The role of learning in sustainable communities of practice

This paper adds to the literature on skills for sustainable communities by examining the role and processes of learning in “communities of practice” that exist within a “grassroots association”. Interviews were conducted with participants in the communities of practice of a student group called Green Action, which engages with environmental issues in practical ways. The findings demonstrate how learning occurred in the communities of practice, how participants gained skills and knowledge for sustainable consumption, and how learning in the communities of practice appeared to help Green Action to sustain itself in the long-term. This paper could serve as a useful demonstration to others as to how to apply the theories and concepts from the literature on communities of practice when researching skills and knowledge for sustainable communities. It also has some value for grassroots associations themselves in understanding their own activities.     

THE ECONOMICS OF GEOTHERMAL POWER

This article, based on a rapporteur's report, is a synthesis of papers read before the United Nations Symposium on the Development and Utilization of Geothermal Resources, held at Pisa, Italy, in 1970. It covers a broad cross-section of experience in exploiting geothermal energy, especially in Hungary, Iceland, Italy, Japan, New Zealand, the Union of Soviet Socialist Republics and the United States of America     

Monitoring and management of streambank erosion and natural revegetation on the lower Gordon River,Tasmanian Wilderness World Heritage Area,Australia

The wash from high-speed tourist cruise launches causes erosion of the formerly stable banks of the lower Gordon River within the Tasmanian Wilderness World Heritage Area. Speed and access restrictions on the operation of commercial cruise vessels have considerably slowed, but not halted erosion, which continues on the now destabilized banks. To assess the effectiveness of restrictions, bank erosion and natural revegetation are monitored at 48 sites using erosion pins, survey transects, and vegetation quadrats. The subjectively chosen sites are grouped on the basis of geomorphology and bank materials. The mean measured rate of erosion of estuarine banks slowed from 210 to 19 mm/year with the introduction of a 9 knot speed limit. In areas where cruise vessels continue to operate, alluvial banks were eroded at a mean rate of 11 mm/yr during the three-year period of the current management regime. Very similar alluvial banks no longer subject to commercial cruise boat traffic eroded at the slower mean rate of 3 mm/yr. Sandy levee banks have retreated an estimated maximum 10 m during the last 10–15 years. The mean rate of bank retreat slowed from 112 to 13 mm/yr with the exclusion of cruise vessels from the leveed section of the river. Revegetation of the eroded banks is proceeding slowly; however, since the major bank colonizers are very slow growing tree species, it is likely to be decades until revegetation can contribute substantially to bank stability.     

Regional climate change projections for the Northeast USA

Climate projections at relevant temporal and spatial scales are essential to assess potential future climate change impacts on climatologically diverse regions such as the northeast United States. Here, we show how both statistical and dynamical downscaling methods applied to relatively coarse-scale atmosphere-ocean general circulation model output are able to improve simulation of spatial and temporal variability in temperature and precipitation across the region. We then develop high-resolution projections of future climate change across the northeast USA, using IPCC SRES emission scenarios combined with these downscaling methods. The projections show increases in temperature that are larger at higher latitudes and inland, as well as the potential for changing precipitation patterns, particularly along the coast. While the absolute magnitude of change expected over the coming century depends on the sensitivity of the climate system to human forcing, significantly higher increases in temperature and in winter precipitation are expected under a higher as compared to lower scenario of future emissions from human activities.     

Normalising the Crisis in Africa

Developmental relief has become the central doctrine of 'good practice' in humanitarian responses to complex political emergencies. This is despite the fact that a proliferation of such emergencies reflects a failure of development for people in those countries in crisis. Drawing on case study material from Sudan, Somalia, Rwanda and Uganda, this paper challenges assumptions made about the efficacy of developmental relief models in complex emergencies. The trend towards developmental relief practices coincides with an increasing acceptance of higher levels of humanitarian distress in Africa. Myths of aid dependency and the pursuit of sustainable programming in the midst of war are linked to a global reduction in aid. The mantra of 'local solutions to local problems' locates the causes of crises firmly within those societies in crisis. It provides a premise for international disengagement, and the denial of international responsibility for the genesis and prolongation of humanitarian crises in Africa. Assigning solutions to the poor, the marginalised and victimised through enhanced 'participation' and local financing of services sustains a myth that development is occurring, when in fact levels of distress are rising.     

A generalised sorption model for the concentration dependent uptake of caesium by argillaceous rocks

A three-site cation exchange model is proposed to describe the concentration dependent uptake of Cs on natural argillaceous rock systems. Major premises in the model are that the sorption of Cs is dominated by the illite mineral component in the rock and that there is a fixed relationship between the site capacities of the three site types denoted as frayed edge, type II and planar sites. The definition of a “reference illite” with a cation exchange capacity of 0.2 equiv. kg^-1 allows the three site capacities to be fixed in the model calculations over the weight fraction of illite in the argillaceous rocks. Up to Cs equilibrium concentrations of 10^-3 M sorption occurs predominantly on the frayed edge and type II sites (higher affinity sites), with the planar site type playing only a minor role. Competition with Cs for sorption on the former two site types arises predominantly from monovalent cations such as K, Rb and NH₄ which have low hydration energies. H and Na (except at high concentrations) are considerably less competitive and bivalent cations such as Mg, Ca and Sr are effectively non-competitive. A consistent set of selectivity coefficients for Cs with respect to K, Rb, NH₄ and Na was derived from analyses and modelling of a wide range of Cs sorption data available in the open literature on pure illites from many different sources. The model was tested against four Cs sorption isotherm data sets determined on argillaceous rocks: Boom clay, Oxford clay, Palfris marl and Opalinus clay. The water chemistries and illite contents given in these experiments allowed the Cs sorption isotherms to be predicted. It is concluded that the Cs sorption model presented here, in which there are no free parameters, can be used to predict the uptake of Cs at equilibrium concentrations below 10^-3 M to within a factor of 2 to 3 in natural argillaceous rock systems.     

Sexual selection in lekking sage grouse: phenotypic correlates of male mating success

Summary Mate choice cues in sage grouse were reinvestigated by analyzing relationships between male mating success and a range of suggested cues. Display cues were implicated by significant relationships between mating status (whether or not a male mated) and lek attendance, display rate (corrected for effects of female proximity and time of day) and an acoustic component related to temporal and frequency measure of a whistle emltted during the strut display. Although display rate and the acoustic component were intercorrelated, both exerted significant partial effects on mating success in mutivariate analyses. These display measures also differed significantly between males. In contrast, mating success was not significantly related to measures of territory characteristics, including size and proximity to the lek center, or to body size. These results resolve discrepancies between previous studies and provide a basis for experimental analysis of the role of female choice in this lek system.     

Conflict, the Continuum and Chronic Emergencies: A Critical Analysis of the Scope for Linking Relief, Rehabilitation and Development Planning in Sudan

The concept of the ‘relief-to-development continuum’ has been the subject of renewed interest in recent years. Concerned by the rise in relief budgets over the past decade and the absolute fall in development aid resources, support has been growing for the concept of developmental relief. In the context of complex political emergencies, it has been argued further that as effective development aid can reduce vulnerability to the impact of natural hazards, so it might also be used to contribute to a process of conflict prevention. In this way, the concept of the relief-development continuum has become entwined with broader discussions about the contribution of official development assistance to conflict management. Drawing on a Review of Operation Lifeline Sudan (OLS), this paper cautions against uncritical application of the concept of the continuum in complex political emergencies, and of rehabilitation in particular, in the current Sudanese context. It argues that in order to move legitimately from relief aid programming to development aid programming, three fundamental conditions must be in place: first, a minimum level of security, respect for human rights and humanitarian access. Second, empirical evidence from the field needs to demonstrate that the emergency is over. Finally, moving from relief to development aid programming is contingent on donor governments accepting the legitimacy of national governmental structures and of the rebel movements. In other words, for donor governments, moving along the continuum is in significant part determined by foreign policy considerations, not only technical ones. Consideration needs to be given to the actual and perceived legitimation of the different movements that a move to rehabilitation might be seen to imply. The paper argues that none of these conditions had been satisfied in Sudan by mid-1997. Instead of a process of normalisation paving the way to long-term development, the current situation in Sudan is better described as a chronic political emergency. In such a context, uncritical pursuit of developmental strategies may negatively affect the welfare of conflict-affected populations.