Opportunities and constraints for development and conservation: Teller County/Woodland Park growth management plan

This is the second of three articles prepared to explain the Teller County growth management process. As part of an ongoing growth management process in Teller County, Colorado, opportunities and constraints for development and conservation were identified. The scenic mountain county faces a number of issues because of growth. The recognition of those issues has resulted in the goal to direct future growth to the most appropriate and cost-effective places. To determine those places that are best for new development, thorough ecological inventories were conducted for the entire county as well as for the City of Woodland Park area. From these inventories, environmentally sensitive areas were identified. The environmentally sensitive areas were considered constraints in conducting suitability analyses for a variety of potential land uses. The suitability analyses resulted in the identification of opportunities for future growth in Teller County generally as well as the more specific Woodland Park planning area. This article, like the other two, is part of a reflective analysis by the planners who were involved. Paper 2 in a series 3.     

Modelling C and N mineralization during decomposition of anaerobically digested and composted municipal solid waste.

Application of municipal solid waste (MSW) to arable land can be used to close the nutrient cycle between urban and rural areas. The aim of the current study was to quantify net N mineralization and respiration from composted MSW (CMSW) and anaerobically digested MSW (ADMSW) applied to soil, and to test whether a simple relationship between net N mineralization and respiration that was developed for plant materials, was applicable for these types of MSW. In a laboratory experiment, CMSW and ADMSW were incorporated into soil and incubated at 15 degrees C. During the 149-day experiment, netN mineralization and respiration were determined. Cumulative respiration derived from both MSW types was very steep during the first 30 days, after which it levelled off. However, calculated on the basis of applied C, the ADMSW was 10 times more degradable than the CMSW. Both MSW types caused initial net N immobilization followed by re-mineralization. A simple model based on the relationship between net N mineralization and respiration was only applicable for the MSW after significant modifications. If farmers are to recognize CMSW and ADMSW as valuable fertilizers, it is important that they can be produced with higher maturity, in order to avoid initial N immobilization.     

Urban atmospheric pollution: personal exposure versus fixed monitoring station measurements

We initiated the PETER (pedestrian environmental traffic pollutant exposure research) project to investigate pedestrians' exposure to traffic related atmospheric pollutants, based on data obtained with the collaboration of selected categories of pedestrian urban workers. We investigated relations between roadside personal exposure levels of volatile aromatic hydrocarbons (including benzene) and particulate matter <10 microm (PM10) among traffic police (n = 126) and parking wardens (n = 50) working in downtown Bologna, Italy. Data were collected from workshifts throughout four 1-week periods in different seasons of 2000-2001. For benzene and PM10, comparisons were made with measurements by fixed monitoring stations, and influence of localized traffic intensity and meteorological parameters was examined. Roadside personal exposure to benzene correlated more strongly with other volatile aromatic hydrocarbons (toluene, xylenes and ethylbenzene) than with PM10. Benzene and PM10 personal exposure levels were higher than fixed monitoring station values (both p<0.0001). At multivariate analysis, benzene and PM10 data from fixed monitoring stations both correlated with meteorological variables, and were also influenced by localized traffic intensity. Plausibly because of the downtown canyon-like streets, weather conditions (during a period of drought) only marginally affected benzene personal exposure, and moderately affected PM10 personal exposure. These findings reinforce the concept that urban atmospheric pollution data from fixed air monitoring stations cannot automatically be taken as indications of roadside exposures.     

Diving costs and benefits during post-breeding movements of the Mediterranean shag in the North Adriatic Sea

From the 1980s, Mediterranean shags Phalacrocorax aristotelis desmarestii have become regular summer visitors in the Gulf of Trieste (N-E Italy), as post-breeding movements from Croatian breeding colonies. To characterize such a recent habit and to explore diving optimality models, we investigate foraging strategies and diving patterns at different depths, during breeding and post-breeding seasons. Behavioural data were cross-checked with the species’ diet. Shags foraged on and close to the sea bed, with a prevalent anticipatory breathing strategy. In the Gulf of Trieste, the shallow depths and low mobility of prey allowed shags to use just the oxygen of the respiratory tract, reducing the physiological stress for diving. In Croatia, dive costs increased with depth and prey mobility, resulting in a higher oxygen expenditure that involved also respiratory stores. Such ecological and physiological aspects characterize the Gulf of Trieste as an optimal area for feeding and restoring from the costs of breeding season incurred in Croatia and could be the basis of these post-breeding movements.     

A system dynamics perspective on a viable systems approach definition for sustainable value

Aim of this work is to shed light on sustainable value and develop a model, based on vSa and translated at applicative level through the system dynamics methodology for measuring sustainable value. By adopting vSa perspective, value, characterized by strongly subjective contents, will be considered as a vector quantity, as the result of the subjective weighting of the different dimensions that may change according to the considered organization. Starting from the analysis of system dynamics and vSa, we will implement the theoretical framework into a model developed with system dynamics, hence through a methodology capable of addressing systemic problems which is also an expressive approach to solve issues arising in complex systems (characterized by interdependence, mutual interaction, information feedback, circular causality). In order to translate theory into “action and application” we will develop a model through which it will be possible to exploit the advantages of vSa implemented into an SD model, which ultimately can also be instantiated to specific cases and then simulated for further quantitative insights. Currently, there is no theoretical/practical approach to sustainable value measurement for business organizations that simultaneously considers the dimensions of the triple bottom line together with the subjective perspective of decision-makers. From these considerations, we derived the idea to integrate vSa and system dynamics with the aim of analyzing the issue of sustainable value, whose triple dimension is usually (erroneously) seen under a perspective that does not consider the interactions among those three dimensions. The integration of the subjective perspective within a model for calculating sustainable value can be seen as considering vSa as the theoretical framework, and system dynamics as the methodology that allows translating such an approach into a model that can later be simulated. It is also worth mentioning that through the application of the vSa theory to the case of sustainable value, by means of a transcoding approach like the system dynamics one, we are somehow trying to “redefine”, or better “enhance”, the vSa theory itself, by “operationalizing” it.     

Kinetics of the chemical degradation of diuron

The influence of pH and buffer concentration on the chemical degradation of diuron in water has been analysed over a wide temperature range. The process irreversibly gives 3,4-dichloroaniline as the only product containing the phenyl ring. H+, OH- and phosphate buffer are efficient catalysts of the reaction. The rate constant first increases rapidly at low buffer concentrations and then gradually levels off at higher ones. At 40 degrees C and high phosphate concentration (>0.01 M), or in the extreme pH regions, the half-life is approximately 4 months and the activation energy is 127 +/- 2 kJmol(-1).     

Lead and zinc in sediments and biota from Maarmorilik, West Greenland: an assessment of the environmental impact of mining wastes on an Arctic fjord system

Lead and zinc levels in sediments and biota from the fjord system surrounding the lead/zinc mine at Maarmorilik, West Greenland, were investigated to evaluate the impact of waste rock and marine-deposited tailings on the marine biota. Concentrations of metal in the sediment were up to 8,922 +/- 622 microg g(-1) (dry wt.) for lead and 19,351+/- 476 microg g(-1) (dry wt.) for zinc. Levels of lead and zinc were also elevated in a suite of monitor organisms. The feeding modes of the organisms were used to explain the sources of metals to the organisms. After closure of the mine, the concentrations of metals in the upper centimetres of the sediments decreased, and a decreased impact of metals on the brown alga Fucus distichus was observed. However, the metals in the sediments still affect the marine biota in the area.