Dryland ecosystems generally require active restoration to recover from severe land degradation caused by resource and energy extraction operations. While seeding remains one of the most used forms of active restoration, land managers in dryland systems have generally had difficulty re-establishing desirable plant communities, due in part to alterations in supporting ecosystem processes and the episodic nature of resource availability. In this study, we examined the impacts of site preparation, seeding, and livestock grazing on developing plant communities after the construction of a buried natural gas pipeline corridor in the southwestern United States. We monitored plant species cover and composition beginning with the second season of growth through the sixth. Analysis of each individual year show that conclusions from the initial year of data collection did not well represent the findings in the following years. The site preparation and topsoil treatment had an ongoing positive effect on richness and cover compared to the nearby baseline conditions, while seeding only further increased cover and richness in the first year of monitoring (second season of growth). However, without seeding, the plant communities were driven by ruderal, annual species, whereas the seeded plant communities were driven by desirable seeded perennial grasses and forbs. Grazing and trampling effects were not significant overall, and the effects of livestock may have been confounded with effects of small mammals due to the exclosure configuration. We suggest that the site preparation, topsoil treatment, and configuration linearity of the disturbance corridor allowed for high levels of natural recruitment.

中文翻译：

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整地的效果与在旱地恢复点播种的效果相同：6 年的植物群落发展

旱地生态系统通常需要积极恢复，以从资源和能源开采作业造成的严重土地退化中恢复过来。虽然播种仍然是最常用的主动恢复形式之一，但旱地系统的土地管理者通常难以重建理想的植物群落，部分原因是支持生态系统过程的改变和资源可用性的偶然性。在这项研究中，我们研究了在美国西南部建造埋地天然气管道走廊后，整地、播种和放牧对发展中的植物群落的影响。我们从第二个生长季节到第六个季节开始监测植物物种的覆盖率和组成。对每一年的分析表明，从最初一年收集数据得出的结论并不能很好地代表随后几年的调查结果。与附近的基线条件相比，整地和表土处理对丰富度和覆盖度具有持续的积极影响，而播种只会在监测的第一年（第二个生长季节）进一步增加覆盖度和丰富度。然而，在没有播种的情况下，植物群落由粗壮的一年生物种驱动，而种子植物群落由理想的多年生禾本科植物和杂草驱动。总体而言，放牧和践踏的影响并不显着，而且由于围栏配置，牲畜的影响可能与小型哺乳动物的影响相混淆。我们建议整地、表土处理、