(BNEDER 2006)
(BNEDER 2006)
| Livestock Research for Rural Development 33 (12) 2021 | LRRD Search | LRRD Misssion | Guide for preparation of papers | LRRD Newsletter | Citation of this paper |
The natural landscape of the Algerian steppe regions is essentially made up of a characteristic plant association of the Algerian highlands. These associations represented by Stipa tenacissima, Arthophytum scoparium, Lygeum spartum and Artemisia herba-alba are among the most important plant formations that make up the Algerian steppe regions. For centuries, this steppe has been exploited by nomadic tribes who lived on pastoral livestock transhumance of small ruminants. Fragmented and destabilized by inappropriate policies and projects during and after French colonization, this collective and regulated exploitation of rangelands gave way to a competitive family mode of exploitation. Indeed, the steppe is undergoing degradation, of which the rate and the intensity are accentuated more and more, leading to a reduction in biological potential and a disruption of ecological and socio-economic balances. The action of man and his main livestock activity and the practice of a rainfed cereal crop are at the origin of this degradation coupled with a harsh climate and irregular and rare rainfall have been stumbled for several decades,, against a demographic increase and inadequate use of natural resources. This very advanced state of degradation of the steppe requires urgent action because of the vital role of buffer zones in these regions against the advance of the desert. The implementation of a program to safeguard and restore these regions should constitute a major objective for the country in the medium and long term. It is in fact a question of rehabilitating these regions by reconciling man with his natural environment.
In order to cope with this difficult situation, the state has implemented a proactive approach based on several major programs to combat drought and desertification. In addition to the traditional actions of the ex "Green Dam", it was decided to carry out sectoral actions of land development, pastoral management, reforestation and fruit plantations, as well as measures of defending setting of Stipa tenacissima formations in steppe zone. However, it was found that, the methods and means used were not sufficient to curb the effects of drought and resources degradation. This failure is due to the successive strategies adopted for the development of the steppe region, and the lack of effectiveness of the methods used for the identification and formulation of projects, as well as for their implementation and monitoring.
It is in this perspective that our article comes and generally aims, after a reminder of the first elements of diagnosis of the Algerian steppe regions and the problems of the latter, it deals with a characterization of the large existing formations in these regions and the main factors that threaten them, to lead at the end of this contribution to the necessary recommendations aimed at the restoration and rehabilitation of the entire steppe regions.
Keywords: desertification, formations, plains, rangelands, recommendations, Stipa tenacissima, training
The high steppe plains of Algeria constitute a natural barrier which acts as a bulwark against the advance of the desert (Roselt / OSS / Algeria 2005) Unfortunately, the changes, the excesses and the risks that the steppe undergoes endanger the entire Tell region as a direct result of silting up and desertification. Indeed, the steppe plant formations, are permanently subjected to a sheep pasture with a pastoral load largely exceeding its real possibilities. The overall reduction of plant cover under the effect of overgrazing and other inappropriate practices, mark the steppe of today (Bencherif 2011, ICARDA 2005, Bensouiah 2003). Faced with this alarming situation; the public authorities have carried out many development actions since independence. But, for lack of sufficient studies, and lack of effective participation of the populations concerned in these various forms of public intervention, these have not produced the expected results.
Thus, a lot of work has been carried out on these areas, including those of Aidoud (1983, 1989), for the study of steppe grazed ecosystems in the high plains of Algeria-Oran. Other even older authors (Marion 1956 in Bakhti 2001) are interested in the problems of new modes of breeding, overgrazing, pastoral load and their impact on the degradation of the steppe, desertification and the regression of the Alfa species of these areas Aidoud (1994), Aidoud and al (1996), Benabdeli (2000), Bencherif (2011, 2013).Others, has been devoted to surveys and analyses of the phytodiversity of steppe vegetation Celles (1975), Djebaili (1978) and Chalane (2016)or to the restoration, preservation and the promotion of steppe ecosystems has been also the subject of much work, Bousmaha (2012), Benaredj and al (2010).
It is in this order of ideas that our article fits and which revolves around three parts: we will first approach a detailed presentation of the Algerian steppe regions and the problematic then we will expose the large existing formations and the main factors which threaten them. At last we will end our contribution with a conclusion and some recommendations aimed at the rehabilitation and preservation of these spaces; with a view to broadly identifying the possibilities for a lasting exit from this bad patch.
Algeria is a huge country; it stretches over nearly 238 million hectares, and opposes two large territorial groups, the Sahara with more than 2 million km², and northern Algeria. It runs along the Mediterranean coast for 1622 km and sinks for more than 2000 km into the African continent, in the heart of the Sahara. Algerian geography defines three major physical units characterized by great diversity (Georges 1985 and Merouane 2013). To the north, we find the Tell Mountains which represent only 4% of the territory, but with a forest heritage estimated at 4.7 million hectares and a mountainous area covering 12 million hectares. The Saharan domain occupies the greater part with 87% of the national territory, represented by 200 million hectares; composed essentially of vast and mobile dune ridges. At the end between the Tellian Atlas in the North and the Saharan Atlas in the South, we find the steppe. This occupies an area of 32 million hectares, sensitive to desertification, including 12 million hectares of pre-Saharan rangelands in an arid and semi-arid environment and 20 million hectares composed of steppe rangelands, which represent nearly 8.37% of the national territory. These include 15 million hectares of proper steppe, distributed over several wilayas (Map 1.) and 5 million hectares of cultivated land, scrubland, forests, and unproductive land (Bencherif 2011).From a bioclimatic point of view, many researchers like (Capot-Rey 1953, Quezel 1965, Celles 1975, Djebaili 1978, Le Houerou and al 1979; Pouget 1980, Le Houerou 1985, Djellouli 1990) in (Bousmaha 2012), agree to delimit these steppe spaces in the North by the 400 mm isohyets which coincides with the extension of cereal crops in dry land and in the South, by the 100 mm isohyets which represents the southern limit of the extension of the Alfa ( Stipa tenacissima). The same authors indicate that from the point of view bioclimatic stages; those of the Algerian steppe range from the cool lower semi arid to the cool upper arid.
The Algerian steppe, in addition to its geographical location in arid and semi-arid regions and its climatic characteristics, is particularly vulnerable to desertification. It has been the object of ecologically unsustainable exploitation and desertification, that gains more and more land and the assessment carried out on the entire steppe of the national territory has shown that nearly 70% of the total potentially arid lands productive areas are affected by natural degradation (Aidoud 1989, Hadeid 2008).This steppe, which has provided peasants with goods and services for centuries, has in recent decades considered many constraints. Animal overload on these routes, poor management of soil and water resources by unsuitable farms for cultivation and even the extension of rainfed or sometimes irrigated agriculture unsuited to the conditions of the natural environment, all of these factors, coupled with the galloping demography and prolonged and repeated droughts in these regions, have contributed to soil and vegetation cover degradation and desertification (Boukhobza 1976 and 1982, Montchaussé 1977, Weexteen 1977, Couderc 1979, Aidoud 1994, Bedrani 1994, Hadeid 2008, Nedjraoui and Bédrani 2008),This land degradation and desertification, which is in its most advanced stage, result in the reduction of biological potential and the disruption of ecological and socio-economic balances (Le Houérou 1985, Aidoud 1996, Bedrani 1999).
Several authors who have worked on this space come to the same conclusion (Le Houérou 1985 and 1995 in (Rekik 2015), Djelouli and Nedjraoui 1995, Aidoud 1996, Benabdeli 1983, 1996 and 2000, Nedjraoui 2004, Benaredj et al 2010).This pressure resulted in a very advanced regression of the Stipa tenacissima and Lygeum spartum facies, Aidoud andt al (2006), which occupied only 32000 ha in 2007 compared to 179000 ha in 1987; an average annual loss of 4900 ha Benguerai (2009), Of the 32 million Algerian steppe territories, 12 million hectares are in an advanced state of degradation. The DGF (1997) data on desertification sensitivity cited by benabdeli et al (2008) indicate that 5% of this area is desertified, 15% very sensitive, 25% sensitive to desertification or a total of 45% of land in a fairly advanced and often irreversible process of degradation.
The steppe vegetation is of very unequal value, both for its floristic and its density composition. Over the 20 million hectares, if we attribute the areas of crops, forests and unproductive areas; we have only 15 million left hectares of grassy steppe and chamaephytic vegetation constituting the real areas of the rangelands. The importance of the share of rangelands (that to say more than 80% of the total steppe area in 1995), is linked to the very vocation of this pastoral space (Bousmaha 2012). The Algerian steppes are dominated by 4 major types of plant formations and azonal formations (psammophiles and halophiles) which represent habitats and a reservoir for animal and plant species (Map 2.). These are the steppes of Alfa (Stipa tenacissima), the steppes of white sagebrush (Artemisia herba alba), the steppes made from esparto (Lygeum spartum), and finally, the steppes of Arthrophytum scoparium (remth) Moulay and al (2012). The few dayas represent a habitat of trees and shrubs of Pistacia atlantica (Atlas Pistachio) and Ziziphus lotus (Jujube). The azonal steppes are represented by a vegetation of psammophytes based on Aristida pungens and Thymellaea microphyla or even shrub steppes of Retama retam. The halophytic formations are located at the level of the chotts and are represented by adapted species such as Atriplex halimus and Salsola vermiculata. (Nedjraoui and al 2008), Moulay and al (2012).
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| Map 1. Pastoral and agro-pastoral Wilayas (BNEDER 2006) |
Map 2. Map showing the distribution of rangelands by plant formation group (BNEDER 2006) |
These steppe ecosystems have an essentially pastoral vocation. Today, they have a strong tendency to deteriorate, resulting in the reduction of biological potential and the breakdown of ecological and socio-economic balances.
The White Sagebrush is an herbaceous plant with small, pubescent leaves and woody, branched stems, of 30-50cm. The phrenological variations observed on White Sagebrush show a very advanced adaptation of the species to the environment and in particular the drought of the climate (Rodin and al 1970, Aidoud 1983). During the summer period the plant reduces its leaves and as a result, the decrease of the perspiration surface due to the high temperature is one of the most effective morphological adaptations in this plant species Evenari and al (1975).
In Algeria, these formations are found in more or less humid areas, dayas and unsalted depressions and are localized in the upper and middle arid stages with cool and cold winter and with precipitation ranging from 100 to 300 mm (Pouget 1980). Thus they colonize glazes with soils generally loamy to clayey-loamy soils, crusted or not, and compacted soils with relatively low permeability and significant runoff (Aidoud 1988) (Celles 1980 in Ayad et al 2007). It is therefore a natural means of combating erosion and desertification (Benjilali and Richard 1980, Bensegueni 1989 in Ayad and al 2007).They cover 3 million hectares (in potential areas). It is a mainly forage plant, highly valued by livestock as winter pasture (Nabli 1989) because it has a high forage value of 0.45 to 0.70 FU/kg DM (Nedjraoui 1981). White sagebrush steppes are often considered the best rangelands (3 ha/sheep) because of their energy value (Aidoud 1989). The same author notes in south Oranais that the production of white sagebrush varies between 104 and 636 kg DM/ha; the productivity being 340 kg DM/ha/year. The production of ephemerophytes varies between 23 and 407 kg DM/ha. That of therophytes, which constitute the main part of the flora (75%), is between 0 and 264 kg DM/ha.
The esparto or false Alfa supports clay and slightly salty soils and colonizes the edges of the shallows as well as the wetter soils of plateaus rich in fine elements. Thus it occupies the erosion glazes encrusted with a wind veil on limestone brown soils, halomorphs in the areas of the chotts (Photo 1.). Esparto-based steppes are found in upper and middle arid bioclimates in cold and cool winters (Bensaid 2006). It is a poor pasture for cattle and is grazed only at the time of the aerial budding of the rhizome (March-April) (Boukhlifa 1977 in Ben Kadour 1991). These steppe formations are rarely homogeneous and cover 2 million hectares. Lygeum spartum is of low pastoral interest (0.3 to 0.4 FU/kg DM). The productivity relatively high, (110 kg DM/ha/year), is due to their floristic diversity in annual and small perennial species, which gives these rangelands a significant pastoral production of 100 to 190 FU/ha/year and a load of 2 to 5 ha/sheep (Nedjraoui 2001).
They form Chamaephytic bushy steppes with an average cover of less than 12%. The main characteristic species are represented by perennials to which are added during the wet period, various annual species often referred to as ephemerrophytes (Roselt/Algeria 2005), Regagba (2012), Mallem and al (2017). Some authors such as (Unesco 1978) unfortunately consider; ecosystems where dominate Arthrophytum scoparium, Peganum harmala, Stipa retorta and many other very ephemeral annual species such as degrading ecosystems or those unable to maintain the surface layer of the soil and avoid the acceleration of desertification processes. On the other hand, other studies (ROSELT/Algérie 2005), assert that the steppe of remth, because of its richness in annual herbaceous plants developing during the humid period, constitutes a good spring rangeland that persists for several months in the year. They are located in the southern part of the steppe zone. The poor environmental conditions, xerophilia (20 to 200 mm/year), thermophilia, hot and cool variants, poor soils, brown limestone with clogged slabs or serozems make these steppes rangland that have a rather low pastoral interest, and its annual production judged as average (Moulay and al 2011). The energy value of the remth is 0.2 UF/kg DM. The average annual production varies from 40 to 80 kg DM/ha and the pastoral productivity is between 25 and 50 FU/ha/year with a pastoral load of 10 to 12 ha/sheep. This type of steppe is mainly exploited by camels (Nedjraoui 2001)
The Alfa is a grass characteristic of the steppe area. It grows spontaneously in Algeria, Morocco, Tunisia, Tripolitania and Europe (Benchrik and al 2002). It grows in the semi-arid and high plateaux regions of North Africa, as well as in southern Spain, where it is very popular Sidi Ali (1976)in (Benchrik and al 2002). Alfa also develops in the tell and the area that was previously called Alfa Sea. The Alfa is also develops in the tell and the area which was previously called “the Alfa Sea” that is located in Algeria.
It is bounded to the north by a line running from the border of Morocco to Tunisia (Abdelkerim 1984) in Bencherik and al 2002). This grass forms circular tufts gradually hollowing out in the centre, in the number of 3000 to 5000 on average per hectare in a normal stand Photo 2. in a degraded stand, the number falls from 1000 to 2000 tufts (Boudy 1952).
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| Photo1. Lygeum spartum formation, district of Roggassa, wilaya of El Bayadh. Boukerker H 2014 |
Photo 2. Stipa tenacissima formation, locality of Essekine wilaya of El Bayadh. Boukerker H 2014 |
According to Boudy (1952) and Djebaili (1984), the Alfa is mainly abundant between 200 and 400 mm of rainfall, but can live where this slice drops to 150 mm. The lower limit for the development of Alfa is 150 mm of water per year. Aidoud (1983) notes that Alfa can supports the cold and develops from the thermal variants with hot winter (m = + 9, 1° c) to the cold winter (m = - 1, 8° c). Khellil (1995), adds that Alfa tolerates prolonged snowfall well and its tufts play an important role in fastening materials, thus increasing the thickness of the soil. Aidoud (1983) also describes three types of Alfa according to its ecological situation and distinguishes? the Alfa of glacis, the Alfa of silted and finally that of the slopes.
Alfa does not show any edaphic requirement but comes on light soils formed of silica, limestone and stony, little clay, with a pH between 7 and 8.5, it flees flooded depressions, heavy where the clay exceeds 12 to 15% of the elements and salty, not suitable for the Alfa (Bencherik and al 2002, Mohamed 1995 and Khelil 1995, Marion 1956 in Bakhti 2001). Alfa grows generally in deep soil stations (10-15cm) and on dry skeletal soils with silty-sandy textureKaabech (1990).
The steppes of Stipa tenacissima, covering 4 million ha in 1975, have high ecological amplitude (Achour 1983, Kadi-Hanifi 1998). The average pastoral productivity of this type of steppe varies from 60 to 150 FU/ha depending on the cover and the floristic procession (Nedjraoui 1981, Aidoud 1983, Nedjraoui 1990). The low pastoral value (10 to 20/100 on average) allows a load of 4 to 6 hectares per sheep. In the pre-Saharan rangelands, this pastoral production in forage units reaches a value of about 34 to 84 FU/ha (Melzi 1991).
According to (Arrour 1991), the grazing at Alfa is not of great pastoral interest and is grazed by cattle, whereas sheep only consume young leaves and inflorescences that appear in good season. These organs represent between 5 and 10% of the aerial phytomass and have a high energy value of about 0.6 UF/kg MS due to their high protein nitrogen content (Djebaili 1987). However, the floristic procession, especially of the herbaceous species, is a much appreciated pastoral background at the beginning of the winter and in the spring, of which it is observed that the regression of the Alfa resulted in a decrease of the floristic richness. In addition to these 4 types of steppes, there are 2 other types but they are not important:
They are linked to the sandy texture of the surface horizons and the contributions of Aeolian origin. These formations occupy an estimated surface area of 200,000 hectares. They follow silt corridors and are more common in arid and pre-Saharan areas. The psammophyte formations are usually grassy steppes with Stipagostis pungens andThymelea microphylla or even shrub steppes of Retama retam. The cover of psammophytic vegetation is often greater than 30%, giving pastoral range from 200 to 250 FU/ha (Nedjraoui 1981).According to the results of the ROSELT program of 2003, psammophiles which were non-existent in 1978 in the west have experienced an extension due to a greater silting during up the drought period of 1981-87. The recovery of psammophytic vegetation is often greater than 30% thanks to the proliferation of annual species Amaouche (2011).
The concentration and unequal distribution of salts in space has given rise to a particular formation of steppic vegetation and has created a typical zonation of highly appetizing hallophitic around salty depressions. These steppes cover 1 million hectares. Halophilic vegetation is very palatable(Rekik 2015). The most common species in these formations are Atriplex halimus, Atriplex glauca, Salsola sp, Suaeda fruticosa and Frankenia thymifolia (Bensaid 2006). This type of steppe is much sought after by pastors and its pastoral value is around 300 FU/ha (Nedjraoui 2001). It is especially the Salsola and also the Atriplex which constitute excellent pasture whose permanence during the dry season ensures the feeding of many herds of the high plains, while others only offer them insufficient food (Guiraa 2005 in Djaballah 2008).
Today, the situation of the steppe is indeed very worrying. Le Houérou 1985, Djellouili and Nedjraoui 1995, Aidoud 1996, Nedjraoui 2004, Nedjraoui and Bédrani 2008) in Khader 2014,confirm that in addition to natural factors, anthropogenic actions have acted on the steppe ecosystems beyond their limit of resistance, thus leading to an alarming rate and intensity of degradation; and there is a breakdown in ecological and socio-economic balances. A harsh climate, an increase in population and an inadequate exploitation of natural resources, acting in synergy, that contributes to the degradation of the steppe.
Erosion can be slow and relatively undetected. It can also occur at an alarming rate and cause heavy losses of arable land. It accentuates the process of desertification and it depends on the vegetation cover; if the latter is greater than 30%, the bushy vegetation reduces the wind speed and we witness a deposit of material. According to Viramontes (2000), if the cover is less than 30%, the wind operates a sorting by taking away fine particles (such as fine sand and clay) and leaving behind a skeletal and stony soil that is not conducive to recolonization by vegetation (Arour 2011).On vegetation-free soil, rain drops and strong winds can pull or break up aggregates and disperse soil particles. The effects of erosion are multiple and can appear at different levels, namely; soil compaction, soil depletion of organic matter, degradation of soil structure by clogging and smoothing of scratches and grooves, poor internal drainage, soil salinization and acidification Benbrahim et al (2004).
Even thus the paths of the animals are starting points for erosion, and the consequences are sometimes serious and can cause soil loss of 150-300 t/ha/yr in cleared steppes Le Houerou (1995) in Rekik 2015). Based on recent work, Gazi and Lahouati (1997), show that 600,000 ha of land in steppe areas are desertified completely without the possibility of biological recovery and nearly 6 million hectares are threatened by the effects of water and wind erosion. This trend is likely to have dramatic consequences for the entire steppe ecosystem and the pastoral world of the region. Benabdeli (1983) in (Moulay and Benabdeli 2011) wrote in this sense: «Under the combined effect of overgrazing and droughts, the steppe at Stipa tenacissima is in an advanced state of degradation facilitating a process of desertification» Viramonte (2000).
At the same time as the steppe animal overload (22.5 million head in 2011 according to (MADR 2011 in Rekik 2015); demographic growth in the steppe has been exceptionally strong in recent decades, (less than one million inhabitants in 1954, more than seven million today (Abdelguerfi 2003). According to (Bencherif 2011), with its 7225408 inhabitants, the steppe is home to around 24% of the country's total population. This population is characterized by a very high growth rate.
The number was multiplied by 2.5 between 1966 and 1998 (Table 1). Population growth has affected both the sedentary and the sparse populations. It is composed mainly made up of pastoralist breeders practicing transhumance, while others are sedentary, where their main income is drawn from sheep farming in steppe areas. However, there has been a significant decline in nomadism which only persists sporadically (Khaldoun 1995). Pastoralists have changed their production system by combining cereal cultivation and livestock production.
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Table 1. Population trends in the steppe (Bencherif 2011) |
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Dates |
Population (inhabitants number) |
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Total |
Urbain |
Rural |
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1966 |
2 817 339 |
/ |
/ |
|
|
1977 |
3 843 090 |
13 165 484 (34.3%) |
2 526 542 (65.7%) |
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1987 |
5 390 549 |
2 666 024 (49.5%) |
2 724 525 (50.5%) |
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1998 |
7 225 408 |
4 216 866 (58.4%) |
3 008 542 (41.6%) |
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2020 (in anticipation) |
11 700 000 |
65% |
35% |
|
In Algeria sheep farming occupies the first class, with a rate of 78.46% in 2006, followed by goat farming with 15.01% which are characterized by slow evolution. With a percentage of 6.32%, cattle breeding; ranks in 3rd order. At the end, camel and equine breeding account for 1.14 and 0.62% of the national livestock respectively (Aoun 2008). Today, according to (Abdelguerfi 2003), some authors, and in the absence of other sources of income, population growth has exceptionally led to a significant increase in livestock, grazing in steppe areas and whose predominant component is the sheep breed; (about 80% of the livestock), continued to increase from 1968 to 1996 (6 million to 17millions head) against 4 million in 1954). In 1985, out of a national population of 15500000 heads, some 11500000 remained in the steppe (photo 3.).
In 1996, there were 17,301,000 sheep, 75% of which were concentrated in the Steppe zone (Bouchetata 2002. For its part (Madr 2010) in (Chalane 2016, gives a higher figure equivalent to 18 million heads, with the same proportion at the steppe level. While (Bencherif 2013), declare that the Algerian steppe supports 20 million heads.
In 1968, the Steppe rangelands with 1.6 billion FU (Chellig, 1969) fed 7890 103 sheep equivalents, giving a load of 1.9 ha / sheep eq. In 1996, the total number of sheep was equivalent to 19170103 and the actual load of the 15 million hectares, would correspond to 0.78 hectares for 1 sheep. eq. This overload of its rangelands led to a strong degradation of rangelands and that forage production is equivalent to about 1/3 of what it was in 1968, that is to say 533 million FU.
The potential pastoral load would be around 8 ha / 1 eq-sheep. and therefore 10 times greater than the actual load of the rangelands which gives rise to intense overgrazing which manifests itself in the herd being kept for too long on grazed areas taking a quantity of vegetation far greater than the annual production (Bensouiah 2003), (U.R.B.T 1981, Le Houerou 1985, Aidoud 1989, Kacimi 1996) in Nedjraoui 2004. Overgrazing tends to destroy the protective plant cover while trampling the surface of the soil powdery (wind erosion) and compacting it, which reduces its permeability, therefore its water reserves and increases runoff (water erosion) (Wachal 2007). Grazing brings perennials back to ground level and prevents flowering and fruiting of palatable annuals. It prevents natural regeneration and even contributes to the disappearance of palatable species and to the domination of other species, less palatable, poorly nutritious commensals, herbaceous plants or brushwood (Benabid 2002).
Today in the Algerian steppe zones, the balances between vegetation, soil and water are disturbed due to the practices of an anarchic cereal growing which encroaches on rangelands. It is also episodic and itinerant which, according to Abdelguerfi and Laouar (1997), destroys perennial plants that are replaced by annual or adventitious species unable to retain the soil, but which promote wind erosion Nedjraoui (2004), and weak yields obtained (2 to 5 qx / ha), that are far from compensating for the resulting loss of soil and the nuisances generated MA 1998, Le Houérou 2002. This cereal cultivation constitutes the main activity after breeding and for the needs of its extension, agro-pastoralists clear the plant cover which according to (Yagoubi 2008) and (Abdelguerfi 2003), the cultivated areas have increased from 1.1 million hectares in 1968 to 2.1 million hectares in 1990 as a result of clearing on fragile soils located outside the fertile lands of the bottoms of wadis or dayates (depressions) (Photo 4.). Thus, slash-and-burn agriculture, inappropriate plowing techniques and the number of passages of machinery used by agro-pastoralists certainly have an erosive action, by reducing the organic matter content of the soil, also decreases its biological activity, destroying the soil shallow horizon and sterilizing it, which leads to the degradation of soil biostructures most often irreversibly Boukong (2000), (Botticelli 2010), Wang et al 2018 in (Asri 2017). According to Chelig (1982), two million hectares are cultivated; an estimated 200000 hectares destroyed each year. The intensification of the breeding association and the increase in sheep herds that have resulted in the high cereal crop limits the free range and seriously hinders the exercise of the Achaba. As a result, rangelands are degraded and their forage production capacity is reduced (Bencherif 2000, Aidoud and Touffet 1996, Pluvinage 1995, Aidoud 1994).
For cooking and heating purposes, all kinds of vegetation; woody, semi-woody and herbaceous has been brutally overexploited. Even Alfa tufts are uprooted and burned to protect themselves from the cold Regagba (2012). Indeed, in the countries of North Africa only, it is noted that about 130000 ha of cultivated land (0.6%) are destroyed annually by water erosion, of which 40,000 ha are recorded for Algeria alone, Mallem et al (2017).
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| Photo 3. The pressure of animals on the steppe locality Ennamoussa, district of El Mehara; wilaya of El Bayadh. Boukerker H 2014 | Photo 4. The pressure of human on the steppe through
clearing and cultivation locality of El Bayadh. Boukerker H 2014 |
Like other countries, the Algerian steppe subject to regular threats related to climate variability, as well as the frequency and intensity of extreme events, the trend of which is increasing (Bensmira et al, 2015), where we are witnessing a weakening of agricultural and steppe ecosystems which results in a regression of plant cover and a disruption of traditional balances in a changing and increasingly uncertain climatic context (Poletti, 2018 ), (GIEC, 2014).
The stakes are therefore considerable for the steppe population and for its livestock activity which plays an essential role in this region. Faced with these threats, the challenge today is to ask what strategies should be adopted by the public authorities or agro-pastoralists of the region, through their know-how to deal with this situation that hinders socio-economic development and threatens their survival. Indeed, there are many options for conservation and expansion of specific services of ecosystem origin, which minimize negative effects or generate positive synergies with other services provided by ecosystems.
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| Photo 5. The dromedary animal of the steppe ecosystems. Boukerker H 2014 | Photo 6. The sheep breed "El Hamra",
animal of the steppe ecosystems. Boukerker H 2014 |
In terms of breeding, the dromedary and the sheep breed «El Hamra» (photo 5 and 6), are the emblematic animals of the steppe ecosystems and seem to be able to adapt not only to the meteorological constraints, but also to changes in more intensive farming systems. These changes lead to a better valuation of camel and sheep breeding products, whether milk, meat or wool, essential to ensure the food security of pastoral populations. Indeed; the remarkable physiology of the dromedary; indicates that it resists heat and dehydration as well as proteo-energetic and mineral undernutrition by practicing an ambulatory pasture and satisfying itself with resources of meager quality. (Bengoumi and Faye 2002, Bengoumi et al 2005, Chehma et al 2010, Faye and Bengoumi,2000, Richard et al, 1985a Yagil, 1985, Wilson 1989 in Bernard F 2013 ). The dromedary accompanies "isohyete migration" southward (Ozer and Erpicum 1995).
Thus, the sheep breed "El Hamra", which had as its distribution area the steppe zones of the extreme west of Algeria, namely the region going from Bougtob (w. El Bayadh) to Mecheria (w. Naâma) with a deployment on the south of the wilayas of Saïda and Tlemcen (Sebdou), today it remains only in more restricted areas. This breed is of good conformation, very rustic and adapted to the conditions of the western steppe and its morphological and zootechnical characteristics have even made it in the past a very appreciated breed on the ecological and socio-economic level, it is a race of ecological balance under extremely restrictive conditions (Gabina D1995). It grazes almost all types of plant formations, namely,Artemesia harba alba, Stipa tenacissima and Lygeum spartum formations. The size is smaller than that of the Arab breeds, but of excellent quality meat Chellig, (1992).
The numerous studies carried out since the 1970s on the steppes all show a significant decline in the vegetation cover of more than 50 percent and a serious decrease in the production of steppe ecosystems from 120 to 150 UF/year in 1978 to 30 UF/ha/year for degraded rangelands and 60 to 100 UF/ha/year for palatable rangelands (Aidoud and Nedjraoui 1992). In conjunction with this data, our field work which constitute a part of an FNR research project in different regions of the country (East, Central and West) and through comparative studies between different rangelands, confirm that there is a strong degradation of the vegetation cover characterized by the extension of the degradation indicator groupings such as;Hammada scoparia, Astragalus armatus, and Thymelaea microphylla groupe, etc.
From this dynamic, the importance of vegetation cover in maintaining the balance of the environment is clear. In Algeria, this stabilization element is very threatened. In addition to geographical factors, the territory of which 98% is made up of steppe or desert (DGF 2004) and climate (intra- and inter-annual fluctuations in precipitation) it is added, as an aggravating factor, the anthropozoogenic factor, in fact the lack of a clear and effective pastoralism policy has exacerbated the problem. Indeed, the Algerian steppe is the exercise area for extensive breeding representing a sheep herd of around twenty million heads which constitutes the main productive activity of the local population. Peasant farming habits and the low economic level of households seek to take advantage of these free resources through breeding practices. Studies confirm that towards the beginning of the 20th century, sedentarization, and the cultivation of land and population growth, mean that pastoral practices operate in a context of ecological imbalance.
The grazing livestock load of a pasture, which is the mass of livestock that can be supported by land without the risk of its soil being destroyed, is largely exceeded in the Algerian steppe areas, which has accentuated their degradation and desertification since the sparse vegetation, destroyed as soon as it grows, can in no way protect the soil. It is mainly sheep and goats that degrade the vegetative cover, since these animals cut the grass or even tear it down, and goats also destroy woody plants.
The reasoned logic management of developers opposes the strategies of breeders who seek to meet the immediate needs of their herds and families. It is a question of respecting the animal load by pastoral management based on the potentialities of the rangelands and this can be achieved only after the elaboration of studies on the evaluation and characterization of the agro-sylvo-cultural potentialities of these latter to find a balance between primary productivity and its consumption by herbivores. The public authorities should encourage breeders to improve and conserve their best animals (Camlin and the local breed "El Hamra), and thus by, organizing competitions and festivals, across the national territory with the awarding of bonuses, medals and others, benefits offered (vaccines, equipment, etc.) to the best. These actions must be initiated by the departments of agriculture of the wilayas.
Thus it is recommended to sow and mass forage plantations with perennial species of good quality adapted to the ecological conditions of the area. In this context, the Atriplex experiment in the El Bayadh region has yielded promising results. Maintaining a permanent pastoral carpet is a very effective way to protect these fragile areas. Even in cultivated plots, the rate of erosion and degradation of the vegetation cover can be limited; by limiting mechanized tillage, locating it, if necessary, in the context of development, at the level of potential agricultural areas (Dayas). The direction of ploughing must be parallel to the level curves and the establishment of bearings in steep areas. The use of agricultural and agro-industrial by-products and the forage resources of the Tell and the Sahara as livestock feed is also important. They have been neglected for a long time due to low prices and the ease of supply of feed grains. However, the development of new local forage resources is necessary for the success of a mechanism to combat the degradation and restore the forage production capacity of the steppe. This is an example of our ongoing research project on the recovery of waste and by-products from Date Palm as livestock feed, where the preliminary results are very encouraging.
In order to preserve soil resources from the risks of desertification, the technique of defending degraded perimeters is a very effective means, in some measures. The field experiments confirm through comparative studies of vegetation and surface conditions between protected and unprotected areas have shown that the technique is effective and the improvements resulted from this technique, are numerous and diverse. Indeed, the defending of a degraded steppe allows, after a more or less long period of time, the reconstruction of the major characteristics (cover, composition, production) of the pre-existing vegetation. This defense promotes the regeneration of perennials which, by trapping sand and organic matter and allowing the infiltration of rainwater, leads to the increase of the vegetation cover and its maintenance in times of erosion risk.
Moreover, the setting in defense of part of the courses necessarily increases the overload and the degradation of the neighboring courses. To avoid this, it is therefore necessary, as a first step, to increase the local fodder availability and to effectively support double transhumance.
The fight against erosion and the mitigation of desertification is incompatible with short-sighted farming, so much so that aid must be allocated to agro-pastoralists so that they agree to protect their livelihood. Thus, in the steppe areas recognized as the most sensitive, agro-environmental measures can be proposed to agro-pastoralists with financial aid for non-labor, direct seeding, and even for the implementation of grassy and windbreak strips, and this can only be achieved by including, necessarily, inter-sectoral coordination among the priority principles of development programs.
To restore degraded rangelands, it is necessary, on the one hand, to improve the holding water of runoff and to develop irrigated forage crops. In addition, more hydraulic structures adapted to the local environment are needed for the watering of livestock (low-flow drilling, wells, ponds, Djoubs, etc.), in order to reduce the pressure on certain points around the degraded routes. The Algerian steppe has undergone significant socio-economic, demographic, political and climate changes in recent decades. These changes have led to a change in livestock practices, particularly in terms of pastoral mobility. As a result, officials of the Ministry of Agriculture and Rural Development are called upon to review the old pastoral code dating from the 1970s, by updating some of its articles.
Indeed, the prerogatives of the first key body in the management chain of the steppe regions “the HCDS or the High Commission for Steppe Development”, must be broadened, on the one hand, to better fulfill its role of surveillance and preservation through the removal of reasonable pastoral resources, and to rehabilitate and restore degraded and valued areas. Thus, the public authority must decentralize certain decisions to achieve the desired results. HCDS must have full power to manage anthropozoic action, which is the aggravating factor of desertification.
Finally, the search for appropriate solutions to Algerian steppe ecosystems in reproduction difficulties must require a sufficiently in-depth knowledge of all the components and factors that govern their dynamism. The choice of well-targeted objectives and a team of different actors (researchers, breeders, officials and politicians), and rigorous coordination could detect solutions, be able to mitigate the decline and degradation of the environment while preserving an adequate threshold for the social and economic development of the steppe populations and to promote a strategy for the sustainable exploitation of all accessible resources, suitable or restorable, water, arable land and steppe pasture. More in-depth and wide-ranging studies covering all steppe regions will be necessary to clarify and complete our analyses, our diagnosis and our proposals.
Finally, the search for appropriate solutions for Algerian steppe ecosystems in reproduction difficulties must go through a sufficiently in-depth knowledge of all the components and factors which govern their dynamism. The choice of well-targeted objectives and a team of different actors (researchers, breeders, officials and policies), and rigorous coordination could detect solutions, be able to mitigate the decline and degradation of the environment while preserving an adequate threshold for the social and economic development of the Steppe populations and to promote a strategy for the sustainable exploitation of all accessible resources, suitable or restorable, water, arable land and steppe pasture. More in-depth and broader studies, covering all the steppe regions, will be necessary to clarify and complete our analyzes, our diagnosis and our proposals.
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