Climate change and mining in Canada

Climate is an important component of the operating environment for the Canadian mining sector. However, in recent years mines across Canada have been affected by significant climatic hazards, several which are regarded to be symptomatic of climate change. For the mining sector, climate change is a pressing environmental threat and a significant business risk. The extent to which the mining sector is able to mitigate its own impact and adapt to climate change will affect its long-term success and prosperity, and have profound economic consequences for host communities. This paper draws upon case studies conducted with mining operations in Canada involving in-depth interviews with mining professionals and analysis of secondary sources to characterize the vulnerability of the Canadian mining industry to climate change. Five key findings are discussed: i) mines in the case studies are affected by climate events that are indicative of climate change, with examples of negative impacts over the past decade; ii) most mine infrastructure has been designed assuming that the climate is not changing; iii) most industry stakeholders interviewed view climate change as a minor concern; iv) limited adaption planning for future climate change is underway; v) significant vulnerabilities exist in the post-operational phase of mines. This paper argues for greater collaboration among mining companies, regulators, scientists and other industry stakeholders to develop practical adaptation strategies that can be integrated into existing and new mine operations, including in the post-operational phase.     

Does the nutrition profile of vitamins, fatty acids and microelements counteract the negative impact from organohalogen pollutants on bone mineral density in Greenland sledge dogs (Canis familiaris)?

There is a great need for understanding the impact from dietary OHCs (organohalogen compounds) on bone mineral composition - and thereby osteoporosis - in especially arctic wildlife such as polar bears (Ursus maritimus) as well as humans. For that purpose, we measured BMD (bone mineral density) by DXA scanning (g/cm(-2)) in 15 age and weight normalized sledge dog (Canis familiaris) bitches and their 26 pups divided into a control group (n=26) given 50-200 g/day clean pork (Suis scrofa) fat and a treated group (n=15) given 50-200 g/day OHC polluted minke whale (Balaenoptera acutorostrata) blubber as main lipid sources. The results showed that BMD increased significantly with age (linear regression: p<0.0001, r(2)=0.83, n=41) while no sex difference was found in the F-generation (two-way ANOVA: all p>0.3). No differences in BMD(femur) or BMD(vertebrae) between exposed and control individuals in the bitch generation were found (linear mixed effect model: both p>0.38). Likewise, no difference between exposed and control subadults and juveniles in the F-generation was found (two-way ANOVA: all p>0.33). Correlation analyses between BMD(femur), BMD(vertebrae) and groups of OHCs, respectively, did not show any statistically significant relationships nor a clear or decreasing trend (Pearson's: p: 0.07-0.78; r: -0.2-0.59; n: 10-18). As the groups were similar regarding genetics, age and sex are the only factors that can explain this observation. Either the pollutants did not have an impact on BMD using the present time frame and OHC concentrations (threshold levels not reached), or the difference in food composition (mainly vitamins and n3 fatty acids) conceal the potential OHC impact on BMD. Such information is important when evaluating the positive and negative health consequences from eating polluted marine species.     

Voluntary exercise at the expense of reproductive success in Djungarian hamsters (Phodopus sungorus)

Energy demands of gestation and lactation represent a severe challenge for small mammals. Therefore, additional energetic burdens may compromise successful breeding. In small rodents, food restriction, cold exposure (also in combination) and wheel running to obtain food have been shown to diminish reproductive outcome. Although exhibited responses such as lower incidence of pregnancy, extended lactation periods and maternal infanticide were species dependent, their common function is to adjust energetic costs to the metabolic state reflecting the trade-off between maternal investment and self-maintenance. In the present study, we sought to examine whether voluntary exercise affects reproduction in Djungarian hamsters (Phodopus sungorus), which are known for their high motivation to run in a wheel. Voluntary exercise resulted in two different effects on reproduction; in addition to increased infanticide and cannibalism, which was evident across all experiments, the results of one experiment provided evidence that free access to a running wheel may prevent successful pregnancy. It seems likely that the impact of voluntary wheel running on reproduction was associated with a reduction of internal energy resources evoked by extensive exercise. Since the hamsters were neither food-restricted nor forced to run in the present study, an energetic deficit as reason for infanticide in exercising dams would emphasise the particularly high motivation to run in a wheel.     

Methodology to translate policy assessment problems into scenarios: the example of the SEAMLESS integrated framework

Scenario-based approaches in environmental and policy assessment studies are increasingly applied within integrated assessment and modelling frameworks. The SEAMLESS project develops such an integrated framework (SEAMLESS-IF) aiming to assess, ex-ante, impacts of alternative agro-environmental policies on the sustainability of agricultural systems. A particular challenge in this context is the consistent translation of a wide range of policy questions into scenarios that a modelling framework can assess. The present work defines a methodology for scenario-development in integrated policy assessment with specific emphasis on SEAMLESS-IF. After a general overview on scenario concepts for integrated policy assessment the adopted scenario concept and its development procedure is presented. They allow building integrated scenarios capturing the range of drivers of the assessed agricultural system in a consistent way across temporal and spatial scales. Then focus is on the particular procedures to translate the policy assessment questions into scenario parameters and to implement these parameters into SEAMLESS-IF. Two examples targeted at European and regional level combining integrated assessments of policy changes and technological innovations are considered to illustrate the SEAMLESS scenario concept. We conclude that the proposed methodology to translate policy assessment problems into scenarios effectively supports integrated assessment in SEAMLESS-IF or even in other modelling frameworks.     

Economic impacts of climatic variability and subsidies on European agriculture and observed adaptation strategies

In order to assess agricultural adaptation to climate impacts, new methodologies are needed. The translog distance function allows assessing interactions between different factors, and hence the influence of management on climate impacts. The Farm Accountancy Data Network provides extensive data on farm characteristics of farms throughout the EU15 (i.e. the 15 member states of the European Union before the extension in 2004). These data on farm inputs and outputs from 1990−2003 are coupled with climate data. As climate change is not the only change affecting European agriculture, we also include effects of subsidies and other changes on inputs and outputs of farms throughout Europe. We distinguish several regions and empirically assess (1) climate impacts on farm inputs and outputs in different regions and (2) interactions between inputs and other factors that contribute to the adaptation to these impacts. Changes in production can partly be related to climatic variability and change, but also subsidies and other developments (e.g. technology, markets) are important. Results show that impacts differ per region, and that ‘actual impacts’ cannot be explicitly separated into ‘potential impacts’ and ‘adaptive capacity’ as often proposed for vulnerability assessment. Farmers adapt their practices to prevailing conditions and continuously adapt to changing conditions. Therefore, ‘potential impacts’ will not be observed in practice, leaving it as a mainly theoretical concept. Factors that contribute to the adaptation also differ per region. In some regions more fertilizers or more irrigation can mitigate impacts, while in other regions this amplifies impacts. To project impacts of future climate change on agriculture, current farm management strategies and their influence on current production should be considered. This clearly asks for improved integration of biophysical and economic models.     

Patterns of shell repair in articulate brachiopods indicate size constitutes a refuge from predation

The cost of overcoming prey defenses relative to the value of internal tissues is a key criterion in predator/prey interactions. Optimal foraging theory predicts: (1) specific sizes of prey will result in the best returns to predators, and (2) there will often be a size at which the cost/benefit balance is low enough to effectively exclude predation. Data presented here on styles of repaired shell damage and size at which injury had been sustained was collected from samples of terebratulide brachiopods from the Antarctic Peninisula (Liothyrella uva), Falkland Islands (Magellania venosa and Terebratella dorsata) and Chile (M. venosa). The predominant form of damage on shells was indicative of predators attacking the valve margins. The modal size for repaired damage was more than 10 mm smaller than the modal size for the overall size distribution in each species and there were no repaired attacks in the largest size classes of any species. These data suggest that size forms a refuge from predation, as would be predicted by optimal foraging theory. The optimal sizes that predators appeared to attack vary between species, as do the sizes that provided a refuge from predation. High levels of multiple repairs (19% of the M. venosa population from the Falkland Islands sampled had 2 or more repairs) suggest that the mortality following attack is low, suggesting that many predators abandon their attacks.     

Abiotic conditions in cephalopod (Sepia officinalis) eggs: embryonic development at low pH and high pCO2

Low pO₂ values have been measured in the perivitelline fluids (PVF) of marine animal eggs on several occasions, especially towards the end of development, when embryonic oxygen consumption is at its peak and the egg case acts as a massive barrier to diffusion. Several authors have therefore suggested that oxygen availability is the key factor leading to hatching. However, there have been no measurements of PVF pCO₂ so far. This is surprising, as elevated pCO₂ could also constitute a major abiotic stressor for the developing embryo. As a first attempt to fill this gap in knowledge, we measured pO₂, pCO₂ and pH in the PVF of late cephalopod (Sepia officinalis) eggs. We found linear relationships between embryo wet mass and pO₂, pCO₂ and pH. pO₂ declined from >12 kPa to less than 5 kPa, while pCO₂ increased from 0.13 to 0.41 kPa. In the absence of active accumulation of bicarbonate in the PVF, pH decreased from 7.7 to 7.2. Our study supports the idea that oxygen becomes limiting in cephalopod eggs towards the end of development; however, pCO₂ and pH shift to levels that have caused significant physiological disturbances in other marine ectothermic animals. Future research needs to address the physiological adaptations that enable the embryo to cope with the adverse abiotic conditions in their egg environment. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Effect of elevated CO2 on coarse-root biomass in Florida scrub detected by ground-penetrating radar

Growth and distribution of coarse roots in time and space represent a gap in our understanding of belowground ecology. Large roots may play a critical role in carbon sequestration belowground. Using ground-penetrating radar (GPR), we quantified coarse-root biomass from an open-top chamber experiment in a scrub-oak ecosystem at Kennedy Space Center, Florida, USA. GPR propagates electromagnetic waves directly into the soil and reflects a portion of the energy when a buried object is contacted. In our study, we utilized a 1500 MHz antenna to establish correlations between GPR signals and root biomass. A significant relationship was found between GPR signal reflectance and biomass (R2 = 0.68). This correlation was applied to multiple GPR scans taken from each open-top chamber (elevated and ambient CO2). Our results showed that plots receiving elevated CO2 had significantly (P = 0.049) greater coarse-root biomass compared to ambient plots, suggesting that coarse roots may play a large role in carbon sequestration in scrub-oak ecosystems. This nondestructive method holds much promise for rapid and repeatable quantification of coarse roots, which are currently the most elusive aspect of long-term belowground studies.     

Poleward shifts in winter ranges of North American birds

Climate change is thought to promote the poleward movement of geographic ranges; however, the spatial dynamics, mechanisms, and regional anthropogenic drivers associated with these trends have not been fully explored. We estimated changes in latitude of northern range boundaries, center of occurrence, and center of abundance for 254 species of winter avifauna in North America from 1975 to 2004. After accounting for the effect of range size and the location of the northern boundary, positive latitudinal trends were evident for the northern boundary (1.48 km/yr), center of occurrence (0.45 km/yr), and center of abundance (1.03 km/yr). The northern boundary, when examined across individual species, had the most variable trends (SD = 7.46 km/yr) relative to the center of occurrence (SD = 2.36 km/yr) and center of abundance (SD = 5.57 km/yr). Trends did not differ based on migratory status, but there was evidence that trends differed for species with ranges centered in the southern vs. northern portion of the study area. Species occurred more sporadically over time at northern range boundaries, and northern boundaries were associated with a concentration of colonization and extirpation events, with a greater prevalence of colonization events likely promoting poleward trends. Regional anthropogenic drivers explained approximately 8% of the trend for the northern boundary, 14% for the center of occurrence, and 18% for the center of abundance; however, these effects were localized in the northern portion of species' ranges and were associated with distributional changes within ranges, primarily abundance, producing patterns that mimicked poleward movements. We conclude that poleward distributional shifts represent the interaction between climate change and regional factors whose outcome is determined by the scale of the analysis and the biotic and abiotic features in the region, and how anthropogenic activities have impacted these features.     

Moss harvest truncates the successional development of epiphytic bryophytes in the Pacific Northwest.

We evaluated the impact of commercial moss harvest on the development of an understory epiphyte community in the Pacific Northwest by characterizing natural development stages using data from both a long-term regrowth study and demographic sampling. First, experimentally stripped 1 m long cylindrats on 46 shrub stems in the Oregon Coast Range were monitored for species composition and abundance annually during the first five years of recovery and again in year 10. Second, a pathway of community development was inferred by examining the relative species composition and abundance of epiphytic species present in moss mats in a four-stage chronosequence. We (1) characterized the change in richness and composition from year 1 through 10 of regrowth following experimental disturbance, (2) quantified the proportion of approximately 1-, 10-, 25-, and 50-year-old moss mats of commercially harvestable species that were monodominant, diverse, and late successional, and (3) contrasted these proportions with estimates from a compositional transition matrix derived from long-term monitoring. Roughly half of the observed moss mats demonstrated neutral dynamics and were composed of a mixture of readily dispersed acrocarps and pleurocarps. The remaining half exhibited positive dynamics and were dominated by aggressively growing pleurocarpous species such as Isothecium myosuroides. Following structural developmental pathways well established for vascular plants, moss mats shift with time from high diversity and evenness in the initial colonization and extended establishment phases to increasing Isothecium dominance during a presumed competitive-exclusion phase. Old mats exist in alternate states of either Isothecium dominance or mixed composition, either of which may have late-successional species. Patchy historic commercial moss harvest likely facilitated high diversity by increasing the simultaneous occurrence of all moss mat age classes, while modern strip harvesting methods are predicted to promote predominantly even-aged mats that are unlikely to reach "old-growth" conditions before re-harvest.