Some Quick Facts About Microbes Likely to be Seen on Microslides

 

        Some Quick Facts About Microbes Likely to be Seen on Microslides

          

          I. Bacteria

           

               These are the most abundant life form on this planet.

          Some biologists believe bacteria was the first life form.

          Bacteria defy classification as animal or plant and are usually 

          considered as part of the the kingdom Protista(stemming from

          the protozoans). Bacertia vary greatly in relative size but have 

          only three basic shapes...spherical(coccus), rod 

          shaped(bacillus), and corkscrewed or spiraled(spirilum).

          The largest bacteria ranges only 2 microns (unobservable on 

          normal lab microscopes found in wastewater plants).  Bacteria

          is the major food source in a process.  Protozoa are the 

          indicative groups that depict stages of bacterial growth. One

          reference suggests a statistical mean of about 100,000 bacteria 

          is found per milliliter of "fresh aerated" raw sewage.  In stale 

          sewage, the reference suggests an exponential increase...a million 

          or more. A further defined grouping of bacteria classifies them as 

          being part of a group called Monera (along with blue green 

          algae)...or functionally as lacking a nuclear membrane. 

          II. Protozoans

               Originally classifed under the animal kingdom, they are now 

          generally recognized as in a kingdom of their own called 

          Protists.  These are one celled organisms that use specialized 

          organelles(internal cell structures)for life functions.  The 

          following is a listing of the common groups and types seen under 

          the wastewater microslide.  The groups themselves are highly 

          recognizable while the various species requires some taxonomic 

          identification.  If time permits, seek a taxonomic identification 

          guide for individual identifications (see end for recommended 

          texts):

          1.  amoeba (Class Sardonia)

              a. two types...shelled and naked

                 1.)  arcella vulgaris(shelled)

                 2.)  difflugia (shelled)

                 3.)  dimastigamoeba (naked, classic)

                 4.)  nuclearia (naked)

          2.  Flagellated Protozoa (Class Mastigophora)

              a.  (zoomastigina)as the biocycle develops in the log growth 

                  bacterial stages, many low order flagellated types will 

                  develop that may require high power for observation.  It 

                  may be best to observe these as an overall activity. 

              b.  a more advanced stage in that log growth will show higher 

                  and larger forms of flagellates.  Some of these forms 

                  will be very recognizable.

                  1.)  euglena

                  2.)  peranema

                  3.)  pleuromonas

           3. Creeper Ciliates

              a.  "Creeper" is a convenient descriptive term that describes 

                  the next order of protozoa to develop on the biocycle.  

                  Creepers are more accurately part of the "Swimming 

                  Ciliate" groups...but do not show the high motility of the

                  later developing kinds.  These "creepers" in fact are some

                  of the larger and more definable protozoa to be seen under

                  the microslide.

                  1.)  Aspidisca

                  2.)  telotrochs

            4. Free Swimming Ciliates

              a.  There is an abundant number of free swimming ciliates.  

                  This grouping has a wide range when it appears on the 

                  biocycle, from moderate log growth stages to early 

                  endogenous stages.  These will be some of the largest

                  protozoa and as well the most active and motile.  Their

                  appearances and shapes are readily recognizable.

                  1.)  Paramecium (appears in log growth stages)

                  2.)  litonontus

                  3.)  Trachelophyllum

                  4.)  Colipidium

                  5.)  plagiiopyla

                  6.)  chilodonella

                  7.)  dileptus

                  8.)  trachelius

                  9.)  amphileptus

                 10.)  hemiophrys

                 11.)  poteriodendron 

            5. Stalked Ciliates

               a. The most definable characteristic of stalked ciliates is 

                  their classic bell shapes.  Nearly all stalked ciliates

                  will be seen as more or less stationary.  There some 

                  intermediate stages of some species of stalked ciliates

                  that are very mobile and do not show the classic 

                  structure.  A useful observation will be the appearance

                  of the stalks themselves...thier apparent relative 

                  thickness and length and as well if there are only single

                  bells or several or many bunched together.  

                  1.)  vorticella

                  2.)  carchesium

                  3.)  epistylis

                  4.)  campanella

                  5.)  opercularia (many branches, bunches)

                  6.)  vaginicola

         

          III.  Rotifers (phyllum Rotifera) 

              Rotifers of course will be one of the most advance types to be 

          found under the wastewater microslide.   These are one of the 

          first forms of life that have organ functions and are   

          Multicellular.  These are also very recognizable and will be one 

          of the larger organisms found in the microslide.

          

          The following is a listing of common Rotifers as they are found in 

          ascending order of common occurence:

          

             1. keratella cochlearis

             2. polyarthra vulgaris

             3. synchaeta pectinata

             4. brachionus quadridentata

             5. trichocerca iongiseta

             6. rotaria sp. 

             7. filinia longiseta

             8. kellicottia longispina

             9. pompholys sp. 

               

          IV.  Other types

          

          a. The commonly seen type a lot of operators call "water bear" is

             a multicellular animal, Aelosoma. very large.

          b. Perhaps the largest animal seen will be roundworms.  One of

             the most common is Chironomus and grow to stretch across 

             a slide and be visible with the naked eye.  These will be 

             segmented

          c. Nematodes will be smaller worms, pointy posterior and anterior

             usually unsegmented.

          d. Suctoria is a commonly seen microorganism that shows rigid 

             tenacles and a rigid stalk.  Shows on a wide range from early

             log growth to endogenous stages.

          e. typical fungii shapes will appear like tree twigs with branches

             and segmenting.

          f. water mites; very large; 

          g. crustaceans (not typically in mixed liquors but might be 

             observed in clarifier debri;)

         V.  Some interesting facts about Pathogens

             Thoughout history, water has been the prime mode of transimssion

          of desease.  One of the first extensive attempts to control this

          mode was the building of the famous aqueducts by the ancient 

          Romans.  It was perhaps one of the corner stones of modern 

          civilization to be able to control wastewater to prevent vast 

          outbreaks of sickness.  The most common deseases that were once 

          killers (and still remain to be so again if not controlled) are

          typhoid fever, dysentary, and diptheria.  The common bacteria     

          pathogens that caused these deseases are Salmonella Typhosa, Shigella 

          Dysenteriae, and Vibrio Comma.  It is a tribute to what our field 

          accomplishes to realize that these deseases are virutally non-

          existent in our society...and need only to look as far as

          underdeveloped countries and see the high incidence of these 

          deseases where wastewater is not controlled well.  It was not 

          until recently that wastewater control has directed its 

          attentions not only toward health and desease prevention, but 

          also to the effects it has on our environment. 

          

              Viruses however still remain a concern even in developed 

          countries due to their small size that makes them hard to 

          detect.  There still remains extremely low occurances of any

          outbreak of desease even due to viruses. 

          

               Instead of performing analysis on wastewater for specific 

          kinds of pathogens, a group of non-pathogens is used as a very 

          accurate indicator of the likelihood of pathogen presence...or 

          non-presence.  These are of course the coliforms...and include 

          the genera Escherichia and Aerobacter.  These are generally 

          accepted as originating in the intestines of warm blooded 

          animals (some occur naturally in soil however). Escherichia Coli 

          is considered as originating solely from fecal matter.  This 

          establishes some of the reasoning as to why total coliform groups 

          are tested for in water quality while Escherichia Coli is tested 

          for specifically for pollution influence on a water...and thusly 

          we see the highly specific test for "Fecal Coliform" (which 

          relates mostly to E. Coli) at exact temperature and nutrient 

          inducement and the more general testing for "Total Coliform" 

          (some of which may originate from soil and would not be Fecal) in 

          water quality testing.  

          ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ 

               This is not meant as an indepth study of wastewater 

          taxoconomy but is simply a short overview of types that can be 

          seen under the typical wastewater microslide.  In depth studies 

          are of course only beneficial.  But toward the end of process 

          control, the objective again is to discern the relative trends a 

          plant's process is moving.  For this objective, such microslide 

          observations should be functional first and foremost and the study 

          made of relative groups and their general robustness rather than 

          specific types and their actual numbers.  Differentiation of 

          different species can add insight however and narrow the relative 

          conditions for which a certain flora is thriving.  

               The following manual is reccomended to have on hand for 

          reference.  The formal microbiologist's attack is of course an 

          ideal the operator should know as much about as possible (as found 

          in this manual)

          "MICROSCOPIC ANALYSIS OF ACTIVATE SLUDGE-TRAINING MANUAL".

          EPA-430/1-80-007. NATIONAL TRAINING AND OPERATIONAL TECHNOLOGY 

          CENTER, CINCINNATI, OH 45268.