Thu, Aug 05, 2021:On Demand
Background/Question/Methods
The Interior Pacific is well known for its vast forests, which have been studied with respect to their community composition and ecological functioning. However, few ecologists know that the region is also home to meadows that occur scattered among its mid-elevational forests and prevail on shallow and vernally seepy soils. Referred to as “Bedrock Meadows” by a regional botanist, this habitat type has never been studied, and its species composition and diversity remain unknown. However, given their small size and open structure, Bedrock Meadows could be disproportionately vulnerable to the effects of human disturbance and non-native species invasions. In order to evaluate their importance for conservation and land-use planning, it is crucial to understand how Bedrock Meadows differ from other open habitat types in the region.
We compared Bedrock Meadows to four other habitat types in the wider region, incl. prairie and intermountain grasslands, maritime mountain meadows, alpine and timberline meadows, and asked how they differ with respect to: (i) species composition of vascular plants, (ii) climate characteristics, (iii) and functional composition (plant-life spans, growth forms).
We combined field data with existing data (total n = 1162 plots, incl. 110 plots in Bedrock Meadows) and compared habitat types using classification and indirect ordination techniques. Our results show that Bedrock Meadows form communities that are distinct with respect to their taxonomic and functional composition, and climate attributes.
Results/Conclusions Their climate attributes take an intermediate position between coastal and interior open habitats, and between high and low altitudinal climate conditions. Compared to the other open habitat types, Bedrock Meadows have high proportions of plants surviving harsh conditions during unfavorable conditions as seeds or with subterranean storage organs, here mostly bulbs and corms. Their functional composition resembles most closely those found in maritime mountain or Timberline Meadows. Given their distinct ecological attributes, bedrock meadows should be recognized as a separate habitat type. Future research needs to focus on the conservation value and threats to this habitat type and continue to explore its biological components.
Results/Conclusions Their climate attributes take an intermediate position between coastal and interior open habitats, and between high and low altitudinal climate conditions. Compared to the other open habitat types, Bedrock Meadows have high proportions of plants surviving harsh conditions during unfavorable conditions as seeds or with subterranean storage organs, here mostly bulbs and corms. Their functional composition resembles most closely those found in maritime mountain or Timberline Meadows. Given their distinct ecological attributes, bedrock meadows should be recognized as a separate habitat type. Future research needs to focus on the conservation value and threats to this habitat type and continue to explore its biological components.