Role of microbial communities in mediating ecosystem response to disturbance

Abstract

consideration of disturbance. Yet, a synthetic understanding of the factors that govern postdisturbance ecosystem change is lacking. The role of microbial communities in mediating post-disturbance biogeochemistry has been overlooked in favor of a focus on process rates themselves and assuming that microbes act in a ‘‘black box.’’ For example, in the recent, globally comprehensive, Millenium Ecosystem Assessment, recommendations for critical research areas and data collection to forecast changes in ecosystem services generally lack any direct reference to soil biotic communities (Agardy et al. 2005, p. 837). However, understanding alterations of microbially mediated ecosystem function is critical for understanding nutrient limitations, ecosystem productivity, and ultimately, ecosystem services. Instead, observations of altered ecosystem function after disturbance tend to be indirect and descriptive, lacking a mechanistic basis for interpreting the observed changes. This lack of mechanistic understanding of the relationship between soil microbial communities, ecosystem function and their potential responses to disturbance, limits our ability to make predictions across spatial and temporal domains. At the same time, we have gained significant insight into, and ability to detect, how microbial community activity alters ecosystem processes. Given increasing pressures on ecologists to interpret and forecast the effects of global change, ignoring these insights regarding the fundamental role of micro-organisms is not acceptable. The current challenge therefore is to synthesize knowledge about microbial community activity following disturbance to determine when, how, and why microbial community structure and function mediate ecosystem responses to disturbance. This special issue includes studies that explore the relationship between microbial communities and disturbance, and the consequence of microbiological changes on ecosystem function. Past studies demonstrating that disturbance alters microbial communities have generally been casespecific. As a result, little is known about the relative impact of different types of disturbances and their variation in time and space. In this issue, I asked authors to address microbial structure and function in response to the particular disturbance with which they were most familiar, and to synthesize the ecological lessons from these studies. Consequently, the papers cover a wide range of disturbance types including global change, atmospheric CO2 enrichment, wetland disruption, and E. A. H. Smithwick (&) Department of Zoology, Birge Hall, 430 Lincoln Drive, University of Wisconsin, Madison, WI 53706, USA e-mail: easmithwick@wisc.edu Plant Soil (2006) 289:1–3 DOI 10.1007/s11104-006-9084-5