Reclamation Age Research Articles

Biological activity of anthropogenic soils after spoil-bank forest reclamation

The paper presents the results of relatively long-term research focused on spoil bank revitalization pro-cesses in the North Bohemian Brown Coal Basin after the first three years of observations. The biological activity of soil (namely catalase and phosphatase activity), indicators of basal and potential soil respiration, ammonification and growth, development and nutrition status of forest plantations were selected as indicators of this revitalization process. These parameters were determined in five localities of different age of reclamation where different technological approaches and tree species compositions were used. The results confirm the distinct time dependence of revitalization processes. From the aspect of biological activity older reclamations are close to natural forest soil. The enrichment of top soil layer with organic matter before the plantation (by ploughing in cellulose fibres and peat addition) increased some parameters of soil biological activity. The positive amelioration effect of black alder (<i>Alnus glutinosa</i>) was also confirmed.

English

Prevention of acid mine drainage (AMD) at surface coal mines in the Appalachian region relies greatly on minimizing ground-water contact with acid- forming materials and maximizing ground-water contact with alkalinity-yielding materials. Acid-forming materials (AFMs) are often selectively handled to minimize or prevent contact with ground water. Controlling ground-water contact with acidic- or alkaline materials depends on accurate forecasting of the level and range of fluctuation of the post-mining water table and preferred ground water flow paths within the backfill. Physical measurements and aquifer testing of more than 120 wells from 18 reclaimed mines in Kentucky, Ohio, Pennsylvania and West Virginia have improved forecasting of the post-mining ground-water flow system. Flow regime influencing factors include spoil lithology and particle size, age of reclamation, spoil thickness, distance to the final highwall, and pit floor dip angle and direction. Hydraulic conductivity (K) exhibits a broad range of 7 orders of magnitude about a mean K of 1.69 x 10 -5 meters/second. Spoil aquifer saturated thickness is related to the thickness of the spoil, spoil lithology, dip of the pit floor and distance to the highwall. Saturated spoil thickness has a 99% confidence interval of 1.86 to 3.97 meters (m) about a mean of 2.91 m. Spoil saturated zone averages 20% of the total thickness.

Predictability of surface mine spoil hydrologic properties in the Appalachian Plateau.

Prevention of acid mine drainage at surface coal mines in the Appalachian region relies to an extent on minimizing ground water contact with acid-forming materials, and maximizing ground water contact with alkalinity-yielding materials. Acid-forming materials are often selectively handled to minimize or prevent contact with ground water. Controlling ground water contact with acidic or alkaline materials depends on forecasting the level and range of fluctuation of the postmining water table within the mine backfill. Physical measurements and aquifer testing of more than 120 wells from 18 reclaimed mines in Kentucky, Ohio, Pennsylvania, and West Virginia have led to improved forecasting of the postmining ground water system. Factors that influence the ground water regime include spoil lithology and particle size, age of reclamation, spoil thickness, distance from the final highwall, and pit floor dip angle and direction. Spoil hydraulic conductivity (K) exhibits a 95% confidence interval range of six orders of magnitude about a mean K of 1.7 x 10(-5) m/sec. Spoil aquifer saturated thickness is related to the overall thickness of the spoil, the lithology of the spoil, dip of the pit floor, and distance to the highwall. Saturated spoil thickness has a 95% confidence interval of 2.2 to 3.6 m about the mean of 2.9 m. The predicted saturated zone averages 19% of the total spoil thickness.

Microbial biomarkers as an indicator of ecosystem recovery following surface mine reclamation

Increased disturbance of terrestrial ecosystems in recent years for purposes of mineral extraction has created interest in development and optimization of reclamation methodologies for these lands. Currently, criteria for judging surface mine reclamation success, or progress toward reclamation goals, predominantly rely on aboveground indicators that fail to account for the abundance and composition of soil microbiota, an essential aspect of soil health. To test the utility of fatty acid methyl ester (FAME) biomarkers as indicators of reclamation progress, FAME bacterial, fungal, and total biomass biomarkers extracted from soil of surface mine reclamation sites of different ages and an adjacent undisturbed site were compared with other indicators of reclamation progress and ecosystem stability. Our results indicate that FAME microbial biomarkers and soil organic matter (SOM) contents were greatly impacted by disturbance. Discriminant analysis of FAME bacterial, fungal and total microbial biomass biomarkers, although clearly able to discriminate between disturbed and undisturbed ecosystems, indicated a trend towards the undisturbed condition with reclamation age. The ratio of FAME bacterial to fungal biomarkers reflected changes in other indicators of soil health (SOM, inorganic N concentration), suggesting that this ratio is a useful indicator of reclamation progress.

99/03465 Characterization of hydrothermally dried low-rank coals: Walsh, D. E. et al. Miner. Metall. Process., 1999, 16, (1), 48–56

Reclamation of opencast coal mine significantly ameliorates the degraded edaphic characteristics. The long-term changes of carbon (C) and nitrogen (N) pools in reclaimed mine soils (RMSs) in the Loess Plateau, China, have not been sufficiently elucidated. In this study, six types of reclaimed forest stands (with similar reclamation age between 22 and 25-year) and three age chronosequence reclaimed croplands (2-, 7-, 18-year of reclamation) were identified in Pingshuo opencast coal mine, Shanxi Province, to determine SOC and N pools in RMSs. Adjacent, undisturbed sites of forest and cropland and unreclaimed plots were selected as references as well. The results showed that 22–25 years after reclamation, SOC and N pools differed significantly among forest RMSs, ranging from 11.66 to 69.10 Mg ha−1 and 945.14 to 3145.83 kg ha−1, respectively, among which R. pseudoacacia–P. tabulaeformis forest had the greatest SOC and N pools and sequestration rates. Moreover, SOC and N pools in cropland RMSs increased across reclamation age chronosequence, ranging from 6.44 to 19.49 Mg ha−1 and 666.55 to 1554.73 kg ha−1, respectively. The sequestration rates of SOC and N in cropland RMSs followed polynomial function across age chronosequence. C:N ratio varied among plots and tended to be higher in RMSs under the mixed forest of trees. SOC and N pools were negatively correlated with soil pH. Our study indicated that SOC and N pools could be improved across age chronosequence through well managed vegetation restoration. R. pseudoacacia–P. tabulaeformis mixed forest and H. rhamnoides monoculture forest could be effective reclamation patterns to restore SOC and N pools in Pingshuo opencast coal mine.

Microbial community in the rhizosphere of native plant species growing on reclaimed coal mine soils varying in age

Abstract Soil microorganisms in the rhizosphere are important in the revegetation and stabilization of drastically disturbed areas in the semiarid Southwest, as the microbial community is often responsible for the modification of many adverse soil properties. In this study, the soil microbial community was evaluated in the rhizosphere and the nonrhizosphere of two grass species, galleta (Hilaria jamesii,) and alkali sac‐aton (Sporobolus airoides,), and a shrub, fourwing saltbush (Atriplex canescens), growing on a reclaimed coal mine spoil 3 months to 2.25 years after topsoiling and revegetation. Many soil chemical properties and most microbial populations decreased in both soil zones with reclamation age. However, the rhizosphere of galleta and alkali sacaton still had significantly higher levels of soil N, P, organic matter (OM), and microbial populations than did the nonrhizosphere after 2.25 years of plant growth. The rhizosphere of fourwing saltbush had significantly higher EC and SAR values and funga...

Enzyme activities in reclaimed coal mine spoils and soils

The segregation and stockpiling of topsoil material may reduce enzymatic activities that may hider normal nutrient cycling processes in reclaimed minelands. The effects of topsoiling and reclamation age on dehydrogenase, nitrogenase, phosphatase, arylsulphatase, amylase, cellulase, invertase and urease activities were evaluated on three reclaimed non-top-soiled and five reclaimed topsoiled areas and compared with an undisturbed reference soil. Three months after topsoiling and revegetation, activities of the enzymes in the reclaimed areas, with the exception of dehydrogenase, were statistically equal to activities of the undisturbed soil. Most enzymes, including dehydrogenase, peaked in the next 1 or 2 years after reclamation with topsoiling and declined thereafter. A 4-year-old topsoiled site (revegetated in 1978) was statistically similar to the undisturbed soil. Amylase activity, however, was significantly lower after the fourth year compared to the undisturbed soil. The non-topsoiled areas, even after 6, 7 and 8 years, appeared to have lower enzyme activities than the younger topsoiled areas or the undisturbed soil. This trend was supported by the finding that the 4-year-old topsoiled site was more enzymatically similar to the undisturbed soil than was the 8-year-old non-topsoiled site (revegetated in 1974). The low enzyme activities found in the non-topsoiled areas may be a result of their adverse chemical and physical properties, as well as the low diversity of microorganisms. These studies demonstrate the value of topsoil use for early establishment of soil processes in reclaimed areas.