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G.R. Guntenspergen

Publications and source records attributed to G.R. Guntenspergen.

21 records · Page 2Linked to original sources

Global change and submerged aquatic vegetation research

Communities of submerged aquatic vegetation (SAY) are important components of many freshwater, brackish, and marine aquatic ecosystems. They prevent erosion by baffling the impacts of waves, especially from storms. These aquatic plant communities remove nutrients and other pollutants from river and runoff inputs to coastal areas, preventing their entry into surrounding waters. They provide nursery habitat for fish, shrimp, and other species, as well as forage for wintering waterfowl and endangered species such as sea turtles and manatees. Unfortunately, not only have the distribution and abundance of seagrasses in the northern Gulf of Mexico declined precipitously during the past 50 years, most notably from widespread deterioration of water quality, but submerged aquatic plant communities are also susceptible to long-term environmental changes that are predicted to accompany global climate change.

Fact Sheet↗

The interactive effects of herbivory and fire on an oligohaline marsh, Little Lake, Louisiana, USA

Herbivory and fire have been shown to affect the structure and composition of marsh communities. Because fire may alter plant species composition and cover, and these alterations may have an effect on herbivore populations or foraging patterns, an interactive effect of herbivory and fire may be expected. In this study, the effects of fire and vertebrate herbivory in a Louisiana oligohaline marsh were studied using small, controlled burns and animal exclosures. Mean total biomass was nearly 2 times greater in the plots protected from herbivory than in the plots subject to natural herbivory. Additionally, mean total biomass was over 1.5 times greater in the plots that remained unburned than in those that were burned. Two dominant perennial species, Spartina patens and Scirpus olneyi , were negatively affected by herbivory, but two annual sedges, Cyperus flavescens and Cyperus odorata , were positively affected. Burning reduced the aboveground biomass of Spartina patens and Bacopa monnieri . No species increased in biomass as a result of fire. No significant differences were found in species richness between herbivory treatments or between fire treatments. Although both herbivory and fire were found to cause significant changes in the vegetation, the interaction between herbivory and fire was not found to produce any significant effects in any test conducted.

Louisiana↗