Short-term e?ects of thinning, clear-cutting and stump harvesting on methane exchange in a boreal forest關(guān)于人類對北方森林的疏伐、濫砍濫伐和樹樁采伐對甲烷交換的短期影響 E. Sundqvist1, P. Vestin1, P. Crill2, T. Persson3, and A. Lindroth1 1Department of Physical Geography and Ecosystem Science, Lund University, Sweden 2Department of Geological Sciences, Stockholm University, Sweden 3Department of Ecology, Swedish University of Agricultural Sciences, Sweden 原文鏈接：http://www.biogeosciences-discuss.net/11/4637/2014/bgd-11-4637-2014.pdfShort-term e?ects of thinning, clear-cutting and stump harve12f9fc...
發(fā)布時(shí)間:
2015
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01
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05
瀏覽次數(shù)：42
In Situ Measurement of Dissolved Methane and Carbon Dioxide in Freshwater Ecosystems by Off-Axis Integrated Cavity Output Spectroscopy應(yīng)用LGR離軸積分腔輸出光譜技術(shù)原位測量淡水生態(tài)系統(tǒng)中的溶解甲烷和二氧化碳 Gonzalez-Valencia R1, Magana-Rodriguez F, Gerardo-Nieto O, Sepulveda-Jauregui A, Martinez-Cruz K, Anthony KW, Baer D, Thalasso F. AbstractA novel low-cost method for the combined, real-time, and in situ determination of dissolved methane and carbon dioxide concentrations in freshwater ecosystems was designed and developed. This method is based on the continuous sampling of water from a freshwater ecosystem to a gas...
發(fā)布時(shí)間:
2014
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12
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25
瀏覽次數(shù)：167
瑞士科學(xué)家應(yīng)用LGR快速甲烷分析儀在空中測量甲烷氣體排放 奶牛是最能代表瑞士的動(dòng)物，為這個(gè)國家生產(chǎn)奶酪，巧克力和牛奶，同時(shí)，也不斷排放一種溫室氣體：甲烷。甲烷對氣候變化的影響，是二氧化碳的20倍。現(xiàn)在，ABB旗下的LGR機(jī)載型快速甲烷分析儀為科學(xué)家們提供了可靠的工具來測量這一乳業(yè)副產(chǎn)品—甲烷。更多信息，請瀏覽：http://www.abb.com/cawp/seitp202/35E15CA4261E301BC1257D16003F6A08.aspx https://plus.google.com/102984631679721608539/posts/9dWxQEj3qEq
發(fā)布時(shí)間:
2014
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07
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23
瀏覽次數(shù)：67
NOAA使用LGR的CO分析儀來提高主要?dú)怏w的參考標(biāo)準(zhǔn)，之所以選用LGR CO分析儀，是因?yàn)樗兄叩臏?zhǔn)確性、精確度和線性相關(guān)度。詳情請?jiān)L問網(wǎng)址：http://www.wmo.int/pages/prog/arep/gaw/documents/CO_scale_X2014-notice.pdf或者查看如下附件： CO_scale_X2014-notice.pdfacc77c567b1f7446c11b5d76b0e55842.pdf (143.68 KB)
發(fā)布時(shí)間:
2014
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05
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29
瀏覽次數(shù)：69
Where does streamwater come from in low relief forested watersheds? A dual isotope approach探訪低起伏森林流域中溪水的來源 J. Klaus1,2, J. J. McDonnell2,3, C. R. Jackson4, E. Du5, and N. A. Griffiths6 1Centre de Recherche Public – Gabriel Lippmann, Department of Environment andAgro-biotechnologies, Belvaux, Luxembourg2Global Institute for Water Security, University of Saskatchewan, Saskatoon, SK, Canada3University of Aberdeen, School of Geosciences, Aberdeen, UK4Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, USA5Climate Science Department, Lawrence Ber...
發(fā)布時(shí)間:
2014
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03
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17
瀏覽次數(shù)：39
Approaches for Achieving Long-Term Accuracy and Precision of #18Oand #2H for Waters Analyzed using Laser Absorption Spectrometers應(yīng)用LGR液態(tài)水同位素分析儀長期測定#18O和#2H的準(zhǔn)確度和精度Leonard Irwin Wassenaar, Tyler Coplen, and Pradeep K. AggarwalEnviron. Sci. Technol., Just Accepted Manuscript ? Publication Date (Web): 16 Dec 2013Downloaded from http://pubs.acs.org on December 23, 2013 Approaches_for_Achieving_Long-Te rm_Accuracy_and_Precision_o209a5d42766de93abb6ff307d9ad4db5.pdf (800.18 KB)
發(fā)布時(shí)間:
2013
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12
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27
瀏覽次數(shù)：49
青海湖流域具鱗水柏枝植物水分利用氫同位素示蹤研究趙國琴1,2 李小雁1,2* 吳華武2 張思毅2 李廣泳21地表過程與資源生態(tài)國家重點(diǎn)實(shí)驗(yàn)室, 北京 100875; 2北京師范大學(xué)資源學(xué)院, 北京 100875 摘要 具鱗水柏枝(Myricaria squamosa)是我國高寒地區(qū)廣泛分布的優(yōu)勢河谷灌木, 具有維持河谷濕地系統(tǒng)穩(wěn)定的功能。然而, 目前國內(nèi)外有關(guān)具鱗水柏枝水分利用來源的定量研究很少。該文運(yùn)用氫穩(wěn)定同位素示蹤方法, 分析了青海湖流域具鱗水柏枝莖(木質(zhì)部)水和潛在水源(地下水、河水和土壤水)的氫穩(wěn)定同位素比率(δD)的季節(jié)變化, 發(fā)現(xiàn)具鱗水柏枝在不同水文環(huán)境下的植物水分利用來源有明顯差異。研究結(jié)果表明, 生長在河岸邊的具鱗水柏枝在6、7月主要利用地下水與河水, 分別占其所利用水分的89%、86%和55%、65%, 8月主要利用0–20 cm土層的土壤水, 9月水源不詳。生長在離河岸約100 m處的具鱗水柏枝在6月主要利用地下水與河水(91%、70%), 在7–9月以0–60 cm土層的土壤水為主要水源。這表明生長在河岸邊的具鱗水柏枝對地下水和河水的依賴程度較高, 而距離河岸約100 m時(shí)對土壤水的利用量較多, 反映出生長在不同生境中的具鱗水柏枝對特定水分條件的特殊適應(yīng)結(jié)果。關(guān)鍵詞 氘同位素, 具鱗水柏枝, 植物水分...
發(fā)布時(shí)間:
2013
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12
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16
瀏覽次數(shù)：48
植物葉片、莖稈和土壤水δ18O和δD是研究土壤-植被-大氣系統(tǒng)生態(tài)水文循環(huán)過程的重要示蹤劑。與傳統(tǒng)的穩(wěn)定同位素質(zhì)譜（IRMS）技術(shù)相比， 穩(wěn)定同位素紅外光譜（IRIS）技術(shù)具有測量速度快、運(yùn)行成本低等優(yōu)勢，將促進(jìn)穩(wěn)定同位素生態(tài)學(xué)的發(fā)展。利用低溫真空蒸餾抽提技術(shù)獲得的植物葉片和莖稈水中含有甲醇和乙醇類有機(jī)污染物，造成δ18O和δD的IRIS測量值偏離IRMS測量值（2.64±0.43）‰和（3.6±0.8）‰，超過了儀器精度。中國科學(xué)院地理科學(xué)與資源研究所的科研人員利用純水混入不同濃度的色譜純甲醇或乙醇，結(jié)合LGR公司生產(chǎn)的908-0008液態(tài)水同位素分析儀及光譜分析軟件確定甲醇（NB）和乙醇（BB）類物質(zhì)污染程度的光譜度量值， 建立了葉片莖稈水δ18O和δD的光譜污染校正方法。該研究成果將于近日發(fā)表在《中國生態(tài)農(nóng)業(yè)學(xué)報(bào)》第20卷第10期。 2012 紅外光譜測定葉片莖稈水18O和2H有機(jī)污染校正方法.pdf0db6094cf0b94390a2b7199c20ca8cdf.pdf (717.60 KB)
發(fā)布時(shí)間:
2012
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09
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11
瀏覽次數(shù)：55
David Bastviken, et al. Freshwater Methane Emissions Offset the Continental Carbon Sink.Science, 2011, 331(6013): 50 (doi:10.1126/science.1196808)A comerstone of our understanding of the contemporary global carbon cycle is that the terrestrial land surface is an important greenhouse gas (GHG) sink (1, 2). The global land sink is estimated to be 2.6 T 1.7 Pg of C year?1 (variability T range, excluding C emissions because of deforestation) (1). Lakes, impoundments, and rivers are parts of the terrestrial landscape, but they have not yet been included in the terrestrial GHG balance (3, 4). A...
發(fā)布時(shí)間:
2012
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02
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20
瀏覽次數(shù)：57
IAEA同位素水文研究組的2011年第29期實(shí)事通訊刊載文章，介紹使用LGR公司的水汽同位素分析儀（WVIA）和水汽同位素校準(zhǔn)源（WVISS）進(jìn)行水汽同位素的連續(xù)測量。Data Sets for Simultaneous Water Vapour and Rain Sampling Used in Modelling EffortsBy N.Kurita(IAEA)The Isotope Hydrology Section has been testing a newly available automated precipitation sampler to obtain short term isotopic data on precipitation and a laser spectroscopy analyzer for water vapour isotope analysis.IntroductionThe reliability of model based future climate scenarios described in the Intergovernmental Panel on Climate Change (IPCC) assessment report depends on how these models can simulate the ob...
發(fā)布時(shí)間:
2012
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02
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20
瀏覽次數(shù)：42