Quantification of diet variability in a stream amphipod: implications for ecosystem functioning
Quantification of diet variability in a stream amphipod: implications for ecosystem functioning
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溪流片脚类饮食变异的量化：对生态系统功能的影响
DOI：
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发表时间：
2008
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通讯作者：
O. Dangles
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文献类型：
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作者：
V. Felten;G. Tixier;F. Guérold;V. Billy;O. Dangles
许多论文将凋落叶分解的速度与伽马酰胺的存在/丰度联系起来。然而，最近的研究表明，Gammarus sp.可能具有很高的饮食多样性（如动物，苔藓，藻类）。在这种情况下，我们量化了Gammarus fossarum的饮食，以突出和统计考虑许多作者通过观察而肯定的东西。为此，我们使用了最近描述的多变量分析，称为%PCA，它允许调查处理饮食成分的数据。体型和微生境类型是控制饮食中几个参数的高度显著变量。结果表明，食物的大小和捕食行为随体型的增加而增加，而食物的种类和丰度与微生境类型有关。此外，无论微生境类型如何，体型对专业化都有显著影响。生态位重叠也随着体型两两差异的增加而减少，从而允许来自不同阶段的个体聚集在一起。我们的结论是，G. fossarum表现出机会主义行为，这使得有必要重新考虑γ γ“切碎”活动的重要性，以准确评估流功能和能量和物质的通量/再分配（凋落叶分解）。本文从个体和种群两个层面探讨了黄颡鱼的功能性摄食群体成员关系。
Numerous papers associate the rate of leaf litter decomposition with the presence/abundance of gammarids. However, recent studies showed that Gammarus sp. may have high diet diversity (as animals, moss, algae). In this context, we quantify the diet of Gammarus fossarum to highlight and statistically consider what many authors affirmed rather by observation. To this end, we used a recently described multivariate analysis, called %PCA, which allows investigating data dealing with diet composition. Body size and microhabitat type were revealed highly significant variables governing several parameters of the diet. In particular, our results show that food item size and predatory behaviour increased with body size, whilst the type and abundance of food consumed was related to microhabitat type. Furthermore, body-size had a significant effect on specialisation whatever the microhabitat type. Niche overlap also decreased as pairwise differences in body-size increased, allowing the aggregation of individuals from different instars. We conclude that G. fossarum exhibit an opportunistic behaviour, which makes necessary to reconsider the importance of gammarid "shredding" activity to accurately assess stream functioning and flux/ redistribution of energy and matter (leaf litter breakdown). We discuss the functional feeding group membership of G. fossarum at the individual and population level.