Using forest growth trajectory modelling to complement BioCondition assessment of mine vegetation rehabilitation

The standard rehabilitation objective for open‐cut mines in Queensland is to establish a self‐sustaining native forest ecosystem. Consequently, mine regulators and managers need tools to project whether sites are likely or not to meet agreed completion criteria and to ensure timely remedial interventions. The Ecosystem Dynamics Simulator (EDS) is such a tool capable of modelling forest dynamics and projecting long‐term growth of woody species only. Here, the model was applied to rehabilitation sites aged between 5 and 22 years in Meandu open‐cut coal mine in southeast Queensland. EDS projected structural characteristics for trees (height, diameter, basal area, foliage projective cover and stem density) and tree species composition as a function of rehabilitation age. Projected stand growth attributes were assessed against BioCondition benchmarks developed from eucalypt (Eucalyptus/Corymbia) remnant forests adjacent to the mine. Growth trajectories indicated that sites with >30% eucalypt basal area composition were more likely to develop into eucalypt‐dominated self‐sustaining ecosystems compared with sites that were initially dominated by acacias (Acacia spp.). Projections suggested that some benchmark attributes such as number of large eucalypt trees would take more than 70 years to be met. The application of EDS provided a framework to support decisions on early remedial intervention and assess the risk associated with lease relinquishment.     

Two‐tiered methodology for the assessment and projection of mine vegetation rehabilitation against mine closure restoration goal

Reinstatement of a ‘self‐sustaining native ecosystem’ is an increasingly common revegetation goal for open‐cut mines in Australia. This is usually applied as a regulatory requirement for mine closure, with some mines aiming for a high standard of ‘ecological restoration’. There is a growing appreciation that ecological restoration outcomes of mine rehabilitation are unachievable within the life of a mine and that assessment methodologies are subjective and inadequate to provide the high degree of confidence needed for mine closure. Here we elaborate on the integration of the BioCondition assessment and the Ecosystem Dynamics Simulator (EDS) trajectory methodologies. We also demonstrate an alternative early relinquishment assessment criteria similar to that used for early recruitment of regrowth native vegetation that exhibit structural characteristics of undisturbed native vegetation into remnant status in Queensland. We used ten age cohorts of rehabilitation ranging from three to 22 years at Meandu coal mine, south‐east Queensland. All the sites gained average BioCondition scores ranging from 19 to 44 out of possible score of 65. Growth trajectories indicated decline in species and basal area on all sites in the next three decades as the dense stock of short‐lived acacia species senesce and die. None of the sites are projected to meet self‐sustaining status by 2072, but there is evidence in some of a progression. All the sites except two (K2.3 and SW2) are projected to achieve remnant vegetation status by 2062. Applying the remnant vegetation criteria results in shorter timeframes and robustly evaluates whether sites are progressing towards the self‐sustaining ecosystem mine closure goal.     

Woody plants' diversity,structural analysis and regeneration status of Wof Washa natural forest,North‐east Ethiopia

Wof‐Washa forest is one of the few remaining dry Afromontane forests in the central plateau of Ethiopia. Woody species composition, structure and regeneration patterns of this forest were studied to generate information essential for formulating feasible management options for the forest. Vegetation data were collected from 64 quadrats of size 20 m × 20 m, 10 m × 10 m and 5 m × 5 m for tree/shrub, sapling and seedling, respectively, laid systematically along transects. A total of 62 woody species belonging to 54 genera and 40 families were recorded. Rosaceae was the most diverse family with five (12.5%) species followed by Anacardiaceae, Euphorbiaceae and Myrsinaceae with three (7.5%) species each. Tree/shrub, sapling and seedling densities were 699, 1178 and 7618.7 individuals/ha. About 56.7% of the importance value index was contributed by Juniperus procera, Maytenus arbutifolia, Podocarpus falcatus and Ilex mitis. Vegetation classification resulted in five plant communities: Ilex mitis – Maytenus obscura, Galiniera saxifraga – Maesa lanceolata, Juniperus procera – Erica arborea, Podocapus falcatus – Allophylus abyssinicus and Pittosporum viridiflorum – Polycias fulva community types. Regeneration status of all the woody plant species was categorized as ‘Good’ (28%), ‘Fair’ (19%), ‘Poor’ (8%), ‘None’ (40%) and ‘New’ (5%).     

Assessing the assessors: Quantifying observer variation in vegetation and habitat assessment

Vegetation assessment protocols used in research, monitoring and statutory planning often rely on the consistent application of methods by multiple assessors. Consequently, a study was undertaken to evaluate the application of a vegetation condition assessment protocol by a range of assessors. The aim of the study was to quantify variation among assessors in their measurement of field‐based vegetation attributes using Queensland’s BioCondition protocol, and to determine the effect of variability on the final condition score. The study consisted of 77 assessors, ranging from nil to 25 years experience in vegetation assessment, who each undertook an assessment at one site following training. Six of the 20 attributes used to derive the final condition score were not assessed consistently, this being because of a small number of assessors who had misinterpreted the protocol and had inappropriately assessed some attributes. Despite inclusion of outliers, 82% of assessors were within 10 points of the median condition score for the site. Based on the results, the definition and measurement of problematic attributes have been either clarified or removed from the revised assessment procedure. The study demonstrated that with training prior to use, assessors were able to consistently assess condition at the study site.     

Net woody vegetation increase confined to seasonally inundated lowlands in an Australian tropical savanna,Victoria River District,Northern Territory

Abstract Georeferenced digital aerial photographs were used to assess changes in overstorey vegetation cover since 1948 in the Victoria River District, Northern Territory, Australia, across a range of lowland tropical savanna habitats and with explicit consideration of known and variable site‐specific grazing and fire management histories. Vegetation surveys at corresponding locations on the ground identified five distinct woody vegetation communities defined primarily by water drainage and secondarily by soil characteristics. Air‐photo analyses revealed that, contrary to popular perceptions and in contrast to results from other habitats, there has been no generalized net increase in overstorey woody vegetation cover across the full range of lowland savanna habitats. Rather, different habitats exhibited distinctly different vegetation change mechanisms: low‐lying seasonally inundated ‘wet’ habitats have experienced woody vegetation increase since 1948, whereas well‐drained ‘dry’ habitats have experienced overstorey vegetation stability or loss. In almost every instance woody vegetation increase could be attributed to the invasion or proliferation of a single species, Melaleuca minutifolia F.Muell. The extent of M. minutifolia increase was unrelated to historical grazing/fire regime. Demographic analyses for this species revealed that recruitment was often episodic and that synchronized recruitment events occurred uniformly across the full range of historical management treatments, most likely as a consequence of favourable climatic conditions in years with an extended wet season. Heavy grazing facilitated juvenile survival and/or recruitment, most likely by reducing grassy fuel loads and eliminating landscape fire. We conclude that while there has been no generalized net increase in overstorey woody vegetation cover in lowland environments, savanna dynamics are complex, and multiple change mechanisms have occurred simultaneously in different habitats, some of which have been significantly transformed since 1948. Where net woody vegetation increase has occurred it is primarily a natural consequence of episodic M. minutifolia establishment in climatically favourable years, but the extent and magnitude of this effect is likely mediated by fire/grazing regime.     

Influence of woody vegetation on pollinator densities in oilseed Brassica fields in an Australian temperate landscape

Wild pollinators may benefit Brassica oilseed production in temperate Australia, yet it is not known how the density of potential pollinators varies in these landscapes. In this study we assessed whether the density of feral honeybees, hoverflies (probably 2 species) and native bees (multiple species) in temperate Australian Brassica oilseed crops was related to the composition of the landscape. The density of pollinators was measured at multiple points in six different Brassica oilseed paddocks (20–80 ha) at least 1.75 km apart. Landscape composition at multiple scales (radii 100–2000 m) was determined from GIS layers of Brassica paddocks, woody vegetation and non-woody vegetation, and a derived layer expected to reflect the condition of woody vegetation remnants (the ‘Link’ score). Densities of feral honeybees were higher near the edges of Brassica fields than towards the middle. Densities of feral honeybees were strongly positively associated with the summed ‘Link’ score within 300 m and with the amount of woody vegetation. Densities of native bees and hoverflies were not strongly associated with woody vegetation or with woody vegetation with a high ‘Link’ score. Our results suggest that maximising feral honeybee abundance within paddocks in these landscapes may require smaller paddocks than those typically used, interspersed with habitat beneficial to feral honeybees such as woody vegetation in good condition.     

Vegetation structure and ground cover attributes describe the occurrence of a newly discovered carnivorous marsupial on the Tweed Shield Volcano caldera,the endangered black‐tailed dusky antechinus (Antechinus arktos)

The black‐tailed dusky antechinus (Antechinus arktos) is a recently discovered, endangered, carnivorous marsupial mammal endemic to the Tweed Shield Volcano caldera, straddling the border between Queensland and New South Wales in eastern Australia. The species' preference for cool, high‐altitude habitats makes it particularly vulnerable to a shifting climate as these habitats recede. Aside from basic breeding and dietary patterns, the species' ecology is largely unknown. Understanding fine‐scale habitat attributes preferred by this endangered mammal is critical to employ successful conservation management. Here, we assess vegetation attributes of known habitats over three sites at Springbrook and Border Ranges National Parks, including detailed structure data and broad floristic assessment. Floristic compositional assessment of the high‐altitude cloud rainforest indicated broad similarities. However, only 22% of plant species were shared between all sites indicating a high level of local endemism. This suggests a diverse assemblage of vegetation across A. arktos habitats. Habitat characteristics were related to capture records of A. arktos to determine potential fine‐scale structural habitat requirements. Percentage of rock cover and leaf litter were the strongest predictors of A. arktos captures across survey sites, suggesting a need for foraging substrate and cover. Habitat characteristics described here will inform predictive species distribution models of this federally endangered species and are applicable to other mammal conservation programs.     

Habitat preferences of small mammals in tropical open-forest of the Northern Territory

Pattern analysis was used to investigate the habitat preferences of five small mammal species in tropical open-forest of the Northern Territory. Fifty-one sites were classified by faunal abundance and the groups examined for significant differences in vegetation structural attributes and plant species in both dry and wet seasons. The omnivore Isoodon macrourus showed strong association with floristic and vegetation structural attributes only in the dry season, when areas with a dense understorey of small trees and shrubs and a high percentage of leaf litter cover were favoured. Of the two primarily carnivorous species, Antechinus bellus was related strongly with floristic and structural attributes in both seasons and showed a consistent preference for areas with relatively dense low-level foliage (< 2m). By contrast, Dasyurus hallucatus was associated more with the structurally simple open-forest types. Of the two mainly herbivorous species Mesembdomys gouldii showed associations only withfioristics in both seasons, while the habitat relationships of Trichosurus arnhemensis were very weak due to its low abundance in the study area. The number and strength of animal/habitat relationships were greatest in the dry season. Forest types with dense mid-level foliage and abundant hollow logs and leaf litter had the greatest mammal richness and abundance; these areas may be critical to the survival of local mammal populations. A comparison of site-groups, defined independently on the basis of fauna, floristics or structure, showed that animal groups overlapped one to six of the habitat groups. The animal's perception of s‘habitat’ may thus differ from that of humans, or that defined by measurement of habitat attributes.     

Spatial model for predicting the presence of cinnamon fungus (Phytophthora cinnamomi) in sclerophyll vegetation communities in south‐eastern Australia

Abstract The pathogen Phytophthora cinnamomi causes extensive ‘dieback’ of Australian native vegetation. This study investigated the distribution of infection in an area of significant sclerophyll vegetation in Australia. It aimed to determine the relationship of infection to site variables and to develop a predictive model of infection. Site variables recorded at 50 study sites included aspect, slope, altitude, proximity to road and road characteristics, soil profile characteristics and vegetation attributes. Soil and plant tissues were assayed for the presence of the pathogen. A geographical information systyem (GIS) was employed to provide accurate estimations of spatial variables and develop a predictive model for the distribution of P. cinnamomi. The pathogen was isolated from 76% of the study sites. Of the 17 site variables initially investigated during the study a logistic regression model identified only two, elevation and sun‐index, as significant in determining the probability of infection. The presence of P. cinnamomi infection was negatively associated with elevation and positively associated with sun‐index. The model predicted that up to 74% of the study area (11 875 ha) had a high probability of being affected by P. cinnamomi. However, the present areas of infection were small, providing an opportunity for management to minimize spread into highly susceptible uninvaded areas.     

Why do some species have geographically varying responses to fire history?

A capacity to predict the effects of fire on biota is critical for conservation in fire‐prone regions as it assists managers to anticipate the outcomes of different approaches to fire management. The task is complicated because species’ responses to fire can vary geographically. This poses challenges, both for conceptual understanding of post‐fire succession and fire management. We examine two hypotheses for why species may display geographically varying responses to fire. 1) Species’ post‐fire responses are driven by vegetation structure, but vegetation – fire relationships vary spatially (the ‘dynamic vegetation’ hypothesis). 2) Regional variation in ecological conditions leads species to select different post‐fire ages as habitat (the ‘dynamic habitat’ hypothesis). Our case study uses data on lizards at 280 sites in a ～ 100 000 km² region of south‐eastern Australia. We compared the predictive capacity of models based on 1) habitat associations, with models based on 2) fire history and vegetation type, and 3) fire history alone, for four species of lizards. Habitat association models generally out‐performed fire history models in terms of predictive capacity. For two species, habitat association models provided good discrimination capacity even though the species showed geographically varying post‐fire responses. Our results support the dynamic vegetation hypothesis, that spatial variation in relationships between fire and vegetation structure results in regional variation in fauna–fire relationships. These observations explain how the widely recognised ‘habitat accommodation’ model of animal succession can be conceptually accurate yet predictively weak.     

First record of mating behaviour and induced parturition of the Brazilian endemic Lutz's stingray Hypanus berthalutzae

The recently described Lutz's stingray Hypanus berthalutzae is endemic to the Brazilian Province, including oceanic islands. Although it is expected to have life-history traits similar to the southern stingray H. americanus, little is known about its reproductive biology. Here we present the first observations of courtship behaviour (n = 4), copulation (n = 3) and an induced parturition of H. berthalutzae at the Fernando de Noronha Archipelago, an insular Marine Protected Area from the Equatorial Atlantic Ocean. The mating event records included (1) ‘chasing/close following’, (2) ‘biting/precopulatory biting’, (3) ‘insertion/copulation’ and (4) ‘separation’. These results are especially relevant considering that records of reproductive behaviour in the wild are rare for elasmobranchs in general. Mating events occurred in different months, suggesting that the reproductive cycle of H. berthalutzae in this insular system is asynchronous, as observed for other stingray species in regions with favourable environmental conditions and abundant food throughout the year. The opportunistic documentation of the induced parturition allowed for direct nonlethal observation of the two pups at or near full term in late May. Although preliminary, these observations should be considered in future management plans as they provide relevant data about the life-history traits and mating behaviour of this endemic and threatened species.     

The urban matrix and artificial light restricts the nightly ranging behaviour of Gould's long‐eared bat (Nyctophilus gouldi)

Cities are heterogeneous landscapes, with remnant vegetation interspersed amongst areas designed for human use. Native wildlife remaining in urban areas are only likely to thrive and persist if they incorporate human altered areas into what they perceive as habitat. Many sensitive species may be lost if they are restricted to remnant vegetation, and cannot use the urban matrix. In this study, we quantify spatial aspects of the ranging behaviour of Gould's long‐eared bat (Nyctophilus gouldi) using radio‐telemetry and acoustic surveys to determine use of the suburban–bushland interface. This species represents a group prone to extinction due to biological attributes that adapt it to flight within cluttered vegetation, making it more specialized. We radio‐tracked 19 individuals in Cumberland State Forest (CSF), a 40‐ha remnant located in north‐west Sydney, New South Wales, Australia. The nightly range (95% Kernel Density Estimator) was small and localized, and was no greater than 80 ha, where individuals moved on average less than 300 m from roosts each night. All individual N. gouldi tracked used bushland in an almost obligate manner, where up to 100% of used habitat was within local bushland, with little to no use of areas classified as ‘urban’ (residential, commercial and educational land uses). Small open spaces exposed to artificial lighting within the main ranging area of CSF had significantly lower activity (bat passes) of Nyctophilus spp. and significantly higher activity of other species more tolerant of urbanization (P < 0.05). Our results demonstrate that artificial lighting can ‘spill‐over’ into bushland and alter the use of preferred habitat. We conclude that large patches (>40 ha) of protected remnant vegetation must be managed to reduce further degradation, and smaller isolated patches could be restored to provide habitat, particularly in narrow bushland corridors, to assist these species to tolerate urban areas.     

Factors Controlling Compositional Changes in a Northern Andean Páramo (La Rusia,Colombia)

In this study, we aimed to assess the processes controlling compositional change in a Northern Andean páramo highly affected by human‐induced disturbances over the last few decades (La Rusia, Colombia). Along the 3000–3800 m asl altitudinal range, we randomly sampled fifty 10 × 10 m plots. Therein, we measured altitude and variables related to soil conditions (i.e., moisture, nutrient contents, bulk density, and texture), occurrence of human‐induced disturbances (i.e., fire, vegetation clearing, potato cultivation, and cattle grazing), and land‐use history. We also recorded richness and abundance of plant species, identifying them as exotic or native. We differentiated four groups of plots according to their species composition. The groups had significant differences in altitude, soil conditions, land‐use history, and particularly, in richness of exotic species and exotic/native cover ratio. They could be ascribed to shrub‐ and grass‐páramo vegetation types based on their relative dominance of woody and herbaceous species; however, these groups were not arranged according to the hypothetical composition of altitudinal belts, but rather formed a mosaic of patches. This mosaic was determined not only by altitude but also by soil conditions and disturbance history of sites. Our results corroborate recent findings which highlight shrub‐ and grass‐páramo vegetation types as patches of contrasting species composition and structure that depend on local environmental variables, as well as human‐induced disturbances as a major determinant of compositional discontinuities in these ‘high mountain’ tropical ecosystems.     

Dietary variation of an endangered mycophagous mammal in novel and remnant habitats in a peri-urban landscape

Understanding how fundamental aspects of species’ ecology, such as diet, are affected in human-dominated landscapes is vital for informing management and conserving biodiversity – particularly where species influence important ecosystem functions. Digging, mycophagous (‘fungus-eating’) mammals play various such roles, including the dispersal of hypogeal (‘truffle-like’) fungi. The endangered, mycophagous southern brown bandicoot (Isoodon obesulus obesulus: Peramelidae) persists in a peri-urban landscape south-east of Melbourne, Australia, where it occupies both ‘novel’ habitats (linear strips of vegetation along roadsides, drains and railway lines) and ‘remnant’ habitats (larger blocks of native vegetation) within dedicated conservation areas. It remains unknown how bandicoot diet, including the diversity of hypogeal fungi, varies between these habitat types, yet this could have important conservation implications. Our study aimed to (i) compare the diet of I. o. obesulus at novel and remnant sites; and (ii) attain knowledge of hypogeal fungal diversity in these different contexts. We collected 133 bandicoot scats over 23 months and examined both broad diet composition and diversity of fungi consumed. Bandicoot diet differed between site types; in particular, ants were more prominent in scats from remnant sites, while millipedes and seeds were more prominent in scats from novel sites. All scats contained fungal spores, with hypogeal taxa comprising at least 35 of the 78 ‘morphotypes’ found at novel sites and 28 of the 59 detected at remnant sites. Fewer samples were collected at remnant sites, but they appeared to contain a greater richness of hypogeal fungi per scat. We did not detect any differences in fungal composition between site types. However, our sampling effort was insufficient to estimate true morphotype richness at either site type. Our study highlights the adaptable generalist diet of the southern brown bandicoot, as well as the likely under-appreciated diversity of hypogeal fungi that can occur in highly modified, novel ecosystems.     

The edible katydid Ruspolia differens is a selective feeder on the inflorescences and leaves of grass species

Ruspolia differens (Serville) (Orthoptera: Tettigoniidae, Conocephalinae) (its common names including ‘African edible bush‐cricket’, ‘edible grasshopper’, and ‘nsenene’) is an important source of food for humans in East Africa, but its ecology and biology are poorly understood. We explored the host plants of R. differens with a series of no‐choice and multiple‐choice laboratory experiments using 18 local common grass and sedge species in Uganda. In no‐choice experiments, the degree of acceptance differed significantly among the studied plant species, but in only three species were leaves rejected and in one species were inflorescences rejected. The pattern of acceptance among plant species was different in the local vs. swarming populations. Leaves were generally more accepted by the local population, whereas inflorescences were generally more accepted by the swarming population. Both leaves and inflorescences were more readily accepted by males than by females. According to the multiple‐choice experiments, R. differens preferred inflorescences over leaves. Our results demonstrate that R. differens is a facultatively oligophagous grass‐specialist, which has a clear preference for certain grass or sedge species (especially inflorescences), but it accepts many host plants if the preferred ones are not available. To preserve viable natural populations of R. differens in East Africa in the long term, our results draw special attention to the availability of grasslands where accepted and preferred host plants are available year‐round.     

Biochemical and epigenetic changes in phytoplasma‐recovered periwinkle after indole‐3‐butyric acid treatment

Aim: To elucidate the possible mechanism of phytoplasma elimination from periwinkle shoots caused by indole‐3‐butyric acid (IBA) treatment. Methods and Results: It has been shown that a transfer of in vitro‐grown phytoplasma‐infected Catharanthus roseus (periwinkle) plantlets from medium supplemented with 6‐benzylaminopurine (BA) to one supplemented with IBA can induce remission of symptoms and even permanent elimination of ‘Candidatus Phytoplasma asteris’ reference strain HYDB. Endogenous auxin levels and general methylation levels in noninfected periwinkles, periwinkles infected with two ‘Candidatus Phytoplasma’ species and phytoplasma‐recovered periwinkles were measured and compared. After the transfer from cytokinin‐ to auxin‐containing media, healthy shoots maintained their phenotype, methylation levels and hormone concentrations. Phytoplasma infection caused a change in the endogenous indole‐3‐acetic acid to IBA ratio in periwinkle shoots infected with two ‘Candidatus Phytoplasma’ species, but general methylation was significantly changed only in shoots infected with ‘Ca. P. asteris’, which resulted in the only phytoplasma species eliminated from shoots after transfer to IBA‐containing medium. Both phytoplasma infection and treatment with plant growth regulators influenced callose deposition in phloem tissue, concentrations of photosynthetic pigments and soluble proteins, H₂O₂ levels and activities of catalase (CAT) and ascorbate peroxidase (APX). Conclusion: Lower level of host genome methylation in ‘Ca. P. asteris’‐infected periwinkles on medium supplemented with BA was significantly elevated after IBA treatment, while IBA treatment had no effect on cytosine methylation in periwinkles infected with ‘Candidatus Phytoplasma ulmi’ strain EY‐C. Significance and Impact of the Study: Hormone‐dependent recovery is a distinct phenomenon from natural recovery. As opposed to spontaneously recovered plants in which elevated peroxide levels and differential expression of peroxide‐related enzymes were observed, in hormone‐dependent recovery changes in global host genome, methylation coincide with the presence/absence of phytoplasma.     

Establishment of woody species across 26 years of revegetation on a Queensland coal mine

The establishment success of woody plant species at 56 revegetation sites, four to 26 years old, across the Meandu open‐cut coal mine in south‐east Queensland was assessed. The revegetation process involved returning stockpiled topsoil, deep ripping and mechanical sowing of a mix of native seeds. Blakes Wattle (Acacia blakei) and less often Black Wattle (A. leiocalyx), both primarily derived from respread topsoil seed, dominate the vegetation canopy at 59% and 20% of revegetation sites, respectively. The additional sowing of seeds of many tree and shrub species within the sites has had limited success with most failing to persist or grow well. Revegetation management, for example selective thinning of acacias (Acacia spp.) saplings within the first 5 years is recommended to release the competition pressure on the poorly performing tree species. This will also allow opportunities for other less well represented shrub and herb species to persist. This study has shown that a range of tree and shrub species, including Eucalyptus spp., are performing poorly under the current revegetation regime, suggesting adjustments to revegetation species selection and/or methodologies are needed. The natural colonization of woody native species within the sites from nearby remnant vegetation is shown to be limited to only four species, and therefore is unlikely to significantly supplement the species diversity of the revegetation.     

Persistent soil seed banks in old-growth Hyrcanian Box tree (Buxus hyrcana) stands in northern Iran

Little is known about the soil seed bank and the influence of plant communities on the interaction between the seed bank and aboveground vegetation in the Hyrcanian temperate deciduous forest. We surveyed species composition and diversity of the persistent soil seed bank and the aboveground vegetation in six community types in old-growth Hyrcanian Box tree (Buxus hyrcana) stands in northern Iran. Fifty-two species with an average of 3,808 seeds/spores m⁻² germinated; forbs accounted for 64% of the seed bank flora. Thirty-four species in the aboveground vegetation were not presented in the seed bank, 32 species in the seed bank were not found in the vegetation, and 20 species were in both. The dominant tree species were Diospyros lotus and Alnus subcordata with an average of 17 and 4.6 seeds m⁻², respectively. Our results suggest that (1) vernal geophytes and shade-tolerant perennials are not incorporated in the seed bank, (2) early successional species are well represented in the seed bank, (3) plant community type has significant impacts on seed bank densities, and seed bank richness and diversity were significantly related to presence/absence of Box tree in the aboveground vegetation. The persistent seed bank contained species that potentially have a negative impact on the regeneration of forests, thus forest managers should retain old-growth Hyrcanian Box tree stands to conserve disturbance-sensitive indicator forest species.     

Molecular identification of diverse ‘Candidatus Phytoplasma’ species associated with grapevine decline in Iran

Grapevine (Vitis vinifera) is one of the most important fruits in Iran where the provinces of Qazvin, Lorestan and Markazi are main producers. During 2013–2015, vineyards located in these provinces were surveyed to verify the presence of phytoplasma. The sample collection was based on symptomatology including decline, leaf yellowing and shortening of internodes. Total DNA was extracted from symptomatic and symptomless grapevine samples and used in nested‐polymerase chain reaction (PCR) assays with phytoplasma ribosomal primers (P1/Tint followed by R16F2n/R2, R16mF1/mR1, R16(I)F1/R1 or 6R758f/16R1232r). Nested‐PCR products were obtained only for symptomatic samples while samples from symptomless plants yielded no PCR products. Restriction fragment length polymorphism (RFLP) analyses with Tru1I, TaqI and Tsp509I and direct sequencing of amplicons followed by phylogenetic analyses indicated the presence of ‘Candidatus Phytoplasma fraxini’, ‘Ca. P. aurantifolia’, ‘Ca. P. solani’ and ‘Ca. P. phoenicium’‐related strains. In Marzaki province, there ‘Ca. P. aurantifolia’ strains were mainly detected, while in the other two provinces, all the four ‘Candidatus species’ were identified with the prevalence of ‘Ca. P. solani’‐related strains. In both provinces in one case, mixed phytoplasma infection was also detected by RFLP analyses. The presence of different phytoplasmas in positive samples indicates great phytosanitary significance due to grapevine economic importance for country. Grapevine phytoplasma infection represents a threat for other crops suggesting grapevine as alternative host species for the phytoplasmas already reported in Iran, while the ‘Ca. P. fraxini’ is for the first time identified in Iran.     

Speciation in a keystone plant genus is driven by elevation: a case study in New Guinean Ficus

Much of the world's insect and plant biodiversity is found in tropical and subtropical ‘hotspots’, which often include long elevational gradients. These gradients may function as ‘diversity pumps’ and contribute to both regional and local species richness. Climactic conditions on such gradients often change rapidly along short vertical distances and may result in local adaptation and high levels of population genetic structure in plants and insects. We investigated the population genetic structure of two species of Ficus (Moraceae) along a continuously forested elevational gradient in Papua New Guinea. This speciose plant genus is pollinated by tiny, species‐specific and highly coevolved chalcid wasps (Agaonidae) and represented by at least 73 species at our study gradient. We present results from two species of Ficus sampled from six elevations between 200 m and 2700 m a.s.l. (almost the entire elevational range of the genus) and 10 polymorphic microsatellite loci. These results show that strong barriers to gene flow exist between 1200 m and 1700 m a.s.l. Whereas lowland populations are panmictic across distances over 70 km, montane populations can be disjunct over 4 km, despite continuous forest cover. We suggest that the limited gene flow between populations of these two species of montane Ficus may be driven by environmental limitations on pollinator or seed dispersal in combination with local adaptation of Ficus populations. Such a mechanism may have wider implications for plant and pollinator speciation across long and continuously forested elevational gradients if generalist insect pollinators and vertebrate seed dispersers also form populations based on elevation.