Plant Diversity And Its Ecosystem Services In The Southern Mountainous Area Of Jinan,China

Jinan is a spring and community symbiotic city with distinct natural geographical and cultural characteristics.The southern mountain area is an important water source and biodiversity hotspot in Jinan City.It is important to study plant diversity and its ecosystem services across different plant communities and sites for establishment of ecological protection policies and ecological compensation mechanisms in this area.In this study,12 survey sites were sampled from the southern mountainous area,and total 72 plots of 10 m X 10 m were set up.Through field investigations,the plant species diversity and its ecosystem service value of each plot were preliminarily determined.The types of plant communities and their species composition in the southern mountain area have revealed a distinct spatial pattern.The spatial pattern of species diversity and its service value across different communities and sites have been discovered.Furthermore,the main ecological factors affecting species diversity and its service value have been discussed to suggest ecological protection,ecological compensation and ecological construction.The results showed that:226 species of 156 genera and 72 families in all investigated sites of the southern mountainous area were recorded.Totally seven associations including Ginkgo biloba-Buxus sinica-Chenopodium album,Castanea mollissima-Ailanthus altissima+Euonymus alatus-Ruta graveolens,Ziziphus jujuba-Forsythia suspensa-Phragmites australis,Koelreuteria paniculata-Grewia biloba-Deyeuxia arundinacea+Dioscorea opposita,Juglans regia.-Vitex negundo+Ziziphus jujuba-Arthraxon hispidus,Robinia pseudoacacia-Rubus crataegifolius-Deyeuxia arundinacea,Platycladus orientalis-Vitex negundo+Lespedeza bicolor-Arthraxon hispidus+Deyeuxia arundinacea have been distinguished.Among the associations,the Shannon-Wiener index,Simpson index,and Pielou index of the association Castanea mollissima-Ailanthus altissima+Euonymus alatus-Ruta graveolens were the lowest,and the various diversity indexes of the association Juglans regia.-Vitex negundo+Ziziphus jujuba-Arthraxon hispidus were relatively higher.The differences of the four diversity indexes between the association.Juglans regia.-Vitex negundo+Ziziphus jujuba-Arthraxon hispidus and the association Platycladus orientalis-Vitex negundo+Lespedeza bicolor-Arthraxon hispidus+Deyeuxia arundinacea were significant.Hongye Valley had the highest Shannon-Wiener index among the 12 survey sites.Among the environmental factors,Pearson correlation analysis and Canonical Correspondence Analysis(CCA)showed that total nitrogen in the soil was significantly positively correlated with the elevation of the plot and total phosphorus in the soil,and significantly negatively correlated with the soil pH.Whereas,the Shannon-Wiener index and Patrick richness index were significantly negatively correlated with soil salinity.Using the modified plant species diversity ecosystem service value assessment formula,it is found that among the seven community types,the association Ziziphus jujuba-Forsythia suspensa-Phragmites australis had the highest biodiversity service value per hectare,followed by the association Juglans regia-Vitex negundo+Ziziphus jujuba-Arthraxon hispidus.Among the 12 survey sites,the Hongye Valley has the highest biodiversity service value per hectare.The main findings of this study are expected to shed light on determining the prior areas of plant diversity protection,the plant diversity target o ecological restoration and the amount of ecological compensation in the southern mountainous area of Jinan.