18 research outputs found
Chorological and conservation status of the endemic cypress, Cupressus atlantica Gaussen, in the High Atlas (Morocco)
18 p. ; tablas, mapas, gráf.We present a study of the distribution, ecology and conservation status of Cupressus atlantica, an endemic tree of the High Atlas (Morocco). The main populations of this species grow in a reduced area along the N’Fiss valley in the Central High Atlas and are gradually receding. Particular populations are increasingly fragmented and the total area covered by the cypress woodland has decreased to less than a third of the surface occupied in the 1930s. Overgrazing reduces the woodlands’ regenerative capacity, and the exploitation of the wood, linked to traditional uses by the rural society of the N’Fiss valley, directly reduces the number of trees. Great efforts being made to protect the species by the Haut Commissariat aux Eaux et Forêts are having some effect in recent years.This research was partially funded by the cooperation between the Spanish Research Council (CSIC) and the Polish Academy of Sciences (PAS).Peer reviewe
Consequence of habitat specificity: a rising risk of habitat loss for endemic and sub-endemic woody species under climate change in the Hyrcanian ecoregion
Endemic species are more impacted by climate change than other taxa. However, assessing the vulnerability of endemics to these changes in some regions, such as the Hyrcanian forest, is limited, despite its importance for biodiversity and ecosystem function. To address the question of expected habitat shifts under climate change across the Hyrcanian ecoregion, we built an ensemble of species distribution models (SDM) under two emission scenarios (RCP 4.5 and RCP 8.5) for 15 endemic woody taxa. To identify the potential priority conservation areas, we also applied a spatial prioritization approach. Overall, our results suggest that the impacts of climate change are more severe on the eastern parts of the region (Golestan) and the Talysh Mountains (north-western Hyrcanian ecoregion) with over 85% and 34% loss of suitable habitats over the next 80 years. The central part of the Alborz Mountains (Mazandaran) and some areas in the Talysh Mountains could be potential climatic refugia under the future conditions for endemic taxa. The most prominent changes are expected for Ruscus hyrcanus, Gleditsia capsica, Acer velutinum, Frangula grandifolia, and Buxus hyrcana. The worrying predicted loss of suitable habitats for most studied taxa would dramatically affect the stability and resilience of forests, threatening thus biodiversity of the Hyrcanian ecoregion. We present the first estimation of the potential risks involved and provide useful support for regional climate-adaptation strategy, indicating potential conservation priority areas for maintaining and preserving its resources. Notably, only 13.4% of areas designated for conservation and management under climate change will be located within the current Hyrcanian protected areas, yet the majority of these areas are classified as low priority
Past climatic refugia and landscape resistance explain spatial genetic structure in Oriental beech in the South Caucasus.
Predicting species-level effects of climatic changes requires unraveling the factors affecting the spatial genetic composition. However, disentangling the relative contribution of historical and contemporary drivers is challenging. By applying landscape genetics and species distribution modeling, we investigated processes that shaped the neutral genetic structure of Oriental beech (Fagus orientalis), aiming to assess the potential risks involved due to possible future distribution changes in the species. Using nuclear microsatellites, we analyze 32 natural populations from the Georgia and Azerbaijan (South Caucasus). We found that the species colonization history is the most important driver of the genetic pattern. The detected west-east gradient of genetic differentiation corresponds strictly to the Colchis and Hyrcanian glacial refugia. A significant signal of associations to environmental variables suggests that the distinct genetic composition of the Azerbaijan and Hyrcanian stands might also be structured by the local climate. Oriental beech retains an overall high diversity; however, in the context of projected habitat loss, its genetic resources might be greatly impoverished. The most affected are the Azerbaijan and Hyrcanian populations, for which the detected genetic impoverishment may enhance their vulnerability to environmental change. Given the adaptive potential of range-edge populations, the loss of these populations may ultimately affect the specie's adaptation, and thus the stability and resilience of forest ecosystems in the Caucasus ecoregion. Our study is the first approximation of the potential risks involved, inducing far-reaching conclusions about the need of maintaining the genetic resources of Oriental beech for a species' capacity to cope with environmental change
Morphological diversity and structure of West Mediterranean Abies species
9 p.The aim of this study was the biometrical comparison of Abies pinsapo Boiss., Abies maroccana Trab. and Abies tazaotana Côzar ex Villar from Spain and Morocco. The morphological and anatomical analysis of the needle characters of these firs revealed significant taxonomic differences. The results showed considerable distances between regions and very small differences among the Moroccan fir taxa. The examination of the needles and earlier genetic analysis did not provide evidence for distinguishing A. tazaotana at the species levelPeer reviewe
Genetic diversity and inter-specific relations of western Mediterranean relic Abies taxa as compared to the Iberian A. alba
8 p., fot., mapas, tablas -- Post-print del artículo publicado en Flora - Morphology, Distribution, Functional Ecology of Plants. Versión revisada y corregida.Several Abies species are currently present in the Mediterranean region and most of them are endemic taxa and tertiary relicts. Using six nuclear microsatellites, we studied the genetic structure and inter-specific relationships among West Mediterranean firs, A. pinsapo (Spain), A. maroccana and A. tazaotana (Morocco). Based on the hypothesis that A. pinsapo could historically exchange genes with A. alba growing in the Pyrenees via secondary contact, we investigated the level of genetic admixture between these species using a Bayesian approach. The studied populations showed moderate genetic diversity (mean HE = 0.598) and a high level of genetic differentiation (FST = 0.225) that was especially pronounced between A. alba and the African firs. All populations experienced a strong bottleneck effect that was likely induced by climatic changes occurring in the West Mediterranean during the last glacial cycle and the Holocene. According to Bayesian clustering, both African taxa grouped together in a single cluster, the two A. pinsapo populations formed a second cluster, and two additional clusters were detected within A. alba. Our results indicate that A. tazaotana is genetically very close to A. maroccana, and hence these two taxa should probably not be considered as separate species. We found no genetic admixture between A. pinsapo and A. alba and only minor between A. pinsapo and the African fir populations suggesting an isolation effect of the Gibraltar Strait. Current limited distributions of firs in the Mediterranean region together with changing climate may lead to further deterioration of the genetic diversity levels. Hence, future efforts should focus on monitoring the demography and genetic threats to existing populations.This research was financed by Ministry of Science and Higher Education in Poland(grant
NN303412136)and Institute of Dendrology, Polish Academy of Sciences.Peer reviewe
Genetic Consequences of Hybridization in Relict Isolated Trees Pinus sylvestris and the Pinus mugo Complex
Scots pine (Pinus sylvestris L.) and the taxa from the P. mugo complex can hybridize in the contact zones and produce fertile hybrids. A unique example of an early Holocene relict population of P. sylvestris and P. uliginosa (a taxon from the P. mugo complex) growing on the tops of Jurassic sandstone rocks is located in Błędne Skały (Sudetes). Phenotypically, there are trees resembling P. sylvestris, P. uliginosa and intermediate forms between them. We expected that some of P. sylvestris and/or P. uliginosa-like trees could be in fact cryptic hybrids resembling one of the parental phenotypes. To address this question, we examined randomly sampled individuals, using a set of plastid (cpDNA), nuclear (nDNA) and mitochondrial (mtDNA) markers as well as biometric characteristics of needles and cones. The results were compared to the same measurements of allopatric reference populations of the P. sylvestris and the P. mugo complex (Pinus mugo s.s, P. uncinata and P. uliginosa). We detected cpDNA barcodes of the P. mugo complex in most individuals with the P. sylvestris phenotype, while we did not detect cpDNA diagnostic of P. sylvestris within P. uliginosa-like trees. These results indicate the presence of cryptic hybrids of the P. sylvestris phenotype. We found only three typical P. sylvestris individuals that were clustered with the species reference populations based on needle and cone characteristics. Most trees showed intermediate characteristics between P. sylvestris and P. uliginosa-like trees, indicating intensive and probably long-lasting hybridization of the taxa at this area and subsequent gene erosion of parental species
Niche modelling suggests low feasibility of assisted gene flow for a Neogene relict tree, Castanea sativa Mill.
Taxonomic position of Abies equi-trojani on the basis of needle characters by comparison with different fir species
12 p., 3 tablas, 2 figurasThe needles from 25 trees of Abies equi-trojani from Kazdağı (Mount Ida) were compared with those from four populations of A. alba, two of A. cephalonica, and three of each of A. ×borisii-regis, A. bornmuelleriana, and A. nordmanniana, each represented by 29–31 individuals. Thirty-nine morphological and anatomical needle characters (26 main and 13 estimated ones) were examined biometrically to verify the systematic position of A. equi-trojani. To evaluate the relationships among taxa, Student’s t-test for independent samples,
the Mann–Whitney U test, and discrimination and clustering analyses were applied. The differences between taxa were statistically significant for several characters, but the data ranges generally overlapped between species. Morphological and anatomical characters of the needle allowed to distinguish between A. equi-trojani, A. alba, A. cephalonica, A. ×borisii-regis, A. bornmuelleriana, and A. nordmanniana when used together, but no single character applied separately could distinguish between species. A close relationship of A. equi-trojani to A. bornmuelleriana and to A. nordmanniana detected based on the needle characters supported the infraspecific systematic position of these three taxa.This study was supported financially by the National Science Centre (NCN) of Poland (No. N303 412136) and by the Institute of Dendrology in Kórnik (Polish Academy
of Sciences).Peer reviewe