Doctoral Dissertation Research: Multi-Scale Investigation of Environmental and Human Influences on the Distribution of Birds in the Western Amazon

生物地理多样性的假想原因包括生态条件的时空变异性，如气候、土壤类型、地形、物种间的竞争、物种的扩散能力和历史气候变化。额外的复杂性是由人类影响造成的，包括狩猎、农业和林业。这项博士论文研究项目将在亚马逊盆地西部的不同森林景观中使用标准化的生物调查，以测试这些不同因素对鸟类物种组合地理分布的相对影响。用于测试假设的多样性原因的可衡量指标包括植物种类组成、森林的结构特征、海拔、相对于主要扩散屏障(河流)和假设的生物地理区域(生态区域)的位置、地点之间的距离以及相对于当地人类住区和区域市场的可达性。植物种类组成对植被物理结构的相对影响是研究鸟类栖息地选择的一个特别有趣的问题。对地方、景观和区域尺度的关联分析将检验空间尺度的影响。将调查所有鸟类物种的空间格局以及物种亚群的空间格局。对生态和系统发育定义的物种群体进行审查，将使人们能够以不同群体对特定影响作出反应的方式来确定多样性。例如，狩猎压力预计会对大型物种造成不成比例的影响。如果特定的物种组反映了在鸟类群落中观察到的更普遍的模式，则这些组可被确定为可提高未来调查工作效率的指标组。这项研究的结果可能会识别更复杂的情况，其中不同的鸟类物种群体在不同的空间尺度上对不同的因素做出反应。尽管如此，确定鸟类种类组合分布与解释因素之间的强大关联可能允许推断大范围内的群落区别性格局，这取决于新的调查数据的验证。在亚马逊盆地，关于景观和区域尺度生物多样性空间分布的基本信息相对稀缺，因此景观的生物地理分类是本研究的基本目标。此外，这项研究采取的综合方法将有助于通过定量评估特定地区的生物多样性状况，作为多种文化和自然过程在多个空间尺度上运行的结果，从而促进生物地理学理论的发展。多种形式的生物地理信息的产生和整合也可以在可持续文化景观的发展中发挥关键作用，因为具有生物特色的地方具有独特的保护价值和资源利用潜力。为保护和发展规划提供信息的地理信息在增长和景观变化迅速的地区特别有价值，例如该项目的研究区域位于秘鲁亚马逊的伊基托斯市周围。作为博士论文研究改进奖，该奖项还将提供支持，使有前途的学生建立一个强大的独立研究生涯。

Among the hypothesized causes of biogeographic diversity are spatial and temporal variability in ecological conditions, such as climate, soil type, topography, competition among species, dispersal abilities of species, and historical climate changes. Additional complexity is contributed by human influences, including hunting, agriculture, and forestry. This doctoral dissertation research project will use standardized biological surveys across variable forest landscapes in the western Amazon basin to test the relative influence of these different factors on the geographical distribution of bird species assemblages. Measurable proxies used to test hypothesized causes of diversity include plant species composition, structural characteristics of the forest, elevation, location relative to major dispersal barriers (rivers) and hypothesized biogeographic zones (ecoregions), distances among sites, and accessibility relative to local human settlements and regional markets. The relative influence of plant species composition vs. the physical structure of vegetation is of particular interest for investigating habitat selection in birds. Analysis of associations at local, landscape, and regional scales will test effects of spatial scale. Spatial patterns will be investigated for all bird species together and for subsets of species. Examining ecologically and phylogenetically defined species groups will allow the identification of diversity in the ways different groups may respond to particular influences. For example, hunting pressure is expected to disproportionately affect large-bodied species. If particular species groups reflect patterns observed more generally in the bird community, those groups may be identified as indicator groups that can improve the efficiency of future survey work. Results of this study may identify more complex situations in which different groups of bird species respond at different spatial scales to different factors. Nonetheless, the identification of robust associations between bird species assemblage distributions and explanatory factors may allow the inference of patterns of community distinctiveness across wide areas, subject to validation with new survey data.Basic information about the spatial distribution of biodiversity at landscape and regional scales is relatively scarce in the Amazon basin, and the biogeographic classification of landscapes is therefore a basic goal of this research. Furthermore, the integrative approach taken by this research will help advance biogeographic theory by quantitatively assessing the biodiversity status of particular places as outcomes of multiple cultural and natural processes operating at multiple spatial scales. The production and integration of multiple forms of biogeographic information also can play a key role in the development of sustainable cultural landscapes, because biologically distinctive places have distinctive conservation values and resource use potentials. Geographic information that informs conservation and development planning is of particular value in areas where growth and landscape change are occurring rapidly, such as this project's study area surrounding the city of Iquitos in the Peruvian Amazon. As a Doctoral Dissertation Research Improvement award, this award also will provide support to enable a promising student to establish a strong independent research career.