Roadside vegetation provides a multitude of ecosystem services including pollutant remediation, runoff reduction, wildlife habitat, and aesthetic scenery. Establishment of permanent vegetation along paved roads after construction can be challenging, particularly within 1 m of the pavement. Adverse soil conditions could be one of the leading factors limiting roadside vegetation growth. In this study, we assessed soil physical and chemical properties along a transect perpendicular to the road at six micro-topographic positions (road edge, shoulder, side slope, ditch, backslope, and field edge) along two highway segments near Beaver Crossing and Sargent, NE, USA. At the Beaver Crossing site, Na concentration was 81 times, exchangeable Na 66 times, and cone index (compaction parameter) 6 times higher at the road edge position (closest to the paved road and with sparse vegetation) compared to positions with abundant vegetation (ditch or field edge). At the Sargent site, Na concentration was 111 times, exchangeable Na 213 times, and cone index up to 2 times higher at the road edge compared to ditch or field edge positions. Likewise, electrical conductivity (EC) was higher while macroaggregation and water infiltration were lower at the road edge than ditch or field edge positions. Soil properties improved with increasing distance from the road. Exchangeable Na percentage and cone index at the road edge exceeded threshold levels for growth of sensitive plants. Thus, high Na concentration and increased compaction at the road edge appear to be the leading soil properties limiting vegetation establishment along Nebraska highways. This article is protected by copyright. All rights reserved.

中文翻译：

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限制路边植被建立的土壤特性

路边植被提供了多种生态系统服务，包括污染物修复、径流减少、野生动物栖息地和美学景观。施工后沿铺砌道路建立永久性植被可能具有挑战性，尤其是在距人行道 1 m 范围内。不利的土壤条件可能是限制路边植被生长的主要因素之一。在这项研究中，我们评估了沿 Beaver Crossing 和 Sargent 附近两个高速公路路段的六个微地形位置（道路边缘、路肩、边坡、沟渠、后坡和田野边缘）垂直于道路的断面的土壤物理和化学性质, NE, 美国。在 Beaver Crossing 站点，Na 浓度为 81 倍，可交换 Na 66 倍，与植被丰富的位置（沟渠或田地边缘）相比，道路边缘位置（最靠近铺装道路且植被稀疏）的锥体指数（压实参数）高 6 倍。在萨金特站点，与沟渠或田地边缘位置相比，道路边缘的 Na 浓度是 111 倍，可交换 Na 是 213 倍，锥指数高达 2 倍。同样，与沟渠或田地边缘位置相比，道路边缘的电导率 (EC) 更高，而大团聚和水渗透更低。土壤特性随着与道路距离的增加而改善。道路边缘的可交换钠百分比和锥体指数超过敏感植物生长的阈值水平。因此，道路边缘的高钠浓度和增加的压实似乎是限制内布拉斯加州高速公路沿线植被建立的主要土壤特性。本文受版权保护。版权所有。