Analysis of the Diversity of Spontaneous Urban Flora – The Case of Temara City, Morocco

Spontaneous flora offers many functions and potentialities in the urban ecosystem. However, few studies have been carried out on this subject in Morocco. The present study aimed to analyze the diversity of spontaneous flora in the urban area of Temara, to contribute to interpreting the structure and dynamics of Moroccan spontaneous flora. During the study, 90 floristic surveys were carried out along four transects, marked A, B, C, and D so that each transect started from the city center and went in one of the four directions of the study area. Transect A ran northwards from the city center, transect B westwards, transect C southwards, and transect D eastwards from the city center. To carry out the floristic surveys, several survey areas were chosen, given the heterogeneity of the urban environment. These areas ranged from a few cm 2 for rock fissure plants, through 10 to 25 m 2 for grasslands, to 25 to 100 m 2 for forest cuttings. The results revealed a total of 137 taxa grouped in 116 genera and belong to 33 floristic families. The Asteraceae family came out on top, with 30 species (21.90%) and 24 genera, and the Poaceae family was in second place with 21 species (15.33%) divided into 20 genera. Analysis of this floristic list indicates a predominance of the therophyte life form (48.90%), then hemicryptophytes (26.28%) followed by geo - phytes (10.22%) in terms of biological type, and a predominance of the Mediterranean element (31.19%) in terms of chorological type. Of the 137 taxa inventoried, 10 are very rare, 1 is rare, 1 has a doubtful presence, and 2 are endemics. This study showed that even in a disturbed and fragmented environment, such as the urban environment, certain spontaneous plant species adapt to the conditions prevailing in this habitat and show considerable diversity, thus contributing to a better interpretation of the composition and dynamics of the country’s flora.


INTRODUCTION
The urban ecosystem is the result of accelerated urbanization, highly correlated with the loss and degradation of natural habitats, population growth, and intense human activities (Gross, 2019), leading to a loss of biodiversity in the urban environment (Malkinson et al., 2018).Furthermore, by creating new habitats with different characteristics, the urban environment contributes to promoting biodiversity (Qian et al., 2020).In the urban ecosystem, most of the flora is in the form of cultivated plants.However, there is also a significant proportion of flora that has not been cultivated by humans, known as spontaneous flora, which has managed, with its own resources, to tolerate the conditions of different urban habitats (Forman, 2014).In the urban ecosystem, spontaneous plants form new communities, thus creating new axes and opportunities for evaluating as well as studying the effect of anthropogenic activities on plant associations and related ecosystem services, as these studies will provide important aspects for better understanding the strategies with which plants respond to the conditions prevailing in urban environments and how these plants contribute to the characteristics of urban ecosystems (Hu et al., 2021).Studies on spontaneous flora in the urban environment of Morocco are very limited.In order to contribute to the interpretation of the structure and dynamics of Moroccan spontaneous flora, this study proposes to inventory and analyze the diversity of spontaneous flora in the city of Temara.

Study area
The Temara region (Figure 1), located southwest of Rabat and northwest of Morocco (33° 55' 13.177" N 6° 55' 38.629" W), is a coastal area along the Atlantic Ocean that forms part of the north-western coastal meseta (Chahid et al, 2012).Considering its north-western geographical location, the Temara area is part of the semiarid and sub-humid bioclimate.The climate in this area is Mediterranean, with dry summers and mild, wet winters.The Atlantic Ocean has a buffering effect on nearby regions, including Temara, through the humidity it brings to the continent (Stoetzel and al., 2014).Annual precipitation averages 555 mm, and average temperatures are generally mild, with no recorded extremes (Taazzouzte et al., 2021).

Sampling method
To inventory and examine as much of the spontaneous flora of the Temara urban area as possible, the authors opted for McDonnell's (1990) urban-rural transect method, in the form of 4 perpendicular transects, labeled A, B, C, and D, so that line A started from the city center towards the north of the city, line B from the city center towards the west, line C from the city center towards the south and line D from the city center towards the east of the city.
A series of field surveys were conducted during the period from May to June 2023, enabling to compile a list of species of spontaneous flora in the study area.To carry out the floristic surveys, the Braun-Blanquet method was adopted (Meddour, 2011), and a dominance-abundance index was obtained for each species studied.Considering the high level of disturbance in the urban environment, spontaneous vegetation is spatially more or less extensive.For this reason, the survey areas were adopted as proposed by (Gorenflot &

Data analysis
Species identification was made concerning the following floras: The catalog of Moroccan plants (Jahandiez & Maire, 1931-1932-1934, Emberger & Maire, 1941), consulted at the scientific institute in Rabat, Morocco, and The synonymic index of the flora of North Africa (Dobignard &Chatelain, 2010 and2011).It was completed by nomenclature checks on the databases of the Tela-Botanica website (tela-botanica.org).It should be mentioned that a preliminary identification of species was carried out in the field, using the "Pl@ntNet" mobile application (Version 3.11.2) developed by Tela-Botanica, and subsequently verified by consulting the Floras cited above.The rarity and endemism statuses of the taxa are determined based on those adopted by (Fennane & Ibn Tattou, 1998).Taxon threat categories are defined concerning Elements for a Red Book of the vascular flora of Morocco (Fennane, 2017(Fennane, & 2018)).The phytogeographical distribution of the species identified in this study was established based on The New Flora of Algeria and southern desert regions (Quézel & Santa, 1962, 1963).

Systematic aspect
The floristic surveys carried out as part of this study revealed the existence of 137 species spread over 116 genera and belonging to 33 botanical families (Table 1).According to the analysis of these results, the most species-rich family is the Asteraceae, with 30 species (21.90%).This family is also considered the richest in Morocco, with 550 species (Fennane, 2012), followed by the Poaceae family with 21 species (15.33%).The Scrophulariaceae, Portulacaceae, Araceae, Convolvulaceae, Nitrariaceae, Frankeniaceae, Tamaricaceae, Cyperaceae, Fagaceae, Arecaceae, Primulaceae, Geraniaceae, Nyctaginaceae and Rubiaceae families are the least represented in this study area, with just one species (0.73%) each.The high representativeness of Asteraceae and Poaceae can be explained by the great capacity of their taxa to regrow (Diallo et al., 2015), given their presence in the majority of the surveys carried out, despite the differences that may exist between the habitats inventoried in terms of the nature of the substrate, exposition to trampling, the pressure of management and maintenance of urban spaces, etc.Thus, most Asteraceae and Poaceae are characterized by the production of large numbers of small seeds, which increases their chances of being disseminated more easily, especially by wind, and colonizing more environments after seasonal rainfall.
In terms of generic richness (Figure 2), almost half of the families (17 families) are known by just 1 genus.However, the Asteraceae family ranks first, with 24 genera, or 20.69% of the total.The Poaceae family, with 20 genera or 17.24% is in the second place.Four genera are the most represented in the study site, with 3 species each: Crepis, Chenopodium, Amaranthus, and Solanum.In turn, 13 genera are known from two species each: Erigeron, Carduus, Centaurea, Sonchus, Elytrigia, Sinapis, Sisymbrium, Lotus, Papaver, Salvia, Malva, Plantago and Oxalis.Note that the genus Silene is represented by only one species (Silene gallica L.), despite being considered the richest genus of vascular species in Morocco with 67 species and 16 subspecies, followed by the genus Ononis with 58 species and 24 subspecies (Fennane, 2012), but, in this study, the genus Ononis recorded only one species as well (Ononis natrix L.).

Biological types
In terms of life forms (Figure 3), according to Raunkiaer's (1934) classification of plant adaptation strategies to the environment, therophytes dominate the study area with a contribution of 48.90%.Next in descending order are hemicryptophytes (26.28%), geophytes (10.22%), and chamephytes (8.76%); this order of importance is in agreement with that found by (Rimani et al., 2019) in spontaneous weeds associated with saffron crops (Crocus sativus L.).Next come nanophanerophytes (3.65%) and finally phanerophytes (2.19%).Chafik et al. ( 2010) also showed the dominance of therophytes among weeds in the green spaces of the city of Berkane, noting that the two most common weeds in the city's green spaces are Cyperus rotundus L. and Cynodon dactylon (L.) Pers.These two species were also found in the Temara urban area according to this study, but in a lower abundance.The high rate of therophytes is mainly linked to the harsh climate and anthropogenic activities, which contribute to the degradation of conditions favorable to the establishment of new species (Hachemi, 2015).Thus, therophytes crowd out other life forms when environmental conditions become harsh (Yerou, 2022) as in the case of the urban environment.

Endemism, rarity, and threat status
The rarity rate in the list of species recorded (Table 2) is  Macaronesian islands (MC).Nationally, the Moroccan flora includes 640 species and 280 subspecies, representing 920 taxa endemic to Morocco and 4 species endemic to Morocco, Mauritania, and the Macaronesian islands (Fennane, 2012).

CONCLUSIONS
This work has shown the spontaneous floristic composition of the Temara urban area, with a fairly high specific richness for certain botanical families (Asteraceae and Poaceae) and limited richness for others.The predominance of therophytes in the study area (48.9%) was noted, as this biological type is the most adaptable to highly fragmented environments such as the urban environment.A clear predominance of the Mediterranean element compared with other biogeographical types was also observed.The conducted study recorded a low level of endemic taxa (two taxa out of 137), but the number of very rare taxa was quite high (10 taxa).These species and subspecies contribute to maintaining the phytodiversity of both the area surveyed and the country in general, making their preservation a priority for various stakeholders.This study is limited to vascular plants, but bryophytes and lichens also represent a considerable proportion of the vegetation in the urban ecosystem, which can be the subject of similar studies and analyses.

Table 1 .
Richness and specific contribution of inventoried families

Table 2 .
Degrees of rarity, endemism, and threat categories of recorded taxa