Community Componstions And Structrues Of Airfield Arthropods And Grasses With Their Relationships To Birds At Nanjing LuKou International Airport

Exploring the temporal dynamic relationship between airfield birds,insects and grassess helps the control of bird occurrence from a food-chain perspective and the risk reduction of bird-air craft collisions.We monthly sampled airport lawn insects,recorded the airfield bird guild and inspected diets of bird specimens from March to November,2015 and 2017 at Nanjing Lukou International Airport.From May to October of 2015 and A total of 72451 arthropods individuals representing 124 families belonging to 22 orders and 6 classes were collected and identified,inncluding insecta,collembola,arachnida,lipoda,pleuropoda,and malacostraca.Comparing the occurrence between 2015 and 2017,the total individuals in 2017 down to 65.9%of 2015,with above-ground insects decreased by 55.6%and the ground insects decreased by 29.1%.The monthly insect density peaked in September,while the peak of diversity index and richness of grass insect was in July,2017,and the peak of diversity index and richness of ground insect peaked in June and August.However,in 2015,the grass insect density peaked in August,and the peaks of diversity index and richness were in May and August.In addition,the peak of ground insects was in Septem.ber,while the peaks of diversity index arid richness was in October and September.In 2017,the dominant grass insect family was the Tingidae,while Tingidae and Chironomidae dominant in 2015.In terms of ground insect,Labiduridae and Gryllidae dominant in 2017,but in 2015 Formicidae and Labiduridae were the dominant families in 2105.We collected 35213 idividuals of non-insect representing 8 orders and 14 families.Among them,Araneida,Porcellio sp.and Poduridae were the common taxa with larger individuals than other taxa.In the year of 2017,8 orders and 11 families were collected with a total of 8999 individuals;in 2015,there were 8 orders and 13 families and a total of 26,214 individuals.The individuals occurred in 2017 decreased by 34.33%compared to 2015.The monthly occurrence peaked in August both in 2015 and 2017 was August,and the peak of diversity index and richness were in October and Augustin 2017 and.in September and August in 2015.The airfield herbaceous plant community were consist of 80 species belonging to 20 families,with Leguminosae,Compositae and Gramineae the most abundant families.The dominant species were Coreopsis tinctoria Nutt,Trifolium repens L.,Kummerowia striata(Thunb.)Schindland,PersCynodon dactylon(L.)Persoon,Erigeron annuus(L.)Pers,Glycine soja Sieb.The monthly population density change of turfgrass plants in 2017 revealed a uni-model shape.The peak was in August,and the variation of diversity index and richness fluctuate less.The peaks were in September and June respectively.The peak of inter-month population density of turfgrass plants in 2015 was in August,and the peak of diversity index and richness was in October.In the survey of birds in the airport,39 species of birds were recorded-in the area,belonging to 9 orders and 21 families.In terms of residence type,summer migratory birds and resident birds constitute the main body of bird communities in the airport area.From bird species composition,Passerine birds constitute the main body of bird communities in the airport area.The food habits of birds in the airport are divided into carnivorous and omnivorous.The number of birds in the month of 2017 was the highest in August,and the peak of bird diversity and richness was in October.The highest number of birds in the month of 2015 was in September,and the highest peak of diversity and richness appeared in July and May.In terms of the change in the number of species of birds for two years,the number of bird species in 2017 was higher than in 2015 except May and June.Due to the increase in the frequency of bird surveys in 2017,the overall number of birds in 2017 was higher than in 2015,and peaks appeared in August and September.Bird predatory analysis showed that Orthoptera insects and other small arthropods are the main food for carnivorous birds in airports;the food for airport omnivorous birds is insects and other small arthropods,gramineae plants and leguminous plants.There was a significant positive correlation between the number of carnivorous birds and aboveground insects(p=0.034).The diversity index of aboveground insects and bird communities is synchronous with the monthly variation of insects and birds.The results of analysis(R2=0.6434)showed that there was a good correlation between them.The correlation analysis between airport birds and various insects showed that the number of carnivorous birds had a positive correlation with the number of Hemiptera and Orthoptera,especially Hemiptera(p=0.034).This shows that insects on the ground at Lukou Airport are indeed an important factor affecting bird activities,and indirectly lead to the occurrence of bird strikes.There was no significant correlation between the number of carnivorous and omnivorous birds and the number of other small arthropods except insects.In addition,there was no significant correlation between the number of omnivorous birds and various groups of insects.Studies on the relationship between birds and herbaceous plants have shown that,There was a highly significant positive correlation between omnivorous birds and Gramineae plants(p=0.004),but no significant correlations were found between leguminous plants(P=0.332)and Compositae plants(p=0.536).In summary,the relationship indicates that the airport herbs provide food sources and habitats for arthropods.Insects and other small arthropods and grasses provide food sources and habitats for birds.Therefore,it is possible to indirectly reduce the occurrence of birds in airports by controlling the types and numbers of turfgrass plants and insects in airports.