Responses Of Avian Community Diversity To Different Patterns Of Returning Farmland To Wetland In Naolihe Nature Reserve,Heilongjiang Province

Heilongjiang Naolihe National Nature Reserve is located in the hinterland of the Sanjiang Plain.It is located in the administrative areas of Hongxinglong and Jiansanjiang in the three counties and one city of Baoqing,Raohe,Fuyuan and Fujin,with a total area of 160601 ha.It is very representative in protecting the biodiversity of the Sanjiang Plain and maintaining the function of the ecosystem.After nearly half a century of reclamation,the ecological characteristics of the wetlands in the Naoli River Basin have undergone significant changes.In 2014,the state arranged to carry out pilot projects of returning farmland to wetland in Heilongjiang,Jilin,Liaoning,and Inner Mongolia.The area of returning farmland to wetland was 10,000ha,of which the first batch of pilot projects in Naolihe National Nature Reserve reached 3,004ha.As of 2018,the total area of converted farmland in the Naoli River Reserve has reached 5004ha.This study divides the study area into areas with conversion of farmland and areas without conversion of farmland.From 2015 to 2016 and 2018 to 2020,the line transect method and sample point method were used to compare the Qixing Management Station,Hongwei Management Station,and Shengli Management Station in the Naolihe Nature Reserve.The bird community in the study area of the management station was investigated,and the response of the bird community structure under the two scenarios of different conversion methods and different conversion times was explained in terms of community composition.community diversity and similarity,and then the vegetation community succession was evaluated.The effect of returning farmland to the lower bird community provides a scientific basis for wetland restoration and species protection.The results of the study show that:(1)During the study period,92 species of birds.37 families.16 orders.were observed in the converted farmland to wet areas in the Naolihe Nature Reserve,including 4 species of national key protected birds of the first class and 17 species of national key protected birds of the second class.Species(accounting for 22.83%).Shannon-Wiener index is 3.09.Pielou evenness index is 0.301.The type of bird residence is dominated by summer migratory birds.followed by resident birds and migrant birds.(2)There are temporal and spatial differences in the diversity of bird communities,among which there are seasonal differences in species richness.autumn>spring>summer;bird community diversity is increasing year by year.201 9>2020>2018>201 6>2015.The diversity of bird communities has different habitats.which are expressed as meadow>reed marsh>farmland>natural wetland>natural forestland>marsh meadow>planted forestland.(3)Driven by different methods of returning farmland to wetland.the diversity of bird communities has increased.However,in terms of the abundance of water bird species,the driving influences are inconsistent.The effect of natural returning farmland to wetland is stronger than the effect of human interference.In terms of the abundance of Land birds species,the effect of artificial disturbance of returning farmland to wetland is stronger than that of natural returning farmland to wetland.(4)Driven by different time of returning farmland to wetland,the length of returning farmland has little effect on bird species richness,but in terms of water bird richness,the longer the returning farmland time,the higher the water bird richness.(5)After returning farmland to wetland,the diversity of bird communities in different successional stages of the community is different.The diversity of bird communities in the development stage of succession is higher than that in the initial stage of succession,and the abundance of water bird species is also the same.Further analysis showed that,regardless of human disturbance,returning farmland to wetland or natural returning farmland to wetland,can promote the restoration of bird community diversity.Different ways of returning farmland have different driving effects on the richness of waterfowl and Land birds species.The natural way of returning farmland to wetland is beneficial to the restoration of waterfowl community,and the way of artificial disturbance of returning farmland to wetland is beneficial to the restoration of Land birds species richness.Based on the research results of bird communities driven by the conversion of farmland,suggestions on bird community monitoring and wetland management and protection are put forward.