生态条件的多样性变化对蜜蜂生存的影响

目的在云南省罗平县油菜花期，比较西方蜜蜂不同放蜂密度下东方蜜蜂采集行为的变化，以期从食物资源竞争的角度为合理保护中国本土蜂种和维持植物群落结构及其稳定性提供科学依据。方法调查九龙镇和大水井乡主干道上的西方蜜蜂放蜂密度，根据放蜂密度选择6个试验点放置供试东方蜜蜂蜂群；观测试验点农田、山林两种生境中访花的东方蜜蜂和西方蜜蜂数量以及东方蜜蜂访花频率、单花采集停留时间；调查试验点周围3 km内的显花植物种类，采集植物花粉与东方蜜蜂花粉团，计算蜂花粉团中不同花粉的比例；分析西方蜜蜂不同放蜂密度对东方蜜蜂采集行为和粉源植物利用的影响。结果油菜盛花期，山林中访花的东方蜜蜂数量比例大于农田样方；油菜末花期，西方蜜蜂蜂场大量撤离后，农田样方中访花的东方蜜蜂数量比例明显增加；农田样方中东方蜜蜂的平均访花频率与其周围3 km范围内的西方蜜蜂数量(密度)呈显著的正相关关系，单花采集停留时间与其周围3 km范围内的西方蜜蜂数量(密度)呈显著的负相关关系；山林生境中西方蜜蜂放蜂密度大的试验点，东方蜜蜂的访花频率高，单花采集停留时间短；各试验点东方蜜蜂采集的花粉团总数量与其周围3 km范围内的西方蜜蜂数量(密度)呈负相关关系；油菜花期东方蜜蜂采食零星粉源植物花粉的比例与其周围3 km范围内的西方蜜蜂数量(密度)呈显著的正相关关系。结论西方蜜蜂放蜂密度对东方蜜蜂的采集行为有显著影响，且西方蜜蜂放蜂密度越大，东方蜜蜂的食物生态位越偏离农田中的大宗蜜源(油菜)，其采集区域朝着山林转移的趋势越明显。

Honey bee pathology: current threats to honey bees and beekeeping

PurposeIn this study, we compared the changes of the foraging behavior of Apis cerana under various colony densities of A. mellifera at Luoping in the florescence of Brassica campestris. In order to provide scientific basis for rational protection of native bee species and maintenance of plant community structure and stability from the perspective of competition for food resources.MethodSix field sites from Jiulong Town and Dashuijing Town were selected for placing experimental eastern honeybee colony based on the previous survey of colony density of western honeybee. Firstly, the number of foragers for these two honeybee species was counted, and the frequency of visiting flowers and the average settling time for A. cerana was recorded under farmland and montane habitat of these experimental sites. Secondly, species of phanerogam within three kilometers were investigated, and anthers of phanerogam, pollen grains of A. cerana were collected to calculate the proportion of various pollens. Finally, effects of various colony density of A. mellifera on the foraging behavior and pollen collecting of A. cerana were estimated.ResultsThe quantitative proportion of A. cerana in the mountain forest was higher than that in farmland quadrats for six experimental sites in the flourishing florescence, but the quantitative proportion of A. cerana in farmland quadrats was increased significantly after A. mellifera apiaries evacuating from Luoping at the end of flowering stage. There were significant positive correlation between the average visiting frequency of A. cerana and colony densities of A. mellifera within 3 km, and the significant negative correlation between the average settling time of A. cerana and colony densities of A. mellifera within 3 km; with the increase of the colony densities of A. mellifera in the mountain forest, the visiting frequency of A. cerana increased, the settling time of A. cerana reduced; there were negative correlation between the total number of pollen loads collected by A. cerana and colony densities of A. mellifera within 3 km; there were significant positive correlation between the percentage of wild pollens collected by A. cerana and colony densities of A. mellifera within 3 km.ConclusionThe colony density of A. mellifera has a significant effect on the foraging behavior of A. cerana. With the increase of the colony density of A. mellifera, the more the food niche of A. cerana deviate the source of large amount of pollen plants in farmland, and the trend which foraging area of A. cerana was shifted from the farmland to the mountains forest become more obvious.