SU1677625A1 - Method for selecting species-monitors among brown and red macrophytic algae accumulating maximum amount of heavy metals for the purposes of sea water pollution control - Google Patents

Description

The invention relates to environmental protection and can be used in the organization of monitoring of heavy metals in the coastal zone of the seas.

An assessment of the contamination of the aquatic environment by the level of contaminants in the tissues of aquatic organisms presents a number of advantages over direct chemical analysis of water. These advantages are both of a technical nature (there is no need to concentrate large volumes of water due to low concentrations of the detected compounds, since organisms perform the concentrating function) and the degree of informativeness of the results obtained (the level of contaminant in water can fluctuate and to obtain. the average estimate requires multiple-fold sampling, while hydrobionts are able to integrate in time small fluctuations in the concentration of substances in the medium). In addition, when determining contaminants in hydrobionts, the question of their bioavailability is solved, which remains open when analyzing water samples, suspended matter and bottom sediments.

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The prospect of macroalgae as indicator organisms or monitors for controlling the level of heavy metals in the marine environment has been repeatedly noted in the scientific sector. They meet these basic requirements set forth for

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monitor organisms, such as global distribution, mass distribution within the area, accessibility for collecting samples, residency, high concentrating ability for heavy metals. However, for the practical use of macrophytes for monitoring purposes, the main problem is the selection of species that are most suitable for each specific region.

In the seas of the USSR, the number of macroalgae species approaches 1000. If the range of objects is narrowed by limiting the depth of habitat (availability for collection without the use of special equipment), mass and prevalence (comparison of data from different stations), the number of potentially promising species can be reduced to several tenths. This amount is too large for systematic monitoring, since the volume of samples analyzed makes it practically impracticable to obtain and interpret results. The best choice is 2-3, the main species for each region. Such a choice should be based on the knowledge of the features of concentrating ability, of different types. The most adequate assessment of the level of metals in the environment can be obtained by species with the most pronounced compared with other ability to accumulate these elements.

Example. Collect samples of red and brown algae. From a sample of the raw biomass of each species is separated

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To maximize the narrowing of the range of 5 to 5 g to determine the initial concentration of metals in the plant. The rest of the biomass of each species is placed in vessels with sea water (25 g wet weight per 2.5 liters of water) with the addition of cadmium chloride for brown algae Gdl red - lead nitrate, as the most soluble lead salt) at a concentration of 0.5 mg / l to metal. Samples are incubated for 24 hours at 18–20 ° C, air ambiguity of the medium during 18 hours at 18–20 ° C, bubbling of the medium with air, and a photoperiod of 12 hours - light, 12 hours - darkness. Natural or artificial lighting (8-10 thousand lux). After the end of incubation, the biomass is quickly rinsed with pure water and dried to constant weight at 105 ° C. Then the samples are triturated, weighed 0.35 weighed and their IB concentrated. nitric acid, filtered, the volume of the filtrate is adjusted to 10 ml with bidistilled water, and it is determined that the concentrates contain species with such ability for not one, but several metals.

Evaluation of this ability in different types of algae can be made only in experimental conditions, since it can be determined on natural material, provided that the level of metals in the water is controlled, which is technically very difficult. In experiments, it is necessary to incubate the samples of algae on media with a high concentration of different (separately) metals with subsequent biomass analysis. #CHOJ that for several tens of species selected according to the listed criteria, this selection method takes a lot of time and is associated with the analysis of a large number of samples.

As a result of studying the accumulation of copper, zinc, manganese, cadmium, nickel and lead in 50 species of the Black Sea.

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Far Eastern and White Sea algae, it was found that their ability to accumulate some elements is interconnected, i.e. plants with a pronounced concentrating ability with respect to one element are intensively accumulated by others. Moreover, in red and brown algae, which are considered to be more successful monitors than green algae, the accumulation of various metals is interrelated.

The aim of the invention is to improve the accuracy of selection, reduce labor intensity and simplify the method by reducing the number of samples.

The method is carried out as follows.

Various types of brown and red macroalgae are harvested. Sort the resulting material into individual species, prepare samples of raw biomass of thalli and incubate them for 1 day in the presence of cadmium and lead at a concentration of 0.5 mg / l, respectively. If an excess of the absolute increase in cadmium concentration is found in brown algae over 50 µg / g dry. mass, and red lead has more than 100 µg / g dry. the masses of these species are chosen as types of monitors.

Example. Collect samples of red and brown algae. From a sample of the raw biomass of each species is separated

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cadmium radio (in red algae - lead) in control and experimental samples by the atomic absorption method. ± Calculate the content of elements in the dry material (µg / g dry. Mass) and absolute accumulation (the difference between the accumulated and the initial amount of the element). For these values, species with indicators greater than 5 are selected (L µg / g cadmium in brown algae and 100 µg / g lead in red algae.

The table presents the data on the absolute accumulation of cadmium, lead, copper, zinc, manganese, and nickel by some common types of brown and red algae after daily incubation of plants in a medium with a concentration of these elements of 0.5 mg / l. The table shows that species accumulating cadmium (for red algae - lead) in quantities exceeding

these are active concentrators of all or most of the elements tested, while species that do not meet the cadmium accumulation criteria (lead) exhibit a high concentrating ability only for individual metals.

The absolute accumulation of cadmium, lead, copper, zinc, manganese and nickel by the mass types of brown and red algae (the standard deviation e exceeds 20% of the mean values).

Thus, the use of the proposed method makes it possible to optimize the process of selecting monitor species, reducing the number of experimental options and analyzed algae samples and speeding up the entire selection process.

Claims (1)

Invention Formula A method for selecting monitor species from brown and red macroalgae, which accumulate to the maximum extent heavy metals to control the pollution of the marine environment, including the selection of algae, incubating them on the medium with the addition of salt from one of the metals, subsequent analysis of the metal content in algae, and selection of species monitors with a pronounced accumulating capacity for accumulation of heavy metals, which are distinguished by the fact that, in order to increase the accuracy of choice, reduce labor intensity and simplify the method by reducing the amount of a samples being incubated, the algae are incubated for 1 day at a metal concentration in the medium of 0.5 mg / l, while the brown algae are incubated in the presence of cadmium and the red ones in the presence of lead, and The choice of monitor species with a pronounced accumulating capacity for accumulation of heavy metals is carried out according to the content in them after incubation of one of this metal, while the monitor types are considered to be those in which the absolute increase in metal concentration after incubation exceeds cadmium 50 µg / g dry. mass, lead - 100 µg / g dry. masses.