@article{KurzeBareitherMetz2017,
  author    = {Kurze, Susanne and Bareither, Nils and Metz, Johannes},
  title     = {Phenology, roots and reproductive allocation, but not the LHS scheme, shape ecotypes along an aridity gradient},
  series = {Perspectives in plant ecology, evolution and systematics},
  volume    = {29},
  journal   = {Perspectives in plant ecology, evolution and systematics},
  publisher = {Elsevier},
  address   = {Jena},
  issn      = {1433-8319},
  doi       = {10.1016/j.ppees.2017.09.004},
  pages     = {20 -- 29},
  year      = {2017},
  abstract  = {This study tested systematically at two spatial scales for key traits shaping within-species ecotypic differentiation under increasing aridity. It assessed different plant strategy theories and considered potential implications for climate change. We studied the widespread Mediterranean grass Brachypodium hybridum. At large scale, we tested 14 populations along a steep natural aridity gradient (114-954 mm annual rainfall). At small scale, we tested the microclimatic contrast between plants originating from corresponding north (more mesic) and south (more arid) exposed hillslopes. Fifteen traits were measured in the greenhouse, including the popular traits of the LeafHeight- Seed scheme (SLA, plant height, seed mass), several traits on phenology, architecture, growth, fitness, and rarely measured root traits. Clear trait shifts indicated ecotypic differentiation along the large-scale gradient. Earlier phenology, higher reproductive allocation and reduced root investment characterized arid ecotypes. Surprisingly, no trait of the Leaf-Height-Seed scheme shifted with aridity and root responses were opposite to the theory of optimal resource partitioning. Trait differences between north and south exposures were small, often inconsistent between sites, and poorly matched the trends across the large-scale gradient. South exposures thus appeared unlikely to harbour distinct ecotypes better adapted to aridity. Our findings highlight ecotypes as a crucial way how species span environmental gradients, yet underpinning their restriction at small spatial scales. In combination, this possibly renders populations more vulnerable to climate change. We draw attention to specific, partly unexpected traits and pose the question whether the LeafHeight- Seed scheme has limited applicability for intraspecific investigations in drylands.},
  language  = {en}
}
@article{MayGiladiRistowetal.2013,
  author    = {May, Felix and Giladi, Itamar and Ristow, Michael and Ziv, Yaron and Jeltsch, Florian},
  title     = {Plant functional traits and community assembly along interacting gradients of productivity and fragmentation},
  series = {Perspectives in plant ecology, evolution and systematics},
  volume    = {15},
  journal   = {Perspectives in plant ecology, evolution and systematics},
  number    = {6},
  publisher = {Elsevier},
  address   = {Jena},
  issn      = {1433-8319},
  doi       = {10.1016/j.ppees.2013.08.002},
  pages     = {304 -- 318},
  year      = {2013},
  abstract  = {Quantifying the association of plant functional traits to environmental gradients is a promising approach for understanding and projecting community responses to land use and climatic changes. Although habitat fragmentation and climate are expected to affect plant communities interactively, there is a lack of empirical studies addressing trait associations to fragmentation in different climatic regimes. In this study, we analyse data on the key functional traits: specific leaf area (SLA), plant height, seed mass and seed number. First, we assess the evidence for the community assembly mechanisms habitat filtering and competition at different spatial scales, using several null-models and a comprehensive set of community-level trait convergence and divergence indices. Second, we analyse the association of community-mean traits with patch area and connectivity along a south-north productivity gradient. We found clear evidence for trait convergence due to habitat filtering. In contrast, the evidence for trait divergence due to competition fundamentally depended on the null-model used. When the null-model controlled for habitat filtering, there was only evidence for trait divergence at the smallest sampling scale (0.25 m x 0.25 m). All traits varied significantly along the S-N productivity gradient. While plant height and SLA were consistently associated with fragmentation, the association of seed mass and seed number with fragmentation changed along the S-N gradient. Our findings indicate trait convergence due to drought stress in the arid sites and due to higher productivity in the mesic sites. The association of plant traits to fragmentation is likely driven by increased colonization ability in small and/or isolated patches (plant height, seed number) or increased persistence ability in isolated patches (seed mass). Our study provides the first empirical test of trait associations with fragmentation along a productivity gradient. We conclude that it is crucial to study the interactive effects of different ecological drivers on plant functional traits.},
  language  = {en}
}