北方低温条件下沼渣资源化培育佛甲草的应用研究

Application of cultivation of Sedum lineare Thunb with biogas residue resources under low temperature condition in North China

为克服厌氧发酵沼渣中碳氮磷比严重失调、可生化性差、总氮和总磷浓度高等难以直接资源化利用的难题,同时为北方秋冬季节低温条件下海绵城市建设过程中推广绿色屋顶提供技术支撑,通过调节基质中本地砂质壤土与厌氧发酵沼渣的比例,在北方秋冬季节室外培育佛甲草并研究其生长状态。结果表明:沼渣显著降低了基质的容重,减轻了屋顶的承受负荷;增大了基质的孔隙度,更适宜佛甲草根系下扎生长。基质中添加沼渣改善了低温条件下佛甲草的生长状况,增加了佛甲草的株高和覆盖度,提高了其分蘖能力及叶绿素总量;品质评价得分均高于6分,表明佛甲草的生长基本正常;低温条件下,沼渣和砂质壤土按4∶5混配后的基质培育出的佛甲草综合品质最优。

In order to overcome the difficulties of direct resource utilization resulted from the C/N/P ratio imbalance, poor biochemical degradability and high concentration of TN and TP in anaerobic fermentation biogas residue, and to provide technical support for promoting green roof in the sponge city construction under low temperature environment in northern China, the proportion of sandy soil and biogas residue in the substrate was adjusted to cultivate Sedum lineare Thunb and the growth state observed. The experimental result indicated that the biogas residue reduced the bulk density, lightened the roof loads, increased the porosity of matrix and improved root penetration of Sedum lineare Thunb. In addition, the biogas residue promoted Sedum lineare Thunb growth under low temperature, increased height, coverage, tillering ability and chlorophyll content. The average quality assessment scores were all higher than 6, showing that Sedum lineare Thunb grew normally basically. The best comprehensive quality of Sedum lineare Thunb was reached when the biogas residue to sandy soil ratio for the substrate was 4 ∶ 5 under medium and low temperatures.