Contemporary Public Involvement: Toward a strategic approach

Many planning agencies and stakeholder groups experimented with innovative forms of public involvement in the 1990s. British Columbia is one such jurisdiction which embraced the concept of public involvement in a broad range of land and resource management planning scales - to the degree of collaborative planning with communities, using consensus. The purpose of this paper is to present lessons for planners, supported by literature and by research in British Columbia, Canada from 1995-97, on these public involvement processes. Building on earlier 'typologies' for public involvement in planning, it proposes a strategic approach for identifying and analysing stakeholders, for setting objectives and for subsequently choosing the most appropriate level of public involvement.     

Toward an ecological classification of soil bacteria

Although researchers have begun cataloging the incredible diversity of bacteria found in soil, we are largely unable to interpret this information in an ecological context, including which groups of bacteria are most abundant in different soils and why. With this study, we examined how the abundances of major soil bacterial phyla correspond to the biotic and abiotic characteristics of the soil environment to determine if they can be divided into ecologically meaningful categories. To do this, we collected 71 unique soil samples from a wide range of ecosystems across North America and looked for relationships between soil properties and the relative abundances of six dominant bacterial phyla (Acidobacteria, Bacteroidetes, Firmicutes, Actinobacteria, alpha-Proteobacteria, and the beta-Proteobacteria). Of the soil properties measured, net carbon (C) mineralization rate (an index of C availability) was the best predictor of phylum-level abundances. There was a negative correlation between Acidobacteria abundance and C mineralization rates (r2 = 0.26, P < 0.001), while the abundances of beta-Proteobacteria and Bacteroidetes were positively correlated with C mineralization rates (r2 = 0.35, P < 0.001 and r2 = 0.34, P < 0.001, respectively). These patterns were explored further using both experimental and meta-analytical approaches. We amended soil cores from a specific site with varying levels of sucrose over a 12-month period to maintain a gradient of elevated C availabilities. This experiment confirmed our survey results: there was a negative relationship between C amendment level and the abundance of Acidobacteria (r2 = 0.42, P < 0.01) and a positive relationship for both Bacteroidetes and beta-Proteobacteria (r2 = 0.38 and 0.70, respectively; P < 0.01 for each). Further support for a relationship between the relative abundances of these bacterial phyla and C availability was garnered from an analysis of published bacterial clone libraries from bulk and rhizosphere soils. Together our survey, experimental, and meta-analytical results suggest that certain bacterial phyla can be differentiated into copiotrophic and oligotrophic categories that correspond to the r- and K-selected categories used to describe the ecological attributes of plants and animals. By applying the copiotroph-oligotroph concept to soil microorganisms we can make specific predictions about the ecological attributes of various bacterial taxa and better understand the structure and function of soil bacterial communities.     

Mobility of polychlorinated aromatic compounds in soils contaminated with wood-preserving oil

Greater understanding of the mobility of polychlorinated aromatic compounds in soils is needed to investigate contamination and design suitable remediation strategies for sites contaminated with wood-preserving oil. The objectives of this study were (1) to develop a suitable aqueous batch extraction method for soil containing wood-preservative residues; (2) to determine partition coefficients for the primary contaminants [pentachlorophenol (PCP), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFS)] in oil, soil, and aqueous phases; and (3) to evaluate the potential soil migration of the primary contaminants. In a three-phase oil-soil-water mixture, PCP, PCDDs, and PCDFs were partitioned to the greatest extent in the oil phase. These results suggest that the migration of contaminants can occur in a saturated subsurface soil zone containing an oil phase at a wood-preserving site. In the absence of a free oil phase, PCDDs and PCDFs were highly partitioned onto soil and were considered non-leachable in the aqueous phase. However, PCP was considered highly leachable from contaminated soil containing only an aqueous liquid phase. Results from this study indicate that removal of any free oil phase present in subsurface soil should have highest priority during the cleanup of contaminated wood-preserving sites.     

An assessment of the risks associated with PCDDs and PCDFs following the application of sewage sludge to agricultural land in the UK

A model has been developed to describe the transfer of PCDDs and PCDFs from sludge-amended soils to the human foodchain. The model is conservative and assumes that all foods consumed by an individual are derived from sludge-amended soils. Predicted concentrations of PCDDs and PCDFs in potatoes, cereals, root vegetables and leafy vegetables were in close agreement with mean concentrations reported in the food survey conducted by MAFF in the UK. Predicted concentrations in milk were well below the Maximum Tolerable Concentration adopted by MAFF. Assuming a half-life of ten years in sludge-amended soils, the maximum estimated incremental daily intake (IDI) predicted by the model following ten applications of sludge to agricultural land was 0.80 pg I-TEQ kg⁻¹ day⁻¹, representing an increase of approximately 45% on current levels of background exposure. For an individual whose diet is solely derived from sludge-amended soils, the total exposure is predicted to be approximately 181 pg I-TEQ day⁻¹ or 2.6 pg I-TEQ kg⁻¹ day⁻¹. This compares with an average background exposure of approximately 2 pg I-TEQ kg⁻¹ day⁻¹, well within the TDI of 10 pg I-TEQ kg⁻¹ day⁻¹ and indicates that the application of sewage sludge to agricultural land under the conditions assumed would not appear to present a significant health risk under the conservative scenarios considered in this assessment.     

A Bird Community Index of Biotic Integrity for the Mid-Atlantic Highlands

We report on the development and preliminary application of a songbird community-based index of biotic integrity. The bird community index (BCI) sorts bird species found at sample sites into a series of values representing the proportional species richness of 20 behavioral and physiological response guilds. Relative proportions of specialist and generalist guilds are used to assign a composite score to each site. Scores from multiple sites indicate the overall biotic integrity of the study area. The BCI is intended to function as a landscape-scale indicator of biotic integrity, integrating conditions across large sample sites containing diverse ecological resources and intensities of human use. We developed the BCI with data from a 1994 pilot study in central Pennsylvania, then applied our preliminary index in 1995 and 1996 to independent samples of sites across the Mid-Atlantic Highlands Assessment area (MAHA). The 1995 and 1996 sample sites were selected using the probability-based sampling design of the Environmental Monitoring and Assessment Program (EMAP), and therefore represent the total land area in MAHA. Our preliminary assessment indicates that MAHA exhibits six categories of biotic integrity, and that more than 40% of the land area supports the two highest biotic integrity categories. Pending BCI refinement and incorporation of landscape and vegetation explanatory variables, the BCI will be included in a suite of indicators designed to provide an assessment of overall ecological condition in MAHA.     

Ecosystem Impacts of Geoengineering: A Review for Developing a Science Plan

Geoengineering methods are intended to reduce climate change, which is already having demonstrable effects on ecosystem structure and functioning in some regions. Two types of geoengineering activities that have been proposed are: carbon dioxide (CO(2)) removal (CDR), which removes CO(2) from the atmosphere, and solar radiation management (SRM, or sunlight reflection methods), which reflects a small percentage of sunlight back into space to offset warming from greenhouse gases (GHGs). Current research suggests that SRM or CDR might diminish the impacts of climate change on ecosystems by reducing changes in temperature and precipitation. However, sudden cessation of SRM would exacerbate the climate effects on ecosystems, and some CDR might interfere with oceanic and terrestrial ecosystem processes. The many risks and uncertainties associated with these new kinds of purposeful perturbations to the Earth system are not well understood and require cautious and comprehensive research.     

Karyotype,phenotype and parental origin in 19 cases of triploidy

The parental origin of triploidy in 19 cases was examined by inheritance of DNA microsatellites and by methylation patterns of SNRPN or PW71 (where parents' blood was unavailable). The fetal and placental morphology on these cases was reviewed. The phenotype of the fetuses with non-mosaic triploidy was assessed in relation to the two types described by McFadden and Kalousek. Of the diandric fetuses three of the six showed mild-to-moderate symmetrical growth retardation and the other three had growth characteristics in accordance with their gestational ages. This study would suggest the fetal triploid ‘Type 1’ definition be modified to ‘well grown to moderate symmetrical IUGR’ to allow for such variation. In the digynic fetuses (McFadden/Kalousek Type 2) there were poor growth characteristics with IUGR being more severe and asymmetrical. The diandric fetuses were as common as digynic fetuses in this series. The ratio of diandric to digynic specimens was 11:8 but if only fetal specimens (not embryos or mosaic children) were included the ratio was 6:5. Many diandric conceptions end as partial moles but later in gestation diandric fetuses may be well grown. It is proposed that there may be a survival barrier for diandric fetuses early in gestation (possibly based on the proportion of vascularised placental villi), although once this is passed the diandric fetuses are comparatively more viable and better grown than digynic fetuses. In the XXY triploid fetuses, 5/6 had hypoplastic or ambiguous external genitalia (two were recorded as of female phenotype) as has been reported previously. In these, the gonadal histology was testicular in all the diandrics but in the single digynic XXY case, sex reversal was complete with normal uterus and Fallopian tubes and the gonads were histologically ovaries. Two triploid/diploid mosaics were proven to be due to digyny. The probable cause is delayed incorporation of the second polar body into a blastomere and there was evidence of identical alleles from the same sperm being present in both diploid and triploid cells. In one of these triploid/diploid mosaics in which there was a termination of pregnancy (TOP) after prenatal karyotyping the diploid cell line had trisomy 16 which was not evident in the triploid line. This trisomy was probably of post-zygotic origin and we suggest the fetus was rescued by the prominence of the triploid line. Copyright © 2001 John Wiley & Sons, Ltd.     

Simulating PM concentration during a winter episode in a subtropical valley: Sensitivity simulations and evaluation methods

We investigated a two-week episode with high PM concentrations in California Central Valley during the Christmas–New Year of 2000–2001 using a modeling system that consists of a computationally efficient, 3-D photochemical–microphysical transport model, a mesoscale meteorological model, emission models, and an evaluation package. One hundred simulations were conducted with fine resolutions and observational constraints, to reproduce spatial and temporal features of observed PM concentrations and to understand the formation mechanism of the episode. Simulated PM concentrations consist of secondary inorganic components, mainly ammonium nitrate, and total carbon in areas with elevated concentrations in the accumulation mode, and consist of mainly dust and sea salt in the coarse mode. Simulated oxidants and nitrate were significantly elevated over the valley, and the latter showed much less amplitude than the former. Simulated PM concentrations were evaluated with observations systematically with spatially and temporally paired method, a more restrictive multivariate method (NMFROC), and a more flexible “gradient evaluation” method. The paired evaluation shows that high correlation coefficient (R = ～0.8) and low fractional error (FE = ～0.1) could be achieved at stations with elevated 24-h concentration of PM in the accumulation mode in some simulations. The NMFROC method was used to extract useful information from seemingly failed simulations. A “gradient evaluation” method is introduced here to extract additional information from simulations. We found that emission reductions of NO_x and AVOC showed similar effects on percentage basis in different areas, and both are more effective than reducing NH₃ for abating elevated concentrations of accumulation mode PM in California Central Valley during the winter episode.     

Nitrogen saturation in stream ecosystems

The concept of nitrogen (N) saturation has organized the assessment of N loading in terrestrial ecosystems. Here we extend the concept to lotic ecosystems by coupling Michaelis-Menten kinetics and nutrient spiraling. We propose a series of saturation response types, which may be used to characterize the proximity of streams to N saturation. We conducted a series of short-term N releases using a tracer (15NO3-N) to measure uptake. Experiments were conducted in streams spanning a gradient of background N concentration. Uptake increased in four of six streams as NO3-N was incrementally elevated, indicating that these streams were not saturated. Uptake generally corresponded to Michaelis-Menten kinetics but deviated from the model in two streams where some other growth-critical factor may have been limiting. Proximity to saturation was correlated to background N concentration but was better predicted by the ratio of dissolved inorganic N (DIN) to soluble reactive phosphorus (SRP), suggesting phosphorus limitation in several high-N streams. Uptake velocity, a reflection of uptake efficiency, declined nonlinearly with increasing N amendment in all streams. At the same time, uptake velocity was highest in the low-N streams. Our conceptual model of N transport, uptake, and uptake efficiency suggests that, while streams may be active sites of N uptake on the landscape, N saturation contributes to nonlinear changes in stream N dynamics that correspond to decreased uptake efficiency.     

Role of multidecadal climate variability in a range extension of pinyon pine

Evidence from woodrat middens and tree rings at Dutch John Mountain (DJM) in northeastern Utah reveal spatiotemporal patterns of pinyon pine (Pinus edulis Engelm.) colonization and expansion in the past millennium. The DJM population, a northern outpost of pinyon, was established by long-distance dispersal (approximately 40 km). Growth of this isolate was markedly episodic and tracked multidecadal variability in precipitation. Initial colonization occurred by AD 1246, but expansion was forestalled by catastrophic drought (1250-1288), which we speculate produced extensive mortality of Utah Juniper (Juniperus osteosperma (Torr.) Little), the dominant tree at DJM for the previous approximately 8700 years. Pinyon then quickly replaced juniper across DJM during a few wet decades (1330-1339 and 1368-1377). Such alternating decadal-scale droughts and pluvial events play a key role in structuring plant communities at the landscape to regional level. These decadal-length precipitation anomalies tend to be regionally coherent and can synchronize physical and biological processes across large areas. Vegetation forecast models must incorporate these temporal and geographic aspects of climate variability to accurately predict the effects of future climate change.