An Investigation And Analysis On The Diversity Of Insect In River Basin Of Shaanxi Province

Small River Basin is a typical complex system in which human sustainable development and regional healthy ecological environment interact with each other.With the rapid development of resources in the River Basin,the ecology and environment health has been seriously affected.As the most important index of the ecological environment of stable insect diversity,the diversity of insect using sweeping net and light trapping in the Dongchuan river basin and Wobaochuan river basin was investigated and studied during July to August in 2019.The study was the first to research the two river basins insect community structure character,alpha-diversity,beta-diversity and the color picture summarizes the insect family level characteristics,meanwhile,selected different environmental monitoring indicator insect.The results are as follows:(1)This investigation has identified 7421 insect specimen and belongs to 19 orders and 213 families.In the Dongchuan river basin,which 1366 insect specimen has identified and subject to 16 orders and 137 families.In the Wubaochuan river basin,which 6055 insect specimen has identified and subject to 16 orders and 190 families.The species proportion of Diptera insect and the number of Hemiptera individuals was the highest.(2)The analysis of the Berger-Parker index showed the dominance index of Dongchuan river basin and Wobaochuan river basin.In the Dongchuan river basin,the order level dominant groups were Hemiptera,Coleoptera,Hymenoptera and Diptera.Family level dominant groups were Lygaeidae and subdominant group was Braconidae.In the Wubaochuan river basin,the order level dominant groups were Hemiptera,Coleoptera,Hymenoptera and Diptera.In the family level,there was no dominant groups and subdominant group was Cicadellidae,Braconidae and Chrysomelidae.(3)The diversity of insect community was conducted by Marglef richness index,Shannon-winner diversity index and Pielou index.The result of insect species richness index show that the Hemiptera,Odonata and Neuroptera in Dongchuan river basin was higher than that in Wubaochuan river basin,while that of Orthoptera,Coleoptera,Hymenoptera and Diptera was lower than that in Wubaochuan river basin.The diversity index of insect groups of Coleoptera,Lepidoptera and Odonata was higher in Dongchuan river basin and Orthoptera,Hemiptera,Hymenoptera,Diptera and Neuroptera were higher in Wubaochuan river basin.The Pielou index of insect community only Hemiptera in Dongchuan river basin was lower than that in Wubaochuan river basin,and other orders were higher than that of Wubaochuan river basin.(4)The insect community similarity index of Dongchuan river basin and Wubaochuan river basin ranged from 0.3 to 0.7 based on the Jaccard similarity cofficient analysis result.There were no extremely similar groups and extremely dissimilar groups between in two river basins.The orders similarity of Lepidoptera and Hymenoptera was proximate the whole insect similarity index of the two river basins among all groups.The insect similarity index and Hymenoptera similarity index of the three branches of Ddongchuan river basin further confirmed that Hymenoptera could be used as an indicator insect for similarity comparison.(5)It was the study of human disturbance factors that,the impact of nature reserves and human activity was positive and negative respectively.The Simpson diversity index show that insect diversity in nature reserves is higher than that in non-nature reserves,the establishment of nature reserves promotes the improvement of diversity.The effect of frequent human activity was terrible.There were more insect species and some less common species found in areas away from human activity.Hymenoptera can be used as a disturbance indicates insects to Indicating human interference.(6)The Ind Val method was used to select the Hymenoptera indicator in two river basins.The Sphecidae and Tiphiidae could be used as environmental indicator insects in Dongchuan river basin,and the Braconidae,Formicidae and Tetracampidae could be used as environmental indicator insects in Wubaochuan river basin.