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CURATOR
A pinboard by
dina alsharkawy

researcher, suez canal university

PINBOARD SUMMARY

Conservation of threatened plant species against climatic changes and human interference.

In the recent years, it had been noticed that many plant species in the Egyptian flora are endangered due to the severe impact of the human activities on the natural vegetation. The continuous over-grazing, over-cutting and up-rooting resulted in disappearance of pastoral plant communities and paucity of trees and shrubs as well as disappearance of many rare and endemic plant species. This misuse and depletion of natural resources caused environmental degradation and gene loss or erosion. In fact this mismanagement of natural resources threatens human kind that the majority of the world's people depend on plants for their livelihood since they grow them for food, fuel, timber, fodder and many other uses. Sustainable advances in biological productivity will not be possible without access to biological diversity. Some climatic models predict that aridity will increase in several areas of the world during the 21st century in association with global warming. Hence, improving our knowledge of the species distribution of extremely arid environments plants is a matter of utmost importance to better understand and predict patterns of vegetation change in areas likely to be affected by increasing aridity in the coming decades. Although the relationship between climate and species ranges is well established, as is the relationship between climate change and species range shifts based on paleoecological studies,using SDMs to predict the impact of global warming on species distributions requires a number of assumptions. It must be assumed that species distributions tend to be in equilibrium with the climate and this assumption does not account for time lags.

3 ITEMS PINNED

Endemics and their common congener plant species on an East Mediterranean island: a comparative functional trait approach

Abstract: Abstract Understanding evolution and ecology of endemic plants is of great importance for conservation of those rare and endangered species. Pairwise comparisons of plant functional traits could be an adequate method to get insights in evolutionary and ecological processes. We examined whether morphological traits representing competitive ability and habitat specificity differ between endemics and common plants. Therefore, we performed pairwise comparison analyses of 9 plant functional traits in 36 congeneric pairs of endemics and their common congeners on the East Mediterranean island of Cyprus, i.e., the first such study conducted on a Mediterranean island. We found that endemic species prefer higher elevations and more extreme habitats. Endemics were smaller and they had smaller flowers than their common congeners. Common species had higher chromosome numbers than endemic ones. Endemic and common species showed no significant differences in canopy height, inflorescence height, leaf length and width, and flowering period. Our study showed that the situation on a large oceanic island does not differ from results in mainland research areas.AbstractUnderstanding evolution and ecology of endemic plants is of great importance for conservation of those rare and endangered species. Pairwise comparisons of plant functional traits could be an adequate method to get insights in evolutionary and ecological processes. We examined whether morphological traits representing competitive ability and habitat specificity differ between endemics and common plants. Therefore, we performed pairwise comparison analyses of 9 plant functional traits in 36 congeneric pairs of endemics and their common congeners on the East Mediterranean island of Cyprus, i.e., the first such study conducted on a Mediterranean island. We found that endemic species prefer higher elevations and more extreme habitats. Endemics were smaller and they had smaller flowers than their common congeners. Common species had higher chromosome numbers than endemic ones. Endemic and common species showed no significant differences in canopy height, inflorescence height, leaf length and width, and flowering period. Our study showed that the situation on a large oceanic island does not differ from results in mainland research areas.

Pub.: 09 Nov '16, Pinned: 26 Sep '17

Predicting the global incidence of seed desiccation sensitivity

Abstract: The ability of seeds to tolerate desiccation plays an important role in plant regeneration ecology. Globally, the majority of species produce desiccation-tolerant (orthodox) seeds, while comparatively few produce desiccation-sensitive (recalcitrant) seeds that are unable to survive dehydration. The trait has important implications for species conservation, as desiccation-sensitive species cannot be conserved using traditional seed banking techniques. In addition, these species may be less resilient to the increases in droughts predicted for some regions under climate change scenarios.The best available resource on seed desiccation tolerance is the Royal Botanic Gardens, Kew's Seed Information Database. This database contains seed desiccation-sensitivity data for over 18 000 taxa, approximately 3% of which have desiccation-sensitive seeds. However, this database is likely biased towards desiccation-tolerant species. Previous attempts to estimate the proportion of seed plants with desiccation-sensitive seeds have ranged from 7% to 50%. Here, we aimed to overcome sampling bias to derive a best estimate for the proportion of seed plants with desiccation-sensitive seeds, based on current data.We used a recently developed method, based on taxonomic relatedness, to account for sampling bias and estimate the proportion of seed plants with desiccation-sensitive seeds. As a comparison, given that seed desiccation sensitivity is strongly related to habitat, we repeated our analyses using habitat as a basis.The predictions from our taxonomy-based models ranged between estimates of 7·5% and 19·6% of the world's seed-plant species with desiccation-sensitive seeds, depending on model type, while the habitat-based models suggested a value of approximately 8%. Our evidence suggests that, based on current data, the best estimate of the proportion of species with desiccation-sensitive seeds is likely to be approximately 8%. Tropical and subtropical moist broadleaf forests had the highest incidence of seed desiccation sensitivity, where an estimated 18·5% of the seed-plant flora possessed the trait.Synthesis. Alongside our estimation of the numbers of species with desiccation-sensitive seeds, we provide data on taxa and habitats where this trait may be most prevalent. These findings can be used to support conservation planning, particularly with respect to providing decision support for in and ex situ conservation techniques.

Pub.: 30 Jan '17, Pinned: 26 Sep '17