The use of assisted succession to restore the globally imperiled dwarf pine-oak forests of the New Jersey Pinelands: An investigation of the functional and structural recovery of an abandoned gravel pit.

摘要

Over the last 65 years, military operations at the New Jersey Air National Guard's Warren Grove Gunnery Range (WGGR) have scarred and fragmented pristine pine barren habitats within the Pinelands National Reserve. The Pinelands National Reserve in Central and Southern New Jersey contains one of the largest continuous areas of pine barren ecosystems in the world, including the globally imperiled dwarf pine-oak forests known as the pine plains. Because the pine plains are ecologically important and no specific recommendations for restoring pine plain habitats exist, I designed an investigation that would examine and evaluate past approaches to restoring pine plains communities, identify specific revegetation strategies that complement natural processes, and experimentally determine the environmental constraints for reintroducing native communities. This investigation also quantified how highly disturbed pine plains system recover structurally and functionally from mechanical disturbance. Furthermore, this work will help to formulate an understanding of some of the ecological processes driving succession in these nutrient limited, fire adapted ecosystems.I found that after 10 to 20 years of restoration, previous attempts to reforest degraded pine plains habitats produced monocultures of pines that were similar to reference plots in terms of total plant cover but were dissimilar in terms of plant community structure and composition. As a result of these data, an alternative approach to reforestation was investigated. This approach used native colonizing grasses to ameliorate dysfunctional soil conditions, facilitate natural recovery and catalyze successional processes. An abandoned gravel pit restored with native grasses showed recovery patterns that were both structurally and functionally similar to those of a mechanically disturbed site recovering naturally by spontaneous succession. The establishment of native grasses during restoration also improved when soil amendments created ideal germinating conditions. This investigation demonstrated that using assisted succession to restore mechanically disturbed, pine plains habitats in the New Jersey Pinelands is superior to other previously applied reforestation methods.