Decline of dry grassland specialists in Mediterranean high-mountain communities influenced by recent climate warming
Decline of dry grassland specialists in Mediterranean high-mountain communities influenced by recent climate warming
复制标题
受近期气候变暖影响，地中海高山社区干旱草原专家的减少
DOI：
10.1111/jvs.12198
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发表时间：
2014
影响因子：
2.8
通讯作者：
F. Fernández‐González
中科院分区：
文献类型：
--
作者：
B. Jiménez‐Alfaro;R. Gavilán;A. Escudero;J. Iriondo;F. Fernández‐González
地中海发生了什么变化
在过去的50年里，高山社区？做这些
变化反映了干旱草原的上升和下降
由于气候变暖，？位置上带
（海拔1900- 2400米）在西班牙的瓜达拉马山脉MethodsWe
重新调查了50个山顶的干旱草原群落，
上世纪60年代到80年代的样本新的情节是
在相同的地点和相同的条件下，
原始调查。对物种水平的变化进行了评价
通过比较，在两个调查期间，物种
频率和最佳高度估计当地
用Maxent做的分销模型。社区的变化
通过比较物种丰富度和
两次调查的组成与海拔、地块
调查之间的大小和时间。我们评估了观察到的
整个数据集和物种组，
物种进入干旱草原专家，其他高山物种
而多面手出现在更宽的海拔范围内。
结果干眼症发生率普遍下降，
草原专家，增加通才的频率
其他物种也没有明显的趋势。向上的转变是
主要在通才中发现，
频率.在社区一级，我们发现
物种丰富度的增加主要取决于
在多面手;加上干燥的数量下降，
草原专家社区的结构
历史调查和
再调查，这主要是与人数有关，
年和越来越多的通才的主导地位。
结论与其他研究中观察到的趋势相反，
地中海高山社区，我们的研究报告，
物种丰富度的普遍增加，尽管这种影响是
与此同时，干旱草原专家减少。的
观察到的趋势支持正在进行的地方物种替换
低海拔物种，以及相关的群落变化
集会尽管重访研究的局限性
为了评估气候驱动的变化，我们的结果强调了
有必要开展更多的研究，以评估
地中海高山社区的干旱。
QuestionsWhat changes have occurred in Mediterranean
high-mountain communities during the last 50yr? Do these
changes reflect upward shifts and decline in dry grassland
specialists due to climate warming? LocationUpper belt
(1900-2400m a.s.l.) in Sierra de Guadarrama, Spain. MethodsWe
re-surveyed dry grassland communities in 50 summits that were
previously sampled between the 1960s and 1980s. New plots were
placed in the same localities and the same conditions as the
original surveys. Changes at the species level were evaluated
by comparing, between the two survey periods, species
frequencies and optimal altitude estimated by local
distribution models done with Maxent. Changes at the community
level were assessed by comparing species richness and
composition of the two surveys in relation to altitude, plot
size and time between surveys. We evaluated observed changes in
the whole data set and species groups by structuring the
species into dry grassland specialists, other alpine species
and generalists occurring at wider altitudinal ranges.
ResultsThere was a general decline in the frequency of dry
grassland specialists, an increase in frequency of generalists
and no clear trends in the other species. Upward shifts were
mainly detected in generalists, with significant increases in
frequency. At the community level, we found a general increase
in species richness that was mainly determined by the increase
in generalists; coupled with a decline in number of dry
grassland specialists. The structure of the communities
evidenced changes between the historical surveys and the
re-survey, which were mainly correlated with the number of
years and the increasing dominance of generalists.
ConclusionsIn contrast with trends observed in other
Mediterranean high-mountain communities, our study reports a
general increase in species richness, although this effect is
concurrent with a decline in dry grassland specialists. The
observed trends support on-going replacement of endemic species
by low-altitude species, and associated changes in community
assemblages. Despite the limitations of re-visitation studies
for assessing climate-driven changes, our results highlight the
necessity of developing more studies for assessing the effects
of drought in Mediterranean high-mountain communities.