Klemow, Kenneth M. 1984. NATURAL REVEGETATION IN AN ABANDONED LIMESTONE QUARRY: A DEMOGRAPHIC PERSPECTIVE. Contributed poster: Symposium on Restoration Ecology: Theory and Practice. Madison, WI. Abstract: Conference Proceedings.
The least expensive approach to the restoration of surface mined sites is to simply allow plants to colonize and develop a community naturally. Rates of natural revegetation on such severely disturbed sites are typically low, however, necessitating expensive soil alterations and plant introductions. To better understand plant community development and the factors that retard its rate, a community of herbs naturally colonizing a 50-year old, abandoned limestone quarry near Syracuse, New York was examined from 1976 to 1981. Demographic attributes (germination, survival, and reproduction) of each species were assessed by mapping individuals in permanent quadrats. Substrate properties and weather conditions were also recorded and were related to population performance.
Each year, seedling emergence typically exceeded 50 m-2 for most of the species, indicating a potential for rapid population increase. Flushes of seedling emergence were generally followed by high rates of juvenile mortality, however. For four of the species (Melilotus alba, Erucastrum gallicum, Picris hieracioides and Asclepias tuberosa), seedling mortality was heavier during droughts than during periods of more abundant rainfall (Klemow & Raynal 1981, 1983, 1985). For Echium vulgare, mortality did not vary with rainfall (Klemow & Raynal 1985). These results suggest that a dense community of herbs could naturally develop within the quarry if more water could be made available to the plants, either by irrigation or by improving the water-holding capacity of the substrate.