Die Effekte von Landnutzung und struktureller Heterogenität auf Biodiversität: eine neue Bewertungsmethode mittels kosteneffektiver Fernerkundung und feinskaliger Musteranalysen

基于典型的高分辨率航空图像，我们以前已经表明，森林下层维管植物的生物多样性确实与树冠空隙的结构复杂性密切相关。这是可行的，因为“林下光照可以作为一个单一的综合因素，对不太明显的小气候变化进行分组”(Barbier等人。2008年)。然而，到目前为止，当土壤或气候差异等跨区域影响发挥作用时，林下生物多样性如何对现有的缺口结构做出反应尚不清楚。同样，人们对不同树种组成对林下植物对林隙光反应的混杂影响知之甚少，也不知道必须有多大的样本面积才能在林隙结构和生物多样性之间产生有意义的相关性。在这个项目中，我们打算基于德国三个地区1500个格子地块的植被记录的正射影像的GAP信息来调查这些问题。我们将利用土壤数据和三个探索实验室中这些网格样地的森林清查中的树木记录，详细调查林下物种多样性与林隙结构之间的关系。这一分析将有助于更好地了解林隙结构、土壤和树种组成对林下植物多样性的相对重要性。作为进一步的成果，我们的生物多样性评估方法可能被用作成本效益高的“粗过滤方法”进行保护，因为大多数森林管理部门都有正射影像资料。我们认为这是实质性的好处，因为不断升级的生物多样性丧失需要对土地利用对多样性的影响进行有效的大规模评估。

Based on exemplary high-resolution aerial images, we have previously shown that biodiversity of vascular plants in the forest understorey does strongly correlate with the structural complexity of canopy gaps. This is feasible because “understorey light can be used as a single synthetic factor grouping less apparent microclimatic variations” (Barbier et al. 2008). However, so far it is unknown how understorey biodiversity responds to available gap structures when confounding trans-regional effects such as differences in soil or climate come into play. Likewise, little is known about the confounding effects from different tree species compositions on the response of understorey plants to gap light or how large sample areas must be to cause meaningful correlations between gap structures and biodiversity. In this project we intend to investigate these questions based on gap information from orthophotos that are available for vegetation recordings of 1500 grid plots in three regions of Germany. We will use soil data and tree recordings from forest inventories of these grid plots in the three exploratories to investigate in detail the relationship between understorey diversity and gap structure. This analysis will help to better understand the relative importance of gap structure, soil, and tree species composition for understorey plant diversity. As a further deliverable, our assessment method of biodiversity may be used as a cost-effective ‘coarse-filter approach’ to conservation because orthophotos are available at most forest administrations. We consider this as substantial benefit because the escalating loss of biodiversity requires efficient large-scale evaluations of land-use impact on diversity.