIS-flux system

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Journal of Geographical Sciences 2005年第2期15卷 131-141页

作者： WATANABEMasataka WANGQinxue HAYASHISeiji MURAKAMIShogo LIUJiyuan OUYANGZhu LIYan LIYingnian WANGKelin NationalInstituteforEnvironmentalStudies Tsukuba305-8506Japan Inst.ofGeographicSciencesandNaturalResourcesResearch CASBeijing100101China XinjiangInstituteofEcologyandGeography CASUrumqi830011China NorthwestInstituteofPlateauBiology CASXining810008China InstituteofSubtropicalAgriculturalEcology CASChangsha410125China

The Integrated Environmental Monitoring (IEM) project, part of the Asia-Pacific Environmental Innovation Strategy (APEIS) project, developed an integrated environmental monitoring system that can be used to detect, monitor, and assess environmental disasters, degradation, and their impacts in the Asia-Pacific region. The system primarily employs data from the moderate resolution imaging spectrometer (MODIS) sensor on the Earth Observation System-(EOS-) Terra/Aqua satellite, as well as those from ground observations at five sites in different ecological systems in China. From the preliminary data analysis on both annual and daily variations of water, heat and co2 fluxes, we can confirm that this system basically has been working well. The results show that both latent flux and co2 flux are much greater in the crop field than those in the grassland and the saline desert, whereas the sensible heat flux shows the opposite trend. Different data products from MODIS have very different correspondence, e.g. MODIS-derived land surface temperature has a close correlation with measured ones, but LAI and NPP are quite different from ground measurements, which suggests that the algorithms used to process MODIS data need to be revised by using the local dataset. We are now using the APEIS-flux data to develop an integrated model, which can simulate the regional water, heat, and carbon fluxes. Finally, we are expected to use this model to develop more precise high-order MODIS products in Asia-Pacific region.

关键词： APEIS-flux system Asia-Pacific Environmental Innovation Strategy (APEIS) co2 flux Integrated Environmental Monitoring (IEM) MODIS water vapor flux

Satellite-derived surface water pco2 and air-sea co2 fluxes in the northern South China Sea in summer

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Progress in Natural Science:Materials International 2009年第6期19卷 775-779页

作者： Yu Zhu, Shaoling Shang, Weidong Zhai, Minhan Dai State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, China State Key Laboratory of Marine Environmental Science Xiamen University Xiamen 361005 China

An empirical approach is presented for the estimation of the partial pressure of carbon dioxide (pco2) and air-sea co2 fluxes in the northern South China Sea in summer using satellite-derived sea surface temperatures (SSTs), chlorophyll-a (Chl a) concentrations, and wind fields. Two algorithms were tested. The first used an SST-dependent equation, and the other involved the introduction of Chl a. Regression equations were developed for summer based on in situ data obtained in July, 2004. Using the monthly average SST and Chl a fields derived from the advanced very high resolution radiometer (AVHRR) and the SeaWiFS (sea-viewing wide field of view sensor), respectively, the monthly pco2 fields were computed. The derived pco2 was compared with the shipboard pco2 observations conducted in July, 2000. This resulted in a root-mean-square error of 4.6 latm, suggesting that the satellite-derived pco2 was in general agreement with the in situ observations. The air-sea co2 flux was further computed with the aid of the monthly mean QuikSCAT wind speed. We contend that more shipboard data are necessary for refining the empirical algorithms and reducing the uncertainty in the results.

关键词： pco2 Remote-sensing Northern South China Sea co2 flux

Carbon Dioxide concentration and flux in an Urban Residential Area in Seoul,Korea

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Advances in Atmospheric Sciences 2014年第5期31卷 1101-1112页

作者： Moon-Soo PARK Seung Jin JOO Soon-Ung PARK Weather Information Service Engine Center for Atmospheric Science & Earthquake ResearchSeoul 121-835 Korea Center for Atmospheric and Environmental Modeling Seoul 152-775 Korea

The carbon dioxide （co2） concentrations and fluxes measured at a height of 17.5 m above the ground by a sonic anemometer and an open-path gas analyzer at an urban residential site in Seoul, Korea from February 2011 to January 2012 were analyzed. The annual mean co2 concentration was found to be 750 mg m-3, with a maximum monthly mean concentration of 827 mg m-3 in January and a minimum value of 679 mg m-3 in August. Meanwhile, the annual mean co2 flux was found to be 0.45 mg m-2 s-1, with a maximum monthly mean flux of 0.91 mg m-2 s-1 in January and a minimum value of 0.19 mg m-2 s-1 in June. The hourly mean co2 concentration was found to show a significant diurnal variation; a maximum at 0700-0900 LST and a minimum at 1400-1600 LST, with a large diurnal range in winter and a small one in summer, mainly caused by diurnal changes in mixing height, co2 flux, and surface complexity. The hourly mean co2 flux was also found to show a significant diurnal variation, but it showed two maxima at 0700-0900 LST and 2100-2400 LST, and two minima at 1100-1500 LST and 0300-0500 LST, mainly caused by a diurnal pattern in co2 emissions and sinks from road traffic, domestic heating and cooking by liquefied natural gas use, and the different horizontal distribution of co2 sources and sinks near the site. Differential advection with respect to wind direction was also found to be a cause of diurnal variations in both the co2 concentration and flux.

关键词： co2 concentration co2 flux liquefied natural gas (LNG) Seoul urban residential area

The contribution of Nutrients and Water Properties to the Carbonate System in Three Particular Areas of the Tropical Atlantic (NE-BRAZIL)

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Journal of Geoscience and Environment Protection 2022年第2期10卷 135-161页

作者： Leonardo Bertini Elisabete de Santis Braga Oceanographic Institute University of S&#227 o Paulo S&#227 o Paulo Brazil

Tropical waters show different regional aspects due to specificities in their nutrient biogeochemical cycles, which can affect the carbon system and influence their regional role as sinks or sources of co2. This study was performed on particular tropical areas that present a different seasonal behaviour related to the carbon cycle observed in the late rainy season (July 2013). Understanding the co2 drawdown and outgassing potential in these areas is needed to call attention to more long-term monitoring efforts and protect understudied tropical coastal systems more efficiently. This study is focused on nutrient values, hydrological data, biogeochemical carbon behaviour linked to the carbonate system and includes estimates of co2 fluxes in three contrasting areas off the northeastern Brazilian shelf: 1) an urbanised estuary (Recife-REC), 2) a coastal Island (Itamaracá-ITA) and 3) an oceanic archipelago (Fernando de Noronha-FN). In general, REC acted as a source, while ITA and FN as carbon sinks. In ITA, despite the high DIC and Total Alkalinity observed (mean ~2360 μmol·kg-1), the sink is associated with an effective cascading of atmospheric co2 associated with turbulent shallow waters coupled with biogenic removal of and precipitation of Caco3 by coralline algae. FN acted as a sink, linked to minor decreases in Total Alkalinity (mean~2295 μmol·kg-1) influenced by ammonium-based primary production, nitrogen fixation and sporadic entrainment of nutrient rich waters in the upper thermocline. More studies in different western tropical Atlantic coastal systems can improve the knowledge of tropical shelf seas and their contribution to the ocean carbon budget under specific regional trophic regimes.

关键词： N/P/Si Ratios Total Alkalinity co2 flux Dissolved Inorganic Carbon Trophic conditions Western Tropical Atlantic

Soil co_2 Emissions as Affected by 20-Year continuous Cropping in Mollisols

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Journal of Integrative Agriculture 2014年第3期13卷 615-623页

作者： YOU Meng-yang YUAN Ya-ru LI Lu-jun XU Yan-li HAN Xiao-zeng Key Laboratory of Mollisols Agroecology Northeast Institute of Geography and AgroecologyChinese Academy of Sciences University of Chinese Academy of Sciences college of Geographical Science Harbin Normal University

Long-term continuous cropping of soybean （Glycine max）, spring wheat （Triticum aesativum） and maize （Zea mays） is widely practiced by local farmers in northeast China. A field experiment （started in 1991） was used to investigate the differences in soil carbon dioxide （co2） emissions under continuous cropping of the three major crops and to evaluate the relationships between co2 fluxes and soil temperature and moisture for Mollisols in northeast China. Soil co2 emissions were measured using a closed-chamber method during the growing season in 2011. No remarkable differences in soil organic carbon were found among the cropping systems （P〉0.05）. However, significant differences in co2 emissions from soils were observed among the three cropping systems （P〈0.05）. Over the course of the entire growing season, cumulative soil co2 emissions under different cropping systems were in the following order： continuous maize （（829±10） g co2 m2）〉continuous wheat （（629±22） g co2 m^2）〉continuous soybean （（474±30） g co2 m-2）. Soil temperature explained 42-65% of the seasonal variations in soil co2 flux, with a Q10 between 1.63 and 2.31; water-filled pore space explained 25-47% of the seasonal variations in soil co2 flux. A multiple regression model including both soil temperature （T, ~C） and water-filled pore space （W, %）, log（]）=a＋bT log（W）, was established, accounting for 51-66% of the seasonal variations in soil co2 flux. The results suggest that soil co2 emissions and their Q10 values under a continuous cropping system largely depend on crop types in Mollisols of Northeast China.

关键词： co2 flux monocultures soil organic carbon temperature sensitivity water-filled pore space