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Restoration Goals (restoration + goal)

Distribution by Scientific Domains

Life Sciences	81%

Selected Abstracts

Linking ecological theory with stream restoration

FRESHWATER BIOLOGY, Issue 4 2007
P. S. LAKE
Summary 1. Faced with widespread degradation of riverine ecosystems, stream restoration has greatly increased. Such restoration is rarely planned and executed with inputs from ecological theory. In this paper, we seek to identify principles from ecological theory that have been, or could be, used to guide stream restoration. 2. In attempts to re-establish populations, knowledge of the species' life history, habitat template and spatio-temporal scope is critical. In many cases dispersal will be a critical process in maintaining viable populations at the landscape scale, and special attention should be given to the unique geometry of stream systems 3. One way by which organisms survive natural disturbances is by the use of refugia, many forms of which may have been lost with degradation. Restoring refugia may therefore be critical to survival of target populations, particularly in facilitating resilience to ongoing anthropogenic disturbance regimes. 4. Restoring connectivity, especially longitudinal connectivity, has been a major restoration goal. In restoring lateral connectivity there has been an increasing awareness of the riparian zone as a critical transition zone between streams and their catchments. 5. Increased knowledge of food web structure , bottom-up versus top-down control, trophic cascades and subsidies , are yet to be applied to stream restoration efforts. 6. In restoration, species are drawn from the regional species pool. Having overcome dispersal and environmental constraints (filters), species persistence may be governed by local internal dynamics, which are referred to as assembly rules. 7. While restoration projects often define goals and endpoints, the succession pathways and mechanisms (e.g. facilitation) by which these may be achieved are rarely considered. This occurs in spite of a large of body of general theory on which to draw. 8. Stream restoration has neglected ecosystem processes. The concept that increasing biodiversity increases ecosystem functioning is very relevant to stream restoration. Whether biodiversity affects ecosystem processes, such as decomposition, in streams is equivocal. 9. Considering the spatial scale of restoration projects is critical to success. Success is more likely with large-scale projects, but they will often be infeasible in terms of the available resources and conflicts of interest. Small-scale restoration may remedy specific problems. In general, restoration should occur at the appropriate spatial scale such that restoration is not reversed by the prevailing disturbance regime. 10. The effectiveness and predictability of stream ecosystem restoration will improve with an increased understanding of the processes by which ecosystems develop and are maintained. Ideas from general ecological theory can clearly be better incorporated into stream restoration projects. This will provide a twofold benefit in providing an opportunity both to improve restoration outcomes and to test ecological theory. [source]

Integrating Soil Ecological Knowledge into Restoration Management

RESTORATION ECOLOGY, Issue 4 2008
Liam Heneghan
Abstract The variability in the type of ecosystem degradation and the specificity of restoration goals can challenge restorationists' ability to generalize about approaches that lead to restoration success. The discipline of soil ecology, which emphasizes both soil organisms and ecosystem processes, has generated a body of knowledge that can be generally useful in improving the outcomes of restoration despite this variability. Here, we propose that the usefulness of this soil ecological knowledge (SEK) for restoration is best considered in the context of the severity of the original perturbation, the goals of the project, and the resilience of the ecosystem to disturbance. A straightforward manipulation of single physical, chemical, or biological components of the soil system can be useful in the restoration of a site, especially when the restoration goal is loosely defined in terms of the species and processes that management seeks to achieve. These single-factor manipulations may in fact produce cascading effects on several ecosystem attributes and can result in unintended recovery trajectories. When complex outcomes are desired, intentional and holistic integration of all aspects of the soil knowledge is necessary. We provide a short roster of examples to illustrate that SEK benefits management and restoration of ecosystems and suggest areas for future research. [source]

Habitat-mediated size selection in endangered Atlantic salmon fry: selectional restoration assessment

EVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 4 2010
Michael M. Bailey
Abstract Preservation of adaptive variation is a top priority of many species restoration programs, but most restoration activities are conducted without direct knowledge of selection that might foster or impair adaptation and restoration goals. In this study, we quantified geographic variation in selection on fry size of endangered Atlantic salmon (Salmo salar) during the 6-week period immediately following stocking in the wild. We also used a model selection approach to assess whether habitat variables influence patterns of such selection. We found evidence for significant size-selection in five out of six selection trials. Interestingly, the strength and pattern of selection varied extensively among sites, and model selection suggested that this variation in phenotypic selection was related to geographic variation in the presence of large woody debris and the slope of the stream gradient. The strong selection differentials we observed should be a concern for endangered salmon restoration, whether they reflect natural processes and an opportunity to maintain adaptation, or an indicator of the potentially deleterious phenotypic consequences of hatchery practices. [source]

Forest change and stream fish habitat: lessons from ,Olde' and New England

JOURNAL OF FISH BIOLOGY, Issue 2005
K. H. Nislow
The North Atlantic region has a long history of land use change that has influenced and will continue to influence stream ecosystems and fisheries production. This paper explores and compares the potential consequences of changes in forest cover for fish production in upland, coldwater stream environments in New England, U.S.A. and the British Isles, two regions which share important similarities with respect to overall physical, biotic and socio-economic setting. Both regions were extensively deforested and essentially no extensive old-growth forest stands remain. In New England, recovering forests, consisting almost entirely of naturally-regenerated native species, now cover >60% of the landscape. Associated with this large-scale reforestation, open landscapes, common in the 19th and first half the 20th century, are currently rare and declining in this region. In the British Isles, forests still cover <20% of the landscape, and existing forests largely consist of exotic conifer plantations stocked at high stand densities and harvested at frequent rotations. While forest restoration and conservation is frequently recommended as a fisheries habitat conservation and restoration tool, consideration of the way in which forests affect essential aspects of fish habitat suggests that response of upland stream fish to landscape change is inherently complex. Under certain environmental settings and reforestation practices, conversion of open landscapes to young-mature forests can negatively impact fish production. Further, the effects of re-establishing old-growth forests are difficult to predict for the two regions (due to the current absence of such landscapes), and are likely to depend strongly on the extent to which critical ecosystem attributes (large-scale disturbances, fish migrations, keystone species, large woody debris recruitment) are allowed to be re-established. Understanding these context-dependencies is critical for predicting fish responses, and should help managers set realistic conservation, management and restoration goals. Management may best be served by promoting a diversity of land cover types in a way that emulates natural landscape and disturbance dynamics. This goal presents very different challenges in New England and the British Isles due to differences in current and predicted land use trajectories, along with differences in ecological context and public perception. [source]

Floodplain agricultural systems: functionality, heritage and conservation

JOURNAL OF FLOOD RISK MANAGEMENT, Issue 3 2010
H.F. Cook
Abstract Floodplain infrastructural features reduce flood risk and have the potential to enhance habitat, biodiversity, water quality and provide societal benefits. Man-made water management systems common in southern England are both flood tolerant and form part of the functional floodplain. Historic floodplain features should be incorporated into agri-environmental policy, as climate change and increasing climate variability makes flood detention areas ever more desirable. Of major importance are floodplain meadows, grazing marshes, water meadows and riparian vegetation, and there is a trend to restore river channels to more natural conditions. This paper describes the operation of historic floodplain water management systems and considers the features associated with canals and mills. The major themes in achieving conservation and restoration goals are presented, and it is demonstrated that a refinement of policies on the ground is required. [source]

Integrating Soil Ecological Knowledge into Restoration Management

Altering Light and Soil N to Limit Phalaris arundinacea Reinvasion in Sedge Meadow Restorations

RESTORATION ECOLOGY, Issue 4 2008
Basil V. Iannone III
Abstract Efforts to eradicate invasive plants in restorations can unintentionally create conditions that favor reinvasion over the establishment of desired species, especially when remnant invasive propagules persist. Reducing resources needed by the invader for seedling establishment, however, may be an effective strategy to prevent reinvasion. Propagules of Phalaris arundinacea persist after removal from sedge meadow wetlands and reestablish quickly in posteradication conditions, hindering community restoration. A study was conducted in two experimental wetlands with controlled hydrologic regimes to determine if reducing light by sowing short-lived, nonpersistent native cover crops or immobilizing soil N by incorporating soil,sawdust amendments can prevent Phalaris reinvasion, allowing native communities to recover. A 10-species perennial target community and Phalaris were sown with high-diversity, low-diversity, or no cover crops in soils with or without sawdust, and seedling emergence, establishment, and growth were measured. High-diversity cover crops reduced light, decreasing Phalaris and target community seedling establishment by 89 and 57%, respectively. Short-term nitrogen reduction in sawdust-amended soils delayed Phalaris seedling emergence and decreased Phalaris seedling establishment by 59% but did not affect total target community seedling establishment. The target community reduced Phalaris seedling establishment as effectively as cover crops did. In plots where the target community was grown, amending soils with sawdust further reduced Phalaris seedling growth but not establishment. Results show that use of cover crops can reduce seedling establishment of desired species and is counterproductive to restoration goals. Further, establishing target species is more important and practical for limiting Phalaris reinvasion than is immobilizing nitrogen. [source]

The Challenge to Restore Processes in Face of Nonlinear Dynamics,On the Crucial Role of Disturbance Regimes

RESTORATION ECOLOGY, Issue 2 2007
*Article first published online: 14 MAY 200, Anke Jentsch
Abstract Increasingly, restoration ecologists and managers are challenged to restore ecological processes that lead to self-sustaining ecosystem dynamics. Due to changing environmental conditions, however, restoration goals need to include novel regimes beyond prior reference conditions or reference dynamics. In face of these fundamental challenges in process-based restoration ecology, disturbance ecology can offer useful insights. Here, I discuss the contribution of disturbance ecology to understanding assembly rules, ecosystem dynamics, regime shifts, and nonlinear dynamics. Using the patch and multipatch concept, all insights are organized according to two spatial and two temporal categories: "patch,event,""patch,multievent,""multipatch,event," and "multipatch,multievent." This concept implies the consideration of both spatial patterns and temporal rhythms inside and outside of a restoration site. Emerging issues, such as uncoupling of internal and external dynamics, are considered. [source]

Stream Restoration in the Upper Midwest, U.S.A.

RESTORATION ECOLOGY, Issue 4 2006
Gretchen G. Alexander
Abstract Restoration activities intended to improve the condition of streams and rivers are widespread throughout the Upper Midwest, U.S.A. As with other regions, however, little information exists regarding types of activities and their effectiveness. We developed a database of 1,345 stream restoration projects implemented from the years 1970 to 2004 for the states of Michigan, Ohio, and Wisconsin in order to analyze regional trends in goals, presence of monitoring, spatial distribution, size, and cost of river restoration projects. We found that data on individual projects were fragmented across multiple federal, state, and county agencies, as well as nonprofit groups and consulting firms. The most common restoration goals reported for this region were in-stream habitat improvement, bank stabilization, water-quality management, and dam removal. The former two were most common in Michigan and Wisconsin, where salmonid fisheries enhancement appeared to be an important concern, whereas water-quality management was most frequent in Ohio. The most common restoration activities were the use of sand traps and riprap, and other common activities were related to the improvement of fish habitat. The median cost was $12,957 for projects with cost data, and total expenditures since 1990 were estimated at $444 million. Over time, the cost of individual projects has increased, whereas the median size has decreased, suggesting that restoration resources are being spent on smaller, more localized, and more expensive projects. Only 11% of data records indicated that monitoring was performed, and more expensive projects were more likely to be monitored. Standardization of monitoring and record keeping and dissemination of findings are urgently needed to ensure that dollars are well spent and restoration effectiveness is maximized. [source]

Sampling Techniques Influence Understory Plant Trajectories After Restoration: An Example from Ponderosa Pine Restoration

RESTORATION ECOLOGY, Issue 4 2003
Julie E. Korb
Abstract Although there is no one correct technique for sampling vegetation, the sampling design chosen may greatly influence the conclusions researchers can draw from restoration treatments. Considerations when designing vegetation sampling protocol include determining what sampling attributes to measure, the size and shape of the sampling plot, the number of replicates and their location within the study area, and the frequency of sampling. We installed 20 point-intercept transects (50-m long), 8 belt transects (10 × 50 m), 10 adapted Daubenmire transects (four 0.5 × 2-m plots), and 4 modified-Whittaker plots (20 × 50 m with smaller nested plots) in treatment and control units to measure understory herbaceous response in a forest restoration experiment that tested different treatments. Point-intercept transects on average recorded at least twice as much plant cover as did adapted Daubenmire transects and modified-Whittaker plots taken at the same location for all control and treatment units. Point-intercept transects and adapted Daubenmire plots on average captured fewer rare and exotic species in the control and treatment units in comparison with the belt transects and modified-Whittaker plots. Modified-Whittaker plots captured the highest species richness in all units. Early successional understory response to restoration treatments was likely masked by the response of the herbaceous community to yearly climatic variation (dry vs. wet years). Species richness and abundance were higher in wet years than dry years for all control and treatment units. Our results illustrate that sampling techniques can greatly influence perceptions of understory plant trajectories and therefore the interpretation of whether restoration goals have been achieved. In addition, our results suggest that restoration monitoring needs to be conducted for a sufficient length of time so that restoration treatment responses can be detected. [source]

Linking ecological function to species composition in ecological restoration: Seed removal by ants in recreated woodland

AUSTRAL ECOLOGY, Issue 7 2009
BORIS LOMOV
Abstract Evaluations of ecological restoration typically focus on associating measures of structural properties of ecosystems (e.g. species diversity) with time since restoration efforts commenced. Such studies often conclude a failure to achieve restoration goals without examining functional performance of the organism assemblages in question. We compared diversity and composition of ant assemblages and the rates of seed removal by ants in pastures, 4- to 10-year old revegetated areas and remnants of Cumberland Plain Woodland, and an endangered ecological community in Sydney, Australia. Ant assemblages of forest remnant sites had significantly higher species richness, significantly different species composition and a more complex functional group structure in comparison with ant assemblages of pasture and revegetated sites, which did not differ significantly. However, the rates of seed removal by ants in revegetated sites were similar to those in forest remnants, with the rates in pasture sites being significantly lower. Approximately, one-third of all ant species were observed to remove seeds. Forest remnant sites had significantly different assemblages of seed removing ant species from those in pasture and revegetated sites. These results demonstrate that similar ant assemblages of unrestored and restored areas can function differently, depending on habitat context. Evaluation of restoration success by quantifying ecosystem structure and function offers more insights into ecosystem recovery than reliance on structural data alone. [source]