As pinyon–juniper (specifically, Pinus monophylla and Juniperus osteosperma) woodlands in the western United States increase in distribution and density, understory growth declines and the occurrence of crown fires increases, leaving mountainsides open to both soil erosion and invasion by exotic species. We examined if the loss in understory cover that occurred with increasing tree cover was re...

this study aimed to investigate the effect of animal grazing on soil seed bank characteristics in the northern slopes of alborz. for this purpose, soil seed bank characteristics were compared between grazed and ungrazed areas. therefore, four transects perpendicular to the sides of exclosure inside and outside of it were established. then soil samples were collected within 28 plots inside and 2...

To evaluate the efficacy of passive restoration on soil seed bank and vegetation recovery, we measured the species composition and density of the soil seed bank, as well as the species composition, density, coverage, and height of the extant vegetation in sites passively restored for 0, 4, 7, and 12 years (S0, S4, S7, and S12) in a degraded grassland in desert land. Compared with S0, three more...

The overall goal of this research is to compare the effects of woody and herbaceous vegetation on stream bank erosion. This chapter presents the third of three substudies that address the impact of vegetation on stream bank erosion. The goal of this study was to determine the erodibility of rooted stream bank soils and to evaluate the relative effects of vegetation type, root density, and freez...

Soil seed banks serve as reservoirs for future plant communities, and when diverse and abundant can buffer vegetation communities against environmental fluctuations. Sparse seed banks, however, may lead to future declines of already rare species. Seed banks in wetland communities are often robust and can persist over long time periods making wetlands model systems for studying the spatial and t...