With the support of the Faculty of Sea-Derivative Sciences at the Istanbul University , the task is to take water samples by using specific scientific instruments, to record the oxygen, salinity and heat levels and to illustrate planktons’ samples on pre-determined stations and depths indicated on the map along the track of ship’s course. The illustrations of Chlorophyll- a samples are to be kept in the deep-freezer and other plankton samples are to be kept in pots, and the measurements taken at the place of activity are to be recorded by the data on that particular day, hour and place. After completing the illustrative stage of the research, the study is to be focused on counting the planktons and analysis of chlorophyll-a.
The Measurement of Oxygen, Salinity, pH and Heat
The density of oxygen, salinity, pH and heat in the sea are very important factors having an effect on the variety and the density of planktons. The changes in these parameters determine the living spaces of the planktons. Further, any change in these parameters means the change in the species of the planktons’ living in that corresponding region. Therefore, the results of the measurements are very important to interpret the dispersion of plankton species.
The Plankton Research
The Plankton is the name given to all the organisms which live independently in the sea; although they have organs for drifting, but they swim weakly; and they float passively by water movements. The word Plankton originated from the Greek word Planktons which means drifting, floating and moving by the water movements. The plankton in the sea occupies a significant place among the species in the nature due to the characteristics of their habitat. It is possible to come across planktons all over the hydrosphere covering ¾ part of the earth and having an average depth between 3800mts to 9000mts. No other living species has such a wide range of living spaces like planktons do.
Planktons, according to the organisms’ biological characteristics, are divided into two groups called phytoplankton and zooplankton. Phytoplankton (vegetable plankton) is the organism so-called autotroph which has the ability to synthesize their own nutrition with the help of photosynthesis; zooplankton (animal plankton) is the organism so-called hetetroph which feed themselves with organic particle and organism where they live. When the phytoplankton is thought of together with zooplankton regarding their food chain, they supply their own foodstuffs by forming a closed food cycle. Furthermore, they make up a group of living species which have the ability to survive without any kind of dependency upon any other organisms. The production of phytoplankton depends especially on the balance between phyto-zooplankton and their production speed. The zooplankton whose major foodstuff is phytoplankton flocks to the places where phytoplankton populated much.
Plank tonic organisms do not only supply their own foodstuff, but they also supply other animals’ direct or indirect food needs. Fishes like sardines and anchovies feed on planktons. These fishes collect planktons by filtering them through their gills. With regard to their food value, plank tonic organisms play a very important role. Zooplankton, particularly krustaceler consists of important amino acids and plausibly all type of minerals. Phytoplankton is on the other hand is rich in vitamin-C content.
The nutritious elements like silica, nitrogen and phosphorus are founded in the sea water in various forms and these elements form the first step of material circulation in the sea eco-system. Therefore nutritious element in one environment affects directly the first and later productions in this environment. At the first glance phytoplankton forms and other seaworthy plants as well constitute the first circle in the food chain. Ammonium, nitrate and inorganic phosphate in the sea water are to be assimilated by the plants and transformed into organic material which is a utility for other sea animals.
Plank tonic species and populations can be moved from one place to another or much farther places via sea currents. Thus population and density of the plankton in many environments show diversity. Further, light, heat and oxygen are the important factors regarding the dispersion of plankton populations. As a conclusion, the stock amount of both various fish species in one region and benthic organisms shows diversity parallel to the dispersion of plank tonic organisms.
Material & Methods
Plankton Sampling: In Zooplankton sampling, a scoop net full of plankton is dragged vertically from a depth of 50 meters . The Unesco WP-2 model of scoop net with cell diameter of 200 mm is to be used during the sampling. The scoop net is composed of a conic edge with a diameter of 57 cm and a length of 2 ,61 m , and a bag fabricated from nytal nylon with a cell diameter 200 mm . Further at the end of the bag section where filtered plankton is to be collected, there are two PVC made collectors having two openings each covering the same cell structured surface given above. In the process of counting zooplankton samples, 3*1 ml samples are to be taken out from sampling pet via stemple pipet, then the counting and identification are to be done with stereo binocular microscope in the zooplankton counting chamber. Bigger and hard to be found species like sagitta are to be analyzed at full sample and their biomass is to be extracts from their soaked weight. Rose (1938), Tregoboff and Rose (1957) are the references for a systematical identification of species. The collected samples of planktons are mixed with fermaldehit solution having 4% borax application so that the zooplanktons are to be kept without any deformation. Then the samples are kept in 250 cc plastic pets for future references.
The calculation of the abundance and biomass of individuals:
a=c/b b=Wt/v v=3.14.r2.h
c=the number of subjects
h= the range of the depth the plankton is derived (m)
v= volume of the filtered water (m³)
r= The radius of the conic edge of the scoop net (m)
Wt= total wet weight (mg)
The measurement of Chlorophyll- a is to be carried out by Nusch (1980) method.
The measurement of oxygen, salinity, PH and heat, which is done via pIONeer 65 model multi parameter and W-A.T.C and manual refract meter.
The clarity and color is to be determined by Forhel Scale and 25 cm Sechi Disk.
Water Sampling: Water sample is taken at each 10 meters until 50 meter at every pre-determined station in Nansen water sampling bottles of 2 liters , and the samples are to be measured.
The Result of the Research
The result of research and comparative tables are to be published in the periodicals of the Istanbul University , Faculty of Sea-Derivative Sciences. The water quality, fish populations and the variety of species of the East Mediterranean Sea are also to be interpreted with this study.
Prof. Dr. Ahmet Nuri Tarkan, the professor of Sea Biology at the Istanbul University , Faculty of Sea-Derivative Sciences, supervises this research.