Does nitrogen deposition increase forest production? The role of phosphorus

Effects of elevated N deposition on forest aboveground biomass were evaluated using long-term data from N addition experiments and from forest observation plots in Switzerland. N addition experiments with saplings were established both on calcareous and on acidic soils, in 3 plots with Fagus sylvatica and in 4 plots with Picea abies. The treatments were conducted during 15 years and consisted of additions of dry NH₄NO₃ at rates of 0, 10, 20, 40, 80, and 160 kg N ha⁻¹ yr⁻¹. The same tree species were observed in permanent forest observation plots covering the time span between 1984 and 2007, at modeled N deposition rates of 12-46 kg N ha⁻¹ yr⁻¹. Experimental N addition resulted in either no change or in a decreased shoot growth and in a reduced phosphorus concentration in the foliage in all experimental plots. In the forest, a decrease of foliar P concentration was observed between 1984 and 2007, resulting in insufficient concentrations in 71% and 67% of the Fagus and Picea plots, respectively, and in an increasing N:P ratio in Fagus. Stem increment decreased during the observation period even if corrected for age. Forest observations suggest an increasing P limitation in Swiss forests especially in Fagus which is accompanied by a growth decrease whereas the N addition experiments support the hypothesis that elevated N deposition is an important cause for this development.     

Influence of a heavy rainfall event on the leaching of [14C]isoproturon and its degradation products in outdoor lysimeters

In four different agricultural soils the long-term leaching behaviour of [14C]isoproturon was studied in outdoor lysimeters (2 m length, 1 m2 surface area). The herbicide was applied in spring 1997 and spring 2001. At the end of the first 4-year-investigation period between 0.13% and 0.31% of the applied radioactivity was leached. Isoproturon or known metabolites could not be detected in the leachate. However, shortly after the second application isoproturon and its degradation products 2-hydroxy-isoproturon and monodemethyl-isoproturon were leached via preferential flow in one of the lysimeters (Mollic gleysol) in concentrations of 4.5 microg L-1, 3.1 microg L-1 and 0.9 microg L-1, respectively, thus considerably exceeding the EU threshold limit of 0.1 microg L-1 for ground and drinking water. The results indicate that in soils where mass flow transfer dominates, leaching of isoproturon to groundwater is of low probability whereas in highly structured soils which have the tendency to form macropores, isoproturon can be transported via preferential flow to the groundwater.     

Routinization,work characteristics and their relationships with creative and proactive behaviors

Researchers have claimed that routinization hinders creativity. However, empirical evidence for this assumption is sparse. In this study, we argue that routinization may be beneficial for creativity and related behavior due to available resources that can be used to develop new ideas while working. We examine the relationship between routinization and four work characteristics (job control, job complexity, time pressure, and supervisor support) on the one hand and a range of creative and proactive behaviors on the other hand in a randomly selected sample of 278 employees of a German high‐tech company. Regression analyses reveal that in addition to work characteristics, routinization is generally positively related to creative and proactive behaviors. Ways to enhance routinization and thereby creative and proactive behaviors are discussed. Copyright © 2006 John Wiley & Sons, Ltd.     

GIS‐BASED WATER QUALITY MODELING IN THE SANDUSKY WATERSHED,OHIO, USA1

ABSTRACT: This study focused on the Sandusky Watershed (SW) in Ohio, located within the Great Lakes Basin, with emphasis on two of its subwatersheds, namely Honey Creek (HC) and Rock Creek (RC). The goal was to assess the capabilities of the Soil and Water Assessment Tool (SWAT) to simulate suspended sediment (SS), phosphorus (P) and nitrogen (N) yield in the SW that contribute major sediment and nutrient loads into Lake Erie. The model was calibrated using water flow and water quality parameters for water years 1998 to 1999 and validated model simulations covering the period of water years 2000 to 2001 for monthly conditions. The validation of SS showed correlation coefficients of 0.29 (SW), 0.75 (HC) and 0.69 (RC). Correlation coefficients for P were 0.68 (SW), 0.78 (HC) and 0.37 (RC); for N0₂‐N 0.84 (HC) and 0.38 (RC); for N0₃‐N 0.27 (HC) and 0.76 (RC); for NH₃‐N 0.57 (SW), 0.49 (HC), and 0.13 (RC). In addition, mean errors, root mean square errors, Nash‐Sutcliffe coefficients, and graphs were used to compare simulated to measured data. Simulation success was variable with poor and good simulations, but in most cases, simulated water quality values followed the trend of measured data except for extreme (or intense) rainfall/runoff events. Reviews of 17 applications indicated that the SWAT is suitable for long term continuous simulations but not for storm events. A spatially distributed modeling approach generated maps showing the spatial distribution of SS, P, and N for each simulation element across the Sandusky Watershed.     

A prospective cytogenetic study of third-trimester placentae in small-for-date but otherwise normal newborns

Data in the literature suggest that confined placental mosaicism might be associated with intrauterine growth retardation. However, this association may be coincidental and due to bias of ascertainment. We therefore started a prospective study based on the cytogenetic evaluation of placentae derived from growth-retarded newborns. We further minimized possible bias by excluding those small-for-date infants displaying findings which already could explain intrauterine growth retardation (mothers who are smokers, multiple pregnancies, gestosis, dysmorphic infants). In a collection of 71 small-for-gestational age newborns, we did not see a single case of true confined placental mosaicism.     

BFR-governmental testing programme

As a consequence of results from recent studies, indicating increasing concentrations of polybrominated diphenyl ethers (PBDEs) in a wide range of environmental samples, governments have begun to consider the need to restrict the production and use of this compound group. Within the EU, it has been decided to cease production and use of the pentamix PBDE formulation, and the industry has already moved to alternative compounds. In Asia, the Japanese industries restrict voluntarily the production and use of polybrominated biphenyls (PBBs), hexabromodiphenyl ether and tetrabromodiphenyl ether. In North America, no such decisions have been taken as yet, and production of the pentamix continues. Ecolabelling and ecological product declarations are also being used in order to accelerate the phase-out process of brominated flame retardant (BFR). They restrict to different degrees the use of BFR in plastic, textiles, flexible floorings and insulating materials. Many governments have also initiated studies intended to provide more information on the octamix and decamix PBDE formulations, and the replacement compounds hexabromocyclododecane (HBCD) and tetrabromobisphenol A (TBBPA), regarding their significance as environmental contaminants and to inform the need for further regulatory action. These studies are summarised below.     

Regulation for environmental protection: The Nanticoke industrial complex,Ontario, Canada

This assessment of the environmental protection regulatory system for the $2.2 billion iron and steel plant, oil refinery, and thermal generating station composing the core of the greenfield Nanticoke industrial complex is based upon: the use of governmental and industrial research in project management; technology and institutional arrangements for environmental protection; evidence of environmental changes to date; analysis of government and industrial approval files; and interviews with government, industry, and interest group representatives. Planning, regulation, and management have been reasonably efficient and effective to the beginning of the operational stage for all three major industries as of spring 1980. Of major future concern, however, is management of the cumulative and synergistic impacts of the industries and associated development on air quality as well as the lands, waters, and sensitive ecosystems of the nearby Lake Erie coast. Continuous monitoring, more comprehensive research, and better overall coordination of government, industrial, and public interests are required if Nanticoke benefits are to be achieved without undue cost to pre-project resource users within and outside the Haldimand-Norfolk region.     

Reflexive governance: exploring the concept and assessing its critical potential for sustainable development. Introduction to the special issue

ABSTRACT

Elaborated in publications on transition management, sustainability governance and deliberative environmental governance, ‘reflexive governance’ addresses concerns about social-ecological vulnerabilities, flawed conceptualisations of human-nature relations fragmented governance regimes and conditions for a sustainability transition. Key barriers to reflexive government include unavoidable politics; the influence of broader discursive systems that shape actors’ strategic interests; and structural and deliberate limitations to the range of admitted epistemological understandings, normative perspectives and material practices. Against this background, the contributions to the special issue provide novel conceptual linkages between reflexive governance and boundary objects, intercultural dialogue, conflict management heuristics, discourse linguistics, theories of the policy cycle and reflexive law, network and learning theories, and Lasswell’s ‘developmental constructs’. Based on the contributions, we identify five inherent conceptual tensions of reflexive governance: between the openness of horizontal learning processes and the desired direction towards sustainable development; between reflexive governance as a normative or procedural concept; between expected learning orientations and other, strategic orientations; between governance as a precondition for reflexivity and reflexive learning as a precondition for reorganized governance structures; and between reflexivity as an open-ended, evolutionary process and the need to strategically defend the space for reflexivity against powerful groups with an interest in the status quo.