"Carbon and water balances of hybrid poplar plantations, and lodgepole pine and Douglas-fir stands"

我的研究目的是更好地了解杂交杨(HP)人工林、从山松甲虫(MPB)攻击中恢复的小松林和管理的沿海豆杉(DF)林的碳(C)、水和能量平衡。将使用微气象方法涡动协方差(EC)对生态系统净生产力(即碳固存或损失)和蒸散量(即用水量)进行全年测量。我的惠普研究的目的之一是确定草原地区不同树龄的惠普种植园将C作为植物生物量(用于纤维或生物能源生产)和土壤有机质的封存能力。由于HP种植园对水的要求很高，一个关键目标将是通过比较用水量和降雨量来确定大片种植园的可持续性。将确定对地下水排泄率的影响，并评估对区域水平衡的影响。在我的MPB研究中，一个重要的目标是测量当死亡的树木开始倒下并有可能增加腐解率时，未砍伐林分的C平衡的恢复速度。此外，使用部分打捞收获(只移走松树)而不是砍伐打捞收获(这会造成大量的碳损失)的可行性将通过评估前者的风害和碳封存来确定。基于过程的森林生产模型(3PG)将与几种管理方案一起使用，以估计我们MPB研究地点附近的碳平衡可能在不久的将来发生的变化。我的DF研究将专注于测量一个23年生的林分在2007年施肥时的强烈生长反应，因为它开始排挤竞争对手的林下植被。此外，采伐(2011年1月)新培肥的61年生林分的采伐造成的碳损失将使用EC来衡量，直到2013年。控制过程将通过测量土壤和木本植物收获碎片的呼吸作用、土壤表面甲烷和一氧化二氮通量、溪水中碳的运移速率和收获后土壤水分状况的变化来研究。

The goal of my research is to better understand the carbon (C), water and energy balances of hybrid poplar (HP) plantations, lodgepole pine stands recovering from mountain pine beetle (MPB) attack, and managed coastal Douglas-fir (DF) stands. A micrometeorological method, eddy covariance (EC), will be used to make year-round measurements of net ecosystem productivity (i.e., C sequestration or loss) and evapotranspiration (i.e., water use). One aim of my HP research is to determine the capacity of different-aged HP plantations in the Prairie region to sequester C as plant biomass (for fibre or bioenergy production) and soil organic matter. Because of the high water requirements of HP plantations, a key objective will be to determine the sustainability of extensive plantations by comparing water use and precipitation. Effects on the rate of water drainage to the water table will be determined and the implications for the regional water balance assessed. In my MPB research, an important objective is to measure the rate of recovery of the C balance in non-harvested stands when killed trees are starting to fall with the possibility of increasing decomposition rates. In addition, the feasibility of using partial salvage harvesting (removing only pine trees) rather than clearcut salvage harvesting (which results in large C losses) will be determined by assessing wind damage and C sequestration in the former. A process-based forest production model (3PG) will be used with several management scenarios to estimate likely near-future changes in the C balance in the vicinity of our MPB research sites. My DF research will focus on measuring the strong growth response of a 23-year-old stand fertilized in 2007 as it begins to crowd out competing understory vegetation. In addition, the losses of C from a clearcut resulting from the harvesting (in Jan 2011) of a recently-fertilized 61-year-old stand will be measured using EC until 2013. Controlling processes will be studied using measurements of respiration by soil and woody harvesting debris, soil-surface methane and nitrous oxide fluxes, rates of C transport in stream water, and post-harvesting changes in the soil water regime.