Research into the sensitivity of fragmentation metrics

在景观生态学和森林清查中，森林和景观的破碎化正在用破碎化尺度（景观尺度）加以量化。这些指标基于可测量的属性，如面积和周长。它们被用作大面积生物多样性评估和监测的业务指标。碎裂度的计算对以下因素很敏感：（1）空间分辨率（水平和垂直）;（2）类别;（3）边缘定义;（4）地形。有人认为，碎片化指标需要解释的背景下，他们对这些factors. Objective的敏感性，拟议的研究是提高碎片化指标的可解释性，通过分析他们对上述因素的敏感性。这在比较指标（来自不同区域或来自同一区域不同时间点的指标）时特别重要。在拟议的研究中，首先将进行模拟研究的理论几何的理由。然后，重点关注哥斯达黎加支离破碎的森林景观，将利用遥感图像（包括德国航天中心新的德国雷达卫星TerraSAR-X的数据）和实地数据对这些景观进行分析。将阐述应用实例（与研究地点内生物多样性数据的关系;以及对破碎化指标时间序列的分析），并商定与哥斯达黎加伙伴（技术、工业和经济研究中心和联合国协会）密切合作。这项研究有一个方法重点;研究结果适用于任何土地覆被类别。

Forest- and landscape fragmentation is being quantified by fragmentation metrics (landscape metrics) in landscape ecology and forest inventory. These metrics base upon measurable attributes such as area and perimeter length. They are used as operational indicators for large area biodiversity assessment and monitoring. Calculation of fragmentation metrics is sensitive to factors like (1) spatial resolution (horizontal and vertical), (2) class- and (3) edge-definition and (4) topography. It is contended that fragmentation metrics need to be interpreted in the context of their sensitivity to these factors.Objective of the proposed study is to improve the interpretability of fragmentation metrics through analysing their sensitivity to the above factors. This is of particular importance when metrics are to be compared (either from different regions or from the same region at different points in time). In the proposed study, at first simulation studies will be carried out on theoretical geometrical grounds. Then, focus is then on fragmented forest landscapes in Costa Rica that will be analysed from remote sensing imagery (including DLR data of the new German radar satellite TerraSAR-X) and field data. Application examples will be elaborated (relationship to biodiversity data within the study sites; and analysis of time series of fragmentation metrics).Close cooperation with Costa Rican partners is (CATIE and UNA) is agreed. The study has a methodological focus; findings apply to any land cover class.