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In this paper we provide an overview of an integrated approach to modelling the risks and impacts associated with non-indigenous forest pest species. This is a broad and important topic given the scale of ecological and economic consequences associated with non-indigenous species in North America and elsewhere. Assessments of risks and impacts remain difficult due to complexities and interactions between the many factors driving invasions and outcomes. These processes occur across various spatial and temporal scales, and are often influenced and complicated by human activities. For each component of an ecological invasion (i.e., arrival, establishment, and spread), we review general approaches for modelling the phenomenon and identify data and knowledge gaps. With the greater availability of various spatial data and computational power we suggest the possibility of linking the models for each invasion component into a more integrated framework, thus allowing interactions and feedbacks between components to be better incorporated into risk modelling efforts. The approach is illustrated using examples from current work with Sirex noctilio Fabricius--a relatively new invasive wood wasp in eastern North America. Key words: invasive species, integrated modelling, risk assessment, impact assessment, Sirex noctilio. Les auteurs presentent le survol d'une approche integree pour la modelisation des risques et des impacts associes aux pestes foreslieres non indigenes. II s'agit d'un sujet large et important, compte lenu de l'echelle el des consequences economiques associees aux especes non indigenes, en Amerique du Nord et ailleurs. Les evaluations de risques el d'impacis demeureni diffieiles a cause de la complexity el des inieraclions avec plusieurs facteurs responsables des invasions el de leurs consequences. Ces processus s'effectuent selon differences echelles spatio-temporelles, et sont souvent influences et compliques par les activites humaines. Pour chaque composante d'une invasion ecologique (c.-a-d. arrivee, etablissement et diffusion), les auteurs passent en revue les approches generates pour la modelisation du phenomene ainsi que I'identification des donnees et les manques de connaissance. Avec la disponibilite accrue de diverses donnees spatiales et des capacites informatiques, les auteurs suggerent la possibilite de lier les modeles de chaque composante dans un cadre plus integre, permettant ainsi de mieux incorporer les interactions et les retroactions entre les composantes dans les efforts de modelisation des risques. On illustre cette approche en utilisant des exemples provenant du travail actuel sur le Sirex noctilio Fabricius, une guepe perce-bois envahissante relativement nouvelle dans l'est de l'Amerique du Nord. Mots-cles : especes envahissantes, modelisation integree, evaluation des risques, evaluation des impacts, Sirex noctilio. [Traduit par la Redaction], Introduction The management of non-indigenous species is complex, but critical given potentially large economic and ecological impacts. Gross annual economic losses and control costs in agricultural and forestry sectors due [...]

Climate change is the most challenging issue of our time. While climate change is often portrayed as a global phenomenon, the real impacts of climate change are felt at the local level. Changes in climatic conditions directly affect the level of precipitation which is very important for crop production in Ontario. How do changes in climate affect corn and soybean yields at the county level in Ontario? This question is addressed in this paper by estimating the effects of climatic and economic factors on yields of grain corn and soybean in three selected counties in Southwestern Ontario employing data from 1950 to 2013. The results demonstrate that the effect of precipitation during growing season on yield is positive and statistically significant and it is consistent across the selected counties. The effects of solar energy on crop yields vary across counties. Yields of both crops increase as crop price increases and decline as the price of fertilizer increases. Finally, developments in technology have a strong effect on enhancing yield for both crops. The climatic factors have a larger impact than the effects of economic factors on corn yields at the county level. The reverse, however, appears to be true for soybean production at the county level in Ontario. The policy implications of the results are also discussed. [ABSTRACT FROM AUTHOR]

We explore the biophysical potential and economic attractiveness of black spruce (Picea mariana) regeneration in eastern Canada under the high greenhouse gas emission scenario (RCP 8.5) of the Intergovernmental Panel on Climate Change (IPCC). The study integrates net primary productivity and net ecosystem productivity estimates from three major global climate models (GCMs), growth and yield equations specific to black spruce, and economic analyses to determine spatially varying investment values of black spruce regeneration-both including and excluding carbon sequestration benefits. Net present value (NPV) was used to represent financial attractiveness. It was assumed that stands would not be harvested at volumes less than 80 m3·ha-1. A baseline case with the stumpage price set to $20 m-3, stand establishment cost $500 ha-1, and the discount rate 4%, was used with wide-ranging sensitivity analyses conducted around these assumptions. These values represent the wide range of choices and outcomes possible with black spruce regeneration investments. The results indicated a latitudinal gradient in economic attractiveness, with higher forest productivity and NPVs in the southern portion of the study area; however, black spruce regeneration was not economically attractive unless regeneration costs were very low (representing something closer to a natural regeneration type scenario) and/or carbon sequestration benefits of at least $5 ton-1 CO2 were realized. In general, the optimal harvest rotation age increased with increasing carbon price by approximately 9 to 18 years. Results of this study highlight the importance of future price and yield expectations and establishment costs in evaluating forest investments. [ABSTRACT FROM AUTHOR]