Category: Ecological Research
Title: Soil Seed Banks in a Mature Coniferous Forest Landscape: Dominance of Native Perennials and Low Spatial Variability
Author: * Springer, J.D.
Subject: Seed bank, Native Perennials, Conifer Forest
Abstract: Viable seeds stored in soil (soil seed banks) are important features of plant communities that contribute to site potential for restoration and recovery from disturbance (events that disrupt an ecosystem such as fire or logging). Seed banks typically contain few seeds of late-successional species. Rather, forest seed banks are normally dominated by early successional species, often short-lived (e.g., annual) and “ruderal” (weedy) species with abilities to rapidly colonize disturbed areas. When disturbance reduces the tree overstory, these species recruit, produce seed to replenish seed banks, and then often become sparse or absent aboveground as forest canopy increases. On the other hand, above-ground species of a late-successional forest often do not rely on soil seed banks. Instead, these species are usually long-lived, rendering persistent seed banks of minimal importance to their population dynamics. As a result, seed banks of late-successional forests are generally dominated by species other than those of the existing mature vegetation. Soil seed bank samples were collected on the east side of the Spring Mountains in southern Nevada (Figure 1, page 2). We used a network of Terrestrial Ecological Unit Inventory (TEUI) sites established by the U.S. Forest Service to characterize variability in environmental gradients and vegetation across the landscape. These sites were established in the centers of mapping units defined on the basis of similarity in climate, soil parent material and vegetation. With much of the study area roadless and in designated wilderness, human disturbance at the sites over the past 50–100 years is not extensive. Sample sites encompassed broad environmental and vegetation gradients across the landscape, ranging in elevation from 7,039 feet to 10,798 feet in forest types that included pinyon–juniper, pinyon pine, pondero-sa pine, mixed conifer and bristlecone pine.
Type: Fact Sheet
Source: ERI - Fact Sheet
Publisher: Ecological Research Institute