Assessment of the vulnerability and adaptation to climate change in the Lebanon: Impact on natural areas and wildlife in Lebanon.
This study represents a part of a general study conducted to assess the vulnerability of various Lebanese sectors to the projected global climate changes and the adaptations to the impacts. These sectors include, water resources, marine and coastal resources, agricultural sectors, natural areas, protected areas and wildlife and the overall socioeconomic impacts. The team to conduct this assessment, lead by Dr. M. Khawli, Director of the Lebanese Remote Sensing Center, was assigned by the Lebanese Council for Scientific Research, funded by the UNDP and supervised by the Ministry of the Environment. A colleague, Dr. Samir Safi, and myself concentrated on the aspects summarized below.
TERRESTRIAL ECOSYSTEMS, NATURAL HABITATS AND WILDLIFE
CLIMATE CHANGE VULNERABILITY IMPACT ASSESSEMENT:
The main baseline disturbances that are currently affecting natural habitats are:
a. Chaotic urbanization at the expense of forests and woodlands.
b. Pollution of various sources, air, water and soil.
c. Fires that seem to be increasing in frequency with the lengthening of the dry season.
d. Changes in the water table due to excessive water exploitation for domestic and agricultural use.
e. Quarrying activity which is also affecting the water table.
g. Fragmentation by one or more of the above factors.
Any intensive or extensive increase in any of these factors will lead to a degradation of the natural habitats that will be further exasperated by climatic changes.
1. The expected changes in the distribution of vegetation communities may lead to the disappearance of certain vegetation associations and their replacement by others. For example, a forest may regress into a shrubland or even grassland depending on the intensity of the modification.
Two forests in protected areas, namely Horj Ehden in the North and Arz Al-Shouf in the Barouk Mountain are characterized by great floral diversity of herbaceous and arborescent plants containing many endemic, rare and endangered species some of which are at the southernmost edge of their distribution. Climatic factors are not the only factors that may affect the success of cedars but there is a clear preference for humid atmospheres and moist well-drained soil.
According to the climatic scenario used here, there may be a 300m upward shift in the year 2020, 486m in 2050 and more than 700 meters in the year 2080. This would push the tree line in the year 2080 in both reserves to around 2500m. Considerable stress will begin to be felt as early as the year 2020. This makes both protected areas highly vulnerable. Furthermore, the rate of change may be faster than the species ability to adapt. Montane vegetation as found in the two above-mentioned reserves may face considerable threat of serious decline and even disappearance.
Other factors, however, such as the increased water efficiency due to CO2 increase may enhance its ability to withstand the new drought conditions. It is also uncertain to what extent and how soon there may be a change in soil characteristics affecting the vegetation.
In the main wetland area in Lebanon, the Ammiq ephemeral marshes intensive water pumping for the irrigation of several cultivated lands in the surrounding areas has reduced the area and shortened its seasonal span. It is expected that, in the absence of climate change and due to the lack of management plans, these marshes will be affected by:
Change in land use in the surrounding areas, where more land will be reclaimed for cultivation,
Increased water demand for the irrigation of these and other nearby cultivated lands.
The effect of climate change on the marshes may take two forms:
1. Spatial: leading to reduction in the total area of the marshes
2. Temporal: shortening of the duration in which the marshes exist during each year. This may mean, for example, that there may be no marshland left for the birds in their autumn return migration.
It is estimated that the total area of the marshes may undergo a decline at the rate of about 6% per year. At this rate, without climate change, the marshes may practically disappear in less than two decades and without climate change. This will be obviously exasperated under climate change.
The Sour sandy beach, the only remaining significant sand dune habitat in Lebanon for many plants and animals that are unable to thrive except on sandy substrates. The main pressures on the sandy beach in the foreseeable future, without climate change, is land reclamation and tourist development. Increased population density and the demand for more agricultural land will place more pressure on the whole zone. It is considered to be highly vulnerable to sea level rise and is classified as “critical”. This implies high vulnerability to erosion and flooding. The establishment of a nature reserve in the Ras El-Ain area may not be enough to protect sufficient sandy areas. There is a risk that the sandy beach narrow or even disappear with its indigenous fauna and flora.
The Palm Islands Nature Reserve, composed of three islets, will be subjected to inundation under a climate-change scenario.
The main problems facing the Lebanese wildlife today are the same as those listed above for natural areas. Populations of many species may be subjected to extirpation (local extinction) due to the great fragmentation affecting their habitats. This fragmentation is likely to continue and perhaps accelerate due to increased urbanization.
The species most vulnerable to climate change may be those that are endemic, endangered, at the edge of their geographic distribution, montane, coastal and those which may be replaced by potential competitors from other zones. Some such species have been named in this report as facing decline or extinction.
In Lebanon, the known endangered forest tree species are found in degraded, heavily grazed areas. The extent to which they face threat is directly related to the continuing human pressures through felling and grazing. No study has quantified these two aspects. Under climate change, some their areas of distribution may shift bioclimatically putting more stresses on these species.
Adaptations that may reduce the climate change impact may include the following:
1. Natural adaptation where the vegetation and wildlife may acclimatize where the climate change may srtill be within their tolerance range. Some may adapt (in the evolutionary sense) if containing enough genetic diversity. T
2. Natural adaptation may have to be assisted by exploring and cultivating certain drought-tolerant ecotypes. It may be also be enhanced by reducing habitat fragmentation and thus allowing the natural genetic variation to lead to suitable adaptations.
3. Habitat fragmentation can be reduced by establishing corridors and connections between the isolated habitat types.
4. Intensive studies on species and ecosystems have to be devoted to assess the degree of vulnerability an to discern the above aspects.
5. Water use and change in land use have to be rationalized to protect wetlands and riparian habitats.
6. The area and the number of protected areas need to be expanded to include more of the sensitive habitat types and/or more vegetation and bioclimatic zones.
7. Buffer zones need to be established around protected areas to reduce the human impacts and those of climate change.
8. Adaptation measures have to be adopted within the next two decades.
9. Because of the international importance of some protected area it may be possible to seek international assistance especially in schemes such as “debt swapping” which involves trading foreign debts for financing the establishment and maintenance of protected areas and nature reserves.