| Abstrakt: |
1.Riparian management is becomingly increasingly recognized as an important tool for reducing harvesting impacts on plantation forest streams. To provide information for a riparian management decision support system, this study investigated effects of riparian tree type (plantation Pinus radiata D. Don versus four native species) on the development of epixylic biofilms, and colonization and feeding by invertebrates on wood at two contrasting stream sites in the central North Island, New Zealand.2.Electron micrographs revealed a diverse microflora colonizing all wood types, which generally had similar ergosterol concentrations, microbial activity and algal biomass after 12 years immersion.3.Wood type (pine versus native) did not have a significant effect on densities of total invertebrates or dominant taxa. Percentage abundance of some dominant invertebrate groups differed between wood species, apparently in relation to surface complexity, but overall physical habitat differences appeared to override any effects of wood type on community composition.4.The mass of fine particulate material produced by larvae of the conoesucid caddis fly, Pycnocentria funerea McLachlan, differed significantly among wood species, but this was not related to whether the wood was from native trees or plantation pine.5.Overall, the results indicate that local variations in habitat heterogeneity and differences in wood surface texture were more important than wood type in influencing epixylic biofilm development, and utilization by invertebrates. Alien pine wood generally provided habitat conditions and trophic resources during initial decomposition that were within the range of variation of native wood species expected to colonize riparian planting set-backs in northern New Zealand pine forests. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR] |
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