Ohlert Timothy J, Hallmark Alesia, Rudgers Jennifer A, Peters Debra P C, Collins Scott L
Department of Biology, University of New Mexico, Albuquerque, New Mexico, USA.
Department of Biology, Colorado State University, Fort Collins, Colorado, USA.
Ecology. 2025 Aug;106(8):1-10. doi: 10.1002/ecy.70164.
Dominant species play a key role in plant communities, influencing the abundance and richness of subordinate species through competitive and facilitative interactions. However, generalizations about the effects of dominant plant species in grasslands can be difficult due to the many differences among communities, such as abiotic conditions and regional species pools. To overcome this issue, we conducted a dominant species removal experiment in two semiarid grassland communities at the Sevilleta National Wildlife Refuge in central New Mexico. These communities had different dominant species but similar abiotic conditions and regional species pools. We studied the effects of removing dominant species on community composition, diversity, and aboveground net primary production (ANPP) over a 23-year period. Our results showed that dominant grasses suppressed both richness and abundance of subordinate species. In the Chihuahuan Desert grassland, the loss of Bouteloua eriopoda was only partially compensated for by subordinate species, while in the Great Plains grassland, the loss of Bouteloua gracilis was fully compensated for after 16 years. Despite increased species richness, removing dominant species reduced ANPP and resulted in a negative relationship between species richness and ANPP in both grasslands. These results have important implications for ecosystem management and conservation, highlighting the potential impact of losing dominant species on subordinate species and community dynamics.
优势物种在植物群落中起着关键作用，通过竞争和促进作用影响从属物种的丰度和丰富度。然而，由于不同群落之间存在许多差异，如非生物条件和区域物种库，因此很难对草原上优势植物物种的影响进行概括。为了克服这个问题，我们在新墨西哥州中部塞维列塔国家野生动物保护区的两个半干旱草原群落中进行了优势物种去除实验。这些群落具有不同的优势物种，但非生物条件和区域物种库相似。我们研究了在23年的时间里去除优势物种对群落组成、多样性和地上净初级生产力（ANPP）的影响。我们的结果表明，优势草本植物抑制了从属物种的丰富度和丰度。在奇瓦瓦沙漠草原，布氏草的消失仅得到了从属物种的部分补偿，而在大平原草原，纤细布氏草消失16年后得到了完全补偿。尽管物种丰富度增加，但去除优势物种降低了ANPP，并导致两个草原的物种丰富度与ANPP之间呈负相关。这些结果对生态系统管理和保护具有重要意义，突出了失去优势物种对从属物种和群落动态的潜在影响。
