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working with samples from mud and sand
AIM - To illustrate the types of organisms that are likely to be encountered in sediments, how those organisms are collected, how they are observed, documented, and the documentation placed into micro*scope. In addition the exercise addressed isolation (by picking), and moving organisms into culture.
This exercise may stretch over several days. It is used to explore many aspects of working with material from nature. Throughout, we need images of people conducting the various procedures, and these can be added to Protistiary.
COLLECT
Collect samples of mud using the tray method  or from sand using the Uhlig method - a variant of which is appropriate if you wish to target dinoflagellates . You can also collect from submerged mud . At the same time, collect at least 100 mls of local water for making media.
DOCUMENTING ORGANISMS FROM MUDS AND SANDS USING LIGHT MICROSCOPY
 Observe under the dissecting scope. You should be able to discriminate some major types - such as diatoms, dinoflagellates, ciliates, amoebae and so on. Targeting one type, select cells and start developing a photographic record. Restrict the photograpohic sessions to an hour or so. But then work up the images in readiness to put on the web , and when you think they are ready, we can assess them and then move them into micro*scope . You will also need at least a generic name for the organism, so also be ready to invest time in identification.
DOCUMENTING ORGANISMS FROM MUDS AND SANDS USING SCANNING ELECTRON MICROSCOPY (optional)
Both diatoms and dinoflagellates look very well when imaged by scanning electron microscopy (SEM). If these organisms are abundant in samples, we may carry out some scanning electron microscopy. Protocols for dinoflagellates are available, but if the work involves diatoms or other organisms, new protocols should be written.
DOCUMENTING SMALLER ORGANISMS FROM THE SITES
Place 20 mls of unfiltered water in flasks with a couple of rice grains. Leave for several days, observe any material that is flocculent, identify and document.
AND AFTER THEY HAVE BEEN DOCUMENTED
Work the images up and move them into micro*scope
CULTURES
No protocols are available for cultures as yet. There are two options. The first is to pick cells of one type, transfer them into depression dishes in medium made up in 0.2 µm filtered water, check daily for purity and growth, and when growing should be moved into larger dishes. The second is to add about 2 mls of crude sample to 20 mls of medium made up in 0.2 µm filtered water, check after a day or so, and isolate cells that have survived the process. Often only a few species of weeds survive, and will form a good basis for cultures.
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