城市森林总量需求与实现途径：以徐州市为例

城市森林的功能—需求可以划分为全球气候、市域国土安全、市域公共安全、基本生活环境和高级精神需求5个关系域,其中碳平衡需求是确定1个城市森林需求总量的主要因子,居民生活水平和森林类型结构的变化对城市森林总量需求影响极大。现行城市绿地（城市森林用地）标准可以满足人年均消费1万元对城市森林总量的需要,当人均年消费1.7万元以上时,（理论上）森林覆盖率需要50%以上。仅靠增加城市森林总量来满足居民生活水平不断提高所带来的高碳排放是难以实现的,必须在增加城市森林数量、改善城市森林结构、提高城市森林质量的同时,增加对市区外辖县森林建设的投入。

The total demand and realization approaches of urban forest in Xuzhou City

The function-demand of urban forest can be divided into five relationships i.e.global climate,urban land security,public security,basic living circumstances and advanced spiritual needs.The demand of carbon balance is the major factor to decide the total demand of urban forest.Residents＇ living level and the change of forests＇ structure have extremely huge effect on the total demand of forest.Current urban green space（urban forest land） indexes can meet the total needs of urban forest when the annual average consumption of the city is about 10 000 yuan.However,when the annual average consumption achieved 17 000 yuan,the coverage rate of urban forest must be above 50%.We can hardly achieve the goal if increasing total urban forest only to meet high carbon emissions which is brought by improving standards of residents＇ living level.We must increase the investment of suburb forest construction and the quantity of urban forest,as well,to improve the urban forest structure and ameliorate the quality of urban forest.