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Abstract ［Objectives］ This study was conducted to evaluate the value of local Brassicaceae potherb resources in Shiyan City.
［Methods］Seven species of local Brassicaceae edible plants resources in Shiyan City, including Cardamine hirsuta L., Cardamine flexuosa, Cardamine impatiens L., Capsella bursa-pastoris (Linn.), Orychophragmus violaceus (L.) O. E. Schulz, Draba nemorosa L., Rorippa indica (L.) Hiern., were investigated using sampling method, and their value was evaluated.
［Results］ ① Shiyan City was rich in resources of local Brassicaceae potherbs, mostly of which grew in humid areas. ② In the communities of target species, there were 20 species of plants in 19 genera of 15 families in the arbor layer, 19 species of plants in 16 genera from 15 families in the shrub layer, and 58 species of plants in 51 genera from 23 families in the herbaceous layer. The tree, shrub and herb species with the highest dominance Populus simonii var. przewalskii, Robinia pseudoacacia and Chrysanthemum indicum. Local Brassicaceae potherbs in Shiyan City have high edible and medicinal value, especially Cardamine, which has strong selenium-rich ability and is worthy of vigorous development.
［Conclusions］This study provides scientific basis and reference for the development and utilization of local potherbs of Brassicaceae in this area.
Key words Brassicaceae; Wild vegetables; Cardamine; Community structure analysis; Value evaluation
Received: June 3, 2021 Accepted: August 1, 2021
Supported by Hubei Provincial Technological Innovation Special Major Project (2019ABA113); Wuhan Polytechnic University-Deyuan Health Industry Group Academician Expert Workstation Horizontal Project (whpu-2019-cg-138, whpu-2018-cg-041,whpu-2018-cg-140).
Yaowen XU (1998-), male, P. R. China, master, devoted to research about garden plants.
*Corresponding author. E-mail: fyj [email protected]; [email protected].
There are more than about 3 200 species of Brassicaceae plants in 300 genera in the world. They are mainly produced in the northern temperate zone. 425 species, 124 varieties and 9 variants in 95 genera are distributed in China［1］. There are also rich varieties of cruciferous wild vegetables distributed in Shiyan City, mainly including Rorippa, Orychophragmus, Capsella, Cardamine and Lepidium. Among them, Cardamine plants have super-selenium-rich ability and are rich in organic selenium that is easily absorbed by the human body［2］. They are good selenium supplements. Therefore, the importance of studying Cardamine plants is more prominent. Investigating the types and community characteristics of local Brassicaceae wild vegetables is of great significance to the development of their edible, medicinal, and ornamental value. Some scholars have studied the characteristics, application value and cultivation points of genera Lepidium and Eruca of Cruciferae［3］. Chen［4］ investigated the resources of wild cruciferous vegetables in Tianshui City, Gansu, providing a reference basis for the development and utilization of native wild vegetables in Brassicaceae. There are many studies on the selenium-enriching characteristics of Cardamine plants. Studies have shown that the organic selenium in Cardamine violifolia accounts for more than 92% of the total selenium［5］, and it is safe and non-toxic, and can be used as a safe food raw material［6］. Shiyan City is located in the mountainous area of northwestern Hubei, rich in natural resources, and there are few investigations and studies on local cruciferous wild vegetables in the region. In this study, with local Brassicaceae potherbs in Shiyan City as the research object, their species, community species composition, structure, and community characteristics were investigated, and their value was evaluated, aiming to provide scientific basis and reference for the development and utilization of local cruciferous wild vegetables in this area. Materials and Methods
General situation of the research area
Shiyan City is located in the northwestern part of Hubei Province, in the middle and low mountain areas at the northern foot of Wudang Mountain, and on the south bank of the upper and middle reaches of the Hanjiang River. It is known as "the throat of Sichuan and Shaanxi, the thoroughfare of four provinces ". The average annual sunshine time in the area is 1 650-1 960 h; the frost-free period is 224-255 d; the annual average precipitation exceeds 800 ml; and the annual average temperature is 15.0-15.4 ℃［7］. Affected by altitude, slope direction, and other topographical and topographical factors, the climate of the city is complex and diverse. This area is rich in plant resources, with about 1 724 species (including varieties) belonging to 807 genera of 174 families.
Research methods
The sampling method was used to randomly select sample plots in Danjiangkou City of Shiyan City and Zhuxi County where there are more local Brassicaceae potherbs. Six plots were selected in Danjiangkou City and three plots were selected in Zhuxi County. The size of each plot was 10 m×10 m, and the size of plot 1 and plot 4 which are in the special terrain areas was 5 m×20 m. According to ecological research methods, the species composition in the plots was investigated, and the community characteristics were studied. The name, quantity and coverage of plants in each plot were recorded, and the environmental characteristics of plots were recorded, including latitude and longitude, altitude, topography, slope, and aspect. Finally, the survey results were statistically analyzed.
Data processing and analysis
Calculation formulas for quantitative features and calculation analysis formulas of dominance were as follows［8］:
Density (d)=Number of a certain species in the community/Plot area; Frequency (f)= Number of plots that this species appears/Total number of plots; Dominance=Bottom area or total coverage area/Plot area; Relative density (Rd)=(Total number of individuals in a species/Total number of individuals in all species)×100%; Relative frequency (Rf)=(Frequency of a species/Sum of frequencies of all species)×100%; Relative coverage (Rc)=(Coverage of a species/Sum of coverage of all species)×100%; Relative dominance=(Dominance of one species/Dominance of all species)×100%.
The calculation formulas of species importance value［9-10］ were as follows: Important value of trees=(Relative density+Relative frequency+Relative dominance)/3; Important value of shrubs and herbs=(Relative frequency+Relative coverage)/2.
Community coverage evaluation criteria were as follows［11］: bare land: <10%, low coverage: 10%-30%, medium-low coverage: 30%-45%, medium coverage: 45%-60%, and high coverage: >60%.
Analysis on Community Characteristics of Local Wild Vegetables in Brassicaceae in Shiyan City
Basic characteristics of communities
From Fig. 1, it can be seen that the altitudes of communities 1, 2, 3, 4, 5, and 6 were not much different, all ranging from 140 to 160 m. The altitudes of communities 7, 8, and 9 were relatively high, ranging from about 500 to 600 m, and the species richness was proportional to altitude.
Fig. 2 shows the coverage of the herb layer of each community. It could be seen that the coverage of communities 2, 3, 4, and 6 was respectively: 37%, 32%, 31%, and 45%, which belonged to low-medium coverage; the coverage of community 5 was 48%, which belonged to medium coverage; and the coverage of communities 1 7, 8, and 9 was respectively, 68%, 77%, 82% and 89%, which belonged to high coverage, and there were no local Brassicaceae potherbs growing on bare land, indicating that the investigated local Brassicaceae potherbs grow more in areas where there are more herbaceous plants.
Community species characteristics
The survey results showed that the local Brassicaceae potherb communities could be divided into arbor layer, shrub layer and herb layer, of which herb layer plants accounted for the majority. There were totally 98 species of 87 genera in 53 families in the surveyed plants. There were 20 species of trees belonging to 19 genera of 15 families, and 19 species of shrubs belonging to 16 genera of 15 families, and 58 species of herbs belonging to 51 genera of 23 families.
As shown in Table 5, among the tree layer plants, Lauraceae had 3 species in 2 genera, which accounted for 10.53% of the total surveyed genera, and the species accounted for 15.00% of the total surveyed species; each of Rosaceae, Euphorbiaceae and Taxodiaceae had 2 species in 2 genera; and each of other families had 1 species in 1 genera.
As shown in Table 6, in the shrub layer and vine plants, Rosaceae had 4 species in 2 genera, which accounted for 12.50% of the total number of genera surveyed, and the species accounted for 21.05% of the total number of species surveyed; Leguminosae totaled 2 species of 2 genera, which accounted for 12.50% of the total number of genera surveyed, and the species accounted for 10.53% of the total number of species surveyed genera 10.53% of the total number; and each of other families had 1 species of 1 genus. As shown in Table 7, among the herbaceous plants, Asteraceae had the most species, 14 species in total, belonging to 13 genera, which accounted for 25.49% of the total genera surveyed, and the species accounted for 24.14% of the total species surveyed; Brassicaceae plants totaled 7 species of 5 genera, which accounted for 9.80% of the total genera surveyed, and the species accounted for 12.07% of the total species surveyed; Caryophyllaceae plants totaled 5 species of 3 genera, which accounted for 5.88% of the total genera surveyed, and the species accounted for 8.62% of the total species surveyed; each of Gramineae, Lamiaceae and Ranunculaceae had 3 species in 3 genera, which accounted for 5.88% of the total genera surveyed, and the species accounted for 5.17% of the total species surveyed; Papaveraceae had 3 species of 2 genera; each of Fabaceae, Urticaceae, Umbelliferae and Polygonaceae had 2 species of 2 genera; and each of other families had only 1 species.
Importance value analysis
As shown in Table 8, Table 9, and Table 10, the species with the highest importance value of the arbor layer was Populus simonii var. przewalskii, followed by Quercus×leana, both reaching more than 11%, and Phoebe sheareri had the third important value, at 8.25%. The shrub layer and vines showed the highest importance value in Robinia pseudoacacia (11.18%), and Wisteria sinensis had the third most important value (8.83%). The herb layer exhibited the highest importance value in Chrysanthemum indicum, at 9.28%, the second value in Orychophragmus violaceus, at 8.61%, and the third value in Capsella bursa-pastoris, at 7.27%. It could be seen that these species were more distributed in the local Brassicaceae potherb plant communities, with greater dominance. The important values of C. hirsuta, C. impatiens and C. flexuosa were 3.42%, 3.12% and 2.01%, respectively, indicating that that Cardamine had a low degree of dominance.
Value evaluation of local potherbs in Brassicaceae
Local Brassicaceae potherbs had high edible, medicinal and ornamental value (Table 11). Cardamine is rich in selenium, has anti-cancer and anti-oxidant effects［12］, and is worthy of further development and utilization.
Conclusions and Discussion
There were 97 species of plants belonging to 86 genera of 53 families, investigated in the communities of local Brassicaceae edible plants in Shiyan City. Among them, there were 20 species of plants in 19 genera of 15 families in the arbor layer, 19 species of plants in 16 genera from 15 families in the shrub layer, and 58 species of plants in 51 genera from 23 families in the herbaceous layer. Most plants belonged to Rosaceae, Euphorbiaceae, Salicaceae, Leguminosae, Camellia, Compositae, Brassicaceae, Caryophyllaceae, Gramineae, Lamiaceae, etc. Lauraceae plants were the most in the arbor layer, Rosaceae plants were the most in the shrub layer, and Compositae plants were the most in the herb layer. There were abundant water sources by 6 of the 9 communities, suggesting that local Brassicaceae potherbs liked to grow in humid areas, which coincides with the research results of Peng et al.［25］, that is, C. hirsuta liked to grow in humid areas. In terms of species importance, the trees with the highest dominance were: P. simonii var. przewalskii, Quercus×leana, and P. sheareri; the shrubs with the highest dominance were R. pseudoacacia, W. sinensis and T. sinensis; and the herbs with the highest dominance were C. indicum, O. violaceus and C. bursa-pastoris. Among the 9 communities, community 4 had the lowest coverage at 31%, and community 9 had the highest coverage at 89%. The coverage of all communities was greater than low coverage, indicating that the surveyed local Brassicaceae potherbs mostly grow in places covered by a lot of plants. Communities 1, 2, 3, 4, 5, and 6 were located in Danjiangkou City, and communities 7, 8, and 9 were located in Zhuxi County. The average altitude of Danjiangkou City is lower than that of Zhuxi County. The coverage of communities 1, 2, 3, 4, 5, and 6 was lower than that of communities 7, 8, and 9. And the 9 communities were all located in low altitude areas. In this altitude range, species abundance was positively correlated with changes in altitude［26］. Community 8 had the highest species richness at 31, followed by communities 8 and 9. It could be seen that the species richness of higher altitude areas was also higher, which is the same as the research results of Wang［27］, that is, in low altitude areas, the species richness increased with the increase in altitude.
Wild vegetables are rich in nutrients, can provide essential vitamins, protein and trace elements, etc., and can also cure diseases in medicine［28］. The local Brassicaceae potherbs in Shiyan City have high edible, medicinal and ornamental value, and thus great development potential. Among them, Cardamine rich in selenium element［29］ can sever as a good selenium supplement, has high nutritional value and medicinal value, and is worthy of in-depth research and development.
The local Brassicaceae potherbs in Shiyan City are rich in resources and have high usable value, but these high-quality resources is rarely developed and utilized. During the investigation, C. bursa-pastoris is most eaten by locals, and as a fragrant and delicious potherb, there are many practices in the local area. However, most of the local people dont know Cardamine plants, they dont know that that they can be eaten as potherbs or their medicinal value, and Cardamine plants have not become landscaping plants. In view of this, the following suggestions are put forward for the development and utilization of local Brassicaceae potherb resources in Shiyan City: ① it is necessary to complete the investigation of all local Brassicaceae potherb resources and record them in the local flora, so as to provide data support for future research; ② for Cardamine plants, research on artificial cultivation of potherbs with high edible and medicinal value can be carried out, so as to provide technical support for commercial production; and ③ according to different needs, it is necessary to classify and process potherb varieties, use the Internet platform to promote sales, and let potherbs enter the market to drive local economic income. References
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［Methods］Seven species of local Brassicaceae edible plants resources in Shiyan City, including Cardamine hirsuta L., Cardamine flexuosa, Cardamine impatiens L., Capsella bursa-pastoris (Linn.), Orychophragmus violaceus (L.) O. E. Schulz, Draba nemorosa L., Rorippa indica (L.) Hiern., were investigated using sampling method, and their value was evaluated.
［Results］ ① Shiyan City was rich in resources of local Brassicaceae potherbs, mostly of which grew in humid areas. ② In the communities of target species, there were 20 species of plants in 19 genera of 15 families in the arbor layer, 19 species of plants in 16 genera from 15 families in the shrub layer, and 58 species of plants in 51 genera from 23 families in the herbaceous layer. The tree, shrub and herb species with the highest dominance Populus simonii var. przewalskii, Robinia pseudoacacia and Chrysanthemum indicum. Local Brassicaceae potherbs in Shiyan City have high edible and medicinal value, especially Cardamine, which has strong selenium-rich ability and is worthy of vigorous development.
［Conclusions］This study provides scientific basis and reference for the development and utilization of local potherbs of Brassicaceae in this area.
Key words Brassicaceae; Wild vegetables; Cardamine; Community structure analysis; Value evaluation
Received: June 3, 2021 Accepted: August 1, 2021
Supported by Hubei Provincial Technological Innovation Special Major Project (2019ABA113); Wuhan Polytechnic University-Deyuan Health Industry Group Academician Expert Workstation Horizontal Project (whpu-2019-cg-138, whpu-2018-cg-041,whpu-2018-cg-140).
Yaowen XU (1998-), male, P. R. China, master, devoted to research about garden plants.
*Corresponding author. E-mail: fyj [email protected]; [email protected].
There are more than about 3 200 species of Brassicaceae plants in 300 genera in the world. They are mainly produced in the northern temperate zone. 425 species, 124 varieties and 9 variants in 95 genera are distributed in China［1］. There are also rich varieties of cruciferous wild vegetables distributed in Shiyan City, mainly including Rorippa, Orychophragmus, Capsella, Cardamine and Lepidium. Among them, Cardamine plants have super-selenium-rich ability and are rich in organic selenium that is easily absorbed by the human body［2］. They are good selenium supplements. Therefore, the importance of studying Cardamine plants is more prominent. Investigating the types and community characteristics of local Brassicaceae wild vegetables is of great significance to the development of their edible, medicinal, and ornamental value. Some scholars have studied the characteristics, application value and cultivation points of genera Lepidium and Eruca of Cruciferae［3］. Chen［4］ investigated the resources of wild cruciferous vegetables in Tianshui City, Gansu, providing a reference basis for the development and utilization of native wild vegetables in Brassicaceae. There are many studies on the selenium-enriching characteristics of Cardamine plants. Studies have shown that the organic selenium in Cardamine violifolia accounts for more than 92% of the total selenium［5］, and it is safe and non-toxic, and can be used as a safe food raw material［6］. Shiyan City is located in the mountainous area of northwestern Hubei, rich in natural resources, and there are few investigations and studies on local cruciferous wild vegetables in the region. In this study, with local Brassicaceae potherbs in Shiyan City as the research object, their species, community species composition, structure, and community characteristics were investigated, and their value was evaluated, aiming to provide scientific basis and reference for the development and utilization of local cruciferous wild vegetables in this area. Materials and Methods
General situation of the research area
Shiyan City is located in the northwestern part of Hubei Province, in the middle and low mountain areas at the northern foot of Wudang Mountain, and on the south bank of the upper and middle reaches of the Hanjiang River. It is known as "the throat of Sichuan and Shaanxi, the thoroughfare of four provinces ". The average annual sunshine time in the area is 1 650-1 960 h; the frost-free period is 224-255 d; the annual average precipitation exceeds 800 ml; and the annual average temperature is 15.0-15.4 ℃［7］. Affected by altitude, slope direction, and other topographical and topographical factors, the climate of the city is complex and diverse. This area is rich in plant resources, with about 1 724 species (including varieties) belonging to 807 genera of 174 families.
Research methods
The sampling method was used to randomly select sample plots in Danjiangkou City of Shiyan City and Zhuxi County where there are more local Brassicaceae potherbs. Six plots were selected in Danjiangkou City and three plots were selected in Zhuxi County. The size of each plot was 10 m×10 m, and the size of plot 1 and plot 4 which are in the special terrain areas was 5 m×20 m. According to ecological research methods, the species composition in the plots was investigated, and the community characteristics were studied. The name, quantity and coverage of plants in each plot were recorded, and the environmental characteristics of plots were recorded, including latitude and longitude, altitude, topography, slope, and aspect. Finally, the survey results were statistically analyzed.
Data processing and analysis
Calculation formulas for quantitative features and calculation analysis formulas of dominance were as follows［8］:
Density (d)=Number of a certain species in the community/Plot area; Frequency (f)= Number of plots that this species appears/Total number of plots; Dominance=Bottom area or total coverage area/Plot area; Relative density (Rd)=(Total number of individuals in a species/Total number of individuals in all species)×100%; Relative frequency (Rf)=(Frequency of a species/Sum of frequencies of all species)×100%; Relative coverage (Rc)=(Coverage of a species/Sum of coverage of all species)×100%; Relative dominance=(Dominance of one species/Dominance of all species)×100%.
The calculation formulas of species importance value［9-10］ were as follows: Important value of trees=(Relative density+Relative frequency+Relative dominance)/3; Important value of shrubs and herbs=(Relative frequency+Relative coverage)/2.
Community coverage evaluation criteria were as follows［11］: bare land: <10%, low coverage: 10%-30%, medium-low coverage: 30%-45%, medium coverage: 45%-60%, and high coverage: >60%.
Analysis on Community Characteristics of Local Wild Vegetables in Brassicaceae in Shiyan City
Basic characteristics of communities
From Fig. 1, it can be seen that the altitudes of communities 1, 2, 3, 4, 5, and 6 were not much different, all ranging from 140 to 160 m. The altitudes of communities 7, 8, and 9 were relatively high, ranging from about 500 to 600 m, and the species richness was proportional to altitude.
Fig. 2 shows the coverage of the herb layer of each community. It could be seen that the coverage of communities 2, 3, 4, and 6 was respectively: 37%, 32%, 31%, and 45%, which belonged to low-medium coverage; the coverage of community 5 was 48%, which belonged to medium coverage; and the coverage of communities 1 7, 8, and 9 was respectively, 68%, 77%, 82% and 89%, which belonged to high coverage, and there were no local Brassicaceae potherbs growing on bare land, indicating that the investigated local Brassicaceae potherbs grow more in areas where there are more herbaceous plants.
Community species characteristics
The survey results showed that the local Brassicaceae potherb communities could be divided into arbor layer, shrub layer and herb layer, of which herb layer plants accounted for the majority. There were totally 98 species of 87 genera in 53 families in the surveyed plants. There were 20 species of trees belonging to 19 genera of 15 families, and 19 species of shrubs belonging to 16 genera of 15 families, and 58 species of herbs belonging to 51 genera of 23 families.
As shown in Table 5, among the tree layer plants, Lauraceae had 3 species in 2 genera, which accounted for 10.53% of the total surveyed genera, and the species accounted for 15.00% of the total surveyed species; each of Rosaceae, Euphorbiaceae and Taxodiaceae had 2 species in 2 genera; and each of other families had 1 species in 1 genera.
As shown in Table 6, in the shrub layer and vine plants, Rosaceae had 4 species in 2 genera, which accounted for 12.50% of the total number of genera surveyed, and the species accounted for 21.05% of the total number of species surveyed; Leguminosae totaled 2 species of 2 genera, which accounted for 12.50% of the total number of genera surveyed, and the species accounted for 10.53% of the total number of species surveyed genera 10.53% of the total number; and each of other families had 1 species of 1 genus. As shown in Table 7, among the herbaceous plants, Asteraceae had the most species, 14 species in total, belonging to 13 genera, which accounted for 25.49% of the total genera surveyed, and the species accounted for 24.14% of the total species surveyed; Brassicaceae plants totaled 7 species of 5 genera, which accounted for 9.80% of the total genera surveyed, and the species accounted for 12.07% of the total species surveyed; Caryophyllaceae plants totaled 5 species of 3 genera, which accounted for 5.88% of the total genera surveyed, and the species accounted for 8.62% of the total species surveyed; each of Gramineae, Lamiaceae and Ranunculaceae had 3 species in 3 genera, which accounted for 5.88% of the total genera surveyed, and the species accounted for 5.17% of the total species surveyed; Papaveraceae had 3 species of 2 genera; each of Fabaceae, Urticaceae, Umbelliferae and Polygonaceae had 2 species of 2 genera; and each of other families had only 1 species.
Importance value analysis
As shown in Table 8, Table 9, and Table 10, the species with the highest importance value of the arbor layer was Populus simonii var. przewalskii, followed by Quercus×leana, both reaching more than 11%, and Phoebe sheareri had the third important value, at 8.25%. The shrub layer and vines showed the highest importance value in Robinia pseudoacacia (11.18%), and Wisteria sinensis had the third most important value (8.83%). The herb layer exhibited the highest importance value in Chrysanthemum indicum, at 9.28%, the second value in Orychophragmus violaceus, at 8.61%, and the third value in Capsella bursa-pastoris, at 7.27%. It could be seen that these species were more distributed in the local Brassicaceae potherb plant communities, with greater dominance. The important values of C. hirsuta, C. impatiens and C. flexuosa were 3.42%, 3.12% and 2.01%, respectively, indicating that that Cardamine had a low degree of dominance.
Value evaluation of local potherbs in Brassicaceae
Local Brassicaceae potherbs had high edible, medicinal and ornamental value (Table 11). Cardamine is rich in selenium, has anti-cancer and anti-oxidant effects［12］, and is worthy of further development and utilization.
Conclusions and Discussion
There were 97 species of plants belonging to 86 genera of 53 families, investigated in the communities of local Brassicaceae edible plants in Shiyan City. Among them, there were 20 species of plants in 19 genera of 15 families in the arbor layer, 19 species of plants in 16 genera from 15 families in the shrub layer, and 58 species of plants in 51 genera from 23 families in the herbaceous layer. Most plants belonged to Rosaceae, Euphorbiaceae, Salicaceae, Leguminosae, Camellia, Compositae, Brassicaceae, Caryophyllaceae, Gramineae, Lamiaceae, etc. Lauraceae plants were the most in the arbor layer, Rosaceae plants were the most in the shrub layer, and Compositae plants were the most in the herb layer. There were abundant water sources by 6 of the 9 communities, suggesting that local Brassicaceae potherbs liked to grow in humid areas, which coincides with the research results of Peng et al.［25］, that is, C. hirsuta liked to grow in humid areas. In terms of species importance, the trees with the highest dominance were: P. simonii var. przewalskii, Quercus×leana, and P. sheareri; the shrubs with the highest dominance were R. pseudoacacia, W. sinensis and T. sinensis; and the herbs with the highest dominance were C. indicum, O. violaceus and C. bursa-pastoris. Among the 9 communities, community 4 had the lowest coverage at 31%, and community 9 had the highest coverage at 89%. The coverage of all communities was greater than low coverage, indicating that the surveyed local Brassicaceae potherbs mostly grow in places covered by a lot of plants. Communities 1, 2, 3, 4, 5, and 6 were located in Danjiangkou City, and communities 7, 8, and 9 were located in Zhuxi County. The average altitude of Danjiangkou City is lower than that of Zhuxi County. The coverage of communities 1, 2, 3, 4, 5, and 6 was lower than that of communities 7, 8, and 9. And the 9 communities were all located in low altitude areas. In this altitude range, species abundance was positively correlated with changes in altitude［26］. Community 8 had the highest species richness at 31, followed by communities 8 and 9. It could be seen that the species richness of higher altitude areas was also higher, which is the same as the research results of Wang［27］, that is, in low altitude areas, the species richness increased with the increase in altitude.
Wild vegetables are rich in nutrients, can provide essential vitamins, protein and trace elements, etc., and can also cure diseases in medicine［28］. The local Brassicaceae potherbs in Shiyan City have high edible, medicinal and ornamental value, and thus great development potential. Among them, Cardamine rich in selenium element［29］ can sever as a good selenium supplement, has high nutritional value and medicinal value, and is worthy of in-depth research and development.
The local Brassicaceae potherbs in Shiyan City are rich in resources and have high usable value, but these high-quality resources is rarely developed and utilized. During the investigation, C. bursa-pastoris is most eaten by locals, and as a fragrant and delicious potherb, there are many practices in the local area. However, most of the local people dont know Cardamine plants, they dont know that that they can be eaten as potherbs or their medicinal value, and Cardamine plants have not become landscaping plants. In view of this, the following suggestions are put forward for the development and utilization of local Brassicaceae potherb resources in Shiyan City: ① it is necessary to complete the investigation of all local Brassicaceae potherb resources and record them in the local flora, so as to provide data support for future research; ② for Cardamine plants, research on artificial cultivation of potherbs with high edible and medicinal value can be carried out, so as to provide technical support for commercial production; and ③ according to different needs, it is necessary to classify and process potherb varieties, use the Internet platform to promote sales, and let potherbs enter the market to drive local economic income. References
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