MAIN PHYTOGENETIC RESOURCES OF SAUDI ARABIA AND THE MAIN THREATS
The varied biodiversity of Saudi Arabia stems from its central location between Africa and Eurasia, leading to a combination of elements from both regions. There are 2,250 flowering species in Saudi Arabia, 246 of which are considered endemic to the region. About 450 species (18%) are directly beneficial for human beings, 45 species (1.8%) are poisonous, and 334 species (13.4%) are used in popular medicine or are known to have medicinal uses.
About 2.7 million hectares of woodland remain in the mountains of Saudi Arabia, especially in remote, steep, inaccessible areas. The juniper (Juniper spp.) forests are one of the few dense forest habits of Saudi Arabia and are concentrated along a narrow strip about 7,600 kilometres long. These forests prosper at 2,000 – 3,000 metres, and are characterised by high diversity of species and biomass. Olives (Olea europaea L.) are starting to appear amongst the junipers on slopes at about 1,500 – 2,000 metres. In addition to mountain forests, there are woods in arid zones featuring acacias in the desert and mangroves along the coasts. The country’s main forest species are Juniperus procera, Olea europaea, Barbeya cleoides, Nuxia oppositifolia, N. congesta, Tarchonanthus comphoratus, Celtis africana, Breonadia salicina, Acacia origena, Teclea nobilis, Ficus vasta, Ficus ingens and Ficus sycomorus.
Some of the main threats to plant diversity are habitat destruction and fragmentation, excessive grazing, excessive hunting, changing intensity in modern farming, chemical pollution caused by improper use of pesticides, increasing recreational activities associated with green areas, the expansion of urban areas and exotic and invasive species. Factors limiting the expansion of forests include insufficient rainfall, the high cost of reforestation and a shortage of sufficiently-qualified forestry workers in Saudi Arabia.
STATUS OF IN-SITU AND EX-SITU CONSERVATION
To date there is documentation on 15 protected areas, covering almost 4% of the surface of all the large physiographical regions and including half the country’s biotopes, the main wetlands, marine and mountain habitats and providing protection for populations of endemic species, species at risk of extinction and in general for the main plant and animal species. Saudi Arabia has drawn up a National Plan for Protected Areas with the aim of covering about 10% of the country. Amongst the most significant of the protected areas are the Asir National Park, the country’s largest, with a total surface area of 450,000 ha and great biodiversity (with herbaceous plants, lichens, junipers, etc.), the Sa’ad National Park, a recreational park covering 300 ha with almost 40,000 trees of different species, and the Al Ahsa National Park, whose main function is to shield farming lands and urban districts from the encroaching sand.
Saudi Arabia gives priority to botanic gardens as a tool for conserving biodiversity ex-situ. It considers them of vital importance for conserving terrestrial and marine ecosystems. The main botanic garden in Saudi Arabia is at the King Saud University in Riyadh, which is run by the Department of Botany and Microbiology of Riyadh University.
The existing germplasm banks are insufficient according to the Saudi Arabian National Strategy for the Conservation of Biodiversity, but essential work is being done by the Germplasm Bank and National Herbarium of the Ministry of Agriculture and Water.
In addition, while searching for information for this study, data was found on the Madinat Yaubu Al-SInaiyah Botanic Garden and on the King Khalid National Wildlife Research Centre (KKWRC). However, according to the National Strategy for the Conservation of Biodiversity, more botanic gardens should be set up around the main towns in Saudi Arabia.