Relations between forest disturbance, in-stream wood and aquatic habitat over river networks

森林溪流中的入流木材或大型木质残体（LWD）是鱼类种群栖息地和覆盖物的重要贡献之一。随钻测井在河段尺度上得到了广泛的研究。然而，很少有人知道LWD的变异性及其在多个空间尺度上的生态功能。 Swanson（2003）建议，从景观角度研究随时间推移的LWD生态学是未来最需要的研究方向之一。人们普遍认为，必须在时间和空间尺度上界定森林的可持续性。 研究自然干扰有助于理解时间尺度上的生态过程和格局。这对加拿大森林来说尤其重要，因为野火频繁。 由NSERC发现补助金资助，我的第一个五年（2002-2006）的研究项目主要集中在LWD长期动态（时间尺度）在收获和野火干扰的森林流域在BC内陆。这项新提议的研究（2007-2011年）将以多个空间尺度的河流网络上的LWD生态为目标。我的具体目标包括：（1）不同河流等级下LWD负载量与其生态功能之间关系的量化;（2）野火与采伐干扰之间上述关系的比较;（3）确定控制LWD数量和在河网上分布的关键机制。 我的长期研究目标是：（1）在空间和时间尺度上整合LWD负载和功能的信息，以充分了解LWD生态;（2）将我们的结果与加拿大亚寒带流域的可持续森林和流域管理联系起来。

SummaryIn-stream wood or large woody debris (LWD) in forested streams is one of most important contributions of habitat and cover for fish populations. LWD has been intensively studied at the reach scale. However, little is known about variability of LWD and its ecological functions at multiple spatial scales.  Swanson (2003) suggested that a landscape perspective on LWD ecology over river networks and through time is one of the most needed future research directions. It is widely accepted that forest sustainability must be defined in temporal and spatial scales.  Studying natural disturbance is useful for understanding ecological processes and patterns at temporal scales. This is particularly important for the Canadian forests because of frequent wildfire.   Funded by a NSERC discovery grant, my first five-year (2002-2006) research project mainly focused on LWD long-term dynamics (temporal scales) in harvested and wildfire-disturbed forest watersheds in the BC interior. This new proposed research (2007-2011) will target LWD ecology over river networks at multiple spatial scales. My specific objectives include: (1) quantification of relations between LWD loadings and their ecological functions at various stream orders; (2) comparison of the above relations between wildfire and harvesting disturbances; and (3) determination of key mechanisms controlling LWD amount and distribution over river networks.  My long-term research goals are: (1) to integrate information of LWD loadings and functions at both spatial and temporal scales to fully understand LWD ecology; and (2) to link our results with sustainable forest and watershed management in the Canadian sub-boreal watersheds.