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Restoration Sites (restoration + site)
Selected AbstractsEVAPOTRANSPIRATION DYNAMICS AT AN ECOHYDROLOGICAL RESTORATION SITE: AN ENERGY BALANCE AND REMOTE SENSING APPROACH,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 3 2006Jason W. Oberg ABSTRACT: Little work is reported where spatial methods are employed to monitor evapotranspiration (ET) changes as a result of vegetation and wetland restoration. A remote sensing approach with the Surface Energy Balance Algorithm for Land (SEBAL) for estimating ET at The Nature Conservancy's Glacial Ridge prairie-wetland restoration site in northwestern Minnesota is presented. The calibrated 24-hour ET from SEBAL was estimated with an average error of prediction of ,4.3 percent. Monthly, interseasonal, and seasonal ET for the period of June to September (2000 to 2003) from three adjacent land-uses: a hydrologic control preserved wetland; a treated or restored site; and a nontreated or impacted wetland, were used in the study. Results from comparing ET behavior to the preserve suggest restoration efforts have affected monthly and seasonal ET within the treated site. Spatial average standard deviations of the seasonal ET within the preserve, treated, and nontreated sites give 47.3, 75.7, and 109.9 mm, respectively, suggesting hydrologic stabilization within the treated site. Monthly and interseasonal comparisons show similar behavior to that of the seasonal data, where monthly correlations suggest increasing agreement within the treated site, approaching those within the preserve. [source] MARSH DEVELOPMENT AT RESTORATION SITES ON THE WHITE MOUNTAIN APACHE RESERVATION, ARIZONA,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 6 2003Jonathan W. Long ABSTRACT: To prioritize sites for riparian restoration, resource managers need to understand how recovery processes vary within landscapes. Complex relationships between watershed conditions and riparian development make it difficult to predict the outcomes of restoration treatments in the semiarid Southwest. Large floods in 1993 scoured riparian areas in the Carrizo watershed on the White Mountain Apache Reservation in east-central Arizona. We evaluated recovery at three of these sites using repeated photographs and measurements of channel cross sections and stream-side vegetation along permanent transects. The sites were mapped as lying on the same soil type, had similar streamside vegetative communities, and were similarly treated through livestock exclusion and supplemental seeding. However, the sites and individual reaches within the sites followed strikingly different development paths. Dramatic recovery occurred at a perennial reach where cover of emergent wetland plants increased from 4.7 percent (standard error = 0.8 percent) in October 1995 to 55.5 percent (standard error = 2.7 percent) in September 2001. At several other reaches, geologic and hydro geomorphic characteristics of the sites limited inputs of fine sediment or surface water, resulting in modest or negligible increases in emergent cover. Recovery efforts for highly valued marshlands in this region should prioritize perennial reaches in low gradient valleys where salty sediments are abundant. [source] Triad case study: Marine Corps Base Camp PendletonREMEDIATION, Issue 1 2004Adrianne V. Saboya The U.S. Navy Public Works Center (PWC) Environmental Department, San Diego, California, is home to the Navy West Coast Site Characterization and Analysis Penetrometer System (SCAPS). SCAPS has been extensively used at several Navy sites since 1995 to provide real-time, high-density data sets. The U.S. Environmental Protection Agency's Triad approach provided an ideal framework for optimizing the use of the Navy SCAPS during a volatile organic compound (VOC) source investigation at Installation Restoration Site 1114 at Marine Corps Base Camp Pendleton. All three elements of Triad,systematic planning, dynamic work strategy, and use of real-time measurement tools,were implemented to manage decision uncertainty and expedite the site management process. The investigation was conducted using the Navy SCAPS, outfitted with a cone penetrometer, membrane interface probe, and a direct sampling ion trap mass spectrometry detector, which allowed for real- time collection of over 690 feet of continuous lithologic information and VOC concentration data. These data were used collaboratively with 24-hour turnaround US EPA 8260B VOC groundwater results from temporary direct- push wells to support the conclusion of a limited source area. Implementation of the Triad approach for this investigation provided an expedited high-density data set and a refined conceptual site model (CSM) in real time that resulted in cost savings estimated at $2.5M and reduction of the site characterization and cleanup schedule by approximately three years. This project demonstrates how the US EPA's Triad approach can be applied to streamline the site characterization and cleanup process while appropriately managing decision uncertainty in support of defensible site decisions. © 2004 Wiley Periodicals, Inc. [source] Woody Encroachment Removal from Midwestern Oak Savannas Alters Understory Diversity across Space and TimeRESTORATION ECOLOGY, Issue 1 2010Lars A. Brudvig Recovering biodiversity is a common goal during restoration; however, for many ecosystems, it is not well understood how restoration influences species diversity across space and time. I examined understory species diversity and composition after woody encroachment removal in a large-scale savanna restoration experiment in central Iowa, United States. Over a 4-year time series, restoration had profound effects across space and time, increasing richness at local and site-level scales. Restoration sites had increased , (within sample) Simpson's diversity and , and , (site level) species richness relative to control sites, although , and , (among sample) Simpson's diversity, , richness, and , species evenness were not affected. Changes in richness were driven by graminoids at the , and , scales and woody species (and some evidence for forbs) at the , scale. Interestingly, indicator species analysis revealed that at least some species from all functional groups were promoted by restoration, although no species were significant indicators of pre-treatment or control sites. Both savanna and nonsavanna species were indicators of restored sites. Restoration promoted exotic species at both scales, although species with spring phenologies were unaffected. Woody encroachment removal may be a means to promote species establishment in savannas; however, in this study, it resulted in establishment and proliferation of native and exotic and savanna and nonsavanna species. Future work might consider reintroduction of key savanna species to supplement those that have established. Work like this demonstrates the utility of restoration experiments for conducting research on large- and multiscale processes, such as species diversity. [source] Spatiotemporal dynamics of evapotranspiration at the Glacial Ridge prairie restoration in northwestern MinnesotaHYDROLOGICAL PROCESSES, Issue 7 2006Assefa M. Melesse Abstract Among the various indicators of success in wetland restoration, hydrology is the most important and relatively easy to monitor. Evapotranspiration (ET) was used to assess the ecohydrologic changes at the Glacial Ridge prairie restoration site in northwestern Minnesota. Twelve Landsat images from 2000,03 for the months of June, July and August were used to study the spatial ET changes. Spatial monthly and seasonal ET were estimated using a surface energy budget technique from Landsat images. Five sub-basins within the study area were delineated to represent the different conditions of the wetlands. Their spatial and temporal ET responses to the restoration activities (native species planting, burning and ditch closures) were studied. Spatial statistics showing mean and standard deviation of monthly ET were computed. Comparisons were made between these watersheds and the preserved sub-watershed of the study area. The average annual ET increases for the five sub-basins were in the range of 9% (2002,03) to 25% (2001,02). Over the study period, ET increased by nearly 50%. After considering the effect of variations in precipitation, wind speed and solar radiation on the resulting ET, the results show that ET increased in recent years as result of the restoration activities. Copyright © 2005 John Wiley & Sons, Ltd. [source] Plant colonization after managed realignment: the relative importance of diaspore dispersalJOURNAL OF APPLIED ECOLOGY, Issue 4 2005MINEKE WOLTERS Summary 1Deliberate breaching of sea defences is frequently practised with the aim of restoring salt-marsh vegetation on previously embanked land. However, experience so far has shown that it may take several years before salt-marsh vegetation is fully established, and it is possible that limited diaspore dispersal plays a role in this. In order to ascertain whether salt-marsh development may be constrained by limited diaspore dispersal, we studied the dispersal of salt-marsh species by tidal water. 2From October 2001 to the end of March 2002 a total of 38 species, of which 18 were salt-marsh species, was trapped in a restoration site and adjacent marsh. Aster tripolium, Limonium vulgare, Puccinellia maritima, Salicornia spp., Spergularia media and Suaeda maritima were the most abundant salt-marsh species, with more than 3 diaspores m,2 trapped during the study period. 3For most species, the number of diaspores trapped was representative of their abundance in nearby vegetation. Hence, despite the potential for long-distance transport by tidal water, our results indicate a predominantly local dispersal of salt-marsh species. 4Synthesis and applications. For the restoration of salt-marsh vegetation after de-embankment, relatively rapid colonization may be expected from pioneer and low-marsh species, provided they are present in a nearby source area and the restoration site is at the appropriate altitude. The establishment of species absent from the adjacent marsh may be dependent on the presence of birds or humans as the main dispersal agents. Breaching of sea defences should preferably take place before or during September, in order to take advantage of the peak in dispersal of salt-marsh species in the first year after breaching. [source] Habitat fragmentation and adaptation: a reciprocal replant,transplant experiment among 15 populations of Lychnis flos-cuculiJOURNAL OF ECOLOGY, Issue 5 2008Gillianne Bowman Summary 1Habitat fragmentation and variation in habitat quality can both affect plant performance, but their effects have rarely been studied in combination. We thus examined plant performance in response to differences in habitat quality for a species subject to habitat fragmentation, the common but declining perennial herb Lychnis flos-cuculi. 2We reciprocally transplanted plants between 15 fen grasslands in north-east Switzerland and recorded plant performance for 4 years. 3Variation between the 15 target sites was the most important factor and affected all measures of plant performance in all years. This demonstrates the importance of plastic responses to habitat quality for plant performance. 4Plants from smaller populations produced fewer rosettes than plants from larger populations in the first year of the replant,transplant experiment. 5Plant performance decreased with increasing ecological difference between grassland of origin and target grassland, indicating adaptation to ecological conditions. In contrast, plant performance was not influenced by microsatellite distance and hardly by geographic distance between grassland of origin and target grassland. 6Plants originating from larger populations were better able to cope with larger ecological differences between transplantation site and site of origin. 7Synthesis: In addition to the direct effects of target grasslands, both habitat fragmentation, through reduced population size, and adaptation to habitats of different quality, contributed to the performance of L. flos-cuculi. This underlines that habitat fragmentation also affects species that are still common. Moreover, it suggests that restoration projects involving L. flos-cuculi should use plant material from large populations living in habitats similar to the restoration site. Finally, our results bring into question whether plants in small habitat remnants will be able to cope with future environmental change. [source] The Challenge to Restore Processes in Face of Nonlinear Dynamics,On the Crucial Role of Disturbance RegimesRESTORATION 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] Restoring Stream Ecosystems: Lessons from a Midwestern StateRESTORATION ECOLOGY, Issue 3 2004Ashley H. Moerke Abstract Reach-scale stream restorations are becoming a common approach to repair degraded streams, but the effectiveness of these projects is rarely evaluated or reported. We surveyed governmental, private, and nonprofit organizations in the state of Indiana to determine the frequency and nature of reach-scale stream restorations in this midwestern U.S. state. For 10 attempted restorations in Indiana, questionnaires and on-site assessments were used to better evaluate current designs for restoring stream ecosystems. At each restoration site, habitat and water quality were evaluated in restored and unrestored reaches. Our surveys identified commonalities across all restorations, including the type of restoration, project goals, structures installed, and level of monitoring conducted. In general, most restorations were described as stream-relocation projects that combined riparian and in-stream enhancements. Fewer than half of the restorations conducted pre- or post-restoration monitoring, and most monitoring involved evaluations of riparian vegetation rather than aquatic variables. On-site assessments revealed that restored reaches had significantly lower stream widths and greater depths than did upstream unrestored reaches, but riparian canopy cover often was lower in restored than in unrestored reaches. This study provides basic information on midwestern restoration strategies, which is needed to identify strengths and weaknesses in current practices and to better inform future stream restorations. [source] Salt Marsh Restoration in Connecticut: 20 Years of Science and ManagementRESTORATION ECOLOGY, Issue 3 2002R. Scott Warren Abstract In 1980 the State of Connecticut began a tidal marsh restoration program targeting systems degraded by tidal restrictions and impoundments. Such marshes become dominated by common reed grass (Phragmites australis) and cattail (Typha angustifolia and T. latifolia), with little ecological connection to Long Island Sound. The management and scientific hypothesis was that returning tidal action, reconnecting marshes to Long Island Sound, would set these systems on a recovery trajectory. Specific restoration targets (i.e., pre-disturbance conditions or particular reference marshes) were considered unrealistic. However, it was expected that with time restored tides would return ecological functions and attributes characteristic of fully functioning tidal salt marshes. Here we report results of this program at nine separate sites within six marsh systems along 110 km of Long Island Sound shoreline, with restoration times of 5 to 21 years. Biotic parameters assessed include vegetation, macroinvertebrates, and use by fish and birds. Abiotic factors studied were soil salinity, elevation and tidal flooding, and soil water table depth. Sites fell into two categories of vegetation recovery: slow, ca. 0.5%, or fast, more than 5% of total area per year. Although total cover and frequency of salt marsh angiosperms was positively related to soil salinity, and reed grass stand parameters negatively so, fast versus slow recovery rates could not be attributed to salinity. Instead, rates appear to reflect differences in tidal flooding. Rapid recovery was characterized by lower elevations, greater hydroperiods, and higher soil water tables. Recovery of other biotic attributes and functions does not necessarily parallel those for vegetation. At the longest studied system (rapid vegetation recovery) the high marsh snail Melampus bidentatus took two decades to reach densities comparable with a nearby reference marsh, whereas the amphipod Orchestia grillus was well established on a slow-recovery marsh, reed grass dominated after 9 years. Typical fish species assemblages were found in restoration site creeks and ditches within 5 years. Gut contents of fish in ditches and on the high marsh suggest that use of restored marsh as foraging areas may require up to 15 years to reach equivalence with reference sites. Bird species that specialize in salt marshes require appropriate vegetation; on the oldest restoration site, breeding populations comparable with reference marshland had become established after 15 years. Use of restoration sites by birds considered marsh generalists was initially high and was still nearly twice that of reference areas even after 20 years. Herons, egrets, and migratory shorebirds used restoration areas extensively. These results support our prediction that returning tides will set degraded marshes on trajectories that can bring essentially full restoration of ecological functions. This can occur within two decades, although reduced tidal action can delay restoration of some functions. With this success, Connecticut's Department of Environmental Protection established a dedicated Wetland Restoration Unit. As of 1999 tides have been restored at 57 separate sites along the Connecticut coast. [source] Decomposition of Sarcocornia quinqueflora on an Iron-Smelting Slag SubstrateRESTORATION ECOLOGY, Issue 1 2002T. M. Dick Abstract Restoration of salt marsh habitat is becoming more common in Australia. However, little is known about restoring salt marshes on substrates contaminated by slag from iron smelting, which could affect microbial activity. This study, conducted near Newcastle, Australia, compares initial C, N, and P mass and decomposition of Sarcocornia quinqueflora (glasswort or samphire) from (1) a restoration site with a slag-and-mud substrate, (2) the restoration site's donor marsh, and (3) other nearby sites sampled to provide information on background variability. A litterbag technique with a 180-day incubation period was used to quantify total, C, N, and P mass losses from decomposition. Although there were significant differences between sites in initial N mass and loss of C and P over the period of our study, the presence of slag did not slow decomposition rates as measured using litterbags. Further work is needed to assess other aspects of wetland structure and function on slag substrates. [source] Combined definition of seed transfer guidelines for ecological restoration in the French PyreneesAPPLIED VEGETATION SCIENCE, Issue 1 2010S. Malaval Abstract Question: Can genetic tools combined with phytogeography help to define local plants and how geographically close the source population should be to the restoration site? Location: Subalpine and alpine French Pyrenees. Methods: The main phytogeographic boundaries in the French Pyrenees described by different authors were studied and this geographic pattern was compared with the results of genetic analysis for the four Pyrenean plants studied (Trifolium alpinum, Festuca eskia, Festuca gautieri and Rumex scutatus), based on random amplified polymorphic DNA (RAPD) marker analysis, unweighted pair-group method with arithmetic averages (UPGMA) analysis and Mantel correlograms comparing geographic and genetic distances. Results: The genetic analysis allowed definition of two main evolutionarily significant units (ESUs) for the plants under study. Although the limit between the two zones was slightly variable according to the species considered, an eastern and a western ESU was consistently observed. This delineation was concordant with the main phytogeographic boundaries of the French Pyrenees. Conclusion: RAPD markers and associated Mantel correlograms can be useful to draw ESUs for individual species when the sampling intensity is relatively dense, and similarities were revealed between species sharing the same distribution range. This delineation allowed integration of infraspecific plant variation in the management of natural resources for revegetation in the Pyrenees. Nevertheless, caution is needed for the establishment of seed pools in order to maximize genetic diversity in each of the pools during collection and production. [source] Are Ants Useful Indicators of Restoration Success in Temperate Grasslands?RESTORATION ECOLOGY, Issue 3 2010Kate C. Fagan Assessments of restoration are usually made through vegetation community surveys, leaving much of the ecosystem underexamined. Invertebrates, and ants in particular, are good candidates for restoration evaluation because they are sensitive to environmental change and are particularly important in ecosystem functioning. The considerable resources currently employed in restoring calcareous grassland on ex-arable land mean that it is important to gather as much information as possible on how ecosystems change through restoration. We compared ant communities from 40 ex-arable sites where some form of restoration work had been implemented between 2 and 60 years previously, with 40 paired reference sites of good quality calcareous grassland with no history of improvement or cultivation. A total of 11 ant species were found, but only two of these were found to be significantly different in abundance between restoration and reference sites: Myrmica sabuleti was more likely to be present in reference sites, whereas Lasius niger was more likely to be found in restoration sites. Myrmica sabuleti abundance was significantly positively correlated with age of restoration sites. The potential number of ant species found in temperate grasslands is small, limiting the information their assemblages can provide about ecosystem change. However, M. sabuleti is a good indicator species for calcareous grassland restoration success and, alongside information from the plant community, could increase the confidence with which restoration success is judged. We found the survey to be quick and simple to carry out and recommend its use. [source] Soil Organism and Plant Introductions in Restoration of Species-Rich Grassland CommunitiesRESTORATION ECOLOGY, Issue 2 2009Paul Kardol Abstract Soil organisms can strongly affect competitive interactions and successional replacements of grassland plant species. However, introduction of whole soil communities as management strategy in grassland restoration has received little experimental testing. In a 5-year field experiment at a topsoil-removed ex-arable site (receptor site), we tested effects of (1) spreading hay and soil, independently or combined, and (2) transplanting intact turfs on plant and soil nematode community development. Material for the treatments was obtained from later successional, species-rich grassland (donor site). Spreading hay affected plant community composition, whereas spreading soil did not have additional effects. Plant species composition of transplanted turfs became less similar to that in the donor site. Moreover, most plants did not expand into the receiving plots. Soil spreading and turf transplantation did not affect soil nematode community composition. Unfavorable soil conditions (e.g., low organic matter content and seasonal fluctuations in water level) at the receptor site may have limited plant and nematode survival in the turfs and may have precluded successful establishment outside the turfs. We conclude that introduction of later successional soil organisms into a topsoil-removed soil did not facilitate the establishment of later successional plants, probably because of the "mismatch" in abiotic soil conditions between the donor and the receptor site. Further research should focus on the required conditions for establishment of soil organisms at restoration sites in order to make use of their contribution to grassland restoration. We propose that introduction of organisms from "intermediate" stages will be more effective as management strategy than introduction of organisms from "target" stages. [source] Wetland Restoration in the New Millennium: Do Research Efforts Match Opportunities?RESTORATION ECOLOGY, Issue 3 2008Kelly I. Wagner Abstract Of 311 papers on wetland restoration, only 15 concerned large-scale experimentation in restoration sites. Most papers described what happened, reported on small field experiments, or discussed restoration targets. While these are important topics, our opinion is that we lose significant opportunities to learn how to recover populations, community structure, and ecosystem processes, and we limit our ability to document variability and whole-system responses, when we do not experiment at large scales. We suggest that, wherever possible, large projects facilitate field tests of alternative restoration approaches. Furthermore, we encourage researchers to take advantage of major restoration efforts by conducting large field experiments, assessing multiple responses, and offering restoration guidance in an adaptive framework. [source] Diminishing Spatial Heterogeneity in Soil Organic Matter across a Prairie Restoration ChronosequenceRESTORATION ECOLOGY, Issue 2 2005Diana R. Lane Abstract Habitat restoration resulting in changes in plant community composition or species dominance can affect the spatial pattern and variability of soil nutrients. Questions about how these changes in soil spatial heterogeneity develop over time at restoration sites, however, remain unaddressed. In this study, a geostatistical approach was used to quantify changes over time in the spatial heterogeneity of soil organic matter (SOM) across a 26-year chronosequence of tallgrass prairie restoration sites at FermiLab, outside of Chicago, Illinois. We used total soil N and C as an index of the quantity of SOM. We also examined changes in C:N ratio, which can influence the turnover of SOM. Specifically, the spatial structure of total N, total C, and C:N ratio in the top 10 cm of soil was quantified at a macroscale (minimum spacing of 1.5 m) and a microscale (minimum spacing of 0.2 m). The magnitude of spatial heterogeneity (MSH) was characterized as the proportion of total sample variation explained by spatially structured variation. At the macroscale, the MSH for total N decreased with time since restoration (r2= 0.99, p < 0.001). The decrease in spatial heterogeneity over time corresponded with a significant increase in the dominance of the C4 grasses. At the microscale, there was significant spatial structure for total N at the 4-year-old, 16-year-old, and 26-year-old sites, and significant spatial structure for total C at the 16-year-old and 26-year-old sites. These results suggest that an increase in dominance of C4 grasses across the chronosequence is homogenizing organic matter variability at the field scale while creating fine-scale patterns associated with the spacing of vegetation. Areas of higher soil moisture were associated with higher soil N and C at the two oldest restoration sites and at the native prairie site, potentially suggesting patches of increased belowground productivity in areas of higher soil moisture. This study is one of the first to report significant changes over time in the spatial structure of organic matter in response to successional changes initiated by restoration. [source] Salt Marsh Restoration in Connecticut: 20 Years of Science and ManagementRESTORATION ECOLOGY, Issue 3 2002R. Scott Warren Abstract In 1980 the State of Connecticut began a tidal marsh restoration program targeting systems degraded by tidal restrictions and impoundments. Such marshes become dominated by common reed grass (Phragmites australis) and cattail (Typha angustifolia and T. latifolia), with little ecological connection to Long Island Sound. The management and scientific hypothesis was that returning tidal action, reconnecting marshes to Long Island Sound, would set these systems on a recovery trajectory. Specific restoration targets (i.e., pre-disturbance conditions or particular reference marshes) were considered unrealistic. However, it was expected that with time restored tides would return ecological functions and attributes characteristic of fully functioning tidal salt marshes. Here we report results of this program at nine separate sites within six marsh systems along 110 km of Long Island Sound shoreline, with restoration times of 5 to 21 years. Biotic parameters assessed include vegetation, macroinvertebrates, and use by fish and birds. Abiotic factors studied were soil salinity, elevation and tidal flooding, and soil water table depth. Sites fell into two categories of vegetation recovery: slow, ca. 0.5%, or fast, more than 5% of total area per year. Although total cover and frequency of salt marsh angiosperms was positively related to soil salinity, and reed grass stand parameters negatively so, fast versus slow recovery rates could not be attributed to salinity. Instead, rates appear to reflect differences in tidal flooding. Rapid recovery was characterized by lower elevations, greater hydroperiods, and higher soil water tables. Recovery of other biotic attributes and functions does not necessarily parallel those for vegetation. At the longest studied system (rapid vegetation recovery) the high marsh snail Melampus bidentatus took two decades to reach densities comparable with a nearby reference marsh, whereas the amphipod Orchestia grillus was well established on a slow-recovery marsh, reed grass dominated after 9 years. Typical fish species assemblages were found in restoration site creeks and ditches within 5 years. Gut contents of fish in ditches and on the high marsh suggest that use of restored marsh as foraging areas may require up to 15 years to reach equivalence with reference sites. Bird species that specialize in salt marshes require appropriate vegetation; on the oldest restoration site, breeding populations comparable with reference marshland had become established after 15 years. Use of restoration sites by birds considered marsh generalists was initially high and was still nearly twice that of reference areas even after 20 years. Herons, egrets, and migratory shorebirds used restoration areas extensively. These results support our prediction that returning tides will set degraded marshes on trajectories that can bring essentially full restoration of ecological functions. This can occur within two decades, although reduced tidal action can delay restoration of some functions. With this success, Connecticut's Department of Environmental Protection established a dedicated Wetland Restoration Unit. As of 1999 tides have been restored at 57 separate sites along the Connecticut coast. [source] Smoke, Mulch, and Seed Broadcasting Effects on Woodland Restoration in Western AustraliaRESTORATION ECOLOGY, Issue 2 2002Deanna P. Rokich Abstract Smoke, canopy-derived mulch, and broadcast seeds were used to maximize the establishment of Banksia woodland species in sand quarries in Western Australia. Smoke, particularly aerosol smoke, had a positive effect on total seedling recruitment. Pre-mined (woodland) sites showed a 42-fold increase in total germinants and a 3-fold increase in the number of species with aerosol smoke application. Post-mined (restored) sites showed only a 3.6-fold increase in total germinants and a 1.4-fold increase in the number of species. Two water-based smoke chemicals, DC10 (pH 4.5) and SC63 (pH 2.5), increased seedling recruitment at both sites but were not as effective in stimulating recruitment as aerosol smoke. Neither of the chemicals were effective in significantly increasing species richness. Application of aerosol smoke directly to seeds as a pretreatment before broadcasting had no effect on seedling recruitment. Broadcasting of seeds onto restoration sites significantly increased seedling abundance and richness. Application of a single layer of mulch from the canopy vegetation after seed broadcasting gave optimum seedling recruitment. Two layers of mulch significantly reduced recruitment, as did applying mulch before seed broadcasting. For broad-scale restoration, the application of smoke on newly restored sites would be more effectively achieved using smoke water sprayed over the soil surface. Species that do not recruit from replaced topsoil could be effectively recovered from broadcast seed rather than from mulch. [source] A Historical Perspective and Future Outlook on Landscape Scale Restoration in the Northwest Wisconsin Pine BarrensRESTORATION ECOLOGY, Issue 2 2000Volker C. Radeloff Abstract The concurrent discussions of landscape scale restoration among restoration ecologists, and of historic disturbance pattern as a guideline for forest management among forest scientists, offer a unique opportunity for collaboration between these traditionally separated fields. The objective of this study was to review the environmental history, early restoration projects, and current plans to restore landscape patterns at broader scales in the 450,000 ha northwest Wisconsin Pine Barrens. The Pine Barrens offer an example of a landscape shaped by fire in the past. In northwestern Wisconsin historically the barrens were a mosaic of open prairie, savanna, and pine forests on very poor, sandy soils. The surrounding region of better soils was otherwise heavily forested. Six restoration sites have been managed since the middle of this century using prescribed burns to maintain the open, barrens habitat. However, these sites are not extensive enough to mimic the shifting mosaic of large open patches previously created by fire. Extensive clear-cuts may be used as a substitute for these large fire patches so that presettlement landscape patterns are more closely approximated in the current landscape. We suggest that such silvicultural treatments can be suitable to restore certain aspects of presettlement landscapes, such as landscape pattern and open habitat for species such as grassland birds. We are aware that the effects of fire and clear-cuts differ in many aspects and additional management tools, such as prescribed burning after harvesting, may assist in further approximating the effect of natural disturbance. However, the restoration of landscape pattern using clear-cuts may provide an important context for smaller isolated restoration sites even without the subsequent application of fire, in this formerly more open landscape. [source] Restoring prairie pothole wetlands: does the species pool concept offer decision-making guidance for re-vegetation?APPLIED VEGETATION SCIENCE, Issue 2 2006Susan M. Galatowitsch Anon. (2004) Abstract Question: Do regional species pools, landscape isolation or on-site constraints cause plants from different guilds to vary in their ability to colonize restored wetlands? Location: Iowa, Minnesota, and South Dakota, USA. Methods: Floristic surveys of 41 restored wetlands were made three and 12 years after reflooding to determine changes in local species pools for eight plant guilds. The effect of landscape isolation on colonization efficiency was evaluated for each guild by plotting local species pools against distance to nearby natural wetlands, and the relative importance of dispersal vs. on-site constraints in limiting colonization was explored by comparing the local species pools of restored and natural wetlands within the region. Results: Of the 517 wetland plant taxa occurring in the region, 50% have established within 12 years. The proportion of the regional species pool represented in local species pools differed among guilds, with sedge-meadow perennials, emergent perennials and floating/submersed aquatics least represented (33-36%) and annual guilds most represented (74-94%). Colonization-to-extinction ratios suggest that floating/submersed aquatics have already reached a species equilibrium while sedge-meadow and emergent perennials are still accumulating species. Increasing distance to nearest wetlands decreased the proportion of the regional species pool present in local pools for all guilds except native annuals and woody plants. The maximum proportion predicted, assuming no distance constraint, was comparable to the lowest-diversity natural wetlands for most perennial guilds, and also lower than what was achieved in a planted, weeded restoration. Conclusions: A biotic constraints seem to limit the colonization of floating/submersed aquatics into natural or restored wetlands, whereas all other guilds are potentially constrained by dispersal or biotic factors (i.e. competition from invasive species). Using species pools to evaluate restoration progress revealed that immigration potential varies considerably among guilds, that local species richness does not necessarily correspond to immigration limitations, and that some guilds (e.g. sedge-meadow perennials) will likely benefit more than others from being planted at restoration sites. [source] | ||||||||||||||||