Korb Judith, Linsenmair Karl Eduard
Theodor Boveri Institut, Lehrstuhl für Tierökologie und Tropenbiologie, Am Hubland, 97074, Würzburg, Germany.
Oecologia. 2001 May;127(3):324-333. doi: 10.1007/s004420000597. Epub 2001 May 1.
Little is known about processes regulating population dynamics in termites. We investigated the distribution of mound-colonies of the fungus-cultivating termite Macrotermes bellicosus (Smeathman) in two habitats in the Comoé National Park (Côte d'Ivoire) with nearest-neighbour analysis differentiating between different age classes. These results were compared with ecological data on processes influencing population dynamics. High mound densities were recorded in shrub savannah while only a few mounds were found in gallery forest. Mounds were distributed randomly in both habitats when all mounds were considered together, and when inhabited and uninhabited mounds were treated separately. However, distinctive non-random patterns were revealed in the savannah when we distinguished between different age classes. Small, young colonies were aggregated when they coexisted with larger, older colonies, which were more regularly distributed. This indicates that the distribution of older colonies is influenced by intraspecific competition whereas that of younger colonies is influenced by opposing factors that lead to aggregation. This is in accordance with ecological data. Food is a limiting resource for large colonies, while patchily distributed appropriate microclimatic conditions seem to be more important for young colonies. Colonies that had formerly coexisted (i.e. living colonies and recently dead colonies) showed aggregated, random and regular distribution patterns, suggesting several causes of mortality. Colonies that had never had contact with each other were randomly distributed and no specific regulation mechanism was implicated. These results show that different age classes seem to be regulated by different processes and that separation between age classes is necessary to reveal indicative spatial patterns in nearest-neighbour analysis.
关于调节白蚁种群动态的过程，我们所知甚少。我们利用最近邻体分析，区分不同年龄等级，调查了科莫埃国家公园（科特迪瓦）两个栖息地中培养真菌的白蚁Macrotermes bellicosus（斯米斯曼）蚁丘群落的分布情况。这些结果与影响种群动态过程的生态数据进行了比较。在灌木稀树草原中记录到高蚁丘密度，而在长廊林里只发现了少数蚁丘。当把所有蚁丘一起考虑时，以及分别处理有蚁群居住和无蚁群居住的蚁丘时，两个栖息地中的蚁丘都是随机分布的。然而，当我们区分不同年龄等级时，稀树草原中呈现出独特的非随机模式。当小的、年轻的蚁群与大的、年长的蚁群共存时，小蚁群聚集在一起，而大蚁群分布更规则。这表明年长蚁群的分布受种内竞争影响，而年轻蚁群的分布受导致聚集的相反因素影响。这与生态数据相符。食物是大蚁群的限制资源，而分布不均的适宜小气候条件对年轻蚁群似乎更重要。以前共存的蚁群（即现存蚁群和最近死亡的蚁群）呈现出聚集、随机和规则的分布模式，这表明有多种死亡原因。从未相互接触过的蚁群随机分布，没有涉及特定的调节机制。这些结果表明，不同年龄等级似乎受不同过程调节，在最近邻体分析中，区分年龄等级对于揭示指示性空间模式是必要的。
