Sampling methodology of micro and macro algae

1. Unit II
VBT315

2. Introduction
 Algae sampling is a crucial process in environmental
monitoring and research, particularly in aquatic
ecosystems.
 The methodology for algae sampling can vary
depending on the specific goals of the study, the type
of water body, and the characteristics of the algae
being studied.

3. Field Sampling
Depending on the study, field sampling can involve
different methods:
 Water Sampling: Collect water samples at various
depths using a sampler. This is important for analyzing
nutrient levels and other water quality parameters.
 Kick Sampling: For benthic algae, kick the substrate
to dislodge attached algae, and collect samples
downstream with a net.
 Plankton Net Tows: Use a plankton net to collect
phytoplankton from the water column.

4. Preservation
 Preserve collected samples using appropriate
preservatives (e.g., Lugol's solution for
phytoplankton).
 This helps maintain the integrity of the samples for
later analysis.

5. Phytoplankton Sampling
 Integrated Water Sampling:
 Collect water samples at various depths using a water sampler
(such as a Van Dorn or Niskin bottle) to capture
phytoplankton from different water layers.
 Secchi Disk Depth:
 Measure water transparency using a Secchi disk. This
information can help assess light availability, which is crucial
for phytoplankton growth.
 Plankton Net Tows:
 Use a plankton net with a fine mesh to collect phytoplankton
from the water column. Tow the net at various depths to
obtain a representative sample.
 Vertical Hauls:
 Lower a plankton net to specific depths and then vertically
haul it to the surface. This method helps capture
phytoplankton at different depths.

6. Periphyton and Attached Algae Sampling
 Kick Sampling:
 Kick the substrate (e.g., rocks, sediment) to dislodge
periphyton and attached algae. Collect the dislodged
material downstream using a net.
 Scraping or Brushing:
 Use brushes or scrapers to collect periphytic algae from
surfaces such as rocks or submerged vegetation.
 Artificial Substrates:
 Deploy artificial substrates (e.g., glass slides, tiles) in the
water for a specific period. Collect and analyze the
attached algae that develop on these substrates.

7. Benthic Algae Sampling
 Grab Sampling:
 Use a sediment grab sampler to collect samples of the
benthic substrate. Benthic algae are often associated
with the bottom sediments.
 Core Sampling:
 Take sediment cores using a tube or corer to capture
both the sediment and the benthic algae associated with
it.
 Quadrat Sampling:
 Place a quadrat frame on the substrate and identify and
quantify the benthic algae within the defined area.

14. Microscopic Examination and
Identification
 Microscopy:
 Use microscopy to identify and count algae species. This
involves preparing slides from the collected samples and
examining them under a microscope.
 Cell Counting:
 Use a counting chamber to quantify the abundance of algae
cells in a known volume of the sample. This is crucial for
estimating cell density.

15. Molecular Techniques
 DNA Analysis:
 Conduct DNA analysis, such as DNA barcoding or next-
generation sequencing, to identify algae species at a
molecular level. This is especially useful for studying
microbial and phytoplankton communities.
 PCR (Polymerase Chain Reaction):
 Use PCR to amplify specific DNA regions for targeted
identification of algae species.

16. THANK YOU