Titelangaben
Stadler, Bernhard ; Michalzik, Beate:
Effects of phytophagous insects on micro-organisms and throughfall chemistry in forested ecosystems : herbivores as switches for the nutrient dynamics in the canopy.
In: Basic and Applied Ecology.
Bd. 1
(2000)
Heft 2
.
- S. 109-116.
ISSN 1439-1791
DOI: https://doi.org/10.1078/1439-1791-00016
Abstract
Phytophagous insects can have a severe impact on forested ecosystems. Their contribution to flows of energy and matter in non-outbreak situations is, however, less clear. Here we show that different types of phytophagous insects (aphids, lepidoptera larvae) in the canopies of trees can have similar effects on heterotrophic, epiphytic micro-organisms. Bacteria, yeasts and filamentous fungi thrived better on needles and leaves of herbivore infested trees. The biotic processes in the canopies of spruce and oak also affected throughfall chemistry. During periods of highest population densities and strong feeding activities, the concentrations of dissolved organic carbon (DOC) were higher in the throughfall sampled underneath infested trees while the concentrations of NH4-N and NO3-N were lower. It is concluded that phytophagous insects initiate cascading processes which affect the vertical flow of nutrients through the canopy of trees.