A Comparative Study On The Diversity Composition Of Oribatida On The North Slope And The South Slope Of Changbai Mountain Nature Reserve

Oribatida is a small arthropod that mainly lives in soil.As a decomposer,it plays an important role in the decomposition of soil organic matter,the improvement of soil fertility and the circulation of ecosystem.This paper studies the Changbai mountain nature reserve in the south slope and north slope of 12 different vertical gradient and broad-leaved Korean pine forest,dark coniferous forest,Gao Shanyue birch forest habitats under three kinds of forest Oribatid community composition,analyzes the change to change,vegetation composition change of the slope,altitude and soil physical and chemical properties,and the distribution of Oribatid community diversity.The main research results are as follows:?1?A total of 3656 individuals and 38 species were collected from two research sites in the south slope and north slope of Changbai mountain nature reserve.A total of 1,962heads and 37 species were collected from the south slope of Changbai mountain,and a total of 1694 heads and 35 species were collected from the north slope of Changbai mountain.The dominant species was Lauroppia neerlandica,accounting for 37.76%and43.80%of the species in south slope and north slope respectively.Among them,Damaeus sp.,Peloibates longisetosus and Ceratoppia quaclridentata only appeared in the south slope,and Belba compta only appeared in the north slope.?2?The species abundance increased with the elevation,and the maximum value appeared in the middle and high elevations.The overall trend of species richness was not obvious,but the species composition was the most abundant at 1475 m.The south slope,1475 m above sea level,has the highest abundance,1275 m the lowest,and 1475 m the highest richness.The north slope has the highest abundance of 1675 m,the lowest abundance of 1275 m and the highest richness of 975 m.?3?The diversity index?H'?was the highest at the altitude of 1975 m.The lowest elevation is 1275 m.The index of oribatida diversity?H'?on the north slope of Changbai mountain was the highest at 1475 m above sea level.The lowest elevation is 1275 m.The south slope richness index(D^MG)is highest at 1475 m and lowest at 1575 m.The north slope richness index(D^MG)is highest at 1475 m and lowest at 1875 m.?4?Among the three vegetation zones of broad-leaved red pine forest belt,dark coniferous forest and subalpine birch forest on the north and south slopes,the highest species richness and abundance of a.oribatida was dark coniferous forest,and the lowest was alpine birch forest.?5?The species and soil physical and chemical property indexes?pH,soil bulk density,organic carbon,organic matter,total nitrogen,carbon-nitrogen ratio?were analyzed.The total nitrogen,organic matter and organic carbon values were positively correlated with the number of individual species by comparison with the elevation of1475 m and 1275 m in the south slope.The north slope was 1675 m above sea level and1275 m above sea level.There was no significant relationship between the number of species and the variation trend of soil physical and chemical properties.The distribution of species was most strongly affected by pH,followed by soil bulk density,organic carbon and organic matter.The effect of organic matter and organic carbon on the distribution of oribatida population was similar,but the effect of carbon-nitrogen ratio was the least.Nothrus sp.and Pantelozetes sp.were positively correlated with pH.Achipteria curta was most strongly affected by pH in the north slope,and was negatively correlated with pH,while Euphthiracarus foveolatus and Nothrus anauniensis were positively correlated with pH.Tectocepheus velatus and Nothrus anauniensis were positively correlated with soil density in the southern slope.Bicyrthermannia duodentata and Liacarus borealis were positively correlated with the soil bulk density.?6?Similarity analysis was carried out in the south slope,in the north slope or among the elevations of the south slope and the north slope,and the results showed that species composition was highly different.Among them,Lauroppia neerlandica was distributed in the elevation of 12 sample plots on the north and south slopes,and Nothrus sp.was distributed in the low elevation of the north and south slopes.Belba compta is only distributed at 1675 m on the north slope.Peloibates longisetosus is only distributed in the south slope of 975 m.