Clonal reproduction as a double-edged sword: antagonistic and synergistic effects on the warmed population maintenance of alpine species across successional stages of plateau zokor disturbance

A central question in biodiversity conservation under global change is whether species maintain viable populations under both mammal disturbance and climate warming. This requires demographic studies that integrating vital rates responses to mammal disturbance and climate warming across an entire life to. Using Integral Projection Models parameterized with demographic data, we found the population growth rates of Thermopsis lanceolata under both ambient and warming conditions, initially decreased on new mounds, further declined on seminew mounds, but eventually exceeded initial levels on old mounds. This stage-dependent responses were largely driven by clonal reproduction (i.e., clonal production and/or ramet size distribution), which emerged as both the most sensitive vital rate and the primary contributor to variation in population growth rates across recovery stages. Additionally, we found that the combined effects of plateau zokor disturbance and warming on population growth rates of new mounds was greater than the sum of their individual effects, leading to population decline on new mounds. Such synergistical effects was mainly due to a larger decrease of ramet size distribution. These findings suggest that multifactorial experiments are important for biodiversity research, rather than merely adding single effects on population dynamics. In addition, clonal reproduction may be a key vital rate for population maintenance under global change.