Study On The Avian Community Structure And Diversity Of Newly Created Wetlands In Coal Mining Subsidence Area

Coal is an important natural resource for human survival and development.China is a major coal-producing country;coal has made tremendous contributions to China's economic and social development while at the same time it caused serious ecological damages which brought huge negative impacts on the production and life of the mining area and residents around.After the coal mining subsidence,subsided land in areas with a high groundwater level usually sank and formed Water Retention Areas,which made significant changes to the environment.Typical new wetlands in subsidence areas were born due to the destruction and change of the original ecosystem.Wetland plants grew naturally in large quantities and variety in newborn wetlands,and large numbers of new wetland birds that had not appeared before in the original terrestrial farmland ecosystem emerged immediately as newborn wetlands provided them with abundant food resources and a nice habitat shelter,which greatly enhanced the biodiversity of the region.In this paper,the avians of the new wetlands in Baodian mining subsidence areas were studied on community ecology.The new wetlands in coal mining subsidence areas were a unique wetland type formed by the groundwater upwelling and rainwater accumulation after coal mining collapse.It was used as a kind of disaster of coal mining subsidence in the traditional concept,but its formation changed the original terrestrial farmland ecosystem and formed a hotspot area of biodiversity for the biodiversity-poor North China Plain.In the wetland ecosystem,avian is a higher consumer at the top of the food chain that's sensitive to changes in wetland environment.It can be used as an indicator species for environmental changes.Study results of this paper are as follows:(1)From January 2015 to October 2016,a total of 125 avian species were recorded in the new wetlands of subsidence areas and non-subsiding arable lands,belonging to 14 orders and 37 families,including 56 species of transient migrants,27 of resident birds,26 of summer residents,and 16 of winter residents.There were 72 species of non-passerine families in these new wetlands,accounting for 57.6% of all,among which 18 species belonging to Anatidae order and Anseriformes family were the most abundant ones.(2)The species and quantity of newborn wetland birds in different time periods showed obvious seasonal characteristics.The species of migratory birds in spring and autumn were much higher than those in summer and winter,and the number of birds was the most in autumn and winter.The distribution of bird species in different seasons was obvious,and the Sample Plot IV subsiding a longer time in spring had a most complex habitat structure and a highest heterogeneity.The subsidence remnants exposed to the water surface provided nesting sites for common terns.The birds in the summer were mostly non-passerine ones and the new wetlands in different periods distinguished slightly from each other.In autumn,the species of birds was rich and the longest subsiding Sample Plot V had a richest avian species.In winter birds in the north clustered so that there was a larger species and quantity difference.The Shannon-Wiener index and the homogeneity index of birds in newborn wetlands formed in different periods were not significantly different in four seasons(P <0.5),indicating that the collapse time had little effect on bird diversity in newborn wetlands.(3)There were 24 species of birds recorded in the non-subsided area,only equal to 19.2% of the birds recorded in the subsidence areas.Compared with the composition of the avian residential types in the subsidence areas,the non-subsided birds were mainly composed of resident birds,and the seasonal change of species richness and quantity in non-subsided area obviously differed from the change in newborn wetlands.The habitat type in the non-subsided areas was single and lack of heterogeneity,so the non-subsided control farmlands had less species in the same season and there was a smaller difference in bird species between non-subsided plots.The species,quantity and Shannon-Wiener index of the birds in the subsidence area were higher than those in the non-subsided plots,while the homogeneity index of non-subsided farmland was slightly higher.In the non-subsided areas,the bird feeding function group was significantly different from the newborn wetlands.In general,the non-subsided farmland had a relatively single habitat structure and a low avian diversity.(4)A total of 63 species of typical birds were recorded in the typical habitat bird survey of the new wetlands,belonging to 12 orders and 29 families.Totally 26 specials were recorded in the water habitat,mostly composed of wading birds and swimming birds.The Shannon-Wiener index went summer> spring> winter> autumn,and the homogeneity index went summer> spring> winter> autumn;There were 47 species of birds recorded in the wetland plant habitat,including 29 species of non-passerine ones,accounting for 61.7% of the species in this habitat,and the species were mainly composed of small grass songbirds of passerine order and swimming birds of non-passerine order.The species of birds changed significantly by season and the birds were the most abundant species in autumn,followed successively by summer,autumn and winter.The Shannon-Wiener index went summer> spring> autumn> winter and the homogeneity index went summer> spring> winter> autumn.There were 25 species of birds recorded in shoal habitat,which was the least and mainly consisted of shorebirds.The species of birds changed significantly by season and avian species were most abundant in spring,followed successively by summer,autumn and there was no record in winter.The Shannon-Wiener index changed seasonally consistent with the change of species and the homogeneity index went autumn> spring> summer.