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Reclamation
Kinds of Reclamation Terms modified by Reclamation Selected AbstractsIMPACT OF COAL SURFACE MINING AND RECLAMATION ON SUSPENDED SEDIMENT IN THREE OHIO WATERSHEDS,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 4 2000James V. Bonta ABSTRACT: Prior to PL95,87 little research had been conducted to determine the impacts of mining and reclamation practices on sediment concentrations and yields on a watershed scale. Furthermore, it was unknown whether sediment yield and other variables would return to undisturbed levels after reclamation. Therefore, three small watersheds, with differing lithologies and soils, were monitored for runoff and suspended sediment concentrations during three phases of watershed disturbances: undisturbed watershed condition, mining and reclamation disturbances, and post-reclaimed condition. Profound increases in suspended-sediment concentrations, load rates, and yields due to mining and reclamation activities, and subsequent drastic decreases after reclamation were documented. Even with increases in runoff potential, reductions in suspended-sediment concentrations and load rates to below or near undisturbed-watershed levels is possible by using the mulch-crimping technique and by removing diversions. Maximum concentrations and load rates occurred during times of active disturbances that exposed loose soil and spoil to high-intensity rains. Sediment concentrations remained elevated compared with the undisturbed watershed when diversions were not well maintained and overtopped, and when they were not removed for final reclamation. Diversions are useful for vegetation establishment, but should be maintained until they are removed for final reclamation after good vegetative cover is established. [source] CMP wastewater management using the concepts of design for environmentENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 1 2002Gordon C. C. YangArticle first published online: 20 APR 200 Application of design for environment (DfE) concepts to management of wastewater from chemical mechanical polishing (CMP) processes are presented in this paper. Today, DfE is a prevailing concept and is widely adopted by advanced nations in lieu of the traditional "command and control" approach to control waste and toxic emissions. Designing environmentally-benign processes and products is a new and challenging frontier for engineering professionals, including those in the semiconductor industry. An insatiable need for water and subsequent wastewater treatment has imposed a chilling effect on semiconductor industry growth. It was estimated that semiconductor producers consumed more than 5.523 × 108 m3 of water in 2000. Of this amount, CMP processes accounted for 40% of the total. The CMP tool market and CMP slurry market are estimated to have 36% and 29% annual growth rates, respectively between 2000 and 2005. Inevitably, a tremendous amount of waste slurry and post-CMP rinse water will be generated and have to be managed properly. CMP wastewater is characterized by its high content of suspended solids having sub-micron particle sizes, high turbidity, and high conductivity. Traditional wastewater treatment technologies, such as chemical coagulation/precipitation, do not work well for CMP wastewater, because it would generate a large volume of sludge, which might cause disposal problems in many countries, such as Taiwan. Therefore, utilizing pollution prevention principles in the design of CMP tools, development of new CMP slurries, and improved plant operations are necessary to minimize environmental damage. Reclamation of process water is also a common requirement in the semiconductor industry. To this end, several alternatives for source reduction of CMP wastewater and water reclamation are presented in this paper. [source] Analytical Studies on the Impact of Land Reclamation on Ground Water FlowGROUND WATER, Issue 6 2001Jiu J. Jiao Land reclamation has been a common practice to produce valuable land in coastal areas. The impact of land reclamation on coastal environment and marine ecology is well recognized and widely studied. It has not been recognized yet that reclamation may change the regional ground water regime, which may in turn modify the coastal environment, flooding pattern, and stability of slopes and foundations. This paper represents the first attempt to examine quantitatively the effect of reclamation on ground water levels. Analytical solutions are developed to study the ground water change in response to reclamation based on two hypothetical models. In the first model, the ground water flow regime changes only in the hillside around the reclamation areas. In the second model, the ground water regime changes in the entire hill. Both models assume that the ground water flow is in a steady state and satisfies the Dupuit assumptions. Hypothetical examples are used to demonstrate how the ground water level, ground water divide and ground water submarine discharge will change with the scale and hydraulic conductivity of the reclamation materials. The results show that the change of ground water regime depends mainly on the length of the reclaimed area and the values of hydraulic conductivity of the reclaimed materials. It is also seen that the reclamation may impact not only the ground water regime near the coast areas around the reclamation site, but also that in the coast areas opposite the reclamation area. A reclamation site near Tseung Kwan O in the New Territories in Hong Kong, China, is used as a case study to discuss the possible modification of the ground water system caused by reclamation. [source] 18th- and 19th-century shipyards at the south-east entrance to the West India Docks, LondonINTERNATIONAL JOURNAL OF NAUTICAL ARCHAEOLOGY, Issue 2 2003Ken Pitt Archaeological fieldwork in 1997 on the Isle of Dogs, at the south-east entrance to the West India Docks, recovered evidence of 17th- to 19th-century shipyards, associated activities and foreign trade. Reused timbers may be the remains of the 17th-century Rolt's yard. Reclamation along the natural inlet was accompanied by the construction of a timber dry dock probably in the late 18th century. This soon fell out of use and was filled in with the construction of new dry docks to the south in 1806 by Thomas Pitcher. Much of the debris dating to the first half of the 19th century from ship repairing and building and from a range of ancillary crafts, together with ceramics from Iberia and the Far East, probably came from Pitcher's yard. [source] Adaptive restoration of sand-mined areas for biological conservationJOURNAL OF APPLIED ECOLOGY, Issue 1 2005JASON CUMMINGS Summary 1Adaptive management approaches to ecological restoration are current best practice. The usefulness of such an approach was tested in this study by implementing repeated experiments that examined restoration options for derelict sand mine sites dominated by Imperata cylindrica. Reclamation of degraded land that is dominated by I. cylindrica is a common problem throughout the tropics. 2Initially, the hypothesized barrier to regeneration was limited seedling establishment because of I. cylindrica competition. After burning the grassland, woody weed control and planting of seedlings were implemented in factorial combination. 3Seedling survival 28 months after planting averaged 26%, with < 1% of all seedlings establishing to a height > 1 m. The hypothesis that a transition barrier comprising solely biotic interactions restricted regeneration of native woody cover was rejected after seedlings and natural regeneration failed to thrive in this experiment. 4A revised hypothesis, that the transition barrier comprised a combination of abiotic limitations (soil deficiencies) and biotic interactions (Wallabia bicolor browsing and I. cylindrica competition), was developed. A second experiment tested this hypothesis by removing W. bicolor (fencing), slashing the I. cylindrica, adding organic mulch and planting a mixture of native pioneer and secondary successional woody species in factorial combination. 5Seedling survival was 61% in the second experiment and mulching significantly enhanced the survival and growth of all planted species. Planting alone reduced the regeneration of I. cylindrica after slashing. Native woody cover establishment was maximized by planting seedlings in mulched treatments. 6Synthesis and applications. Taken together, these experiments support the hypothesis that there is a barrier restricting regeneration of native woody cover, and the barrier probably comprises both abiotic and biotic components. By adopting an adaptive management approach to the ecological restoration of sites, significant insights into their management requirements have been gained, supporting the current best practice restoration framework. Insights gained through monitoring and adaptation will be used to update the reserve plan of management, enhancing restoration of this severely degraded area and promoting connectivity of native woody cover within the conservation estate. [source] Spatial variability of total soil carbon and nitrogen stocks for some reclaimed minesoils of southeastern Ohio,LAND DEGRADATION AND DEVELOPMENT, Issue 3 2008G. Nyamadzawo Abstract Reclamation of drastically disturbed minesoils and subsequent planting of trees and/or grasses can result in a rapid build-up of carbon (C) in the soil. However, the amount of C sequestered in reclaimed minesoils may vary with the amount of time since reclamation. In this study, we assessed total carbon (TC) and total nitrogen (TN) concentrations for reclaimed minesoils located in northeastern Ohio and characterized by distinct reclamation age chronosequences. Reclaimed minesoils studied were R78G, reclaimed in 1978 and immediately seeded to grass; R82GT, reclaimed in 1982 and immediately seeded to grass and trees were planted 5 years later; and R87G, reclaimed in 1987 and immediately seeded to grass. An unmined site, UMG, was also included as a reference. Our objectives were to evaluate the variability with respect to mean and the spatial variability of pH, bulk density (,b), TC and TN concentrations, and stocks in each reclaimed minesoil. Thirty soil samples were collected at each of the 0,15, 15,30, and 30,50,cm depth. The coefficient of variation (CV) for ,b was least, <15 per cent at each site and depth. For TN concentration and stock, CV was moderate, 15,35 per cent, in each field except the UMG where it was high, >35 per cent at 0,15, and 15,30,cm depths. For TC concentration and stocks, CV was high, >35 per cent, across all minesoils and generally increased with depth. The C/N ratio followed the same tend as TC and TN stocks and ranged from 40 per cent to 123 per cent across minesoils. Geostatistical analysis also showed an increase in sample variance with increasing amount of time since reclamation for most soil properties under investigation. Sample variance for TC concentration and stocks also increased with depth in reclaimed minesoils. However, no definite relationship emerged between amount of time since reclamation and the spatial dependence of TC and TN concentrations and stocks. Overall this study showed that reclamation of drastically disturbed minesoils increased the soil C concentration and stocks and reclamation by initially seeding to grasses followed by planting trees was the best management option for speedy accretion of soil C and soil quality enhancement. Copyright © 2007 John Wiley & Sons, Ltd. [source] Naturally Saline Boreal Communities as Models for Reclamation of Saline Oil Sand TailingsRESTORATION ECOLOGY, Issue 4 2005Brett G. Purdy Abstract Reclaimed landscapes after oil sands mining have saline soils; yet, they are required to have similar biodiversity and productivity as the predisturbance nonsaline landscape. Given that many species in the boreal forest are not tolerant of salinity, we studied the effects of soil salinity on plant communities in natural saline landscapes to understand potential plant responses during the reclamation process. Vegetation,soil relationships were measured along transects from flooded wetlands to upland forest vegetation in strongly saline, slightly saline, nonsaline, and reclaimed boreal landscapes. In strongly saline landscapes, surface soil salinity was high (>10 dS/m) in flooded, wet-meadow, and dry-meadow vegetation zones as compared to slightly saline (<5 dS/m) and nonsaline (<2 dS/m) landscapes. Plant communities in these vegetation zones were quite different from nonsaline boreal landscapes and were dominated by halophytes common to saline habitats of the Great Plains. In the shrub and forest vegetation zones, surface soil salinity was similar between saline and nonsaline landscapes, resulting in similar plant communities. In strongly saline landscapes, soils remained saline at depth through the shrub and forest vegetation zones (>10 dS/m), suggesting that forest vegetation can establish over saline soils as long as the salts are below the rooting zone. The reclaimed landscape was intermediate between slightly saline and nonsaline landscapes in terms of soil salinity but more similar to nonsaline habitats with respect to species composition. Results from this study suggest it may be unrealistic to expect that plant communities similar to those found on the predisturbance landscape can be established on all reclaimed landscapes after oil sands mining. [source] Examining the Politics of Reclamation: The 1944 Acreage Limitation Debate in CongressTHE HISTORIAN, Issue 2 2005Kathleen B. Freeland First page of article [source] A Stitch in Time: Third-Wave Feminist Reclamation of Needled ImageryTHE JOURNAL OF POPULAR CULTURE, Issue 4 2010RICIA A. CHANSKY First page of article [source] Slag, steel and swamp: Perceptions of restoration of an urban coastal saltmarshECOLOGICAL MANAGEMENT & RESTORATION, Issue 2 2005Nicholas Gill A community group, in conjunction with local government and industry, has been working on aquatic and terrestrial restoration at a Wollongong saltmarsh, previously diminished in size and degraded by harbour reclamation and an urban rubbish tip. Students evaluate restoration progress to date and devise some interesting potential directions. [source] Role of geometrical dimensions in electrophoresis applications with orthogonal fieldsELECTROPHORESIS, Issue 15 2005Mario A. Oyanader Abstract The role of geometrical dimensions in electrophoresis applications with axial and orthogonal (secondary) electric fields is investigated using a rectangular capillary channel. In particular, the role of the applied orthogonal electrical field in controlling key parameters involved in the effective diffusivity and effective (axial) velocity of the solute is identified. Such mathematically friendly relationships are obtained by applying the method of spatial averaging to the solute species continuity equation; this is accomplished after the role of the capillary geometrical dimensions on the applied electrical field equations has been studied. Moreover, explicit analytical expressions are derived for the effective parameters, i.e., diffusivity and convective velocity as functions of the applied (orthogonal) electric field. Previous attempts (see Sauer et al., 1995) have only led to equations for these parameters that require numerical solution and, therefore, limited the use of such results to practical applications. These may include, for example, the design of separation processes as well as environmental applications such as soil reclamation and wastewater treatment. An illustration of how a secondary electrical field can aid in reducing the optimal separation time is included. [source] CMP wastewater management using the concepts of design for environmentENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 1 2002Gordon C. C. YangArticle first published online: 20 APR 200 Application of design for environment (DfE) concepts to management of wastewater from chemical mechanical polishing (CMP) processes are presented in this paper. Today, DfE is a prevailing concept and is widely adopted by advanced nations in lieu of the traditional "command and control" approach to control waste and toxic emissions. Designing environmentally-benign processes and products is a new and challenging frontier for engineering professionals, including those in the semiconductor industry. An insatiable need for water and subsequent wastewater treatment has imposed a chilling effect on semiconductor industry growth. It was estimated that semiconductor producers consumed more than 5.523 × 108 m3 of water in 2000. Of this amount, CMP processes accounted for 40% of the total. The CMP tool market and CMP slurry market are estimated to have 36% and 29% annual growth rates, respectively between 2000 and 2005. Inevitably, a tremendous amount of waste slurry and post-CMP rinse water will be generated and have to be managed properly. CMP wastewater is characterized by its high content of suspended solids having sub-micron particle sizes, high turbidity, and high conductivity. Traditional wastewater treatment technologies, such as chemical coagulation/precipitation, do not work well for CMP wastewater, because it would generate a large volume of sludge, which might cause disposal problems in many countries, such as Taiwan. Therefore, utilizing pollution prevention principles in the design of CMP tools, development of new CMP slurries, and improved plant operations are necessary to minimize environmental damage. Reclamation of process water is also a common requirement in the semiconductor industry. To this end, several alternatives for source reduction of CMP wastewater and water reclamation are presented in this paper. [source] Analytical Studies on the Impact of Land Reclamation on Ground Water FlowGROUND WATER, Issue 6 2001Jiu J. Jiao Land reclamation has been a common practice to produce valuable land in coastal areas. The impact of land reclamation on coastal environment and marine ecology is well recognized and widely studied. It has not been recognized yet that reclamation may change the regional ground water regime, which may in turn modify the coastal environment, flooding pattern, and stability of slopes and foundations. This paper represents the first attempt to examine quantitatively the effect of reclamation on ground water levels. Analytical solutions are developed to study the ground water change in response to reclamation based on two hypothetical models. In the first model, the ground water flow regime changes only in the hillside around the reclamation areas. In the second model, the ground water regime changes in the entire hill. Both models assume that the ground water flow is in a steady state and satisfies the Dupuit assumptions. Hypothetical examples are used to demonstrate how the ground water level, ground water divide and ground water submarine discharge will change with the scale and hydraulic conductivity of the reclamation materials. The results show that the change of ground water regime depends mainly on the length of the reclaimed area and the values of hydraulic conductivity of the reclaimed materials. It is also seen that the reclamation may impact not only the ground water regime near the coast areas around the reclamation site, but also that in the coast areas opposite the reclamation area. A reclamation site near Tseung Kwan O in the New Territories in Hong Kong, China, is used as a case study to discuss the possible modification of the ground water system caused by reclamation. [source] Comparison of stormflow responses of surface-mined and forested watersheds in the Appalachian Mountains, USAHYDROLOGICAL PROCESSES, Issue 16 2006Timothy L. Negley Abstract The results of a hydrological analysis that was conducted as part of a larger, multifaceted, collaborative effort to quantify ecosystem functions in watersheds subjected to land-use and land-cover change are presented. The primary goal of the study was to determine whether a small watershed in the Appalachian region (USA) that was recently subjected to surface mining and reclamation practices produces stormflow responses to rain events that are different from those produced by a nearby reference watershed covered by young, second-growth forest. Water balances indicated that runoff yields did not vary significantly between the two watersheds on an annual basis. Statistically significant differences (p,0·05) in runoff responses were observed on an event basis, however, with the mined/reclaimed watershed producing, on average (a) higher storm runoff coefficients (2·5×), (b) greater total storm runoff (3×), and (c) higher peak hourly runoff rates (2×) when compared with the reference watershed. Results of a unit hydrograph analysis also showed, unexpectedly, that the modelled unit responses of the two watersheds to effective rainfall pulses were similar, despite the noted differences in land cover. Differences in stormflow responses were thus largely explained by dramatic reductions in cumulative rates of rainfall abstraction (measured using infiltrometers) attributable to soil compaction during land reclamation. Additional field hydrological measurements on other mined watersheds will be needed to generalize our results, as well as to understand and predict the cumulative hydrological impacts of widespread surface mining in larger watersheds and river basins. Copyright © 2006 John Wiley & Sons, Ltd. [source] Runoff generation and routing on artificial slopes in a Mediterranean,continental environment: the Teruel coalfield, SpainHYDROLOGICAL PROCESSES, Issue 3 2002José-Manuel Nicolau Abstract The aim of this study was to identify the mechanisms of runoff generation and routing and their controlling factors at the hillslope scale, on artificial slopes derived from surface coal mining reclamation in a Mediterranean,continental area. Rainfall and runoff at interrill and microcatchment scales were recorded for a year on two slopes with different substrata: topsoil cover and overburden cover. Runoff coefficient and runoff routing from interrill areas to microcatchment outlets were higher in the overburden substratum than in topsoil, and greater in the most developed rill network. Rainfall volume is the major parameter responsible for runoff response on overburden, suggesting that this substratum is very impermeable,at least during the main rainfall periods of the year (late spring and autumn) when the soil surface is sealed. In such conditions, most rainfall input is converted into runoff, regardless of its intensity. Results from artificial rainfall experiments, conducted 3 and 7 years after seeding, confirm the low infiltration capacity of overburden when sealed. The hydrological response shows great seasonal variability on the overburden slope in accordance with soil surface changes over the year. Rainfall volume and intensities (I30, I60) explain runoff at the interrill scale on the topsoil slope, where rainfall experiments demonstrated a typical Hortonian infiltration curve. However, no correlation was found at the microcatchment level, probably because of the loss of functionality of the only rill as ecological succession proceeded. The runoff generation mechanism on the topsoil slope is more homogeneous throughout the year. Runoff connectivity, defined as the ratio between runoff rates recorded at the rill network scale and those recorded at the interrill area scale in every rainfall event, was also greater on the rilled overburden slope, and in the most developed rill network. The dense rill networks of the overburden slope guarantee very effective runoff drainage, regardless of rainfall magnitude. Rills drain overland flow from interrill-sealed areas, reducing the opportunity of reinfiltration in areas not affected by siltation. Runoff generation and routing on topsoil slopes are controlled by grass cover and soil moisture content, whereas on overburden slopes rill network density and soil moisture content are the main controlling factors. Copyright © 2002 John Wiley & Sons, Ltd. [source] The lignite electricity-generating sector in Greece: Current status and future prospectsINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 9 2004N. Koukouzas Abstract Lignite plays an important role in Greece's energy sector as it satisfies over 70% of country's needs in electric power. The extraction of lignite takes place mainly in three regions of Greece, namely Ptolemais-Amyndeon, Megalopolis and Florina. The annual production of lignite is around 60 million tons, out of which 48 million tons derive from the coal fields of northern Greece (Ptolemais-Amyndeon and Florina). Almost the entire lignite production is consumed for electricity generation, while small amounts of lignite are used for briquettes and other applications. The Greek coal-fired power plants, which are about 4500 MW, use conventional technology and they are old (an average of 30 years). In the coming years new coal fields will be exploited in Florina,another 2.5 million tons of coal,in order to satisfy the currently under construction 365 MW plant located at Meliti, Florina, Northern Greece. Even though the lignite reserves are widespread in Greece and other areas such as Elassona and Drama could possibly host power plants, it is expected that the Florina power plant will be the last coal-fired plant to be build in the country. Lignite has to compete with natural gas,the construction of the main gas pipeline network has been completed,imported oil and renewable energy sources. The new EU regulations on power plant emissions raise obstacles for the firing of lignite, although it is low in sulphur. It must be shown that lignite produces low cost electricity in a environmentally friendly manner. The utilization of fly ash and land reclamation can improve the situation in lignite mining. In particular, specific attention was paid to further research and potential use of fly ash in road construction, the production of bricks and concrete, and the production of zeolites from lignitic fly ash. The use of clean coal technologies in power plants can solve many emission problems. Specific measures to increase the efficiency of lignite-fired power units might include: identification of the loss sources of every unit, improvement of the cold end of the steam turbines, optimization of the beater wheel mills operation, and the combination of natural gas-fired turbines with the existing boilers. The liberalization of the electricity market needs to be considered seriously from the lignite industry, since the potential electricity producers can freely choose from all kinds of fuels, such as imported coal, oil, gas and renewables. However, Greek lignite meets the requirements for the security of supply, as indicated in the EU's Green Paper. It needs only to be competitive in the new energy sector by improving mining and combustion conditions. Further research on these topics, through the European Commission's ECSC and Framework Programmes, as well as the national programmes, is required. Copyright © 2004 John Wiley & Sons, Ltd. [source] Global City Frontiers: Singapore's Hinterland and the Contested Socio-political Geographies of Bintan, IndonesiaINTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, Issue 1 2006TIM BUNNELL During the 1980s, Singapore's policy-makers perceived that the continued expansion of the Singapore economy required more spaces and workers beyond the 680-square-kilometre territorial limits of the city-state. While planning to extend these limits through further land reclamation, Singapore also began to foster economic cooperation with regional neighbours, most famously in the form of a so-called Growth Triangle incorporating proximate areas of Malaysia and Indonesia. The empirical focus of this article is on the tourist enclave developed on the Indonesian island of Bintan, a 45-minute ferry ride from Singapore. This enclave embodies complex re-territorializations. We specify how, despite a decade of re-fashioning zones of Bintan into quasi-enclaves and the literal and metaphorical cultivation of a tourist haven, other claims on these transfrontier zones resurfaced in the form of resistances and struggles over the terms of access to land and resources. It is argued that the trajectory of Bintan is symptomatic of wider transformations and epitomizes new configurations of sovereignty, urbanity and ,gated globalism'. [source] Spontaneous succession in limestone quarries as an effective restoration tool for endangered arthropods and plantsJOURNAL OF APPLIED ECOLOGY, Issue 1 2010Robert Tropek Summary 1. The view of post-mining sites is rapidly changing among ecologists and conservationists, as sensitive restoration using spontaneous succession may turn such sites into biodiversity refuges in human-exploited regions. However, technical reclamation, consisting of covering the sites by topsoil, sowing fast-growing herb mixtures and planting trees, is still commonly adopted. Until now, no multi-taxa study has compared technically reclaimed sites and sites left with spontaneous succession. 2. We sampled communities of vascular plants and 10 arthropod groups in technically reclaimed and spontaneously restored plots in limestone quarries in the Bohemian Karst, Czech Republic. For comparison, we used paired t -tests and multivariate methods, emphasizing red-list status and habitat specialization of individual species. 3. We recorded 692 species of target taxa, with a high proportion of red-listed (10%) and xeric specialist (14%) species, corroborating the great conservation potential of the quarries. 4. Spontaneously restored post-mining sites did not differ in species richness from the technical reclaimed sites but they supported more rare species. The microhabitat cover of leaf litter, herbs and moss, were all directly influenced by the addition of topsoil during reclamation. 5.Synthesis and applications. Our results show that the high conservation potential of limestone quarries could be realized by allowing succession to progress spontaneously with minimal intervention. Given the threat to semi-natural sparsely vegetated habitats in many regions, active restoration measures at post-mining sites should be limited to maintenance of early successional stages, instead of acceleration of succession. [source] Preparation of rubber composites from ground tire rubber reinforced with waste-tire fiber through mechanical millingJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2007Xin-Xing Zhang Abstract Composites made from ground tire rubber (GTR) and waste fiber produced in tire reclamation were prepared by mechanical milling. The effects of the fiber content, pan milling, and fiber orientation on the mechanical properties of the composites were investigated. The results showed that the stress-induced mechanochemical devulcanization of waste rubber and the reinforcement of devulcanized waste rubber with waste-tire fibers could be achieved through comilling. For a comilled system, the tensile strength and elongation at break of revulcanized GTR/fiber composites reached maximum values of 9.6 MPa and 215.9%, respectively, with 5 wt % fiber. Compared with those of a composite prepared in a conventional mixing manner, the mechanical properties were greatly improved by comilling. Oxygen-containing groups on the surface of GTR particles, which were produced during pan milling, increased interfacial interactions between GTR and waste fibers. The fiber-filled composites showed anisotropy in the stress,strain properties because of preferential orientation of the short fibers along the roll-milling direction (longitudinal), and the adhesion between the fiber and rubber matrix was improved by the comilling of the fiber with waste rubber. The proposed process provides an economical and ecologically sound method for tire-rubber recycling. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 4087,4094, 2007 [source] Removing pharmaceuticals and endocrine-disrupting compounds from wastewater by photocatalysisJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 2 2007Omatoyo K Dalrymple Abstract Widespread concerns continue to be raised about the increasing presence of emerging contaminants in the environment. Such compounds include a wide range of persistent organic chemicals, including pharmaceuticals and endocrine-disrupting compounds whose effects are poorly known, often because they have only begun to enter the environment and are showing up in wastewater treatment plants. The occurrence and behavior of these compounds in wastewater are key issues with regard to water reclamation and reuse. Treatment plants are now faced with the challenge of removing the compounds from their effluent before they enter natural waterways. In this regard, photocatalysis is a promising technology for wastewater treatment that offers many advantages over conventional and some advanced treatment options. The application of photocatalysis for the removal of pharmaceuticals and endocrine-disrupting compounds for wastewater is comprehensively surveyed in this paper. This treatment technology is not intended to replace conventional systems but to supplement for higher-quality effluent. The assessment places emphasis on the process fundamentals, advantages, and disadvantages of the technology. It also focuses on the current limitations and future research needs. Copyright © 2007 Society of Chemical Industry [source] NGOs, gender and indigenous grassroots developmentJOURNAL OF INTERNATIONAL DEVELOPMENT, Issue 6 2002Janet Henshall Momsen This paper looks at two very similar efforts by indigenous communities to develop a tourist attraction based on their own culture and to market it in two very different environments: California and Mexico. Both groups have been displaced from their traditional areas, are being advised by a woman consultant and are expecting women community members to provide cultural performances and crafts for sale to visitors. Unlike the NGOs involved, the communities see this tourism activity as a reclamation and reaffirmation of a culture that has been almost lost, rather than as an exercise in local economic development. Copyright © 2002 John Wiley & Sons, Ltd. [source] Cultivation of flax in spoil-bank clay: Mycorrhizal inoculation vs. high organic amendmentsJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 6 2008David Püschel Abstract A greenhouse experiment was focused on the application of arbuscular mycorrhizal fungi (AMF) in effective crop production during reclamation of coal-mine spoil banks. The aim of the study was to find out whether mycorrhizal inoculation improves growth of flax (Linum usitatissimum L.) and whether it can compensate for high doses of expensive organic amendment. Flax was planted in original spoil-bank gray Miocene clay amended with organic matter used for spoil-bank reclamation (mixture of composted urban waste and lignocellulose papermill waste). This amendment was applied in four descending doses equivalent to the application of 500, 200, 100, and 0 t ha,1. The plants received either a mixed inoculum of three AMF species (Glomus mosseae, G. claroideum, and G. intraradices) or were left uninoculated. Growth of flax was significantly increased by mycorrhizal inoculation in pure clay (by 60%) as well as in clay with all amendment doses (by 119% on average). Also, the addition of organic matter increased plant growth but, interestingly, the biomass production was comparable regardless the dose of amendment. Our results suggest that similar yields are attainable with only one fifth of the usual fertilization dose, which can significantly decrease costs related to the reclamation of spoil banks. If mycorrhizal inoculation is applied together with the optimized fertilization, growth of flax planted in spoil-bank clay can be further improved. [source] IMPACT OF COAL SURFACE MINING AND RECLAMATION ON SUSPENDED SEDIMENT IN THREE OHIO WATERSHEDS,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 4 2000James V. Bonta ABSTRACT: Prior to PL95,87 little research had been conducted to determine the impacts of mining and reclamation practices on sediment concentrations and yields on a watershed scale. Furthermore, it was unknown whether sediment yield and other variables would return to undisturbed levels after reclamation. Therefore, three small watersheds, with differing lithologies and soils, were monitored for runoff and suspended sediment concentrations during three phases of watershed disturbances: undisturbed watershed condition, mining and reclamation disturbances, and post-reclaimed condition. Profound increases in suspended-sediment concentrations, load rates, and yields due to mining and reclamation activities, and subsequent drastic decreases after reclamation were documented. Even with increases in runoff potential, reductions in suspended-sediment concentrations and load rates to below or near undisturbed-watershed levels is possible by using the mulch-crimping technique and by removing diversions. Maximum concentrations and load rates occurred during times of active disturbances that exposed loose soil and spoil to high-intensity rains. Sediment concentrations remained elevated compared with the undisturbed watershed when diversions were not well maintained and overtopped, and when they were not removed for final reclamation. Diversions are useful for vegetation establishment, but should be maintained until they are removed for final reclamation after good vegetative cover is established. [source] Salinity-related desertification and management strategies: Indian experienceLAND DEGRADATION AND DEVELOPMENT, Issue 4 2009G. Singh Abstract High concentration of salts in the rootzone soil limits the productivity of nearly 953 million ha of productive land in the world. Australia, followed by Asia, has the largest area under salinity and sodicity. Most of the salt-affected soils and brackish ground water resources are confined to arid and semiarid regions and are the causative factors for triggering the process of desertification. The problem of salinity and sodicity has degraded about 6·73 million ha area in India. Secondary salinization associated with introduction of irrigation in dry areas like Thar desert in the western part of the country and Sharda Sahayak in Central India have caused desertification due to rise of salts with the rise in ground water level. Large scale cultivation of prawns using sea water in coastal Andhra Pradesh and elsewhere rendered about 2.1 million ha area unfit for agriculture. Similarly, 30,84 per cent ground water in north-western states of the country is either saline and /or brackish and is unfit for irrigation. Use of marginal quality water for irrigation has rendered several thousand ha of productive land unfit for cultivation. The Central Soil Salinity Research Institute was established in 1969 at Karnal to develop sustainable and eco-friendly technologies for reclamation and management of salt-affected soils and judicious use of marginal quality waters. The institute has developed location-specific techniques for reversion of salinity related desertification in India. Salient findings of research during the last three decades and more are presented in this review. This paper deals with (a) classification, nature and extent of salt-affected soils and poor quality water in India, (b) case studies/socio-economic concerns of salinity related desertification, (c) chemical, hydrological and biological approaches in use for rehabilitation of salt-affected soils, (d) guidelines for safe and productive use of marginal quality ground water through cyclic and mixed mode and precision irrigation techniques, (e) successful rehabilitation case studies, (f) alternate land use practices such as raising forest plantations, horticulture, agroforestry, high value medicinal, aromatic and flowering crops, etc., (g) technological, social, economic and environmental impacts and (h) future line of research. Issues requiring policy initiatives to halt salinity-related desertification are also discussed in this review paper. Copyright © 2009 John Wiley & Sons, Ltd. [source] Phytogenic resources of halophytes of Central Asia and their role for rehabilitation of sandy desert degraded rangelandsLAND DEGRADATION AND DEVELOPMENT, Issue 4 2009K. N. Toderich Abstract Based on soil characteristics, watertable level, mineral composition of plant biomass, morphological/reproductive traits and carbon discrimination values, a new concept for the classification of halophytes was developed. Six main groups of halophytes have been described within the desert flora of Central Asia. Significant changes on chemical contents of ions: Cl,, SO, HCO, Na+, K+, Ca2+ and Mg2+among 23 studied halophytic forage species were revealed. Alhagi pseudoalhagi, Poaceae spp., Artemisia diffusa containing minimum concentration of mineral ions were categorised as relatively more palatable and valuable feed for livestock on open grazing and as hay. Fresh biomass of forage species growing under highly saline soils sharply decreased with increasing of salinity gradient. Potassium concentration was found highest in Kochia scoparia, Agropyron desertorum, closely followed by Atriplex nitens, Suaeda salsa, while annuals Salsola spp., Bromus tectorum, Aeluropus littoralis, Tamarix hispida, Eremopyrum orientale, Agropyron desertorum contain low amount of mineral ions because excess of salts are exuded through salt glands present abundantly on the surface of the epidermis. Native and exotic, both C3 and C4, halophytes are suitable for reclamation of degraded lands have been proven very useful in demonstration trials. The fresh biomass of investigated C3 plants sharply decreased with the increasing of soil salinity gradient. An integrated Biosaline Agriculture model for sustainable and integrated use of marginal mineralised water resources and salt-affected soils through involvement of food,feed salt/drought tolerant crops and forage legumes to improve food security, alleviate poverty and enhance ecosystem health in smallholder crop,livestock systems has been demonstrated. Copyright © 2009 John Wiley & Sons, Ltd. [source] Spatial variability of total soil carbon and nitrogen stocks for some reclaimed minesoils of southeastern Ohio,LAND DEGRADATION AND DEVELOPMENT, Issue 3 2008G. Nyamadzawo Abstract Reclamation of drastically disturbed minesoils and subsequent planting of trees and/or grasses can result in a rapid build-up of carbon (C) in the soil. However, the amount of C sequestered in reclaimed minesoils may vary with the amount of time since reclamation. In this study, we assessed total carbon (TC) and total nitrogen (TN) concentrations for reclaimed minesoils located in northeastern Ohio and characterized by distinct reclamation age chronosequences. Reclaimed minesoils studied were R78G, reclaimed in 1978 and immediately seeded to grass; R82GT, reclaimed in 1982 and immediately seeded to grass and trees were planted 5 years later; and R87G, reclaimed in 1987 and immediately seeded to grass. An unmined site, UMG, was also included as a reference. Our objectives were to evaluate the variability with respect to mean and the spatial variability of pH, bulk density (,b), TC and TN concentrations, and stocks in each reclaimed minesoil. Thirty soil samples were collected at each of the 0,15, 15,30, and 30,50,cm depth. The coefficient of variation (CV) for ,b was least, <15 per cent at each site and depth. For TN concentration and stock, CV was moderate, 15,35 per cent, in each field except the UMG where it was high, >35 per cent at 0,15, and 15,30,cm depths. For TC concentration and stocks, CV was high, >35 per cent, across all minesoils and generally increased with depth. The C/N ratio followed the same tend as TC and TN stocks and ranged from 40 per cent to 123 per cent across minesoils. Geostatistical analysis also showed an increase in sample variance with increasing amount of time since reclamation for most soil properties under investigation. Sample variance for TC concentration and stocks also increased with depth in reclaimed minesoils. However, no definite relationship emerged between amount of time since reclamation and the spatial dependence of TC and TN concentrations and stocks. Overall this study showed that reclamation of drastically disturbed minesoils increased the soil C concentration and stocks and reclamation by initially seeding to grasses followed by planting trees was the best management option for speedy accretion of soil C and soil quality enhancement. Copyright © 2007 John Wiley & Sons, Ltd. [source] Subsurface drainage for reversing degradation of waterlogged saline landsLAND DEGRADATION AND DEVELOPMENT, Issue 6 2006D. P. Sharma Abstract In irrigated agriculture of arid and semiarid regions waterlogging coupled with salinity is a serious problem. Experimental evidence at several locations has led to the realization that subsurface drainage is an essential intervention to reverse the processes of land degradation responsible for the formation of waterlogged saline lands. This paper presents the results of a study conducted from 1995 to 2000 to evaluate the impacts of subsurface drainage on soil properties, groundwater-table behaviour and crop productivity in a waterlogged saline area of 2200,ha. A subsurface drainage system was installed at 1·6,m depth with 60,m drain spacing covering an area of 1200,ha (23 blocks) during 1997,99 and compared with an undrained block of 1000,ha. Subsurface drainage facilitated the reclamation of waterlogged saline lands and a decrease in the soil salinity (ECe, dS,m,1) that ranged from 16·0 to 66·3,per,cent in different blocks. On average, 35·7,per,cent decrease in salt content was observed when compared with the initial value. Provision of subsurface drainage controlled the water-table below the root zone during the monsoon season and helped in bringing the soil to optimum moisture content for the sowing of winter crops. In the drained area, the increase in yields of different crops ranged from 18·8 to 27·6,per,cent. However, in the undrained area the yield of different crops decreased due to the increased waterlogging and soil salinity problems. Overall the results indicated that investment in subsurface drainage is a viable option for reversing the land degradation of waterlogged saline lands in a monsoon climate. Copyright © 2006 John Wiley & Sons, Ltd. [source] The use of coal fly ash in sodic soil reclamationLAND DEGRADATION AND DEVELOPMENT, Issue 3 2003D. Kumar Abstract An experiment was conducted for two years in northwest India to explore the feasibility of using coal fly ash for reclamation of waterlogged sodic soils and its resultant effects on plant growth in padi,wheat rotation. The initial pH, electrical conductivity, exchangeable sodium percentage and sodium adsorption ratio of the experimental soil were 9.07, 3.87,dS,m,1, 26.0 and 4.77 (me l),1/2, respectively. The fly ash obtained from electrostatic precipitators of thermal power plant had a pH of 5.89 and electrical conductivity of 0.88,dS,m,1. The treatments comprised of fly ash levels of 0.0, 1.5, 3.0, 4.5, 6.0 and 7.5 per cent, used alone as well as in combination with 100, 80, 60, 40, 20 and 10 per cent gypsum requirement of the soil, respectively. There was a slight reduction in soil pH while electrical conductivity of the soil decreased significantly with fly ash as measured after padi and wheat crops. The sodium adsorption ratio of the soil decreased with increasing fly ash levels, while gypsum treatments considerably added to its favourable effects. Fly ash application increased the available elemental status of N, K, Ca, Mg, S, Fe, Mn, B, Mo, Al, Pb, Ni, Co, but decreased Na, P and Zn in the soil. An application of fly ash to the soil also increased the concentrations of above elements except Na, P and Zn in the seeds and straw of padi and wheat crops. The available as well as elemental concentrations in the plants was maximum in the 0 per cent fly ash,+,100 per cent gypsum requirement treatment except Na and heavy elements like Ni, Co, Cr. The treatment effects were greater in the fly ash,+,gypsum requirement combinations as compared to fly ash alone. Saturated hydraulic conductivity and soil water retention generally improved with the addition of fly ash while bulk density decreased. Application of fly ash up to 4.5 per cent level increased the straw and grain yield of padi and wheat crops significantly in both years. The results indicated that for reclaiming sodic soils of the southwest Punjab, gypsum could possibly be substituted up to 40 per cent of the gypsum requirement with 3.0 per cent acidic fly ash. Copyright © 2003 John Wiley & Sons, Ltd. [source] Selection of Leucaena species for afforestation and amelioration of sodic soilsLAND DEGRADATION AND DEVELOPMENT, Issue 5 2002V. L. Goel Abstract Performance of three exotic species of Leucaena (L. diversifolia, L. shannonii and L. leucocephala) and one local selection of L. leucocephala was evaluated on sodic soil sites (pH 8.6,10.5) in order to select promising species for biomass production and reclamation of these soils. There were significant differences among three species with respect to their field survival (47.7,95.5 per cent), growth in terms of stem volume (40.8,118.6,m3,ha,1) and biomass production (24,70,Mg,ha,1) after eight years of growth. L. leucocephala was rated as the most promising species irrespective of seed source, followed by L. shannonii. L. diversifolia could not perform well on these hostile soils. A definite improvement in physicochemical properties of soil particularly in surface layers (0,5,cm) was observed after eight years of plantations as compared to the same at uncultivated site. The soil pH and sodium content decreased followed by an increase in organic carbon, nitrogen and phosphorus content. However, efficiency of different species varied greatly to ameliorate these soils depending on quantity and quality of organic matter lying on the floor. L. leucocephala, irrespective of seed origin, showed greater promise for afforestation of sodic soils because of its potential to produce higher biomass per unit area and greater efficiency to ameliorate fertility status of these soils. The study revealed that matching of species to soil conditions is very important for a successful plantation programme and sustainable development of degraded soil sites. Copyright © 2002 John Wiley & Sons, Ltd. [source] Conservation of gullies in susceptible riparian areas of alluvial soil regionsLAND DEGRADATION AND DEVELOPMENT, Issue 3 2002R. C. Yadav Abstract The problem of gully erosion is very severe in the riparian areas of the alluvial deep soil region in India. Research and development have progressed in response to the change in social needs. The earlier strategy of maintenance of law and order has changed to one of reclamation and restoration of the productive capacity of riparian areas. Watershed management in the ravines has been adopted for development of food security, eco-restoration and pollution control. Case studies on the watershed management in watersheds projects initiated in the mid-1980s revealed the scope for bringing increased prosperity through crop diversification and eco-restoration. In consideration of the erosion process, new concepts of management zones and improved conservation and reclamation practices have been developed. The sociological factors have been rationally analysed, as they applied to watershed management in the ravines. A new paradigm of watershed management by group action is necessary in the future. Since the ways of combating the ravine problem and enhancing the productivity of ravine-degraded lands were made on rational process-based approach, there is scope for it to be implemented in other countries with similar land and socio-economic situations. Copyright © 2002 John Wiley & Sons, Ltd. [source] | ||||||||||||||||||||||