Short-term effects of thinning, clear-cutting and stump harvesting on methane exchange in a boreal forest关于人类对北方森林的疏伐、滥砍滥伐和树桩采伐对甲烷交换的短期影响 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原文链接：http://www.biogeosciences-discuss.net/11/4637/2014/bgd-11-4637-2014.pdf
发布时间:
2015
-
01
-
05
浏览次数：53
Short-term effects of thinning, clear-cutting and stump harvesting on methane exchange in a boreal forest关于人类对北方森林的疏伐、滥砍滥伐和树桩采伐对甲烷交换的短期影响 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 原文链接：http://www.biogeosciences-discuss.net/11/4637/2014/bgd-11-4637-2014.pdfShort-term effects of thinning, clear-cutting and stump harve12f9fc...
发布时间:
2015
-
01
-
05
浏览次数：42
In Situ Measurement of Dissolved Methane and Carbon Dioxide in Freshwater Ecosystems by Off-Axis Integrated Cavity Output Spectroscopy应用LGR离轴积分腔输出光谱技术原位测量淡水生态系统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...
发布时间:
2014
-
12
-
25
浏览次数：149
瑞士科学家应用LGR快速甲烷分析仪在空中测量甲烷气体排放 奶牛是最能代表瑞士的动物，为这个国家生产奶酪，巧克力和牛奶，同时，也不断排放一种温室气体：甲烷。甲烷对气候变化的影响，是二氧化碳的20倍。现在，ABB旗下的LGR机载型快速甲烷分析仪为科学家们提供了可靠的工具来测量这一乳业副产品—甲烷。更多信息，请浏览：http://www.abb.com/cawp/seitp202/35E15CA4261E301BC1257D16003F6A08.aspx https://plus.google.com/102984631679721608539/posts/9dWxQEj3qEq
发布时间:
2014
-
07
-
23
浏览次数：67
NOAA使用LGR的CO分析仪来提高主要气体的参考标准，之所以选用LGR CO分析仪，是因为它有着更高的准确性、精确度和线性相关度。详情请访问网址：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)
发布时间:
2014
-
05
-
29
浏览次数：69
Where does streamwater come from in low relief forested watersheds? A dual isotope approach探访低起伏森林流域中溪水的来源 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...
发布时间:
2014
-
03
-
17
浏览次数：31
Approaches for Achieving Long-Term Accuracy and Precision of #18Oand #2H for Waters Analyzed using Laser Absorption Spectrometers应用LGR液态水同位素分析仪长期测定#18O和#2H的准确度和精度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)
发布时间:
2013
-
12
-
27
浏览次数：49
青海湖流域具鳞水柏枝植物水分利用氢同位素示踪研究赵国琴1,2 李小雁1,2* 吴华武2 张思毅2 李广泳21地表过程与资源生态国家重点实验室, 北京 100875; 2北京师范大学资源学院, 北京 100875 摘要 具鳞水柏枝(Myricaria squamosa)是我国高寒地区广泛分布的优势河谷灌木, 具有维持河谷湿地系统稳定的功能。然而, 目前国内外有关具鳞水柏枝水分利用来源的定量研究很少。该文运用氢稳定同位素示踪方法, 分析了青海湖流域具鳞水柏枝茎(木质部)水和潜在水源(地下水、河水和土壤水)的氢稳定同位素比率(δD)的季节变化, 发现具鳞水柏枝在不同水文环境下的植物水分利用来源有明显差异。研究结果表明, 生长在河岸边的具鳞水柏枝在6、7月主要利用地下水与河水, 分别占其所利用水分的89%、86%和55%、65%, 8月主要利用0–20 cm土层的土壤水, 9月水源不详。生长在离河岸约100 m处的具鳞水柏枝在6月主要利用地下水与河水(91%、70%), 在7–9月以0–60 cm土层的土壤水为主要水源。这表明生长在河岸边的具鳞水柏枝对地下水和河水的依赖程度较高, 而距离河岸约100 m时对土壤水的利用量较多, 反映出生长在不同生境中的具鳞水柏枝对特定水分条件的特殊适应结果。关键词 氘同位素, 具鳞水柏枝, 植物水分...
发布时间:
2013
-
12
-
16
浏览次数：43
植物叶片、茎秆和土壤水δ18O和δD是研究土壤-植被-大气系统生态水文循环过程的重要示踪剂。与传统的稳定同位素质谱（IRMS）技术相比， 稳定同位素红外光谱（IRIS）技术具有测量速度快、运行成本低等优势，将促进稳定同位素生态学的发展。利用低温真空蒸馏抽提技术获得的植物叶片和茎秆水中含有甲醇和乙醇类有机污染物，造成δ18O和δD的IRIS测量值偏离IRMS测量值（2.64±0.43）‰和（3.6±0.8）‰，超过了仪器精度。中国科学院地理科学与资源研究所的科研人员利用纯水混入不同浓度的色谱纯甲醇或乙醇，结合LGR公司生产的908-0008液态水同位素分析仪及光谱分析软件确定甲醇（NB）和乙醇（BB）类物质污染程度的光谱度量值， 建立了叶片茎秆水δ18O和δD的光谱污染校正方法。该研究成果将于近日发表在《中国生态农业学报》第20卷第10期。 2012 红外光谱测定叶片茎秆水18O和2H有机污染校正方法.pdf0db6094cf0b94390a2b7199c20ca8cdf.pdf (717.60 KB)
发布时间:
2012
-
09
-
11
浏览次数：53
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...
发布时间:
2012
-
02
-
20
浏览次数：51