The specification for marine monitoring --Part 3: Sample collection,storage and transportation
Some standard content:
GB 17378.3—1998
This standard is the third part of the "Ocean Monitoring Specifications", which is revised on the basis of the industry standard HY003.3-91. This standard provides principle technical regulations for sample collection, storage and transportation in ocean monitoring. The Marine Monitoring Specifications include the following parts: GB17378.1-1998 Marine Monitoring Specifications Part 1: General Principles Part 2: Data Processing and Analysis Quality Control GB17378.2-1998 Marine Monitoring Specifications GB17378.3-1998 Marine Monitoring Specifications GB 17378.4-1998 Marine Monitoring Specifications GB 17378.5-1998 Marine Monitoring Specifications Part 3: Sample Collection, Storage and Transportation Part 4: Seawater Analysis Part 5: Sediment Analysis GB 17378. 6—1998
Marine Monitoring Specification
Part 6: Biological Analysis
GB17378.7—1998
Marine Monitoring Specification
Part 7: Ecological Survey and Biological Monitoring of Offshore Pollution This standard is proposed by the State Oceanic Administration.
This standard is under the jurisdiction of the National Center for Marine Standards and Metrology. The drafting unit of this standard: National Marine Environmental Monitoring Center. The main drafters of this standard: Qu Chuanyu, Zhang Chunming, Xu Kuncan, Chen Weiyue. 367
1 Scope
National Standard of the People's Republic of China
Marine Monitoring Specification
Part 3: Sample collection, storage and transportation This standard specifies the collection procedures and the contents of sample storage and transportation of marine environmental samples. GB 17378. 3—1998
This standard applies to the sampling, storage and transportation of water quality, sediments and organisms in the marine environment, and also applies to the sampling, storage and transportation of water quality, sediments and organisms in the dumping of marine waste and dredged materials. 2 Referenced standards
The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard is published, the versions shown are valid. All standards will be revised, and the parties using this standard should explore the possibility of using the latest version of the following standards. GB/T13909--92 Marine Survey Specification Marine Geological and Geophysical Survey GB17378.4-1998 Marine Monitoring Specification Part 4: Seawater Analysis GB17378.5-1998 Marine Monitoring Specification Part 5: Sediment Analysis 3 Water Quality Samples
3.1 General Provisions
Obtaining representative samples from the marine environment and taking all precautions to avoid changes in the time interval between sampling and analysis is the first key link in marine environmental investigation and monitoring. The sampling procedure should include the following main aspects: Determine the purpose of sampling;
The temporal and spatial scale of sample collection:
Setting of sampling points;
Field sampling methods and quality assurance measures. -When designing the sampling level, the sampling purpose must be determined first. The sampling purpose is the main basis for determining the sampling location, sampling frequency, sampling time, sample processing and analysis technology requirements. Sampling is usually divided into three types: environmental quality control, environmental quality characterization, and pollution source identification: Environmental quality control refers to repeated verification of the concentration of one or several environmental elements in a certain sea area. The verification results determine whether to take corresponding measures to the environmental conditions in a timely manner. Environmental quality characterization is to control environmental quality in the long term, analyze and evaluate the current spatial and temporal distribution of pollutants in the marine environment, and predict the development trend of marine environmental conditions. Pollution source identification is to determine the characteristics of pollutant emissions and trace the pollution pathways of pollutants.
Due to the different sampling purposes in the marine environment, different sample types and analysis methods, it is impossible to prescribe very detailed steps for the collection process of all water quality samples. In other words, no sampling procedure is suitable for the collection of all types of water quality samples. Approved by the State Administration of Quality and Technical Supervision on June 22, 1998 368
Implemented on January 1, 1999
3.1.1 Safety measures
GB 17378.3—1998
For sampling of water quality, sediment and organisms, corresponding safety rules and regulations must be formulated and implemented conscientiously. 3.1.1.1 Careful consideration must be given to ensuring the safety of operators and instruments and equipment under various weather conditions. When sampling on large areas of water, operators must wear safety belts and prepare life buoys, and various instruments and equipment should take safety fixing measures. Before sampling in ice-covered waters, the location and range of thin ice must be carefully checked first. If a complete set of breathing apparatus and other diving equipment is used for underwater sampling, its reliability must be checked and maintained regularly. 3.1.1.2 Sampling vessels should prevent merchant ships, fishing boats and other vessels from approaching when sampling in all waters, and should use various signals at any time to indicate the nature of the work being done.
3.1.1.3 Try to avoid sampling in unsafe places such as dangerous shores. If it is unavoidable, do not do it alone, but do it in a group, and take corresponding measures. If conditions permit, try to sample in safe places such as bridges and docks. Sampling equipment installed on the shore or in shallow waters should take protective measures.
3.1.1.4 When sampling, take some special protective measures to avoid certain accidental situations. Such as: corrosive, toxic, flammable and explosive, virus and harmful animals, etc. harm to the human body.
3.1.1.5 When using electrically operated sampling equipment, strengthen safety measures during operation and maintenance. 3.1.2 Samples
3.1.2.1 Sample Types
3.1.2.1.1 Instantaneous Samples
Instantaneous samples are discontinuous samples. Whether at the surface or at a specified depth and bottom layer, they should generally be collected manually, and in some cases they can also be collected by automatic methods.
Instantaneous samples should be collected when investigating possible pollution in a certain range of sea areas or investigating and monitoring its pollution level, especially when sampling over a larger area. For certain items to be tested, such as water samples for dissolved oxygen, dissolved hydrogen sulfide and other dissolved gases, it is required to collect instantaneous samples. 3.1.2.1.2 Continuous Samples
Continuous samples usually include collecting timed samples at fixed time intervals (depending on time) and collecting timed samples at fixed flow intervals (depending on volume). The above are often used in special cases such as direct sewage outlets into the sea to reveal changes that cannot be observed using instantaneous samples.
3.1.2.1.3 Mixed samples
Mixed samples refer to the mixture of several individual samples based on flow, time and volume at the same sampling point. Mixed samples are used to provide average data of components. If the components to be tested in the water sample change significantly during the collection and storage process, the mixed water sample cannot be used, and it must be collected and stored separately.
3.1.2.1.4 Comprehensive water sample
Comprehensive water sample refers to the water sample obtained by mixing water samples collected from different sampling points at the same time (the time is not exactly the same, but as close as possible). Sometimes a suitable comprehensive water sample may provide more useful data. 3.1.2.2 Requirements for samples
Characterization of a certain environment It is impossible to examine its entirety. Only a small part can be taken out to represent the whole to be characterized. Once the sample is collected, it must be kept in the same state as when it was sampled. Qualified samples must have high representativeness and authenticity. In order to make the samples representative of the whole to be characterized, the sampling section, sampling point, sampling time, sampling frequency and number of samples of the monitored sea water body must be carefully considered and designed, so that the data obtained by the sample analysis can objectively represent the real situation of the water body. Samples are very susceptible to contamination during collection, storage and analysis and testing, such as contamination from the hull, water sampling equipment, experimental equipment, glassware, chemicals, air and the operator himself. The components to be tested in the sample may also be lost due to adsorption, sedimentation or volatilization.
In a sense, in the investigation and monitoring of the marine environment, the quality assurance of samples is the whole process of overcoming sample contamination and loss. 3.2 Determination of sampling location and selection of time and space frequency 369
GB 17378.3—1998
The determination of sampling locations and the selection of temporal and spatial frequencies should first be based on an objective analysis of a large amount of historical data, and then the characteristic zoning of the surveyed and monitored sea areas should be carried out. The key to characteristic zoning lies in the central trend of historical data at each station and the determination of characteristic zoning standards. According to the temporal and spatial characteristics of the uneven distribution of pollutants in a large area of sea and the relative uniformity of local sea areas, the monitoring sea areas are divided into: polluted areas, transition areas and control areas using classification methods such as homogeneous analysis and fuzzy set clustering analysis. 3.2.1 Layout of sampling stations
The main sampling stations should be reasonably arranged in sea areas where the environmental quality has changed significantly or has important functional uses, such as near-shore estuaries or near major pollution sources. During the initial pollution survey of the sea area, grid-type points can be arranged. There are many factors that affect the layout of the stations, but they should mainly be based on the following principles: being able to provide representative information;
environmental and geographical conditions around the station;
-dynamic field conditions (tidal field and wind field); socio-economic characteristics and the impact of regional pollution sources; the degree of navigation safety around the station;
economic benefit analysis;
try to consider the uniformity of the geographical distribution of the measuring points, and try to avoid the system boundaries of the characteristic division. 3.2.2 Sampling time and sampling frequency
Sampling during the period when water quality may change can not only reflect the change of water quality, but also spend less cost. Choosing the sampling time and frequency based on subjective assumptions often leads to blindness or waste due to too frequent sampling. Principles for determining the sampling time and frequency:
how to meet the required data for reflecting environmental information with the least workload; technical possibility and feasibility;
can truly reflect the characteristics of changes in environmental factors; try to consider the continuity of sampling time.
Spectral analysis is accurate and concise. It can be used as a method to determine the sampling time and frequency. According to the change curve of the amount of pollutants entering the sea drawn from a large amount of data, the sampling time and sampling frequency can be determined at the highest expectation or higher expectation of the change. In addition, using many years of survey and monitoring data, appropriate parameters are used as statistical indicators to conduct time clustering analysis. The sampling time and sampling frequency can also be determined based on the time clustering results. Other statistical methods can also be used to conduct statistical tests to determine the sampling time and frequency.
The sampling frequency used for environmental quality control is generally higher than the sampling frequency required for environmental quality characterization; the sampling procedure for pollution source identification is different from the environmental quality control and environmental quality characterization procedures. There are many factors that affect the determination of sampling time and sampling frequency, and its sampling frequency is much higher than the frequency of pollutant occurrence.
Sampling level
Water depth range
Less than 10
50~100
Above 100
Surface layer, bottom layer
Surface layer, 10, bottom layer
Standard layer
Surface layer, 10,50. Bottom layer
Surface layer, 10.50, add layers as appropriate for the water layer below, the bottom layer and surface layer refer to 0.1~1m below the sea surface
Minimum distance between the bottom layer and the adjacent standard layer
2 Bottom layer, for estuaries and harbors, it is best to take a water layer 2m away from the seabed. In deep sea or strong winds and waves, the distance from the bottom layer can be increased as appropriate. 3.3 Sampling device
3.3.1 Technical requirements for water quality samplers
3.3.1.1 Good filling and sealing properties; GB 17378. 3-1998
The structure of the sampler should be tight, the closing system should be reliable and not easy to be blocked, and the exchange of seawater and water in the sampling bottle should be sufficient and rapid. The number of parts should be reduced to a minimum.
3.3.1.2 The material should be corrosion-resistant, non-staining and non-adsorbing; the trace metal water sampler should be a non-metallic structure, usually with polytetrafluoroethylene, polyethylene and polycarbonate as the main materials. If metal materials are used, non-metallic coatings should be applied to the surface of the metal structure. 3.3.1.3 The structure should be simple, light, easy to rinse, easy to operate and maintain, no sample residue before sampling, and convenient sample transfer. 3.3.1.4 It can resist the influence of harsh climate and adapt to operation under a wide range of environmental conditions. It can work in an environment with a temperature of 0-40℃ and a relative humidity of no more than 90%.
3.3.1.5 It is cheap and easy to promote and use. 3.3.2 Sampler Types
Commonly used water quality samplers can be divided into three types: instantaneous sample samplers, depth integrated method sample samplers and selected depth samplers.
3.3.2.1 Instantaneous Sample Samplers
3.3.2.1.1 Nearshore Surface Water Sampler
A bottle clamp wrapped in plastic is connected to a retractable long pole, and the sampling bottle is fixed on the plastic bottle clamp. The sampling bottle is the sample bottle. 3.3.2.1.2 Floating Water Sampler
The sampling bottle is installed in an openable stainless steel fixed frame. The steel frame is connected to the float with a fixed length of nylon rope. It is usually used to collect surface petroleum hydrocarbons and other water samples.
For instantaneous sample collection at selected depth, the type of sampler described in Section 3.3.2.3 is used. If the average water quality of a vertical section of a water body is to be investigated, the relevant samplers in the integrated depth sampling method described in 3.8.2.2 shall be used. 3.3.2.2 Integrated depth sampling device
Integrated depth sampling requires a set of mechanical devices to clamp the sampling bottle and sink it into the water. The sampling bottle with weights sinks into the water, and the water samples of each layer of the entire vertical section enter the sampling bottle through the injection valve. In order to collect water samples in proportion at various depths, the speed of sinking or lifting of the sampling bottle should also change accordingly with the depth. At the same time, an adjustable injection hole should be provided to keep the injection flow constant under the condition of water pressure changes. In the absence of the above sampling equipment, an open-closed water sampler can be used to collect samples of each depth layer separately and then mix them. The open-closed water sampler is a simple and easy-to-use sampler with openings at both ends and openable lids at the top and bottom. The water sampler is open and sunk into the water. When it reaches the sampling depth, the lids at both ends are closed according to the instructions, and the sample of the required depth can be obtained at this time. 3.3.2.3 Selected depth fixed point water sampler (closed-open-closed water sampler) The sampling bottle fixed on the sampling device is submerged in the water body in a closed state. When the sampler reaches the selected depth, it opens according to the command. After the sampling bottle is filled with water sample, it closes according to the command. The closed-open-closed water sampler made of non-metallic materials is very suitable for the collection of trace metal samples. 3.3.2.4 Pump suction system water sampler
The pump suction system water sampler can obtain a large volume of water samples, and can study the "fine structure" of the water body in vertical and horizontal directions for continuous sampling. It can also be used in conjunction with CTD and STD parameter monitors, making it unique. The suction height of the sampling pump should be minimized, and the entire pipeline system should be tight.
3.4 Sampling cables and other equipment
To prevent sample contamination during the sampling process, the hydrographic wire rope should be coated with non-metallic materials or replaced with plastic ropes. The hammer should be sprayed with materials such as polytetrafluoroethylene and polyethylene.
Anti-contamination measures should also be taken for the hydrographic winch. 3.5 Washing and storage of sampling bottles
The washing of sampling bottles shall be carried out in accordance with the requirements of 3.8.1. After each sampling, the sampling bottles shall be placed in a plastic bag for storage and shall not be in direct contact with the hull or other sources of contamination.
3.6 On-site sampling operation
GB17378.3-1998
The performance of the device and the safety conditions around the sampling point shall be carefully checked before each sampling. 3.6.1 Onshore sampling
If the water is flowing, the sampling personnel standing on the shore must face the direction of the water flow when operating. If the bottom sediment is disturbed, sampling cannot continue.
3.6.2 Sampling on ice
If the ice is covered with snow, a wooden or plastic shovel can be used to clear out a 1.5m×1.5m snow patch, and then an ice drill or electric saw can be used to make a hole in the center. Since the ice drill and saw teeth are made of metal, this increases the possibility of water contamination. After the ice hole is made, use an ice scoop (if taking trace metal samples, the ice scoop needs to be wrapped in plastic) to remove the crushed ice. At this time, special care must be taken to prevent the sampler's clothes and shoes from contaminating the ice around the hole. Sampling can only be done after a few minutes.
3.6.3 Sampling on board
Since the hull itself is an important source of pollution, appropriate measures must always be taken during sampling on board to prevent the possible impact of various pollution sources on board.
3.6.3.1 Sampling on small boats: Try to avoid using small boats made of iron or other metals when sampling trace metal water samples. ：3.6.3.2 Sampling from large ships: Use sampling against the wind to control all kinds of pollution from the hull to a level as low as possible. When the hull arrives at the sampling station, the sea surface around the sampling ship should be immediately divided into three parts according to the wind direction and flow direction: hull pollution area, wind-induced pollution area and sampling area, and then sampling should be carried out in the sampling area. Or after the engine is turned off, when the hull is still moving slowly, throw the floating water sampler forward as far as possible from the bow, or use a small boat to leave the large ship and take samples after a certain distance. On the ship, the sampling personnel should insist on operating against the wind, the sampler cannot directly touch any part of the hull, and the sampler drain port cannot be touched with bare hands. First, drain a part of the water sample in the sampler before taking samples. 3.7 Storage and transportation of samples
3.7.1 Material selection of sample containers
The material of the container for storing water samples should be selected according to the following principles: the degree of contamination of water samples by the container material should be minimal; it should be easy to clean and treat the container wall;
the material of the container should be chemically and biologically active, so that the interaction between the sample and the container is kept at the lowest level. When selecting a container for storing samples, the strain capacity to temperature changes, crack resistance, sealing, ability to open repeatedly, volume, shape, quality, supply status, price and possibility of reuse should also be considered. Most samples containing inorganic components are made of containers made of polyethylene, polytetrafluoroethylene and polycarbonate polymers. Commonly used high-density polyethylene is suitable for the storage of samples for analysis and determination of silicate, sodium salt, total alkalinity, chloride, conductivity and pH in water. For photosensitive substances, light-absorbing glass materials are often used.
Commonly used glass containers are suitable for the storage of organic compounds and biological species samples. Plastic containers are suitable for storing radionuclides, most trace elements and water samples for routine measurement items. Containers with neoprene and oil-lubricated valves are not suitable for storing organic and microbial samples.
3.7.2 Washing of sample containers
In order to minimize the contamination of samples, new containers must be thoroughly cleaned. The type of detergent used depends on the composition of the substance to be measured. For general use, dust and packaging materials can be cleaned with tap water and detergent, then soaked with chromic acid and sulfuric acid detergent, and then rinsed with distilled water. Used containers often have oil, heavy metals and sediments adsorbed and attached to the walls and bottoms. According to different experimental requirements, they should generally be avoided. If they must be used again, they must be thoroughly cleaned with a brush before use. For stoppered glass bottles, dissolution, adsorption and adhesion often occur at the ground mouth. Polyethylene bottles are particularly prone to adsorbing oil, heavy metals, sediments and organic matter, which are difficult to remove, so great attention should be paid. 372
GB 17378. 3—1998
When using polyethylene containers, first clean them with 1 mol/L hydrochloric acid solution, and then soak them in 1+3 nitric acid solution for a long time. Glass bottles used for the determination of trace organic matter can only be cleaned with inorganic reagents. Water sample bottles used for storage of counting and biochemical analysis should also be soaked in nitric acid solution, and then rinsed with distilled water to remove any heavy metal and chromate residues. If the organic components to be determined need to be extracted before determination, in this case, the glass bottles can also be treated with extractants. 3.7.3 Fixation and storage of water quality samples
Fixation of water quality samples usually adopts two methods: freezing and acidification followed by low-temperature refrigeration. Acid (hydrochloric acid or nitric acid) is added to the filtered water sample to acidify it so that the pH value is maintained at less than 2. Then it is refrigerated at low temperature. Unfiltered samples cannot be acidified, as acidification can desorb trace metals on particulate matter. Unfiltered water samples must be stored frozen. For details on the on-site treatment and storage of water samples, please refer to the provisions of GB17378.4. 3.7.4 Sample transportation
Empty sample containers should be sent to the sampling site or containers filled with samples should be transported back to the laboratory for analysis with great care. The packaging box can be made of a variety of materials to prevent breakage, maintain sample integrity, and minimize sample loss. The lid of the packaging box should generally be lined with isolation material to apply slight pressure to the bottle stopper and increase the fixation of the sample bottle in the sample box. 3.7.5 Quality control of sample containers
Each laboratory should implement an effective container quality control procedure. Randomly select cleaned sample bottles and inject high-purity water for analysis to ensure that there are no impurities left in the sample bottles. During the sampling and storage process, the same reagent as the analysis sample should also be added to the sample bottle injected with high-purity water for analysis to assess the degree of variation in sample quality. 3.7.6 Marking and recording
After the sample is injected into the sampling bottle, the source of the sample and the sampling conditions should be recorded immediately and marked on the sample bottle. Field records are very useful in marine environmental surveys and monitoring, but they can easily be misplaced or lost. They must never be relied upon as a substitute for detailed information. Detailed sampling records must accompany the sample from the time of sampling until the tabulation process at the end of analytical testing. 4 Sediment samples
4.1 Sample collection
4.1.1 Collection of surface samples
4.1.1.1 Types of samplers and their selection
Grab-type or other types of sediment samplers designed with their own weight or leverage have different design features, including spring brakes, gravity or toothed plate locking methods. These vary with the shape of the deep mud layer, as well as the size and area of the samples taken. The selection of samplers mainly considers the following aspects.一 Depth of penetration through mud layer;
---Angle of tooth plate locking;
一 Locking efficiency (ability to avoid obstacles); 一 The degree of causing wave "oscillation" and sample loss or washing away sample components or organisms at the mud-water interface; Stability of samples in rapids. When selecting a sediment sampler, the habitat, water flow conditions, sampling area and sampling vessel equipment should be considered comprehensively.
Commonly used grab bucket mud samplers are very similar to ground excavation equipment. They are lowered to the selected sampling point by a hydrographic winch. Usually, collecting a large amount of mixed samples can more accurately represent the conditions of the selected sampling location. 4.1.1.2 Surface sample collection operation
4.1.1.2.1 Connect the winch wire rope to the mud sampler and check whether it is firm. At the same time, measure the water depth of the sampling point; 4.1.1.2.2 Slowly start the winch to put the mud sampler into the water. After stabilization, lower it to a certain distance of 3 to 5 meters from the seabed at normal speed, and then lower it to the seabed at full speed. At this time, the wire rope should be appropriately lengthened, especially when the waves are large and the current is fast; 4.1.1.2.3 After slowly lifting the mud sampler from the bottom, quickly lift it to the water surface, and then slowly. When the mud sampler is higher than the boat, stop it and gently lower it to the sample receiving board;
4.1.1.2.4 Open the upper ear cover of the mud sampler, gently tilt the mud sampler, and let the upper water flow out slowly. If the mud sampler is washed by seawater during the lifting process, causing too much sample loss, or because the sediment is too soft and the mud sampler descends too sharply, the sediment emerges from the ear cover, it should be re-collected; 4.1.1.2.5 After the sample is processed, discard the residual sediment in the mud sampler, rinse it clean, and set it aside. 4.1.2 Collection of columnar samples
The columnar sampler can collect vertical cross-section sediment samples. If the collected sample itself does not have mechanical strength, then be careful to maintain the longitudinal integrity of the mud sample when removing the sample from the mud sampler. Collection operation of columnar samples
4.1.2.1 First, check whether the various components of the columnar sampler are safe and firm; 4.1.2.2 Take surface samples first to understand the nature of the sediment. If it is gravel sediment, do not take gravity samples; 4.1.2.3 After determining to take gravity samples, start the winch slowly, slowly put the mud sampler into the water, wait for the sampling tube to stabilize in the water, lower it at normal speed to 3 to 5 meters from the sea, then lower it to the seabed at full speed, and stop immediately; 4.1.2.4 Slowly lift the sampler, quickly lift it to the surface after leaving the bottom, and then slow down again. After parking, hook the tube with an iron hook, turn it inside, and lie it flat on the deck;
4.1.2.5 Carefully pour out the water on the top of the sampling tube and measure the depth of the sampling tube. Then use a cleaning rod to slowly squeeze out the sample column and place it on the sample receiving board in order for processing and description. If the sample column is not long enough or the sample tube is inserted obliquely into the seabed, it should be re-sampled;4.1.2.6 After the column sample is squeezed out, clean the inside and outside of the sampling tube, place it safely and set aside. 4.2 On-site description of the sample
4.2.1 Color, smell and thickness
4.2.1.1 Color: Color can often reflect the environmental conditions of the sediment, and it should be implemented in accordance with GB/T13909. 4.2.1.2 Smell: After the sample is collected, use the sense of smell to immediately identify whether there is oil smell, hydrogen sulfide smell and the severity of the smell. 4.2.1.3 Thickness: There is often a light-colored thin layer on the surface of the sediment, which can indicate its sedimentation environment. When sampling, you can gently insert a glass test tube into the sample, take it out, and measure the thickness of the light-colored layer. When sampling in a column, you can describe the depth of the sampling tube, the actual length of the sample column, and the thickness of the natural layer. 4.2.2 Sediment type
According to GB/T13909.
4.2.3 Biological phenomena
Includes:
- Shell content and degree of fragmentation;
- Types and quantities of organisms;
Remains of biological activities;
Other characteristics
According to GB/T13909.
The above characteristics of sediment samples should be clearly, accurately and briefly recorded in the sampling record. The collection, processing and preparation of analytical samples shall be carried out in accordance with the requirements of "Sediment Analysis" in GB17378.5-1998. 4.3 Sample Storage and Transportation
4.3.1 Sample Storage
All wide-mouth bottles for samples shall be filled with nitrogen and placed in a cool place, preferably refrigerated at low temperature. In general, samples can also be stored in a dark place.
4.3.2 'Sample Transportation
In principle, it shall be carried out in accordance with Article 3.7.4.
· 4.3.3 Sample registration
The sample bottles should be numbered in advance, and labels should be affixed after loading. The station number and level should be written on the sample bottles with a special pencil to prevent the labels from falling off and messing up the samples.
Plastic bags should be taped, and the station number and level should be marked with a marker. The written labels should be placed in the bags and sealed. Carefully record the sampling site.
5 Biological samples
5.1 Purpose of sample collection and sample source
5.1.1 Purpose
GB 17378. 3—1998
Understand the accumulation, distribution and transfer metabolism of pollutants in organisms, evaluate the content of pollutants in the sea area and its changes over time, calculate the mass balance of pollutants in the marine environment, and evaluate the quality of the marine environment. Protect marine biological resources and protect human health. 5.1.2 Sources of biological samples
Includes:
Benthic trawling at biological stations;
-Sampling of near-shore fixed-point aquaculture;
-Fishing by fishing boats;|| tt||Fishing and fishing with fixed nets in coastal waters;www.bzxz.net
Purchase directly from the market. Including commercial fish, shellfish and some algae. 5.2 General principles for selecting samples
5.2.1 Can accumulate pollutants and have a certain tolerance to pollutants, and the pollutant content in its body is significantly higher than that in the water where it lives; 5.2.2 Marine organisms that are directly eaten by humans or indirectly eaten by humans as part of the food chain; 5.2.3 Existing in large quantities, widely distributed, and easy to collect; 5.2.4 Having a long life cycle 5.2.5 The species should have a long life span and can live for at least one year; 5.2.6 The species should have a long life span and remain alive after the sample is collected; 5.2.6 The species should live in a certain sea area and have low mobility; 5.2.7 The sample should be of appropriate size so that there is enough meat for analysis; 5.2.8 The dominant species and common species in the biological population. 5.3 Sample collection
5.3.1 Sampling location
Considering the representativeness of the sample and the need to evaluate the environmental quality, the sampling location should be mainly in the nearshore waters, in principle, at the water quality station and A biological station should be set up at each bottom sediment station.
The sampling location should be chosen to avoid local influences and should not be set close to pollution sources. 5.3.2 Sampling season
Sampling should be carried out when the biological growth is relatively stable. Generally speaking, sampling can be carried out in late winter and early spring. If you want to understand the changes in pollutants contained in organisms in different seasons, sampling should be carried out in each season. 5.3.3 Age and size of samples
Choose the type of biological population that is dominant in age, size and weight. 5.4 Sampling tools
When sampling, attention should be paid to the influence of sampling tools on the items to be tested. General iron tools and galvanized or chrome-plated tools cannot be used to measure metal items. Stainless steel knives, scissors, etc. can be used for the dissection of fish and shellfish. 5.5 Description of the sampling site
When sampling, truthfully record the sampling date, the location and sampling depth of the sampling sea area, the characteristics of the sampling sea area, the sampling method used, and the types of organisms collected. If the sample has been identified, the age, size, weight, gender, etc. of the sample, the items to be analyzed, the storage method, the treatment method, etc. should be recorded.
5.6 Transportation of samples
The packaged samples should be sent back to the laboratory as quickly as possible. During transportation, effective measures should be taken to prevent them from rotting and deterioration. Protect the samples and the marks on the sample packaging to avoid confusion or damage. 375
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