Phytodiversity distribution in relation to altitudinal gradient in Salma Mountains – Saudi Arabia

Changes in species diversity along the ephemeral streams in eastern Mediterranean Mountainous Ecosystem, a case study for Ahir Mountain (Kahramanmaraş-Türkiye)

Ephemeral streams are important habitats that support biodiversity, especially in mountainous ecosystems in arid and semi-arid regions, and are among those that will be most affected by global climate change. This study aimed to examine the trends in plant species diversity of ephemeral stream beds and their relationship with environmental variables (aspect, elevation, soil) in the eastern Mediterranean region.For this purpose, 40 sample plots were applied in the valley cross sections of the ephemeral stream beds (valley bottom, side and ridge) on two main slopes (north and south) in 2019. The abundance values of plant species were determined and the number of individuals in each sample plot was counted. In addition, soil samples were taken at a depth of 0-30 cm and analyzed. With the data obtained, the importance value index of all species was calculated, and the diversity and species richness of the sample plots were determined.A total of 130 plant taxa were identified in the study area. The most dominant species were Astragalus kurdicus (IVI value: 25.97), Helichrysum plicatum (21.94), Taeniatherum caput-medusae subsp. crinitum (15.51), Hordeum bulbosum (15.33), Bromus erectus (15.32), and Minuartia juniperina (14.14). Both plant richness and endemism rate showed a significant relationship with increasing elevation. Plant diversity values of south-facing slopes were higher (2.23) than those of north-facing slopes (2.21). In addition, we found that phosphorus is an important factor in the distribution of plant species along the ephemeral stream beds, and as the amount of phosphorus increases, species richness and diversity also increase.

Impact of Human Settlements on Diversity of Range Vegetation

The rapidly increasing population of human beings in semi-arid areas is often considered as a major factor of land degradation. Only a few studies have examined the dynamics of human settlements on the composition, diversity, structure and palatability of range vegetation in Southern Punjab Pakistan. The current study aims to assess whether the distance from settlements had any effect on the range vegetation’s diversity and cover. In order to determine the impact of human settlements on the vegetation, the sampling area (Thal rangeland) was classified into three categories, i.e., Near (1–2 km from human communities), Away (2–4 km from human communities), and Far (4–6 km from human settlements). A total of 75 transects in all of the three sites were placed in the study sites. Along the transects, a quadrate of 1 m2 after every 10 m was randomly placed. The study site yielded floral diversity of a total of 29 species, representing 23 genera and belonging to 9 families. Results showed that the areas away from the human communities had higher species diversity (20), while the site near to human settlements depicted lower diversity (14). It was observed that, although the site near to communities had lower diversity, it depicted higher plant density, while the highest diversity along with the lowest plant density was observed in sites away from the communities. The study concluded that the diversity of range grasses, especially desirable species, was affected by distance to human settlements. These findings could be useful to detect flora changes, establish habitat protection priorities and improve efforts for conserving natural landscapes.