Section outline

    • The concentrated sample is also stored in the refrigerator to shield from light. At the time of samples microscopic examination, the sample is gently stirred and a fixed volume (about 2 mL) is collected with a pipette. It is placed on a glass slide for phytoplankton counting, which has a mesh pattern on the bottom (Fig. 6).

      計数用スライドグラス

      Fig. 6 Glass slides for counting

    • The glass slides for phytoplankton counting have a frame that can hold a 2 mL sample, into which the concentrated sample is pipetted.

      A cover glass that fits this large frame is also commercially available.

      When the sample is inserted between the glass slide frame and the cover glass, and the cover glass begins to float, capillary action causes the cover glass to rotate so that it fits over the glass slide frame (Figs. 7 and 8).

      計数用スライドグラスにカバーグラスを載せる

      Fig. 7. Placing a cover glass on a counting glass slide

      カバーグラスを載せる

      Fig. 8. Placing a cover glass

      Counting algae on a plankton counting plate

      1. Injecting algae

      *Take care not to float the cover glass or introduce air bubbles.

      The cover will close naturally.

      2. Allow to stand for a while

      *To allow algae to settle and improve counting accuracy.