Meta-analysis of the differential effects of habitat fragmentation and degradation on plant genetic diversity |
| |
Authors: | Alejandra V González Valeria Gómez-Silva María José Ramírez Francisco E Fontúrbel |
| |
Institution: | 1. Departamento de Ciencias Ecológicas, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Ñuñoa, 7800024 Santiago, Chile;2. Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Av. Universidad 330, Valparaíso, 2373223 Chile |
| |
Abstract: | Genetic diversity is a key factor for population survival and evolution. However, anthropogenic habitat disturbance can erode it, making populations more prone to extinction. Aiming to assess the global effects of habitat disturbance on plant genetic variation, we conducted a meta-analysis based on 92 case studies obtained from published literature. We compared the effects of habitat fragmentation and degradation on plant allelic richness and gene diversity (equivalent to expected heterozygosity) and tested whether such changes are sensitive to different life-forms, life spans, mating systems, and commonness. Anthropogenic disturbance had a negative effect on allelic richness, but not on gene diversity. Habitat fragmentation had a negative effect on genetic variation, whereas habitat degradation had no effect. When we examined the individual effects in fragmented habitats, allelic richness and gene diversity decreased, but this decrease was strongly dependent on certain plant traits. Specifically, common long-lived trees and self-incompatible species were more susceptible to allelic richness loss. Conversely, gene diversity decreased in common short-lived species (herbs) with self-compatible reproduction. In a wider geographical context, tropical plant communities were more sensitive to allelic richness loss, whereas temperate plant communities were more sensitive to gene diversity loss. Our synthesis showed complex responses to habitat disturbance among plant species. In many cases, the absence of effects could be the result of the time elapsed since the disturbance event or reproductive systems favoring self-pollination, but attention must be paid to those plant species that are more susceptible to losing genetic diversity, and appropriate conservation should be actions taken. |
| |
Keywords: | allelic richness geographic origin heterozygosity life-form life span molecular markers plant reproduction recruitment forma de vida heterocigosidad marcador molecular origen geográfico reclutamiento reproducción de plantas riqueza de alelos tiempo de vida 等位基因丰富度 杂合度 地理起源 寿命 生活型 分子标记 植物繁殖 招募 |
|
|