Investigation of Wild Herbs Based on Three Different Communities

Based on field investigation and statistical analysis, the characteristics of wild herbs in different communities are discussed in this paper. The results showed that there were 32 species and 30 genera of 14 families in the wild herbs of the three communities. Cynanchum chinense R.Br. and Setaria viridis (L.) Beauv are the three community common herbs. Pterocypsela indica (L.) Shih and Cirsium setosum are common to the Cerasus sp. community and Malus micromalus communit. Polygonum, Chenopodium album and Pharbitis nil (Linn.) Choisy are common to the Malus micromalus community and Robinia pseudoacacia L.community.


Introduction
Wild plant germplasm resource is an important part of a region's natural ecosystem.Many wild herbs have good resistance, adaptability and ornamental value in natural condition [1][2][3].By systematically investigating and utilizing the status of the wild plant resources in the study area, the economic development and ecological environment construction can be promoted [4][5][6].In order to find out the difference and connection between different undergrowth herbs, this paper investigated the undergrowth herbs of three plant communities in University of Jinan.

Research Area
The research area is located at the foot of Qinglong mountain, west campus of University of Jinan.The climate is warm temperate monsoon climate, the surface vegetation is mainly deciduous broad-leaved forest, and the soil is brown soil.The main areas surveyed were Cerasus sp., Malus micromalus and Robinia pseudoacacia L.community.

Research methods
The wild herbs from three communities in the study area were investigated from May to July 2018.A large square of 10m*10m was set in three communities respectively.Within the sample cube, herbs were measured with a small sample box of 1m*1m.The species, frequency, coverage and height of herbs were recorded respectively.
Each community was set up with 3 large sample cubes, and 3 small sample cubes were randomly set up within each large sample cube.

Overall situation
This paper investigated the Cerasus sp., Malus micromalus and Robinia pseudoacacia L. community of University of Jinan.The results showed that there were 32 species of herbs, including 30 genera and 14 families.There were 20 species of herbaceous plants in the Cerasus sp.community, and 9 families were involved.The number of species of herbaceous plants in the Malus micromalus community was 13, and the number of families involved was 7. The number of species of herbaceous plants in Robinia pseudoacacia L.community is 9, and the number of families involved is 8. ( Table 1) In the three communities of herbaceous plants, compositae has the largest number of species, up to 13.Secondly, leguminosae, liulaceae, gramineaceae and spinaceae, the number of other family plants are 1(Fig.1.).From Table 2, we can see the herbaceous species of compositae are the largest in the three communities.In the Cerasus sp.community, compositae was followed by leguminaceae, gramineae, and willows.In the Malus micromalus community, the subfamily of compositae is the family spiraceae.In the Robinia pseudoacacia L.community, the distribution of herb species is relatively dispersed.From Table3, we can see the maximum number of herb species is generally concentrated in the frequency 10-30%.As can be seen from Table 3 and Fig. 2, Eleusine indica (L) Gaertn is the herb with the highest average frequency in the three communities, reaching 100%.Secondly, the frequency of six herbs, such as Crepidiastrum lanceolatum (Houtt.)Nakai, Artemisia carvifolia, Setaria viridis (L.) Beauv., Trifolium Linn., Gaura lindheimeri Engelm.et Gray, is 50-90%.The frequency of 5 herbs, such as Pharbitis nil (Linn.)Choisy,Kummerowia striata, Elephantopus scaber L., Gaura parviflora Douglas, Cynanchum chinense R.Br., is 30-50%.The frequency of 13 herbs, such as Pterocypsela indica (L.) Shih, Chenopodium album, Gueldenstaedtia verna, Picris hieracioides Linn., Solanum nigrum L., Boehmeria nivea (L.) Gaudich., Oenothera biennis L., Ipomoea triloba L., Taraxacum mongolicum Hand.-Mazz., is 10-30%.The frequency of 7 herbs, such as Cirsium japonicum, Polygonum, Sonchus arvensis Linn., Commelina communis, Bidens bipinnata Linn., is less than 10%.
In Robinia pseudoacacia L.community, the coverage of Cynanchum chinense R.Br.is 17% only.The coverage of Pharbitis nil (Linn.)Choisy, Setaria viridis (L.) Beauv., Chenopodium album, is 10-20%.The coverage of Boehmeria nivea (L.) Gaudich., Polygonum, Bidens bipinnata Linn., Emilia sonchifolia (L.) DC., is1-5%.And the coverage of Commelina communis is less than 1%.We can see from The frequency and height of Pterocypsela indica (L.) Shih were higher in Cerasus sp.Community, but the change in coverage was not significant in two communities.Cirsium setosum has a higher frequency and coverage in Cerasus sp.community, and a higher height in Malus micromalus community.The height of Polygonum in acacia acacia community was significantly higher than that of Malus micromalus community, while the frequency and coverage of Polygonum changed little between the two communities.The frequency, coverage and height of Chenopodium album and Pharbitis nil (Linn.)Choisy in Robinia pseudoacacia L.community are all greater than Malus micromalus community.

Conclusion
It's a wonderful thing that three different communities has evolved different understory herbaceous plants under the same soil texture, the same time succession and secondary succession after retillage.Plant succession is a so complicated process.We should continue to study it.

Fig. 1 .
Fig. 1.Number of species of each family of herbs.

Table 1 .
Herbaceous conditions in three communities margins.

Table 2 .
Species of each family of three community herbs.

Table 3 .
Frequency distribution of three community herbs.

Table 4 .
Coverage distribution of three community herbs.

Table 5 .
Frequency of herbs common to all three communities.

Table 6 .
Coverage of herbs common to all three communities.

Table 7 .
Height distribution of three community herbs.

Table 5 ,
Table 6 and Table 7, the frequency, coverage and height of Setaria viridis (l.) Beauv are the highest in Malus micromalus community, the middle of Robinia pseudoacacia L.community, and the lowest in Cerasus community sp.The frequency of Cynanchum chinense R.B. was the highest in Malus micromalus community and lowest in Cerasus sp.Community.The coverage and height were highest in Robinia pseudoacia L.community, followed by Malus micromalus community, and lowest in Cerasus sp.Community.