More than 100 tidal marsh creation projects were constructed throughout the Fraser River Estuary, British Columbia, Canada from the 1980s to present. Past studies described and evaluated many of these projects and found varied success, but the underlying factors that determine project outcomes remain uncertain. Combining field sampling, spatial analysis, and statistical modeling of plant communities, we aim to address this knowledge gap by asking what factors influence the resilience of created marshes, as measured by (1) persistence of marsh vegetation, (2) native species dominance, and (3) species richness. We observed marsh recession in 40 of the 78 projects visited, representing 23,666 m² (9.3%) of the 254,357 m² of created marsh surveyed. Increases in mean site elevation had a negative effect on percent recessed area, while sites in the north branch of the river and sites further upriver were more prone to recession. From field observations and data interpretation we suggest that wake erosion and Canada Goose (Branta canadensis) herbivory may be drivers behind these losses and warrant further investigation. Dominance of native species declined with distance upriver, though invasive cattail (Typha angustifolia, T. × glauca) defied this trend, dominating outer estuary sites, particularly closed embayments, when present. Native and non-native richness shared similar patterns and were comparable between reference and created marshes, increasing on average with elevation and distance upriver. These findings offer insight into how site design and location influence the outcome of marsh creation projects, and the challenges presented by stressors and environmental change in estuaries.

从 20 世纪 80 年代至今，加拿大不列颠哥伦比亚省弗雷泽河口建造了 100 多个潮汐沼泽创造项目。过去的研究描述和评估了许多此类项目，并发现了不同的成功，但决定项目结果的根本因素仍然不确定。结合实地采样、空间分析和植物群落的统计模型，我们的目标是通过询问哪些因素影响所创造的沼泽的恢复力来解决这一知识差距，衡量标准是（1）沼泽植被的持久性，（2）本地物种优势， (3)物种丰富度。我们在访问的 78 个项目中观察到 40 个项目出现沼泽衰退，占所调查的 254,357 m ^{2沼泽面积中的 23,666 m 2} (9.3%) 。平均场地海拔的增加对凹陷面积百分比产生负面影响，而河流北支流和上游更远的地点更容易出现衰退。根据现场观察和数据解释，我们认为尾流侵蚀和加拿大鹅 ( Branta canadensis ) 食草可能是这些损失背后的驱动因素，值得进一步调查。本地物种的优势随着上游距离的增加而下降，尽管入侵香蒲（Typha angustifolia，T.  ×  glauca）违背了这一趋势，主导了外河口地点，特别是封闭的海湾（如果存在）。本地和非本地丰富度具有相似的模式，并且参考沼泽和人工沼泽之间具有可比性，平均随着海拔和上游距离的增加而增加。这些发现让我们深入了解场地设计和位置如何影响沼泽创建项目的结果，以及河口压力源和环境变化带来的挑战。