Department of Community Ecology, UFZ- Helmholtz Centre for Environmental Research, Theodor-Lieser-Str. 4, 06120, Halle, Germany.
Glob Chang Biol. 2013 Mar;19(3):892-9. doi: 10.1111/gcb.12087. Epub 2012 Dec 10.
There is increasing evidence that species can evolve rapidly in response to environmental change. However, although land use is one of the key drivers of current environmental change, studies of its evolutionary consequences are still fairly scarce, in particular studies that examine land-use effects across large numbers of populations, and discriminate between different aspects of land use. Here, we investigated genetic differentiation in relation to land use in the annual grass Bromus hordeaceus. A common garden study with offspring from 51 populations from three regions and a broad range of land-use types and intensities showed that there was indeed systematic population differentiation of ecologically important plant traits in relation to land use, in particular due to increasing mowing and grazing intensities. We also found strong land-use-related genetic differentiation in plant phenology, where the onset of flowering consistently shifted away from the typical time of management. In addition, increased grazing intensity significantly increased the genetic variability within populations. Our study suggests that land use can cause considerable genetic differentiation among plant populations, and that the timing of land use may select for phenological escape strategies, particularly in monocarpic plant species.
越来越多的证据表明，物种可以迅速进化以适应环境变化。然而，尽管土地利用是当前环境变化的主要驱动因素之一，但对其进化后果的研究仍然相当稀少，特别是研究大规模种群的土地利用效应，并区分土地利用的不同方面。在这里，我们研究了一年生草本植物雀麦（Bromus hordeaceus）与土地利用有关的遗传分化。对来自三个地区、广泛的土地利用类型和强度的 51 个种群的后代进行的一项田间试验表明，与土地利用有关的生态重要植物性状确实存在系统的种群分化，特别是由于割草和放牧强度的增加。我们还发现植物物候与土地利用之间存在强烈的相关性遗传分化，其中开花时间始终偏离管理的典型时间。此外，增加放牧强度显著增加了种群内的遗传变异性。我们的研究表明，土地利用可以导致植物种群之间产生相当大的遗传分化，而且土地利用的时间可能会选择出物候逃避策略，特别是在单年生植物物种中。
