The objective of this study is to determine the influence of soil physico-chemical factors on the spatial distribution of matorrals in the plain from Remchi to Béni-Saf located in the western region of Algeria. This study informs us of the relationships that soil can have on the diversity of matorrals. On the bioclimatic level, the region is characterized by semi-aridity accentuating the phenomena of thérophysation. Soil analyzes carried out using known methods (Stokes Particle Size Method, Electrometric Method for pH, 1/5 Extract Method for Electrical Conductivity, Bernard Calcium Method for CaCO 3, Anne Method for Organic Carbon). The results show a textural diversity; sandy-muddy “Remchi”, sandy “Rachgoun 1 and Rechgoun 2”, not far from Béni-Saf. The low clay content (Remchi: Profile 1: Horizon 1: Clays 10%, Profile 2: Horizon 1: Clays 16%, Profile 3: Horizon 1: Clays 5%, Rechgoun: Profile 1: Horizon 1: Clays 3%, Profile 3: Horizon 1: 2% Clays and Horizon 2: 3% Clays) leads to poor structural stability leading to degradation of the soil surface through erosion. The latter is revealed by the presence of small erosion claws visible on these rough slopes or almost.
The Mediterranean region of Matorral has a very diversified range of soils because of the great variability of the natural factors (climate, vegetation, physiography, geology and lithology) which condition their formation and distribution. Soil is the natural formation of surface loose structure of varying thickness resulting from the transformation of the parent rock, underlying under the influence of various chemical and biological physical process; it is a living environment, whose quality can be irreversibly altered by inappropriate human interventions. Several works have been devoted to him [
- Methodology;
- Soil analyzes;
- Interpretations of the results;
- Conclusion.
The Remchi station is close to the national road No. 22 Remchi-Beni-Saf. It rises to an altitude of 60 m and presents the following Lambert coordinates:
• 1˚42' West longitude;
• 35˚19' North latitude.
The station is on a slope of 30% and is limited by plots of cereal crops. The vegetation cover rate is 60% to 70% represented by some Chamephytes Urginea maritima, Chamaerops humilis (doum) and some annual species.
The Rachgoun 1 station is approximately 1.2 km from the crossroads of the national road 22, on the path leading to Béni-Saf, it rises to an altitude of 35 m and has the following Lambert coordinates:
• 1˚41' West longitude;
• 35˚22' North latitude.
The rate of vegetation cover varies from 60% to 70% on a slope of 30% to 40% represented by a vegetation composed largely of: Olea europea, Chamaerops humilis, Urginea maritima and Calycotome spinosa.
The Rachgoun 2 station is about 6.8 km from the Rechgoun 1, it rises to an altitude of 16 m and has the following Lambert coordinates:
• 1˚43' West longitude;
• 35˚26' North latitude.
The rate of recovery of vegetation is 60% to 70% on a slope of 30% to 40% represented by a vegetation dominated by chamephytes: Chamaerops humilis, lavandula dentata, Urginea maritima and some annuals: Hordeum murinum, Bellis sylvestris, Avena sterilis.
In the first place, it was a question of finding an area where the Matorrals formations are considered as coming, for that we headed towards the slopes of orientation (North-South, North-East, etc. ...), where l micro topographical exposure (incline slope, butte, etc. ...) was taken into account in our approach.
In order to know the edaphic factors governing the distribution of the studied matorrals, we followed a methodology comprising two stages, the first in the field and the second in the laboratory where physical and chemical analysis were carried out.
We took our samples at the level of the profiles in relation to the inclination of the slope. For each station, we have determined 3 fairly wide profiles along the slope, from each profile we took two samples: one in surface (surface horizon) and the other in depth (depth horizon), that is to say 6 samples taken at each station; The methods used are those outlined in [
The soil samples were sent to the soil testing laboratory for different treatments.
Physical AnalyzesGranulometry;
Stokes particle size method.
Electrometric method.
Bernard calcimeter method.
Anne method [
Knowing the amount of dichromate needed for this oxidation, we can calculate the percentage of organic carbon and humus in the soil (the ratio% humus/% Cox = 1.724) [
Method of diluted extract or extract a fifth (1/5). The measurements are expressed in mS/cm.
The color of the soil, expression of the presence of organic matter, various elements (trace elements, macro elements) can vary from one profile to another and from one sample to another.
Our study stations are located in the upper semi-arid bioclimatic stage in warm winter and in the lower semi-arid in temperate winter.
According to the thermal classification of Debrach [
The bioclimatic classification according to the annual average temperature and “m” shows that the Béni-Saf and Remchi stations belong to the thermo-Mediterranean level.
1) Remchi station (
2) Rachgoun 1 (
2) Rachgoun 2 (
To know the soil characteristics on which the matorrals rest, it was essential to carry out a set of analyzes that highlight its physical and chemical nature. It is noted that the soils of the Matorrals studied occupy remarkably varied zones as much by the topographical location as by the texture and properties of the soil. The low clay content (Remchi: Profile 1: Horizon 1 clays 10%, Profile 2: Horizon 1: Clays 16%, Profile 3: Horizon 1: Clays 5%, Rechgoun Profile 1: Horizon 1: Clays 3%, Profile 3: Horizon 1: 2% Clays and Horizon 2: 3% Clays) leads to poor structural stability leading to degradation of the soil surface through erosion. This is revealed by the presence of small erosion claws visible on these rugged slopes. We note, among other things, a decrease in the percentages of sands towards depth horizons (Tables 1-3 and Figures 5-7). How can we explain this
Profile 1 | Profile 2 | Profile 3 | ||||
---|---|---|---|---|---|---|
Horizon 1 | Horizon 2 | Horizon 1 | Horizon 2 | Horizon 1 | Horizon 2 | |
Depth (cm) | 0 - 15 | 15 - 80 | 0 - 8 | 8 - 60 | 0 - 20 | 20 - 80 |
Granulométry (%) | ||||||
1) Sand 2) Silts 3) Clay | 73 17 10 | 65 17 18 | 44 40 16 | 54 31 15 | 79 16 5 | 62 27 11 |
Type of texture | Sandy-Silty | Sandy-Silty | Sandy-Silty | Sandy-Silty | Sandy-Silty | Sandy-Silty |
Organic matter 4) OM (%) 5) Estimation | 5.16 Very strong | 4.64 Strong | 4.90 Strong | 4.40 Strong | 4.60 Strong | 4.30 Strong |
Minéral réserve 6) CaCO3 (%) 7) Interprétation | 11.28 Average | 8.71 Average | 26.15 Strong | 22.00 Average | 21.53 Average | 16.92 Average |
Soil solution | ||||||
8) pH 9) Estimation | 7.02 Neutral | 7.08 Neutral | 7.02 Neutral | 7.02 Neutral | 7.34 Neutral | 7.34 Neutral |
10) Electric conductivity 11) Estimation | 0.65 Little dirty | 0.44 Unsalted | 0.76 Little dirty | 0.67 Little dirty | 0.87 Little dirty | 0.67 Little dirty |
Munsell coloring | 10 YR 5/4 | 5 YR 5/4 | 5 YR 4/4 | 10 YR 4/3 | 7.3 YR 4/3 | 5 YR 4/6 |
Profile 1 | Profile 2 | Profile 3 | ||||
---|---|---|---|---|---|---|
Horizon 1 | Horizon 2 | Horizon 1 | Horizon 2 | Horizon 1 | Horizon 2 | |
Depth (cm) | 0 - 15 | 15 - 80 | 0 - 15 | 15 - 100 | 0 - 15 | 15 - 80 |
Granulométry (%) | ||||||
1) Sand 2) Silts 3) Clay | 83 14 3 | 90 8 2 | 89 9 2 | 79 19 2 | 92 6 2 | 79 18 3 |
Type of texture | Sandblaster | Sandblaster | Sandblaster | Sandblaster | Sandblaster | Sandblaster |
Organic matter 4) OM (%) 5) Estimation | 5.18 Very strong | 2.86 Average | 4.95 Very strong | 2.90 Average | 4.50 Very strong | 2.80 Average |
Minéral réserve 6) CaCO3 (%) 7) Interprétation | 22.05 Average | 17.94 Average | 10.76 Average | 20.00 Average | 14.35 Average | 18.46 Average |
Soil solution | ||||||
8) pH 9) Estimation | 7.06 Neutral | 7.12 Neutral | 7.06 Neutral | 7.07 Neutral | 7.04 Neutral | 7.05 Neutral |
10) Electric conductivity 11) Estimation | 0.59 Unsalted | 0.62 Unsalted | 0.46 Unsalted | 0.46 Unsalted | 0.50 Unsalted | 0.49 Unsalted |
Munsell coloring | 2.5 YR 3/4 | 5 YR 3/4 | 7.5 YR 4/4 | 7.5 YR 4/6 | 7.5 YR 3/4 | 5 YR 3/3 |
Profile 1 | Profile 2 | Profile 3 | ||||
---|---|---|---|---|---|---|
Horizon 1 | Horizon 2 | Horizon 1 | Horizon 2 | Horizon 1 | Horizon 2 | |
Depth (cm) | 0 - 15 | 15 - 80 | 0 - 15 | 15 - 80 | 0 - 20 | 20 - 100 |
Granulométry (%) | ||||||
1) Sand 2) Silts 3) Clay | 84 12 4 | 84 14 2 | 81 14 5 | 82 14 4 | 85 12 3 | 68 23 9 |
Type of texture | Sandy | Sandy | Sandy | Sandy | Sandy | Sandy - Silty |
Organic matter 4) OM (%) 5) Estimation | 5.17 Very strong | 3.25 Strong | 4.90 Strong | 3.10 Strong | 4.55 Strong | 2.90 Average |
Minéral réserve 6) CaCO3 (%) 7) Interprétation | 17.43 Average | 24.10 Average | 22.56 Average | 22.05 Average | 26.66 Strong | 28.20 Strong |
Soil solution | ||||||
8) pH 9) Estimation | 7.00 Neutral | 7.11 Neutral | 7.12 Neutral | 7.12 Neutral | 7.08 Neutral | 7.13 Neutral |
10) Electric conductivity 11) Estimation | 0.49 Unsalted | 0.49 Unsalted | 0.05 Unsalted | 0.53 Unsalted | 0.62 Unsalted | 0.55 Unsalted |
Munsell coloring | 7.5 YR 5/4 | 2.5 YR 5/8 | 5 YR 5/8 | 5 YR 5/4 | 5 YR 4/6 | 5 YR 6/4 |
phenomenon, which tends to generalize across all profiles? In our opinion, this sequential differentiation is due to colluvial and alluvial phenomena in these steep slopes. Soils affected by this sensitivity are often rich soils (Remchi: Profile 2: Horizon 1: silt 40% and Horizon 2: silt 31%, Profile 3: Horizon 1: silt 16%) in silt and/or fine sand (Profile 1: Horizon 1 sands 73% and Horizon 2: sands: 64%, Profile 2: Horizon 1: Horizon 2: sands 54%, Profile 3: Horizon 1: sands 79% and
Horizon 2: Sands 62%). The silts have a weak cohesion and are very fine particles. They are therefore easily detached from the soil matrix and easily transported by runoff since they are small. Fine sands have an even weaker cohesion. Coarse sands have a very weak cohesion, because they are also larger sediments than fine silts and sands. Easily transported by the water these run down the slopes. A very approximate range for an ideal clay content would be between 15% and 30% - 40%. Below 15%, the structural stability becomes relatively low and the soil easily eroded; beyond about 40%, the soil tends to be heavy, with high water retention and a structure tending to be massive [
The authors declare no conflicts of interest regarding the publication of this paper.
Meftah, F.Z., Benabadji, N. and Merzouk, A. (2019) Physico-Chemical Complex of Matorral Soils of the North Western Region of Algeria. Open Journal of Ecology, 9, 134-144. https://doi.org/10.4236/oje.2019.95011