Seedling establishment ofCastanopsis cuspidata var.sieboldii andPersea thunbergii on lava and scoria of the 1962 eruption on Miyake-jima Island,the Izu Islands

Seedling establishment ofCastanopsis cuspidata var.sieboldii Nakai andPersea thunbergii Kosterm. (Machilus thunbergii Sieb. et Zucc.) in early succession was studied on the lava and the scoria of the 1962 eruption on Miyake-jima Island of the Izu Islands. While tall individuals (> 1 m) ofP. thunbergii were found on both the lava and the scoria, those ofC. cuspidata (> 1 m) were found only on the lava. The height growth rate ofC. cuspidata was very low on the scoria, and there was no individual ofC. cuspidata taller than 0.4 m on the scoria. The proportion of yellow leaved individuals was much higher (37.1%) inC. cuspidata than inP. thunbergii (4.0%) on the scoria, while it was similar between the two species on the lava.Persea thunbergii seemed to be able to establish on both the lava and the scoria, butC. cuspidata established only on the lava. The differences in growth rate and vigor between the two species on the lava and the scoria in early succession may influence later stages of succession.     

Primary succession of Hawaiian montane rain forest on a chronosequence of eight lava flows

Abstract. The primary-successional sere of a Hawaiian montane rain forest was inferred from an age sequence of eight closely located ‘a’ ā flows (clinker type lava); 8, 50, 140, ca. 300, ca. 400, ca. 1400, ca. 3000 and ca. 9000 yr, on a windward slope of Mauna Loa, Hawaii. All study sites (0.2 ha each) were at 1120 — 1250 m a.s.l. with 4000 mm mean annual rainfall. The 400-yr, 1400-yr, and 9000-yr flows had younger volcanic ash deposits, while the others were pure lava. Comparisons of tree size and foliar nutrients suggested that ash increased the availability of nitrogen, and subsequently standing biomass. An Unweighted Pair Group Cluster Analysis on the samples (flows) using quantitative vascular species composition revealed that clusters were correlated with age regardless of the substrate types (pure lava vs. ash), and an indirect ordination on the samples suggested that the sequence of sample scores along axis 1 was perfectly correlated with the age sequence. Although ash deposits increased biomass, they did not affect the sequence of the successional sere. Both pubescent and glabrous varieties of Metrosideros polymorpha (Myrtaceae) dominated upper canopy layers on all flows ≥ 50 yr and ≤ 1400 yr, but the pubescent variety was replaced by the glabrous on the flows ≥ 3000 yr. Lower layers were dominated initially by a matted fern, Dicranopteris linearis, up to 300 yr, and subsequently by tree ferns, Cibotium spp., to 9000 yr. The cover of Cibotium declined slightly after 3000 yr, while other native herb and shrub species increased. A ‘climax’ stage in the conventional sense was apparently not reached on the observed age gradient, because the sere changed continuously in biomass and species; this divergent successional phenomenon may be unique to Hawaii where the flora is naturally impoverished and disharmonic due to its geographic isolation in contrast to more diverse and harmonic floras in continents.     

Zonation of forest vegetation and soils of Mount Cameroon,West Africa

Mount Cameroon is an active volcano in a wet part of West Africa. The forest vegetation and associated soils on its southern slopes were studied in 1989, 1991 and 1995 in coupled 0.25 ha plots at altitudes of 180, 600, 1,100, 1,800 and 2,180 m. All lianas and trees >10 cm dbh were enumerated and their structural features quantified. The forests were of large stature throughout. The strangling Schefflera species made a substantial contribution to the very high basal areas at 1,800 m. The associated soils were dominated by andisols derived from volcanic ash that showed a distinct increase with altitude in soil organic matter and total N attributed to lower temperatures. Soil pH, exchangeable K⁺, Ca²⁺, Mg²⁺, effective cation-exchange capacity and percentage base saturation showed very marked increases explained by the influence of recent volcanic ashfalls. Available N and P showed less distinct trends with altitude. Although there is a large decrease in tree species richness with altitude, forest stand growth (as compared on a basal area basis) does not appear to be limited by soil fertility or temperature. The forest line (altitude treeline and extensive gaps below it) appear to be controlled by periodic volcanic activity, ashfalls and lava flows, which can destroy existing forest through soil burial and fire effects and inhibit regrowth on bare lava flows and deep deposits of volcanic ash.     

Primary succession of the warm-temperate broad-leaved forest on a volcanic island, Miyake-jima, Japan

The primary successional sere of a warm-temperate forest was inferred from an age sequence of four basaltic volcanic substrates (16-, 37- and 125-yr-old lava flows, and volcanic ejecta older than 800 years) at several altitudes (ranging from 30 to 550 m) on Miyake-jima Island. The DCA analysis of species composition indicated that the vegetation is patterned by substrate age and altitude. The vegetation successionally changed fromAlnus sieboldiana shrub, toMachilus thunbergii andPrunus speciosa forest, toCastanopsis sieboldii forest at all altitudes. The rate of succession seems to be slower at higher altitudes. The above-ground biomass was 20 kg/m² (160 m a.s.l.) and 12 kg/m² (300 m a.s.l.) on the 125-yr-old lava flow, and 54 kg/m² (100 m a.s.l.) and 16 kg/m² (350 m a.s.l.) on the old ejecta. However, the large difference of above-ground biomass between low versus high altitudes on the old ejecta might not only reflect climatic differences but also past human disturbances at the higher altitude. In spite of the colder climate of Miyake-jima the rate of above-ground biomass accumulation here was considerably faster than that of a Hawaiian montane tropical evergreen forest on the same basaltic lava substrate. We suggest that the faster above-ground biomass development is due to the facilitation effects of N-fixation byAlnus. The inorganic N soil concentration was extremely high on the 37- and 125-yr-old lava flows whereAlnus was dominant. The foliar N concentration inAlnus was 2% irrespective of substrate age. The deposition of N fromAlnus via litterfall would decrease the soil C/N ratio, which in turn facilitates net soil N mineralization and consequently provides an ample supply of inorganic N to plants. N limitation on vegetation development, which is prevalent during the early stage of succession on volcanic lava flows or similar substrates elsewhere, is thus alleviated.     

Canonical correspondence analysis of early volcanic succession on Mt Usu,Japan

Canonical correspondece analysis (CCA) was applied to explore revegetation patterns during early succession on Mt Usu. Vegetation was buried by deposits of ash and pumice from 1 to 3 m in depth from the 1977–78 eruptions. Three habitats were selected: tephra, tephra in gully and original surface. Plant density and plant cover data were analyzed separately. Environmental factors consisted of five quanticative variables (organic matter, elevation, distance from colonizing source, erosion and deposition of volcanic deposits) and three nominal variables (habitat types: tephra, tephra in gully and original surface). Canonical correspondence analysis showed that the original surface played a special role in vegetation development because the old topsoil supplied both nutrients and seed-bank species. The CCA also suggested that the environmental factors that influence plant density and cover differ. Distance from colonizing source affected plant density while erosion affected cover. Using CCA, factors could be distinguished that influenced seedling establishment from vegetation expansion and vegetation recovery dynamics could also be more clearly interpreted.     

Rapid coral colonization of a recent lava flow following a volcanic eruption,Banda Islands,Indonesia

Compared to the catastrophic impacts of various environmental disturbances and the subsequent recovery of scleractinian coral communities from these events, little is known about the early successional dynamics of coral communities following major volcanic eruptions. The 1988 volcanic eruption of Gunung Api, Banda Islands, Indonesia, provided a unique opportunity to study the rate at which a reef-building coral community develops on an andesitic lava flow. Coral colonization was studied at three locations varying in substrate characteristics. Five years after the eruption, the sheltered lava flow supported a diverse coral community (124 species) with high coral cover . Tabulate acroporids were a dominant component of the lava flow coral community, with some colonies measuring over 90 cm in diameter. Higher average coral diversity, coral abundance and cover were recorded on the andesitic lava flow than on an adjacent carbonate reef not covered by the lava, and on a substrate of unstable pyroclastic deposits located on the southwestern coast of the volcano. In some areas of high coral diversity and environmental stability, andesitic lava flows may create local hot-spots of coral diversity by providing a structurally complex, predator-free and stable substrate for the recruitment of coral species from the adjacent and regional species pools.     

五大连池火山熔岩台地草本层物种多样性及环境解释

五大连池火山熔岩台地是一种火山地貌, 研究熔岩台地草本物种分布及其环境解释, 对认识火山原生演替过程中植物群落空间格局形成及适应机制具有重要意义。本文以五大连池熔岩台地的草本物种为研究对象, 调查了苔藓、草本、灌丛、阔叶林和针阔混交林等不同植被类型中的草本层样方, 并测定样方中的土壤养分和水分等状况, 采用多样性指数、优势度指数、均匀度指数、物种丰富度评价草本层物种多样性, 通过典范对应分析方法研究了群落组成与土壤因子的关系。结果表明: (1)熔岩台地草本层物种丰富, 共56种, 占本研究调查区总物种数的82.35%, 草本样地的草本层物种多样性、优势度和均匀性高于其他植被类型。(2)熔岩台地土壤pH值对群落草本层物种丰富度和物种个体的空间分布均有较大影响。(3)土壤因子解释了群落分布的79.39%, 其中土壤pH值、速效磷、硝态氮、铵态氮所占的解释量比较大。(4)岩败酱(Patrinia rupestris)、万年蒿(Artemisia sacrorum)、硬质早熟禾(Poa sphondylodes)和中华苦荬菜(Ixeris chinensis)对环境要求较低, 能够适应熔岩台地土壤贫瘠恶劣的环境。熔岩台地不同植被类型表现出对环境资源的特定需求, 熔岩地貌导致了土壤pH值、养分、水分的差异, 并影响植物群落的分布。     

Large scale stoat control to protect mohua (

Vegetation succession on 4 recent (1852-1942) montane lava Rows on Mauna Loa, Hawaii, was remeasured 22 years after the first measurement in 1967. Colonisation patterns of vascular plant species were observed on a new lava flow (1984) which overwhelmed part of the earlier studied 1852 flow. An influx of adventive species, positively correlated with flow age, was noted at the remeasured sites; most were herbs and grasses that do not appear to interfere with the succession to Metrosideros- dominated forest. Some indigenous species important in older forest, e.g., Cibotium glaucum, had apparently colonised all four remeasured flows regardless of flow age. Densities and total basal area of Metrosideros polymorpha increased on all flows, but a closed-canopy forest had not yet developed. Vascular plant aggregations comprising a mixture of adventive and indigenous species were found on the 1984 flow associated with soil or logs of the overwhelmed forest. This phenomenon may allow rare individual Metrosideros trees to be in place on a new flow within 10 years of its formation. A closed-canopy, self-thinned Metrosideros forest can develop within 400 years but dieback of colonising Metrosideros individuals and/or invasion of adventive species capable of altering ecosystem processes can delay this process.     

Primary Colonization of Volcanic Rocks by Plants in Arid Baja California, Mexico

Abstract: In an arid region of Baja California Sur, Mexico, field observations, combined with chemical and physical analyses, mineral analysis and scanning electron microscopy of unweathered and weathered volcanic rocks, revealed the presence of rock-colonizing plants (most are tree-shaped cacti, possibly rock weathering), growing in volcanic rocks without benefit of soil. Many are at the seedling stage. At least four cactus species ( Pachycereus pringlei [S. Wats] Britt. and Ross, Stenocereus thurberi [Engelm.] Buxb. subsp. thurberi, Mamillaria fraileana [Britt. and Rose] Boed., Opuntia cholla F. A. C. Weber), and one tree (wild fig, Ficus palmeri [S. Wats]) were capable of cracking, growing in and colonizing cliffs and rocks formed from ancient lava flows and, consequently, forming soil for succession by other plant species. This study shows that plant colonization of volcanic rocks may assist soil formation, which eventually leads to accumulation of soil, water and nutrients in a desert terrestrial ecosystem that otherwise lacks these essential plant-growth variables.     

Comparative bacterial diversity in recent Hawaiian volcanic deposits of different ages

Volcanic activity creates new landforms that can change dramatically over time as a consequence of biotic succession. Nonetheless, volcanic deposits present severe constraints for microbial colonization and activity. We have characterized bacterial diversity on four recent deposits at Kilauea volcano, Hawaii (KVD). Much of the diversity was either closely related to uncultured organisms or distinct from any reported 16S rRNA gene sequences. Diversity indices suggested that diversity was highest in a moderately vegetated 210-year-old ash deposit (1790-KVD), and lowest for a 79-year-old lava flow (1921-KVD). Diversity for a 41-year-old tephra deposit (1959-KVD) and a 300-year-old rainforest (1700-KVD) reached intermediate values. The 1959-KVD and 1790-KVD communities were dominated by Acidobacteria, Alpha- and Gammaproteobacteria, Actinobacteria, Cyanobacteria, and many unclassified phylotypes. The 1921-KVD, an unvegetated low pH deposit, was dominated by unclassified phylotypes. In contrast, 1700-KVD was primarily populated by Alphaproteobacteria with very few unclassified phylotypes. Similar diversity indices and levels of trace gas flux were found for 1959-KVD and 1790-KVD; however, statistical analyses indicated significantly different communities. This study not only showed that microorganisms colonize recent volcanic deposits and are able to establish diverse communities, but also that their composition is governed by variations in local deposit parameters.     

Episodic Eruptions of Volcanic Ash Trigger a Reversible Cascade of Nuisance Species Outbreaks in Pristine Coral Habitats

Volcanically active islands abound in the tropical Pacific and harbor complex coral communities. Whereas lava streams and deep ash deposits are well-known to devastate coral communities through burial and smothering, little is known about the effect of moderate amounts of small particulate ash deposits on reef communities. Volcanic ash contains a diversity of chemical compounds that can induce nutrient enrichments triggering changes in benthic composition. Two independently collected data sets on the marine benthos of the pristine and remote reefs around Pagan Island, Northern Mariana Islands, reveal a sudden critical transition to cyanobacteria-dominated communities in 2009–2010, which coincides with a period of continuous volcanic ash eruptions. Concurrently, localized outbreaks of the coral-killing cyanobacteriosponge Terpios hoshinota displayed a remarkable symbiosis with filamentous cyanobacteria, which supported the rapid overgrowth of massive coral colonies and allowed the sponge to colonize substrate types from which it has not been documented before. The chemical composition of tephra from Pagan indicates that the outbreak of nuisance species on its reefs might represent an early succession stage of iron enrichment (a.k.a. “black reefs”) similar to that caused by anthropogenic debris like ship wrecks or natural events like particulate deposition from wildfire smoke plumes or desert dust storms. Once Pagan''s volcanic activity ceased in 2011, the cyanobacterial bloom disappeared. Another group of well-known nuisance algae in the tropical Pacific, the pelagophytes, did not reach bloom densities during this period of ash eruptions but new species records for the Northern Mariana Islands were documented. These field observations indicate that the study of population dynamics of pristine coral communities can advance our understanding of the resilience of tropical reef systems to natural and anthropogenic disturbances.     

Deccan volcanism,the KT mass extinction and dinosaurs

Recent advances in Deccan volcanic studies indicate three volcanic phases with the phase-1 at 67.5 Ma followed by a 2 m.y. period of quiescence. Phase-2 marks the main Deccan volcanic eruptions in Chron 29r near the end of the Maastrichtian and accounts for ∼80% of the entire 3500 m thick Deccan lava pile. At least four of the world’s longest lava flows spanning 1000 km across India and out into the Gulf of Bengal mark phase-2. The final phase-3 was smaller, coincided with the early Danian Chron 29n and also witnessed several of the longest lava flows. The KT boundary and mass extinction was first discovered based on planktic foraminifera from shallow marine intertrappean sediments exposed in Rajahmundry quarries between the longest lava flows of the main volcanic phase-2 and smaller phase-3. At this locality early Danian (zone P1a) planktic foraminiferal assemblages directly overlie the top of phase-2 eruptions and indicate that the masse extinction coincided with the end of this volcanic phase. Planktic foraminiferal assemblages also mark the KT boundary in intertrappean sediments at Jhilmili, Chhindwara, where freshwater to estuarine conditions prevailed during the early Danian and indicate the presence of a marine seaway across India at KT time.     

Species turnover and diversity during early stages of vegetation recovery on the volcano Usu,northern Japan

To study the rate of revegetation during succession on the volcano Usu, northern Japan, vegetation structure and species composition were monitored from 1984 to 1988 in permanent quadrats near the summit of the volcano, which had been almost completely deforested by 1 to 3 m thick volcanic deposits in 1977–78. Analyses of vegetation structure included species richness, species diversity (IT), evenness (J'); year-to-year changes were quantified using Community Coefficient (CC), and Percentage Similarity (PS). While species turnover rates fluctuated and vegetation cover gradually increased, species richness, diversity and evenness did not fluctuate much. The diversity parameters showed slightly different levels for three habitat types distinguished. CC values comparing subsequent years with the starting year 1984 suggest only minor changes in qualitative species composition; PS values decreased more rapidly, indicating larger changes in species cover. A few well-rooted perennial plants were predominant, therefore, PS decline resulted from dominance-controlled community structure. PS-value detected not only habitat difference, but also the rate of the volcanic succession, suggesting that PS is most effective to evaluate successional pace.     

五大连池新期火山熔岩台地不同植被类型土壤微生物群落的功能多样性

土壤微生物群落是陆地生态系统的重要生物活性成分,其结构和功能多样性直接影响到系统的碳、氮等生态过程,微生物群落功能多样性与地上植被类型变化密切相关,开展植被类型对土壤微生物群落功能多样性的影响研究具有重要意义。以五大连池新期火山熔岩台地苔藓、草本、灌丛、矮曲林、针阔混交林5种典型植被类型为对象,利用BIOLOG微孔板法研究不同演替阶段植被类型土壤微生物群落功能多样性特征。结果表明：不同植被类型土壤微生物群落功能多样性存在显著差异。平均颜色变化率（AWCD）随培养时间延长而逐渐增加,大小顺序为：苔藓 > 针阔混交林 > 矮曲林 > 草本 > 灌丛。灌丛土壤微生物多样性指数与其他植被类型间差异显著。主成分分析结果表明,主成分1和主成分2分别能解释变量方差的56.24%和29.59%,不同植被类型下土壤微生物的碳源利用格局差异主要是由氨基酸类和带磷基糖类引起,二者合计解释总变异量的47.51%。冗余分析表明,速效磷、铵态氮、C：N和pH对微生物功能多样性具有显著的影响,羧酸类、氨基酸类、酯类和胺类的降解更易受到环境因素的影响。研究结果为进一步探讨植被类型与土壤微生物之间在植被演替过程中的关系提供参考。     

Bacterial Diversity of Terrestrial Crystalline Volcanic Rocks, Iceland

Bacteria inhabiting crystalline rocks from two terrestrial Icelandic volcanic lava flows of similar age and from the same geographical region, but differing in porosity and mineralogy, were characterised. Microarray (PhyloChip) and clone library analysis of 16S rRNA genes revealed the presence of a diverse assemblage of bacteria in each lava flow. Both methods suggested a more diverse community at the Dómadalshraun site (rhyolitic/andesitic lava flow) than that present at the Hnausahraun site (basaltic lava flow). Proteobacteria dominated the clone library at the Dómadalshraun site, while Acidobacteria was the most abundant phylum in the Hnausahraun site. Although analysis of similarities of denaturing gradient gel electrophoresis profiles suggested a strong correlation of community structure with mineralogy, rock porosity may also play an important role in shaping the bacterial community in crystalline volcanic rocks. Clone sequences were most similar to uncultured microorganisms, mainly from soil environments. Of these, Antarctic soils and temperate rhizosphere soils were prominent, as were clones retrieved from Hawaiian and Andean volcanic soils. The novel diversity of these Icelandic microbial communities was supported by the finding that up to 46% of clones displayed <85% sequence identities to sequences currently deposited in the RDP database.     

Successional pattern above timberline in south-central Chile

Summary In the above-timberline zone of south-central Chile, stepped microtopography commonly develops on slopes of unstable volcanic ash deposits. Between the Nothofagus timberline and the high-altitude sparse fellfields, a scrubgrassland vegetation dominated by prostrate shrubs such as Empetrum rubrum and Pernettya spp. and tussock grasses such as Hierochloe utriculata and Cortaderia pilosa characteristically occurs on the stepped microtopography. Species interactions and species-microtopography interactions during the course of succession on the recent volcanic deposits were investigated by means of pattern analysis. Scales of pattern associated with individual plant morphology and interspecific interactions are present but, in general, the scales of pattern attributed to environmental variation are more evident. Cyclic changes occur in the scrub-grassland under the influence of periodic burial by the unstable ash substrate and the life cycles of the dominant prostrate shrubs. Such cyclic changes are part of a long-term linear successional trend following disturbance by catastrophic vulcanism. In contrast to the basic assumption of classic successional theory, in both the short-term and long-term the physical habitat in the above-timberline zone of south-central Chile is fundamentally unstable.Except where nomenclatural authorities are indicated, nomenclauture follows Muñoz (1966).Part of this work was supported by the Dirección de Investigación of the Universidad Austral de Chile under Project S-78-12. We thank A. Veblen for assisting with various aspects of this study.Sponsored by the Smithsonian-Peace Corps Environmental Program.     

Primary faunal succession in volcanic terrain: lava and cave studies on the Canary Islands

Invertebrate communities in volcanic habitats of different ages on the islands of La Palma and El Hierro were studied using standardized trapping and searching techniques. A variety of graphical and numerical approaches were used to analyse relationships among the sites. Young, barren lava flows constitute aeolian ecosystems with a fauna of generalized detritivores and predators, especially collembolans, earwigs, thysamirans and crickets. Surface samples have many individuals and low diversity; those from caves have smaller numbers but similar taxonomic composition.
Vegetated surface habitats have richer communities, with diverse herbivores and predators but largely without the pioneer 'lavicolous' species. Caves with high humidity and stable temperature contain mainly specialized troglobitic species, but if there are both dry and humid sections lavicoles may also be present. Divergence into distinct epigean and hypogean communities results from both abiotic and biotic processes, including erosion and plant succession. While these occur mainly on the surface they also affect caves, increasing humidity and providing insulation from variations in external environmental conditions; the process is considered as a form of 'maturation' of the caves. Various models of succession are considered, which might help to account for the disappearance of lavicoles from mature epigean and hypogean communities.     

Quaternary carbonate-rocky talus slope successions (Eastern Alps, Austria): sedimentary facies and facies architecture

Quaternary carbonate-lithic talus slope successions of the Eastern Alps record an overall correlation between prevalent sedimentary facies, depositional geometry, and geomorphic maturity of the slope. After exposure of high cliffs by deglaciation or rocksliding, a low-dipping immature talus dominated by unsorted rockfalls initially accumulates. With progressive talus buildup, slope segments of different dips develop. Concomitantly, prevalent depositional processes change to grain flows and sorted rockfalls in the proximal, steep-dipping (35°–30°) slope segment, while deposits of cohesive debris-flows, ephemeral fluid flows and larger rockfalls prevail in the distal, lower-dipping slope segment. In mature talus deposystems, the proximal slope succession overlies the lower-dipping package of the distal slope along a thin ‘downlap interval’. Immediately after cliff exposure by deglaciation or rocksliding, talus may aggrade at rates of up to a few tens of meters per 1,000 years, but the accumulation rate slows strongly with progressive maturity of slopes. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Long-term primary succession: a comparison of non-spatial and spatially explicit inferential techniques

Trajectories of plant primary succession are commonly inferred from temporal changes in non-spatially explicit metrics that characterise the whole sampling area with a single statistic (e.g. community diversity). However, the derivation of these metrics is affected by the presence of spatial structure (patchiness) in vegetation. The emergence of spatial patchiness during succession is therefore likely to have an impact on attempts to infer the rate and direction of vegetation development. This study examines the impact of patchiness on inferred developmental trajectories by comparing a non-spatial analysis of long-term primary succession with a spatially explicit analysis of the same data. The data used in the analysis were collected from an 850-year-old chronosequence of 7 lava flows in southern Iceland. The non-spatial analysis captured broad developmental trends, including an overall increase in community diversity with time, and a split between early pioneer communities (sites <150-year-old) dominated by cryptogams and later assemblages (sites older than ≈150 years) where vascular plants were more important. However, the non-spatial analysis missed key community processes apparent in the spatially explicit analysis, including divergence in vegetation development related to metre-scale topographic differences. The results of this study emphasise the need for spatially explicit, multi-scale studies of vegetation development, both in the inference of past vegetation dynamics, and in modelling the response of spatially patchy vegetation to future environmental change.     

Biological legacies promote succession and soil development on tephra from the Puyehue‐Cordon Caulle eruption (2011)

Volcanic deposits have frequently been studied from a successional point of view, but the main focus has been on vegetation dynamics, and less frequently on the development of invertebrate and microbial communities and soil properties. Biological legacies, understood as living organisms, seeds, organic debris and biologically derived patterns in soils and understories, are important in succession, and may also influence soil development on young volcanic deposits. The volcanic eruption of the Chilean Puyehue–Cordón Caulle complex (Northern Patagonia) in June 2011 deposited tephra in southern Argentina. Sandy tephra up to 30 cm deep was deposited in the De los Siete Lagos road in Nahuel Huapi and Lanín National Parks, where a road under construction had exposed sub‐soil lacking vegetation, while adjacent forest supported a canopy of Nothofagus dombeyi with Chusquea culeou in the understory. This situation provided a unique opportunity to study soil development and succession on nearby young volcanic deposits with different biological legacies, considering several biological communities. Our hypothesis is that 29 months after the eruption the tephra in the forest would have higher organic C, total N, available P and biological activity than the tephra deposited on the roadside. Plant cover and species richness, invertebrate abundance and richness, as well as substrate respiration, N mineralization and enzymatic activities were highest in the forest. In addition, organic carbon and nutrient incorporation rates in the forest were twice those in the roadside substrate. Nevertheless, two and a half years after the eruption, most variables remained an order of magnitude lower than values expected for temperate forest soils. Surviving canopy and understory play a key role in ecosystem recovery after tephra deposition, providing seeds and organic matter and establishing conditions appropriate for plants, invertebrates, and microorganisms that would in turn accelerate soil development.