Generating productive topsoil substitutes from hard rock overburden in the southern appalachians

Natural soils on steeply sloping landscapes in the Appalachian coal fields of Virginia. West Virginia. Kentucky, and Tennessee are often thin, rocky, acidic and infertile, making the topsoiling of surface mined sites impractical in many cases. Topsoil substitutes composed of blasted rock fragments are commonly used in this region. The proper selection and placement of designated topsoil substitutes is therefore critical to long term reclamation success. These mine soil surfaces are not in equilibrium and with the surface environment, and it is quite difficult to diferentiate among dissolution, adsorption, desorption and precipitation reactions as these surfaces weather with time. Severe compaction limits the productivity of many otherwise suitable topsoil substitutes. A minimum non-compacted thickness of 1 m is desirable to insure long run mine soil productivity for a variety of post-mining land uses. Significant changes in the physical, chemical, and mineralogical properties of mine soils occur within one year after placement. Mine soils high in silt content often form hard vesicular surface crusts, particularly when left unvegetated. The long term survival of plant communities on these mine soils is dependent upon mine soil organic matter accumulation and N and P cycling. Little is currently known about N and P dynamics in these mine soils, but P-fixation is a profound problem in high Fe^3- spoils. Revegetation practices that were designed to meet 2-year bond release requirements may not he sufficient to meet new 5-year release standards. Hard rock derived mine soils can often equal or exceed native topsoil in productivity and post mining land use potential.     

Biosensor-based diagnostics of contaminated groundwater: assessment and remediation strategy

Shallow groundwater beneath a former airfield site in southern England has been heavily contaminated with a wide range of chlorinated solvents. The feasibility of using bacterial biosensors to complement chemical analysis and enable cost-effective, and focussed sampling has been assessed as part of a site evaluation programme. Five different biosensors, three metabolic (Vibrio fischeri, Pseudomonas fluorescens 10568 and Escherichia coli HB101) and two catabolic (Pseudomonas putida TVA8 and E. coli DH5alpha), were employed to identify areas where the availability and toxicity of pollutants is of most immediate environmental concern. The biosensors used showed different sensitivities to each other and to the groundwater samples tested. There was generally a good agreement with chemical analyses. The potential efficacy of remediation strategies was explored by coupling sample manipulation to biosensor tests. Manipulation involved sparging and charcoal treatment procedures to simulate remediative engineering solutions. Sparging was sufficient at most locations.     

The Expected Impact of the Peace Conduit Project (The Red Sea – Dead Sea Pipeline) on the Dead Sea

The Dead Sea of Israel, Jordan and Syria is a severely disturbed ecosystem, greatly damaged by anthropogenic intervention in its water balance. During the 20 th century, the Dead Sea level dropped by more than 25 meters, and presently (2003) it is at about 416 meters below mean sea level. This negative water balance is mainly due to the diversion of water from the catchment area of the lake by Israel, Jordan and Syria. During the 2002 World Summit on Sustainable Development Israel and Jordan jointly announced their interest in saving the Dead Sea by constructing the ‘Peace Conduit’ that will pipe water from the Red Sea to the Dead Sea. The inflow of seawater (or reject brine after desalinization) into the Dead Sea will have a major impact on its limnology, geochemistry and biology. During the filling stage, relatively diluted surface water will form and the rate of evaporation will therefore increase. Dilution of the surface water will most likely result in microbial blooming whose duration is not known, while the lower water layer is likely to develop reducing conditions, including bacterial sulfate reduction and presence of hydrogen sulfide (H₂S). Mixing between the calcium-rich Dead Sea brine and the sulfate-rich seawater will result in gypsum precipitation (CaSO₄·2H₂O). Once the target level is reached, inflow will be outbalanced by evaporation and salinity of the surface water will increase due to accumulation of sea water-salts. The water column will remix when the density of the surface water will equal that of the lower water column. In spite of its large volume and high salinity relative to that of the inflowing water, over the long run the composition of this unique lake will change. Before a decision is made on the planning and construction of the Conduit, it is essential that the long term evolution and characteristics of the ‘renewed’ Dead Sea be known and anticipated changes examined. Once decided upon, the planning and construction of the Conduit should be conducted so as to minimize possible negative impacts of seawater introduction on the Dead Sea. This can only be achieved through a thorough understanding of the expected changes in the limnological physical/chemical characteristics of the Dead Sea and its unique brine.     

Naproxen,ibuprofen, and diclofenac residues in river water,sediments and Eichhornia crassipes of Mbokodweni river in South Africa: An initial screening

In the last 5 years, naproxen, ibuprofen and diclofenac have been the subject of investigation in the South African water resources. In this study, their occurrence in river water, sediments and aquatic plants was investigated. The concentrations of compounds detected in river water and sediments varied from 0.59 to 2.3 µg L^?1 and 0.2 to 9.2?ng g^?1, respectively. The partitioning coefficients (L kg^?1) for naproxen, ibuprofen and diclofenac varied from one sampling location to the other in ranges of 3.36–4, 1.3–1.9 and 0.13–0.91, respectively. This indicates that the fate of these pharmaceuticals can be influenced by the surrounding conditions such as climate and presence of other water pollutants as well as differences in physicochemical parameters. In the aquatic plant species (Eichhornia crassipes), the concentrations of target compounds varied in different parts of the plant material (roots, stems and leaves). Naproxen was the most abundant in Eichhornia crassipes, with the maximum concentration of 12.0?ng g^?1 found in leaves. In this initial assessment, we found no rational trend for the concentrations detected in various parts of Eichhornia crassipes, however, it is speculated that these pharmaceuticals diffuse from water into the roots of the aquatic plants and get translocated into the stem and leaves. Overall, the occurrence of naproxen, ibuprofen and diclofenac in river water, sediments and Eichhornia crassipes was observed, which is an indication that Eichhornia crassipes has the ability to reduce water pollution through the uptake of pharmaceuticals through plant roots.     

Insecticide residues in the blood serum and domestic water source of cacao farmers in Southwestern Nigeria

The blood serum of cacao farmers and their domestic water sources were analyzed for insecticide residues in selected cacao growing communities of Southwestern Nigeria. The farmers were grouped into five exposure periods based on their years of involvement in insecticide application, viz, <5 years, 5-9 years, 10-14 years, 15-19 years and >20 years. The residue analyses revealed that 42 out of the 76 farmers had residues of diazinon, endosulfan, propoxur and lindane in their blood; and 47.6% out of these farmers belonged in the >20 years exposure duration period. About 34% of the farmers had diazinon with a mean concentration of 0.067 mg kg(-1), 29% endosulfan (mean=0.033 mg kg(-1)), 23% propoxur (mean=0.095 mg kg(-1)), and 17% lindane (mean=0.080 mg kg(-1)) in their blood. The residues of lindane, endosulfan and propoxur in all the exposure duration categories were found to be far below the no observable adverse effect level (NOAEL) while diazinon residues detected in the blood serum of the farmers in all the exposure duration categories exceeded the NOAEL of 0.02 mg kg(-1) for the insecticide. The study also revealed that the sources of drinking water had been contaminated with dazinon and propoxur in some of the farmers' localities; and the concentrations of the insecticides exceeded the acceptable daily intake (ADI). It is concluded that cacao farmers in Southwestern Nigeria may have been occupationally exposed due to insecticide application for mirid control in their cacao plantations; and the exposure at times is of such magnitude as to be hazardous to the farmers and their respective communities.     

Agricultural land use efficiency and food crop production in Ghana

Despite the low productivity of the extensive agriculture system, Ghana recorded the largest reduction of undernourishment in the past two decades. We used biophysical analysis to determine the efficiency and potentials of the extensive system and its future sustainability. The results indicate that food production in Ghana has increased steadily over the past two decades and correlated highly with cropped area and population (R ² < 0.85 and 0.82), but not with fertilizer (R ² = 0.06). Sufficient food production could be sustained in the short term. In the longer term, however, the food situation in Ghana appears precarious if population growth continues while land remains the same.     

Industrial age anthropogenic inputs of heavy metals into the pedosphere

Heavy metals have been increasingly released into our environment. We present here, for the first time, the global industrial age production of Cd, Cu, Cr, Hg, Ni, Pb, and Zn, and their potential accumulation and environmental effects in the pedosphere. World soils have been seriously polluted by Pb and Cd and slightly by Zn. The potential industrial age anthropogenic Pb, Hg, and Cd inputs in the pedosphere are 9.6, 6.1, and 5.2 times those in the lithosphere, respectively. The potential anthropogenic heavy metal inputs in the pedosphere increased tremendously after the 1950s, especially for Cr and Ni. In 2000, the cumulative industrial age anthropogenic global production of Cd, Cr, Cu, Hg, Ni, Pb, and Zn was 1.1, 105, 451, 0.64, 36, 235, and 354 million tonnes, respectively. The global industrial age metal burdens per capita (in 2000) were 0.18, 17.3, 74.2, 0.10, 5.9, 38.6, and 58.2 kg for Cd, Cr, Cu, Hg, Ni, Pb, and Zn, respectively. Acidification may increase the bioavailability and toxicity of heavy metals in the pedosphere. The improvement of industrial processing technology reducing the metal dispersion rate, the recycling of metal-containing outdated products, by-products and wastes, and the development of new substitute materials for heavy metals are possible strategies to minimize the effects of heavy metals on our environment.     

The town and country planning act 1947

The 1947 Town & Country Planning Act is regarded as the statutory foundation of physical planning in post‐war Britain. This paper looks at the Act in context and assesses its effectiveness from the vantage point of forty years since its implementation.