Abstract In the Great Basin, changes in climate and associated fire regimes may alter the density and distribution of shrubs, changing the structure and diet quality of plants in burned areas. We evaluated how the structural and phytochemical characteristics of three-tip sagebrush (Artemisia tripartita) relative to Wyoming big sagebrush (A. tridentata wyomingensis) influence the winter foraging ecology of Greater Sage-Grouse (Centrocercus urophasianus) at a site with a known history of fire in south-central Idaho. Three-tip sagebrush had lower protein content and lower chemical defenses compared to Wyoming big sagebrush. We found that time since last fire over a 30-year history was more strongly correlated with changes in phytochemicals in three-tip sagebrush compared to Wyoming big sagebrush. Despite phytochemical differences, both Wyoming big sagebrush and three-tip sagebrush were browsed relative to their availability. However, within a species, smaller plant height and lower concentrations of phytochemicals, specifically two individual monoterpenes, explained diet selection by sage-grouse. Our results indicate that dietary quality of three-tip sagebrush may provide acceptable forage for sage-grouse in post-fire landscapes where other species of sagebrush have not yet recovered. However, relying on re-establishment of one species of sagebrush without consideration of structural and dietary quality may compromise successful conservation efforts.

中文翻译：

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火灾后大松鸡冬季觅食生态

摘要 在大盆地，气候和相关火灾状况的变化可能会改变灌木的密度和分布，从而改变燃烧地区植物的结构和饮食质量。我们评估了三尖山艾树 (Artemisia tripartita) 相对于怀俄明州大山艾树 (A. tridentata wyomingensis) 的结构和植物化学特征如何影响大鼠尾草 (Centrocercus urophasianus) 在已知历史的地点的冬季觅食生态爱达荷州中南部发生火灾。与怀俄明州大山艾树相比，三尖山艾树具有较低的蛋白质含量和较低的化学防御。我们发现，与怀俄明州大山艾树相比，自上次火灾以来 30 年的历史时间与三尖山艾树中植物化学物质的变化更密切相关。尽管植物化学差异，怀俄明州大山艾树和三尖山艾树都根据其可用性进行了浏览。然而，在一个物种内，较小的植物高度和较低浓度的植物化学物质，特别是两种单独的单萜，解释了鼠尾草的饮食选择。我们的结果表明，三尖山艾树的膳食质量可能为其他山艾树物种尚未恢复的火灾后景观中的鼠尾草提供可接受的草料。然而，在不考虑结构和膳食质量的情况下依靠重新建立一种山艾树可能会影响成功的保护工作。由鼠尾草解释饮食选择。我们的结果表明，三尖山艾树的膳食质量可能为其他山艾树物种尚未恢复的火灾后景观中的鼠尾草提供可接受的草料。然而，在不考虑结构和膳食质量的情况下依靠重新建立一种山艾树可能会影响成功的保护工作。由鼠尾草解释饮食选择。我们的结果表明，三尖山艾树的膳食质量可能为其他山艾树物种尚未恢复的火灾后景观中的鼠尾草提供可接受的草料。然而，在不考虑结构和膳食质量的情况下依靠重新建立一种山艾树可能会影响成功的保护工作。