Study On Introduction And Assessment And Application Of Ground Cover Plants In Bashang Plateau In North China

The ground cover plants relying mainly on perennial root flowers was employed more and more extensively in urban landscape, they play important roles on maintaining the ecological balance and abounding the landscape garden. The study was representative with Bashang in Hebei, faced the problems of shortage in urban greening variety, short greening stage, flowering season concentrated in the summer, no florescence in spring and autumn, and bare ground leading wind and sand, on the foundation of investigating and analysising application of urban landscape plants and concrete problems, we trans-regional to go to Baoding city to introduction nine Ground cover plants into Zhangbei research station, They were chinese peony(Paeonia lactiflora),hemerocallis(Hemerocallis middendorffii),hemerocallis stella deoro(Hemerocallis fuava), aster(Aster novi-belgii L.), sedum spectabile(Sedum spectabile), Lily(Lilium brownii var. viridulum), hosta(Hosta plantaginea), balloonflower(Platycodon grandiforus). The research focus observed introduced plants of grow and development in introducing region, analyzed and compared adaptability of cold-resistance, carried on application quality assessment of ground cover plants by contrast to common plants in Bashang plateau in north china. The results showed that:Tthrough investigative research of ornamental plants application in typical urban in Bashang plateau, the result showed that there were 57 species applied in regional urban landscape, distributed in 21 families. Tree, shrub, ground cover plants area ratio was 52.3%, 16.0% , 31.7%. native trees have been widely applied,but the shrubs and ground cover plants occupied low percentage among all the landscape plants, so the garden landscape was characterized as single–layer arbor. Garden situation by the side of roads and in the yard of enterprises measured up to the national lowest standard, and in the populated country was lower by 21.6% and 5.0% than the national standard. Base on the cold and arid climate, garden greening stage was only 110～140 d , florescence was three months and a half, and vegetation coverage droped down 5%～12% in winter and spring. Shortage region ground cover plants directly decreased the ecological effect for fixing soil. Through Observation on the growth and development of introduced plants in experiment area, the results show that introduced plants could grow normally and showed good ornamental characteristics. Their phenology have been delayed by 35～60 days. According to the local climate characteristics, measured by crop growth period, the introduced plants, with long florescence, strong coverage which to some extent, expand the region's green period covered and the view of flowering.Through observations on their natural growth conditions and growth morphology and demonstration tests of artificial low-temperature stress root cold physiological changes and physical growth of strain recovery validation studies, the results show that 0 ~ -18℃low temperature processing ,the relative conductivity, soluble sugar and proline contents of nine perennial ground cover plants were all on the rise, while In the -18℃~ -36℃processing, soluble sugar and free proline contents of balloonflower, hemerocallis stella deoro remained rise after fall, The hosta, aster, lily showed continuous downward trend. Combination of winter cold stress, sexual and physical strain to restore growth status showed that nine perennial ground cover plants could be Successful overwintering in North China, Basis of resistance to the cold, The orders were balloonflower, hemerocallis stella deoro, hemerocallis, peony, Eight treasures red-spotted stonecrop, hosta, aster, lily.Based on the research of growth and development characteristics and cold-resistance, research of application of quality assessment fully integrated greening stage, florescence of ground cover plants and ecological requirements, and applied AHP to assess qualitative and quantitative application quality. The actual assessment results show that twenty ground cover plants were divided into four grades according to integrated assessment index. The first level was mainly perennial herb, Such as Chinese peony, hemerocallis,hemerocallis stella deoro, sedum spectabile. They can be used as the best plants of alpine area in North China applying in large-area. The second level is mainly perennial herbs and self-seeding biennial flowers, such as wereballoonflower, aster, lily,common cosmos,corn poppy. This level may serve as a regional backbone plants. The third level was the main of biennial flowers, such as tagetes erecta, petunia hybrida, dianthus chinensis.Fourth grade is used for annual and biennial flowers. Such as Salvia, calendula, maidenhair, gladiolus, dahlia.This type needed artificial overwintering or transplanting. Because of their high cost of greening, this level can be used as decorative-type plants for flowerbed or application in high-grade recreation areas. Application quality classification of twenty ground cover plants provided a scientific theory for Gardening application in North China.