Abstract Highway roadside landscapes can be used to increase urban canopy cover by way of tree planting and successful tree establishment. Soil compaction and topsoil removal resulting from construction activities along roadside sites, contributes toward extensive and prolonged transplant stress; limiting the survival and effective establishment of planted trees. The current study sought to evaluate the efficacy of soil restoration as an intervention tool for facilitating the long term success of tree plantings on two unmaintained highway roadside sites. Soil level impacts immediately following and 5 years post restoration were therefore characterized. Restoration methods included mechanical de-compaction with and without the addition of increasing rates of organic amendment (0 %, 10 %, 25 % and 50 % v/v municipal food and yard waste) to improve the key soil properties (Db and SOM) influencing tree survival and establishment. At 5 years post restoration, total survivorship ranged from 46 to 92 % according to treatment, while the greatest cumulative tree growth as demonstrated by the cumulative change in tree height and trunk diameter was found to occur across trees planted into the 25 % v/v treatments. Average Db and SOM for the 25 % v/v treatments, although not the most improved of all treatments, was consistently and significantly improved as compared to compacted, amended and de-compacted, un-amended controls over the course of the trial. The results of the current study demonstrate the inadequacy of survivorship as a sole measure of planting success. Findings pertaining to individual tree and soil level impacts support the incorporation of moderate volumes of stabilized, high quality organic amendment prior to planting as an effective method for providing immediate and sustained improvements to Db and SOM. These improvements are found to coincide with improved tree establishment as demonstrated by cumulative tree growth, across the otherwise unfavourable soil conditions that are characteristic of post-construction, naturalization planting sites.

中文翻译：

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堆肥改善了公路路边的土壤特性和树木生长

摘要 公路路旁景观可通过植树造林，增加城市冠层覆盖。路边施工活动造成的土壤压实和表土清除，导致广泛和长期的移植压力；限制种植树木的存活和有效建立。目前的研究试图评估土壤恢复作为促进在两个未维护的公路路边场地植树长期成功的干预工具的功效。因此，对紧随恢复和恢复后 5 年的土壤水平影响进行了表征。修复方法包括机械去压实，添加和不添加有机添加物（0 %、10 %、25 % 和 50 % v/v 城市食品和庭院垃圾）以改善影响树木存活和建立的关键土壤特性（Db 和 SOM）。在恢复后 5 年，根据处理的不同，总存活率为 46% 到 92%，而通过树高和树干直径的累积变化证明的最大累积树木生长发生在种植到 25% v/v 的树木中治疗。25% v/v 处理的平均 Db 和 SOM，虽然不是所有处理中改善最多的，但在试验过程中与压实、修正和去压实、未修正的对照相比，持续且显着改善。当前研究的结果表明，将存活率作为种植成功的唯一衡量标准是不够的。与个别树木和土壤水平影响有关的结果支持在种植前加入适量稳定的高质量有机改良剂，作为立即和持续改善 Db 和 SOM 的有效方法。发现这些改进与树木生长的改善相一致，如累积的树木生长所证明的那样，跨越其他不利的土壤条件，这些条件是建设后归化种植地点的特征。