Determination And Evaluation Of The Stress-resistance Of Landscape Of Plants In Special Space In Lanzhou City

Shade-tolerance ,cold-resistance and pollution-resistance were significant to optimize and allocate ground covers plants and vine in city special space and ecological landscape benefit. The characteristic of fourteen plants were investigated in special space (the shade space under cloverleaf junction and viaduct) and in arboretum in Lanzhou city. Impact of special space on the Chl, and the MDA under stress of lower temperature and SO₂ were studied in the paper.The aim was tried to confirm the ability of shade-tolerance, cold-resistance and pollution-resistance of ground cover plants and vine in special space. The results were as follow:(1) The ratio of Chla/Chlb was a very important index to evaluate the ability of shade- tolerance; the ratio of Chla/Chlb showed positive relationship with the content of MDA, and it was the most important index to evaluate the ability of Stress-Tolerance.(2) The content of Chla of plants in the special space were ranging from 0.33～1.82mg·g^-1. The content of Chlb were ranging from0.31～1.66 mg·g^-1, the content of Chla and Chlb were ranging from 0.64～3.48 mg·g^-1. The ratio of Chla/Chlb were ranging from 1.04～1.48. The content of Chla of plants grown in arboretum were ranging from 0.14～1.19mg·g^-1. The content of Chlb were ranging from 0.12～1.10 mg·g^-1,the content of Chla and Chlb were ranging from 0.27～2.30mg·g^-1. The ratio of Chla/Chlb were ranging from0.78～1.18. The ratio of Chla/Chlb of plants in special space decreased ,that showed plants had good ability of shade tolerance. The ratio of Chla/Chlb of Parthenocissus quinquefolia in different special space were ranging from 1.10 to 1.11, the date indicated that the average ratio of Chla/Chlb of plant in different special space was more consistent and stable. The ratio of Chla/Chlb was reliable and exact index to evaluate the ability of shade-tolerance, and it was key index to introduce and choose plant in the area.(3) MDA of vine under the stress of lower temperature showed the variation was 0.60～3.68μmol·g^-1; the variation of MDA of Parthenocissus quinquefolia was the smallest,indicated the strongest cold-resistance in 6 species. The variation of MDA of Cynanchumchinese was the largest,indicated the weakest cold-resistance. MDA of ground cover plants under the stress of lower temperature showed the difference was 0.26～1.26μmol·g^-1μmol·g^-1. The variation of MDA of Achillea alpina was the largest, indicated the weakest cold-resistance in 7 ground cover plants; the MDA of Crassulaceae was the smallest showed the best capacity of cold-resistance.(4)The variation of MDA of vine under two SO₂ concentration was 0.26～4.25μmol·g^-1; Euonymus forthunei Minus had the lowest variation (0.26μmol·g^-1),Lonicera japonica had the highest variation(4.25μmol·g^-1). It showed the Achillea alpina was the worst population- resistance species. The variation of ground cover plants was 0.07～1.26μmol·g^-1,the Sedum spectablile'StarDust'0.07μmol·g^-1, S.hybridum'Immergrunchell'0.30μmol·g^-1,Sedum bulbiferum 0.33μmol·g^-1;the Crassulaceae had the best performance of population-resistance.(5) The order of relative cell membrane permeability and damage rate of vine under two SO₂ concentration was Lonicera japonica > Cynanchumchinese > Parthenocissus semicordata>Parthenocissus quinquefolia>Hedera nepalensis var.sinensis>Euonymus forthunei Minus. The data showed:Euonymus forthunei Minus had the best performance under pollution in 6 vine species.The order of relative cell membrane permeability and damage rate of vine under two SO₂ concentration was Achillea alpina>Coronilla varia>Viola philippica > Hosta plantaginea > S.hybridum'Immergrunchell'> Sedum bulbiferum > Sedum spectablile'StarDust'. Crassulaceae had the best performance under pollution in 7 ground cover plants.