Impact Of Climate Change On The Phytobiodiversity Of Tazekka National Park

The Tazekka National Park, created in 1950 on an initial area of 680 hectares, located in the mountain range of the Eastern, Middle Atlas, offers a great variety in terms of the landscape and the diversity of forest populations. However, studies have reported that the park’s biodiversity is threatened due to anthropogenic and climatic factors. The aim of this work is to carry out a comparative study concerning the influence of climate change during the years 1985, 2007 and 2018 on the distribution of plant species in different stations of the Tazekka National Park (Ras al ma, Bab Boudir, Bab Azhar and Jbel Tazekka). To carry out this work, several field trips were carried out. The results obtained in the form of GIS using the ArcGis 10.4.1 software have shown that climate change significantly influences the plant biodiversity of the Park. It is necessary to find assessment, monitoring and management strategies for these climate risks in order to preserve phytobiodiversity.


Introduction
Currently, climate change is a reality and our planet's climate is very unstable. Indeed, the impact of climate change is unprecedented and biological responses to these changes are also rapid at the level of ecosystems, communities and species (Heino et al., 2009).
Morocco is one of the most original Mediterranean countries from a geographical, climatic and ecological point of view and, consequently, among the most interesting in terms of its wealth in biodiversity.
Several factors interact to provide a vast floristic diversity in the western Mediterranean basin. In order to protect this national heritage, the Kingdom of Morocco has identified a network of ten national parks including the Tazekka National Park (PNT) located in the mountain range of the Eastern Middle Atlas.
It offers a great variety concerning the landscape and the diversity of forest stands. However, this national park suffers from many obstacles which are obstacles to its development. Indeed, human pressure and climate change are among the most important factors that condition the evolution of this flora, which is seriously threatened with extinction (Jinghua et al., 2014).
In this context, we have studied the effects of climate change on the phytobiodiversity of the PNT and proposed strategies to mitigate the risks associated with these changes.
The analyzes of the Landsat images of the years 1985, 2007 and 2018, carried out by the ArcGis 10.4.1 software, allowed us to highlight the spatio-temporal variations of the plant groups at the level of the Tazekka National Park (PNT).

Geographical Setting
To conduct this study, several field trips were organized in different PNT stations (Ras al ma, Bab Boudir, Bab Azhar and Jbel Tazekka), (Figure 1

General Presentation of the Study Area (PNT)
In the Middle Atlas, particularly in the southwest of the town of Taza, is located the Tazekka National Park (PNT), which now covers 13,737 hectares and which is home to a plant biodiversity very rich in forest formations (Cedar, Oaks, pines...) and the vascular flora.

Climatic Data
The climate is characterized by its climatic elements, in a region determined. Indeed, these climatic elements are measurable (pressure, precipitation, humidity, winds, temperature,...) and which are influenced by local geographical factors: latitude, altitude, continentality, arrangement and characteristic of the relief , vegetation and also the urbanization.
For the various PNT stations, the Emberger rainfall climagram ( Figure 2) shows that the bioclimatic encountered in the study area range from sub-humid to humid with variants ranging from cold to temperate.      (Rouse and al., 1973), it reflects the different reflectances of the vegetation. The result of a NDVI takes the form of a new image, the value of each pixel being between 0 (bare soil) and 1 (maximum vegetation cover), (Hountondji et al., 2004).

Results and Discussions
According to the outings carried out in different PNT stations, the tree stratum includes several species classified into two categories according to their abundance. We distinguish between major forest species and secondary forest species.
Among the major forest species we mention the Atlas cedar (Cedrus atlantica), we also mention the holm oak (Quercus rotundifolia), the cork oak (Quercus suber), comes the zeen oak (Quercus faginea).
Finally, the kermes oak (Quercus coccifera) which is very rare.
While the herbaceous layer in each station of the park is very diverse in plant species which belong to several botanical families.   In the Ras el ma resort we find the presence of holm oak and mixed holm oak accompanied by unwooded land.
At the level of Bab boudir we see that it is the holm oak which dominates with a weak presence of the artificial resinous forests which contain the cedar.
Concerning Jbel Tazekka it is the cedar which dominates with the presence of the zeen oak.
Within the Bab Azhar zone, cork oak dominates with the presence of small spots of coniferous forests.
Currently, vegetation growth and biomass production are monitored regionally using NDVI.
When the normalized vegetation index (NDVI) is between 0 and 1, the vegetation is therefore denser.
Conversely, when the NDVI is between -1 and 0, the vegetation is light and moderately dense.   For Rass al ma: We find that there is a slight disappearance of the coloring but which will be replaced by blue and light red which means that there is a progression accompanied by a vegetative regression.

For Bab Boudir:
It is observed that the red color covers the length of the territory of the zone which means a great regression concerning the vegetation.

For Jbel tazekka:
In this area there is an appearance of the red color which shows a more remarkable vegetative regression.

Bab Azhar:
For this station we note the presence of three colors (red, blue and black).
According to figure 10 (1985 -2018), a very clear difference can be observed at the level of the 4 PNT stations. In fact, in this area we noticed that the blue color appears more and more, which explains the evolution of the vegetation in this region.   At Bab Boudir, we note the presence of white and light blue. Therefore, the white coloring indicates that the vegetation remains stable without any progression and the light blue coloring indicates a weak evolution which affects the flora and which is distributed along the region (presence of arboretum).
In Jbel tazekka station, we notice that there is a dominance of two colors (black and blue). So we almost have a balance between evolution and the absence of vegetation. In addition, we also have a small patch of red coloring which signifies vegetative regression (Holm oak and Zeen oak).
Meanwhile, in the area of Bab Azhar we observe multiple colors (blue, red and black) with dominance of blue and white. Therefore, the vegetation is present along the area with a rather weak evolution (presence of the cork oak).
Therefore, from 1985 until 2007, the vegetative diversity of these stations experienced a more significant regression which is marked by the color red.
From 2007 until 2018 a progressive evolution of the vegetative territory appears in all the stations and which is more remarkable by the blue coloring.
Vegetative regression and progression are due to human activity and climate change (temperature and

precipitation).
Several studies (Bigot et al., 2005;Cecchi et al., 2009;Soro et al., 2013) have shown that the dynamics of land use is closely linked to several factors, whether it be climatic (type of climate, temperature, humidity, etc.), topographical (altitudes, slopes, exposure of the slopes, etc.), the nature of the soil and finally human action.
Therefore, the applications of space techniques using the ArcGis software make it possible to establish maps of land use and its evolution according to different spatial and temporal scales and to issue an early warning in the event of drought based on various indices. spatial as the vegetation index by normalized difference.
All of these results provide proof that plants are migrating with current climate change to maintain the temperatures necessary for their survival. The different migration speeds between trees and herbaceous plants can also increase competition between plant species, and should lead to a change in the composition of plant communities and their relationships with the animal species that interact with them (Lenoir et al., 2008).
Climate change therefore corresponds to long-term modifications of one or more elements of the climate, mainly temperature and precipitation (Stucki et al.,1998).
This therefore leads to a transformation of the environment which results in the disappearance and appearance of certain habitats and, more generally, by the displacement of the geographical area which hosts the habitats necessary for a species.
A Kenyan study has shown that the risks of floods and droughts have the greatest effects on Kenyan society and that the country urgently needs a series of measures to tackle current and future vulnerabilities from climate change (Samwel, 2017).
Other research has already shown that there is a generalized change in the natural calendars (phenology) of plants and animals, as well as changes in the distribution of some species (Lovejoy, 2008). Some tree species may be able to adapt to climate change, allowing trees to survive in many nature reserves, but some cannot (Jinghua et al., 2014). Indeed et al. (2020) showed that climate change may lead to an increase in abundance of one plant species by reducing the abundance of another.
Therefore, for many plants, climate has indirect effects and most studies have generally agreed that variation in environmental factors (including climate change) dominates the deterrent processes for changes in the composition of plant communities (Heino et al., 2010;Mykrä et al., 2007;Victorero & al., 2018). This will increasingly contribute to the disruption of the earth's natural ecosystems and lead to the extinction of plant species.

Conclusion
The main objective of this study was to show the evolution of the climate in the Tazekka   In fact, the results obtained by the ArcGis software have shown that there is really a climate change which influences the plant biodiversity of the Park. Among the effects of this phenomenon, the shift in the range of these species towards the poles and higher altitudes.
Also, many species have adjusted or adapted to the modification of their living conditions. Other species or taxa have not adapted, which has caused their total or partial disappearance in the geographical air of the Park.
Climate change therefore modifies the abiotic factors of the environment in which living organisms evolve: light, temperature, soil and air humidity, chemical composition of water, atmospheric and hydrostatic pressure, physical and chemical structure of the substrate. These changes can have significant impacts on the structure and functioning of ecosystems, by modifying the biology or behavior of organisms (plants, animals, microorganisms).
For that, it is very necessary to develop research in this field and to multiply the efforts in order to propose solutions and new strategies which make it possible to attenuate the factors which accelerate climate change in particular, the use of renewable energies, practice climate-smart agriculture and preserve forests.