Urban Waterfront Regeneration in the Mersey Basin,North West England

The economic decline of traditional dockland areas has released considerable areas of land for redevelopment, much of which is close to the heart of city centres. The property development industry has capitalized upon these assets to the extent that port-related redevelopmentis a common feature throughout North America and Europe. This paper explores the experience of the Mersey Basin in North West England which, under the Mersey Basin Campaign initiative, has sought to explicitly connect improvements in water quality to economic regeneration. A small survey of commercial property valuers was used to explore this relationship and revealed the importance of water in the property development process, through potential increases in value and an enhancement of the marketability of property adjacent to water. Equally, improved water quality is revealed as an important precursor to waterside economic regeneration. Here, investment must, as with the preparation of derelict and contaminated land for redevelopment, be regarded as a public good, nurturing good water quality as an asset for the benefit of future generations and as a part of realizing the full potential of waterfront regeneration.     

Ten Years On: An Empirical Analysis of UK Environmental Statement Submissions since the Implementation of Directive 85/337/EEC

Regulations to implement Directive 85/337/EEC have been in operation in the UK for over 10 years. Implementation of the amended Directive (97/11/EC) in March 1999 marked the start of a new phase in environmental impact assessment (EIA), and so a review of the impact of the original Directive upon EIA activity is timely. This paper examines the implementation of the Directive in the UK through an empirical analysis of the publication of environmental statements (ESs) between July 1988 and April 1998. ES submissions are analysed under Annexes I and II of the Directive and under the main UK regulations, and then development control decision outcomes are considered. The implications of selected legislation and policy initiatives for ES submissions are then investigated in detail for four types of project. The Directive has been a major force in stimulating the development and growth of EIA in the UK, although the interaction of policies and legislation (environmental and otherwise) can exert an important influence upon trends in ES submissions.     

Book reviews

Sustainable Cities and Sustainable Development Sustainable Cities. G. Haughton & C. Hunter, 1994, Jessica Kingsley/Regional Studies Association, London

Sustainable Cities in Europe. P. Nijkamp & A. Perrels, 1994, Earthscan, London ISBN 185383, £12.95

Toward Sustainable Development Concepts, Methods and Policy. J. C. J. M. van den Bergh & J. van der Straaten, 1994, Island Press, Washington, DC, ISBN 1 55963 3492, £30.00

Just Environments: intergenerational, international and interspecies issues. David E. Cooper & Joy A. Palmer (Eds), 1995, London, Routledge, ISBN 0 415-10336-3, pp. 199, index, £11.99

First Steps: Local Agenda 21 in practice. Stella Whittaker (Ed.), 1995, London, HMSO, 251 pp. ISBN 0 11 701871 6, £29.95

Beyond the Car: essays on the auto culture. Sue Zielinski & Gordon Laird (Eds), 1995, Toronto, Steel Rail Publishing/Transportation Options, 191 pp. ISBN 0 88791 042 4, pbk, C$ 19.95, US$15.95     

Stormflow hydrochemistry of a river draining an abandoned metal mine: the Afon Twymyn, central Wales

Contaminated drainage from metal mines is a serious water-quality problem facing nations that exploit metal mineral resources. Measurements of river hydrochemistry during baseflow are common at mine sites, whilst detailed hydrochemical information regarding stormflow is limited and often confined to a single event. This study investigates the seasonal evolution of stormflow hydrochemistry at an abandoned metal mine in central Wales, UK, and the possible sources and mechanisms of metal release. Significant flushing of metals was observed during stormflow events, resulting in concentrations that severely exceeded water-quality guidelines. The relationship between metal concentrations and river discharge suggests dissolution of efflorescent metal sulphates on the surface of the mine spoil as the principal source of the contamination. High fluxes of Pb during stormflows are linked to extended periods of dry weather prior to storm events that produced water table drawdown and encouraged oxidation of Pb sulphide in the mine spoil. However, some Pb flushing also occurred following wet antecedent conditions. It is suggested that Fe oxide reduction in mine spoil and translatory flows involving metal-rich pore waters results in flushing during wetter periods. Detailed measurements of stormflow hydrochemistry at mine sites are essential for accurate forecasting of long-term trends in metals flux to understand metal sources and mechanisms of release, to assess potential risks to water quality and instream ecology, and to gauge the potential effectiveness of remediation. In order to protect riverine and riparian ecosystems, it is suggested that routine monitoring of stormflows becomes part of catchment management in mining-impacted regions.     

Determination of the emissions from an aircraft auxiliary power unit (APU) during the Alternative Aviation Fuel Experiment (AAFEX)

The emissions from a Garrett-AiResearch (now Honeywell) Model GTCP85–98CK auxiliary power unit (APU) were determined as part of the National Aeronautics and Space Administration's (NASA's) Alternative Aviation Fuel Experiment (AAFEX) using both JP-8 and a coal-derived Fischer Tropsch fuel (FT-2). Measurements were conducted by multiple research organizations for sulfur dioxide (SO₂), total hydrocarbons (THC), carbon monoxide (CO), carbon dioxide (CO₂), nitrogen oxides (NO_x), speciated gas-phase emissions, particulate matter (PM) mass and number, black carbon, and speciated PM. In addition, particle size distribution (PSD), number-based geometric mean particle diameter (GMD), and smoke number were also determined from the data collected. The results of the research showed PM mass emission indices (EIs) in the range of 20 to 700 mg/kg fuel and PM number EIs ranging from 0.5?×?10¹⁵ to 5?×?10¹⁵ particles/kg fuel depending on engine load and fuel type. In addition, significant reductions in both the SO₂ and PM EIs were observed for the use of the FT fuel. These reductions were on the order of ～90% for SO₂ and particle mass EIs and ～60% for the particle number EI, with similar decreases observed for black carbon. Also, the size of the particles generated by JP-8 combustion are noticeably larger than those emitted by the APU burning the FT fuel with the geometric mean diameters ranging from 20 to 50 nm depending on engine load and fuel type. Finally, both particle-bound sulfate and organics were reduced during FT-2 combustion. The PM sulfate was reduced by nearly 100% due to lack of sulfur in the fuel, with the PM organics reduced by a factor of ～5 as compared with JP-8.

Implications: The results of this research show that APUs can be, depending on the level of fuel usage, an important source of air pollutant emissions at major airports in urban areas. Substantial decreases in emissions can also be achieved through the use of Fischer Tropsch (FT) fuel. Based on these results, the use of FT fuel could be a viable future control strategy for both gas- and particle-phase air pollutants.     

Semi-automatic reduction and upscaling of large models: A farm management example

Research questions at the regional, national and global scales frequently require the upscaling of existing models. At large scales, simple model aggregation may have a prohibitive computational cost and lead to over-detailed problem representation. Methods that guide model simplification and revision have the potential to support the choice of the appropriate level of detail or heterogeneity within upscaled models. Efficient upscaling will retain only the heterogeneity that contributes to accurate aggregated results. This approach to model revision is challenging, because automatic generation of alternative models is difficult and the set of possible revised models is very large. In the case where simplification alone is considered, there are at least n²−1 possible simplified models where n is the number of model variables. Even with the availability of High Performance Computing, it is not possible to evaluate every possible simplified model if the number of model variables is greater than roughly 35. To address these issues, we propose a method that extends an existing procedure for simplifying and aggregating mechanistic models based on replacing model variables with constants. The method generates simplified models by selectively aggregating existing model variables, retaining existing model structure while reducing the size of the set of possible models and ordering them into a search tree. The tree is then searched selectively. We illustrate the method using a catchment scale optimization model with c. 50,000 variables (Farm-adapt) in the context of adaptation to climatic change. The method was successful in identifying redundant model variables and an adequate model 10% smaller than the original model. We discuss how the procedure can be extended to other large models and compare the method to those proposed by others. We conclude by urging model developers to regard their models as a starting point and to consider the need for alternative models during model development.     

Leading from the front? Social networks in navigating groups

In many group-living animals, leadership by only a fraction of the group members can be important for group navigation. It has been shown that subgroups of informed individuals can steer the remainder of the group without direct communication, resolving conflicts of interest through individual-to-individual interactions. We present a model for the navigation of collectively moving groups that includes preferential interactions between individuals as a way of imposing social network structures, known to be present in many species. We show that effective leadership can occur when leaders do not occupy frontal spatial positions and when navigation tendency is appropriately balanced with social position. Our model also shows that small minorities can dominate movement decisions if they have navigational knowledge combined with influential social network positions. Our findings highlight the mechanistic importance of social networks for the movement decisions of animal groups. We discuss the implications of our research for interpreting empirical observations.     

Ammonia,methane, and nitrous oxide emission from pig slurry applied to a pasture in New Zealand

Much animal manure is being applied to small land areas close to animal confinements, resulting in environmental degradation. This paper reports a study on the emissions of ammonia (NH3), methane (CH4), and nitrous oxide (N2O) from a pasture during a 90-d period after pig slurry application (60 m3 ha-1) to the soil surface. The pig slurry contained 6.1 kg total N m-3, 4.2 kg of total ammoniacal nitrogen (TAN = NH3 + NH4) m-3, and 22.1 kg C m-3, and had a pH of 8.14. Ammonia was lost at a fast rate immediately after slurry application (4.7 kg N ha-1 h-1), when the pH and TAN concentration of the surface soil were high, but the loss rate declined quickly thereafter. Total NH3 losses from the treated pasture were 57 kg N ha-1 (22.5% of the TAN applied). Methane emission was highest (39.6 g C ha-1 h-1) immediately after application, as dissolved CH4 was released from the slurry. Emissions then continued at a low rate for approximately 7 d, presumably due to metabolism of volatile fatty acids in the anaerobic slurry-treated soil. The net CH4 emission was 1052 g C ha-1 (0.08% of the carbon applied). Nitrous oxide emission was low for the first 14 d after slurry application, then showed emission peaks of 7.5 g N ha-1 h-1 on Day 25 and 15.8 g N ha-1 h-1 on Day 67, and decline depending on rainfall and nitrate (NO3) concentrations. Emission finally reached background levels after approximately 90 d. Nitrous oxide emission was 7.6 kg N ha-1 (2.1% of the N applied). It is apparent that of the two major greenhouse gases measured in this study, N2O is by far the more important tropospheric pollutant.     

The impact of environmental assessment on local planning authorities

Studies of two samples of 24 selected local planning authorities (LPAs) in the UK were undertaken to determine the effect of environmental assessment (EA) regulations on planning practice during their first 18 months of operation. EA has been integrated into the UK planning system without significant recourse to the courts and many LPAs regarded EA as a worthwhile and helpful procedure. However, several LPAs did not consider whether to request EA for projects that might be likely to have significant impacts and some LPAs did not follow statutory and recommended consultation procedures. LPAs did not evaluate environmental statements systematically and their quality was often unsatisfactory. However, mitigation of environmental impacts took place in many cases though two‐fifths of the 20 determined applications involving EA were refused. Half the decisions took longer than the 16‐week time limit. While practice is evolving as experience is gained, there is obvious scope for further improvement and suggestions are made to enhance the contribution of EA to the planning system.