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Species of conservation concern are often habitat specialists, posing significant risk to those species when specific plant communities are threatened. As a result, practitioners habitually focus conservation efforts on these communities while ignoring ecological mechanisms that explain the wildlife–plant relationships. In doing so, practitioners may overlook alternative vegetation communities that could maintain wildlife populations under alternative conditions (e.g., climate change). Here, we term these areas surrogate habitat, defined as vegetation communities or resource sites that provide similar critical resources as conventional sites, and assess their potential for conservation using a case study of greater sage‐grouse (Centrocercus urophasianus) on Parker Mountain, Utah (1998–2009). Sage‐grouse are a sagebrush‐obligate species and a species of conservation concern. Range‐wide conservation efforts have long emphasized management of seasonal habitats within semiarid sagebrush ecosystems, specifically management of mesic or wet meadow sites that provide brood‐rearing habitat required for population persistence. Despite this requirement, no conventional mesic habitat exists on Parker Mountain, yet it supports one of Utah's largest sage‐grouse populations. Rather, the Parker sagebrush system abuts quaking aspen (Populus tremuloides) stands that may provide brood‐rearing habitat analogous to wet meadow sites. It is unclear, however, to what extent sage‐grouse use these aspen stands because sage‐grouse commonly avoid tall structures (e.g., trees) and their associated avian predators. Thus, we tested whether (1) sage‐grouse selected for surrogate habitat (i.e., aspen edge) and (2) selection behaviors related to surrogate habitat had demographic effects on the population. As we predicted, sage‐grouse selected for these areas, and the sage‐grouse that spent increased time closer to aspen edges did not experience increased mortality. Together, this demonstrates that the aspen–sagebrush edge provided a surrogate for the wet meadows used by other populations. More broadly, this suggests that conservation practitioners should move beyond simplistic wildlife–habitat associations toward a more holistic view of animal ecology focused on the wildlife–resource association, an approach that becomes particularly useful in areas where conventional obligate habitat may be degraded or lost. This work also implores us to examine alternative habitat potential rather than applying one‐size‐fits‐all models to threatened species conservation. [ABSTRACT FROM AUTHOR]

Quaking aspen (Populus tremuloides Michx.) is being stressed across the America West from a variety of sources including drought, herbivory, fire suppression, development, and past management practices. Rich assemblages of plants and animals that utilize aspen forests, as well as economic values of tourism, grazing, hunting, and water conservation, make aspen ecosystems among the most valuable vegetation types in this region. The 43-ha Pando clone near Fish Lake, Utah, is an iconic example of an aspen community undergoing rapid decline due to overstory mortality and chronic recruitment failure. As part of a larger project to restore Pando, we fenced, treated, and monitored a portion of this famous grove with the intent of documenting regeneration responses and using such practices at larger scales. Twenty-seven randomly stratified monitoring plots were placed across this landscape in order to better understand herbivory and regeneration responses to distinct treatment categories: protected and unprotected, and passive (fenced only) and active (burning, shrub removal, selective overstory cutting) treatments. At each site, we measured basal area and mortality on mature trees, made counts of juvenile and intermediate suckers, documented browse levels and herbivore scat presence, and characterized environmental conditions in terms of aspen and common juniper cover, treatment type, elevation, slope, and aspect. Our results confirmed a positive regeneration response to browsing cessation after fencing, whereas non-fenced areas showed no improvement. Within the fence, there was a significantly better response of active treatment vs. passive and there was no significant difference between treatment types in terms of level of regeneration. Both active and passive management produced regeneration levels that were sufficient to replace dying canopy trees if managers continue to protect suckers until they exceed the reach of browsers. These results support a growing body of research suggesting managers need to invest in continuous protection from herbivory in stable aspen forests, as well as targeting additional post-treatment protection, to ensure adequate regeneration. We examine ramifications of these results for broader restoration purposes in the remainder of Pando, as well as other aspen communities regionally, with the ultimate goal of restoring ecological process toward greater ecosystem resilience. [ABSTRACT FROM AUTHOR]

Late complications affecting Hodgkin lymphoma ( HL) survivors are well described in paediatric and adult-based publications. This study determined the late morbidity and mortality risk for 442 teenage and young adult ( TYAs) 5-year HL survivors, diagnosed at 15-24 years of age between 1970 and 1999, identified from the British Columbia Cancer Registry. Treatment details were abstracted from charts. Survivors and a matched comparison cohort were linked to provincial administrative health datasets until December 2006 and regression analysis was performed, providing risk ratios regarding mortality, secondary malignancy and morbidity causing hospitalisation. Sixty (13·6%) survivors experienced late mortality with excess deaths from secondary cancer [standardised mortality ratio ( SMR) 18·6; 95% confidence interval ( CI) 11-29·4] and non-malignant disease ( SMR 3·6; 95% CI 2·2-5·5). Excess secondary cancers (standardised incidence ratio 7·8; 95% CI 5·6-10·5) were associated with radiotherapy [Hazard ratio ( HR) 2·7; 95% CI 1-7·7] and female gender ( HR 1·8; 95% CI 1-3·4). Of 281 survivors treated between 1981 and 1999, 143 (51%) had morbidity resulting in hospitalisation (relative risk 1·45; 95% CI 1·22-1·73). Hospitalisation significantly increased with combined modality therapy, chemotherapy alone and recent treatment era. TYA HL survivors have excess risk of mortality and secondary malignancy continuing 30 years from diagnosis. Radiotherapy is associated with secondary malignancy and current response-adapted protocols attempt to minimise exposure, but late morbidity causing hospitalisation remains significant. [ABSTRACT FROM AUTHOR]

Question Aspen forests in the northern hemisphere provide richer biodiversity compared to surrounding vegetation types. In both North America and Europe, however, aspen stands are threatened by a variety of human impacts: clear felling, land development, water diversion, fire suppression and both wild and domestic ungulate herbivory. We conducted a landscape assessment of quaking aspen ( Populus tremuloides) for the purpose of identifying key components of resilience. Specifically, we tested novel measures linking plant-animal interactions, compared crucial functional differences in aspen types and made restorative recommendations based on the outcome of these assessments. Location Book Cliffs region, eastern Utah and western Colorado, USA. Methods Seventy-seven 1-ha plots were sampled for forest structure, composition, regeneration and recruitment, landscape elements, browse level and herbivore use. Use was determined by counting the number of pellet groups from ungulate species at each sample location. We tested the efficacy of a visual stand condition rating system when compared to objective metrics. A series of non-parametric analyses were used to compare functional aspen types and stand condition groups by key variables. Non-metric multidimensional scaling ( NMS) allowed us to explore all our data to find the most critical measures of aspen stand conditions for the purpose of better informing future aspen monitoring. Results Plots differed significantly in seral or stable aspen functional types, stand condition rating and browse species use. Ordination analysis revealed that regeneration level and herbivore use were the strongest objective indicators of aspen stand conditions, while stand condition rating proved a valuable subjective index of forest status. While ungulate herbivory of aspen is problematic internationally, our results show acute impacts where moderate slopes, relatively low water availability and intense browsing predominate. Conclusions Appropriate measures for aspen communities, informed by crucial functional divisions, allowed us to gain a clear understanding of conditions across this large landscape. Overall, aspen in our study landscape is highly vulnerable to collapse due to narrow physiographic and climate limitations and browse levels. Without herbivory reduction, future conservation in such areas will be strained and widespread system failure may occur. [ABSTRACT FROM AUTHOR]

The article reports on a study examining inpatient, hospital-related morbidity in a geographically-defined cohort of long-term cancer survivors diagnosed before age 20 years between 1981 and 1995 in the province of British Columbia (BC), Canada. The study found that morbidity was highest for those with previous radiation, chemotherapy, and surgery. It has also been suggested by the study that survivors are at increased ongoing risk of many types of hospital-related late morbidity.

The 7th North American Forest Ecology Workshop, consisting of 149 presentations in 16 oral sessions and a poster session, reflected a broad range of topical areas currently under investigation in forest ecology and management. There was an overarching emphasis on the role of disturbance, both natural and anthropogenic, in the dynamics of forest ecosystems, and the recognition that legacies from past disturbances strongly influence future trajectories. Climate was invoked as a major driver of ecosystem change. An emphasis was placed on application of research findings for predicting system responses to changing forest management initiatives. Several "needs" emerged from the discussions regarding approaches to the study of forest ecosystems, including (1) consideration of variable spatial and temporal scales, (2) long-term monitoring, (3) development of universal databases more encompassing of time and space to facilitate meta-analyses, (4) combining field studies and modeling approaches, (5) standardizing methods of measurement and assessment, (6) guarding against oversimplification or overgeneralization from limited site-specific results, (7) greater emphasis on plant-animal interactions, and (8) better alignment of needs and communication of results between researchers and managers. [ABSTRACT FROM AUTHOR]

Question: Can lichen communities be used to assess short- and long-term factors affecting seral quaking aspen ( Populus tremuloides) communities at the landscape scale? Location: Bear River Range, within the Rocky Mountains, in northern Utah and southern Idaho, USA. Method: Forty-seven randomly selected mid-elevation aspen stands were sampled for lichens and stand conditions. Plots were characterized according to tree species cover, basal area, stand age, bole scarring, tree damage, and presence of lichen species. We also recorded ammonia emissions with passive sensors at 25 urban and agricultural sites throughout an adjacent populated valley upwind of the forest stands. Nonmetric multidimensional scaling (NMS) ordination was used to evaluate an array of 20 variables suspected to influence lichen communities. Results: In NMS, forest succession explained most variance in lichen composition and abundance, although atmospheric nitrogen from local agricultural and urban sources also significantly influenced the lichen communities. Abundance of nitrophilous lichen species decreased with distance from peak ammonia sources and the urban center in all aspen succession classes. One lichen, Phaeophyscia nigricans, was found to be an effective bioindicator of nitrogen loading. Conclusions: Lichen communities in this landscape assessment of aspen forests showed clear responses to long-term (stand succession) and short-term (nitrogen deposition) influences. At the same time, several environmental factors (e.g. tree damage and scarring, distance to valley, topography, and stand age) had little influence on these same lichen communities. We recommend further use of epiphytic lichens as bioindicators of dynamic forest conditions. [ABSTRACT FROM AUTHOR]

Summary. Previous studies have suggested an increased incidence of acquired severe aplastic anaemia in Asian populations. We evaluated the incidence of aplastic anaemia in people of Asian descent, using a well-defined paediatric (0–14 years) population in British Columbia, Canada to minimize environmental factors. The incidence in children of East/South-east Asian descent (6·9/million/year) and South Asian (East Indian) descent (7·3/million/year) was higher than for those of White/mixed ethnic descent (1·7/million/year). There appeared to be no contribution by environmental factors. This study shows that Asian children have an increased incidence of severe aplastic anaemia possibly as a result of a genetic predisposition. [ABSTRACT FROM AUTHOR]