57 research outputs found
News from members: New Zealand
This year we are celebrating 50 years since the first soil/ permafrost scientific expedition in the Ross Sea Region of Antarctica. It was undertaken by Prof. John D. McCraw and Dr Graeme G. Claridge. They set off from Scott Base on the Massey Fergusson tractors that Sir Edmund Hillary took to the South Pole in 1957/58 and drove to New Harbour, from which they travelled on foot for several weeks exploring the Taylor Valley and adjacent areas. Graeme Claridge went on to become an expert on Antarctic soil chemistry and, with Iain Campbell, authored the most authoritative book available on the soils of Antarctica. Both McCraw and Claridge are fit and well - (permafrost and cryosol research must be good for you) and we will be holding a celebration to mark their original journey in November this year
Once despised now desired: innovative land use and management of multilayered Pumice Soils in the Taupo and Galatea areas, central North Island, New Zealand
The tour brings together innovative land use change and management associated with dairy farming, and land-based effluent disposal, on weakly weathered and multi-layered, glass-rich, Pumice Soils (Vitrands) in the Taupo and Galatea areas. These changes and their effects, together with environmental and sustainability issues, form a central theme of the trip. Four main stops are planned, two before lunch and two after: (1) plantation pine-to-dairy farm conversion and impacts, the Taupo eruption deposits (AD 232 ± 10) and the Taupo soil, at Tahorakuri; (2) overview of the application of secondary-treated wastewater and nitrogen leaching and uptake, Rotokawa; (3) a sequence of five Holocene tephras and buried soils, including Kaharoa eruption deposits (AD 1314 ± 12) and the Galatea soil, Smeith Farm, Murupara; and (4) enhancing pasture production on ‘new’ soils formed by excavating and mixing (‘flipping’) buried soil horizons (paleosols) on Smeith’s farm. During the trip − which helps mark Waikato University’s 50th anniversary − we will see a spectacular range of volcanic and fluvial landscapes and deposits, together with impacts of tectonism, as we traverse the famous Taupo Volcanic Zone ((TVZ) in the central volcanic region. Landforms and soils dominated by tephras (volcanic ash) become generally younger towards the loci of volcanic activity. Extensive areas of soils have been formed repeatedly from the fragmental eruptive products of the two most frequently active and productive rhyolite (silica-rich) volcanic centres known, namely Taupo and Okataina. Thus soil stratigraphy and upbuilding pedogenesis form a second theme on the trip. The first part of the guidebook thus contains sections including (i) volcanism and its products, (ii) Quaternary volcanism in TVZ including deposits erupted recently from Taupo and Tarawera volcanoes from which Pumice Soils have been formed, (iii) tephra-derived soils including Pumice Soils, their classification, special problems, and (low) fertility, (iv) allophane and its formation, and (v) the interplay between geological and pedological processes relating to tephras (upbuilding pedogenesis). The second part then comprises notes and illustrations pertaining to each stop (note that figure and table numbers are self-contained at each stop, or not used). Broad overviews of the region’s geology are covered by Leonard et al. (2010), and the soils are outlined by Rijkse and Guinto (2010) and S-map. Further compilations of data are available in tour guides by Lowe (2008) and Lowe et al. (2010)
Characterization of active layer water contents in the McMurdo Sound region, Antarctica
The liquid soil water contents in the seasonally thawed layer (active layer) were characterized from seven soil climate monitoring sites - four coastal sites from south to north (Minna Bluff, Scott Base, Marble Point and Granite Harbour), and inland sites from low to high altitude (Wright Valley, Victoria Valley and Mount Fleming). Mean water contents ranged from 0.013 m³ m⁻³ near the surface at Victoria Valley to 0.013 m³ m⁻³ near the ice-cemented layer at Granite Harbour. The coastal sites have greater soil water contents than the McMurdo Dry Valley and Mount Fleming sites, and moisture contents increase with depth in the active layer. The Wright Valley site receives very little infiltration from snowmelt, with none in most years. All other sites, except Mount Fleming, received between one and four wetting events per summer, and infiltrated water moved to greater depths (≈ 10–25 cm). The Scott Base and Granite Harbour sites are on sloping ground and receive a subsurface flow of water along the ice-cemented permafrost. Our findings indicate that water contents are low with very little recharge, are greatly influenced by the local microclimate and topography, and show no significant increasing or decreasing trend over 10 years of monitoring
The effect of human activities on moisture content of soils and underlying permafrost from the McMurdo Sound region, Antarctica
Soils and the underlying permafrost from undisturbed sites and sites that had been disturbed by construction activities at Marble Point and Pram Point in the McMurdo Sound region were sampled from excavated pits and drill cores. Gravimetric moisture (ice) contents and particle size distribution were determined. Volumetric moisture contents were calculated from these results. At undisturbed sites soil moisture contents within the active layer (to c. 60 cm depth) were low and ranged from 0.5% by weight at the soil surface to 10% above the permafrost. The permafrost was generally completely saturated with ice, but sometimes contained considerable excess ice, with ice contents rising as high as 80% by volume. At disturbed sites, soil moisture contents within the active layer were similar to those of the undisturbed sites (generally <10% by weight) but within the permafrost, moisture contents were lower and less variable than in the undisturbed sites, rarely exceeding 20% by weight. The release of considerable quantities of water from the permafrost as a result of land disturbance during construction activities caused stream flows, soil shrinkage, land slumping and salinisation, resulting in significant permanent environmental damage. At Marble Point there has been no significant re-establishment of icy permafrost in the disturbed soils in the 30 years since land disturbance occurred
Visual recovery of desert pavement surfaces following impacts from vehicle and foot traffic in the Ross Sea region of Antarctica
Sites of past human activity were investigated to assess the visual recovery of the desert pavement following impacts from human trampling and vehicle traffic. Visually disturbed and nearby control sites were assessed using comparative photographic records, a field-based Visual Site Assessment, and Desert Pavement Recovery Assessment. Sites included: vehicle and walking tracks at Marble Point and Taylor Valley; a campsite, experimental treading trial site, and vehicle tracks in Wright Valley; and vehicle and walking tracks at Cape Roberts. The time since last disturbance ranged from three months to over 50 years. This investigation also attempted to determine what has the greatest lasting visual impact on soil surfaces in the Ross Sea region: dispersed trafficking or track formation? Walking tracks remained visible in the landscape (due to larger clasts concentrating along track margins) long after the desert pavement surface had recovered. However, randomly dispersed footprints were undetectable within five years. For many sites, allowing widespread trampling will give lower medium-term visible impact than concentrating traffic flow by track formation. For steep slopes and sites where repeated visits occur, use of a single track is recommended. Some 1950s vehicle tracks remain visible in the Antarctic landscape, but where visually obvious impacts were remediated, evidence of former occupation was almost undetectable
Soils of western Wright Valley, Antarctica
Western Wright Valley, from Wright Upper Glacier to the western end of the Dais, can be divided into three broad geomorphic regions: the elevated Labyrinth, the narrow Dais which is connected to the Labyrinth, and the North and South forks which are bifurcated by the Dais. Soil associations of Typic Haplorthels/Haploturbels with ice-cemented permafrost at 70 cm. They are developed in situ in strongly weathered drift with very low surface boulder frequency and occur on the upper erosion surface of the Labyrinth and on the Dais. Typic Anhyorthels also occur at lower elevation on sinuous and patchy Wright Upper III drift within the forks. Salic Aquorthels exist only in the South Fork marginal to Don Juan Pond, whereas Salic Haplorthels occur in low areas of both South and North forks where any water table is> 50 cm. Most soils within the study area have an alkaline pH dominated by Na+ and Cl- ions. The low salt accumulation within Haplorthels/Haploturbels may be due to limited depth of soil development and possibly leaching
Temporal and spatial variation in active layer depth in the McMurdo Sound Region, Antarctica
A soil climate monitoring network, consisting of seven automated weather stations, was established between 1999 and 2003, ranging from Minna Bluff to Granite Harbour and from near sea level to about 1700m on the edge of the polar plateau. Active layer depth was calculated for each site for eight successive summers from 1999/2000 to 2006/2007. The active layer depth varied from year to year and was deepest in the warm summer of 2001–02 at all recording sites. No trends of overall increase or decrease in active layer depth were evident across the up-to-eight years of data investigated. Average active layer depth decreased with increasing latitude from Granite Harbour (778S, active layer depth of.90 cm) to Minna Bluff (78.58S, active layer depth of 22 ± 0.4 cm), and decreased with increasing altitude from Marble Point (50m altitude, active layer depth of 49 ± 9 cm) through to Mount Fleming (1700m altitude, active layer depth of 6 ± 2 cm). When all data from the sites were grouped together and used to predict active layer depth the mean summer air temperature, mean winter air temperature, total summer solar radiation and mean summer wind speed explained 73% of the variation (R250.73)
Regional Assessment of Soil Change in Antarctica
Antarctica has a total area of 13.9 × 106 km², of which 44 890 km² (0.32 percent) is ice-free (Fox and Cooper, 1994; British Antarctic Survey, 2005) with potential for soil development. Ice free areas are mainly confined to the Antarctic Peninsula, a few places around the perimeter of the continent and along the Transantarctic Mountains. The largest ice-free area (approximately 5 000 km²) is the McMurdo Dry Valleys in the Ross Sea Region
Soils of Seabee Hook, Cape Hallett, northern Victoria Land, Antarctica
The soils of the Seabee Hook area of Cape Hallett in northern Victoria Land, Antarctica, were mapped and characterized. Seabee Hook is a low-lying gravel spit of beach deposits built up by coastal currents carrying basalt material from nearby cliffs. Seabee Hook is the location of an Adélie penguin (Pygoscelis adeliae) colony which influences the soils with additions of guano, dead birds, eggshells and feathers. A soil-landscape model was developed and a soil association was identified between the soils formed on mounds (relict beach ridges) favoured by penguins for nests (Typic Haplorthel) and the soils in the areas between the mounds (Typic Haplorthel/Typic Aquorthel). Soils formed on the mounds inhabited by penguins contained guano in the upper 50 cm, overlying sub-rounded beach-deposited gravel and sand. Soils between mounds had a thin veneer (< 5 cm) of guano overlying basaltic gravelly sand similar to that in the lower parts of the mound soils. The soils had high concentrations of nitrogen, organic carbon, phosphorus, cadmium, zinc, copper, and increased electrical conductivity, within horizons influenced by penguin guano. Five buried penguin bones were collected from the base of soil profiles and radiocarbon dated. The dates indicate that Seabee Hook has been colonized by penguins for at least 1000 years
Heavy metal contamination in some soils of the McMurdo Sound region, Antarctica
Soil samples from eight sites at Marble Point and Pram Point, McMurdo Sound region, contaminated by human activities were examined for heavy metal content, using sequential extraction methods. The redistribution of lead, zinc and copper arising from point sources of these metals was demonstrated. The levels found are not considered to represent serious pollution but do indicate that human activities can change the chemistry of the Antarctic environment in localized areas
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