1,720,996 research outputs found
Reproductive biology of an Alpic paleo-endemic in a changing climate
No full textClimate change is known to have a profound influence on plant reproduction, mainly because it affects plant/pollinator interactions, sometimes driving plants to extinction. Starting from the Neogene, the European climate was subjected to severe alterations. Nevertheless, several genera, including Berardia, survived these climatic changes. Despite the numerous studies performed about the relationship between climate change and plant reproductive biology, equivalent studies on ancient species are lacking, even though they may furnish crucial information on the strategies that allowed them to survive drastic climatic fluctuations. We investigated floral and reproductive features in Berardia subacaulis (Asteraceae), describing pollen vectors, capitulum and florets phenology, evaluating reproductive efficiency and defining the reproductive mode of the plant with bagging experiments and test of apomixis. B. subacaulis grows in habitats with low pollination services; it is self-compatible, but many typical features favouring cross-pollination are still present: florets are characterized by incomplete protandry, capitulum protogyny and high pollen–ovule ratio. The plant is not apomictic and selffertilization is allowed within each capitulum. Similarly to other European Alpine endemics supposed to belong to the Mediterranean ancient tropical flora, the reproductive mode observed in the monospecific genus Berardia assured reproduction also under a pollinator decline. Differently from the other endemics, it took advantage of its spontaneous self-pollination and compatibility and its generalist pollination service, common both among high altitude plants and in the Asteraceae
Reproductive efficiency of Primula allionii: is this endemic plant really threatened?
No full textPrimula allionii is a primrose endemic to Maritime Alps. The plant was studied
in three different plots representing the different structures of cliffs where the
species usually lives. The reproductive success of the plant was analyzed in
order to evaluate its conservation status. Mean plant dimensions and
distribution within the plots were evaluated. The species resulted low morph
biased (0.13), very fertile (83.53%) and with a quite good sexual organs
efficiency of flowers (both in pin and thrum morphs) as demonstrated by the
high rate of fruit (52.18%) and seed production (20-50% ovules developed in
seeds). However, the populations remain in a demographic balance ( % =
0.38) and very few seedlings (0.21% of available seeds) were recorded in
populations. The particular habitat of the plant does not favour a consistent
population renewal. Primula allionii populations are not under a real threat at
present: but the species and its loci deserve much more consideration in the
future in order to preserve this possibly fragile habitat
Germinazione e propagazione in vitro di due primule endemiche delle alpi sud-occidentali: Primula allionii Loisel. e Primula marginata Curtis
No full textNote sulla germinazione in vitro di Primula allionii Loisel. e Primula marginata Curtis, due specie endemiche delle Alpi Marittime. Il protocollo potrebbe essere di grande utilità per operazioni di conservazione ex situ e interventi di conservazione in situ
Pollination strategies in the narrow endemic species Primula allionii Loisel. (Primulaceae).
No full textPrimula allionii Loisel. is a primrose endemic to Maritime Alps. Flower and pollen features related to pollination mechanism were analyzed, and the seasonal presence of insects visiting the plant was monitored
Knowing the past to forecast the future: a case study on a relictual, endemic species of the SW Alps, Berardia subacaulis
No full textFuture climate change may lead to a substantial loss of biodiversity, particularly affecting mountain regions, including the Alps. Range-size reduction in high mountain plant species is predicted to be more pronounced for endemic species. Investigating the broad temporal spectrum of range shifts is important for the conservation of biodiversity, since learning how species responded to climate change in the past provides useful insights on how they might react to warming trends in the present and future. Using species distribution models and an ensemble forecasting approach, we explored how the distribution of Berardia subacaulis, a monospecific genus endemic of the south-west Alps, may be affected by past and future projected climate change. During the last interglacial, the habitat suitability of Berardia was lower than present and a progressive increase was observed from the last glacial maximum until now. In the future, Berardia appears to lose more than 80 % of its range, becoming endangered by 2050. Our results suggest that Berardia probably survived past warmer periods in situ, expanding its distributional range during cooler periods. The severe future range contraction predicted for Berardia reflects similar results for other endemic species. As Berardia represents an interesting model species to evaluate the effects of climate warming on range size and shifts, demographic and precise range monitoring may be undertaken on this species
Ex situ conservation of Ligurian endangered species
No full textThe main objectives of the Ligurian Germplasm Bank are to conserve and to study endemic, rare, threatened and policy species from Liguria Region. In order to achieve these goals, we collected and stored accessions representative of morphological and genetic diversity of the studied taxa
Indagini sulla capacità germinativa in subpopolazioni liguri di Brassica montana Pourr. (Brassicaceae).
No full textCinque lotti di semi di Brassica montana provenienti da quattro località diverse della Liguria, sottoposte a condizioni di stoccaggio differenti, sono stati sottoposti a test di germinazione e hanno mostrato differenze significative
Assessing the Effect of Climate Change in Vascular Plants with Disjunct Populations
No full textMany species exhibit intraspecific ecological variation, and to not consider this ecological differentiation can confound predictions made with species distribution models (SDMs). This problem may be particularly relevant for species where there are few populations with potential local adaptations. To increase the performance of niche models and provide more solid basis for conservation plans, it is recommended to apply a subdivision criterion with biological significance. In this study, we examined twelve species with disjunct populations and created models of both the entire species and each group of populations. In addition, we considered as an “aggregate model” for the species the area predicted to be suitable by at least one of each group of populations. In general, the highest range of contractions were identified by the species model. The species model forecasted a similar trend as the aggregate model in the majority of species, but in four cases they predicted opposite trends. In summary, our results suggest that the inclusion of intraspecific variability does not significantly improve the overall accuracy of SDMs based on all species occurrences, but may lead to substantially different conclusions about future range changes. Furthermore, they suggest that intraspecific variability alone may provide a buffer against environmental change, even if the niche is conserved among different intraspecific groups. Consideration of intraspecific differences may ultimately allow us to highlight potential resilience units that can act as potential buffers against the adverse effects of climate change, and to develop targeted conservation strategies accordingly
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No full textClimate change is dramatically threatening biodiversity. Narrowly distributed species are especially exposed to extinction risk due to their narrow ecological niche. We used Species Distribution Models at fine spatial resolution (50 m) to investigate changes in the distribution of three range-restricted species of Santolina (Asteraceae) endemic to the Mediterranean Basin (S. decumbens, S. ligustica, S. pinnata). We assessed the future potential range under an optimistic and a pessimistic scenario, and analysed distribution change taking into account three different areas: the distributional range (calculated as convex hull), an area 5 km larger than the distributional range, and a buffer (1 km) around occurrences. Santolina ligustica is expected to dramatically reduce its range under both scenarios, S. decumbens is expected to increase its range under both scenarios and S. pinnata is expected to dramatically reduce its range under pessimistic scenario and to increase it under optimistic one. Moreover, under the optimistic scenario, S. ligustica and S. pinnata show a very high range loss in all areas but the range gain is major in the largest area than in the other two
areas. This result suggests that, in the future, suitable areas will occur mainly outside of the current distributional range and that assisted colonization might be necessary to assure species survival. Differently the third species has a lower range loss and higher range gain within the distributional range and in the buffer around occurrences, suggesting the possibility of survival in microrefugia
within its distributional range despite a wide reduction in suitable habitat. These results might help to design strategies for species conservation in face of future climate change
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