Good Quality Sites Research Articles

Patterns in bird and pollinator occupancy and richness in a mosaic of urban office parks across scales and seasons.

Urbanization is a leading cause of global biodiversity loss, yet cities can provide resources required by many species throughout the year. In recognition of this, cities around the world are adopting strategies to increase biodiversity. These efforts would benefit from a robust understanding of how natural and enhanced features in urbanized areas influence various taxa. We explored seasonal and spatial patterns in occupancy and taxonomic richness of birds and pollinators among office parks in Santa Clara County, California, USA, where natural features and commercial landscaping have generated variation in conditions across scales. We surveyed birds and insect pollinators, estimated multi-species occupancy and species richness, and found that spatial scale (local, neighborhood, and landscape scale), season, and urban sensitivity were all important for understanding how communities occupied sites. Features at the landscape (distance to streams or baylands) and local scale (tree canopy, shrub, or impervious cover) were the strongest predictors of avian occupancy in all seasons. Pollinator richness was influenced by local tree canopy and impervious cover in spring, and distance to baylands in early and late summer. We then predicted the relative contributions of different spatial scales to annual bird species richness by simulating "good" and "poor" quality sites based on influential covariates returned by the previous models. Shifting from poor to good quality conditions locally increased annual avian richness by up to 6.8 species with no predicted effect on the quality of the neighborhood. Conversely, sites of poor local and neighborhood scale quality in good-quality landscapes were predicted to harbor 11.5 more species than sites of good local- and neighborhood-scale quality in poor-quality landscapes. Finally, more urban-sensitive bird species were gained at good quality sites relative to urban tolerant species, suggesting that urban natural features at the local and landscape scales disproportionately benefited them.

The impact of the Asian chestnut gall wasp (Dryocosmus kuriphilus) on chestnut tree growth may be mediated by site resources

IntroductionThe Asian chestnut gall wasp (Dryocosmus kuriphilus) is a major pest of chestnut trees worldwide, seriously affecting chestnut cultivation. Information concerning the effects of gall wasp attack on diameter growth of chestnut trees is currently scarce and limited to coppice stands and to use of the growth of a non-target control species (unaffected by the pest) for reference purposes. The effects of the pest on widely-spaced plantations (grown at a much lower density than chestnut coppices) and the use of explicitly-observed annual infestation rate data remain to be explored.MethodsIn the present study, we analyzed the impact of the chestnut gall wasp on the diameter growth of chestnut trees, using data from 16 experimental plots established in widely-spaced plantations located in good quality sites. Two of the plots are in plantations where a susceptible hybrid chestnut clone and a chestnut clone resistant to the gall wasp coexist, whereas the remaining 14 plots are in Castanea sativa plantations where the level of gall wasp infestation varies across trees and years. The plots were surveyed to determine the diameter growth of the trees and the level of infestation during 5 years (2017–2021).ResultsThe infestation level corresponding to the theoretical damage threshold was surpassed inmost plots during the study period. Nevertheless, there were no differences in the growth of attacked and unaffected plants in the two plots planted with hybrid clones with contrasting susceptibility to the gall wasp. The attack had a modest effect in C. sativa plots, with a mean reduction in annual basal area increment of 9.9%.DiscussionThese findings apparently contradict previous reports of a marked reduction in radial growth of chestnut coppice trees due to gall wasp attack. The difference in findings may be related to increased compensation for herbivory with increasing levels of resources (especially light) in the plantations under study, which were less dense than previously studied stands. The study outcomes add to existing knowledge on the impact of chestnut gall wasp on wood formation and may have implications regarding planting site recommendations and subsequent stand management.

Factors affecting winter damage and recovery of newly planted Norway spruce seedlings in boreal forests

In boreal and temperate forest zones, snowless winters and springs with varying temperature conditions are becoming more common with climate change. In the spring of 2020, extensive winter damage in Norway spruce (Picea abies (L.) Karst.) seedlings, which had been planted the previous year in Central Finland, was observed. In most cases, the probable reason was winter desiccation. This provided a good opportunity to study the regeneration site, seedling, and weather factors that affect winter damage and the recovery of seedlings from damage. In the study, systematic plot sampling was done in 60 selected regeneration sites where damage was known to have occurred. The prediction models for the probabilities of winter damage and the recovery of seedlings were fit to the data. The risk of winter damage was higher in seedlings packed in a closed package than in seedlings stored in open trays. The risk was especially high if seedlings packed in a closed package were stored for more than a week before planting in the middle of June or later. In open trays, the risk of damage was highest in seedlings planted in September, but even then, the risk was lower than in seedlings packed in a closed package. Long storage duration also increased the damage risk in seedlings stored in open trays and planted in September. Other factors that increased damage were coarse soil and the sample plot being on top of a hill. Factors reducing the risk were a fast chain from clear-cutting to planting, planting in good-quality mounds, a sample plot position on the north slope, and the shading of the forest edge on the southern side of a plot. Recovery of seedlings was weaker when seedlings were stored in a closed package and planted in the fall, in too shallow planting depth, or in humus-covered mounds. Recovery improved when seedlings were planted at a depth of at least 5 cm, or when the coniferous forest edge was on the southern or western side of a plot. Winter damage reduced seedling growth and induced the formation of multiple leaders. In practice, the most important factors to be taken into account were avoiding long storage duration and planting seedlings packed in a closed package after the middle of June. Good-quality site preparation and planting were also important for minimizing the risk of damage and improving recovery.

Variations in Benthic Macroinvertebrate Communities and Biological Quality in the Aguarico and Coca River Basins in the Ecuadorian Amazon

Adequate environmental management in tropical aquatic ecosystems is imperative. Given the lack of knowledge about functional diversity and bioassessment programs, management is missing the needed evidence on pollution and its effect on biodiversity and functional ecology. Therefore, we investigated the composition and distribution of the macroinvertebrate community along two rivers. Specifically, 15 locations were sampled in the Coca and Aguarico Rivers (Ecuadorian Amazon) and the macroinvertebrates were used to indicate water quality (WQ), expressed as the Biological Monitoring Working Party Colombia (BMWP-Col) classes. Results indicate that elevation, pH, temperature, width, and water depth played an important role in the taxa and functional feeding groups (FFG) composition. The results show that diversity of taxa and FFG were generally scarce but were more abundant in good quality sites. Collector-gathers (CG) were, in general, dominant and were particularly abundant at low WQ and downstream sites. Scrapers (SC) were the second most abundant group, dominating mostly at good WQ and upstream sites. Predators (PR) were homogeneously distributed among the sites, without clear dominance, and their abundance was slightly higher in sites with medium-low WQ and downstream sites. Lastly, both shredders (SH) and collector-filterers (CF) were almost absent and were more abundant in good quality sites. The findings of this research can be used as baseline information in the studied region since a dam was constructed two years after the sampling campaign, which has been operating since. Furthermore, the results can be used to fill the knowledge gaps related to the bioassessments of other similar systems, particularly for a tropical rainforest.

Fluxes, stocks and availability of nitrogen in evergreen broadleaf and fir forests: similarities and differences

In this study, nitrogen fluxes or flows in litterfall, nitrogen stocks and available nitrogen in soils of two plots representing evergreen broadleaf and Bulgarian fir forests were assessed. Both plots are in good quality sites and for this reason, the litterfall quantities and nitrogen fluxes were relatively high. The woody litterfall flux of nitrogen was significantly higher in the fir forest than in the evergreen broadleaf one. The total nitrogen stock was higher in the soil under the fir forest. However, the percentage of the available nitrogen (ammonium + nitrates) was significantly higher in the upper 20 cm soil layer of the evergreen broadleaf forest in spite of the higher average C/N ratios in the foliar litterfall of the broadleaf forest and insignificant difference of the C/N ratios in all soil layers of the two ecosystems. The microclimatic conditions (higher soil temperatures in the evergreen broadleaf forest) is probable possible cause for this difference. The available nitrogen in the soils and its retranslocation from senescing leaves cover the nitrogen requirements of trees. It is hypothesized that trees may also take up nitrogen from deeper soil layers.

Larval competition risk shapes male–male competition and mating behavior in an anuran

Mate preference was long assumed to be static and open-ended. However, a growing body of evidence actually suggests that the predominant factor in mate choice fluctuates due to the context dependence of the factors involved in sexual selection. In particular, fluctuation in the local environment, the density of individuals, and the presence of heterospecifics can all alter the strength, form, or direction of sexual selection by shaping the fitness costs and benefits of the traits that mediate male–female interactions. Amphibians constitute useful biological models to examine context dependence in sexual selection as the availability of suitable breeding resources may significantly impact the cost–benefit trade-off between mating strategies. Using an experimental approach, we examined how the risk of larval competition in breeding ponds affects pond occupancy, male–male spacing behavior, and spawning decisions in an anuran, the yellow-bellied toad (Bombina variegata). Then, we examined how female mate choice is affected by male body condition and how the risk of larval competition might influence females when choosing a mate. Our results indicate that male pond preference is strongly affected by the presence of conspecific tadpoles. Males preferentially selected ponds free of tadpoles, and spawning mainly occurred in these same ponds. This preference influenced male spacing behavior by enhancing the proximity of competing males when the availability of good-quality sites was experimentally manipulated, which had further significant consequences on females’ choice of mate. The article also discusses the evolutionary causes and consequences of such context-dependent mate choice in amphibians and beyond.

Carbon Sequestration of Caesalpinia platyloba S. Watt (Leguminosae) (Lott 1985) in the Tropical Deciduous Forest.

Caesalpinia platyloba was evaluated as an alternative for the retention of atmospheric carbon and as a feasible and viable economic activity in terms of income for tropical deciduous forest (TDF) peasants in the carbon markets. A total of 110 trees of C. platyloba from plantations and a TDF in the Northwest of Mexico were sampled. Growth (increase in height, diameter, and volume curves) was adjusted to assess their growth. Growth of individuals (height, diameter at breast height [DBH], age, and tree crown cover) was recorded. The Schumacher model (H = β 0 e β1•E-1), by means of the guided curve method, was used to adjust growth models. Information analysis was made through the non-linear procedure with the multivariate secant or false position (DUD) method using the SAS software. Growth and increase models revealed acceptable adjustments (pseudo R2>0.8). C. platyloba reaches >8m of height with 12cm in diameter and 550cm3 of volume, presenting the highest increase at 11 years considered as basal age. Highest significant density of wood was in good quality sites (0.80g•cm-3), with a carbon content (average of 99.15tC•ha-1) at the highest density of 2500 trees•ha-1 (without thinning). Average incomes of US$483.33tC•ha-1 are expected. The profitability values (NPW = US$81,646.65, IRR = 472%, and B/C = 0.82) for C. platyloba make its cultivation a viable and profitable activity, considering a management scheme of the income derived from wood selling and from carbon credits.

Growth and productivity of New Zealand kauri (Agathis australis (D.Don) Lindl.) in planted forests

BackgroundThe establishment of even-aged planted stands of New Zealand kauri (Agathis australis (D.Don) Lindl.) for timber has been constrained by a lack of quantitative information on productivity and rotation length on which forest management and investment decisions could be made.MethodsStand-level models of height and basal area against time were developed (as well as a stand-volume function to calculate volume from height and basal area) based on planted stands that were up to 83-years old and represented planting sites both within and outside the current natural range of the species.ResultsPlanted kauri was shown to be slow to establish with little height growth for the first five years after planting. Similar trends were observed for basal area and whole-tree volume development. A Schumacher equation with local slope parameter and asymptote bounded at 45 m gave the best fit for height, while a von Bertalanffy-Richards equation in difference form with local slope parameter gave the best fit for basal area. For plantations with an average site index (20.4), height was predicted to be 22.3 m in height at age 60, with a basal area of 78.1 m2 ha-1. Whole-tree volume was predicted to be 702 m3 ha-1. Predicted volume mean annual increment was 11.7 m3 ha-1 yr-1for all stands at age 60. From age 20-60 years, stands with a higher site index had a volume mean annual increment of 18.6 m3 ha-1 yr-1. The best stand exceeded 20 m3 ha-1 yr-1.ConclusionsThis study indicates an opportunity to grow kauri in plantations on selected good-quality sites over rotations of 60-80 years or less.

Fish Index of Biotic Integrity (FIBI) A New Method of Assessing Water Quality in Sri Lankan River Waters

A multimetric fish Index of Biotic Integrity (FIBI) was used for the assessment of waterquality in Kelani River in Sri Lanka. The original FIBI was developed for streams in theUnited States Midwest streams by James Karr and present fish index was developed bymaking regional modifications to the original IBI to reflect the fish assemblages and structureof the river system in Sri Lanka. The validity of this modified IBI was determined byexamining the quality of river water using Physico-chemical parameters in upper and lowerreaches of the study area.An assessment program was carried out in the two sites in upper reach (Kaduwela) and lowerreach (Thotalanga) of Kelani river basin from January to July 2012. Fish assemblages weresurveyed by gill nets. Once fish samples were collected they have been identified, counted,examined for diseases and anomalies, and several other biometrics are applied to evaluatebiotic integrity.FIBI developed for two sites of the Kelani River is comparable with Water Quality Index(WQI) developed based on selected physico-chemical parameters for the same site. The IBIbased on fish was defined as the average of these 14 metrics after scoring as 1, 3 or 5 by amodified trisection method and five integrity classes were defined. WQI was calculated foreach site based on the results of the tested water quality measurements such as DissolvedOxygen (DO), Biological Oxygen Demand (BOD5), pH from both laboratory and field surveyrecords and determination of the water quality in each site was based on the categorieschosen.Fish IBI scores for these two sites were highly corresponded with the WQI scores obtainedby tested physico-chemical parameters. Kaduwela site (Score = 28) was ranked as ‘Fair’while the others in Thotanlanga (Score = 40) was ranked as ‘Poor’ for FIBI ranking criteria.By comparing the WQI index, Kaduwela site (57.35) was ranked as ‘Fair’ while Thotanlanga(36.9) was ranked as ‘Poor’. Therefore, in this research project, the developed IBI based onfish clearly showed its potential to assess the water quality of Kelani River while suggestingas a valuable and complementary tool to assess the ecological quality distinguished as goodquality sites from disturbed sites.

Managing drought-induced mortality in Pinus radiata plantations under climate change conditions: A local approach using digital camera data

Pinus radiata D. Don is an internationally important plantation species. The predicted increases in the frequency, duration and/or severity of drought and heat stress associated with climate change could challenge the commercial viability of P. radiata plantations in several countries where existing plantations are grown in districts already vulnerable to periods of drought. We undertook an empirical approach to examine silvicultural and site factors associated with a significant drought-induced mortality event in southern New South Wales, Australia. The aim was to identify local, practical, risk prevention options for P. radiata plantations exposed to the climatic conditions predicted for this region. Our approach did not rely on ground-based assessment of plots but rather a total census of dead trees across two study areas totalling 10,000 ha of P. radiata, in compartments ranging in age from 0 to 35+ years. Dead tree density counts were derived both manually and automatically from high spatial resolution digital multispectral imagery acquired using a Leica ADS40 Airborne Digital Sensor. The results showed a strong correlation between dead tree densities obtained by the manual detection and the automated process ( R = 0.95, P < 0.0001). Two modelling approaches were applied: random forests (RF) and generalised additive models (GAM). For our study sites, both methodologies identified a similar set of parameters, with time since planting in unthinned stands being the most influential variable, and terrain variables playing a smaller role. Specifically, the models identified a threshold age at around 17–18 years for stands on good quality sites and before age 16 on poorer quality sites before the on-set of catastrophic mortality under severe drought conditions. Both modelling techniques also identified similar trends with respect to elevation and slope, and indirectly, site quality. These site attributes being likely to contribute to water availability. If stands in this area are to be planted at 1000 stems ha −1 and thinning schedules cannot be met, then we recommend avoiding sites having a mean elevation of below 600 m or to establish these sites with drought-tolerant genotypes. These recommendations cannot be extrapolated beyond the range of the data. However, the application of robust image classification techniques (e.g. automated tree counts) to high spatial resolution digital imagery, the increasing availability of high resolution climatic, terrain and edaphic GIS datasets, as well as readily available spatial modelling packages, helps off-set the limitations in transferability of our empirical approach.

Environmental Protection in Coastal Recreation Sites in Antalya, Turkey

This study was designed to evaluate different approaches to the protection of the environments of coastal recreation sites in and around Antalya, Turkey. Data was collected by means of a survey of coastal recreation sites and six categories were evaluated: environmental protection, infrastructure facilities, water conservation, energy conservation, waste management, and protection of the natural environment. The results indicated that there was a clear motivation among site managers or authorities for environmental protection (p < .05), infrastructure facilities (p < .001), water conservation (p < .05), energy conservation (p < .05) and the protection of the natural environment (p < .001) but waste management was not accorded a priority. The quality of coastal recreation largely relies on the attractiveness and naturalness of the environment. Although good quality site management largely depends on the awareness and willingness of individual site managers, more proactive approaches toward better environmental protection of recreation sites along the Turkish Mediterranean coast might be effective in improving their sustainable use, particularly in the absence of proper site planning.

Organising a clinical curriculum in rural settings: implementing quality control

Background: There is much current interest in moving medical education programmes from urban teaching hospitals to rural and remote locations. Purpose: To undertake good quality control of medical education delivery at multiple sites with considerable clinical and environmental diversity. Methods: A mixed method approach was used. Five years of action research and constant comparative analysis was used to identify components that contributed to quality delivery and reduced teaching and learning effectiveness. Results: Good quality sites had the following characteristics: 70% of each week as clinical time; a structured clearly articulated disciplinary focussed academic program; a modified problem based learning program; students who learned clinically in pairs, and a generalist rather than specialist focus. Conclusion: Rural teaching and learning is different from that in tertiary based hospitals and the components of quality curriculum delivery in these locations need to be articulated so that others can learn from their success.

Reply to discussion by J. N. Hutchinson on the paper “Property attribution of 3D geological models in the Thames Gateway, London: new ways of visualising geo-scientific information”

We would like to thank Professor John Hutchinson for his contribution of a discussion to our paper and we would like to respond to the comments he raises. The focus of our paper was on the development of new techniques to display, visualise and attribute 3D geological models in urban areas, in this case the Thames Gateway Development Zone in London. The production of such models does indeed require the collation, data-basing and interpretation of large numbers of good quality site investigation boreholes. 3D geological models are then constructed by experienced geologists who are specialists in the geology being studied. Once constructed, the modelled lithostratigraphic units can then be attributed for a number of different characteristics, such as strength, plasticity and porosity. The 3D attributed geological model is not designed with a specific engineering project in mind; instead it should be viewed more as a desk study resource. For example, the 3D attributed model developed for the Thames Gateway Development Zone provides a way of presenting geo-environmental information in a more accessible and understandable form to the wide range of data users working within the Thames Gateway region. Although urban areas are intensively investigated, unforeseen ground conditions are still a major cause of project overspend. One of the reasons for this is that geoenvironmental data is not always readily accessible, as it is held, in the UK, by numerous clients, consultants, and local authorities. There is, therefore, a need for geologists and engineering geologists alike to be able to visualise ground investigation data from a variety of different sources. BGS is working to collect and data-base this wide range of geoscience information, including site investigation data. This information is now being used to produce attributed 3D models such as those described for the Thames Gateway (Royse et al. 2009). Used correctly, these models should reduce ‘‘anomalous ground conditions’’ that still plague developers (De Freitas and Royse 2009). The authors acknowledge the importance of the total engineering approach as advocated by Fookes (1997), Fookes et al. (2000) and Baynes et al. (2005). The total engineering approach is particularly helpful where there is little useful 3D ground information. Baynes et al. (2005) advocate geological and geomorphological mapping of a route corridor early on in the development process, because it is inexpensive when compared to subsurface investigations and more likely to provide relevant information no matter what direction the final configuration takes. However, Baynes et al. (2005) also say that a high level of geological and geomorphological comprehension is not in itself enough. In essence, the value of geological information is not in the possession of it, but in the interpretation and presentation of that data to those that need it most. Furthermore, the delivery format must make the data more accessible, relevant and understandable. In urban areas, the 3D model could be used as a part of the total engineering approach for specific engineering projects. The attributed geological model, in essence, provides a platform from which a variety of data sources such as geological, hydrogeological and geotechnical information may be integrated and visualised together, thereby enabling those engaged in large-scale construction and regeneration projects to access environmental geoscience information. The models inform specialists and non-specialists alike, so they are able to make appropriate judgements and decisions. K. R. Royse (&) D. C. Entwisle British Geological Survey, Kingsley Dunham Centre, Keyworth, Nottingham, UK e-mail: krro@bgs.ac.uk

Patient information about general anaesthesia on the internet

The internet is a frequently consulted source of health information. Using the Google search engine, we searched for patient information about general anaesthesia on the world wide web, using four synonyms of the term in four languages and analysing the top 20 results. Of the 320 search results, 104 (32%) contained relevant information: 36 (45%) with the English (UK); 39 (49%) with the English (US); 13 (16%) with the Swedish; and 16 (20%) with the Finnish search terms (p < 0.001). 'Good' websites, defined as those with a DISCERN rating of 4-5 stars, were found in all languages: 12 with the English (UK); 11 with the English (US); two with the Swedish; and one with the Finnish search terms (p = 0.012). Few good websites showed a reading grade level of < or = 8 that is recommended for consumer health information. Of the good quality sites, 18/22 (82%) remained within the top 20, three months later.

Physicochemical stream bed characteristics and recruitment of the freshwater pearl mussel (Margaritifera margaritifera)

Summary1. The freshwater pearl mussel (Margaritifera margaritifera) is endangered and of conservation importance. We used its survival/mortality during the critical post‐parasitic phase as a biological indicator for the habitat quality of the stream substratum.2. We established and tested biological, physical and chemical methods of assessing the stream bed in 26 streams from seven European countries. We analysed penetration resistance, texture, the concentrations and ratios of C, N, S, P, Fe, Mn in fine material &lt;100 μm, and redox, pH and electric conductivity at the surface and at 5 and 10 cm into the substratum.3. Sites with high stream bed quality (promoting pearl mussel populations with good juvenile recruitment) had coarser and better sorted substrata with significantly lower quantities of fines, and a higher Mn concentration in the fines, than poor quality sites. Redox potential (Eh) at sites without recruitment differed markedly between the free‐flowing water at the surface and at 5 and 10 cm in the bed, whereas no differences were detectable at good quality sites. This was also true of electric conductivity and, to a lesser extent, pH. The stream bed at sites lacking pearl mussel recruitment had a more variable and higher penetration resistance, indicating clogging of the interstitial macropore system by the deposition of mud and compaction of the stream bed.4. Our results show that habitat quality for pearl mussels depends strongly on the exchange between the surface and the interstices, which is governed by physicochemical characteristics of the stream substratum. Combined measurements of penetration resistance, depth gradients of Eh and texture were most suitable for assessing stream bed quality, while water chemistry was insufficient because of the decoupling of interstitial and free‐flowing water at poor quality sites.

Application of a multimetric fish index to assess the environmental condition of South African estuaries

A multimetric fish index, the Estuarine Fish Community Index (EFCI) of Harrison and Whitfield (2004), was applied to data collected for 190 South African estuaries. Estuaries spanned three biogeographic regions and included three distinct estuarine typologies. The EFCI is based on 14 metrics or measures that represent four broad fish community attributes: species diversity and composition, species abundance, nursery function, and trophic integrity. Metric reference conditions and scoring criteria were developed separately for each estuary type within each zoogeographic region. The final EFCI was applied to each estuary by comparing its fish community with the appropriate reference. Index values ranged between 18 (very poor) and 66 (very good). A comparison of the EFCI with independent measures of estuarine condition revealed that the index was able to effectively differentiate between poor and good quality sites. Applying the EFCI to estuaries in which multiple samples were taken also showed that the index is reproducible. The EFCI is both a robust and sensitive method for assessing the ecological condition of estuarine systems; it is also an effective communication tool for converting ecological information into an easily understood format for managers, policy makers, and the general public.

Arrow IFPA Series: Note 6 of 8: Criterion 2: Ecosystem productivity

This extension note is the sixth in a series of eight that describes a set of tools and processes developed to support sustainable forest management (SFM) planning and its pilot application in the Arrow Timber Supply Area (TSA). It describes the criterion and two of the indicators selected to set thresholds and evaluate potential impacts on ecosystem productivity for an SFM scenario for the Lemon Landscape Unit. The note also summarizes the analysis results obtained when an ecosystem-based simulation model (FORECAST) was used to examine the effects of varying rotation length on measures of selected indicators of long-term ecosystem productivity for representative site types.The analysis considered changes in site index, soil organic matter (SOM), and site nitrogen (N) capital on poor-, medium-, and good-quality sites, and evaluated the utility of these measures in assessing and monitoring the effects of different intensities of stand management (as reflected in harvest rotation length) on ecosystem productivity.Shortening the rotation lengths increased losses of SOM and site N. The poor site showed smaller relative changes in both of these measures when compared to the good and medium sites. This suggests that different sustainability thresholds may be warranted for locations with different site qualities. Shortened rotation lengths had little effect on stemwood production (a proxy for site index), but the reduction in SOM and site N capital would likely translate into a decrease in ecosystem resiliency. Both SOM and N capital are important indicators for evaluating the sustainability of site productivity under alternative management practices. The model results highlight the value of using a multi-indicator approach when evaluating the sustainability of site productivity under alternative management practices.

Developing health website quality assessment guidelines for the voluntary sector: outcomes from the Judge Project.

This paper describes the Judge project, the aim of which was to explore the need for health website quality assessment guidelines for the voluntary sector. Such guidelines would enable health consumers to assess the quality of health sites and assist support groups to produce their own good quality sites. The project was a partnership between the Information Management Research Institute, School of Informatics, Northumbria University and Contact a Family. It was supported by the Health Foundation. The views of health consumers and support group members and workers were obtained by focus groups (35 attendees) and questionnaires (55 responses). They were asked questions about quality issues and concerns about Internet health information and any help they needed with judging the quality of health websites. The results supported the need for guidelines. The guidelines were written to reflect the requirements of health consumers and support groups articulated from the focus group and questionnaire data. They were then disseminated via a website. There is a need to improve communication and information exchange between health consumers and professionals and official organizations; publicise support groups to patients and carers; set up local Webs of Trust, linking together voluntary and statutory organizations within a locality. Professionals and official organizations in the public sector should make information provision to patients and health consumers a priority. Information provision should be embedded in the clinical setting via guidelines, protocols and administrative structures. Professionals should be trained in the role of information and how to provide it in appropriate ways. Support groups should use the Judge guidelines to assist them in producing good quality websites. Support groups should promote the Judge guidelines to health consumers, to help them make their own quality judgement about health-information websites.

Ageing and decline of trembling aspen stands in Quebec

The onset of stand decline is a critical stand development characteristic that can affect both harvesting schedule and annual allowable cutting volume. The age at which stand decline begins was assessed in trembling aspen (Populus tremuloides Michx.) stands in the province of Quebec, Canada, by three different methods. The first used a data source consisting of 1081 temporary sample plots from which a segmented regression model was fitted to detect any deviation from the self-thinning line. This type of deviation was observed below densities of 720 stems/ha, which is normally attained around age 60 on good-quality sites. The second used a data source composed of 34 permanent sample plots that allowed us to calculate the age at which the periodic annual increment was equal to zero. The estimated age at which stands began to decline averaged 64 years, but the large variation around this mean was poorly explained by site factors. The third method used a data source consisting of 98 inventory plots. Volume of tree mortality and of wood decay showed an important increase when stand age was around 60. Hence, the results from three independent sources of data converge toward a generalized loss of aspen volume around age 60. However, the prediction of the age at which decline begins in any particular aspen stand is imprecise and requires an on-site measurement of the stand state.

Does post-fire forest management increase tree growth and cone production in Pinus halepensis?

Sapling densities may greatly increase in Pinus halepensis forest stands after fire. This study examines the effects of different post-fire silvicultural treatments on Aleppo pine forests at sites of different quality in Spain: dry (good) (Yeste, Albacete) and semiarid (worse) (Calasparra, Murcia) by monitoring permanent plots from 1999 to 2001. Changes occurring as a consequence of thinning (to a constant density of 1600 trees/ha), full scrubbing and pruning (to one-half to total height) practices were examined measuring diameter and total height of the trees in a 2-year interval. The growth (except on relative diameter increment) of Aleppo pine from Yeste was greater than from Calasparra, probably as a result of its better site quality. Thinning in the good quality site, and thinning plus scrubbing, in the worse quality one, were the treatments that most improved pine growth. Pruning, in contrast should not be carried out in any site, at least under the conditions of this study. The different response in total growth between plots for the same treatment was caused by differences in initial characteristics of the plots: micro-site quality (dominant height by plot) was important in the good quality site, whereas initial density (saplings/ha) was important in the worse quality one. Regarding fructification, treatments that included thinning plus scrubbing improved, 22 months later, the probability of cone production by a factor of 2.07 in relation to control.