Grman Emily, Zirbel Chad R, Bassett Tyler, Brudvig Lars A
Department of Biology, Eastern Michigan University, 441 Mark Jefferson Science Complex, Ypsilanti, MI, 48197, USA.
Department of Plant Biology, Michigan State University, East Lansing, MI, USA.
Oecologia. 2018 Nov;188(3):837-848. doi: 10.1007/s00442-018-4248-6. Epub 2018 Aug 17.
The loss of biodiversity at local and larger scales has potentially dramatic effects on ecosystem functioning. Many studies have shown that ecosystem functioning depends on biodiversity, but the role of beta diversity, spatial variation in community composition, is less clear than that of local-scale (alpha) diversity. To test the hypothesis that beta diversity would increase ecosystem multifunctionality through variation in species functional traits, we gathered data on plant community composition, plant functional traits, and seven ecosystem functions across 29 restored prairies. We found that averaged multifunctionality (mean of seven ecosystem functions) increased with both taxonomic beta diversity and functional beta diversity. The abundance of the dominant species, big bluestem, played a more minor role, suggesting a limited role for the selection effect. Neither taxonomic nor functional alpha richness was associated with multifunctionality, though this finding may be sensitive to the identity of the functions included because alpha diversity was associated with some individual functions in opposing directions. These findings suggest that in systems structured largely by natural processes, beta diversity (a patchwork of functionally different plant communities) and dominant species abundance may be more important than alpha diversity in fostering ecosystem multifunctionality. These findings suggest the need for an increased focus on community heterogeneity to reestablish functional ecosystems during restoration.
在局部及更大尺度上生物多样性的丧失可能会对生态系统功能产生巨大影响。许多研究表明，生态系统功能依赖于生物多样性，但相较于局部尺度（α）多样性，群落组成的空间变异即β多样性的作用尚不清楚。为了验证β多样性会通过物种功能性状的变异提高生态系统多功能性这一假设，我们收集了29个恢复草原的植物群落组成、植物功能性状以及七种生态系统功能的数据。我们发现，平均多功能性（七种生态系统功能的平均值）随着分类学β多样性和功能β多样性的增加而增加。优势物种大须芒草的丰度所起的作用较小，这表明选择效应的作用有限。分类学α丰富度和功能α丰富度均与多功能性无关，不过这一发现可能对所纳入功能的特性敏感，因为α多样性与某些个体功能呈相反方向相关。这些发现表明，在主要由自然过程构建的系统中，β多样性（功能不同的植物群落拼凑而成）和优势物种丰度在促进生态系统多功能性方面可能比α多样性更为重要。这些发现表明，在恢复过程中重建功能生态系统时，需要更多地关注群落异质性。
