North Luo River Stink Bug (pentatomoidea) Species Diversity Of Insects

Pentatomidae is a large group of Insecta.They belong to Hemiptera-Heteroptera.Majority of Pentatomidae are herbivorous species,and most of them are pests in Agriculture and Forestry.In the occurrence period,there are many varieties of the Pentatomidae which decrease crop production.So, the diversity of Pentatomidae has aroused widespread attention.The North Luo River basin is located in the Loess Plateau of the Northern Shaanxi Province,which is one of the most serious soil erosion areas in our country.In recent years,the effect of Grain for Green Program in this area is tremendous.The author had research the diversity of Pentatomidae species in the Northern Luo River basin during May to September in 2008 to provide some basic information for biodiversity conservation,the ecological enviromnent for sustainable development and the control of agricultural pest in this region.This paper has investigated the diversity of Pentatomidae species in the Northern Luo River basin using species abundance,species-abundance model,diversity index,similarity coefficient,PCA,clustering and stepwise regression analysis methods.The results are as follows:1.This investigation has collected 3893 Pentatomidae specimens which subject to 18 families, 63 genera and 74 species.And 17 species were first recorded in Shaanxi Province.Among them,1 genera and 1 species of Gerridae,1 genera and 1 species of Belostomatidae,1 genera and 1 species of Nepidae,2 genera and 2 species of Scutelleridae,20 genera and 24 species of Pentatomidae,1 genera and 1 species of Stenocephalidae,1 genera and 2 species of Urostylidae,1 genera and 2 species of Acanthosomatidae,5 genera and 7 species of Miridae,5 genera and 5 species of Reduviidae,14 genera and 15 species of Coreidae,1 genera and 1 species of Tingididae,1 genera and 1 species of Anthocoridae,1 genera and 1 species of Plataspiddae,5 genera and 6 species of Lygaeidae,1 genera and 1 species of Pyrrhocoridae,1 genera and 1 species of Phymatidae,1 genera and 1 species of Cydnidae.The number of Pentatomidae and Coreidae species is the largest,which occupies 37.73%and 24.35%respectively.The number of Belostomatidae,Nepidae and Stenocephalidae is the lowest,which occupies less than 0.1%.The number of Eurydema gebleri Kolenati and Aeschyntelus sparsus Blote species are the most and Living in an advantageous position in North Luo River basin.In addition,the number of single-genera species of Pentatomidae reached to 55 genera and accounted for 75.34%in the North Luo River Basin.2.Analyzing the number-abundance and species-abundance of Pentatomidae species in different months,sits and habitats.The results show that:The ordination of the number in different months is September＞July～August＞June＞May;the ordination of the number in different sites is Fuxian＞Ganquan＞Zhidan＞Luochuan＞Huangling＞Wuqi.The ordination of the number in different habitats is shrub bushes＞farmland roads＞flood grassland＞streams.The abundance analysis of pentatomidae species shows that the dominant species in different months are different. The seasonal endemic species and common species are rich.And the endemic species are very rich in September.Among the different sits.the number of Pentatomidae species and the endemic species in Ganquan is the largest.Among the different habitats,the Pentatomidae species in the shrub bushes is the most abundant and the number is the largest,while the species distribution in streams is very single.3.Fitting the species-abundance model of different months,sites and habitats.The results show that all accord with Preston's lognormal distribution.The Pentatomidae's dominant and rare species are fewer,and the species in the intermediate state are rich in the North Luo River basin,these explained that this region environment is isotropic and many kinds of multiple species coexist.4.The results of species diversity index analysis in different months,sites and habitats are as follows:(1) the change trend of H' accord with R in different month,and the tendency is direct ratio with a month increase,that is to say,September＞July～August＞June＞May;D_m,H' and R are just the opposite trend;J_sw is September＞May＞July～August＞June.(2) The trend of H' in different locations is Luochuan＞Huangling＞Ganquan＞Fuxian＞Wuqi＞Zhidan;R is Ganquan＞Luochuan＞Huangling＞Fuxian＞Zhidan＞Wuqi;D_m is Wuqi＞Fuxian＞Ganquan＞Zhidan＞Huangling＞Luochuan;J_sw is Luochuan＞Huangling＞Wuqi＞Fuxian＞Ganquan＞Zhidan.(3) The trend of H' in different habitats is farmland roads＞shrub bushes＞flood grassland＞streams;R is shrub bushes＞farmland roads＞flood grassland＞streams.The trend of D_m and H' is just opposite,and the dominance of streams is the highest,which reaches to 0.9709.While the dominance of farmland road is the lowest;J_sw is farmland roads＞flood grassland＞shrub bushes＞streams.The species diversity and abundance of streams are the lowest.And its species-dominance is the highest.But the distribution of species is uniformity.5.The similarity and clustering analysis to the distribution of Pentatomidae species in different months,sites and habitats shows that:(1) the similarity between different months is extremely significant(P＜0.01),and the similarity between June and July～August is the highest,while May and June is the lowest;(2) The similarity between Wuqi and Fuxian is significant(0.01＜P＜0.05), and the similarity between other counties is extremely significantly(P＜0.01).Zhidan and Ganquan is the highest;(3) The similarity of farm roads,shrub bushes and flood grassland is extremely significantly(P＜0.01),among them,the similarity between shrub bushes and flood grassland is the highest,while streams and other three habitats is not significant(P＞0.05).and all shows negatively correlation.6.This thesis analyzed the climatic factors of different sites and Pentatomidae species using principal component analysis(PCA).The results show that the cumulative percent of principal components of climate factors and Pentatomidae species in different sites reach respectively 94.820%and 90.477%,which also occupies mass information and may represent the characteristics of the whole species and climate in this ear.In addition,we list the factor loading matrix of the climatic factors and Pentatomidae species,and the principal component analysis results are very ideal.7.The results of stepwise regression to climate factors and Pentatomidae species show that there are five climate factors of the regression equation.Among them,three factors including the average temperature from May to September,the extreme maximum temperature and the minimum precipitation from May to September are the main obstacles factors that impact on the number and diversity of Pentatomidae species.And another three factors including the highest temperature of May to September,the lowest precipitation of May to September and average annual sunshine hours have a great impact on the numbers,diversity,dominance and evenness of Pentatomidae species.