Book reviews

Earth Politics. Ernst Ulrich von Weizsacker, 1994, London, Zed Books, 234 pp. ISBN 1 85649 174 9, pb £14.95; hb £36.95

Greening Your Local Authority. Janice Morphet (Ed.), 1994, London, Pitman Publishing (originally Harlow, Longman), 144 pp. ISBN 0582 229 065, pb £32.50

Ecology and Society: an introduction. Luke Martell, 1994 London, Polity Press, 250 pp. ISBN 0 7456 1022 6, hb £39.50, ISBN 0 7456 1023 4, pb £11.95

The Politics of the Environment. Robert E. Goodin, 1994. Cheltenham, Edward Elgar, 599 pp. ISBN 1 85278 872 0, hb £115.00

Introduction to Environmental Impact Assessment John Glasson, Riki Therivel &; Andrew Chadwick, 1994, London, UCL Press, 352 pp. ISBN 1 85728 117 9, hb £45.00, ISBN 1 85728 118 7, pb £14.95

Planning for the Planet: sustainable development strategies for local and strategic plans. Friends of the Earth, 1994, London, FoE, 104 pp. ISBN 1 85750 224 8, £12.00

Environmental Strategy and Sustainable Development: the corporate challenge for the 21st century. Richard Welford, 1995, London, Routledge, 240 pp. ISBN 0 415 10551 X, hb £40.00, ISBN 0 415 10552 8, pb £12.99

Housing and the Environment: a new agenda. Mark Bhatti, Jane Brooke &; Mike Gibson (Eds), 1994, Foreword by Jonathon Porritt, Coventry, Chartered Institute of Housing, 210 pp. ISBN 0 901 607 738, £14.95     

Estimated effects of climate change on flood vulnerability of U.S. bridges

We assessed the potential impacts of increased river flooding from climate change on bridges in the continental United States. Daily precipitation statistics from four climate models and three greenhouse gas (GHG) emissions scenarios (A2, A1B, and B1) were used to capture a range of potential changes in climate. Using changes in maximum daily precipitation, we estimated changes to the peak flow rates for the 100-year return period for 2,097 watersheds. These estimates were then combined with information from the National Bridge Inventory database to estimate changes to bridge scour vulnerability. The results indicate that there may be significant potential risks to bridges in the United States from increased precipitation intensities. Approximately 129,000 bridges were found to be currently deficient. Tens of thousands to more than 100,000 bridges could be vulnerable to increased river flows. Results by region vary considerably. In general, more bridges in eastern areas are vulnerable than those in western areas. The highest GHG emissions scenarios result in the largest number of bridges being at risk. The costs of adapting vulnerable bridges to avoid increased damage associated with climate change vary from approximately $140 to $250 billion through the 21st century. If these costs were spread out evenly over the century, the annual costs would be several billion dollars. The costs of protecting the bridges against climate change risks could be reduced by approximately 30% if existing deficient bridges are improved with riprap.     

Considering extinction of dependent species during translocation, ex situ conservation, and assisted migration of threatened hosts

Translocation, introduction, reintroduction, and assisted migrations are species conservation strategies that are attracting increasing attention, especially in the face of climate change. However, preventing the extinction of the suite of dependent species whose host species are threatened is seldom considered, and the effects on dependent species of moving threatened hosts are unclear. There is no published guidance on how to decide whether to move species, given this uncertainty. We examined the dependent-host system of 4 disparate taxonomic groups: insects on the feather-leaf banksia (Banksia brownii), montane banksia (B. montana), and Stirling Range beard heath (Leucopogon gnaphalioides); parasites of wild cats; mites and ticks on Duvaucel's gecko (Hoplodactylus duvaucelii) and tuatara (Sphenodon punctatus); and internal coccidian parasites of Cirl Bunting (Emberiza cirlus) and Hihi (Notiomystis cincta). We used these case studies to demonstrate a simple process for use in species- and community-level assessments of efforts to conserve dependents with their hosts. The insects dependent on Stirling Range beard heath and parasites on tigers (Panthera tigris) appeared to represent assemblages that would not be conserved by ex situ host conservation. In contrast, for the cases of dependent species we examined involving a single dependent species (internal parasites of birds and the mite Geckobia naultina on Duvaucel's gecko), ex situ conservation of the host species would also conserve the dependent species. However, moving dependent species with their hosts may be insufficient to maintain viable populations of the dependent species, and additional conservation strategies such as supplementing populations may be needed.     

X-ray absorption spectroscopy studies of reactions of technetium, uranium and neptunium with mackinawite

Technetium, uranium and neptunium may all occur in the environment in more than one oxidation state (IV or VII, IV or VI and IV or V respectively). The surface of mackinawite, the first-formed iron sulfide phase in anoxic conditions, can promote redox changes so a series of laboratory experiments were carried out to explore the interactions of Tc, U and Np with this mineral. The products of reaction were characterised using X-ray absorption spectroscopy. Technetium, added as TcO4(-), is reduced to oxidation state IV and forms a TcS(2)-like species. On oxidation of the mackinawite in air to form goethite, Tc remains in oxidation state IV but in an oxide, rather than a sulfide environment. At low concentrations, uranium forms uranyl surface complexes on oxidised regions of the mackinawite surface but at higher concentrations, the uranium promotes surface oxidation and forms a mixed oxidation state oxide phase. Neptunium is reduced to oxidation IV and forms a surface complex with surface sulfide ions. The remainder of the Np coordination sphere is filled with water molecules or hydroxide ions.     

Climate change and Australia: key vulnerable regions

Natural ecosystems are generally considered to be one of the most vulnerable sectors to negative impacts from rapid climate change. Australia’s rich biodiversity is already under considerable threat from multiple human impacts, and climate change will impose additional stress. Opportunities for most Australian species to adapt to climate change by altering their distribution will be limited due to a number of characteristics of the Australian environment, both physical and biotic, including topography, habitat fragmentation, low capacity for dispersal and the restricted geographic ranges of many species. This review summarizes recent and projected climate trends in Australia and discusses how species may respond to these changes in the context of the particular environmental characteristics and biogeographic history of the continent. It also identifies particular regions and ecosystems likely to be most negatively affected in the short to medium term.     

The effect of pH on plant litter decomposition and metal cycling in wetland mesocosms supplied with mine drainage

The long term effectiveness of compost-based wetland systems treating net-acidic mine waters is reliant upon a continuing supply of decomposed organic matter which provides the basic foodstock for sulphate reducing bacteria. The annual turnover of wetland vegetation within these systems has been suggested to be the primary source for this material once the original substrate has been consumed. This study aimed to determine whether plant litter (of Common Reed, Phragmites australis) decomposition rates and release of metals and nutrients were affected by pH using controlled experiments under laboratory conditions. Loss of plant biomass was found to be unaffected by pH (3.0-6.5) suggesting that plant litter could be an important source of organic molecules for bacterial populations even under acidic conditions. The decomposing plant litter also acted as a focus for the precipitation of Fe oxides and sorption of Zn thereby acting as a short-term sink for these contaminants. This has important implications for geochemical cycling within the wetland system and potential transport out of the system. The essential nutrients (K and Mg) released from plant litter were affected by pH which could be important in nutrient availability for re-use by vegetation and other organisms within the system.     

Characterizing the Relative Contributions of Large Vessels to Total Ocean Noise Fields: A Case Study Using the Gerry E. Studds Stellwagen Bank National Marine Sanctuary

In 2006, we used the U.S. Coast Guard’s Automatic Identification System (AIS) to describe patterns of large commercial ship traffic within a U.S. National Marine Sanctuary located off the coast of Massachusetts. We found that 541 large commercial vessels transited the greater sanctuary 3413 times during the year. Cargo ships, tankers, and tug/tows constituted 78% of the vessels and 82% of the total transits. Cargo ships, tankers, and cruise ships predominantly used the designated Boston Traffic Separation Scheme, while tug/tow traffic was concentrated in the western and northern portions of the sanctuary. We combined AIS data with low-frequency acoustic data from an array of nine autonomous recording units analyzed for 2 months in 2006. Analysis of received sound levels (10–1000 Hz, root-mean-square pressure re 1 μPa ± SE) averaged 119.5 ± 0.3 dB at high-traffic locations. High-traffic locations experienced double the acoustic power of less trafficked locations for the majority of the time period analyzed. Average source level estimates (71–141 Hz, root-mean-square pressure re 1 μPa ± SE) for individual vessels ranged from 158 ± 2 dB (research vessel) to 186 ± 2 dB (oil tanker). Tankers were estimated to contribute 2 times more acoustic power to the region than cargo ships, and more than 100 times more than research vessels. Our results indicate that noise produced by large commercial vessels was at levels and within frequencies that warrant concern among managers regarding the ability of endangered whales to maintain acoustic contact within greater sanctuary waters. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.