Screening of methyl chloride emitting plants in the sub-tropics and a study on the controlling factors of methyl chloride emission.

（1）筛选甲基氯酰氯启动植物，在订购时找到甲基氯酰氯启动植物，我们从一个植物中取出一个或多个叶子，并在几天后测量的甲基氯酰氯集中。在伊利奥特岛收集了两种100和14种亚热带植物物种。Thirty-two species among them were found to emit methyl chloride with average emManagement rate of 0.11 ~ 0.51/g·（g dry wt）^\-1>·hr^\-1\。（2）伊里奥特岛大气层甲基氯化钠的测量结果在8月和2月共收集了5个站点，并对甲基氯化钠进行了分析。最高集中度， 2750 ppt，在一个森林网站上观看。在沿海网站收集的样本中， 40 - 50 ppt在上游样本和下游样本之间找到了差异，并建议在热带森林覆盖的岛屿上的运输过程中收集甲基氯化物。根据风的速度和估计的混合高度，从森林中提取甲基氯化钠的排放率计算为5 - 100微克·m^<-2>·h^<-1>，将相应地从整个岛屿中提取10 - 250公吨的年度总排放量。（3）因子影响植物中的甲基氯化物发射率从热带树中的甲基氯化物发射率，费恩斯使用袋子封闭方法进行了调查。Cyateha lepifera在发射率上展示了一个午夜的下降，而Cyateha podophyla则展示了一个午夜的最大限度。However，两个Ferns在中午使用动态质量平衡室进行实验时，在他们的甲基氯酰氯发射。增加的环境温度增强了来自Cyatha podophylla的甲基氯化物发射，但来自Cyateha lepifera的发射受到了抑制。

(1)Screening of methyl chloride emitting plantsIn order to find methyl chloride emitting plants, we put one or multiple leaves detached from a plant into a 40 ml-vial, and measured methyl chloride concentration in it after a few days. Two hundred and fourteen species of subtropical plants were collected in Iriomote Island. Thirty-two species among them were found to emit methyl chloride with average emission rate of 0.11〜0.51μg・(g dry wt)^<-1>・hr^<-1>.(2)Measurements of atmospheric methyl chloride in Iriomote IslandAir samples were collected at 5 sites in August and at 6 sites in February, and were analyzed for methyl chloride. Highest concentration, 2750 ppt, was observed at a forestal site. In the samples collected at coastal sites, 40〜50 ppt difference was found between the upwind sample and the downwind sample, suggesting accumulation of methyl chloride during the transport over the island covered by tropical forests. Based on the wind velocity and assumed mixing height, the emission rate of methyl chloride from the forest was calculated to be 5〜100μg・m^<-2>・h^<-1>, which would correspond to annual total emission of 10〜250 metric ton from the whole island.(3)Factors affecting methyl chloride emission from plantsFoliar emission rates of methyl chloride from tropical tree ferns were investigated using a bag enclosure method. Cyateha lepifera showed a midday decline in emission rates, whereas Cyathea podophyla showed a midday maximum. However, both of the ferns had a midday minimum in their methyl chloride emission in the experiment using a dynamic mass balance chamber. Increased ambient temperature enhanced methyl chloride emission from Cyathea podophylla, but suppressed the emission from Cyateha lepifera.