Hybrid poplar productivity under high forest and short rotation woody crop systems under boreal conditions

杂交杨树是加拿大所有树种中生长潜力最快的树种。然而，在加拿大的北方地区，它们的使用相对较晚，在不同的场地条件和造林管理方案下，它们的耐寒性和生长性能仍然存在一些不确定性。利用已建立的人工林，我们首先想确定环境因素和栽培方法对速生杂交杨林产量的影响。更具体地说，我们试图1)评估几种杂交杨树品种的产量潜力，这些品种种植在覆盖阿比蒂比-塔姆斯卡明格和北杜-塔姆斯卡明格地区的大土壤-气候梯度上；2)确定栽培制度（即高林造林与短轮作林地）和施肥对种植园产量的影响。最终，我们试图确定一套土壤气候条件和栽培特征（例如，分支形式，根系，生理），以及有利于在粘土带地区或魁北克西北部获得更高产量的栽培实践。该项目的结果将使在北方条件下经营的加拿大工业能够选择适当的管理做法，以便在高森林和短轮作木本作物系统下最大限度地提高生物量产量。研究结果将指导管理（工业和监管机构），并使这些快速生长的人工林在林农的工具集中得以实现，至少在靠近工厂的地方生产部分木材供应，最终减少对天然森林的依赖，减轻木材短缺和公共土地上采伐的限制。

Hybrid poplars have the fastest growth potential of all tree species found in Canada. Their use is however relatively recent in the boreal zones of Canada, and some uncertainties remain in relation to their hardiness and growth performance under differing sites conditions and silvicultural management scenarios. Using already-established plantations, we first want to determine the effects of environmental factors and cultivation practices on the yields of fast growing hybrid poplar plantations. More specifically, we seek to 1) evaluate the yield potential of several hybrid poplar cultivars planted along a large pedo-climatic gradient covering the Abitibi-Témiscamingue and Nord-du-Québec regions and 2) determine the effects of cultural system (i.e. high forest plantation vs. short rotation coppice) and fertilization on plantation yields. Ultimately, we seek to determine the set of pedo-climatic conditions and cultivar characteristics (e.g. branch form, root system, physiology), and cultivation practices that are conducive to greater yields in the clay belt region or north western Quebec. Results of this project will allow the Canadian industry operating under boreal conditions to choose appropriate management practices to maximize biomass yields under high forest and short-rotation woody crops systems. The results will guide management (industrial and regulators) and materialize the use of these fast-growing plantations in the toolset of foresters to produce at least part of their timber supply, close to mills, and ultimately be less reliant on natural forests and alleviate wood shortages and harvesting limitations on public lands.