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Natural Recovery (natural + recovery)
Selected AbstractsWHY IS NATURAL RECOVERY SO COMMON FOR ADDICTIVE DISORDERS?ADDICTION, Issue 9 2010WENDY S. SLUTSKE No abstract is available for this article. [source] Continuities and changes in self-change researchADDICTION, Issue 9 2010Harald Klingemann ABSTRACT Aims A substantial literature demonstrates that natural recoveries from substance use disorders not only occur but are a common pathway to recovery. This article reviews selectively and comments on the current state-of-the-art in natural recovery research. Methods Basic concepts in natural recovery research are presented, and topical and methodological trends and changes in self-change research over time are discussed. Conclusions Although considerable progress has occurred in natural recovery research, several topics deserving of further research are identified, and implications for policy practice are discussed. [source] Effectiveness of very thin soil layers in chemical release from bed sedimentENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 2 2001Bryan Talbert The chemical containment effectiveness of both the natural recovery and the "particle broadcasting" processes for remediating contaminated bed-sediments depend upon very thin soil and/or sand layers millimeters in depth. Conventional capping for in situ chemical containment of bed-sediment or dredged material typically involves thick layers of 30 to 90 centimeters in depth. Few studies have been conducted with thin layers of candidate natural materials. A steady-state benzoic acid dissolution test apparatus and procedure, devised to realistically simulate bed-sediment chemo-dynamic conditions, was used to measure chemical flux through thin layers (1 to 8 mm) of soil, sand, and ideal porous media. The thin layers were found to be very effective. Flux reductions ranged from 81 to 96%, with fine sand being slightly better than top soil. Design algorithms developed for the thick layers used in conventional capping design will under predict the flux through very thin layers. Advective flow induced by surface roughness is proposed to explain the higher average measure d-to-predicted flux ratio of 1.67. [source] The role of monitored natural recovery in sediment remediationINTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT, Issue 1 2006Victor S Magar Abstract The long-term goal of monitored natural recovery (MNR) is to achieve ecological recovery of biological endpoints in order to protect human and ecological health. Insofar as ecological recovery is affected by surface-sediment-contaminant concentrations, the primary recovery processes for MNR are natural sediment burial and contaminant transformation and weathering to less toxic forms. This paper discusses the overall approach for effective implementation of MNR for contaminated sediment sites. Several lines of evidence that may be used to demonstrate natural recovery processes are summarized, including documentation of source control; evidence of contaminant burial; measurement of surface sediment mixing depths and the active sediment benthic layer; measurement of sediment stability; contaminant transformation and weathering; modeling sediment transport, contaminant transport, and ecological recovery; measuring ecological recovery and long-term risk reduction; knowledge of future plans for use and development of the site; and watershed and institutional controls. In general, some form of natural recovery is expected and should be included as part of a remedy at virtually all contaminated sediment sites. Further, MNR investigations and an understanding of natural recovery processes provide cost-effective information and support the evaluation of more aggressive remedies such as capping, dredging, and the use of novel amendments. The risk of dredging or capping may be greater than the risk of leaving sediments in place at sites where capping or dredging offer little long-term environmental gain but pose significant short-term risks for workers, local communities, and the environment. [source] Gastroprotective properties of Myristica malabarica against indometacin-induced stomach ulceration: a mechanistic explorationJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 11 2007Debashish Banerjee The healing activity of the methanol extract of the spice rampatri, Myristica malabarica, (RM) and omeprazole against indometacin-induced stomach ulceration has been studied in a mouse model. Treatment with RM (40 mg kg,1 per day) and omeprazole (3 mg kg,1 per day) for 3 days could effectively heal the stomach ulceration, as revealed from the ulcer indices and histopathological studies. Compared with the ulcerated group, treatment with RM and omeprazole for 3 days reduced the macroscopic damage score by approximately 72% and 76%, respectively (P < 0.001), establishing the efficacy of RM. The extent of ulcer healing offered by 3 days' treatment with RM or omeprazole was better than that observed with natural recovery over 5 and 7 days (P < 0.05). The healing capacities of RM and omeprazole could be attributed to their antioxidant activity as well as the ability to enhance the mucin content of the gastric tissues. Both drugs reduced lipid peroxidation (by 42,44%) and protein carbonyl content (by 34%), and augmented non-protein thiol levels beyond normal values. Furthermore, RM improved the mucin level beyond the normal value, while omeprazole restored it to near normalcy. [source] Comparison of two plant functional approaches to evaluate natural restoration along an old-field , deciduous forest chronosequenceJOURNAL OF VEGETATION SCIENCE, Issue 2 2009Isabelle Aubin Abstract Question: Are direct and indirect trait-based approaches similar in their usefulness to synthesize species responses to successional stages? Location: Northern hardwood forests, Québec, Canada (45°01,,45°08,N; 73°58,,74°21,W). Methods: Two different trait-based approaches were used to relate plant functional traits to succession on an old-field , deciduous forest chronosequence: (i) a frequently used approach based on co-occurrence of traits (emergent groups), and (ii) a new version of a direct functional approach at the trait level (the fourth-corner method). Additionally, we selected two different cut-off levels for the herb subset of the emergent group classification in order to test its robustness and ecological relevance. Results: Clear patterns of trait associations with stand developmental stages emerged from both the emergent group and the direct approach at the trait level. However, the emergent group classification was found to hide some trait-level differences such as a shift in seed size, light requirement and plant form along the chronosequence. Contrasting results were obtained for the seven or nine group classification of the herbaceous subset, illustrating how critical is the number of groups for emergent group classification. Conclusion: The simultaneous use of two different trait-based approaches provided a robust and comprehensive characterization of vegetation responses in the old-field , deciduous forest chronosequence. It also underlines the different goals as well as the limitations and benefits of these two approaches. Both approaches indicated that abandoned pastures of the northern hardwood biome have good potential for natural recovery. Conversion of these lands to other functions may lead to irremediable loss of biodiversity. [source] Settlement and Survival of the Oyster Crassostrea virginica on Created Oyster Reef Habitats in Chesapeake BayRESTORATION ECOLOGY, Issue 2 2007Janet A. Nestlerode Abstract Efforts to restore the Eastern oyster (Crassostrea virginica) reef habitats in Chesapeake Bay typically begin with the placement of hard substrata to form three-dimensional mounds on the seabed to serve as a base for oyster recruitment and growth. A shortage of oyster shell for creating large-scale reefs has led to widespread use of other materials such as Surf clamshell (Spisula solidissima), as a substitute for oyster shell. Oyster recruitment, survival, and growth were monitored on intertidal reefs constructed from oyster and Surf clamshell near Fisherman's Island, Virginia, U.S.A. and on a subtidal Surf clamshell reef in York River, Virginia, U.S.A. At the intertidal reefs, oyster larvae settlement occurred at similar levels on both substrate types throughout the monitoring period but higher levels of post-settlement mortality occurred on clamshell reefs. The oyster shell reef supported greater oyster growth and survival and offered the highest degree of structural complexity. On the subtidal clamshell reef, the quality of the substrate varied with reef elevation. Large shell fragments and intact valves were scattered around the reef base, whereas small, tightly packed shell fragments paved the crest and flank of the reef mound. Oysters were more abundant and larger at the base of this reef and less abundant and smaller on the reef crest. The availability of interstitial space and appropriate settlement surfaces is hypothesized to account for the observed differences in oyster abundance across the reef systems. Patterns observed emphasize the importance of appropriate substrate selection for restoration activities to enhance natural recovery where an underlying habitat structure is destroyed. [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] 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] | |||||||||||||