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Restoration Strategies (restoration + strategy)
Selected AbstractsIntegrating physiology and life history to improve fisheries management and conservationFISH AND FISHERIES, Issue 4 2006Jeffery L. Young Abstract Knowledge of life-history traits is increasingly recognized as an important criterion for effective management and conservation. Understanding the link between physiology and life history is an important component of this knowledge and in our view is particularly relevant to understanding marine and freshwater fishes. Such linkages (i.e. the life-history/physiology nexus) have been recently advocated for avian systems and here we explore this concept for fish. This paper highlights the gap in fisheries literature with regard to understanding the relationship between physiology and life history, and proposes ways in which this integration could improve fisheries management and conservation. We use three case studies on different fishes (i.e. the Pacific salmon, the grouper complex and tuna) to explore these issues. The physiological structure and function of fish plays a central role in determining stock response to exploitation and changes in the environment. Physiological measures can provide simple indicators necessary for cost-effective monitoring in the evaluation of fisheries sustainability. The declining state of world fisheries and the need to develop and implement restoration strategies, such as hatchery production or protected areas, provides strong incentive to better understand the influence of physiology on population and reproductive dynamics and early life history. Physiology influences key population-level processes, particularly those dealing with reproduction, which must be incorporated into the design and successful implementation of specific and broadscale initiatives (e.g. aquatic protected areas and bycatch reduction). Suggestions are made for how to encourage wider application of the physiology/life-history link, in fisheries management and conservation, as well as more broadly in education and research. [source] Plants intertwine fluvial landform dynamics with ecological succession and natural selection: a niche construction perspective for riparian systemsGLOBAL ECOLOGY, Issue 4 2009Dov Corenblit ABSTRACT Aim To contribute to the development of a macroevolutionary framework for riparian systems, reinforcing conceptual linkages between earth surface processes and biological and ecological processes. Location Riparian systems. Methods Literature review leading to an original proposition for perceiving the functioning of riparian systems in a new and different way. Results Riparian systems provide diverse landforms, habitats and resources for animals and plants. Certain organisms, defined as ,ecosystem engineers', significantly create and modify the physical components of riparian systems. Many studies have highlighted such engineering effects by animals on riparian systems, but the identification and understanding of the effects and responses of plants within fluvial corridors have emerged only recently. The modulation of matter, resources and energy flows by engineering plants helps establish characteristic sequences of fluvial landform creation and maintenance associated with synergetic ecological successions. We relate this process to the concept of niche construction, developed mainly by evolutionary biologists. Feedbacks between adaptive responses of riparian plants to flow regime and adjusting effects on biostabilization and bioconstruction are discussed in the context of niche construction at the scale of ecological succession and the evolution of organisms. Main conclusions Our conceptualization forges an integrated approach for understanding vegetated fluvial systems from a macroevolutionary perspective, for elucidating riparian ecosystem dynamics and potentially for establishing long-term stream conservation and restoration strategies. [source] Biology and ecology of amphidromous Gobiidae of the Indo-Pacific and the Caribbean regionsJOURNAL OF FISH BIOLOGY, Issue 4 2003P. Keith In the Indo-Pacific and the Caribbean regions, isolated rivers are host to amphidromous Gobiidae with a life cycle adapted to extreme climatic and hydrological seasonal variation. Although this is the most diverse family of freshwater fish, their biological cycle and the parameters and evolutionary processes that lead to such diversity are poorly understood. This paper reports on the current knowledge on reproduction (nidification, spawning, larval life and sexuality), recruitment into the rivers, upstream migration and distribution in the rivers. Management and restoration strategies to preserve amphidromous gobies, often endemic and bordering on extinction, require the development of research to have a better understanding of their life cycle. [source] Aromatic hydrocarbon degradation genes from chronically polluted Subantarctic marine sedimentsLETTERS IN APPLIED MICROBIOLOGY, Issue 5 2009M.S. Marcos Abstract Aim:, The goal of this study was to identify functional targets to detect polycyclic aromatic hydrocarbon (PAH)-degrading bacterial populations in cold marine ecosystems. Methods and Results:, We designed a degenerate primer set targeting genes encoding the , subunit of PAH-dioxygenases from Gram-positive bacteria. This primer set was used to amplify gene fragments from metagenomic DNA isolated from Subantarctic marine sediments (Ushuaia Bay, Argentina). These gene fragments were cloned and sequenced. We identified 14 distinct groups of genes, most of them showing significant relatedness with dioxygenases from Gram-positive bacteria of the genera Rhodococcus, Mycobacterium, Nocardioides, Terrabacter and Bacillus. The level of identity with these genes, however, was low to moderate (33,62% at the amino acid level). Conclusion:, These results indicate the presence of a high diversity of hitherto unidentified dioxygenase genes in this cold polluted environment. Significance and Impact of the Study:, Subantarctic marine ecosystems are particularly vulnerable to hydrocarbon pollution, and the development of environmental restoration strategies for these environments is pressing. The information obtained in this work will be the starting point for the design of quantitative molecular tools to analyse the abundance and dynamics of these aromatic hydrocarbon-degrading bacterial populations in the marine environment. [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] Tropical Montane Forest Restoration in Costa Rica: Overcoming Barriers to Dispersal and EstablishmentRESTORATION ECOLOGY, Issue 4 2000Karen D. Holl Abstract Tropical forests are being cleared at an alarming rate although our understanding of their ecology is limited. It is therefore essential to design restoration experiments that both further our basic knowledge of tropical ecology and inform management strategies to facilitate recovery of these ecosystems. Here we synthesize the results of research on tropical montane forest recovery in abandoned pasture in Costa Rica to address the following questions: (1) What factors limit tropical forest recovery in abandoned pasture? and (2) How can we use this information to design strategies to facilitate ecosystem recovery? Our results indicate that a number of factors impede tropical forest recovery in abandoned pasture land. The most important barriers are lack of dispersal of forest seeds and seedling competition with pasture grasses. High seed predation, low seed germination, lack of nutrients, high light intensity, and rabbit herbivory also affect recovery. Successful strategies to facilitate recovery in abandoned pastures must simultaneously overcome numerous obstacles. Our research shows that establishment of woody species, either native tree seedlings or early-successional shrubs, can be successful in facilitating recovery, by enhancing seed dispersal and shading out pasture grasses. On the contrary, bird perching structures alone are not an effective strategy, because they only serve to enhance seed dispersal but do not reduce grass cover. Remnant pasture trees can serve as foci of natural recovery and may enhance growth of planted seedlings. Our results highlight the importance of: (1) understanding the basic biology of an ecosystem to design effective restoration strategies; (2) comparing results across a range of sites to determine which restoration strategies are most generally useful; and (3) considering where best to allocate efforts in large-scale restoration projects. [source] The decline of metallophyte vegetation in floodplain grasslands: Implications for conservation and restorationAPPLIED VEGETATION SCIENCE, Issue 1 2009Esther C.H.E.T. Lucassen Abstract Question: Which biogeochemical processes are responsible for the decline of endemic metallophyte vegetation in floodplain grasslands? Location: Floodplain grasslands along the River Geul (the Netherlands) and metalliferous mine spoils near the River Geul (Belgium). Methods: In order to find factors and soil processes that have caused a decline of metallophytes and an increase of pseudo-metallophytes in floodplain grasslands, a soil study was done at locations currently and formerly dominated by metallophytes. In addition, changes in soil chemistry in recent decades in floodplain grasslands were investigated. Finally, a 2-year plant growth experiment was performed in the field, to test the effects of improving soil conditions by topsoil removal. Results: Metallophytes only occur on acidic floodplain soils (pH-H2O 5.0-5.5) with relatively high Zn availability (total Zn >40 ,mol g,1; Zn/Ca>0.8; Zn-H2O>59 ,mol kg,1) combined with low phosphate availability (Olsen-P,1250 ,mol kg,1). The Olsen-P and total Ca concentrations were relatively high in topsoil (0-20 cm), while total Zn was high throughout the soil profile (0-50 cm). Removal of topsoil led to recovery of P and Zn availability. Under the new soil conditions there was almost no growth and expansion of pseudo-metalliferous grasses in time, wheras metallophytes easily established, maintained and reproduced with significant increases in cover over time. Conclusions: On a global scale, metallophyte vegetation types are increasingly under threat of extinction. Our study shows that factors leading to higher soil alkalinity inhibit Zn availability at the expense of the metallophyte vegetation. Factors leading to a higher Olsen-P concentration stimulate the growth of more competitive pseudo-metallophyte grasses. Both eutrophication and alkalinisation have contributed to the decline of metallophyte vegetation in floodplains of the River Geul. Removal of the alkaline- and phosphate-enriched soil top layer restores the original soil chemistry and enables re-colonisation by the metallophyte vegetation. The results can be applied in conservation and restoration strategies for such sites. [source] Mechanotransduction of bovine articular cartilage superficial zone protein by transforming growth factor , signalingARTHRITIS & RHEUMATISM, Issue 11 2007Corey P. Neu Objective Mechanical signals are key determinants in tissue morphogenesis, maintenance, and restoration strategies in regenerative medicine, although molecular mechanisms of mechanotransduction remain to be elucidated. This study was undertaken to investigate the mechanotransduction process of expression of superficial zone protein (SZP), a critical joint lubricant. Methods Regional expression of SZP was first quantified in cartilage obtained from the femoral condyles of immature bovines, using immunoblotting, and visualized by immunohistochemistry. Contact pressure mapping in whole joints was accomplished using pressure-sensitive film and a load application system for joint testing. Friction measurements on cartilage plugs were acquired under boundary lubrication conditions using a pin-on-disk tribometer modified for reciprocating sliding. Direct mechanical stimulation by shear loading of articular cartilage explants was performed with and without inhibition of transforming growth factor , (TGF,) signaling, and SZP content in media was quantified by enzyme-linked immunosorbent assay. Results An unexpected pattern of SZP localization in knee cartilage was initially identified, with anterior regions exhibiting high levels of SZP expression. Regional SZP patterns were regulated by mechanical signals and correlated with tribological behavior. Direct relationships were demonstrated between high levels of SZP expression, maximum contact pressures, and low friction coefficients. Levels of SZP expression and accumulation were increased by applying shear stress, depending on location within the knee, and were decreased to control levels with the use of a specific inhibitor of TGF, receptor type I kinase and subsequent phospho-Smad2/3 activity. Conclusion These findings indicate a new role for TGF, signaling in the mechanism of cellular mechanotransduction that is especially significant for joint lubrication. [source] Community effects of invasive macrophyte control: role of invasive plant abundance and habitat complexityJOURNAL OF APPLIED ECOLOGY, Issue 2 2010Katya E. Kovalenko Summary 1. The control of invasive species has become a widespread management practice, yet information on the community effects of such efforts is very limited, there is no unified framework for monitoring their success and no guidelines exist to help minimize potential adverse impacts. 2. This study was conducted to determine how long-term efforts to control a widespread invasive macrophyte, Eurasian watermilfoil, affect native macrophytes, fish and macroinvertebrates. In addition, we examined how members of the aquatic fauna respond to changes in invasive macrophyte abundance and habitat complexity to understand the mechanisms underlying any potential community response. 3. Selective control of the invasive macrophyte had minor effects on habitat complexity due to timely recolonization by native macrophytes and it did not affect littoral fish richness and abundance. Macroinvertebrate communities were highly variable and some of that variation could be attributed to characteristics of the macrophyte community. Fish and macroinvertebrates were more affected by habitat complexity than by other attributes of the macrophyte assemblage. 4.Synthesis and applications. Management plans to control invasive species need to prioritize selective removal and timely restoration of the native assemblage. In this study, the invasive macrophyte was used by aquatic fauna, which emphasizes the need for immediate restoration of the native macrophyte community to mitigate for the lost habitat after invasive plant control efforts. As both fish and macroinvertebrates were more affected by complexity than other attributes of the macrophyte assemblage, re-establishment of habitat complexity appears to be a promising restoration strategy. On a more general note, we highlight the importance of assessing community response to the habitat provided by the invader and invader's function in the community when evaluating strategies to control invasive species. [source] A Raman spectroscopic and combined analytical approach to the restoration of severely damaged frescoes: the Palomino projectJOURNAL OF RAMAN SPECTROSCOPY, Issue 4 2008Howell G. M. Edwards Abstract The deterioration of art objects is normally relatively minor, controllable and attributable to environmental changes or bacterial invasion, and until now there has not been any recorded attempt to analyse an artwork that has been deliberately and significantly destroyed. The analytical problems are correspondingly larger but the potential reward from any information that can be forthcoming is thereby proportionately greater. The 17th Century Palomino frescoes on the vaulted ceiling of the Church of Sant Joan del Mercat in Valencia were largely destroyed by insurgents in the Spanish Civil War in 1936. The ensuing gunfire and a series of seven conflagrations inside the church had a devastating effect upon the artwork, and the surviving areas were also rendered unstable with respect to their detachment from the substrate. During the current restoration project being undertaken on these frescoes, an opportunity was provided for the application of several analytical techniques to secure information about the original pigment palette employed, the technology of application used by Palomino and the changes consequent upon the destruction process. Here, we report for the first time the use of analytical Raman spectroscopy, supported by scanning electron microscopy (SEM) and voltammetry of microparticles, for the combined identification of pigments, binders, substrate treatments and pigment alteration in an important, although badly damaged, wall painting for the informing of the ongoing conservation and restoration strategy. Copyright © 2008 John Wiley & Sons, Ltd. [source] Forest Regeneration in a Chronosequence of Tropical Abandoned Pastures: Implications for Restoration EcologyRESTORATION ECOLOGY, Issue 4 2000T. Mitchell Aide Abstract During the mid-1900s, most of the island of Puerto Rico was deforested, but a shift in the economy from agriculture to small industry beginning in the 1950s resulted in the abandonment of agricultural lands and recovery of secondary forest. This unique history provides an excellent opportunity to study secondary forest succession and suggest strategies for tropical forest restoration. To determine the pattern of secondary succession, we describe the woody vegetation in 71 abandoned pastures and forest sites in four regions of Puerto Rico. The density, basal area, aboveground biomass, and species richness of the secondary forest sites were similar to those of the old growth forest sites (>80 yr) after approximately 40 years. The dominant species that colonized recently abandoned pastures occurred over a broad elevational range and are widespread in the neotropics. The species richness of Puerto Rican secondary forests recovered rapidly, but the species composition was quite different in comparison with old growth forest sites, suggesting that enrichment planting will be necessary to restore the original composition. Exotic species were some of the most abundant species in the secondary forest, but their long-term impact depended on life history characteristics of each species. These data demonstrate that one restoration strategy for tropical forest in abandoned pastures is simply to protect the areas from fire, and allow natural regeneration to produce secondary forest. This strategy will be most effective if remnant forest (i.e., seed sources) still exist in the landscape and soils have not been highly degraded. Patterns of forest recovery also suggest strategies for accelerating natural recovery by planting a suite of generalist species that are common in recently abandoned pastures in Puerto Rico and throughout much of the neotropics. [source] Recovery of Bird Species in Minimally Restored Indonesian Tin Strip MinesRESTORATION ECOLOGY, Issue 2 2000Howard D. Passell Abstract Bird species richness and individual abundances were recorded in old, unrestored tin strip mine plots, in mined plots restored 1, 2, and 3 years before the study, and in adjacent, unmined, natural secondary forest plots on the 11,340-km2 Indonesian island of Bangka (2°S, 106°E). The objective was to assess the ecological recovery of unrestored and minimally restored mine plots compared with surrounding reference forest. Unrestored mines had not been mined or used for any other purpose for 14,30 years; plots in their first, second, and third year since restoration were old mines planted with Acacia mangium (Leguminosae) at a density of 400 trees/ha. Natural secondary forest plots 20 or more years since the last disturbance were immediately adjacent to both unrestored and restored plots. Bird surveys on 4-ha plots were performed during the 1995 breeding season. A comparison of data from unrestored plots of widely varying ages showed no significant differences among them for species richness, diversity (Shannon,Wiener index, H,), or individual abundance, indicating that little natural bird community recovery had occurred over time in the plots. However, increases did occur in restored sites over only 3 years for both species richness (r 2= 0.29, p = 0.04) and diversity (r 2= 0.45, p = 0.009). All values for third-year restored plots, however, were still significantly lower than corresponding values for adjacent natural secondary forest plots. The quick return of bird activity on the plots after minimal efforts at restoration supports the idea that simple, inexpensive restoration can be effective for "jump starting" degraded systems at large scales. Such a restoration strategy might be of particular value for degraded land in developing nations, where scientific, professional, and financial resources might be in short supply. Using this strategy, a small number of restoration professionals could mobilize the labor of many local people in many areas, serving to both improve ecological systems and to educate and engage local populations in restoration and conservation projects. [source] Strategic light manipulation as a restoration strategy to reduce alien grasses and encourage native regeneration in Hawaiian mesic forestsAPPLIED VEGETATION SCIENCE, Issue 3 2010S. McDaniel Abstract Question: Is there a light level at which alien grass biomass is reduced while still supporting growth and survival of native woody species, allowing for native species regeneration in abandoned pastures? Location: Island of Hawaii, USA. Methods: In a two-part study we examined the effect of light availability on common native woody and alien grass species found in secondary forests in Hawaii. A field survey was conducted to examine the relationship between light availability and canopy type (open pasture, planted canopy and secondary forest) on understory grass biomass and litter accumulation. We then experimentally manipulated light levels to determine the effect of light availability on growth and survival of six native woody species and three alien grasses. Low-light (5%), medium-light (10%) and high-light (20-30%) treatments were created using shade structures erected beneath the existing secondary koa canopy. Results: In the field survey, alien grass biomass was greatest under the open pasture and lowest in the secondary forest. There was a positive correlation between understory light availability and alien grass biomass. In the experimental study, large reductions in relative growth rates were documented for all of the grass species and four of the six woody species under the lowest light level. Although growth at 5% light is substantially reduced, survival is still high (84-100%), indicating that these species may persist under closed canopy. Conclusion: Low-light conditions result in the greatest reduction in alien grass biomass while creating an environment in which native woody species can grow and survive. [source] Fast, scalable, and distributed restoration in general mesh optical networksBELL LABS TECHNICAL JOURNAL, Issue 1 2001Gary P. Austin Service providers are demanding transport network solutions that can accommodate exponential traffic growth and, at the same time, provide novel services such as point-and-click provisioning of very high bandwidth circuits, optical bandwidth service management, fast protection and restoration, and bandwidth on demand. It is becoming increasingly clear that the required scalability (terabits/s to petabits/s) and cost structure can only be provided by transparent optical cross connects (OXCs). The challenge, then, is to make the optical network consisting of OXCs, dense wavelength division multiplexers (DWDMs), and optical add/drop multiplexers (OADMs) dynamic and intelligent. A major aspect of this intelligence is fast provisioning and restoration. In this paper, we present a fast, scalable, and distributed solution for optical layer restoration in general mesh-type optical networks, which is being implemented as part of the Optical Navigator System (ONS) residing in Lucent's LambdaRouter product. The key ingredients to our solution are a fast and scalable restoration strategy, a fast and scalable connection setup strategy, a contention-free wavelength assignment strategy, and a fast and reliable data communications network to exchange signaling messages. We also introduce novel concepts of demand bundling and optical virtual paths that ensure that restoration performance scales with network and traffic volumes. Together these components provide an intelligent optical networking solution that not only guarantees restoration times within few hundreds of milliseconds, but also achieves scalability. [source] | |||||||||||||