The Investigation, Choosing And Application Experiment Of Drought Resistance Landscape Plants In Chongqing

Today,the Urban landscape irrigation of most citys in china is still rely on running water,and utilization of which is very low.It make the limited water resources become more scarce, exacerbating the shortage of urban water resources.Therefore,in order to make the landscaping business better development,it is necessary to change the water use pattern from the"Water-based gardens"to the"Water-saving gardens".Screening the drought-resistant landscape plants is the final means to achive the"Water-saving gardens".The continuable landscape composed by drought-resistant plants is a new trend which is emerging now in landscape garden field all over the world.The meaning of it is using drought-resistant plants resources and less irrigatation or no irrigatation,depend the precipitation to meet the water requirement.At present,the research in screening drought-resistant garden trees and cover plants is much more,but the research in application and configuration mode is inadequate.Though investigation and indoor cultivation and the applicational experiment in Shimen Park.The article propose that the saving-water species. Providing strategic and foundation to the constructing of drought-resistant landscape.The research of indoor cultivation and applicational experiment in Shimen Park show that:The drought-resistant of Crotalaria pallida Aiton,cv.Semperarescens is poorer than other,the others materials have drought resistant in varying degrees.The main research results are as follows:1.Through the investigation in the open field,choosing out 42 kind of drought-resistant plants which commonly appear in open field,such as R.pseudoacacia L.,B.papyrifera(L.)L'Her.ex Vent.,M.azedarach L.and so on.And 44 kind of drought-resistant plants which commonly be used in ubern garden land such as B.purpurea L.,H.mutabilis L.,L.indica L.Briefly introduced the abundance and the drought resistance of those plants.2.The index,such as soil water content,leaf water potential,soil water potential,specific leaf area,transpiration,stomata conduct,growth rate,were selected to measure the drought resistance.The membership function method were used to assesse the drought resistance physiological characteristics of testing plants.The sort of drought tolerance of the ten indor plants is as follow: Vitex negundo L> Dodonaea viscosa(L.) Jacq.> Tephrosia candida DC.> Leaspedeza cuneata> Indigofera amblyantha> Crotalaria pallida Aiton.Pogonatherum paniceum > Pennisetum alopecuroides(L.) Spreng >Polygonum capitatum Ham exD·Don> Erianthusarundinaceus(Retz.)Jesw. In the dispose of serious drought treatment,the soil water content of Vitex negundo L.is stay on 19.85 pencent.And after one cycle drought treatment,the growthtraits of it is well.It shows that the drought-resistant of Vitex negundo is better.In the dispose of feebly arid,the soil water content of Crotalaria pallida Aiton is only 6.32 percent.And the rangeability of soil water potential,specific leaf area is more less than other.The leaf represent wilting and drop off after one cycle drought treatment.After three cycle drought treatment,the growthtraits of Pogonatherum paniceum is well,However,in addition to the comparison which not control water,the other treatment all dead.The sort of drought tolerance of the applicational experiment in Shimen Park is:R. pseudoacacia L.> B.papyrifera(L.) L'Her.Ex Vent.> M.azedarach L.> Koelreuteria bipinnata>Acacia dealbara L.Bush:Vitex negundo L> C.corymbosa L.> Hibiscus syriacus L.> Campylotropi smacrocarpa(Bunge) Rehd.> Pyracantha fortuneana.Grass:Pogonatherum paniceum > Pennisetum alopecuroides(L.) Spreng > Cynodon dactylon L.> Polygonum capitatum Ham ex D Don > Erianthus arundinaceus(Retz.) Jesw.In the drought treatment,Acacia dealbata and Pyracantha fortuneana all represent dead in varying degrees.The growth rate of R.pseudoacacia L.and Vitex negundo is the the fastest and Growth conditions is well.It can be seen that the consequence of assesse using membership function method is Consistent with the Performance of growth.3.Compared with control plot,the height of plants which used in applicational experiment in Shimen Park have no obvious influence on the condition of drought treatment.and the appearance of leaf wilting and dropping off is slightly.In the water-save ascape,It showed that the plants which planted in the open field were more saving water than mesophytes through Calculated.The saved quantity of arbor,bush and grass were 71.5%,71.6%and 72.3%,reaching 70%on the whole.4.Choosing thirteen kind of typical drought-resistant plants through planted in indor and open field.Those plants were recommend to be used in drought-resistant landscape.Arbor:R. pseudoacacia L.,B.papyrifera(L.) L'Her.ex Vent.,M.azedarach L.Bush:C.corymbosa L.,Vitex negundo L,Hibiscus syriacus L,Campylotropi smacrocarpa(Bunge) Rehd.,Dodonaea viscosa (L.)Jacq.,Tephrosia candida DC.Grass:Pogonatherum paniceum,Polygonum capitatum Ham ex D'Don,Pennisetum alopecuroides(L.) Spreng,Erianthusarundinaceus(Retz.)Jesw.Those Plant should Planted in suuny slope,and use the"Arbor-Bush-Grass"patten is more better.The lower deck of arbor and bush should plant those grasses which have shade tolerance.Those drought-resistant grasses can be used in side-slope revegetation,and creat unique charm.Top of the slope can use some high grass such as Erianthus arundinaceus(Retz.) Jesw.Along the slope can plant Pennisetum alopecuroides(L.) Spreng,Polygonum capitatum Ham ex D.Don..Compared with the first two grasses,the shade tolerance of Pogonatherum paniceum is better.5.It showed that using Aquasorb could mitigate the hurt under natural soil drought stress effectively thourgh setting drought seirously and use Aquasorb comparison.Therefore,it is feasible to use Aquasorb properly in revegetation and side-slope revegetationand so on.It can depress the hurt under natural soil drought stress and save water effectively.