武汉钢铁公司厂区绿地绿量的定量研究

针对城市绿地结构复杂、破碎化程度高的特点，在武汉钢铁公司厂区园林绿地层片结构及其盖度调查的基础上，借助GIS对其绿量进行了定量研究.结果表明，不同生活型植物的单叶面积和叶面积指数差异较大，植物种的叶面积指数大小不仅取决于单叶面积，而且取决于树冠的冠形和枝叶的密集程度.该厂区园林绿地的平均叶面积指数为7.75，总绿量为1 694.2 hm².其中，乔-灌-草型和乔 灌型绿地的面积和绿量分别占厂区总绿地面积和总绿量的79.7%和92.3%，反映了该厂区绿化以乔木为主，乔-灌-草型和乔-灌型绿地类型占绝对优势.结构单一的纯草坪型绿地在厂区应用较少，但草本层片的绿量占总绿量的22.9%.园林绿地的绿量取决于绿地面积、绿地的层片结构、不同层片植物的叶面积指数及其盖度.城市园林绿地应在扩大绿地面积的基础上，尽量选择叶面积指数较高的树种，完善层次结构，以增加总体绿量.以层片作为基础定量单元，在各层片代表种叶面积指数测定的基础上，通过绿地群落类型的层片结构及其盖度调查，并借助遥感影像和GIS提取各类群落的面积，可较为准确地定量城市园林绿地的绿量.

Green space vegetation quantity in workshop area of Wuhan Iron and Steel Company

Aimed at the complex community structure and higher fragmentation of urban green space,and based on the investigation of synusia structure and its coverage,this paper studied the vegetation quantity of ornamental green space in the workshop area of Wuhan Iron and Steel Company,with the help of GIS.The results showed that different life forms of ornamental plants in this area had a greater difference in their single leaf area and leaf area index(LAI),and the LAI was not only depended on single leaf area,but also governed by the shape of tree crown and the intensive degree of branches and leaves.The total vegetation quantity was 1 694.2 hm~2,with the average LAI being 7.75,and the vegetation quantity of arbor-shrub-herb and arbor-shrub communities accounted for 79.7% and 92.3% of the total,respectively,reflecting that the green space structure was dominated by arbor species and by arbor-shrub-herb and arbor-shrub community types.Single layer-structured lawn had a less percentage,while the vegetation quantity of herb synusia accounted for 22.9% of the total,suggesting an afforestation characteristic of "making use of every bit of space" in the workshop area.The vegetation quantity of urban ornamental green space depended on the area of green space,its synusia structure,and the LAI and coverage of ornamental plants.In enlarging urban green space,ornamental plant species with high LAI should be selected,and community structure should be improved to have a higher vegetation quantity in urban area.To quantify the vegetation quantity of urban ornamental green space more accurately,synusia should be taken as the unit to measure the LAI of typical species,and the synusia structure and its coverage of different community types should be investigated with the help of remote sensing images and GIS.