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Most ecosystems are now sufficiently altered in structure and function to qualify as novel systems, and this recognition should be the starting point for ecosystem management efforts. Under the emerging biogeochemical configurations, management activities are experiments, blurring the line between basic and applied research. Responses to specific management manipulations are context specific, influenced by the current status or structure of the system, and this necessitates reference areas for management or restoration activities. Attempts to return systems to within their historical range of biotic and abiotic characteristics and processes may not be possible, and management activities directed at removing undesirable features of novel ecosystems may perpetuate or create such ecosystems. Management actions should attempt to maintain genetic and species diversity and encourage the biogeochemical characteristics that favor desirable species. Few resources currently exist to support the addition of proactive measures and rigorous experimental designs to current management activities. The necessary changes will not occur without strong input from stakeholders and policy makers, so rapid information transfer and proactive research–management activities by the scientific community are needed.

As the rate and extent of environmental change increases, traditional perspectives on ecosystem management and restoration are being juxtaposed with approaches that focus on the altered settings now being encountered or anticipated. We suggest that a combination of traditional and emerging frameworks is necessary to achieve the multiple goals of ecosystem management, including biodiversity conservation and provision of other ecosystem services such as food and fiber production, recreation, and spiritual enrichment.An effective approach entails a move away from partitioning the environment into dichotomous categories (eg natural/unnatural, production/conservation, intact/degraded). Instead, landscapes are increasingly characterized by a complex mosaic of ecosystems or "patches" in varying states of modification, each of which delivers various combinations of services and presents assorted management challenges and opportunities. These patches interact and affect broader-scale processes (such as water flows and animal migrations), necessitating the urgent development of a conservation and restoration strategy that recognizes these rapid spatial changes.Here, we focus on an emerging framework that differentiates patches according to the degree of change from a historical state (resulting from altered abiotic factors and biotic compositions), the likely extent to which such changes are reversible, and the effect of altered patches on other patches within the landscape (WebPanel 1). This framework, derived from recent research on novel ecosystems (Hobbs et al. 2009, helps to identify the relative values of ecosystems in different conditions and the management options available in each case. As seen from a landscape perspective, this framework provides a comprehensive approach to decision making and management, including much-needed prioritization of resource allocations.n Managing the whole landscape Recent analyses have highlighted the need for management and restoration efforts to go beyond site-focused interventions and to consider landscape and regional scales (Mentz et al. 2013). Ecosystem managers increas- REVIEWS REVIEWS REVIEWSManaging the whole landscape: historical, hybrid, and novel ecosystems The reality confronting ecosystem managers today is one of heterogeneous, rapidly transforming landscapes, particularly in the areas more affected by urban and agricultural development. A landscape management framework that incorporates all systems, across the spectrum of degrees of alteration, provides a fuller set of options for how and when to intervene, uses limited resources more effectively, and increases the chances of achieving management goals. That many ecosystems have departed so substantially from their historical trajectory that they defy conventional restoration is not in dispute. Acknowledging novel ecosystems need not constitute a threat to existing policy and management approaches. Rather, the development of an integrated approach to management interventions can provide options that are in tune with ...

Interactions at the aboveground-belowground interface provide important feedbacks that regulate ecosystem processes. Organisms within soil food webs are involved in processes of decomposition and nutrient mineralization, and their abundance and activity have been linked to plant ecophysiological traits such as species identity and the quality and quantity of plant tissue. We tested aboveground-belowground diversity relationships in a naturally developed plant community of native tallgrass prairie by taking soil samples from beneath naturally established grass tillers of chosen characteristics (e.g., homogeneous vs. heterogeneous plant combinations or C 4 vs. C 3 photosynthetic pathway) without imposing any disturbances to existing plant-soil relationships. The goal of this study was to elucidate the consequences, for soil microbiota (microflora phospholipid fatty acids, protozoa, and nematode functional groups) and for C and N mineralization, of plant community properties such as species richness, resource quality, resource heterogeneity, species identity, and presence of exotics. None of the biotic or abiotic soil variables was related to plant resource heterogeneity. Protozoa were not responsive to any of the plant community traits. Some bacterial and nematode groups were affected by plant characteristics specific to a particular plant species, but no uniform pattern emerged. Invasive and native plants generally were similar with respect to soil variables tested in this study. The lack of clear responses of soil variables to plant community traits indicates that idiosyncratic effects dominate both at the plant and soil biotic level and that generalized plant and soil diversity effects are hard to predict.