Minuartia Verna Research Articles

Contrasting soil‐ and canopy‐nurse effects in metalliferous systems may be explained by dominant plant functional strategies

Abstract Plant‐plant interaction studies in metalliferous systems have focused either on the role of facilitation or on negative effects of elemental allelopathy. However, no studies have investigated both of these effects in the same system, and their relationships with the functional strategy of the nurse species, although this is crucial for the ecological restoration of polluted sites. We assessed the effects of two dominant nurse species, with apparent contrasting strategies, on two target species on a slag heap in the Pyrenees (France). We quantified both long‐term soil‐engineering and short‐term canopy effects on the growth of two target species. We also measured morphological traits and leaf metal concentration of the two nurse species and their effects on air moisture, temperature and vapour pressure deficit. Nurse functional strategies, as inferred from morphological traits and leaf metal concentration seem to drive their long‐term soil engineering effects on target species: Gypsophila repens, the relative larger and more exploitative species with high leaf metal concentration, had negative long‐term effects likely due to elemental allelopathy, whereas Minuartia verna, the relative smaller and more conservative species with lower amount of metals in leaves, had neutral long‐term effects. Although Gypsophila repens had a slightly stronger positive effect on microclimate than Minuartia verna, this did not turn into higher short‐term effects for the target species. Synthesis and applications: Our study highlights the diverse long and short‐term nurse effects on companion species in metalliferous systems. Different nurse species can improve the performance of companion species by mitigation of climatic stress, and ultimately help speed‐up the restoration of polluted environments. However, species status regarding leaf metal accumulation has to be verified. For species having a higher metal concentration in their leaves, positive microclimatic effects may be offset by local increase of soil contamination on the long‐term.

Native Habitat and Seed Germination Characteristics of Minuartia verna var. coreana (Nakai) H. Hara, a Rare and an Endemic Species in the Korean Peninsula

Native Habitat and Seed Germination Characteristics of Minuartia verna var. coreana (Nakai) H. Hara, a Rare and an Endemic Species in the Korean Peninsula

Does geography, evolutionary history or ecology drive ploidy and genome size variation in the Minuartia verna group (Caryophyllaceae) across Europe?

Polyploidization, a key driver of plant diversification, is believed to have interacted with Pleistocene climatic oscillations and local ecological factors, leading to a complex spatio-ecological mosaic of diploid and polyploid populations. The typical ecogeographic pattern in European plants involves spatially restricted diploids growing in southern regions, interpreted as glacial refugia, and their widespread polyploid derivatives occupying larger and more northerly situated ranges with harsher environments. Whether this is true for individual ploidy-variable groups is, however, largely unknown because we lack sufficiently detailed investigations of ploidy-variable plant groups jointly applying cytological, ecological and genetic methods. We assessed ploidy and genome size variation, elevational and edaphic preferences, and plastid DNA variation within the Minuartia verna aggregate, a group of low-competitive heliophilous plants growing from the Mediterranean to Arctic Europe. Contrary to the expectations, tetraploids have a restricted distribution (Southern Europe) and inhabit a relatively narrow environmental niche. The distribution of diploids, on the other hand, spans the full range of conditions, including climatic (i.e. highest elevations and latitudes) and edaphic extremes (i.e. toxic serpentine and metalliferous substrates). The distribution pattern of the two ploidies could be explained by their distinct evolutionary histories, suggesting expansion of the diploid-dominated haplotype group accompanied by long-term persistence and local differentiation of tetraploids in refugia in the Balkan Peninsula. In summary, our study contradicts the prevailing view of polyploids as successful colonizers of novel and challenging habitats and points to the importance of combining ecological and genetic data when studying ploidy-variable species complexes.

Metallophytes and thallium hyperaccumulation at the former Raibl lead/zinc mining site (Julian Alps, Italy)

An ecological survey of metallophytes belonging to the Thlaspietum cepaeifolii plant community was carried out at the former Raibl lead and zinc mining site (Julian Alps, Italy). The aims of this work were to evaluate metal hyperaccumulation and to determine whether it was restricted to a single element or, instead, involved multiple elements. The concentrations of Cd, Pb, Tl and Zn were measured in specimens of Alyssum wulfenianum, Biscutella laevigata subsp. laevigata, Minuartia verna and Thlaspi rotundifolium subsp. cepaeifolium collected from native and mining soils, mine tailings and stream banks. Cadmium hyperaccumulation was not demonstrated, whereas in the case of Pb and Zn contradictory results were obtained. Thallium hyperaccumulation was strongly confirmed in B. laevigata subsp. laevigata (up to 32,661 mg kg−1 of Tl in shoots and bioconcentration factor > 1). Surprisingly, this was also discovered in A. wulfenianum and M. verna (up to 1934 and 3632 mg kg−1 of Tl in shoots, respectively, and bioconcentration factor >1). Multiple metal hyperaccumulation was verified in B. laevigata subsp. laevigata (Pb and Tl), M. verna and T. rotundifolium subsp. cepaeifolium (Pb, Tl, and Zn) although it could not be confirmed in any of these species when coefficients calculated on shoot concentration of the elements were considered.

Root plasticity in Mediterranean herbaceous species

Root plasticity has been largely studied on herbaceous species of north European temperate flora and is defined as the ratio between root depth in dry soils and root depth in wet soils. In summer dry habitats such as Mediterranean environments, the soil water deficit is a common feature to which root systems of plant species should adapt to improve their ecological efficiency. The aim of this study was to compare root plasticity in annual Mediterranean species that regenerate exclusively from seeds, and herbaceous perennial Mediterranean species that use dual regeneration strategies. Root plasticity of ten herbaceous species, six perennials and four annuals, was compared in this study. The annuals species studied occur in lowland Mediterranean grasslands referred to Tuberarietea guttatae class (Dasypyrum villosum, Lophochloa pubescens, Ornithopus compressus, Rumex bucephalophorus), while the perennial species occur in montane sub-Mediterranean grasslands referred to Festuco brometea (Bromus erectus, Festuca ovina., Lotus corniculatus., Minuartia verna, Sanguisorba minor, Thymus longicaulis). The examined species were subjected to water stress according to standard methods applied in comparative ecology, i.e., half of the seedlings of each species received 20 ml de-ionized water daily for three weeks, while the other half did not. After seedling harvesting the following parameters were analysed: (i) total root length; (ii) root length in the first 10 cm of soil; (iii) shoot height; (iv) root biomass in the first 10 cm of soil; (v) shoot biomass; (vi) shoot and root plasticity. Results show that root plasticity increased significantly in dual-regenerator sub-Mediterranean mountain species.

Koeleria macrantha (Ledeb.) Schultes (K. alpigena Domin, K. cristata (L.) Pers. pro parte, K. gracilis Pers., K. albescens auct. non DC.)

<i>Koeleria macrantha</i> (Ledeb.) Schultes (<i>K. alpigena</i> Domin, <i>K. cristata</i> (L.) Pers. pro parte, <i>K. gracilis</i> Pers., <i>K. albescens</i> auct. non DC.)

Accumulation of heavy metals in plants grown on mineralised soils of the Austrian Alps

A field survey of higher terrestrial plants growing on 18 metalliferous sites of the Austrian Alps was conducted to identify species accumulating exceptional large concentrations of Cd, Cu, Ni, Pb and Zn in shoots. Minuartia verna ( Caryophyllaceae) was confirmed and Biscutella laevigata ( Brassicaceae) newly identified as hyperaccumulators of Pb (>1000 mg kg −1 Pb in shoots). Metal concentrations in shoots exceeded those in roots. Cadmium concentrations detected in shoots of Thlaspi rotundifolium ssp. cepaeifolium (up to 108 mg kg −1), Cardaminopsis halleri (up to 80 mg kg −1), Biscutella laevigata (up to 78 mg kg −1) and Minuartia verna (up to 59 mg kg −1) may represent hyperaccumulation. In addition, populations of Thlaspi goesingense (up to 12400 mg kg −1 Ni) and Thlaspi rotundifolium ssp. cepaeifoliium (up to 1934 mg kg −1 Pb) were confirmed to be hyperaccumulators. The strategy of neighboring Thlaspi rotundifolium ssp. cepaeifolium populations to tolerate high Pb and Zn was found to switch from hyperaccumulation at moderate and large, to exclusion at very large metal concentrations in soil. Metal partitioning in soils determined by sequential extraction gives evidence for large proportions of potentially mobile fractions. Metals stored in shoots typically do not exceed the soil metal pool in fractions 1 (exchangeable) and 2 (readily mobile). There is evidence that hyperaccumulation may be associated with depressed translocation of K from roots to shoots. Under natural conditions metals accumulated in shoots are annually recycled to the soil, hyperaccumulators do not necessarily rely on metal phases less soluble than fractions 1 and 2. These should be considered in future development of phytoremediators, because after extraction of these phases by harvesting shoots, further metal removal may be limited by dissolution kinetics of oxides and silicates.

Silicon Storage in Selected Dicotyledons

Abstract:Silicon was localized in some dicotyledons (Minuartia verna, Silene cucubalus, Thlaspi coerulescens, Viola calaminaria, Nicotiana tabacum, Pisum sativum) by analytical transmission electron microscopy as apoplastic crystalline inclusions of SiO2 in intercellular spaces of the leaf parenchyma, between cell wall and plasma membrane and inside the vacuoles. Ca‐silicate, and in some plants Sn‐silicate, forms the peripheral parts of the crystalline inclusions. These unstable compounds are converted spontaneously in the plant cells into the more stable SiO2, which forms the central part of all crystalline inclusions. The function of silicon in these plants is discussed.

Heavy metal tolerance of Minuartia verna

Individuals of Minuartia verna ssp. hercynica, growing on heavy metal polluted soil of medieval mine dumps, accumulate remarkable concentrations of copper and zinc in their leaves. The cellular and intracellular distributions of heavy metals were investigated by conventional electron microscopy, EDX, ESI and EELS. Considerable amounts of Fe, Cu, Zn, and Al found on the leaf surface are excreted by hydrathodes. Intracellular spaces and cell walls of the leaf parenchyma contain Fe, Cu, Zn, and Pb, whereas no metals could be detected in the cytoplasm, vacuole or cellular organelles. High Si concentrations evident in vacuoles, cell walls and intercellular spaces are not directly involved in the detoxification of the heavy metals with one exception, zinc is precipitated as a Zn-silicate in the epidermal cell walls. The possible mechanisms of heavy metal tolerance in Minuartia and the role of Si in these processes are discussed.

Heavy-metal uptake and distribution in Silene vulgaris and Minuartia verna growing on mining-dump material containing lead and zinc

Plant and soil samples from a mining area in Carinthia (Austria) were investigated for their heavy metal content. In the soil surrounding roots of plants (Minuartia verna and Silene vulgaris) growing on the mining dumps, high concentrations of lead and zinc are to be expected. The two species (Minuartia and Silene) show very different heavy metal concentrations in their above- and belowground organs. From these observations it can be concluded that the divergent distribution of heavy metals within the plants is an important mechanism of tolerance to heavy metals.

The distribution of Minuartia verna and Thlaspi alpestre in the British Isles in relation to 13 soil metals

The plant-communities from habitats of the metallophyte species Minuartia verna and Thlaspi alpestre (T. caerulescens) at sites disturbed and undisturbed by mining are described. Four communities were delineated by cluster and principal component analysis. Group 1 comprised species-poor communities on disturbed non-calcareous soils; group 2, relatively species-rich communities on disturbed calcareous soils; group 3, species-rich communities in the main on undisturbed calcareous soils. Group 4 consisted of species-rich communities with an alpine element, in damp habitats on base-rich soils derived from igneous rocks. Total and exchangeable elements As, Ba, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb and Zn were determined for the soils of these sites. Levels of soil Ca, Cd, Pb and Zn accounted for most of the variation along the first axis of the PCA and soil nutrient levels were probably the main predictor along the second.

Ökologische Untersuchungen auf einer auf metallhaltigem Boden entwickelten Wiese

AbstractEcological Investigation of a Meadow Developed on a Metal‐Rich SoilThe floristic structure of a meadow over a copper‐rich soil was studied, and four different stages of vegetation succession were described. The following species dominate over the different stages: Minuartia verna, Thymus sibthorpii, Rumex acetosella and Chrysopogon gryllus. Soil analysis showed that the most undeveloped soil of the Minuartia stage exhibits the highest concentration of Cu and of twelve other elements, while the mature soil of the Chrysopogon stage exhibits the highest concentrations of Al, Ca, Na and Ni.An inverse relationship was found between the concentrations of Cu in the soil and the number of species in the forty sampling quadrats. Plant analysis showed that Minuartia verna and Rumex acetosella accumulate more copper in their tissues than the other two dominant species.

The effect of geographical isolation on enzyme polymorphism of heavy-metal tolerant populations of Minuartia verna (L) Hiern.

Isolated metal-tolerant populations of Minuartia verna exhibit a remarkable amount of genetic polymorphism (P = 0.44). Different enzyme variants were fixed in different populations. No evidence was found for a genotype-environment relation for malate metabolizing enzymes and Zn-tolerant populations. An activation energy analysis of malate dehydrogenase did not support the concept of an adaptive strategy related to temperature between alpine and non-alpine populations. No good evidence was found for a multilocus genotype association either. The pattern of isoenzyme distribution within and between populations could be explained only by long distance isolation and founder effects.

Biogeochemical studies of areas of sulphide mineralization in Northern Greece

Biogeochemical and geobotanical studies have been carried out in several areas of sulphide mineralization in northern Greece. In porphyry copper areas, mineralized zones can be delineated by mapping the distribution of Minuartia verna, or by measuring the copper content of Rumex acetosella and Thymus sibthorpii. Elevated levels of molybdenum in the soil are indicated by higher concentrations of this element in T. sibthorpii. In an area of barite mineralization, biogeochemical methods were not useful in showing the barium distribution, but did provide an indication of the associated lead mineralization. The appearance of the nickel accumulator Alyssum murale near a zone of antimonite mineralization seems to be related to sporadic occurrences of ultrabasic rocks nearby.

Rumex acetosella L. and Minuartia verna (L.) Hiern as geobotanical and biogeochemical indicators for ore deposits in northern Greece

Copper, zinc, lead, manganese, arsenic, iron, cadmium and molybdenum were measured in specimens of Rumex acetosella and Minuartia verna and in soils where these plants grow. In Macedonia and the Chalkidiki peninsula both plants occur on newly investigated sulphide-mineralized ground. There are highly significant correlations between the levels of copper, zinc and lead in the plants and those in the soils. Where high concentrations of arsenic occur in the soil, this is also reflected in the plants. Because of the common association of gold and arsenic, it is suggested that analysis of Rumex and Minuartia for arsenic may be a useful prospecting tool since most of the ore occurrences in the Serbomacedonian massif are auriferous. The high levels of manganese in both plants from a manganese mineralized area indicate a strong possibility of using biogeochemical methods to define zones of some types of mineralization of this element also.

Geobotany-biogeochemistry for mineral exploration of sulphide deposits in northern Greece — Heavy metal accumulation by Rumex acetosella L. and Minuartia verna (L.) Hiern

Rumex acetosella and Minuartia verna are confined to mineralized ground in Macedonia. These plants contain relatively high concentrations of heavy metals such as copper, zinc, lead and manganese, and are to that extent, valuable indicators of sulphide mineralization, either pyrite + chalcopyrite or pyrite + chalcopyrite + sphalerite + galena. There is a direct relationship between the metal content of the plant ash and the metal content of the soils and mineralized substrate.

The occurrence and need for conservation of metallophytes on mine wastes in Europe

Metalliferous substrates are important in the distribution of various plants such asArmeria maritima, Minuartia verna, Thlaspi alpestre, Silene maritima andCochlearia officinalis, in parts of the United Kingdom. Metalliferous substrates are similarly important for a slightly different assemblage of metallophytes in the Aachen-Liege orefield in Belgium and Germany. The significance of metalliferous substrates in the distribution of the metallophytes varies from orefield to orefield and this is investigated. Certain sites, by virtue of their environmental and species diversity, are outstanding as habitats for the metallophytes and some of these are described. Observations on the importance and problems of the conservation of the metallophyte habitats are included.

PROBLEMS OF INTERPRETING THE RELATIONSHIP BETWEEN THE AMOUNTS OF LEAD AND ZINC IN PLANTS AND SOIL ON METALLIFEROUS WASTES

SUMMARYThe lead and zinc contents of shoot material of Agrostis tennis, Festuca ovina and Minuartia verna and of the soil in which they were growing at an abandoned lead‐mining area on Grassington Moor, Yorkshire, England were determined. The relationship between the zinc contents of shoot material and soil was broadly linear. There was little increase, however, in the lead content of the shoot material over the range 500‐20000 μg g−1 lead in the soil. Above this value the lead content of the shoot material increased markedly. There were large differences between samples in the metal contents of the shoot material collected from soils having the same metal contents. Possible reasons for this variation are discussed and specific suggestions for future comparative work are made.

Note critiche sulla flora d'Italia. II. Il gruppo di Minuartia verna

Abstract Critical notes on the flora of Italy. II. The Minuartia verna group. The following paper contains a re-examination of the Minuartia verna–complex in Italy based on a revision of herbarium-specimens and observations in nature. The author proposes to divide this polymorphic species into 4 subspecies. Two of them (subsp. verna and subsp. collina) are largely corresponding to the opinion of earlier authors. The subsp. attica is also represented in the flora of Southern Italy, but Italian populations are slightly different from those of Greece (which must be regarded as typical). The subsp. grandiflora living in a small area in Sicily, which was incompletely known, is described and its relations to the other subspecies are discussed.