Dilemmas of development in Oceania: the political economy of the Tongan agro-export sector

This article critically engages with the recent diffusion of the orthodox development model in Oceania and highlights some evolving dilemmas. In particular, it explores the social, economic and ecological tensions arising from economic reforms that are exacerbating the fragility of already vulnerable nation-states and communities. In order to illustrate its arguments, a case study of the impacts of agro-export growth in Tonga is presented. Attention is drawn to the socially inequitable and ecologically unsustainable outcomes of rapid growth in this sector. In analyzing the political economy of the squash pumpkin sector, the authors point to the important role that culture plays in mediating and conditioning development outcomes. Reflecting on the Tongan case, it is argued that to better understand the implications of orthodox developmental reform in the region, research must seek to more explicitly incorporate distributional and ethical analysis.     

The termination of the last major phase of aeolian sand movement,coastal dunefields,Denmark

Optically stimulated luminescence (OSL) dating of sand samples from stabilized (or inactive) coastal dunes in Denmark provides information on the age of the termination phase of the last major aeolian activity period. A total of 26 sand samples were taken from four different coastal dunefields around the North Sea, Skagerrak and Kattegat coasts of Denmark. The OSL dates indicate that the last major phase of aeolian activity terminated between ad 1860 and 1905. Most of the dunes examined in this study were active around 1820, during a period documented to have been very stormy. A dune management scheme started around 1792, and this no doubt was a major cause of dunefield stabilization, but an overall decline of storminess, particularly spring and summer storminess, around the end of the 19th century must also have contributed to the increasing inactivity of coastal dunes. The new OSL dates on aeolian sand movement agree well with historical data and data from topographic maps on dune movement. This agreement supports the observation from earlier work that OSL dating of recent aeolian sand movement is accurate over the last few decades to centuries. Copyright © 2005 John Wiley & Sons, Ltd.     

Large phreatomagmatic vent complex at Coombs Hills, Antarctica: Wet, explosive initiation of flood basalt volcanism in the Ferrar-Karoo LIP

The Mawson Formation and correlatives in the Transantarctic Mountains and South Africa record an early eruption episode related to the onset of Ferrar-Karoo flood basalt volcanism. Mawson Formation rocks at Coombs Hills comprise mainly (≥80% vol) structureless tuff breccia and coarse lapilli tuff cut by irregular dikes and sills, within a large vent complex (>30 km²). Quenched juvenile fragments of generally low but variable vesicularity, accretionary lapilli and country rock clasts within vent-fill, and pyroclastic density current deposits point to explosive interaction of basalt with groundwater in porous country rock and wet vent filling debris. Metre-scale dikes and pods of coherent basalt in places merge imperceptibly into peperite and then into surrounding breccia. Steeply dipping to sub-vertical depositional contacts juxtapose volcaniclastic rocks of contrasting componentry and grainsize. These sub-vertical tuff breccia zones are inferred to have formed when jets of debris + steam + water passed through unconsolidated vent-filling deposits. These jets of debris may have sometimes breached the surface to form subaerial tephra jets which fed subaerial pyroclastic density currents and fall deposits. Others, however, probably died out within vent fill before reaching the surface, allowing mixing and recycling of clasts which never reached the atmosphere. Most of the ejecta that did escape the debris-filled vents was rapidly recycled as vents broadened via lateral quarrying of country rock and bedded pyroclastic vent-rim deposits, which collapsed along the margins into individual vents. The unstratified, poorly sorted deposits comprising most of the complex are capped by tuff, lapilli tuff and tuff breccia beds inferred to have been deposited on the floor of the vent complex by pyroclastic density currents. Development of the extensive Coombs Hills vent-complex involved interaction of large volumes of magma and water. We infer that recycling of water, as well as recycling of pyroclasts, was important in maintaining water supply for phreatomagmatic interactions even when aquifer rock in the vent walls lay far from eruption sites as a consequence of vent-complex widening. The proportion of recycled water increased with vent-complex size in the same way that the proportion of recycled tephra did. Though water recycling leaves no direct rock record, the volcaniclastic deposits within the vent complex show through their lithofacies/structural architecture, lithofacies characteristics, and particle properties clear evidence for extensive and varied recycling of material as the complex evolved. Editorial responsibility: J. Donnelly-Nolan     

Luminescence dating of old (>70 ka) Chinese loess: A comparison of single-aliquot OSL and IRSL techniques

The applicability of two different approaches in the luminescence dating of old (>70 ka) Chinese loess is investigated. Both SAR-OSL ages obtained on 63–90 μm quartz grains and SAR-IRSL ages obtained on 4–11 μm polymineral grains, for samples collected from two sites in the Chinese Loess Plateau (Luochuan and Dongchuan) are presented. The characteristics of the luminescence signals stimulated by blue and infrared light are investigated in terms of dose response and dose recovery, and as a function of age. Additionally, anomalous fading measurements from the 410 nm IRSL emission in polymineral fine-grains are reported. An average value of g_2days amounting to 3% per decade was measured and seems to be independent of site location and age. For the samples from Luochuan, independent age control (pedostratigraphy and palaeomagnetism) is available. At both sites, the SAR-OSL ages are always lower than the SAR-IRSL ages after they have been corrected for anomalous fading. It seems that the quartz-based SAR-OSL ages are accurate for the younger ages, but that they underestimate the true age of deposition for loess that was deposited about 60–70 ka ago. The fading-corrected SAR-IRSL ages are in better agreement with the pedostratigraphic age control (75 and 130 ka) and allow dating beyond the quartz OSL range. Based on our results, we suggest that conventional SAR-OSL and SAR-IRSL protocols at these sites should be restricted to samples of ages not exceeding 40–50  and 100–120 ka, respectively.     

Economic consequences of consideration of permanence, leakage and additionality for soil carbon sequestration projects

This paper introduces, explains, and describes methods for addressing the issues of permanence, leakage, and additionality (PLA) of agricultural soil carbon sequestration (ASCS) activities at the project level. It is important to cast these as project-level issues, because they relate to the integrity and consistency of using location-specific ASCS projects as an offset against GHG emissions generated in other sectors (e.g., energy). The underlying objective is to understand and quantify what the net carbon benefits of an ASCS project are once we account for the fact that (1) the sequestered carbon may be stored impermanently, (2) the project may displace emissions outside the project boundaries (leakage), and (3) the project’s carbon sequestration may not be entirely additional to what would have occurred anyway under business-as-usual (no project) conditions. This article evaluates methods for identifying and estimating PLA and gauges the potential magnitude of these effects on the economic returns to a project. This work reflects ongoing collaborative efforts of the authors and Bruce McCarl (Texas A&M University), Allan Sommer, Jui-Chen Yang, and Laurel Clayton (RTI International), Sandra Brown (Winrock International), Ken Andrasko and Ben DeAngelo (US EPA), and various participants in the World Resources Institute/World Business Council workgroup to develop GHG project reporting protocols. All opinions, errors and omissions are those of the authors only.     

The Mars oxidant experiment (MOx) for Mars '96

The MOx instrument was developed to characterize the reactive nature of the martian soil. The objectives of MOx were: (1) to measure the rate of degradation of organics in the martian environment; (2) to determine if the reactions seen by the Viking biology experiments were caused by a soil oxidant and measure the reactivity of the soil and atmosphere: (3) to monitor the degradation, when exposed to the martian environment, of materials of potential use in future missions; and, finally, (4) to develop technologies and approaches that can be part of future soil analysis instrumentation. The basic approach taken in the MOx instrument was to place a variety of materials composed as thin films in contact with the soil and monitor the physical and chemical changes that result. The optical reflectance of the thin films was the primary sensing-mode. Thin films of organic materials, metals, and semiconductors were prepared. Laboratory simulations demonstrated the response of thin films to active oxidants.     

A hydrothermal deposit from explorer ridge in the northeast Pacific Ocean

Crusts composed of nontronite and ferromanganese oxides were recovered from Explorer Ridge, a spreading ridge segment in the northeastern Pacific Ocean located off the west coast of Canada. The chemical and mineralogical composition of the crusts closely resembles that of the mound-like hydrothermal deposits recently discovered at the FAMOUS site on the Mid-Atlantic Ridge and on the Galapagos spreading centre. Compositional anomalies suggest that the crusts are precipitates of hydrothermal vent solutions which were ejected discontinuously and subsequently mixed with seawater.