建筑垃圾代替砂石配制屋顶绿化基材对比试验研究

Comparative Pot Experiments on Green Roof Growing Media Made from Solid Construction Wastes Substituting for Sand and Stone

建筑垃圾代替天然砂石用于配制屋顶绿化基材,可以取得固废的循环利用和减量化、减少天然砂石开采破坏和缓解城市垃圾围城的压力等诸多好处。但迄今为止,还没有研究探讨建筑垃圾取代天然砂石配制屋顶绿化基材的技术可行性。针对这个问题,采用配比(体积比)为泥炭土(10%)、表土(12%)、复合肥(3g·L^(-1))以及78%的天然沙石或78%碎砖、碎混凝土配制的2种拓展型屋顶绿化基材,并盆栽2种国内流行的屋顶绿化植物佛甲草(Sedum linare)和垂盆草(Sedum sarmentosum),构成2因素(基材和植物)、2水平、4处理、每处理6次重复试验设计;在9个月内3次考察每处理植物盖度,并在试验结束时测试比较每处理植物干重、对比基材全氮、全磷和全钾含量以及每处理基材养分含量的变化。结果表明:2种基材的全磷、全氮和全钾含量变化和其上栽种的2种植物盖度和干重无显著差异;2种基材的全磷、全氮和全钾含量9个月后下降显著;所有处理中,全钾下降比例最大,全氮其次,全磷最少;佛甲草的盖度和干重显著高于垂盆草。研究证实了建筑垃圾能用于配制的拓展型屋顶绿化基材,且可以取得与天然砂石配制的基材一样的屋顶绿化效果。

Solid construction wastes can be used to make green roof growing media for substituting natural sand and stone, by which the solid wastes are recycled, the use amounts of natural sand and stone are reduced,and also the amounts of the wastes in a city are decreased. However, so far no reports have been found on the feasibility of using solid construction wastes to make green roof growing media to substitute for natural sand and stone. In this study, two types of extensive green roof growing media were prepared, which were made of solid construction wastes. Two popular green roof plants （Sedum linare and S. sarmentosurn） were planted in the media to conduct a 9-month-long pot experiment with two factors （plants and media,two levels for each factor） and four treatments （6 repeats for each treatment）. The plant coverage was measured three times during the experiment. At the end of the experiment, plant dry weight, medium nutrient contents （total nitrogen,TN; total phosphorus,TP; and total potassium,TK） and their chan- ges in each treatment were also tested and compared. No significant differences were found in TN,TP and TK contents,as well as the coverage and dry weight of the plants between two media. All medium nutrient contents decreased significantly in nine months with TK dropped the most, and TP the least, and the coverage and dry weight of S. sarmentosum were significantly higher than those of S. linare. The research veri- fied that the extensive green roof growing media made of crushed solid construction wastes could grow green roof plants as good as the media made of natural sand and stone.