Methods and Applications for Assessing Ecosystem Impacts of Natural Climate Fluctuations and Human Activities with Emphasis on Western Canada

我最近的研究产生了(I)与紧迫的保护问题相关的生态系统相互作用的基本见解，以及(Ii)用于生态系统研究的宝贵统计工具。这项研究的大部分内容都集中在不列颠哥伦比亚省中央海岸严重萧条的奥维涅诺湖红鲑鱼种群。我打算寻求一个关于这些红鲑鱼向海迁徙过程中生态系统相互作用的特别重要的发现，以确定这些相互作用在多大程度上可能是其他种群所共有的。我还打算对这个项目产生的广泛有用的统计方法作出重大改进。最后，我建议继续追寻18.6年的月节周期对加拿大西部水生和陆地生态系统的影响的几个意想不到的但强烈的暗示。下面我对最后两个挑战做一个总结。 研究问题：可以为函数回归分析开发更严格的同时置信限吗？在许多情况下，人们试图深入了解每天监测的物理参数(如河流流量)和生物变量(如迁出的红鲑鱼群体的海洋存活率)之间的关系。例如，河流排放是否与海洋生存有关？如果是这样，一年中的哪一段时间？函数回归分析将x变量实际上是随时间变化的函数(每日河流流量)与y变量(海洋年存活率)联系起来，并提供了解决这些问题的方法。在这种分析中，随着时间的推移，标准线性回归方程中的回归系数被函数所取代。然后，上面的第二个问题变成了“回归函数在哪些天是非零的？”这是一个同时推理问题，类似于与方差分析相关的均值的标准多重比较。我和另外两个人最近提出的方法，提供了适当的保护，防止出现重大错误，但相对保守(类似于舍夫的S方法，用于多重比较均值)。我建议使用所谓的基于管子的分析方法来降低这种保守性。我们的建议已经获得了支持，这样的改进将增强其实用性。 研究问题：18.6年的月节周期(在月球和太阳的视在路径上的相对方向)在多大程度上影响北美西部的陆地和水生生态系统？最近描述了这一周期的潜在海洋和气候影响，包括北美太平洋沿岸的海面和大气影响，并对可能的原因机制进行了模拟。我与其他人合作，在加拿大西部的几个水生和陆地生态系统中发现了强烈的周期性波动迹象，包括(I)养殖湖泊中幼鱼红鲑鱼丰度的指标，(Ii)沿海洪泛平原的氮浓度，(Iii)内陆湖泊的木炭浓度，以及(Iv)湖流域的树木生长速度。在对加拿大西北部亚高山冷杉和黑云杉生长的档案记录进行的特别分析中，我也发现了类似的周期性。我打算通过(I)为鲑鱼丰度指标产生更进一步、更精细的分辨率和更长的时间序列，(Ii)对存档的树木生长记录进行更严格和更广泛的评估，以及(Iii)从上述树木生长依赖似乎最强烈的地区--不列颠哥伦比亚省西北角和邻近的育空地区--收集进一步的证据，以追求这一非凡的、偶然的发现。

My recent research has generated (i) fundamental insight on ecosystem interactions associated with pressing conservation concerns, and (ii) a valuable statistical tool for use in ecosystem research. Much of this research was focused on the severely depressed, Oweekeno Lake sockeye salmon population on the British Columbia Central Coast. I intend to pursue a particularly significant finding regarding the ecosystem interactions in the seaward migration of these sockeye salmon to ascertain the extent to which these might be common to other populations. I also intend to make significant improvements to widely useful statistical methodology that emerged from this project. Finally, I propose to pursue several, unanticipated but strong hints of an impact of the 18.6-year lunar nodal cycle on both aquatic and terrestrial ecosystems in western Canada. I provide a summary of the last two of these challenges below. Research Question: Can tightened simultaneous confidence bounds be developed for functional regression analyses? There are many instances where insight is sought on the relationship between a physical parameter (such as river discharge) that is monitored daily and a biological variable (such as marine survival for an out-migrating cohort of sockeye salmon). Is, e.g., river discharge linked to marine survival? And if so, over what portion of the year? Functional regression analysis links an x-variable that is in fact a function over time (daily river discharge), to a y-variable (annual marine survival), and provides a means for addressing these questions. In this analysis, the regression coefficient in a standard linear regression equation is replaced by a function over time. The second question above then becomes, "For which days is the regression function non-zero? ". This is a simultaneous inference problem, akin to standard multiple comparisons of means associated with an analysis of variance. The approach that I and two others proposed recently provides appropriate protection against false claims of significance, but is relatively conservative (akin to Scheffé's method for multiple comparisons of means). I propose to use so-called tube-based, analytical methods to reduce this conservatism. Our proposal is already gaining traction, and such an improvement would enhance its utility. Research Question: To what extent does the 18.6-year lunar nodal cycle (in the relative orientations of the apparent paths of the moon vs. the sun) influence terrestrial and aquatic ecosystems in Western North America? Potential oceanographic and climate-related impacts of this cycle have recently been described, including sea surface and atmospheric impacts along the Pacific Coast of North America, and potential causal mechanisms have been modeled. I, in collaboration with others, have found strong hints of periodic fluctuations in several aquatic and terrestrial ecosystems in western Canada, including (i) a proxy for juvenile sockeye salmon abundance in a rearing lake, (ii) nitrogen concentrations in a coastal flood plain, (iii) charcoal concentrations in an inland lake, and (iv) tree growth rates in the lake watershed. I have also found similar periodicities in an ad hoc analysis of archived records for the growth of subalpine fir and black spruce in north-western Canada. I intend to pursue this remarkable, serendipitous discovery by (i) generating further, finer-resolution and longer time series for the proxy for salmon abundance, (ii) performing a more rigorous and extensive assessment of the archived tree growth records, and (iii) collecting further evidence from the area where the above tree-growth dependence appears to be strongest – in the northwest corner of British Columbia and adjacent Yukon Territory.