Browsing Scientia Discipulorum vol. 1 (2004) by Publication date
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Plant Community Succession Following Disturbances in a Pine Barren and Adjacent Hardwood ForestThe sandstone pavement barren and adjacent cobblestone formations in Clinton County, New York were created by the sudden release of water from glacial Lake Iroquois approximately 12000 ybp. Today, the barren is a rare ecological community type in New York State, dominated by jack pine, a species that can tolerate a water- and moisture-deficient soil. The soil in the cobblestone deposits supports hardwood trees such as northern red oak, sugar maple, red maple, and American beech. In January 1998, several days of freezing rain in the Northeast blanketed 10 million ha with 2 to 10 cm of ice. Two million ha of forests were severely affected, including the pine barren and adjacent forests in Clinton County, New York. This study investigated the effects of the ice storm and subsequent "restoration cuttings" on plant community succession in the pine barren and adjacent hardwoods. The William H. Miner Agricultural Research Institute, Chazy, New York owns the eight stands sampled in this study. Both disturbance types had dramatic effects on plant community structure. Nearly half of the hardwood trees were severely affected by the ice storm, but most survived through epicormic branching. Understory trees and regeneration proliferated beneath the temporary canopy gaps in the main canopy. Overstory species are represented in the regeneration size classes, with shade-tolerant species being most important. In the hardwoods, neither the ice storm or restoration cuttings caused plant community succession in the strict definition; the disturbances caused shifts in importance of species present at the time the disturbances occurred rather than a replacement of one plant community by another. In the pine barren, ice storm damage was especially intense, causing severe crown breakage in more than half of the pine trees. The majority of pine trees were killed by the ice storm and no pine seedlings were observed in the ice storm-damaged stands. Moderate amounts of jack pine regeneration (between 18000 and 24000 stems per hectare) were found in the areas treated with a restoration cutting. This amount of jack pine regeneration was considered sufficient to replace the original stand. The future of ice storm-damaged, uncut stands in the barren is not promising. Here, the majority of pine trees are standing dead stems and the regeneration, while sparse, is primarily red maple. Without silvicultural intervention, ice storm damaged areas of the barren will have a shift from dominance by jack pine to heath shrubs, especially black huckleberry. The restoration cutting showed that mechanical treatment, while not as effective as fire in regenerating jack pine, can bring about adequate amounts of jack pine regeneration, along with red maple, white birch and gray birch.
A Guide to the Zooplankton of Lake ChamplainThis key was developed by undergraduate research students working on a project with NYDEC and the Lake Champlain Monitoring program to develop long-term data sets for Lake Champlain plankton. Funding for development of this key was provided by, the Lake Champlain Basin Program through the U.S. Environmental Protection Agency (EPA) and the New York Department of Environmental Conservation (NYDEC). The key contains couplet keys for the major taxa in Cladocera and Copepoda and a picture key to the major Rotifer plankton in Lake Champlain. All drawings are original by Ian M. Ater. Many thanks to the employees of the Lake Champlain Research Institute and the NYDEC for hours of excellent work in the field and in the lab: Robert Bonham, Adam Bouchard, Trevor Carpenter, Virginia Damuth, Jeff Jones, Marti Kroll, Dustin Lewis, Shannon Margrey, Tracy McGregor, Stephanie Stone and David Welch. We greatly appreciate the time and effort of Paula Woodward and Francis Dumenci in helping to put this guide together.
Effects of an Ice Storm on Fuel Loadings and Potential Fire Behavior in a Pine Barren of Northeastern New YorkEcological effects of natural disturbances depend on the disturbance type, frequency, intensity and spatial scale. Of the major natural disturbances in the Northeast, ice storms are more frequent than fires or wind storms. Affecting nearly ten million hectares, the ice storm of January, 1998 was probably the most intense and widespread natural disturbance in the Northeast during the 20th Century. Some of the areas heavily impacted by this ice storm were sandstone pavement pine barrens of northeastern New York, among the rarest ecological communities in New York State. Jack pine (Pinus banksiana) is the dominant tree species in the barrens. Ice storm damage to pine trees resulted in estimates of woody debris averaging 18 tons/ac (40 tonnes/ha) at the eight sites sampled in this study. These unusually high fuel loadings increase the probability for catastrophic wildfire. Predictions of fire behavior and fire intensity in these ice storm-damaged stands were made using the TSTMDL subsystem of BEHAVE. Estimates of fire behavior in these ice storm-damaged stands include flame lengths between 10 and 17 ft (3 and 5 m) and fireline intensities between 900 and 2600 Btu/ft/sec (3175 and 9400 kW/m). Fires of these intensities would be very difficult to suppress and would cause adverse ecological effects, including destruction of seeds contained in the slash. Further research is necessary to customize fuel models used to predict fire behavior in northeastern forests affected by disturbances.
Decomposition Rates of Typha Spp. in Northern Freshwater Wetlands over a Stream-Marsh-Peatland GradientDecomposition rates in wetlands vary with the composition of the biotic community and the physical and chemical environment. Variations in the process of decomposition in turn affect the overall rate of nutrient cycling within the wetland, affecting both primary productivity and general wetland health. This short-term study took place in northern New York within the Little Chazy River watershed. The effects of wetland factors including nutrient status, dissolved oxygen, and pH value on decay rate were measured over a freshwater stream-marsh-peatland gradient. Litterbags were utilized and collected weekly from three separate sites within or near the Altona Flat Rock ecosystem. Soil and water parameters, as well as colonization by macroinvertebrates, were studied in order to link decay rates with specific wetland characteristics. Decomposition rates for Typha spp. were evaluated using the change in dry biomass, and percent nitrogen content of the plant litter. Dry biomass reduction took place most rapidly in the stream site and least rapidly in the peatland site, while fluctuations of percent nitrogen content did not show a distinct trend. A high level of dissolved oxygen corresponded to a higher decay rate, while a low pH value corresponded to a lower decay rate.