Method for identifying and analyzing breeding biological characteristics of schizothorax in plateau area

Abstract

The invention provides an identification and analysis method for breeding biological characteristics of schizothorax in a plateau area. The invention discloses a plateau region schizothorax fish breeding biological characteristic identification and analysis method. The method comprises the following steps: S1, sample collection and basic data acquisition; s2, fish gonad development staging and reproduction cycle determination; s3, accurate age identification and growth relation establishment; s4, primary sexual maturity identification and analysis; s5, determining breeding seasons and periods; s6, determining spawning types; s7, high-precision fish fecundity determination and analysis; s8, carrying out correlation analysis on the reproductive capacity model and the environmental factors; and S9, evaluating a population breeding strategy and vulnerability. The plateau region schizothorax breeding biological characteristic identification and analysis method provided by the invention has the advantages that complete process operation from sample treatment to ecological evaluation can be realized, and the problems of scattered methods, low data precision and disjunction with environmental factors in the prior art can be solved.

Description

Technical Field

[0001] This invention relates to the field of aquatic fishery resource survey and protection technology, and in particular to a method for identifying and analyzing the reproductive biological characteristics of schizothorax fish in plateau regions. Background Technology

[0002] The unique environment and climate of plateau regions, with water temperature variation patterns significantly different from those of plains, lead to unique reproductive biology adaptations in cold-water fish (such as schizothorax). Their breeding seasons and spawning patterns (spring or autumn spawning, batch or single spawning) may exhibit distinctive characteristics. Therefore, developing a systematic identification and precise quantitative analysis methodology for the reproductive biological characteristics of cold-water fish in plateau regions requires moving beyond the traditional research framework primarily focused on warm-water fish from plains.

[0003] Currently, research on the reproductive biology of schizothorax fishes in high-altitude areas suffers from the following shortcomings:

[0004] The methods are fragmented and lack systematicity: existing studies are mostly isolated links, such as studying only fertility or only determining the breeding season, failing to form a complete technical chain from sample collection to population assessment, resulting in data fragmentation and the formation of "data silos".

[0005] Key parameters are difficult to obtain accurately and are highly subjective: for example, age determination relies on human experience, and egg counting uses traditional manual methods, which are inefficient and prone to errors.

[0006] Disconnected from environmental factors: Traditional methods often overlook the profound impact of special environmental stresses on plateaus (such as low temperature, strong radiation, and hydrological changes) on fish reproduction, and fail to quantitatively correlate environmental data with biological characteristics, making it difficult to directly apply research results to resource conservation practices.

[0007] Therefore, it is necessary to provide a new method for identifying and analyzing the reproductive biological characteristics of schizothorax fish in plateau regions to solve the above-mentioned technical problems. Summary of the Invention

[0008] The technical problem solved by this invention is to provide a method for identifying and analyzing the reproductive biological characteristics of schizothorax fish in plateau areas that can realize a complete and streamlined operation from sample processing to ecological assessment, and can solve the problems of fragmented methods, low data accuracy, and disconnection from environmental factors in existing technologies.

[0009] To solve the above-mentioned technical problems, the present invention provides a method for identifying and analyzing the reproductive biological characteristics of schizothorax fish in plateau regions, comprising the following steps:

[0010] S1: Sample collection and basic data acquisition: Systematic sampling is carried out in the target water area on a quarterly or monthly basis, covering the complete breeding cycle and different age groups. Biological measurements are performed on the collected samples, including body length, weight, and sex identification, to determine sexually mature individuals. Scales or microotoliths are collected for age identification, and gonads are removed for fixation.

[0011] S2: Determination of the developmental stages and reproductive cycle of fish gonads: By preparing paraffin sections of gonads and staining them, the morphology of reproductive cells is observed under a microscope. Based on the phase of oocytes, the accumulation of yolk, and the state of follicular cells, the developmental stages of the ovary and testes are accurately divided.

[0012] S3: Precise age determination and growth relationship establishment: Use a microscope or microscopic imaging system to read the growth rings, have at least two researchers interpret the age data, and conduct relevant growth analysis with body length and weight to establish the Von Bertalanffy growth equation;

[0013] S4: Primary Sexual Maturity Identification Analysis: Using a logistic regression model, based on the proportion of sexually mature individuals in body length and age segments, the average body length and average age at primary sexual maturity were determined. The formula is as follows:

[0014]

[0015] and

[0016]

[0017] Where P represents the proportion of sexually mature individuals. Let A be the median value of the body length range, A be the median value of the age range, and k be a constant. The average body length at first sexual maturity. : The average age of first sexual maturity;

[0018] S5: Determination of Breeding Season and Period: Based on the annual variation curve of the Gonadal Maturity Index (GSI) and the composition of gonadal stages, the peak breeding period, the beginning period, and the end period are determined. The formula for calculating the Gonadal Maturity Index is as follows:

[0019] GSI = (GW / BW) × 100%

[0020] Wherein, GW is gonadal weight, BW is body weight, and GSI is maturity index;

[0021] S6: Ovulation type determination: By measuring the diameter of oocytes in the ovaries from stage III to IV and drawing an oocyte diameter frequency distribution map, the ovulation type can be determined as either a single ovulation or batch ovulation.

[0022] S7: High-precision fish fertility measurement and analysis: three segments of tissue (anterior, middle and posterior) were taken from the fixed ovary, weighed, and then the number of eggs was automatically identified and counted using image analysis software. The absolute fertility of the individual, the relative fertility of body length, the relative fertility of body weight, the gonadal maturity coefficient, the degree of fatness and the contribution rate were calculated.

[0023] S8: Correlation analysis between reproductive capacity model and environmental factors: Collect environmental data of spawning grounds during the breeding season, including water temperature, dissolved oxygen, pH value, flow velocity and substrate type. Perform power function regression analysis on absolute reproductive capacity with body length, weight and age. Select the model with the highest coefficient of determination as the prediction model. Analyze the impact of environmental fluctuations on reproductive capacity through a generalized linear model.

[0024] S9: Population reproductive strategies and vulnerability assessment: Based on the age of first sexual maturity, reproductive capacity, egg type and egg diameter, determine whether the species adopts r-selection or K-selection strategies, construct a population growth model, and assess the population vulnerability index.

[0025] Preferably, in S1, the biological measurements include body length measurement accurate to millimeters, weight measurement accurate to grams, and gonad fixation using formalin or Bouin's fixative.

[0026] Preferably, in step S2, the criteria for classifying the stages of gonadal development include:

[0027] Stage I: The gonads are linear in structure, translucent or pale flesh-colored;

[0028] Stage II: The ovaries appear as thin threads or flat bands, with no visible eggs, and the testes are thin and thread-shaped.

[0029] Stage III: The ovaries are enlarged, the eggs are clearly visible but adhered together, and the testes are cylindrical;

[0030] Stage IV: The ovaries occupy most of the abdominal cavity, the eggs are plump and easily separated, and the testes are milky white;

[0031] V stage: The eggs mature and flow out; gentle pressure on the abdomen can release either eggs or sperm.

[0032] Stage VI: The ovary is atrophied and congested, containing empty follicles and degenerated oocytes.

[0033] Preferably, in step S3, if the age determination results are inconsistent, the determination shall be made by a third party through arbitration.

[0034] Preferably, in step S4, the body length segment is divided into 10mm segments, and the age segment is divided into 1-year segments.

[0035] Preferably, in S7,

[0036] The formula for calculating the absolute fertility of an individual is: ;

[0037] The formula for calculating the relative reproductive capacity of body length is: ;

[0038] The formula for calculating body mass relative to fertility is: ;

[0039] The formula for calculating the gonadal maturity coefficient is: ;

[0040] The formula for calculating fullness is: ;

[0041] The formula for calculating the contribution rate is: ;

[0042] In the formula, The number of gonadal ovules collected (in ovules); The mass (g) of the gonads taken; Fish ovary mass (g); F represents individual fertility; , where L is the average absolute fertility of individuals in the age group (seeds / tail); L is the individual body length in mm; Net body weight (g); N is the number of samples (tails) in this age group; The total fertility (number of grains) of the fish samples tested.

[0043] Preferably, in step S7, the image analysis software uses automatic recognition technology to count the eggs, with no less than 100 eggs measured per fish.

[0044] Preferably, in step S8, the environmental factor data is obtained through sensors or on-site measurements, and the generalized linear model is used to quantify the effects of water temperature, dissolved oxygen, and flow rate on reproductive capacity.

[0045] Preferably, in S9, the population vulnerability assessment includes calculating a vulnerability index based on K-selection characteristics, which is used to formulate protection levels and measures.

[0046] Compared with related technologies, the method for identifying and analyzing the reproductive biological characteristics of schizothorax fish in plateau regions provided by this invention has the following beneficial effects:

[0047] This invention provides a method for identifying and analyzing the reproductive biological characteristics of schizothorax fish in plateau regions. It organically integrates all aspects of reproductive biology research into a coherent whole, ensuring the standardization of the research process and the comparability and reproducibility of the results. Through multi-person arbitration for age determination and automatic egg counting via image recognition, it effectively solves the problems of strong subjectivity, low efficiency, and large errors in traditional methods, significantly improving the accuracy of key parameters (such as age and fertility). It mandates the inclusion of quantitative environmental monitoring data in the analysis framework and uses mathematical models to quantitatively reveal how environmental stress affects reproductive success, enabling research results to directly serve the assessment of the impact of climate change on plateau aquatic ecosystems. By introducing life history theory analysis and quantitative assessment of population vulnerability, it transforms biological data into quantitative indicators that can predict population development trends. The resulting results, such as fishing ban periods, minimum catch sizes, and threat levels, can be directly used by management departments, thus achieving efficient transformation of scientific research results into conservation practices. Attached Figure Description

[0048] Figure 1 The flowchart shows the method for identifying and analyzing the reproductive biological characteristics of schizothorax fish in plateau regions provided by this invention. Detailed Implementation

[0049] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0050] Please refer to the following: Figure 1 ,in, Figure 1 A flowchart illustrating the method for identifying and analyzing the reproductive biological characteristics of schizothorax fish in plateau regions, provided by this invention. The method includes the following steps:

[0051] S1: Sample Collection and Basic Data Acquisition

[0052] Systematic sampling will be conducted quarterly or monthly in the target waters, covering the entire breeding cycle and different age groups to obtain representative breeding populations. Basic biological measurements will be performed on the collected samples, including body length, weight, and sex identification. For sexually mature individuals, scales and microotoliths will be collected for age determination, establishing the age structure of the breeding population. The gonads will be completely removed, rapidly weighed (accurate to 0.01g), and fixed with formalin or Bouin's fixative for subsequent analysis.

[0053] S2: Determination of Gonadal Development Stages and Reproductive Cycles in Fish

[0054] S201: By combining internal and external characteristics of fish during the breeding season, gonads of collected and fixed fish samples are used to prepare paraffin sections of the gonads and then stained.

[0055] S202: By observing the morphology of germ cells under a microscope, the developmental stages of the ovary and testis (stages I to VI) can be accurately divided based on the oocyte phase, yolk accumulation, and follicular cell status.

[0056] Stage I: The gonads appear as extremely fine linear structures, closely attached to the body cavity membrane, and are usually translucent or pale flesh-colored.

[0057] Stage II (Oogonia Proliferation Stage): The ovary appears as a thin thread or flat band, and the eggs are not visible to the naked eye. The testes are thin and linear, with underdeveloped blood vessels. This stage is characterized by the massive proliferation of oogonia.

[0058] Stage III (Oocyte Mini-Growth Phase): The ovary significantly enlarges, turning pale yellow or bluish-gray. Eggs are clearly visible but adhered together and difficult to separate. The testes become rod-shaped with increased surface blood vessels. During this stage, oocytes begin to accumulate pre-vital material.

[0059] Stage IV (Oocyte Maximal Growth Stage): The ovary reaches its maximum size, occupying most of the abdominal cavity. It is richly vascularized and highly congested, appearing deep yellow or pale orange-yellow. The eggs are plump, uniform in size, and easily separated, maintaining their spherical shape when placed in water or a fixative solution (such as Born's solution). The testes are milky white, and a small amount of semen may flow out when the abdomen is gently pressed. This stage is crucial for determining whether the parent fish are ready for artificial spawning.

[0060] Stage V (Ovulation): The oocyte completes maturation division, detaches from the follicle, enters the ovarian cavity, and becomes a flowing, mature egg. The parent fish's abdomen swells and softens; the eggs are transparent, elastic, and disperse upon contact with water. Gently pressing the female's abdomen allows the eggs to flow out smoothly, while the male can expel a thick, milky-white sperm. During this stage, the parent fish can spawn naturally or undergo artificial insemination.

[0061] Stage VI (Postpartum): The ovaries atrophy, become relaxed and congested, and appear dark red, containing numerous empty follicles and unexpelled degenerated ovum (albinoblastic eggs). The testes become smaller and dark red. During this stage, the gonads enter a phase of degeneration and absorption.

[0062] S3: Establishing the Relationship Between Precise Age Determination and Growth:

[0063] S301: The annual rings of fish samples are read using a microscope and microotoliths after grinding, respectively, under a dissecting microscope and a microscopic imaging system. The readings are interpreted by at least two experienced researchers, and in case of discrepancies, a third party shall arbitrate.

[0064] S302: Perform correlation growth analysis between age data and the corresponding individual's body length and weight to establish the Von Bertalanffy growth equation.

[0065] S303: Statistically determine the sexual maturity rate of individuals in each age group, and use a logistic regression model to determine the age of first sexual maturity and the length of first sexual maturity.

[0066] S4: Primary Sexual Maturity Identification Analysis:

[0067] Primary sexual maturity refers to the average age and size at which 50% of individuals in a fish population reach sexual maturity. The SL50% method is used to determine the body length and age at primary sexual maturity. Males and females are separated, and body length is divided into 10mm segments. The percentage of mature individuals within a segment relative to the total number of individuals in that segment is the proportion of sexually mature individuals in that segment. The formula is as follows:

[0068]

[0069] P: Percentage of sexually mature individuals within the body length SL range;

[0070] : The average body length at first sexual maturity;

[0071] : The median value of the body length segment;

[0072] k: constant.

[0073] Separate males and females, divide the age into segments based on 1 year, and calculate the proportion of sexually mature individuals in each segment. Then, group the sexually mature individuals by sex.

[0074] The logistic regression of the proportion of mature individuals against age is shown in the following formula:

[0075]

[0076] P: The percentage of age at sexual maturity within age range A;

[0077] : The average age of first sexual maturity;

[0078] A: The median value of the age range;

[0079] k: constant.

[0080] S5: Determining the breeding season and period:

[0081] The breeding season is primarily determined by the development of the gonads. The presence of a certain proportion of stage IV and V gonads in a sample generally confirms the breeding season. Additionally, changes in the sex index of males and females in different months can be used for confirmation; a peak in the index indicates the breeding season. The breeding season is mainly determined by the maturity coefficient of the gonads. The formula for calculating the gonadal maturity coefficient is as follows:

[0082] GSI = (GW / BW) × 100%

[0083] GW: Gonadal weight; BW: Body weight; GSI: Maturity index.

[0084] Based on the distribution of GSI values ​​and gonadal stage composition of samples from different months, an annual variation curve of GSI was plotted to determine the concentrated breeding period, start period, and end period of this fish species.

[0085] S6: Spawning type:

[0086] As eggs develop, their volume continuously increases, and the diameter of eggs varies significantly at different developmental stages. Therefore, egg diameter measurement can be used to determine the spawning type (single-time or batch spawning) in fish. Samples are collected year-round and fixed in 10% neutral formalin. In practice, the diameter of eggs with accumulated yolk in stages III-IV ovaries is measured. Eggs are photographed and preserved under a dissecting microscope while kept moist, and the egg diameter is measured using Imag software. At least 100 eggs are measured per fish. An egg diameter frequency distribution map is plotted to determine the spawning type (single-time or batch spawning).

[0087] S7: High-precision fish reproductive capacity measurement and analysis:

[0088] S701: From the fixed ovary, take tissue samples from the anterior, middle, and posterior segments. After blotting off excess water on filter paper, weigh and count the samples, then mix them and weigh the precise weight (e.g., 0.1g). The relevant calculation formula is as follows:

[0089] Absolute fertility of an individual: ;

[0090] Body length relative to reproductive capacity: ;

[0091] Body mass relative to fertility: ;

[0092] Gonadal maturity coefficient: ;

[0093] plumpness: ;

[0094] Contribution rate: ;

[0095] In the formula, The number of gonadal ovules collected (in ovules); The mass (g) of the gonads taken; Fish ovary mass (g); F represents individual fertility; , where L is the average absolute fertility of individuals in the age group (seeds / tail); L is the individual body length in mm; Net body weight (g); N is the number of samples (tails) in this age group; The total fertility (number of grains) of the fish samples tested.

[0096] S702: Place the sample in a petri dish with a grid, take a picture under a high-definition microscopic imaging system, and use image analysis software to automatically identify and count the number of eggs in the sample for identification and analysis.

[0097] S8: Correlation analysis between fertility model and environmental factors:

[0098] S801: Collect environmental data of the spawning grounds during the breeding season, including water temperature, dissolved oxygen, pH, flow velocity, and substrate type. Perform power function regression analysis on absolute fertility (F) with body length (L), weight (W), and age (A), and select the model with the highest coefficient of determination R² as the best prediction model.

[0099] S802: Use a generalized linear model to analyze interannual reproductive capacity data and key environmental factors for the corresponding year to quantify the impact of environmental fluctuations on population reproductive capacity.

[0100] S9: Population Reproduction Strategies and Vulnerability Assessment:

[0101] S901: Based on the aforementioned age at first sexual maturity, reproductive capacity, egg type, and egg diameter, this species is determined to be an "r-selection" or "K-selection" species.

[0102] S902: Based on its K-selection characteristics of "late maturity and low fertility", a population growth model is constructed to assess its population vulnerability index under fishing pressure or environmental changes, providing a quantitative basis for formulating protection levels and measures.

[0103] Compared with related technologies, the method for identifying and analyzing the reproductive biological characteristics of schizothorax fish in plateau regions provided by this invention has the following beneficial effects:

[0104] This invention provides a method for identifying and analyzing the reproductive biological characteristics of schizothorax fish in plateau regions. It organically integrates all aspects of reproductive biology research into a coherent whole, ensuring the standardization of the research process and the comparability and reproducibility of the results. Through multi-person arbitration for age determination and automatic egg counting via image recognition, it effectively solves the problems of strong subjectivity, low efficiency, and large errors in traditional methods, significantly improving the accuracy of key parameters (such as age and fertility). It mandates the inclusion of quantitative environmental monitoring data in the analysis framework and uses mathematical models to quantitatively reveal how environmental stress affects reproductive success, enabling research results to directly serve the assessment of the impact of climate change on plateau aquatic ecosystems. By introducing life history theory analysis and quantitative assessment of population vulnerability, it transforms biological data into quantitative indicators that can predict population development trends. The resulting results, such as fishing ban periods, minimum catch sizes, and threat levels, can be directly used by management departments, thus achieving efficient transformation of scientific research results into conservation practices.

[0105] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for identifying and analyzing the reproductive biological characteristics of schizothorax fish in plateau regions, characterized in that, Includes the following steps: S1: Sample collection and basic data acquisition: Systematic sampling is carried out in the target water area on a quarterly or monthly basis, covering the complete breeding cycle and different age groups. Biological measurements are performed on the collected samples, including body length, weight, and sex identification, to determine sexually mature individuals. Scales or microotoliths are collected for age identification, and gonads are removed for fixation. S2: Determination of the developmental stages and reproductive cycle of fish gonads: By preparing paraffin sections of gonads and staining them, the morphology of reproductive cells is observed under a microscope. Based on the phase of oocytes, the accumulation of yolk, and the state of follicular cells, the developmental stages of the ovary and testes are accurately divided. S3: Precise age determination and growth relationship establishment: Use a microscope or microscopic imaging system to read the growth rings, have at least two researchers interpret the age data, and conduct relevant growth analysis with body length and weight to establish the Von Bertalanffy growth equation; S4: Primary Sexual Maturity Identification Analysis: Using a logistic regression model, based on the proportion of sexually mature individuals in body length and age segments, the average body length and average age at primary sexual maturity were determined. The formula is as follows: and Where P represents the proportion of sexually mature individuals. Let A be the median value of the body length range, A be the median value of the age range, and k be a constant. The average body length at first sexual maturity. : The average age of first sexual maturity; S5: Determination of Breeding Season and Period: Based on the annual variation curve of the Gonadal Maturity Index (GSI) and the composition of gonadal stages, the peak breeding period, the beginning period, and the end period are determined. The formula for calculating the Gonadal Maturity Index is as follows: GSI = (GW / BW) × 100% Wherein, GW is gonadal weight, BW is body weight, and GSI is maturity index; S6: Ovulation type determination: By measuring the diameter of oocytes in the ovaries from stage III to IV and drawing an oocyte diameter frequency distribution map, the ovulation type can be determined as either a single ovulation or batch ovulation. S7: High-precision fish fertility measurement and analysis: three segments of tissue (anterior, middle and posterior) were taken from the fixed ovary, weighed, and then the number of eggs was automatically identified and counted using image analysis software. The absolute fertility of the individual, the relative fertility of body length, the relative fertility of body weight, the gonadal maturity coefficient, the degree of fatness and the contribution rate were calculated. S8: Correlation analysis between reproductive capacity model and environmental factors: Collect environmental data of spawning grounds during the breeding season, including water temperature, dissolved oxygen, pH value, flow velocity and substrate type. Perform power function regression analysis on absolute reproductive capacity with body length, weight and age. Select the model with the highest coefficient of determination as the prediction model. Analyze the impact of environmental fluctuations on reproductive capacity through a generalized linear model. S9: Population reproductive strategies and vulnerability assessment: Based on the age of first sexual maturity, reproductive capacity, egg type and egg diameter, determine whether the species adopts r-selection or K-selection strategies, construct a population growth model, and assess the population vulnerability index.

2. The method for identifying and analyzing the reproductive biological characteristics of schizothorax fish in plateau areas according to claim 1, characterized in that, In S1, the biological measurements include body length measurement accurate to millimeters, weight measurement accurate to grams, and gonad fixation using formalin or Bouin's fixative.

3. The method for identifying and analyzing the reproductive biological characteristics of schizothorax fish in plateau areas according to claim 1, characterized in that, In S2, the criteria for classifying the stages of gonadal development include: Stage I: The gonads are linear in structure, translucent or pale flesh-colored; Stage II: The ovaries appear as thin threads or flat bands, with no visible eggs, and the testes are thin and thread-shaped. Stage III: The ovaries are enlarged, the eggs are clearly visible but adhered together, and the testes are cylindrical; Stage IV: The ovaries occupy most of the abdominal cavity, the eggs are plump and easily separated, and the testes are milky white; V stage: The eggs mature and flow out; gentle pressure on the abdomen can release either eggs or sperm. Stage VI: The ovary is atrophied and congested, containing empty follicles and degenerated oocytes.

4. The method for identifying and analyzing the reproductive biological characteristics of schizothorax fish in plateau areas according to claim 1, characterized in that, In S3, if the age determination results are inconsistent, the determination shall be made by a third party through arbitration.

5. The method for identifying and analyzing the reproductive biological characteristics of schizothorax fish in plateau areas according to claim 1, characterized in that, In S4, the body length segment is divided into 10mm segments, and the age segment is divided into 1-year segments.

6. The method for identifying and analyzing the reproductive biological characteristics of schizothorax fish in plateau areas according to claim 1, characterized in that, In S7 The formula for calculating the absolute fertility of an individual is: ; The formula for calculating the relative reproductive capacity of body length is: ; The formula for calculating body mass relative to fertility is: ; The formula for calculating the gonadal maturity coefficient is: ; The formula for calculating fullness is: ; The formula for calculating the contribution rate is: ; In the formula, The number of gonadal ovules collected (in ovules); The mass (g) of the gonads taken; Fish ovary mass (g); F represents individual fertility; , where L is the average absolute fertility of individuals in the age group (seeds / tail); L is the individual body length in mm; Net body weight (g); N is the number of samples (tails) in this age group; The total fertility (number of grains) of the fish samples tested.

7. The method for identifying and analyzing the reproductive biological characteristics of schizothorax fish in plateau areas according to claim 1, characterized in that, In step S7, the image analysis software uses automatic recognition technology to count the eggs, with no less than 100 eggs measured per fish.

8. The method for identifying and analyzing the reproductive biological characteristics of schizothorax fish in plateau areas according to claim 1, characterized in that, In step S8, the environmental factor data is acquired through sensors or on-site measurements, and the generalized linear model is used to quantify the effects of water temperature, dissolved oxygen, and flow rate on reproductive capacity.

9. The method for identifying and analyzing the reproductive biological characteristics of schizothorax fish in plateau areas according to claim 1, characterized in that, In S9, the population vulnerability assessment includes calculating a vulnerability index based on K-selection characteristics, which is used to formulate protection levels and measures.

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