Abstract:

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 ‘LanyinNo. 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 second 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.

Key words: Turf-bed substrate, Root distribution, Sport turf, Zoysia japonica ‘LanyinNo. Ⅲ’

摘要：

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 ‘LanyinNo. 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。

关键词: 坪床基质, 根系分布, 运动场草坪, 兰引Ⅲ号结缕草