坪床基质对兰引Ⅲ号结缕草根系生长及分布的影响

Effects of Five Turf-bed Substrates on the Root Growth and Distribution of Zoysia japonica 'Lanyin No.Ⅲ'

坪床结构对草坪草根系和草坪使用质量的影响很大.为探讨5种坪床基质对兰引Ⅲ号结缕草（Zoysia japonica‘Lanyin No.Ⅲ’）根系生长的影响,试验设计5种坪床基质：100％纯砂（A）,砂∶泥炭（85％∶15％）（B）,砂∶土（85％∶15％）（C）,砂∶土∶泥炭（85％∶7.5％∶7.5％）（D）,100％纯土（E）.结果表明：根长密度、根表面积密度随坪床深度的加深而减小,纯土坪床的上述根系指标显著小于砂基坪床;一级根在0～5 cm的根层中分布最多l而二级根在5～10 cm根层分布最多;3种砂质混合基质中,砂＋泥炭混合基质好于砂＋土和砂＋土＋泥炭2种混合基质.在土壤各层深度中,砂基坪床的根平均直径显著大于纯土坪床.纯砂坪床的地下生物量最大,而纯土坪床0～5 cm根层内根系生物量所占比例最大.综合分析认为,砂基坪床适合做运动场草坪,其中以砂与泥炭混合基质最好,纯土坪床则排水不良,不适宜做运动场草坪.

There is a substantial connection among turf-bed substrate, root system and usage quality of turf. Here the effects of different turf-bed substrates on the root growth of Zoysia japonica ＇Lanyin No. Ⅲ＇ were discussed with 5 treatments of turf-bed substrates including 100% pure-sand （A）, sand ： peat （85% ： 15%） （B）, sand ： soil （85% ： 15%） （C）, sand ： soil ： peat （85% ： 7.5% ： 7.5%） （D）, pure- soil （E）. The results showed that root length density, root surface area density decreased with the depth of soil layer increasing. The values of root characteristics of pure-soil substrate were significant less than that of sand-based substrates. The first order roots were mostly abundant in 0~ 5 cm layer, while the sec- ond order roots mainly distributed in the middle soil layer of 5~10 cm. Sand＋peat substrate was better than sand＋peat＋soil substrate and sand＋soil substrate. The average diameter of first order root of sand- based substrate was significantly larger than pure-soil substrate. Total dry weight of underground biomass in pure-sand substrate was the highest, whereas pure-soil substrate had the largest root biomass in 0 ~ 5 cm soil layer. Comprehensive analysis indicated that sand-based bed was suitable for sports turf and sand： peat substrate was the best one. The pure-soil substrate was considered to be unsuitable for sports turf due to its poor drainage.