Linking arthropod biodiversity and food webs with changes in surface and below-ground detritus

生物多样性与生态系统功能之间的关系在生态学中继续获得相关性。 增加多样性被认为通过选择[也称为“取样”效应]和互补效应影响生态系统功能，互补效应将具有上级性能的物种的效应与协同物种混合物的效应分开。 关键的生态系统功能，如北方森林中碎屑生物量的分解，进一步受到地上和地下社区之间相互作用的调节。 我将比较表面和埋藏的CWM之间的sacrylic节肢动物和真菌的多样性1）混合木材和黑云杉为主的年代序列[跨越>300年]和2）管理杰克松林，其中CWM体积已经通过森林采伐实验改变。 然后，我将进行一系列的控制实验，物种和功能组的多样性依次增加在三个营养水平[木材腐烂真菌，食真菌动物和捕食者]和木材分解率的整体影响进行测量。 这些实验将通过一个额外的实验来补充，该实验旨在分离每个营养级的选择和互补效应。 总之，这些研究将提供物种多样性和地上和地下食物网如何相互作用，以控制北方土壤中碎屑生物量的积累的清晰的理解。 了解地下碎屑的动态是很重要的，因为碳平衡模型往往忽略地下碎屑C的储存，而且可能大于地上的储存。 通过比较一系列林龄和管理活动的多样性和组成的变化，我将能够进一步概括森林管理何时对生态系统功能产生最大影响。 通过划分选择和互补效应，我也将能够确定何时需要额外的精细过滤器保护策略[如相对较强的选择效应所示]来维持管理森林中的生态系统功能。

Relating between biodiversity to ecosystem function continues to gain relevance in ecology. Increasing diversity is thought to affect ecosystem functions through both selection [also termed 'sampling' effects] and complementarity effects which partition the effects of species with superior performance from those of synergistic species mixtures. Critical ecosystem functions such as decomposition of detrital biomass in boreal forests are further regulated by interactions between above- and below-ground communities. I will compare diversity of saproxylic arthropods and fungi between surface and buried CWM across 1) mixedwood and black-spruce dominated chronosequences [spanning >300 years] and 2) managed jack-pine stands where CWM volume has been experimentally altered through forest harvesting. I will then perform a series of controlled experiments where species and functional group diversity is increased sequentially at three trophic levels [wood decaying fungi, fungivores and predators] and overall effects on wood decomposition rate are measured. These experiments will be complemented by an additional experiment designed to separate selection and complementarity effects at each trophic level. Taken together these studies will provide clear understanding of how species diversity and above- and below-ground food webs interact to control the accumulation of detrital biomass in boreal soils. Understanding below-ground detrital dynamics is important as below-ground stocks of detrital C are often neglected in carbon balance models and can be greater than those found above-ground. By comparing changes in diversity and composition across a range of stand ages and management activities I will be able to further generalize when forest management will have greatest effects on ecosystem functions. By partitioning selection and complementarity effects, I will also be able determine when additional fine filter conservation strategies [as indicated by relatively strong selection effects] will be required to maintain ecosystem functions in managed forests.