Restoration of high altitude forests in an area affected by a wildfire: Polylepis australis Bitt. seedlings performance after soil inoculation

• Published in: Trees (Berlin, West) West), 2014-02, Vol.28 (1), p.173-182
• Main Authors: Soteras, Florencia, Renison, Daniel, Becerra, Alejandra G
• Format: Article
• Language: English
• Subjects: Agriculture; Altitude; Biomedical and Life Sciences; Colonization; Community composition; community structure; ecosystems; Forest degradation; Forest soils; Forestry; forests; grassland soils; Grasslands; Indigenous species; Life Sciences; Mountain ecosystems; mycorrhizal fungi; Original Paper; Plant Anatomy/Development; Plant Pathology; Plant Physiology; Plant Sciences; Reforestation; Rhizosphere; seedling growth; Seedlings; shoots; soil inoculation; Soil testing; spores; Survival; Vegetation; vesicular arbuscular mycorrhizae; Wildfires
• ISSN: 0931-1890; 1432-2285
• DOI: 10.1007/s00468-013-0940-7

KEY MESSAGE : Outplanted Polylepis australis seedling growth, survival and mycorrhizal response were not influenced by inoculation with soil from different vegetation types. Seedling inoculation would not be essential for reforestation practices. Polylepis forests are one of the most endangered high mountain ecosystems of South America and reforestation with native Polylepis species has been recommended. To determine whether native soil inoculation could help in reforestation success, a field trial was set up to evaluate the response of outplanted P. australis seedlings to the inoculation with soils from three vegetation types (a grassland, a mature forest and a degraded forest) and a sterile soil, used as control. We evaluated seedlings performance: growth and survival for 18 months, root/shoot ratio, phosphorous content and arbuscular mycorrhizal fungal (AMF) colonization. To interpret performance patterns we evaluated the colonization potential of the three inoculum soils and the changes of the AMF community composition of the seedlings rhizosphere in relation to inoculation treatment and season. Our main results showed no significant differences in seedlings survival and growth between treatments. The colonization potential of grassland and degraded forest soils was ~25 times greater than mature forest soil and specific spore density of some morphospecies varied with season. However, AMF spore community of seedlings rhizosphere became homogenized after outplanting and was similar between treatments after 12 months. Therefore, we conclude that soil inoculation is not essential for outplanted P. australis survival and increase in height, and thus all the tested soils could be used as inocula, including grassland soils which in practice are the easiest to collect.