1- Malayer University
Abstract: (10 Views)
Extended Abstract
Introduction and Objective: The soil seed bank plays a vital role in maintaining the ecological and genetic diversity of plant communities. Following ecosystem disturbances, it serves as a reservoir for vegetation reestablishment. Numerous environmental and anthropogenic factors influence the density, diversity, viability, quantity, and composition of the soil seed bank. Studying the soil seed bank enables comparisons with aboveground vegetation, offering valuable insights for plant community management. Livestock movement through forested areas induces physical, chemical, and biological alterations due to trampling. Among these, biological changes—particularly in seed germination and diversity—are significant. Grazing compacts the soil and reduces its water infiltration capacity, thereby impeding seed germination. A review of existing literature reveals limited research in Iran on soil seed banks along livestock traffic routes in forests. Most studies have focused on pastures and forests under grazing and enclosure treatments, post-fire disturbances, and the relationship between seed banks and surface vegetation, as well as land-use impacts. This study aims to assess the diversity and germination potential of soil seed banks along a permanent livestock movement corridor. The findings can inform ecological restoration strategies to enhance the self-recovery capacity of these disturbed routes in the Zagros forests.
Material and Methods: The research was conducted in the Zagros forests, within the Delfan district of Lorestan Province. A livestock traffic route exceeding four kilometers was identified through field surveys. Soil sampling followed a randomized controlled design. Along the route, 20 one-square-meter plots were established at 100-meter intervals, starting from a random point. From each plot, soil samples were collected at two depths: 0–5 cm and 5–10 cm. A parallel set of 20 plots was established in adjacent forest areas, located at least 100 meters from the route’s centerline, with identical sampling procedures. The greenhouse germination method was employed to evaluate the soil seed bank. Samples were cultivated in sterilized sand beds (10×40 cm), and germinated seedlings were counted, identified, and removed at 12-day intervals. After two weeks, trays underwent a drought treatment, followed by irrigation and further monitoring until germination ceased. Plant identification was conducted using the Flora of Iran. Seed density was calculated per unit area, and species diversity was assessed using Shannon-Wiener and Simpson indices. Statistical comparisons between the livestock route and forest plots were performed using unpaired t-tests.
Results: A total of 49 plant species from 17 families were identified, comprising one tree species, two shrubs, five annual herbs, and 41 perennials. Of these, eight species were exclusive to the forest, two to the livestock route, and 39 were common to both. Life-form analysis revealed hemicryptophytes as the dominant group in both areas—29.7% in the forest and 37.0% along the livestock route. Geophytes had the lowest representation: 4.0% in the forest and 2.5% on the route. Livestock movement increased hemicryptophyte prevalence while reducing other life forms. Unpaired t-tests indicated a statistically significant difference in seed density between the two depths (0–5 cm and 5–10 cm) and between the forest and livestock route at the 99% confidence level. Biodiversity indices also differed significantly: the Simpson index was higher in the forest (0.90) than on the route (0.82), and the Shannon-Wiener index followed a similar trend (0.86 vs. 0.79).
Conclusion: The study demonstrates that hemicryptophytes dominate both forest and livestock traffic areas. However, biodiversity indices and seed density are significantly lower along livestock routes, indicating ecological degradation. These findings underscore the need for targeted restoration efforts to rehabilitate disturbed forest corridors. Understanding soil seed bank dynamics in modified ecosystems is essential for effective management and ecological recovery planning.
Introduction and Objective: The soil seed bank plays a vital role in maintaining the ecological and genetic diversity of plant communities. Following ecosystem disturbances, it serves as a reservoir for vegetation reestablishment. Numerous environmental and anthropogenic factors influence the density, diversity, viability, quantity, and composition of the soil seed bank. Studying the soil seed bank enables comparisons with aboveground vegetation, offering valuable insights for plant community management. Livestock movement through forested areas induces physical, chemical, and biological alterations due to trampling. Among these, biological changes—particularly in seed germination and diversity—are significant. Grazing compacts the soil and reduces its water infiltration capacity, thereby impeding seed germination. A review of existing literature reveals limited research in Iran on soil seed banks along livestock traffic routes in forests. Most studies have focused on pastures and forests under grazing and enclosure treatments, post-fire disturbances, and the relationship between seed banks and surface vegetation, as well as land-use impacts. This study aims to assess the diversity and germination potential of soil seed banks along a permanent livestock movement corridor. The findings can inform ecological restoration strategies to enhance the self-recovery capacity of these disturbed routes in the Zagros forests.
Material and Methods: The research was conducted in the Zagros forests, within the Delfan district of Lorestan Province. A livestock traffic route exceeding four kilometers was identified through field surveys. Soil sampling followed a randomized controlled design. Along the route, 20 one-square-meter plots were established at 100-meter intervals, starting from a random point. From each plot, soil samples were collected at two depths: 0–5 cm and 5–10 cm. A parallel set of 20 plots was established in adjacent forest areas, located at least 100 meters from the route’s centerline, with identical sampling procedures. The greenhouse germination method was employed to evaluate the soil seed bank. Samples were cultivated in sterilized sand beds (10×40 cm), and germinated seedlings were counted, identified, and removed at 12-day intervals. After two weeks, trays underwent a drought treatment, followed by irrigation and further monitoring until germination ceased. Plant identification was conducted using the Flora of Iran. Seed density was calculated per unit area, and species diversity was assessed using Shannon-Wiener and Simpson indices. Statistical comparisons between the livestock route and forest plots were performed using unpaired t-tests.
Results: A total of 49 plant species from 17 families were identified, comprising one tree species, two shrubs, five annual herbs, and 41 perennials. Of these, eight species were exclusive to the forest, two to the livestock route, and 39 were common to both. Life-form analysis revealed hemicryptophytes as the dominant group in both areas—29.7% in the forest and 37.0% along the livestock route. Geophytes had the lowest representation: 4.0% in the forest and 2.5% on the route. Livestock movement increased hemicryptophyte prevalence while reducing other life forms. Unpaired t-tests indicated a statistically significant difference in seed density between the two depths (0–5 cm and 5–10 cm) and between the forest and livestock route at the 99% confidence level. Biodiversity indices also differed significantly: the Simpson index was higher in the forest (0.90) than on the route (0.82), and the Shannon-Wiener index followed a similar trend (0.86 vs. 0.79).
Conclusion: The study demonstrates that hemicryptophytes dominate both forest and livestock traffic areas. However, biodiversity indices and seed density are significantly lower along livestock routes, indicating ecological degradation. These findings underscore the need for targeted restoration efforts to rehabilitate disturbed forest corridors. Understanding soil seed bank dynamics in modified ecosystems is essential for effective management and ecological recovery planning.
Keywords: Ecological restoration, plant life forms, soil seed bank, Delfan, diversity and richness indexes.
Send email to the article author
| Rights and permissions | |
 |
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. |
