Evaluation And Selection Of Native Tree Species On Urban Forest In Hebei Province

With economic development, the process of urbanization has speeded up in China. However, the issue of urban ecological has become more obvious in the course of China's urbanization. The urban forest played an important role in solving the urban ecological problems. Some studies showed that the tree species used in urban forest were seriously single, and suggested to make full use of native tree species to change the simple urban forest structure and the single composition of species. At present, most of the species selection is still confined to the basic principles and empirical level, but more in terms of landscape aesthetics function of this index. It is very unfavorable to bring into play the comprehensive functions of urban forests. Therefore, the establishment of an objective and scientific method for selecting tree species to enrich urban forest tree species selection and the selection of plant materials have some practical significance.Based on the local species in hebei province as the research object .The State of Utilization about native species in urban forest of Hebei Province was analyzed in this paper. Using AHP (Analytic Hierarchy Process, AHP method for short) theory and methods, the Preliminary Evaluation system of woody plants in Hebei Province was established, and evaluated the woody plants in Hebei Province primarily, from which the woody plants with high scores and unused were singled out. According to the distribution of tree species, from south to north Hanwang Mountain, Baishi Mountain and Wuling Mountain were selected as the survey sites. The Wild Woody comprehensive evaluation system in Hebei Province was constructed using the AHP method. The results are as follows:1 Through statistical analysis on datas, 356 kinds of woody plants has been applied in urban forest in Hebei Province, and there are 168 kinds of native tree species. Among the urban green plants, native woody plants accounted for 47.19%, which accounted for 33.94% of woody plants in Hebei Province. The results showed that native plants in Hebei Province were in the low utilization rate, and native plants should be increase utilization.2 By analysis of the composition of native tree species and genus that have been applied on the production showed that: Rosaceae, Salicaceae, Leguminosae, Oleaceae, Ulmaceae and Caprifoliaceae accounts for 58.33% in all the use of native species production in Hebei Province, and the maximum utilization of plants belongs to Rosaceae, accounting for 20.24% in all the use of native species. Most families have only developed 2 to 5 species, so plants of Rosaceae have an absolute advantage in the use of native species in Hebei Province. The production performance of native tree species are mostly concentrated in few species in Hebei Province, which accounted for 48.21% in the total number of species using for production.3 According to field survey, combined with literature data and expert opinions, 15 evaluations were selected and the Wild Woody comprehensive evaluation system was constructed using AHP. The Comprehensive Assessment System results showed that: in the standard test layer, the resistance in the weights was the largest, accounted for the resistance of woody plants took the most important position in the selection of urban forest; secongdly was biological indicators, when the woody plants used in urban forest which should be considered as key factors. In the target layer, adaptability, resistance to pests and diseases, anti-pollution and the distribution were stronger than the other indicators. Those were important indicators impacting the comprehensive evaluation system of woody plants and can be considered as important indicators in species selection.4 33 species of wild woody plants in Hebei Province were evaluated using Wild woody plants Integrated Assessment System. Higher scores in the evaluation of Rhus chinensis, Ulmus lamellosa, Ulmus laciniata, Rubus parvifolius, Cotoneaster zabelli, Ostryopsis davidiana: Ulmus lamellosa, Cotoneaster zabelli, Ostryopsis davidiana more suitable for acidic soil, Rhus chinensis more suitable for alkaline soil conditions, Ulmus laciniata and Rubus parvifolius relative to the other four plants can be the adaptability of the soil for more acidic or alkaline soil.