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Two-metre-deep soil profiles at 10 acid sulfate soil (ASS) scalds along the coast of New South Wales (NSW), Australia, were examined for salinity indicators. At 5 of the sites, permanently vegetated areas adjacent to the ASS-scalded land were also tested. Throughout the profiles, most sites had high soluble chloride ([Cl.sup.-]) concentrations (≤ 17 mg/g soil) and high soluble sulfate (S[O.sub.4.sup.2-]) concentrations (≤ 17 mg/g soil). Very low [Cl.sup.-] : S[O.sub.4.sup.2-] ratios (≤ 3) indicated active pyrite oxidation. Soil salinity (measured as electrical conductivity, EC) was extremely high in the top 2 m of most of the ASS scalds when related to the growth requirements of the typical introduced pasture species that were planted in these areas following drainage. This allows salinity, in addition to the extremely low pH of the surface soils, to contribute to land denudation, which can instigate or perpetuate pyrite oxidation and ASS-related land scalding. Although the sites had shallow watertables and soil-moisture content was high, the surface soil (top 0.10 m) of the scalds had consistently higher soluble [Cl.sup.-] and S[O.sub.4.sup.2-] concentrations and EC than adjacent vegetated areas. All coastal ASS areas investigated, typically freshwater backswamps used for cattle grazing, were underlain by estuarine-derived sediments containing saline ground water. The results demonstrate that revegetation of ASS scalds must include investigation and management of salinity, in addition to acidity, within the soil profile and at the soil surface. Additional keywords: Write oxidation, acid sulfate soil scald, acid sulfate soil salinity, backswamp management, backswamp drainage., Introduction The coastal floodplains in New South Wales (NSW), Australia are largely infilled barrier estuaries (Roy 1984). Extensive estuarine deposits, containing pyrite, were laid down approximately 10 000-6000 years ago [...]

Fifty-five paleolimnological records from lakes in the circumpolar Arctic reveal widespread species changes and ecological reorganizations in algae and invertebrate communities since approximately anno Domini 1850. The remoteness of these sites, coupled with the ecological characteristics of taxa involved, indicate that changes are primarily driven by climate warming through lengthening of the summer growing season and related limnological changes. The widespread distribution and similar character of these changes indicate that the opportunity to study arctic ecosystems unaffected by human influences may have disappeared. climate change | paleolimnology | Anthropocene | warming | indicators

Soil profiles in 10 persistently bare areas (i.e. scalds), mainly located in coastal backswamps of New South Wales, Australia, were examined for chromium-reducible sulfur content and selected chemical properties. At 5 of the sites, the adjacent paddocks with vegetation cover were also examined. All of the tested sites had been affected by the extensive drainage of the surrounding acid sulfate soil (ASS) landscapes and the consequent oxidation of pyrite. All sites had low pH values in the surface soil layers and these low pH values extended for up to 150 cm into the underlying unoxidised blue/grey pyritic estuarine gels. This can be attributed to the downward diffusion of acidity, either produced in the overlying oxidised zones of these soils or transported laterally across the landscape to these low-lying areas. Acidified unoxidised pyritic zones 120 cm thick can evidently form within several decades after drainage disturbance. At the scalded sites the depth from the soil surface to the main pyritic zone varied from the surface to >200 cm depth, indicating that this variable is not critical to ASS scald formation. For most of the sites examined, the chromium-reducible sulfur contents in the surface soil layers were appreciably higher than those in the immediately underlying soil layers. In most of the vegetated sites the chromium-reducible sulfur content in the surface layers was considerably higher than for the adjacent scalded site. The conditions necessary for pyrite formation (i.e. adequate supplies of organic matter, soluble iron, sulfate, and waterlogging) were found to exist at all sites, and the pyrite accumulations in these surface soil layers are considered to be neo-formed. The vegetated soil-profile pyrite and pH results were very similar to their scalded counterparts except that they had an extra 20-40 cm layer of vegetation and mulch that was missing from the scalded profiles. This indicates that there is considerable potential for more extensive scalding in these ASS areas. Additional keywords: subsurface pyrite, surface pyrite, pyrite oxidation, pyrite re-formation, acid sulfate soil pH, backswamp management, backswamp drainage., Introduction Acid sulfate soil (ASS) scalds are persistently bare areas of land associated with pyrite oxidation and ASS formation in drained coastal floodplains. In Australia, ASS scalds have not previously [...]

Acid sulfate soil (ASS) scalds are persistently bare areas of land, occurring in the coastal backswamps of New South Wales (NSW), Australia. This study aims to understand why particular areas become ASS scalds, while adjacent areas remain vegetated. Some important soil parameters are compared and field observations are summarised. Soil core sampling in both ASS-scalded land and surrounding areas of permanently vegetated paddocks has demonstrated similar pyrite concentrations and depth occurrence, soil salinity, and soil acidity (pH). As conditions are similar beneath both vegetated and non-vegetated land, there must be some additional factors influencing which areas become denuded. Several disparate (usually human-induced) events were found to cause initial loss of vegetative cover. Once the soil is bare, surface evaporation causes toxic solutes to build up quickly at the soil surface and ASS scalding is perpetuated. Some of the intervening events include fire, flood, flood-scouting, deliberate topsoil removal, surface pyrite oxidation, saltwater inundation of freshwater paddocks, saltwater exclusion from saltmarsh or mangroves, changes to the vegetation regimes, excessive vehicular traffic, and over-grazing. Backswamp management needs to ensure that land underlain by shallow pyritic layers (or with soil-water that is enriched with the toxic by-products of pyrite oxidation) is not laid bare by accident or design. Similar soil chemical conditions underlying both ASS scalds and the surrounding permanently vegetated paddocks suggest that much larger areas are potentially at risk of ASS scalding. Additional keywords: pyrite oxidation, acid sulfate soil acidity, acid sulfate soil salinity, surface pyrite, subsurface pyrite, backswamp management, backswamp drainage., Introduction Coastal floodplains in New South Wales (NSW), Australia, are underlain by formerly estuarine sediments (Roy 1984). These estuary basin and intertidal muds contain large amounts of sulfides (mainly pyrite) [...]

A comparison of the dynamic motions of squash players of differing technical capacities involved relating them to strategies used by different standard players. Provincial and Elite players showed lesser accelerations and velocities at the end of winning rallies than at the end of losing rallies. Difference in accelerations while winning or losing were absent for recreational players. Longitudinal movement was solely responsible for the differences observed in the overall velocity.

A nationwide survey on plagiarism was conducted on editors across the country. Views were solicited on the definition of plagiarism, how modern technology has affected this unethical practice, how not naming sources has affected news standards, whether or not they possess written policies on the lifting of sources and lastly, what the newspaper industry must do to improve its image. All respondents agreed that plagiarism is a serious problem that needs to be resolved in order to raise the news industry's ethical standards.

Byline: Romain Murenzi, Mike Hughes It is evident that strategies need to be undertaken to reverse the decline of Africa's share of world trade. This paper argues that through the development of regional and sub-regional integration, coupled with the development of national science and technological innovative and entrepreneurship skills, the fortunes can be reversed. The study focuses on Rwanda and reviews the policies and strategies to acquire and create knowledge linked to knowledge transfer and innovation to stimulate and develop the national economy in particular encouraging the private sector as an engine of growth. It emphasises the importance of regional cooperation to open larger markets and economies of scale.

It is crucial for officers to pledge their full support following the launch of a national enforcement group, says Mike Hughes. As a member of the National Association for Planning [...]