| Ulmus pumila L. is civic tree in Harbin, its crown is wide and it looks beautiful, but its application is affected by easily got pest. Ulmus davidiana var. mandshurica Skv. has narrower crown and is slightly stronger resistant to insect pest than Ulmus pumila L.. Their provenance is the natural vegetation resources distributed in Heilongjiang Province; both ornamental traits both have commonness and also have individuality. Through field research, study both application assessment on green space in Harbin, combining with planting nursery, placing in the road habitat which is differently distant from the road and cultivating them carefully, measuring biomass and other related physiological indicators, evaluating Ulmus pumila L. and Ulmus davidiana var. mandshurica Skv. environmental suitability from different perspective to provide a scientific basis for Ulmus pumila L.By field investigating Ulmus pumila L. and Ulmus davidiana var. mandshurica Skv. application of spatial distribution characteristic, growth conditions in different green habitat, application situation of DBH≥ 60cm trees, landscape application forms cases in spatial composition and public’s perception of beauty on both, evaluating the application results of both from the perspective of historical application. By studying Ulmus pumila L. and Ulmus davidiana var. mandshurica Skv. potted seedlings’ growth, susceptibility, related physiological indicators, photosynthetic characteristic in different environment which has different distance away from the road, comprehensively evaluating Ulmus pumila L. and Ulmus davidiana var. mandshurica Skv. suitability in the road habitat which is differently distant from the road by using principal component analysis and fuzzy subordinate function. To provide the basis for the tone tree species whether recommended for the adaptation under the road habitat. The research results are as follows:1. Ulmus pumila L. could be as the key species in Harbin and was suitable for wide application in the park, road and courtyard green space in Harbin. It was widely distributed different districts and green space in Harbin and grew well in different greenbelts overall. DBH ≥ 60cm Ulmus pumila L. big tree grew healthy in different habitats in Harbin, its cultivated and applied history proved that it could adapt to Harbin climate. Ulmus davidiana var. mandshurica Skv. could be as the backbone tree species in Harbin, only applied in HLJ Forest Botanical Garden. Wether it was applied as the key specie needed further verification in road and park habitats. Ulmus pumila L. and Ulmus davidiana var. mandshurica Skv. were only found in Heilongjiang Forest Botanical Garden at the same place, DBH 40cm-60cm, their growth were both healthy (level 1) in May-June,2014, only had ornamental difference. But limited by the number, it was difficult to judge the adaptation of both big trees.2. Annual Ulmus pumila L. potted seedlings and and annual Ulmus davidiana var. mandshurica Skv. potted seedlings could survive in tested road habitat. From biomass and ornamental quality could meet the basic needs of gardending, could be used as the selection of key tree species in Harbin. Both were shown the best growth quality under the first habitat which was direct light 6 hours, farthest away from the trunk road and minimal traffic. The growth status of both was shown well under the third habitat which was direct light 6 hours, nearest to main road and heaviest traffic. Net growth rate and leaf net growth rate of 1 year Ulmus pumila L. was more than 1 year Ulmus davidiana var. mandshurica Skv. under three different road habitats, proved that former grew better. Under three tested road habitats 1 year Ulmus pumila seedling diseases and insect pests damaged plant percent number and pest harm leaf number was more than 1 year Ulmus davidiana var. mandshurica Skv., indicating that the Ulmus davidiana var. mandshurica Skv. seedlings had higher ornamental quality and stronger resistance to disease and insect.3. Annual Ulmus pumila L. and Ulmus davidiana var. mandshurica Skv. potted seedlings growth quality were different in different environment which had different distance away from the road. With closer to road and heavier traffic, specific leaf weight, leaf relative water content, chlorophyll a+b, Pn and LSP of Ulmus pumila L. decreased as traffic pollution decreased; conductivity, MDA, SOD, POD and LCP increased as traffic pollution increased; specific leaf weight, conductivity, MDA, SOD, Pn, Tr and LCP increased as traffic pollution increased, leaf relative water content, chlorophyll a+b, proline, POD and LSP decreased as traffic pollution decreased. |
PDF Full Text Request