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See detailSpecialized edaphic niches of threatened copper endemic plant species in the D.R. Congo: implications for ex situ conservation
Boisson, Sylvain ULiege; Faucon, M.-P.; Le Stradic, Soizig ULiege et al

in Plant and Soil (2017)

Background and aims: Copper (Cu) rich soils derived from rocks of the Katangan Copperbelt in the south-eastern Democratic Republic of Congo (DRC) support a rich diversity of metallophytes including 550 ... [more ▼]

Background and aims: Copper (Cu) rich soils derived from rocks of the Katangan Copperbelt in the south-eastern Democratic Republic of Congo (DRC) support a rich diversity of metallophytes including 550 heavy metal tolerant; 24 broad Cu soil endemic; and 33 strict Cu soil endemic plant species. The majority of the plant species occur on prominent Cu hills scattered along the copperbelt. Heavy metal mining on the Katangan Copperbelt has resulted in extensive degradation and destruction of the Cu hill ecosystems. As a result, approximately 80 % of the strict Cu endemic plant species are classified as threatened according to IUCN criteria and represent a conservation priority. Little is known about the soil Cu tolerance optimum of the Cu endemic plant species. The purpose of this study was to quantify the soil Cu concentration (Cu edaphic niche) of four Cu endemic plant species to inform soil propagation conditions and microhabitat site selection for planting of the species in Cu hill ecosystem restoration. Methods: The soil Cu concentration tolerance of Cu endemic plant species was studied including Crotalaria cobalticola (CRCO); Gladiolus ledoctei (GLLE); Diplolophium marthozianum (DIMA); and Triumfetta welwitschii var. rogersii (TRWE-RO). The in situ natural habitat distributions of the Cu endemic plant species with respect to soil Cu concentration (Cu edaphic niche) was calculated by means of a generalised additive model. Additionally, the seedling emergence and growth of the four Cu endemic plant species in three soil Cu concentrations was tested ex situ and the results were compared to that of the natural habitat soil Cu concentration optimum (Cu edaphic niche). Results: CRCO exhibited greater performance on the highest soil Cu concentration, consistent with its calculated Cu edaphic niche occurring at the highest soil Cu concentrations. In contrast, both DIMA and TRWE-RO exhibited greatest performance at the lowest soil Cu concentration, despite the calculated Cu edaphic niche occurring at moderate soil Cu concentrations. GLLE exhibited equal performances in the entire range of soil Cu concentrations. Conclusions: These results suggest that CRCO evolved via the edaphic specialization model where it is most competitive in Cu hill habitat with the highest soil Cu concentration. In comparison, DIMA and TRWE-RO appear to have evolved via the endemism refuge model, which indicates that the species were excluded into (i.e., took refuge in) the lower plant competition Cu hill habitat due to their inability to effectively compete with higher plant competition on normal soils. The soil Cu edaphic niche determined for the four species will be useful in conservation activities including informing soil propagation conditions and microhabitat site selection for planting of the species in Cu hill ecosystem restoration. © 2016 Springer International Publishing Switzerland [less ▲]

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See detailRegeneration after fire in campo rupestre: Short- and long-term vegetation dynamics
Le Stradic, Soizig ULiege; Hernandez, P.; Fernandes, G. W. et al

in Flora: Morphology, Distribution, Functional Ecology of Plants (2017)

The Cerrado (Brazilian savanna) is the second largest biome in Brazil, covering 22% of the country, and campo rupestre is one of the most biodiverse ecosystem. Campo rupestre are extremely old mountaintop ... [more ▼]

The Cerrado (Brazilian savanna) is the second largest biome in Brazil, covering 22% of the country, and campo rupestre is one of the most biodiverse ecosystem. Campo rupestre are extremely old mountaintop tropical ecosystems, composed of a mosaic of herbaceous, shrubland and savanna vegetation, generally located above 900. m above sea level characterized by shallow, acidic and nutrient-poor soils. In the context of increased land-use changes, effective conservation and management projects appear necessary to guarantee the conservation of these ecosystems. Although fire is a natural disturbance in campo rupestre, the effects of fire on vegetation dynamics remain poorly understood. Our objective was to assess the effects of fire on vegetation recovery and plant composition on both the short- and long-term in the main herbaceous vegetation types: the sandy and stony grasslands. We monitored plant community composition before and after a wildfire in order to assess the short-term vegetation recovery. Diachronic analyses of grasslands burnt at various dates were used to understand the effects of fire on the long-term vegetation dynamics. Our results highlighted a rapid recovery of campo rupestre vegetation after wildfires, suggesting a high adaptation to fire of plant communities. We did not find a significant variation in species richness of sandy grasslands according to time after fire, whereas higher species richness was observed in the recently burnt stony grasslands. No change in plant composition of campo rupestre in response to fire was highlighted, probably due to the high heterogeneity of this ecosystem. After fire, biomass gradually increased over time in both vegetation types. High biomass accumulation could lead to stronger fires. Further studies are necessary to understand the relationship between biomass accumulation and fire intensity in campo rupestre in order to set up adapted fire management strategies to conserve campo rupestre biodiversity. © 2017 Elsevier GmbH. [less ▲]

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See detailUsing phytostabilisation as a way to conserve threatened endemic species from the Southeastern D.R. Congo
Boisson, Sylvain ULiege; Le Stradic, Soizig ULiege; Seleck, Maxime ULiege et al

Conference (2016, June 22)

Metalliferous outcrops of the southeastern Democratic Republic of Congo are recognized as some of the largest copper-cobalt deposits of the world. They support unique vegetation with around 600 ... [more ▼]

Metalliferous outcrops of the southeastern Democratic Republic of Congo are recognized as some of the largest copper-cobalt deposits of the world. They support unique vegetation with around 600 metallophyte species including rare and endemic species. Since 1900s, the exploitation of the Cu-Co outcrops in D.R. Congo has considerably increased, impacting environment and putting public health at risk. Phytostabilisation is a suitable technology to decrease the bioavailability of heavy metals in highly polluted soils. This technic has been successfully implemented in the vicinity of Lubumbashi with the grass Microchloa altera. The long term maintenance of such technic requires a good understanding of the interspecific relationship like competition and facilitation. This study aims to test the success of establishment of four herbaceous species from the southeastern DRC presenting conservation priority and to assess the potential role of M. altera as nurse plant in this context. Two annual species and two perennial species were sown in experimental design with soil amendments crossed with vegetation cover. The emergence, the growth and the survival were followed during the vegetation season and the resprout was measured for perennial species. M. altera had a distinct effect on the emergence and the survival of the annual and perennial species but affected negatively the growth of individuals for all species. [less ▲]

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See detailGrowth-survival trade-off in shrub saplings from Neotropical mountain grasslands
Negreiros, D.; Fernandes, G. W.; Efremova, A. A. et al

in South African Journal of Botany (2016), 106

The growth-survival trade-off plays a central role in the coexistence of species-rich plant communities. While recurrently described in forest tree communities primarily limited by light availability ... [more ▼]

The growth-survival trade-off plays a central role in the coexistence of species-rich plant communities. While recurrently described in forest tree communities primarily limited by light availability, this trade-off is still poorly documented in grassland and savanna vegetation. In this comparative study we planted in a quartzitic degraded site eight-month-old saplings of eleven shrub species native from constrained mountain grassland (Brazilian rupestrian grassland). We measured the relative growth rate (RGR) during a 30-week time interval, leaf water potential under dry and wet conditions, and related these traits to the species survival. The interspecific comparison between the saplings performance clearly showed the classic growth-survival trade-off. The RGR expressed in stem diameter and aboveground biomass explained respectively 62% and 40% of the variation in saplings' survival one year after planting, and respectively 65% and 44% of the variation in survival 4.5 years after planting. This trade-off was not related to either leaf water potential or final size in aboveground biomass and basal stem diameter. Our results corroborate the view that the growth-survival trade-off is universally applicable, even in non-forest communities such as grasslands and savannas subjected to severe nutritional deficiency, pronounced seasonal drought, and high light incidence. The environmental differences in micro-habitats that compose rupestrian grasslands should distinctly favour species with contrasting strategies of growth and survival, thus contributing to niche partitioning and coexistence in this species-rich ecosystem. © 2016 South African Association of Botanists. [less ▲]

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See detailCopper tolerance of three Crotalaria species from southeastern D.R. Congo at the early development stage [Tolérance au cuivre de trois espèces de Crotalaria de l’Arc Cuprifère Katangais dans les premiers stades de croissance]
Boisson, Sylvain ULiege; Le Stradic, Soizig ULiege; Commans, M. et al

in Biotechnologie, Agronomie, Société et Environnement (2016), 20(2), 151-160

Description of the subject. Microevolutionary processes in metallophytes established on copper enriched soils can lead to a diversity of plant species showing distinct tolerance capacities among genus ... [more ▼]

Description of the subject. Microevolutionary processes in metallophytes established on copper enriched soils can lead to a diversity of plant species showing distinct tolerance capacities among genus. Researches about the relationship between these endangered plants and soil copper concentrations are critical in order to improve ex situ conservation methods in southeastern Democratic Republic of Congo (Katangan Copperbelt). Objectives. The aim of the study was to test the effect of copper on the germination and root elongation of three Crotalaria species naturally occurring along a natural copper gradient. The hypothesis is that copper concentrations have different effects on germination and root elongation according to the species of Crotalaria genus. Method. Three species were selected: Crotalaria cobalticola, Crotalaria peschiana and Crotalaria cornetii, occurring on soils with the highest to the lowest copper concentrations respectively. Germination and root elongation tests were performed in vitro (MS vitamin-enriched medium) in six copper mediums ranging from 0 to 125 μM Cu2+. Results. No significant differences in germination percentage were observed according to the copper concentrations. Crotalaria cornetii had the lowest germination percentage. Root elongation of C. peschiana did not differ with copper concentration, but root elongation of C. cobalticola was higher at the greatest copper concentration (125 μM Cu2+). Conclusions. Even if C. cobalticola presented better growth at highest Cu concentrations, it appeared that C. cobalticola and C. peschiana do not require copper for their early stages of development and could thus be conserved in non-contaminated substrate. Crotalaria cornetii seemed to present a physical seed dormancy. © 2016, FAC UNIV SCIENCES AGRONOMIQUES GEMBLOUX. All rights reserved. [less ▲]

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See detailPotential of copper-tolerant grasses to implement phytostabilisation strategies on polluted soils in South D. R. Congo: Poaceae candidates for phytostabilisation
Boisson, Sylvain ULiege; Le Stradic, Soizig ULiege; Collignon, Julien et al

in Environmental Science and Pollution Research (2016)

Phytostabilisation (i.e. using plants to immobilise contaminants) represents a well-known technology to hamper heavy metal spread across landscapes. In Katanga (D. R. Congo), Microchloa altera, a tolerant ... [more ▼]

Phytostabilisation (i.e. using plants to immobilise contaminants) represents a well-known technology to hamper heavy metal spread across landscapes. In Katanga (D. R. Congo), Microchloa altera, a tolerant grass from the copper hills, was recently identified as a candidate species to stabilise copper in the soil. More than 50 grasses compose this flora, which may be studied to implement phytostabilisation strategies. However, little is known about their phenology, tolerance, reproductive strategy or demography. The present study aims to characterize the other Poaceae that may be used in phytostabilisation purposes based on the following criteria: their ecological distribution, seed production at two times, abundance, soil coverage and the germination percentage of their seeds. We selected seven perennial Poaceae that occur on the copper hills. Their ecological distributions (i.e. species response curves) have been modelled along copper or cobalt gradients with generalized additive models using logic link based on 172 presence/absence samples on three sites. For other variables, a total of 69 quadrats (1 m2) were randomly placed across three sites and habitats. For each species, we compared the number of inflorescence-bearing stems (IBS) by plot, the percentage of cover, the number of seeds by IBS and the estimated number of seeds by plot between sites and habitat. Three species (Andropogon schirensis, Eragrostis racemosa and Loudetia simplex) were very interesting for phytostabilisation programs. They produced a large quantity of seeds and had the highest percentage of cover. However, A. schirensis and L. simplex presented significant variations in the number of seeds and the percentage of cover according to site. [less ▲]

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See detailCopper tolerance of three Crotalaria species from southeastern D.R. Congo at the early development stage
Boisson, Sylvain ULiege; Le Stradic, Soizig ULiege; Commans, Morgane et al

in Biotechnologie, Agronomie, Société et Environnement (2016), 20(2), 151-160

Description of the subject. Microevolutionary processes in metallophytes established on copper enriched soils can lead to a diversity of plant species showing distinct tolerance capacities among genus ... [more ▼]

Description of the subject. Microevolutionary processes in metallophytes established on copper enriched soils can lead to a diversity of plant species showing distinct tolerance capacities among genus. Researches about the relationship between these endangered plants and soil copper concentrations are critical in order to improve ex situ conservation methods in southeastern Democratic Republic of Congo (Katangan Copperbelt). Objectives. The aim of the study was to test the effect of copper on the germination and root elongation of three Crotalariaspecies naturally occurring along a natural copper gradient. The hypothesis is that copper concentrations have different effects on germination and root elongation according to the species of Crotalaria genus.Method. Three species were selected: Crotalaria cobalticola, Crotalaria peschiana and Crotalariacornetii, occurring on soils with the highest to the lowest copper concentrations respectively. Germination and root elongation tests were performed in vitro (MS vitamin-enriched medium) in six copper mediums ranging from 0 to 125 μM Cu2+. Results. No significant differences in germination percentage were observed according to the copper concentrations. Crotalaria cornetii had the lowest germination percentage. Root elongation of C. peschiana did not differ with copper concentration, but root elongation of C. cobalticola was higher at the greatest copper concentration (125 μM Cu2+). Conclusions. Even if C. cobalticola presented better growth at highest Cu concentrations, it appeared that C. cobalticola and C. peschiana do not require copper for their early stages of development and could thus be conserved in non-contaminated substrate. Crotalariacornetii seemed to present a physical seed dormancy. [less ▲]

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See detailEcologia funcional de campos rupestres
Negreiros, Daniel; Le Stradic, Soizig ULiege; Fernandes, Geraldo Wilson

Conference (2015, September)

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See detailHow can phenology contribute to ecological restoration?
Buisson, Elise; Alvarado, Swanni; Le Stradic, Soizig ULiege et al

Conference (2015, August)

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See detailSpecies-rich anthropogenic grasslands and the problem of afforestation
Buisson, Elise; Le Stradic, Soizig ULiege; Alvarado, Swanni et al

Conference (2015, August)

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See detailCopperflora – an online species-level database of biology, ecology, geography of the flora from the Katangan Copperbelt (D.R. Congo) to manage their conservation
Boisson, Sylvain ULiege; Seleck, Maxime ULiege; Le Stradic, Soizig ULiege et al

Poster (2015, May 21)

Storage and accessibility to structured data are essential in all fields of scientific research. In ecology, conservation managers regularly use thousands qualitative and quantitative data from different ... [more ▼]

Storage and accessibility to structured data are essential in all fields of scientific research. In ecology, conservation managers regularly use thousands qualitative and quantitative data from different partners and studies. In recent years, online databases concerning climate, species traits and distribution have been developed but few offer a comprehensive tool for the management of species conservation at several steps. The Copperflora database was created in order to include a diversity of informations about species (taxonomy, habitats, phenology, pictures, distribution, etc.) but also information concerning seeds collection, conservation, monitoring and tests applied to target species. Copperflora is meant to be an interactive and a dynamic project enhancing the exchange of data. Our project also contributes to the advance in the understanding of metallophyte communities’ conservation and restoration projects. Our database structure is expected to be easily transferable to other conservation actions. [less ▲]

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See detailEtude de la flore spontanée de la carrière de Loën (Belgique) pour de futures restaurations
Pitz, Carline ULiege; Monty, Arnaud ULiege; Piqueray, Julien et al

Conference (2015, March 04)

Afin de maximiser le potentiel de biodiversité d’une carrière en fin d’exploitation deux options s’offrent au gestionnaire : (1) laisser les espèces recoloniser spontanément le site, (2) mettre en œuvre ... [more ▼]

Afin de maximiser le potentiel de biodiversité d’une carrière en fin d’exploitation deux options s’offrent au gestionnaire : (1) laisser les espèces recoloniser spontanément le site, (2) mettre en œuvre des appuis techniques à la restauration d’écosystèmes. Une méthode hybride associant une recolonisation naturelle et une assistance technique peut également être une opportunité pour le gestionnaire. La recolonisation spontanée des carrières peut, dans certains cas, créer une mosaïque d’habitats diversifiés pour des coûts faibles par rapport à des projets de réhabilitation ou de restauration couteux. Toutefois, l’intérêt biologique des habitats issus de successions spontanées peut fortement varier d’un site à l’autre en fonction de l’historique de gestion, des conditions climatiques et édaphiques locales, de l’isolement du site dans le paysage et du pool régional d’espèces présentes. Afin d’évaluer la nécessité ou non de mise en œuvre d’une restauration active d’habitats en carrière, il est nécessaire de caractériser les habitats issus de la succession spontanée ainsi que leur valeur biologique. L’évaluation de l’intérêt biologique d’un habitat prend en compte à la fois la diversité biologique locale (diversité alpha) et l’originalité des communautés présentes par rapport à un référentiel paysager (diversité béta). Ce projet a pour objectif de caractériser la flore recolonisant spontanément les zones xériques non exploitées dans une carrière située en Belgique (Loën, en région wallonne), du point de vue de la diversité spécifique et de la fonctionnalité écologique. Les communautés végétales ont été caractérisées au sein du site de Loën (diversité alpha) et d’un ensemble d’autres carrières représentatives de la diversité des contextes géographiques des carrières calcaires en Région wallonne (diversité béta). [less ▲]

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See detailVegetation composition and structure of some Neotropical mountain grasslands in Brazil
Le Stradic, Soizig ULiege; Buisson, Elise; Fernandes, Geraldo Wilson

in Journal of Mountain Science (2015), 12(4), 864-877

The description and understanding of plant communities is fundamental for the implementation of conservation or restoration programs, especially when these communities are highly threatened and need to be ... [more ▼]

The description and understanding of plant communities is fundamental for the implementation of conservation or restoration programs, especially when these communities are highly threatened and need to be restored. Campos rupestres, some Neotropical mountain grasslands located in central Brazil and part of the Cerrado biome (covering 2 million km2) host unique plant communities, currently threatened by quarrying and mining. The grassy matrix of campos rupestres, has long been considered a rich mosaic under the control of local topography and the nature of substrate, but this affirmation has not been well studied. We analyzed whether plant communities varied in relation to edaphic factors within the stony substrate and the sandy substrate of this grassy matrix. We selected 5 sites where occur both grasslands on stony substrate and on sandy substrate, and we carried out vegetation surveys and soil analyses. We counted 222 plant species within our communities, among which 38.6% are exclusively found on campos rupestres. Our results show that both soil-types are strongly acidic, nutrient poor and exhibit a seasonal variation. Phosphorus increases and pH and organic carbon decrease during the dry season. Stony soils are slightly richer in nutrients than sandy soils and differences in soil granulometry and composition have led to the formation of distinct plant communities. Some species are confined to either one or the other grassland-type, which makes the plant composition of each community unique. Variations in edaphic factors generate heterogeneous grasslands favorable to a high plant diversity. Conservation programs and restoration actions have to maintain or recreate this heterogeneity. The presence of distinct plant communities implies that different strategies might be adopted to improve the restoration of these ecosystems. © 2015, Science Press, Institute of Mountain Hazards and Environment, CAS and Springer-Verlag Berlin Heidelberg. [less ▲]

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See detailComparison of translocation methods to conserve metallophyte communities in the Southeastern D.R. Congo
Le Stradic, Soizig ULiege; Seleck, Maxime ULiege; Lebrun, Jean ULiege et al

in Environmental Science and Pollution Research (2015)

In southeastern Democratic Republic of Congo, unique metallophyte communities supporting numerous endemic species occurred on the highly mineralized copper cobalt (Cu–Co) hills throughout the province ... [more ▼]

In southeastern Democratic Republic of Congo, unique metallophyte communities supporting numerous endemic species occurred on the highly mineralized copper cobalt (Cu–Co) hills throughout the province. These hills are economically valuable mineral reserves; mining activities represent therefore a threat to the long-term persistence of these communities. Ex situ conservation program was set up by a mining company to rescue and conserve the diversity of Cu–Co communities until restoration activities are initiated. Two kinds of Cu–Co communities: the steppe and the steppic savanna, were translocated using topsoil spreading and whole-turf translocation. In this study, we assessed the effectiveness of these two techniques in conserving Cu–Co communities and their potential use in future restoration programs. More than 2 years after the translocation, whole-turf translocation appeared to be the better technique for ex situ conservation of endemic Cu–Co species. Not only did whole-turf successfully translocate numerous target species that were not present in the topsoil areas, but it also resulted in fewer ruderal and non-target species compared to topsoil spreading. Topsoil spreading recorded low seedling emergence from seed bank due to large proportions of dormant seeds or the absence of a seed bank, especially for the steppic savanna. Restoration of the steppe is currently more successful than for steppic savanna where the lack of dominant and structuring species likely contributed to divergence in species composition compared to reference ecosystem. Our study stresses the fact that tropical old-growth grasslands, which require probably several centuries to assemble, are difficult to restore or translocate. © 2015 Springer-Verlag Berlin Heidelberg [less ▲]

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See detailImplication of plant-soil relationships for conservation and restoration of copper-cobalt ecosystems
Faucon, M.-P.; Le Stradic, Soizig ULiege; Boisson, Sylvain ULiege et al

in Plant and Soil (2015)

Background: Chemical soil factors play an important role in generating and maintaining plant diversity. Naturally metal-enriched habitats support highly distinctive plant communities consisting of many ... [more ▼]

Background: Chemical soil factors play an important role in generating and maintaining plant diversity. Naturally metal-enriched habitats support highly distinctive plant communities consisting of many rare and endemic species. Species of these plant communities possess remarkable physiological adaptations and are now being considered key elements in the implementation of green technologies aimed at phytoremediation of contaminated soils and post-mined soils. Several studies have emphasised that industrial mineral extraction results in serious damage to ecosystems and serious threats to human health and leads to the extinction of metallophyte species. In the southeastern Democratic Republic of the Congo (DRC), mining activities represent a threat to the long-term persistence of communities located on metalliferous copper and cobalt outcrops and their associated endemic metallophytes, which are currently considered some of the most critically endangered plants in the world. Scope: Plant diversity conservation of metal-rich soils must assess soil-plant relationships at different scales (ecosystems, communities, and populations) to define in-situ and ex-situ conservation and restoration projects. This paper proposes a review of soil-plant relationships involved in plant diversity and endemism and their implications for biodiversity conservation and restoration. © 2015 Springer International Publishing Switzerland [less ▲]

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See detailWhere tree planting and forest expansion are bad for biodiversity and ecosystem services
Veldman, J.W.; Overbeck, G.E.; Negreiros, D. et al

in Bioscience (2015)

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See detailDiversity of germination strategies and seed dormancy in herbaceous species of campo rupestre grasslands
Le Stradic, Soizig ULiege; Silveira, Fernando A. O.; Buisson, Elise et al

in Austral Ecology (2015), 40(5), 537-546

The effects of fire on the vegetation vary across continents. However, in Neotropical fire-prone grasslands, the relationship between fire and seed germination is still poorly understood, while their ... [more ▼]

The effects of fire on the vegetation vary across continents. However, in Neotropical fire-prone grasslands, the relationship between fire and seed germination is still poorly understood, while their regeneration, especially after strong anthropogenic disturbance, is challenging for their conservation. In the present study, we assessed diversity of germination strategies in 15 dominant herbaceous species from Neotropical altitudinal grasslands (locally known as campos rupestres). We exposed seeds to several fire-related treatments. We also compared germination between regularly and post-fire fruiting species. Finally, we investigated the diversity of dormancy classes aiming at better understanding the biogeography and phylogeny of seed dormancy. Germination strategies varied among families. Velloziaceae and Xyridaceae produced non-dormant, fast-germinating seeds. Cyperaceae and Poaceae showed an extremely low or null germination due to a high proportion of unviable or embryo-less seeds. The seeds of campo rupestre grasslands are fire resistant, but there is no evidence that fire triggers germination in this fire-prone ecosystem. Although heat and charred wood did not promote germination, smoke enhanced germination in one grass species and decreased the mean germination time and improved synchrony in Xyridaceae and Velloziaceae. Fire had a positive effect on post-fire regeneration by stimulating fruit set in some Cyperaceae and Poaceae species. These species produced faster germinating seeds with higher germination percentage and synchrony compared to regularly fruiting Cyperaceae and Poaceae species. This strategy of dispersion and regeneration seems to be an alternative to the production of seeds with germination triggered by fire. Physiological dormancy is reported for the first time in several clades of Neotropical plants. Our data help advance the knowledge on the role of fire in the regeneration of Neotropical grasslands. © 2015 Ecological Society of Australia. [less ▲]

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See detailEcology and evolution of plant diversity in the endangered campo rupestre: a neglected conservation priority
Silveira, F. A. O.; Negreiros, D.; Barbosa, N. P. U. et al

in Plant and Soil (2015)

Background: Botanists, ecologists and evolutionary biologists are familiar with the astonishing species richness and endemism of the fynbos of the Cape Floristic Region and the ancient and unique flora of ... [more ▼]

Background: Botanists, ecologists and evolutionary biologists are familiar with the astonishing species richness and endemism of the fynbos of the Cape Floristic Region and the ancient and unique flora of the kwongkan of south-western Australia. These regions represent old climatically-buffered infertile landscapes (OCBILs) that are the basis of a general hypothesis to explain their richness and endemism. However, few ecologists are familiar with the campo rupestre of central and eastern Brazil, an extremely old mountaintop ecosystem that is both a museum of ancient lineages and a cradle of continuing diversification of endemic lineages. Scope: Diversification of some lineages of campo rupestre pre-dates diversification of lowland cerrado, suggesting it may be the most ancient open vegetation in eastern South America. This vegetation comprises more than 5000 plant species, nearly 15 % of Brazil’s plant diversity, in an area corresponding to 0.78 % of its surface. Reviewing empirical data, we scrutinise five predictions of the OCBIL theory, and show that campo rupestre is fully comparable to and remarkably convergent with both fynbos and kwongkan, and fulfills the criteria for a classic OCBIL. Conclusions: The increasing threats to campo rupestre are compromising ecosystem services and we argue for the implementation of more effective conservation and restoration strategies. © 2015 Springer International Publishing Switzerland [less ▲]

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See detailToward and old-growth concept for grasslands, savannas, and woodlands
Veldman, Joseph W; Buisson, Elise; Durigan, Giselda et al

in Frontiers in Ecology and the Environment (2015), 13(3), 154162

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