Dr. Brian Cumming arrives!
(Dr. Brian Cumming showing a sediment core from Lake Opinicon)
今天，高个子Cumming教授为我们带来了全新的课程——湖泊水体微生物调查。我们在船上度过了阳光灿烂的一天。 全体同学分为两组，交替在浅水区（littoral zone）和深水区（pelagic zone）取样调查。一开始，Cumming教授教我们认识水生植物，水下森林被长长的“钉耙”捞上水面，这些植物的名字形象极了，例如“coons tail”恰如毛绒绒的浣熊尾巴，“parrots feather”好似鹦鹉羽毛，斑马贻贝曾广泛附着在池杂草上，现在水质改善已经少了些，今天捞上的池杂草只有一株上面粘有斑马贻贝。还有螺旋形的水芹，释放的雄花白花花漂满水面。 今天的主要内容是学习使用各种仪器，这些设计巧妙，有各种稀奇古怪结构功能的取样仪器多以发明人名字命名，比如Eckcma，Schindler(不是电影里那个辛德勒哦)之类。许多仪器配有一个“秤砣”，将仪器放入水下，用绳子投放标记水深，到达指定位置放下“秤砣”，依靠重力打开机关，密封仪器取样。老师示范后每人都轮流试了一把，看着容易做起来就不一样了，少不了几次失败的尝试，不是机关提前打开就是没提出水面样品就漏了。
(Sampling from the barge.)
最奇妙的是Glow core，投下水后取出一米多深的一管湖底淤泥（表面还有一根蚊子幼虫），将收集管固定在专业工具上，每次0.25cm一点点向上推塞子，淤泥从上面溢出，一层层被收集到收集袋中就得到了不同深度的湖底淤泥样品。在晚上的讲座中我们还了解到湖底淤泥的不同层次还记录了历年的气候情况，就如树木年轮一般，是研究气候变化的调查手段之一。 收集了样本后，我们带着贴满标签的瓶瓶袋袋满载而归，回到实验室在显微镜下寻找湖水中的小生灵。微生物在显微镜下展现出它们及其对称的美丽身姿，对照彩色图鉴，我们一共认出30种微生物！
(Sedimate sampling on Lake Opinicon.)
Today, tall person Professor Cumming has brought the brand-new curriculum - - lake water body microorganism investigation for us. First time of this course, we spent the whole day on the boat and the lab. We have been divided into two groups, alternately (littoral zone) and the prefunded zone (pelagic zone). Each group need to take a sample the investigation in shallow water. From the very beginning, Professor Cumming taught us how to identify some common aquatic plants and some knowledge about aquatic environment. The submarine plants was scooped up by long “the toothed rake”, these plants is named basic on their appearance, for example “coons tail” has been as though the furry raccoon tail extremely, “parrots feather” seemed the parrot feather. Other common aquatic animal ,such as the zebra mussel, once widely adhered to stick cohere on the pond weed, with the help of organization and projects, the water quality has improved a lot. Today, the weed we scooped up the pond weed only attaches little zebra mussels. Because of such change of the water quality, we can see a plenty of the water salary’s flowers blooming under the water. Our primary coverage today was learning how to use each kind of instrument. The interesting thing is most of these instruments are named by their inventors, just like “Eckcma”, and “Schindler” (not the one in the movie). Many instruments have one “metal stuff”, puts in the instrument submarine, with the string delivery mark water depth, arrived assigns the position to lay down “the steelyard weight”. Then it depended upon the gravity to open the institution, sealed the instrument sample. After teacher demonstrated, each person in turn has tried, looked so easy but it was really hard to make it work. The most marvelous was Glow core, after throwing the sewer, it took out meter deep lake bottom silt (surface also to have a mosquito larva), fixed the collecting pipe on the specialized tool, each time 0.25cm little upwardly pushes the plug,
(Observing algae in the lab under the microscope.) the silt overflows from above, one was collected layer upon layer collects in the bag to obtain the different depth lake bottom silt sample. We also understood in evening's course the lake bottom silt of different level has also recorded all previous years’ weather condition, like the tree ring, studies one of climatic change investigation methods. After has collected the sample, we brought to paste a full bottle of bag to return home, back to the laboratory to seek for the small organism in the lake water under the microscope. With the help of the handbook, we altogether recognized 30 kinds of microorganisms!
P.S. Merlyn (in a shining pink T-shirt) has eaten five sausages today! But he still felt hungry…
(Under the scope.)