Imagining the Dirty Green City

ABSTRACT

The green city is being elevated to the status of a self-evident good in the theory and practice of urban sustainability. A large literature documents the linked environmental, economic and well-being benefits associated with vegetating urban systems to maximise the ecosystem function. Contemporary urban greening seeks to challenge attempts to expel nature from the city in a quest for order and control. However, by imagining nature as a new mode of urban purification, much effort in the name of the green city inverts and reproduces dualistic understandings of natural and built space. In response, we disrupt the normative dialectics of purity and dirt that sustain this dualism to expose the untidy but fertile ground of the green city. We draw together Ash Amin’s four registers of the Good City – relatedness, rights, repair and re-enchantment – with the artworks of the Australian visual ecologist Aviva Reed. Our work seeks to enrich the practice of more-than-human urbanism through ‘dirt thinking’ by imagining the transformative possibilities in, of and for the dirty green city.     

Application of 1D paleo‐fluvial process modelling at a basin scale to augment sparse borehole data: example of a Permian formation in the Galilee Basin,Australia

The heterogeneous hydraulic conductivity (K) in water‐bearing formations controls subsurface flow and solute transport processes. Geostatistical techniques are often employed to characterize the K distribution in space based on the correlation between K measurements. However, at the basin scale, there are often insufficient measurements for inferring the spatial correlation. This is a widespread problem that we address in this study using the example of the Betts Creek Beds (BCB) in the Galilee Basin, Australia. To address the lack of data, we use a 1D stochastic fluvial process‐based model (SFPM) to quantify the total sediment thickness, Z( x ), and the sandstone proportion over the total thickness, P_s( x ), in the BCB. The semivariograms of Z( x ) and P_s( x ) are then extracted and used in sequential Gaussian simulation to construct the 2D spatial distribution of Z( x ) and P_s( x ). P_s( x ) can be converted to a K distribution based on classical averaging methods. The results demonstrate that the combination of SFPM and geostatistical simulation allows for the evaluation of upscaled K distribution with a limited number of K measurements. Copyright © 2015 John Wiley & Sons, Ltd.     

New Fellow of the Royal Society of Chemistry (FRSC)

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New Fellow of the Royal Society of Chemistry (FRSC)     

Nutrient Limitation on Phytoplankton Growth in the Upper Barataria Basin,Louisiana: Microcosm Bioassays

The Davis Pond Diversion (DPD) was constructed to divert Mississippi River (MR) water into the Barataria Basin to reduce the salinity in support of wetland restoration on the Louisiana coast. To assess the phytoplankton nutrient limitation in adjacent water systems and potential impacts of DPD, 12 seasonal nutrient-phytoplankton bioassay experiments were conducted from October 2003 to July 2004 using the natural phytoplankton assemblages from freshwater and brackish-water lakes, Cataouatche and Salvador, LA (USA), which receive Mississippi River water from the DPD, and from a nearby freshwater lake, Lac des Allemands, that does not. Dissolved inorganic nitrogen (N), phosphorus (P), and silicate (Si) were added with different combinations at Redfield ratios in 10-l microcosms. Nitrogen was found to be the sole or primary limiting nutrient in all 12 experiments. N and P colimitations were found in seven of 12 experiments, but N was always the stronger limiting factor. P limitation was never observed to be the sole limiting nutrient. The results showed that a low concentration of P and a relatively high concentration of N do not necessarily indicate only P limitation in these lakes. Lake Cataouatche and Lake Salvador were dominated by centric diatoms, and Anabaena spp. were detected at high levels, particularly in summer. Lac des Allemands was generally dominated by N-fixing Anabaena spp. and other cyanobacteria, and their biomass responded significantly to N addition but not to P addition, indicating that nitrogen fixation in Lac des Allemands may be inhibited by other factors such as iron. Our bioassay results demonstrate that whether a water body is N- or P-limited is the consequence of the nutrient status and not the salinity regime. The results suggest that the addition of nutrient-rich waters via diversions of Mississippi River water into these lakes might increase the frequency of algal blooms, including noxious and toxic freshwater cyanobacteria.     

Biodiversity conservation and land rights in South Africa: Whither the farm dwellers?

South Africa is unique in that its globally significant biodiversity, which is under significant threat, coexists with an apartheid history of dispossession that produced a starkly unequal land ownership pattern and widespread rural poverty. It is in this context that the post-apartheid government must fulfil constitutional and international obligations to safeguard environmental assets as well as undertake land reform benefiting the previously dispossessed. Consequently, there is a continuous challenge of reconciling complex and often conflicting relationships between poverty, inequitable access to resources, and the protection of biodiversity. Current efforts to conserve the Cape Floral Kingdom emphasize partnerships between private landowners and existing nature reserves to promote sustainable utilisation of biodiversity. This paper presents a case study exploring how this approach might be reconciled with land rights and opportunities for land-based livelihoods among farm dwellers in the Baviaanskloof area of the Eastern Cape. The paper identifies systemic and structural tensions in current attempts to reconcile biodiversity conservation and farm dwellers’ interests, and documents issues of process and principle that could become important in the future. In doing so, it highlights the influence of on-farm power relations and overly complex institutional arrangements in determining the real extent of participation by affected farm dwellers and the efficacy of social safeguard policies. Findings also caution against an over-reliance on ecotourism as the major occupation and the paper argues instead for support for multiple livelihood strategies.     

Consumption preferences and environmental externalities: A hedonic analysis of the housing market in Guangzhou

The urban housing market of China has been transformed since the 1980s from a centrally-planned to a free-market system. This study aimed to (1) investigate the position of outdoor environmental quality in house-buyers’ preferences; (2) assess monetary values attributed to environmental externalities by the hedonic pricing method (HPM); and (3) test the applicability of HPM in China. The study area was Guangzhou, the major city of south China with a booming real-estate market. A questionnaire survey was conducted with households in new residences sold in 2004. The main buying motives were improving living quarters and floor area. Security concerns and a preference for high-rise buildings were somewhat unexpected. Good outdoor environment, including green space provision, proximity to parks, and views of green space and water, carried significant hedonic values. Differences between the submarkets of old and new towns were found; new town households expected apartments in high-rise blocks, exclusive residential land use, and views of green space, while old town households preferred proximity to shopping areas and workplaces, green space within the development and proximity to nearby parks. The findings could help to fine tune the developing housing market to match supply with demand in quality terms. Values accorded to environmental attributes could justify funding for urban green spaces and nature conservation. The study verified the applicability of HPM to the housing context in China.     

Evaluation of Impact of Potential Extreme Rainfall Events on Mining in Peru

Natural Resources Research - The impact that climate change may play in the future sustainability of mining projects has become increasingly important for the mining industry and its stakeholders....     

Country-Specific Market Impacts of Climate Change

We develop a new climate-impact model, theGlobal Impact Model (GIM), which combines futurescenarios, detailed spatial simulations by generalcirculation models (GCMs), sectoral features,climate-response functions, and adaptation to generatecountry-specific impacts by market sector. Estimatesare made for three future scenarios, two GCMs, andtwo climate-response functions – a reduced-form modeland a cross-sectional model. Combining empiricallybased response functions, sectoral data by country,and careful climate forecasts gives analysts a morepowerful tool for estimating market impacts. GIMpredicts that country specific results vary, implyingthat research in this area is likely to bepolicy-relevant.