Investigation of hydrogeologic processes in a dipping layer structure: 2. Transport and biodegradation of organics

Numerical simulation tools have been used to study the dominating processes during transport of aromatic hydrocarbons in the unsaturated soil zone. Simulations were based on field observations at an experimental site located on a glacial delta plain with pronounced layered sedimentary structures. A numerical model for transport in the unsaturated zone, SWMS-3D, has been extended to incorporate coupled multispecies transport, microbial degradation following Monod kinetics and gas diffusive transport of oxygen and hydrocarbons. The flow field parameters were derived from previous work using nonreactive tracers. Breakthrough curves (BTC) from the hydrocarbon field experiment were used to determine sorption parameters and Monod kinetic parameters using a fitting procedure. The numerical simulations revealed that the assumption of homogeneous layers resulted in deviations from the field observations. The deviations were more pronounced with incorporation of reactive transport, compared with earlier work on nonreactive transport. To be able to model reasonable BTC, sorption had to be reduced compared to laboratory experiments. The initial biomass and the maximum utilisation rate could be adjusted to capture both the initial lag phase and the overall degradation rate. Nevertheless, local oxygen limitation is predicted by the model, which was not observed in the field experiment. Incorporation of evaporation and diffusive gas transport of the hydrocarbons did not significantly change the local oxygen demand. The main cause of the observed discrepancies between model and field are attributed to channelling as a result of small-scale heterogeneities such as biopores.     

Prey size selection,feeding rates and growth dynamics of heterotrophic dinoflagellates with special emphasis on Gyrodinium spirale

The relationship between size and growth rate in heterotrophic dinoflagellates (collected from the Kattegat, Denmark during 1989 and 1990) was studied. In addition, prey size selection, feeding rates and growth dynamics were studied for the naked heterotrophic dinoflagellate Gyrodinium spirale Bergh. Heterotrophic dinoflagellates have growth rates which are approximately three times lower than that of their potential competitors, the ciliates. G. spirale requires a relatively high prey concentration in order to grow. Ingestion rate at the maintenance level is about half of that of maximum ingestion rate. Consequently, yield is lower than typically found for planktonic protozoa. When exposed to low prey concentrations, the dinoflagellate is able to reduce its metabolism and thus prolong survival. The optimum prey particle size for G. spirale, which feeds by direct engulfment, corresponds to its own size. The ability to ingest relatively large prey may explain why these organisms are competitive in nature.     

High degree of polyandry in Apis dorsata queens detected by DNA microsatellite variability

Workers of six colonies of the giant honeybee Apis dorsata from Sabah, Malaysia (five colonies) and Java (one colony) were genotyped using single locus DNA fingerprinting. The colonies from Sabah nested in colony aggregations of 5 and 28 nests respectively on two trees. Three DNA microsatellite loci (A14, A76, A88) with a total of 27 alleles provided sufficient genetic variability to classify the workers into distinct sub-families revealing the degree of polyandry of the queens. Queens mated on average with 30.17 ± 5.98 drones with a range from 19 to 53. The average effective number of matings per queen was 25.56 ± 11.63. In the total sample of 192 workers, 22 individuals were found that were not offspring of the colony's queen. Three of these were potentially drifted offspring workers from genotyped queens of colonies nesting on the same tree.     

Life cycle assessment and environmental improvement of residential and drinking water supply systems in Hanoi,Vietnam

In many Asian cities the public water supply is characterised by low pressure, frequent interruptions and occasional contamination. Hence, private households have to store water and increase pressure individually to ensure an uninterrupted supply at sufficient pressure and water for drinking has to be boiled or supplied separately in bottles. In this study the present water supply system in Hanoi and a number of modification options were analysed from an environmental point of view through life cycle assessment (LCA) in order to identify the most sustainable solutions for future water supply. It was found that the boiling of water for drinking was the largest source of impacts in the present system. Impacts could be reduced significantly if the public supply network was improved and private pumping and storage could be avoided and if the water could be used directly for drinking. It was also found that impacts could be reduced if consumers used bottled water for drinking instead of boiling tap water. Finally, it was demonstrated that even if drinking water cannot be supplied directly through the public network, a reliable public water supply at high pressure is environmentally advantageous. Sensitivity analyses revealed that the conclusions of this study are likely to be applicable to other cities with similar water supply systems.     

Knowledge Production and Learning for Sustainable Landscapes: Seven Steps Using Social–Ecological Systems as Laboratories

There are multiple challenges regarding use and governance of landscapes’ goods, functions and intangible values for ecosystem health and human well-being. One group of challenges is to measure and assess principal sustainability dimensions through performance targets, so stakeholders have transparent information about states and trends. Another group is to develop adaptive governance at multiple levels, and management of larger geographical areas across scales. Addressing these challenges, we present a framework for transdisciplinary research using multiple landscapes as place-based case studies that integrates multiple research disciplines and non-academic actors: (1) identify a suite of landscapes, and for each (2) review landscape history, (3) map stakeholders, use and non-use values, products and land use, (4) analyze institutions, policies and the system of governance, (5) measure ecological, economic, social and cultural sustainability, (6) assess sustainability dimensions and governance, and finally (7) make comparisons and synthesize. Collaboration, communication and dissemination are additional core features. We discuss barriers bridges and bridges for applying this approach.     

Sustained Yield Forestry in Sweden and Russia: How Does it Correspond to Sustainable Forest Management Policy?

This paper analyzes how sustained yield (SY) forestry is defined and implemented in Sweden and Russia, two countries with different forest-industrial regimes. We first compare definitions of SY forestry in national legislation and policies. Then we study forest management planning in two large forest management units with respect to: delivered forest products and values, how the harvest level of timber is defined, where the harvest takes place, and what treatments are used to sustain desired forest products and values. In Sweden SY forestry is maximum yield based on high-input forest management, and in Russia it is forestry based on natural regeneration with minimum investments in silviculture. We conclude that how SY forestry contributes to SFM depends on the context. Finally, we discuss the consequences of SY forestry as performed in Sweden and Russia related to its ability to support diverse forest functions, as envisioned in sustainable forest management policy.     

Simultaneous CO2 injection and water production to optimise aquifer storage capacity

The estimates for geological CO₂ storage capacity worldwide vary, but it is generally believed that the capacity in saline aquifers will be sufficient for the amounts of CO₂ that will need to be stored. The effort required to select and qualify a geological storage site for safe storage will, however, be significant and storage capacity may be a limited resource regionally. Both from a economic and resource management perspective it is therefore important that potential storage sites are exploited to their full potential.In static capacity estimates, where the maximum stored amount of CO₂ is given as a fraction of the formation pore volume, typically arrive at efficiency factors in the range of a few per cents. Recent work has shown that when the dynamic behaviour of the injected CO₂ is taken into account, the efficiency factor will be reduced because of the increase in pore pressure in the region around the injection well(s). The increase in pore pressure will propagate much further than the CO₂. The EU directive on geological CO₂ storage specifically addresses the restriction that will apply when different storage sites are interacting due to pressure communication. Consequently, the pore pressure increase at the boundary of the storage license area will be an important limiting factor for the amount of CO₂ that can be injected.One obvious method to control the pore pressure is to produce water from the aquifer at some distance from the CO₂ injection wells. This paper discusses results from simulations of CO₂ injection in two aquifers on the Norwegian Continental Shelf; the Johansen aquifer and the southern part of the Utsira aquifer. These aquifers are candidates for injection of CO₂ shipped out via pipeline from the Norwegian West Coast. The injected amounts of CO₂ over a period of 50 years are 0.518 Gtonne for the Johansen aquifer and 1.04 Gtonne for the Utsira aquifer.Several design options for the injection operations are investigated: Injection of CO₂ without water production; injection into several wells to distribute the injected fluids and reduce the local pressure increase around each injection well; and injection with simultaneous production of water from one or more wells. The boundaries of the aquifer formations are assumed closed in all simulations. The possible consequences of other types of boundary conditions (semi-closed or open) are briefly discussed.     

The role of co-operation between academia and policymakers for the development and use of sustainability indicators – a case from the Finnish Kymenlaakso Region

In this article, we analyze the co-operation between academia and other stakeholders in the development and use of sustainability indicators. The empirical case is a self-assessment of a Life-Environment project, ECOREG (2002–2004), in which eco-efficiency indicators were constructed for the Finnish Kymenlaakso Region. In the article the relationship between academia and local decision-makers in both the ECOREG Project and the activities thereafter is examined. Contrary to many sustainability indicator initiatives the ECOREG indicators have been updated and used after the original project ended. A main conclusion of the article is that the use of the indicators is largely influenced by how they were originally developed. More specifically, that knowledge was jointly produced instead of being merely transferred from academia to policymakers affected the relevance of the indicators as well as the capabilities of local actors to use, update and further develop the indicators.     

University engagement and regional sustainability initiatives: some Danish experiences

With an outset in ‘sustainability’ defined as a continuous process requiring balance between (the emergence of) problems and our ability and capability to solve them using four distinct capitals available, i.e. natural, production, human and intellectual, and social capital, a model of universities as factories is used. The model suggests that the most notable products of a university being graduates, and knowledge in the form of books, journal articles etc., i.e. human and intellectual capital. As a consequence, these are also the most important impacts from a university. Using the case of Aalborg University, Denmark, the linkages (actual, potential and missing) between academic work in research and education and sustainability initiatives are explored. The focus is both on the university's core activities as a provider of research and education and on the university's activities as an organisation, i.e. its own operation and its accounting for this. It is suggested that systematic engagement activities could benefit both the university's ability to manage internal university processes (by learning from its peers) and its ability to produce the right graduates and knowledge. As a consequence, the main societal benefit would be the ability to better cope with emerging problems endangering the sustainable development of our societies. It is concluded that Aalborg University with its long tradition for project-based and problem-oriented learning in fact has every opportunity to be able to lead by example and become the link to sustainability.     

The Magnitude of Local Host Specif icity for Phytophagous Insects and its Implications for Estimates of Global Species Richness

Abstract: Estimates of the global number of arthropod species range from 2 million to more than 30 million species. One of the most critical assumptions affecting the higher of these estimates is the assumed magnitude of host specificity of phytophagous insects, which varies considerably. Difficulties in estimating this value are caused by both lack of satisfactory data sets and lack of methods for its objective calculation. We provide a new method for predicting host specificity for phytophagous insects at a local scale based on the concept of effective specialization. When the insect-plant host associations of a restricted number of plant species are known, we can predict the magnitude of host specificity when more plant species are included. Based on 2561 host observations of 697 beetle species on 50 plant species in the canopies of a tropical dry forest in Panama, we predict that host specificity for adult phytophagous beetles in this forest range from 7% to 10%. These values suggest that the higher estimates of global species richness are not tenable.