Soil bacterial communities vary more by season than with over two decades of experimental warming in Arctic tussock tundra
Soil bacterial communities vary more by season than with over two decades of experimental warming in Arctic tussock tundra
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DOI：
10.1525/elementa.2021.00116
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发表时间：
2021-01
期刊：
影响因子：
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通讯作者：
G. Pold;J. Schimel;S. Sistla
中科院分区：
文献类型：
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作者：
G. Pold;J. Schimel;S. Sistla
高纬度生态系统的特点是土壤寒冷，冬季长，其大部分生物地球化学直接或间接受温度控制。气候变暖导致了草袜冻土带上灌木植物群落的扩张，但这些明显的地上变化是否与地下微生物群落的变化相对应还不太确定。使用溴脱氧尿苷标记生长细胞，我们评估了总细菌群落和活跃生长的细菌群落在一年中以及在22年被动的夏季变暖之后是如何变化的。我们发现，细菌群落结构的变化与土壤因子和采样时间点有关，但不受气候变暖的影响。随着气候变暖，地上植物群落变得以灌木为主，因此我们的结果表明，地下细菌群落并没有跟踪地上植物群落的变化。因此，使用空间换时间方法预测灌木覆盖率增加如何改变细菌群落的研究，可能不能代表随着北极继续变暖，植物群落的原位变化将如何影响微生物群落。
High latitude ecosystems are characterized by cold soils and long winters, with much of their biogeochemistry directly or indirectly controlled by temperature. Climate warming has led to an expansion of shrubby plant communities across tussock tundra, but whether these clear aboveground shifts correspond to changes in the microbial community belowground remains less certain. Using bromodeoxyuridine to label growing cells, we evaluated how total and actively growing bacterial communities varied throughout a year and following 22 years of passive summer warming. We found that changes in total and actively growing bacterial community structures were correlated with edaphic factors and time point sampled, but were unaffected by warming. The aboveground plant community had become more shrub-dominated with warming at this site, and so our results indicate that belowground bacterial communities did not track changes in the aboveground plant community. As such, studies that have used space-for-time methods to predict how increased shrub cover has altered bacterial communities may not be representative of how the microbial community will be affected by in situ changes in the plant community as the Arctic continues to warm.