Comparative analysis of vegetation in the habitat of bonobos and chimpanzees using Landsat image.

利用卫星资料，通过树木的数量普查，我们可以区分出几种植被类型，包括原始林、次生林和沼泽林。这些信息对于分析黑猩猩和倭黑猩猩对植被的利用是有用的。陆地卫星数据和树木普查之间的比较，使估计的植被类型的一部分，我们不能进行树木普查的家园范围。因此，这种方法似乎是有用的栖息地利用的分析物种的家域太大，覆盖的实际植被普查。我们还发展了一种改进的巢计数方法，用于估计黑猩猩的密度。通过这种方法，我们可以在较短的研究时间内准确估计黑猩猩的密度及其栖息地利用的季节变化。利用这些方法，我们分析了黑猩猩的栖息地利用在Kalinzu森林，乌干达，Ugala地区和Lukwa地区在坦桑尼亚，倭黑猩猩在Wamba地区和Hongo地区在刚果民主共和国。我们发现，在不同植被类型的地区，黑猩猩和倭黑猩猩的密度有很大的差异，而且这些动物在不同的季节会大幅度地改变它们的活动范围。我们还发现，在一个家园范围内不同植被类型的组合增加了黑猩猩和倭黑猩猩的密度。基于这些信息，我们可以确定一些重要的因素影响黑猩猩和倭黑猩猩的栖息地利用，并可以在未来的研究中检查其栖息地利用的种间和种内差异。在这个研究项目中，我们把重点放在我们实际访问和进行调查的地区。然而，这项利用地球资源卫星数据的研究开辟了一条在没有实际植被普查的情况下估计更广泛地区黑猩猩和倭黑猩猩密度的途径。

By using the landsat data and enumerating census of trees, we could distinguish several types of vegetation, including primary forest, secondary forest, and swamp forest. This information was useful for the analysis of vegetation use of chimpanzees and bonobos. The comparison between the landsat data and tree census enabled to estimate the vegetation type of the part of the home range for which we could not carry out the tree census. Thus this method appeared to be useful for the analysis of habitat use of the species whose home range is too large to cover by the actual vegetation census. We also developed an improved method of nest count for the estimation of density of chimpanzees. By this method, we could estimate accurate density of chimpanzees and the seasonal changes of their habitat use in a shorter period of research. Using these methods, we analyzed the habitat use by chimpanzees in the Kalinzu Forest, Uganda, Ugala area and Lukwa area in Tanzania, and bonobos in Wamba area and Hongo area in Democratic Republic of Congo. We found that the density of chimpanzees and bonobos are much different between the areas with different vegetation types, and that these animals largely shift their home ranges in different seasons. We also found that the combination of different vegetation types in a home range increases the density of chimpanzees and bonobos. Based on these information, we can identify some important factors influencing the habitat use by chimpanzees and bonobos, and can examine the inter and intra-specific differences in their habitat use in future studies. In this study project, we focused on the area where we actually visited and carried out the survey. However, this study using the landsat data opened a way to estimate the density of chimpanzees and bonobos in the wider area without the actual vegetation census.