Göttingen, Univ., Diss., 2002. / Computerdatei im Fernzugriff.

Göttingen, Univ., Diss., 2002. / Computerdatei im Fernzugriff.

Göttingen, Universiẗat, Diss., 2002.

Casuarina equisetifolia L. is a noxious plant species known to be invasive in the West Indies. Not much is known about its impact on its host environment. This study’s objective was to quantitatively compare physical and chemical soil differences between sites dominated by and devoid of Casuarinas. This study also conducted growth chamber experiments to determine potential for allelopathy. It was demonstrated that sites dominated by Casuarinas differed significantly in K, P, organic matter, and leaf litter depth. Application of Casuarinas leachate showed reduction in germination of radish and bean seeds by at least 32% and 70%, respectively. Once germinated no growth suppression of seedlings were observed with applications of Casuarinas leachate. Investigation with liquid chromatography mass spectrometry (LC-MS) revealed the potential presence of the allelochemical chalepin. This research demonstrates that Casuarinas have the potential to modify their host environment and therefore perpetuate their existence as a noxious invasive species.

No description available.

Urban development and human encroachment on the natural habitats along the coastline of Florida combined with invasive exotic pressures have resulted in the fragmentation and degradation of habitat quality within Broward County. Native habitats have been significantly altered and fragmented to a fraction their previous size. With loss of habitat area and quality, isolation of breeding populations and anthropogenic pressures, it is important to determine species composition and habitat utilization in order to conserve the remaining biological diversity. It was the intent of this study to determine the small mammal species’ population structure and habitat utilization by season in the four sampled habitats. Previously undocumented species and/or extralimital populations were predicted prior to sampling. John U. Lloyd Beach State Park in Dania Beach, Florida is an understudied location for small mammals. This study surveyed four terrestrial habitats for small mammal species using live trapping and mark/recapture techniques. Data were collected monthly over the span of thirteen months to determine habitat use from maritime hammock, mangrove swamp, coastal dune and ruderal habitat types to determine species composition and mass of individual captures and recaptures. Trapping (3749 trap nights) produced twenty-four captures (including recaptures) in two of the four habitat types: maritime hammock and coastal strand. No animals were captured in the mangrove swamp or ruderal habitats, both of which were dominated by invasive Australian pine (Casuarina equisetifolia) monocultures. Post study, a large habitat restoration project restored the habitats impacted by invasive exotic flora. This survey serves as a baseline for small mammals in the park, documenting the pre-restoration habitat use and species composition. Future study to determine changes in species composition post-restoration is recommended.