REU: Collaborative Research: Spatial Scaling and the Effects of Patch Mosaic Structure in Semiarid Ecosystems

生态系统由景观元素或斑块的镶嵌组成，这种斑块在许多空间尺度上都很明显。本研究将回答两个一般性问题：(1)景观格局在不同的空间尺度上是重复的吗？(2)景观镶嵌的斑块结构如何影响生态系统的动态和功能？第一个问题将通过确定半干旱生态系统中从1平方米到10平方公里的嵌套空间尺度上斑块(植被和受干扰地区以及节肢动物种群的分布)的分布模式来解决。通过在欧几里得和分维的尺度范围内确定镶嵌格局的重复程度，可以评估生态格局和过程独立于尺度运行的领域。这些领域设定了任何特定规模的研究结果可以外推到其他规模的限度。确定这些界限对于任何试图对景观马赛克中的生态模式或过程进行概括或比较不同生态系统调查结果的尝试都是至关重要的。为了解决第二个问题，将在精细到中等尺度上研究生物媒介(蚂蚁和甲虫)的运动模式，以确定它们与景观斑块镶嵌结构的关系。通过实验改变当地环境的斑块结构或动物的运动模式，这些生物在这些生态系统的斑块之间重新分配物质或能量方面可能发挥的作用将被估计。从某种程度上说，调查表明在一系列空间尺度上的模式是重复的，在精细尺度上进行的研究可以作为代表更大尺度的景观马赛克的“缩影”。因此，尽管微观和宏观尺度的系统可能在生物学上不同，但它们在模式上可能有统计上的相似性，从而允许开发程序，通过专注于宏观景观的精细模拟来实验研究景观中各元素之间的材料运动。这种性质的研究对于促进更好地管理干旱土地的自然资源可能具有至关重要的作用。此外，使用新的数学方法分析生态数据可能会产生一些迄今未被认识到的好处。

Ecosystems consist of mosaics of landscape elements or patches, and this patchiness is evident at many spatial scales. This research will answer two general questions: (1) Are landscape patterns repetitive over different spatial scales?, and (2) How does the patch structure of a landscape mosaic affect ecosystem dynamics and functions? The first question will be addressed by determining the patterns of distribution of patches (vegetation and disturbed areas as well as distributions of arthropod populations) at nested spatial scales ranging from 1 m2 to 10 km2 in semiarid ecosystems. By determining the degree of repetitiveness of mosaic patterns over ranges of scales in both Euclidean and fractal dimensions, one can assess the domains in which ecological patterns and processes operate independently of scale. These domains set the limits within which results from studies at any particular scale can be extrapolated to other scales. Establishing these limits is of critical importance to any attempts to derive generalizations about ecological patterns or processes in landscape mosaics or to compare the results of investigations of different ecological systems. To address the second question, the movement patterns of biotic vectors (ants and beetles) will be studied at fine to intermediate scales to determine how they relate to the patch- mosaic structure of the landscapes. By experimentally altering the patch structure of local environments or the movement patterns of animals, the roles that these organisms may play in the redistribution of materials or energy among patches in these ecosystems will be estimated. To the extent that the investigations indicate repetitiveness of patterns over a range of spatial scales, the studies conducted at fine scales may serve as a "microcosm" representing larger-scale landscape mosaics. Thus, although micro and macro-scale systems may differ biologically, they may share statistical similarities in patterns, allowing the development of procedures for experimentally investigating the movement of materials among elements in a landscape by focusing on fine-scale analogs of macro-landscapes. Research of this nature may be of fundamental importance in promoting the better management of the natural resources of arid lands. Additionally, there could be heretofore unrecognized benefits that would derive from the use of new mathematical approaches to the analysis of ecological data.