What are methods used for sampling zooplankton?
Three general classes of sampling gear are used to sample zooplankton, namely water bottles, pumps, and nets. This section will devote a major emphasis on net samplers, since they are most efficient for capturing organisms larger than micro-zooplankton.
Should we be sampling zooplankton at night?
Sampling zooplankton in the pelagic zone of lakes during the day is standard practice in limnology. We compiled 870 paired night-day zooplankton samples from the literature and found that crustacean zoo- plankton had, on average, 255% and 125% greater density and biomass, respectively, at night compared to day.
How do you count zooplankton?
2 Zooplankton may be measured by use of a calibrated eyepiece micrometer or camera lucida/tablet system during the identification and enumeration process, or they may be removed from the sample, photographed with a digital camera, and measurements calculated from the images.
How is a plankton sample collected?
Phytoplankton samples can be taken directly from the water at permanent observation stations or from ships. Sampling devices include hoses and flasks to collect water samples, and sometimes, plankton are collected on filters dragged through the water behind a ship. The water may turn greenish, reddish, or brownish.
How is zooplankton biomass measured?
Measurements of quantity NM VAN E The preferred measure of zooplankton biomass would be the total amount of 200- plankton under a unit area of sea surface, such as 1.0 m2 or 10.0 m, expressed in terms of organic content (i, ea weight of dry organic substances).
What is zooplankton biomass?
Zooplankton biomass can be calculated from the zooplankton weight (e.g. wet mass, dry mass or carbon mass), or zooplankton biovolume (e.g. displacement volume, settled volume).
How do you test for zooplankton?
To identify zooplankton requires use of a compound microscope. A dissecting microscope is also handy for sorting and counting. Specimens are mounted on glass slides and examined at 25-100X magnification.
What are different plankton sizes?
Size groups
| Group | Size range (ESD) |
|---|---|
| Megaplankton | > 20 cm |
| Macroplankton | 2→20 cm |
| Mesoplankton | 0.2→20 mm |
| Microplankton | 20→200 µm |
What can we learn from zooplankton samples?
The zooplankton samples are analyzed for estimation of biomass (standing stock), enumeration of common taxa and their species. Data obtained is utilized for computation of productivity and faunal and species biodiversity of the study area or ecosystem. Materials:
What are zooplankton monitoring instrument packages?
These instrument packages allow accurate depth directed net sampling of zooplankton, while at the same time measuring other important physical and biological parameters when zooplankton are collected.
What sampling rates are available for plankton and water samples?
User-selectable plankton and water sampling rates between 1 and 60 min are available, whilst depth and flow data can be logged at intervals ranging from 1 s to 60 rnin. Gulf Ill OCEAN sampler This type of sampler uses a carousel containing a number of nets that rotate and take sequential samples.
What obstructions should be avoided when sampling zooplankton?
Any obstruction in front of the net mouth may lead to avoidance of the sampler by the larger forms of zooplankton and may also create problems in recording an accurate water flow through the net (Tranter 1968). It is recommended that nets without frontal obstructions be used when sampling larger forms of mesozooplankton (> 5mm).