Resource Survey And Protection Of Heritage Trees In Shenzhen City

Based on the systematic investigation of the heritage trees in Shenzhen, the number of species, age structure, flora, spatial distribution, growth performance, health status and the related influence factors were analyzed in this paper. The aim of this thesis is to explore the characteristics and the present situation of protection of the heritage trees in Shenzhen, and provide a reference for the species diversity protection and the ecological environment construction of Shenzhen. The results of the study show that:(1) The types and quantity of heritage trees in Shenzhen are abundant. There are 1 482 heritage trees in Shenzhen City, belonging to 78 species, 62 genera in 35 families and 62 genera. Tropical native trees such as Ficus microcarpa, Cinnamomum camphora, Dimocarpus longan, Litchi chinensis, Celtis tetrandrassp, Bischofia javanica and Antidesma bunius were the main species,besides, it include some the state protection of rare and endangered species such as Cycas pectinata, Aquilaria sinensis and Artocarpus hypargyreus. Heritage trees in Shenzhen has a long history, and have a Pyramid age structure. The average age of the trees is 145.2 a, with the maximum of 1007 a. The tropical distribution type occupies the absolute superiority in the geographical distribution, while a small part is of temperate nature.The distribution characteristics showed obvious tropical nature and the transition from tropical to subtropical and temperate. Among them, the genus Moraceae, Sapindaceae, Lauraceae, Euphorbiaceae, Ulmaceae, Myrtaceae, as the representative of the tropical advantaged families including Moraceae, Sapindaceae, Lauraceae, Euphorbiaceae, Ulmaceae, Myrtaceae and so on constitute the main body of heritage trees.(2) Heritage trees in Shenzhen are widely distributed, and 60% of them distribute in Dapeng New District, Longgang District and Luohu District. The trendhave no relate with the area, population, economic status of the district, but influenced by topography and land utilization. In the Green rich Park green space, and forest area, the number and species are more,while in the plain area,the number of heritage trees is few, and scattered in the side street of a village ora corner of a community, facing the harsh living environment. Thus it can be seen, the park green space and forest area, provide a good environment conditions for the survival of heritage trees, so that it can be mass preservation and continues; and the contradiction of industry development and land use in the process of urbanization is the key factors that lead to the demise of the old trees.the old trees scattered in the city center are in poor living conditions, which should be the key protection object.(3)The growth of plants are affected by geographical environment and site conditions. Most of the heritage trees growth performance is good overall, such as Adenanthera pavonina, Bischofia javanica, Ficus microcarpa and so on. But by the influence of geographical conditions, different parts of the heritage trees growth performance exist certain difference, outside the customs area of the heritage trees growth performance is good on the whole, it is obvious in dominant tree species such as Ficus microcarpa, Cinnamomum camphora, Dimocarpus longan and Bischofia javanica. Most of the old and famous trees in Shenzhen are in good health, but there were 6.75% and 2.50% in poor growth and near death state, it is worth paying attention to. The influence factors of heritage trees in health, in addition to the city environment, but also because of the growth of small environment and management measures of control. The degree of growth point close-to-natural affects the healthy growth of trees, and the tree pool, and building on the tree root confinement measures, has the inhibitory effect on the health of ancient and famous trees. Therefore, priority should be given to the improvment the site conditions on the protection of heritage trees.(4) At present, there are still many problems about the growth and state management of heritage trees in Shenzhen. Affected by the typhoon, termites, man-made destruction, and other unfavorable factors, the trees are under survival threat. First, the land use conflict result in trees’ s survive crisis, because of living space competition, trees are seriously damaged. Secondly, affected by natural factors such as typhoon, the heritage trees ware browed down and their roots were damaged, these are not conducive to the protection of heritage trees. In addition, due to the lack of public awareness and law enforcement, trees were seriously destroyed, causing the decline of certain trees.(5) According to the status quo of the heritage trees, there are some measures to strengthen the protection of heritage trees as follow: The first is to pay attention to the city planning, to handle the contradiction of the protection and development, leaving enough survival space for the trees; The second is to strengthen the legislation, clear and definit the responsibility, and take regular inspection and management, to take appropriate measures for the weakness of heritage trees. The third is to strengthen the propaganda, raise public awareness of the protection and participation, carry out activities related to the protection from multi angle and multi way, in order to promote the healthy growth of the heritage trees in Shenzhen City.