Rapid and Sensitive Microanalyzes of ^<13>C and ^<15>N tracers.

1.建立了气相色谱/燃烧/同位素比值质谱联用仪（GC/C/IRMS）。利用该系统建立了一种快速、简便的分析方法，用于测定湿地气泡甲烷的碳同位素比值、湖泊水样中溶解无机碳（SIGMACO_2）以及<13><13>水稻根际^ C-CH_4生成的^ C示踪研究.此外<15><13>，还开展了^ N_2和^ C示踪研究，以评估琵琶湖干土白蚁Neotermes koshuenies Shiraki的分子固氮作用和浮游植物的初级生产力。建立了生物材料制备的高真空实验装置，并对取自琵琶湖、Suwa、Teganuma和白蚁生态系统的各种生物样品进行了碳、氮同位素比值的测定.利用不同种类的浮游生物网和手工浸泡，成功地进行了水生微生物的粒度分级。

1. Gas chromatography/Combusion/Isotope Ratio Mass Spectrometer (GC/C/IRMS) was successfully established. The system was employed to develop a rapid and simple analytical methods for measuring carbon isotope ratio of bubble methane collected from wetlands, dissolved inorganic carbon (SIGMA CO_2) in lake water samples, and ^<13>C tracer studies of ^<13>C-CH_4 production from a rhizosphere of rice plants.2. ^<15>N_2 and ^<13>C tracer studies were also developed for assessing the molecular dinitrogen fixation by the dry-wod termite, Neotermes koshuenies Shiraki, and the primary production by phytoplankton in Lake Biwa.3. High vacuum line for the prepation of biological meterials were built and carbon and nitrogen isotope ratios were measured for various kinds of biogenic samples collected from L.Biwa, L.Suwa, L.Teganuma and a termite ecosystem.4. Size fractionation of aquatic microorganisms was successfully performed by using a various kind of plankton net and soating by hand.