Species Diversity Of Understory Medical Plant In Four Kinds Of Typical Secondary Forests In Huang Baiyuan Nature Reserve

Huang Baiyuan Nature Reserve is located in the middle south of Qinling mountain,special geographical location, gave birth to the rich resources of medicinal plants. In order tocontinue the development and utilization of medicinal plant resources, we made HuangBaiyuan Nature Reserve as a study area using the method quadrat survey, conducted fieldsurveys and analysis of the region’s typical secondary forest resources of medicinal plants,aimed at the region development and sustainable use of medicinal plant resources provide thebasis.Through the method of typical sampling, the study investigated understory medical plantspecies diversity of4kinds of typical secondary forests (Pinus tabulaeformis forest, Quercusvaliena var.acuteserrata forest, Q.variabilis forest and Betula albo-sinensis forest) in HuangBaiyuan Nature Reserve by species richness, evenness index, species diversity index andsimilarity coefficient. The results are as follows:The importance value of medical plant in shrub layer of four kinds of secondary forestsreflects the dispersion characteristics. Lespedeza bicolor and Cotinus coggygria were thedominant species in shurb layer of Pinus tabulaeformis forest, the importance value were49.79%and34.46%; Corylus heterophylla and Elaeagnus pungens were the sub-dominantspecies. Litsea pungens and Rubus corchorifolius were the dominant species in shurb layer ofQuercus valiena var.acuteserrata forest, the importance value were38.54%and32.39%;Spiraea salicifolia and Lespedeza bicolor were the sub-dominant species. Q.variabilis and L.glauca were the dominant species in shurb layer of Q.variabilis forest, the importance valuewere42.93%and40.11%; Lespedeza bicolor and Albizzia kalkora were the sub-dominantspecies. Rubus corchorifolius and Rosa multiflora were the dominant species in shurb layer ofBetula albo-sinensis forest, the importance value were97.09%and41.55%; Ribes glacialeand Cerasus tomentosa were the sub-dominant species.There is an obvious differentiationbetween dominant species and non-dominant species of understory medical plant in hurblayer of four kinds of typical secondary forests. Arthraxon hispidus、Dendranthema indicumand Artemisia argyi were the dominant species in herb layer of Pinus tabulaeformis forest, theimportance value were52.03%、25.79%and23.31%. Desmodium racemosum was the dominant species in hurb layer of Quercus valiena var.acuteserrata forest, the importancevalue was58.63%, other herb species importance value more than10%were Agrimoniapilosa and Adiantum capillus. Desmodium racemosum was the dominant species in hurb layerof Q.variabilis forest, Anemone tomentosa and Agrimonia pilosa were the sub-dominantspecies, the importance value were37.33%、28.96%and24.43%. Ligularia sibirica andRodgersia aesculifolia were the dominant species in hurb layer of Betula albo-sinensis forest,the importance value were73.24%and51.66%, Artemisia argyi and Cimicifuga foetida werethe sub-dominant species.There are55species understory medical plant in shurb layer of four kinds of secondaryforests belonging to31genera and48families, there are35species understory medical plantin shurb layer of Pinus tabulaeformis forests belonging to24genera and33families, there are26species understory medical plant in shurb layer of Quercus valiena var.acuteserrata forestsbelonging to19genera and23families, there are29species understory medical plant in shurblayer of Q.variabilis forests belonging to17genera and25families, there are15speciesunderstory medical plant in shurb layer of Betula albo-sinensis forests belonging to11generaand15families. There are66species understory medical plant in hurb layer of four kinds ofsecondary forests belonging to33genera and64families, there are27species understorymedical plant in shurb layer of Pinus tabulaeformis forests belonging to16genera and27families, there are26species understory medical plant in shurb layer of Quercus valienavar.acuteserrata forests belonging to17genera and26families, there are33speciesunderstory medical plant in shurb layer of Q.variabilis forests belonging to21genera and33families, there are17species understory medical plant in shurb layer of Betula albo-sinensisforests belonging to11genera and17families.Richness index and Shannon index of understory medical plant in shurb layer of fourkinds of secondary forests were Pinus tabulaeformis forest> Quercus valiena var.acuteserrataforest> Q.variabilis forest> Betula albo-sinensis forest, in hurb layer were Q.variabilisforest> Quercus valiena var.acuteserrata forest> Pinus tabulaeformis forest> Betulaalbo-sinensis forest; Simpson index and Evenness index of understory medical plant in fourkinds of secondary forests were oak community> Pinus tabulaeformis forest> Betulaalbo-sinensis forest. The medical plant species diversity is that the Betula albo-sinensiscommunity is the lowest and has significant differences with the other three kinds of forests;no obvious difference between Pinus tabulaeformis and oak community.In the four kinds of secondary forests in the shrub layer, the order of the similaritycoefficient: Pinus tabulaeformis forest and Quercus valiena var.acuteserrata forest> Quercusvaliena var.acuteserrata fores and Q.variabilis forest> Q.variabilis forest and Betula albo-sinensis forest> Q.variabilis forest and Betula albo-sinensis forest> Pinus tabulaeformisforest and Betula albo-sinensis forest. In the four kinds of secondary forests in the hurb layer,the order of the similarity coefficient: Pinus tabulaeformis forest and Q.variabilis forest> QuPinus tabulaeformis forest and Quercus valiena var.acuteserrata forest> Q.variabilis forestand Quercus valiena var.acuteserrata forest> Pinus tabulaeformis forest and Betulaalbo-sinensis forest> Q.variabilis forest and Betula albo-sinensis forest> Quercus valienavar.acuteserrata forest and Betula albo-sinensis forest. Species similarity of understorymedical plant in Pinus tabulaeformis forest, Quercus valiena var.acuteserrata forest and Q.variabilis forest is high; there is an obvious species differentiation of Betula albo-sinensisforest and the other three kinds of forests, the similarity coefficient of Betula albo-sinensisforest and the other three kinds of forests is low.Understory medical plant species diversity of4kinds of typical secondary forests in theherb layer is higher than that in the shrub layer. The medical plant species diversity in theshrub layer of the Betula albo-sinensis community is higher, while oak community is higherin the herb layer. Because of in close range of ailitude, ecological factors such ashydrothermal conditions and soil are similar, medicinal plant species richness in the Betulaalbo-sinensis community and oak community is high and they have more common species;Species similarity of understory medical plant in Pinus tabulaeformis forest, Quercus valienavar.acuteserrata forest and Q. variabilis forest is high. The Betula albo-sinensis forestdistributed in a relatively high alpine zone, where has low temperature, high humidity andrelatively simple wild medicinal plant species. The similarity coefficient of Betulaalbo-sinensis forest and the other three kinds of forests is low.Species diversity were studied along an elevation gradient distribution pattern in thePinus tabulaeformis forest and Quercus valiena var.acuteserrata forest, all species wererecorded within each quadrat shrub layer and herb layer composition, coverage and altitude ofeach plot were measured. The results showed that with increasing altitude, species diversity ofthe Pinus tabulaeformis forest increased first before down, humidity and light might be themain reason for this distribution pattern. The results showed that with increasing altitude,humidity increased in the habitat, then species diversity increases, while with increasingcoverage, species diversity decreased as light diminished in the forest. In the1350m and1550m place, species richness of understory medical plant in Quercus valienavar.acuteserrata forest is high, canopy density was large, which had negative growth of thelight-loving medicinal plant species in hurb layer, so understory medical plant speciesdiversity of Quercus valiena var.acuteserrata forests in the shurb layer is higher than that inthe hurb layer. With increasing altitude, species richness of understory medical plant in the 1750m was lower than that in the1550m, the coverage of shurb layer was reduced, whichcaused light to increase, so species diversity of understory medical plant in the herb layerincreased.Slope is the indirect environmental factors which caused understory medical plantspecies diversity indices different. Pinus tabulaeformis and Quercus valiena var.acuteserrataare light-loving species, the sunny slope was benefit to the growth of understory medical plant;Rooting system developing of Pinus tabulaeformis and Quercus valiena var.acuteserrataleaded to strong transpiration, and water status was bad, which had negative growth of themedicinal plant species in shurb layer and in hurb layer, so understory medical plant speciesdiversity in the sunny slopeis higher than that in the shady slope.The survey compared with the2008science investigations in Huang Baiyuan NatureReserve. Because the community itself succession and human disturbance, there is an obviousdifferentiation between dominant species and non-dominant species of understory medicalplant in four kinds of typical secondary forests. Therefore, real-time monitoring of medicinalplant species diversity index is an effective way to understand the current situation ofprotected area resources, which has practical significance for protection and utilization ofmedicinal plant resources.