Growth Adaptability Of Garden Trees In Saline-alkali Soil Of Chongming Agriculture Orchard

It is an important item of fully use soil resources and improve economy development that improving and using saline-alkali soil resources in seashore area. So this study was about the saline-alkali soil of the Modern Agriculture Orchard of Chongming in Shanghai. The soil condition, the growth adaptability of garden trees present planted on different salty level soil in the orchard were investigated. The tolerance ability of different kinds of seedling of treest and the effect of soil amelioration on growth of seeding were studied. Above all study will guide the following greening work in Chongming Agriculture Orchard.The content of organic matter, total nitrogen,alkaline nitrogen, valid phosphorus,valid potassium of soil in cultivate layer were determined, compared to average level of coutry, its nutrition characteristic was that nitrogen was deficit, potassium was no deficit, organic matter was moderate, and phosphorus was severely deficit. The orchard have three region, bei liu xiao, bei qi xiao, and bei ba xiao. The content of organic matter, total nitrogen, and alkaline nitrogen of bei liu xiao were higher than bei qi xiao, and then higher than bei ba xiao.The pH and salt content of soil in Chongming Agriculture Orchard were analyzed. Results showed that the pH all of region were more than 8.7, then belonged to heavy alkaline soil. The content of salt of farm soil of bei liu xiao was 0.06%, that of bei qi xiao was 0.13%, and that of bei ba xiao was 0.22%. Furthermore, the salt content of soil beside the road was even higher. Then the three region respectively belonged no salt soil, light degree salty soil, and middle degree salty soil.The viability ratio, survival ratio following several years, and annual average increment of height or diameter of kinds of garden trees were studied. On the no salt soil of bei liu xiao, growth adaptability of Koelreuteria paniculata was best, Sapindus mukurossi and Metasequoia glyptostroboides were better. Rhus typhina, Liriodendron chinensis, Michelis figo, Ginkgo biloba, Acacia farnesiana, Cinnamomum camphora, and Osmanthus fragransadaptability were no good, because of low viability ratio or low survival ratio, and increment of height or diameter were litter.On the light salty soil of bei qi xiao, adaptability of Bischofia polycarpa, Taxodium ascendens, Metasequonia glyptostroboides, Viburnum awabuki, Nerium indicum.Sabina chinensis, Koelreuteria paniculata,Cladrastis wilsonii, Hypericum patulum, Pittosporum tobira, Populus intalia, all were well. And Metasequonia glyptostroboides had a wide limits on adaptability of salt concentration. Only young and little seeding of Trachycarpus fortunei could grow well, but big seedling grew bad. Choerospondias axillaries and Liquidambar formosana could not adapted.Ligustrum lucidum could grow well on light salty soil, but grew bad on middle salty soil.On moderate salty soil of bei ba xiao, Populus americana grew well.Six kinds of garden trees were planted on the different soil region which had different pH and different salt level in Chongming (Bei ba xiao also was a part).Tolerance ability to salt of tree showed that Salix species was best, then was Robinia pseudoacacia, then was 74 Populus and Liriodendron chinensis, Fraxinus bungeana,and Camptotheca acuminate was bad.Seedling of garden trees was soaked in 0-0.5% NaCl solution, and those survival time were studied, different. It showed that tolerance ability to salt was this: Bischofia javanica > Ligustrum lucidum> Koelreuteria paniculata> Cinnamomum camphor a.The amendment of 'Kangdibao' which was used on the moderate degree salty soil had a more obvious effect on raising survival ratio of Populus americana cutting and advancing the growth.