Population Characteristics And Life Histories Of Aquatic Insects The Based On Body Size-area

Objective: Body shape is a basic characteristic of animals,which is of great significance to the survival,reproduction,distribution and other physiological and ecological aspects of animals.Usually measuring individual size parameters for age and biomass,etc.The study attempts to use area-based individual size to present the population characteristics and life history process of aquatic insectsMethod: Two small but very different species of Baetiella macani and Alainites lingulatus in Pangxie Stream and the larger Ameletus daliensis in Qingbi Stream were selected as research objects.Baetiella macani and Alainites lingulatus were collected on the upper,middle and lower parts of Pangxie Stream from 2017 to 2018,and monthly samples,and monthly samples were collected on the Ameletus daliensis from Qingbixi from January 2021 to January 2022.Thermometers were also installed in both streams.Based on the method of individual area automatically measured by digital image computer,the relationship between population density and population area and their life history traits of the three species was explored by constructing a dynamic map of area frequency combined with the effective accumulated temperature method for life history verification.Results:1.There was a significant linear correlation between population density and population area of the three aquatic insects with different body types.The larger individuals of the Ameletus daliensis have the highest biomass,and the Ameletus daliensis can compensate for interspecific differences caused by low density by adjusting individual area.2.The correlation between the average area and average density of Baetiella macani,Alainites lingulatus,and Ameletus daliensis are significant in terms of temporal dynamics,which overestimates the population role of the Ameletus daliensis in March,April,May,June,July,and August,and underestimates the role of other months in the population3.In terms of temporal dynamics,there is no difference in the average area and density of Baetiella macani,while there is difference in the average area and density of Alainites lingulatus and Ameletus daliensis,but the difference between months can be reduced by adjusting the area.4.The average density and area of the Ameletus daliensis have differences between sample points,but the correlation between the average density and area is significant between sample points.5.The average density and average area of aquatic insects can exhibit population characteristics under the spatiotemporal distribution pattern,and the correlation between average density and average area is significant.Therefore,average area can be used instead of average density to study population structure.6.Ameletus daliensis was a univoltine insect,and the required effective accumulated temperature was 890℃-2534℃.Alainites lingulatus was a bivoltine insect,with a winter generation and a summer generation,the accumulated temperature required by the winter generation was 1954℃,and the effective accumulated temperature of the summer generation was 757℃.The Baetiella macani was determined to exhibit trivoltinism,having an overwintering generation and two summer generations,the effective accumulated temperature required for the winter generation was 1286℃,while the effective accumulated temperature for the first summer generation was 757℃,the appearance of juveniles in the second summer generation overlaps significantly with the first generation.Conclusion: The population area and population density can be used to present the population structure,reflecting the differences between species and different environments,such as times and spaces within species;the monthly dynamic graph constructed by body size-area is suitable for studying the life history of aquatic insects.