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1.
Environ Entomol ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748595

RESUMO

During the eradication program undertaken against Anoplophora glabripennis (Motschulsky) in the Greater Toronto Area, information was collected on the numerous signs of injury found on wounded trees. Herein, we used a portion of this information to assess the characteristics of logs with signs of oviposition (i.e., pits). Specifically, we related the basal diameter, type (log bole vs. log branch), height above ground, and branch hierarchy level of logs with pits to tree size (i.e., height and diameter at breast height) and level of infestation intensity. In general, pits were concentrated on logs from the bole and branches that were 8-14 cm in diameter in the lower 8 m of the bole and in the first 2 levels of the branching hierarchy. Oviposition pit location was strongly influenced by tree size-both height and diameter at breast height, with more pits on the lower bole in small trees and then higher on the bole and into the branches as tree size increased. As tree-level infestation intensity increased, pits were found on both larger and smaller diameter portions of the trees, presumably as preferred oviposition sites became saturated. These findings can improve the efficacy of surveillance activities for A. glabripennis.

2.
Sci Rep ; 10(1): 19391, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33173065

RESUMO

We assess risks posed by oak wilt-a disease caused by the fungal pathogen Bretziella fagacearum. Though not currently found in Canada, our distribution models indicate that suitable climate conditions currently occur in southern Ontario for B. fagacearum and two of its main insect dispersal vectors, Colopterus truncatus and Carpophilus sayi. Climate habitat for these species is projected to expand northward under climate change, with much of the oak range in eastern Canada becoming climatically suitable within the next two decades. Potential costs for the removal and replacement of oak street trees ranged from CDN$266 to $420 million, with variation related to uncertainty in costs, rate of tree replacement, and city-level estimates of oak street tree density. The value of standing oak timber in eastern Canada was estimated at CDN$126 million using provincial stumpage fees and as a CDN$24 million annual contribution to national Gross Domestic Product (GDP) when calculated using a combination of economic and forestry product statistics. These values can help inform the scale of eradication and/or management efforts in the event of future oak wilt introductions.


Assuntos
Quercus/parasitologia , Animais , Ascomicetos/patogenicidade , Mudança Climática , Conservação dos Recursos Naturais/economia , Ecossistema , Monitoramento Ambiental/métodos , Ontário
3.
J Econ Entomol ; 113(2): 839-850, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-31808523

RESUMO

The Asian longhorned beetle (Anoplophora glabripennis Motschulsky) continues to pose a significant risk to deciduous forests around the world. We assess Asian longhorned beetle-related risks in eastern Canada by generating current and future climate suitability maps, import-based likelihood of introduction estimates for each urban center in our study area, and potential economic impacts in both urban and natural settings. For the current period, climatic suitability for Asian longhorned beetle was highest in southern Ontario, but was projected to expand significantly northward and eastward by midcentury. High likelihood of Asian longhorned beetle introduction was associated with large urban centers, but also smaller centers with high levels of pest-associated imports. Potential costs for the removal and replacement of Asian longhorned beetle-impacted street trees ranged from CDN$8.6 to $12.2 billion, with the exact amount and city-level ranking depending on the method used to calculate risk. Potential losses of merchantable maple (Acer) timber were estimated at CDN$1.6 billion using provincial stumpage fees and CDN$431 million annually when calculated using a combination of economic and forestry product statistics. The gross value of edible maple products, which could potentially be affected by Asian longhorned beetle, was estimated at CDN$358 million annually. These values can help inform the scale of early detection surveys, potential eradication efforts, and research budgets in the event of future Asian longhorned beetle introductions.


Assuntos
Acer , Besouros , Animais , Cidades , Ontário , Árvores
4.
Sci Rep ; 7: 43881, 2017 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-28266577

RESUMO

The growth response of trees to ongoing climate change has important implications for future forest dynamics, accurate carbon accounting, and sustainable forest management. We used data from black spruce (Picea mariana) and jack pine (Pinus banksiana) provenance trials, along with published data for three other northern conifers, to identify a consistent growth response to climate warming in which cold-origin populations are expected to benefit and warm-origin populations are expected to decline. Specifically, populations from across the geographic range of a species appear to grow well at temperatures characteristic of the southern portion of the range, indicating significant potential for a positive growth response to climate warming in cold-origin populations. Few studies have quantified and compared this pattern across multiple species using provenance data. We present a forest regeneration strategy that incorporates these anticipated growth responses to promote populations that are both local to the planting site and expected to grow well under climate change.


Assuntos
Mudança Climática , Florestas , Picea/crescimento & desenvolvimento , Pinus/crescimento & desenvolvimento , Temperatura , Canadá , Carbono/metabolismo , Conservação dos Recursos Naturais/métodos , Geografia , Picea/metabolismo , Pinus/metabolismo , Árvores/crescimento & desenvolvimento , Árvores/metabolismo , Estados Unidos
5.
PLoS One ; 11(8): e0157425, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27513660

RESUMO

Climate-influenced changes in fire regimes in northern temperate and boreal regions will have both ecological and economic ramifications. We examine possible future wildfire area burned and suppression costs using a recently compiled historical (i.e., 1980-2009) fire management cost database for Canada and several Intergovernmental Panel on Climate Change (IPCC) climate projections. Area burned was modelled as a function of a climate moisture index (CMI), and fire suppression costs then estimated as a function of area burned. Future estimates of area burned were generated from projections of the CMI under two emissions pathways for four General Circulation Models (GCMs); these estimates were constrained to ecologically reasonable values by incorporating a minimum fire return interval of 20 years. Total average annual national fire management costs are projected to increase to just under $1 billion (a 60% real increase from the 1980-2009 period) under the low greenhouse gas emissions pathway and $1.4 billion (119% real increase from the base period) under the high emissions pathway by the end of the century. For many provinces, annual costs that are currently considered extreme (i.e., occur once every ten years) are projected to become commonplace (i.e., occur once every two years or more often) as the century progresses. It is highly likely that evaluations of current wildland fire management paradigms will be necessary to avoid drastic and untenable cost increases as the century progresses.


Assuntos
Mudança Climática/estatística & dados numéricos , Bombeiros , Incêndios/economia , Modelos Teóricos , Árvores , Canadá , Ecossistema , Humanos , Fatores de Tempo
6.
Environ Monit Assess ; 184(8): 4655-69, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21887479

RESUMO

Canada's National Forest Inventory (CanFI) provides coarse-grained, aggregated information on a large number of forest attributes. Though reasonably well suited for summary reporting on national forest resources, the coarse spatial nature of this data limits its usefulness in modeling applications that require information on forest composition at finer spatial resolutions. An alternative source of information is the land cover classification produced by the Canadian Forest Service as part of its Earth Observation for Sustainable Development of Forests (EOSD) initiative. This product, which is derived from Landsat satellite imagery, provides relatively high resolution coverage, but only very general information on forest composition (such as conifer, mixedwood, and deciduous). Here we link the CanFI and EOSD products using a spatial randomization technique to distribute the forest composition information in CanFI to the forest cover classes in EOSD. The resultant geospatial coverages provide randomized predictions of forest composition, which incorporate the fine-scale spatial detail of the EOSD product and agree in general terms with the species composition summaries from the original CanFI estimates. We describe the approach and provide illustrative results for selected major commercial tree species in Canada.


Assuntos
Conservação dos Recursos Naturais , Monitoramento Ambiental/métodos , Árvores/crescimento & desenvolvimento , Biodiversidade , Canadá , Ecossistema , Agricultura Florestal/estatística & dados numéricos , Árvores/classificação
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