Eric Higgs

Novel ecosystems: implications for conservation and restoration.

Many ecosystems are rapidly being transformed into new, non-historical configurations owing to a variety of local and global changes. We discuss how new systems can arise in the face of primarily biotic change (extinction and/or invasion), primarily abiotic change (e.g. land use or climate change) and a combination of both. Some changes will result in hybrid systems retaining some original characteristics as well as novel elements, whereas larger changes will result in novel systems, which comprise different species, interactions and functions. We suggest that these novel systems will require significant revision of conservation and restoration norms and practices away from the traditional place-based focus on existing or historical assemblages.

Managing 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 the current reality of rapid ecosystem change.

Committing to ecological restoration

Efforts around the globe need legal and policy clarification At the September 2014 United Nations Climate Summit, governments rallied around an international agreement—the New York Declaration on Forests—that underscored restoration of degraded ecosystems as an auspicious solution to climate change. Ethiopia committed to restore more than one-sixth of its land. Uganda, the Democratic Republic of Congo, Guatemala, and Colombia pledged to restore huge areas within their borders. In total, parties committed to restore a staggering 350 million hectares by 2030.

The changing role of history in restoration ecology

In the face of rapid environmental and cultural change, orthodox concepts in restoration ecology such as historical fidelity are being challenged. Here we re-examine the diverse roles played by historical knowledge in restoration, and argue that these roles remain vitally important. As such, historical knowledge will be critical in shaping restoration ecology in the future. Perhaps the most crucial role in shifting from the present version of restoration ecology (“v1.0”) to a newer formulation (“v2.0”) is the value of historical knowledge in guiding scientific interpretation, recognizing key ecological legacies, and influencing the choices available to practitioners of ecosystem intervention under conditions of open-ended and rapid change.

Guiding concepts for park and wilderness stewardship in an era of global environmental change.

The major challenge to stewardship of protected areas is to decide where, when, and how to intervene in physical and biological processes, to conserve what we value in these places. To make such decisions, planners and managers must articulate more clearly the purposes of parks, what is valued, and what needs to be sustained. A key aim for conservation today is the maintenance and restoration of biodiversity, but a broader range of values are also likely to be considered important, including ecological integrity, resilience, historical fidelity (ie the ecosystem appears and functions much as it did in the past), and autonomy of nature. Until recently, the concept of “naturalness” was the guiding principle when making conservation-related decisions in park and wilderness ecosystems. However, this concept is multifaceted and often means different things to different people, including notions of historical fidelity and autonomy from human influence. Achieving the goal of nature conservation intended for such...

The Early Settlement of Scotland: Excavations at Morton, Fife.

The Mesolithic settlement at Morton lies some six miles north-north-west of St. Andrews in Fife, Scotland (fig. 1). The area around the site, north-eastern Fife, is surrounded on three sides by water, and projects as a blunt peninsula into the North Sea. The river Eden and the Firth of Tay serve as southern and northern boundaries of this peninsula, which consists today principally of the wind-deposited sands of Tentsmuir. The area of Tentsmuir, now afforested, is one of the relatively few regions in Britain where land is building up into the North Sea, and this process has been in action for many centuries (Sissons, 1967). The Tentsmuir Sands are a prolific source of later prehistoric and early historic finds, the earliest yet known being of the late third millennium B.C. In February 1957, while searching for such material on Tentsmuir, Mr R. Candow of Tayport collected some flints from molehills and other exposures on the high ground of the ‘Old Quarry’ field at Morton Farm (National Grid Reference NO 467257). Surface collections continued to be made until 1963 when excavations of the site were undertaken by Mr Candow in collaboration with Dundee Museum and Art Gallery (Candow, 1966). A total of 41 trenches were excavated between May 1963 and April 1967, and these are shown on the plan of site A (fig. 4, no. 1–41). In November 1967, site B in the same field was discovered and partially excavated (fig. 29, no. 51), before work was suspended and the writer was invited to continue the investigations.

Novel ecosystems: concept or inconvenient reality? A response to Murcia et al.

We are concerned by mischaracterizations, misrepresentations, and selective uses of evidence in a recent critical opinion of ‘the novel ecosystems concept’ [1]. Murcia et al. contend that the concept is poorly developed, has no evidence base, and has little management application and potential negative policy impacts. However, it is more accurate to observe that conceptual development is ongoing (as would be expected in a relatively new area of endeavor), empirical evidence is mounting, many managers find the ideas useful for framing what they observe on the ground, and negative policy impacts are feared rather than observed, despite the growing attention that novel ecosystems are receiving.

Artificial modifications of the coast in response to the Deepwater Horizon oil spill: Quick solutions or long-term liabilities?

The Deepwater Horizon oil spill threatened many coastal ecosystems in the Gulf of Mexico during the spring and summer of 2010. Mitigation strategies included the construction of barrier sand berms, the restriction or blocking of inlets, and the diversion of freshwater from rivers to the coastal marshes and into the ocean, in order to flush away the oil, on the premise that these measures could reduce the quantity of oil reaching sensitive coastal environments such as wetlands or estuaries. These projects result in changes to the ecosystems that they were intended to protect. Long-term effects include alterations of the hydrological and ecological characteristics of estuaries, changes in sediment transport along the coastal barrier islands, the loss of sand resources, and adverse impacts to benthic and pelagic organisms. Although there are no easy solutions for minimizing the impacts of the Deepwater Horizon disaster on coastal ecosystems, we recommend that federal, state, and local agencies return to the ...

Changing Nature: Novel Ecosystems, Intervention, and Knowing When to Step Back

Climate change, species invasions, and changes in social practices and cultural beliefs about nature are creating new ecosystems, some of which have no apparent roots in the past. The emergence of hybrid (familiar ecosystems with new combinations) and novel (unfamiliar) ecosystems challenges conventional ecological restoration practices, which places reliance on robust notions of historical fidelity. There is an extent to which the science and practice of restoration can be adapted to cope with significant change and discontinuities, but beyond a certain point, yet unknowable, it may be necessary to look ahead to emerging practices that blend the important qualities of restoration with wild or regenerative design.

A comparative evaluation of feature detectors on historic repeat photography

This study reports on the quantitative evaluation of a set of state-of-the-art feature detectors in the context of repeat photography. Unlike most related work, the proposed study assesses the performance of feature detectors when intra-pair variations are uncontrolled and due to a variety of factors (landscape change, weather conditions, different acquisition sensors). There is no systematic way to model the factors inducing image change. The proposed evaluation is performed in the context of image matching, i.e. in conjunction with a descriptor and matching strategy. Thus, beyond just comparing the performance of these detectors, we also examine the feasibility of feature-based matching on repeat photography. Our dataset consists of a set of repeat and historic images pairs that are representative for the database created by the Mountain Legacy Project www.mountainlegacy.ca.