Aridity structures the microbial potential for carbon cycling and mediates the impact of mammal bioturbation at the continental scale

In Australia, the historical loss of native digging mammals has profoundly changed ecosystems and their functioning. However, little is known about how the decline in digging mammal presence alters microbes and their functional potential, and how these relationships are affected by aridity. Using a metagenomics approach we surveyed the soil metagenomes from five reserves with reintroduced digging mammals and adjacent un-manipulated areas over an aridity gradient ranging from 0.077 to 0.88 (1-aridity index; 166 to 900 mm average annual rainfall), with site ranging over 3300 km of the Australian continent.

在澳大利亚，本土掘土哺乳动物的历史性丧失已深刻改变了生态系统及其功能运转。然而，目前学界对掘土哺乳动物种群数量下降如何改变土壤微生物及其功能潜力，以及干旱度如何影响这类关联仍知之甚少。本研究采用宏基因组学（metagenomics）方法，对分布于澳大利亚大陆3300公里跨度范围内的样点进行了调研，这些样点的干旱度梯度介于0.077至0.88之间（即1减去干旱度指数；对应年平均降雨量166至900毫米），涵盖了5个已重新引入掘土哺乳动物的保护区及其邻近未受人为干预区域的土壤宏基因组。