Impact of the mountain pine beetle outbreak on the carbon and water balances of lodgepole pine stands in the BC interior

对受山松甲虫(MPB)影响的松林的管理反应各不相同，从完全移除松树冠层和次生结构(幼树、幼苗、灌木和草本植物)到选择性地移除受MPB影响的树木并保留不同程度的次生结构，到完全非侵入性的策略，即允许次生结构在死林中不受干扰地生长。适当的管理对策必须在次级结构各组成部分未来的潜在经济可行性与保护生境、生态系统生物多样性和尽量减少对林分和周围生态系统碳和水平衡的干扰之间取得平衡。不列颠哥伦比亚省内陆混交林目前倾向于采伐林木，反映了市场对某些类型木材和纸制品的需求现实。然而，许多受影响的松林中存在重要的次生结构，如果在打捞-伐木作业期间保存下来，可以为中期(15-30年)木材收获提供机会，为野生动物提供栖息地，并减少向河流和溪流的径流。通过研究残留林和非残伐林的林分生物量积累、蒸散量和小气候的变化，我们将确定受MPB影响的森林生态系统的相对健康和弹性，目的是建议对MPB暴发的最佳管理反应或反应组合。利用遥感仪器和根据实地测量的生态系统光合作用和分解进行校准的植被模型，将使研究结果能够从林分水平扩展到地貌。

Management responses to mountain pine beetle (MPB)-affected lodgepole pine stands vary from complete removal of the pine canopy and secondary structure (saplings, seedlings, shrubs and herbaceous plants) to selective removal of MPB-affected trees with varying degrees of secondary structure retention, to completely non-invasive strategies, i.e., allowing secondary structure to grow undisturbed in a dead stand. The appropriate management response must balance the potential future economic viability of components of the secondary structure with the need to preserve habitat, ecosystem biodiversity and to minimize disturbance to the carbon and water balances of the stand and surrounding ecosystems. The current bias towards clearcut harvesting in mixed-species stands in the BC Interior reflects the realities of market demand for certain types of wood and paper products. However, the presence of significant secondary structure in many of the affected pine stands could provide opportunities for mid-term (15-30 years) timber harvest, provide habitat for wildlife and reduce run-off to rivers and streams if preserved during salvage-logging operations. By studying changes to stand-level biomass accumulation, evapotranspiration, and microclimate of the residual forest ecosystems in salvage-logged and non-salvage-logged stands, we will determine the relative health and resiliency of MPB-affected forest ecosystems, with the aim of recommending the best management response or combination of responses to the MPB outbreak. The use of remote sensing instruments and vegetation models calibrated against field measurements of ecosystem photosynthesis and decomposition will allow the results of the study to be scaled from stand level to the landscape.