基于i-Tree Eco模型的城市绿地生态功能与价值评估——以常州市民广场为例

Ecological Function and Value Assessment of Urban Green Space Based on i-Tree Eco Model——Taking Changzhou People's Square as an Example

城市绿地是城市的重要组成部分,具有生态效益、社会效益和经济效益。国内对城市绿地生态功能价值评估方法多样,可比性差。i-Tree Eco模型是现阶段国外应用比较广泛的城市绿地生态功能的评估工具,在我国的应用比较少。文章以常州市市民广场为研究对象,通过随机样点调查法采集样点数据,使用i-Tree Eco模型评估其生态功能与价值,讨论该模型在国内的使用方法。结果表明,市民广场面积约为17.2 ha,乔木覆盖率46.9%,共有树木2 371棵,叶面积为15.3 ha,树木的胸径主要分布在22.9～30.5 cm,总的碳存储量为386.6 t。市民广场内绿地的生态功能为每年净化空气1 443.97 kg,固碳量15.54 t,生产氧气29.30 t,减少地表径流3 775 m3;生态功能价值为每年净化空气价值1.519万元,固碳价值1.532万元,生成氧气价值2.930万元,减少地表径流价值6.148万元。

Urban green space plays an important role in a city for its ecological,social and economic benefits.Assessment methods for urban greening ecosystem services are diverse in China.However,i-Tree Eco model,the tool for ecological function assessment widely used abroad,finds few applications at home.This research,taking Changzhou People's Square as an example,collects the sample data treated with random sampling,and evaluates the ecological function and value using the i-Tree Eco model to explore the assess method in application in China.The result shows that Changzhou People's Square is 17.2ha with 46.9% of tree coverage.There are totally 2371 trees and the leaf area is 15.3 ha.The DBH of trees mainly range from 22.9cm to 30.5cm and the total carbon storage reaches 386.6 tons.Annually speaking,the ecological function manifests itself as air pollutants removal 1443.97kg,carbon seguestration 15.54t,oxygen production 29.30t and runoff reduction by 3775m^3.Repectively,it amounts to the value of 15190￥ by air pollutants removal,15320￥ by carbon sequestration,29310￥ by oxygen production and 61480￥ runoff reduction.