Real-world vehicle emissions: a summary of the twelfth Coordinating Research Council On-Road Vehicle Emissions Workshop

The Coordinating Research Council (CRC) held its 12th workshop in April 2002, with nearly 90 presentations on the most recent on-road vehicle emissions research. This paper summarizes the presentations from researchers who are engaged in improving understanding of the contribution of mobile sources to air quality. Participants in the workshop discussed mobile source emission models and emission inventories, results from gas- and particle-phase emissions studies from spark-ignition and diesel-powered vehicles (with an emphasis in this workshop on particle emissions), effects of fuels on emissions, evaluation of in-use emissions control programs, and efforts to improve our capabilities in performing on-board emissions measurements, as well as topics for future research.     

Scale and sustainability of marine bioprospecting for pharmaceuticals

Collecting marine organisms for the discovery and development of pharmaceuticals has been perceived variously as sustaining and threatening conservation. Our initial expectations that marine bioprospecting might pose conservation challenges were largely not confirmed. Thousands of marine species have been collected for initial assessment, but usually only in very small amounts. Very few compounds are sufficiently promising to provoke re-collections, where volumes can be much larger. This is where conservation concerns may arise, particularly if the organism is rare, has a restricted distribution, or is targeted in one narrow area. However, industry generally seeks to avoid dependency on small populations, for economic as well as ecological reasons. Alternative supply strategies to wild capture include synthesis and culture. Mandatory collection protocols and environmental impact (stock) assessments are useful routes for management to achieve sustainable use where extraction is desirable. In general, the scanty information available suggests that marine bioprospecting for pharmaceuticals may have minimal impacts on the environment, particularly compared with those created by other pressures.     

Fate of selenium in biofortification of wheat on calcareous soil: an isotopic study

Selenium (Se) biofortification of staple cereal crops can improve the Se nutritional status of populations. A field trial employing an enriched stable isotope of Se (⁷⁷Se) was undertaken over three consecutive cropping seasons in a coarse-textured, calcareous soil in Gilgit-Baltistan, Pakistan. The objectives were to (1) assess the feasibility and efficiency of Se biofortification, (2) determine the fate of residual Se, and (3) assess the consequences for dietary Se intake. Isotopically enriched ⁷⁷Se (⁷⁷Se_Fert) was applied, either as selenate or as selenite, at three levels (0, 10, and 20 g ha^?1) to a wheat crop. Residual ⁷⁷Se_Fert availability was assessed in subsequent crops of maize and wheat without further ⁷⁷Se_Fert addition. Loss of ⁷⁷Se_Fert was c.35% by the first (wheat) harvest, for both selenium species, attributable to the practice of flood irrigation and low adsorption capacity of the soil. No ⁷⁷Se_Fert was detectable in subsequent maize or wheat crops. The remaining ⁷⁷Se_Fert in soil was almost entirely organically bound and diminished with time following a reversible (pseudo-)first-order trend. Thus, repeat applications of Se would be required to adequately biofortify grain each year. In contrast to native soil Se, there was no transfer of ⁷⁷Se_Fert to a recalcitrant form. Grain from control plots would provide only 0.5 µg person^?1 day^?1 of Se. By contrast, a single application of 20 g ha^?1 Se^VI could provide c. 47 µg person^?1 day^?1 Se in wheat, sufficient to avoid deficiency when combined with dietary Se intake from other sources (c. 25 µg day^?1).

     

假如地球上没有人类

假如地球上没有人类据《新科学家》报道,毋庸置疑,人类是地球有史以来最具统治力的生物。仅仅数千年的时间,城市、农田和牧场就侵占了地球陆地超过1／3的面积。据估计,人类现在霸占了地球40％的生产力。人类的连番冲击让地球变得满目疮痍:草原变为耕地,森林夷为平地,地下蓄水层干枯;而核能废料、化学污染、入侵物种、生物灭绝及气候变暖都是人类活动造成的直接恶果。如果可能的话,与人类分享地球的其它生物会毫不犹豫地把我们“踢出”地球。现在,假设它们如愿以偿,地球上65亿人明天一夜之间从地球上消失,被送到遥远的星系接受再教育,那么,地球将会发生怎样的变化?     

Subject Index

Subject Index

Subject Index     

(Not) talking about justice: justice self-recognition and the integration of energy and environmental-social justice into renewable energy siting

Renewable energy often provokes heated debate on climate change, energy security and the local impacts of developments. However, how far such discussions involve thorough and inclusive debate on the energy and environmental-social justice issues associated with renewable energy siting remains ambiguous, particularly where government agendas prioritise renewable energy and planning systems offer limited opportunities for public debate on value-based arguments for and against renewable energy developments. Using the concept of justice self-recognition, we argue for greater attention to public discussion of the justice dimensions of renewable energy to assist in developing mechanisms to integrate distributive and procedural fairness principles into renewable energy decision-making. To explore how justice is currently invoked in such contexts, we examine recent U.K. policies for renewable energy and public submissions to applications for small-scale wind energy projects in Cornwall, U.K. The analysis of public comments revealed that justice concerns were rarely discussed explicitly. Comments instead did not raise concerns as justice issues or focused implicitly on distributive justice, stressing local aesthetic, community and economic impacts, clean energy and climate change. However, the findings indicated limited discussion of procedural or participatory justice, an absence that hampers the establishment of coherent procedures for deciding acceptable impacts, information standards, public participation and arbitrating disputes. We conclude by suggesting procedural reforms to policy and planning to enable greater public expression of justice concerns and debate on how to negotiate tensions between energy and environmental-social justice in renewable energy siting decisions.     

Local and Indigenous management of climate change risks to archaeological sites

Hundreds of thousands of significant archaeological and cultural heritage sites (cultural sites) along the coasts of every continent are threatened by sea level rise, and many will be destroyed. This wealth of artefacts and monuments testifies to human history, cosmology and identity. While cultural sites are especially important to local and Indigenous communities, a stall in coordinated global action means adaptation at a local scale is often unsupported. In response, this paper produces a practical climate change risk analysis methodology designed for independent, community-scale management of cultural sites. It builds on existing methods that prioritise sites most at risk from climate impacts, proposing a field survey that integrates an assessment of the relative cultural value of sites with assessment of exposure and sensitivity to climate impacts. The field survey also stands as a monitoring program and complements an assessment of organisational adaptive capacity. The preliminary field survey was tested by Indigenous land managers in remote northern Australia at midden and rock art sites threatened by sea level rise, extreme flood events and a range of non-climactic hazards. A participatory action research methodology—incorporating planning workshops, semi-structured interviews and participant observations—gave rise to significant modifications to the preliminary field survey as well as management prioritisation of 120 sites. The field survey is anticipated to have global application, particularly among marginalised and remote Indigenous communities. Well-planned and informed participation, with community control, monitoring and well-informed actions, will contribute significantly to coordinated global and regional adaptation strategies.     

Sustainable Rainwater Catchment Systems for Micronesian Atoll Communities

Atoll island communities rely on rainwater catchment systems (RWCS) as a primary method of storing freshwater. However, stored freshwater can be depleted during times of drought, requiring importation of water to sustain community living. To maintain adequate water supply under future climatic conditions, the functioning of RWCS for atoll communities must be analyzed and optimal designs must be adopted. In this study, a quantitative analysis of stored daily water volumes is provided for atoll islands within the Federated States of Micronesia (FSM), with Nikahlap Island, Pakein Atoll, and a generic island in western FSM used as representative cases. Using a daily water balance model for the RWCS, baseline conditions are simulated for the 1997‐1999 time period, during which an intense El Niño‐induced drought occurred, and a sensitivity analysis is performed to quantify the influence of RWCS features on water system outputs, whereupon an optimal RWCS design using existing infrastructure is analyzed. Results indicate the strong influence of catchment area, system efficiency, and storage capacity on water volumes and the depletion of water during dry seasons and drought periods using current RWCS infrastructure. Adequate storage can be maintained during a major drought if unused RWCS features are employed and if minimal rationing is adopted. Study results provide water resource managers and government officials with valuable data for consideration in water security measures.     

Analyzing the Effects of Groundwater Pumping on an Urban Stream‐Aquifer System

When the cone of influence of a pumping well reaches a nearby river, the resulting hydraulic gradient can induce enhanced seepage of streamflow into the aquifer. The rate of seepage is often modeled using analytical solutions that are simple to apply but may not reproduce field data due to mathematical assumptions not being met in the field. Furthermore, the appropriateness of such models has not been investigated in detail due to difficulty in measuring streamflow loss in the field. In this study, a field experiment was conducted on a reach of the South Platte River near Denver, Colorado to estimate pumping‐induced streamflow loss. A network of stream gauges, monitoring wells, and in situ measurements was used to observe streamflow rates, groundwater levels, and temperature to assess if pumping wells have a significant impact on streamflow, and to compare observed streamflow depletion against analytical solutions. Data collected suggest that pumping wells have a noticeable impact on streamflow. The analytical solutions proved accurate if streamflow was low and constant but performed poorly if streamflow was high and variable. Therefore, for this reach, the use of analytical solutions to predict streamflow may only be appropriate under low‐flow, constant‐flow conditions. Methods and results can be used to guide other streamflow depletion studies and to inform cases of pumping‐induced streamflow depletion, particularly in regard to water rights.