Research On Birds In Agricultural Production Region Of Linfen City And Analysis Of Heavy Metal In Bird Feathers

Birds are an important part of the ecosystem and are highly sensitive to environmental changes and human disturbances.They can choose suitable habitats through active migration.Therefore,birds are often used as indicator organisms to measure the health of a region’s natural environment.Ecological balance of farmland is increasingly becoming the focus of people’s attention.Farmland provides food resources and habitat for birds.While birds enrich the ecological diversity of farmland,they will also cause a certain degree of damage to crops.Use ecological knowledge and science and technology to prevent damage from birds.According to the principle of bioconcentration and biomagnification,the heavy metal content in feathers of birds can be studied to reflect the degree of heavy metal pollution in the area where the birds live.Therefore,this study conducted research on birds resources,bird damage and heavy metal content in bird feathers in Linfen agricultural production region,which can provide certain reference data for environmental protection and sustainable development of crops in agricultural production region around Linfen City.From April 2020 to January 2021,using the variable distance transect method to investigate the bird resources and bird damage in the agricultural production region of Linfen City,and now had a preliminary grasp of the current status of bird resources and the law of bird hazard in the agricultural production areas of Linfen City,At the same time,the heavy metal content of 8 heavy metals in the feather of Cyanopica cyanus in the investigated area was determined and analyzed by the method of AAS and DMA-80 mercury vapourmeter to evaluate the pollution degree of different heavy metals in the agricultural production region of Linfen City was evaluated.The main findings are as follows:(1)According to the topography,geomorphology and habitat characteristics of the theinvestigated area,a total of 12 line transect were laid.After 9 times of investigation by line transect,a total of 110 species of birds distributed in the theinvestigated area in the agricultural region near Linfen City were found.There were a total of 110 species of wild birds in 42 families,18 orders,including 1 species of national Ⅰ-level key protected animals,15 species of national Ⅱ-level key protected animals,and 51 species of key protected animals in Shanxi Province.The bird fauna in the theinvestigated area is dominated by the Palaearctic,which belongs to the Palaearctic,North China,and Loess Plateau sub-regions in the zoogeographical division;the bird residence types are traveling birds,summer migrant birds,and resident birds;the bird Shannon-Wiener index of different habitats was in descending order is wetland>grassland>farmland>plantation>residential area>shrub.(2)The representative Pear Orchard in Chenghuang Village and Apple Orchard in Nanma Village were selected as the orchard survey areas,and the survey method combining line transect and sample points was used to investigate the selected orchards during the ripening period of apples and pears.The investigation on the species,number and characteristics of the birds that harm fruits revealed that the most severely damaged was the pear orchard,with a damage rate of more than 70%.The chief harmful birds were gray magpies(Cyanopica cyanus),gray starlings(Spodiopsar cineraceus),sparrows(Passer montanus),etc;The damage rate of the apple orchard was about 30%,and the chief harmful birds was the sparrow(Passer montanus),the bead-necked turtledove(Streptopelia chinensis),etc;the pear would be also caused secondary damage by insects after being pecked by birds.protecting pear orchards from bird damage requires a combination of bird and insect prevention.The apple orchard suffered less damage and can be controlled by physical methods such as conventional fruit bagging and placement of improved damage control device.(3)According to the planting characteristics of the villages in theinvestigated area,the wheat planting areas in the two villages of Nanma Village and Yandi Village in the investigated area were selected as the sample area.Observe and record the types and numbers of harmful birds in the wheat field,and count the output in wheat yield when the wheat washarvested.The results showed that the main birds that harm wheat fields were sparrows(Passer montanus)and gray starlings(Spodiopsar cineraceus).The decreasing rate of wheat fields yield in Nanma Village was13.5%,and that in Yandi Village was 6.5%.Nanma Village was damaged more severe than Yandi Village.The main influencing factor was the surrounding environment of the wheat field.Governing the surrounding environment of the wheat field is one of the effective methods to prevent and control bird damage in the wheat field.(4)The overall trend of heavy metal content in the feathers of Cyanopica cyanus measured by AAS method and DMA-80 mercury vapourmeter was Zn>Pb>Cr>Cu>Mn>Ni>Cd>Hg,and there was a significant positive correlation between Zn,Pb,and Cr.There was a significant positive correlation between Cr,Mn and Ni.Among the sampling points of the feathers of Cyanopica cyanus,the PCA score of sampling point9 th was the highest,and the PCA scores of sampling points 7th-9th were significantly higher than other sampling points,indicating that the pollution degree of the area around sampling points 7-9 was higher than other sampling points Nearby area.