Dissertation Research: The Influence of Landscape Heterogeneity on Insect Population Dynamics

9410872 Kareiva当今世界的生态景观越来越多地表现为棋盘状的不同栖息地的马赛克，包括城市、农业和自然环境。生态学家还没有设计出一种普遍的理论来确定这些影响，更重要的是，混合景观可能对居民人口产生影响背后的机制。研究人员选择进行一项田间试验，将非作物植被(例如杂草)纳入农田。实验设计还包括不同规模的作物和杂草的不同混合物，以便研究人员可以确定此类混合物在各种一般农田情景中的有用性。这些实验现场测试的数据将被合并到不同的数学模型中，以期阐明在现场运行的机制。这种经验主义和理论的结合将导致一个协议，在任何给定的环境下，确定混合景观类型如何以及在多大范围内可能影响昆虫种群。将实地实验中获得的数据纳入数学模型将推广到许多不同的现实生活场景中，在这些场景中，生物体在不同的景观组合中移动。鉴于目前景观碎片化加剧和人口压力增加的趋势，任何这种结合农业生产和自然植被的一般指导方针都应该是一项重要的贡献。

9410872 KAREIVA The ecological landscape in today's world is becoming increasingly characterized by a checkerboard-like mosaic of diverse habitats encompassing urban, agricultural, and natural environments. Ecologists have yet to devise a general theory pinpointing the effects, and more importantly, the mechanisms behind the effects that mixed landscapes may have upon resident populations. The investigators have chosen to conduct a field experiment in which non-crop vegetation (e.g. weeds) is incorporated into a crop field. The experimental design includes varying mixtures of crop and weed at different scales as well, so that investigators can determine the usefulness of such mixtures in a variety of general farmland scenarios. The data from these experimental field tests will be incorporated into different mathematical models, in the hopes of elucidating the mechanisms operating in the field. This mix of empiricism and theory will lead to a protocol for determining, in any given setting, how and at what scale mixing landscape types may affect insect populations. Incorporating data obtained in field experiments into mathematical models will generalize to many different real-life scenarios in which organisms move through combinations of diverse landscapes. Any such general guidelines combining agricultural production and natural vegetation should be an important contribution ln light of the current trend towards increasing landscape fragmentation as well as increasing population pressure.