Re‐sampling for Soil‐caesium‐137 to Assess Soil Losses after a 19‐year Interval in a Hunter Valley Vineyard,New South Wales,Australia

Soils in a lower Hunter valley vineyard, New South Wales, Australia, were sampled and analysed for caesium‐137, an indicator of soil erosion status, in 1984–1985 and 2004. From the time of the vineyard's first establishment in 1971 to 1985, estimated soil losses were 250 tonnes (equivalent to 64.2 t ha^?1 yr^?1). Re‐sampling in 2004 showed that soil losses were 48 tonnes in the 19 years since 1985, equivalent to 9.7 t ha^?1 yr^?1. The decline in erosion rates may be explained by a change in land and soil management from intensive cultivation to one of no cultivation (sod culture) in 1998, and a lower annual rainfall and fewer rain‐days per year in the period from 1986 to 2004.     

Climate Aridity and Land Use Changes: A Regional‐Scale Analysis

In recent years, aridity and drought have become crucial issues at the global scale because of their environmental and socio‐economic implications. On the one hand, aridity causes a reduction in the biological and economic productivity of terrestrial ecosystems, and represents a serious threat to ecological, biogeochemical, and hydrological processes. On the other hand, human use (and abuse) of vulnerable dry land ecosystems may lead to unsustainable land management. Based on these considerations, this paper analyses the recent land cover changes observed in Latium (Italy) during the exceptionally dry period 2000–2007. More than 50% of the area investigated was classified as dry in 2004–2007 compared with 0% in 2000–2003. Moreover, climatic aridity impacted differently on semi‐natural, agricultural, and built‐up land. These findings illustrate a possible scenario for suburban Mediterranean regions: increasing aridity (mainly due to rising temperatures) mainly impacting on peri‐urban land.     

The Role of Fire Disturbance on Runoff and Erosion Processes – a Long‐Term Approach,Mt. Carmel Case Study,Israel

The Mediterranean ecosystem of Mt. Carmel, Israel, is subjected to an increasing number of forest fires of various extents and severities. The impacts of forest fires on runoff and erosion are widely documented and include increased peak flows and soil loss until the return of a vegetation cover. Most studies, however, treat fire as a single event, whereas the present study is aimed at exploring the long‐term effects of repeated forest fires on eco‐geomorphic processes. The study integrates the results of plot‐based, detailed analysis of post‐fire runoff and erosion with vegetation recovery analysis, at a temporal‐spatial scale which includes the effect of reburning. Our results indicate that forest fires lead to a significant increase in runoff and sediment yields, particularly during the first two years following the disturbance, up to five orders of magnitude higher than from the adjacent unburnt control plots.     

The Politics of Carbon Market Design: Rethinking the Techno‐politics and Post‐politics of Climate Change

Carbon markets have provided fertile ground for research on the changing nature of political contestation. MacKenzie locates a “techno‐politics” of carbon markets that creates new possibilities for a “politics of market design”. In contrast, Swyngedouw argues carbon markets are part of a “post‐political” shift that narrows potential pathways through “depoliticisation”. This article engages with these debates by examining three recent attempts to reform the ailing European Union Emissions Trading System: restricting industrial gas offsets, backloading allowance auctions and the 2030 climate and energy package. It conceptualises the respective episodes as contests over the reach, force and priority of value determinations in climate policy, emphasising the contradictory imperatives facing states on each issue. The outcomes of contestation between industry groups and environmental organisations—real but limited reforms and a consolidation of the carbon market over alternatives—demonstrate the constraints facing technocratic campaigning and the ongoing politicisation of climate change.     

Prospects for the Rural‐Urban Fringe in Australia: Observations from a Brief History of the Landscapes around Sydney and Adelaide

Despite being a major site of recent population growth and, arguably, a key arena for sustainability concerns, the rural‐urban fringe has received relatively little attention in the literature concerning Australian cities and urban policy. To address this shortcoming the authors review post‐World War II efforts to plan the rural‐urban fringes of Sydney and Adelaide and find a number of issues for contemporary policy‐makers. First, the fringe is becoming increasingly complex due to multi‐faceted demographic change, a broadening economic base and demands for better environmental management, all within the context of an evolving understanding of sustainability. Second, water resource management, partly under the auspices of integrated natural resource management, is assuming a much higher priority than in early fringe planning endeavours, which emphasised urban containment, agricultural land protection and landscape conservation. Third, and partly as a consequence of this shift of priorities, there is also evidence of changes to the nature and focus of policy tools used in the fringe, with land management concerns now cutting across traditional land use planning. Finally, and fundamentally, these observations raise questions about how future governance of the fringe should be organised. Together these four themes pose an enthralling series of challenges for policy‐makers for which much more research and discussion are needed.     

Policy of Delay: Evidence from a Bayesian Analysis of Metropolitan Land‐Use Choices

Do local policymakers strategically use delay in permitting development to forestall the growth machine? The mantras of smart growth and sustainable development assume local governments can balance the competing values of economic development, ecology, and equity interests in a community. We employ a political market framework to explain differences in local government land use decisions. This framework conceptualizes policy choices as resulting from the interplay between the aggregate policy demand by residents, developers, and environmental interests and the aggregate supply by government authorities. Delays can be imposed strategically through processes of development approval by city governments where industry strength and form of government vary within county‐level service‐delivery fragmentation. We utilize novel Bayesian multilevel modelling of data collected from 2007 and 2015 surveys of Florida city planners and find strong institutional effects and multilevel relationships.     

A 6000 Year‐old Fossil Dugong from Botany Bay: Inferences about Changes in Sydney's Climate,Sea Levels and Waterways

The excavation in the 1890s of a skeleton of the warm‐water marine mammal Dugong dugon, associated with Aboriginal artefacts, from a Botany Bay salt marsh, marked the beginning of speculation about climate and sea level change in Australia over the period of human occupation. The dugong bones have recently been dated, giving a conventional ¹⁴C age of 5520±70 years BP, which is consistent with three older ¹⁴C dates for a layer of buried trees that underlies much of the north Botany sediments. The carefully drawn cross‐sections of depositional strata produced by the original discoverers allow further interpretation of the pattern of Holocene sea‐level fluctuations in the Sydney region. Layers of estuarine sediment, such as the one containing the dugong skeleton, are inter‐bedded with peat layers containing in situ roots and stumps, suggesting that the site alternated between sub‐aerial exposure and submergence throughout the Holocene. The presence of the dugong is suggestive of warmer conditions, and its inland location indicates a more extensive Botany Bay in the recent past. This is in agreement with other work from southern New South Wales describing both warm‐water marine species and higher sea levels several thousand years ago.

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Age‐differentiated impact of land appropriation and resettlement on landless farmers: a case study of Xinghua village,China

Land appropriation and subsequent resettlement of rural inhabitants are central to urbanisation in China. Often, the result is the impoverishment of landless farmers, who are a principal source of social unrest in the country. In the literature, landless farmers are often wrongly assumed to be a homogeneous group. In contrast, this paper presents the age‐differentiated experiences of land appropriation and resettlement among farmers. Using the case study of Xinghua village in China, and by reference to data collected via surveys and interviews, we show that even within a single community, there can be significant age‐related differences in terms of compensation, livelihood changes, income, living conditions, and satisfaction. Older farmers tend to receive more compensation, and the negative impact of land appropriation is felt most acutely by middle‐aged farmers. Viewed from a broader theoretical perspective, this study demonstrates the importance of understanding the impact of land appropriation and resettlement and shows how this impact is distributed unevenly across the affected communities.     

Reconstructing dietary and environmental history from enamel isotopic analysis: time resolution of intra‐tooth sequential sampling

The carbon and oxygen isotopic composition of the mineral phase of tooth enamel is linked to diet and environment. Enamel is not remodelled once formed. Several studies of intra‐tooth isotopic variability in hypsodont mammal teeth have involved sequential sampling of enamel in order to detect changes in diet and environment during tooth formation. The possibility of exploring individual history opens the door to many applications, particularly in palaeoenvironment and herd management reconstruction. However, previous histological investigations have shown that enamel mineralization is a progressive and discontinuous process. The goal of the present study is to determine if this pattern significantly influences the time resolution of an intra‐tooth sequential sampling. Isotopic analyses (δ¹³C) were performed on tooth enamel from steers (Bos taurus) that had changed from a C₃ plant‐based diet to a C₄ plant‐based diet with very different carbon isotopic compositions. The change of diet was reflected in the mineral phase of enamel. The pattern of intra‐tooth isotopic variation suggests that completion of enamel mineralization required six to seven months. Such a lag in enamel mineralization will decrease the time resolution of enamel sequential sampling. The effects of prolonged mineralization of enamel have to be considered when interpreting patterns of intra‐tooth isotopic variations. Copyright © 2002 John Wiley & Sons, Ltd.