Abstract

Pollen and honey resources composing the diet of Tetragonisca angustula fiebrigi Schwarz were assessed using pollen analysis of wild colonies sampled in two kinds of native dry forests of the Chaco region. Different measurements: direct pollen count, relative volume, diversity and evenness indices, value of importance of species (SI), and index of relative importance (IRI) were compared. The IRI identified the most important pollen resources as Prosopis (IRI = 1619), Schinopsis type (IRI = 1578), Trithrinax schizophylla (IRI = 972) and Capparicordis/Sarcotoxicum (IRI = 587), and according to SI the honey resources were Schinopsis type (SI = 117.41), Maytenus type (SI = 101.89), Prosopis (SI = 86.47) and Ziziphus mistol (SI = 50.93). The absolute pollen analysis of honey revealed that all samples were rich in pollen grains. Floral resources were most homogeneously foraged during spring and summer when a high number of flowerings were available and the highest temperatures were recorded. These optimal conditions for bee foraging activity also allowed for the highest diversity indices in these seasons. However, heterogeneous foraging and low diversity were detected during winter and autumn. Most pollen and honey resources belonged to generalised small flowers of diverse plant lineages. The IRI was more comprehensive to identify the most important pollen resources than the commonly used direct pollen count, as it also includes relative volume and frequency of occurrence, and SI was the most thorough for studying the honey resources. This study provides helpful information for sustainable meliponiculture and forest conservation.

摘要

花粉和蜂蜜资源构成了Tetragonisca fiebrigi Schwarz的饮食，使用花粉分析对在查科地区两种天然干燥森林中取样的野生菌落进行了评估。不同的测量值：直接花粉计数、相对体积、多样性和均匀度指数、物种重要性值 (SI) 和相对重要性指数 (IRI) 进行了比较。IRI 确定最重要的花粉资源为Prosopis (IRI = 1619)、Schinopsis type (IRI = 1578)、Trithrinax schizophylla (IRI = 972) 和Capparicordis / Sarcotoxicum (IRI = 587)，根据 SI，蜂蜜资源为Schinopsis类型（SI = 117.41），Maytenus型 (SI = 101.89)、Prosopis (SI = 86.47) 和Ziziphus misol(SI = 50.93)。蜂蜜的绝对花粉分析显示所有样品都富含花粉粒。花卉资源在春季和夏季采食最均匀，此时有大量开花，温度最高。这些蜜蜂觅食活动的最佳条件也使这些季节的多样性指数最高。然而，在冬季和秋季检测到异质觅食和低多样性。大多数花粉和蜂蜜资源属于不同植物谱系的广义小花。IRI比常用的直接花粉计数更全面地识别最重要的花粉资源，因为它还包括相对数量和发生频率，而SI是研究蜂蜜资源最彻底的方法。