Subscribe Now Subscribe Today
Research Article

Accessible Forage Biomass of Browse Species in Matruh Area, a Mediterranean Coastal Region, Egypt

S. Z. Heneidy
Facebook Twitter Digg Reddit Linkedin StumbleUpon E-mail

Thirty-two sites with five different habitats were selected to represent study area to highlight the above ground as well as the actual available biomass for the grazing animals. The vegetation of the area was composed of both perennial and annual species, where the woody species (browse species) was the most common life-form. The highest total above-ground phytomass was 1897± 843 kg ha-1. Eighty six percent of perennials biomass was produced in the rocky ridge habitat during the wet season. While, the rest was produced in the saline depression habitat (675 ± 22.9 kg ha-1). The primary productivity of the pasture in these habitats was 169 ± 5.3 and 1083±674 kg ha-1 y-1 respectively. The highest biomass of accessible parts was produced in the non-saline depression habitat The annual average of the primary production in present study was 590± 117 kg ha-1 y-1, while that for the accessible production was 410 ± 39 kg ha-1 y-1. In addition the average Rain Use Efficiency (RUE) in the study area was 5.1 kg ha-1 y-1 mm-1 for accessible production and was 8.7 kg ha-1 y-1 mm-1 for primary production. Moreover, the Carrying Capacity (CC) in the study area ranged from 0.5 to 4.4 ha head-1 (mean = 1.7 ± 0.17 ha head-1). Calculating the Coefficient of Variation (CV), revealed that when the CV value was 1.2 for the primary production it reflected a great variation between sites, compared with a value of only 0.54 for accessible production. The average Production to Rain Variability Ratio (PRVR) was 2.4 for primary production and 1.1 for accessible dry matter production. The relationships between accessible production and each of carrying capacity (CC) and RUE were also studied. It was inversely related to the first (r = - 0.83**) while was directly related to the second measure (r = 0.45*).

Related Articles in ASCI
Similar Articles in this Journal
Search in Google Scholar
View Citation
Report Citation

  How to cite this article:

S. Z. Heneidy , 2003. Accessible Forage Biomass of Browse Species in Matruh Area, a Mediterranean Coastal Region, Egypt. Pakistan Journal of Biological Sciences, 6: 589-596.

DOI: 10.3923/pjbs.2003.589.596



Forage trees and shrubs play an essential and multiple role in the balance of the arid and semi-arid grazing systems exploited by man and his animals. This role becomes more important as the dry season grows longer (Le Houérou, 1980 and Heneidy, 2002). The world=s rangelands constitute an important global resources. Range has been defined by the society for range management as land which supports vegetation useful for grazing on which routine management of that vegetation is through manipulation of grazing rather than cultural practices (Tueller, 1988)

According to Hodgkinson and Harrington (1985) about two-third of the herbivores feed on artificial pastures developed from clearing native vegetation and sowing exotic forage plants. Water and nutrients are often added to boost the pasture production. The remaining one-third of herbivores feed on natural pastures where the pre-pastoral flora and fauna remain largely intact. They call these pastures as rangelands. It is worth mentioning that most of these Natural pastures are prevailing in arid and semi-arid zones.

The arid natural ecosystem within rainfall < 400 mm like that characterizing all the western Mediterranean regions under grazing is dominated by chamaephytes dwarf shrubs (Abdel-Razik et al., 1988a). In this region browse species are the main source of food for grazing animal (Heneidy, 1992). Also degradation of its rangeland is evident in many parts as a result of long history of overgrazing, over cutting, many social economic and cultural activities (Ayyad et al., 1983; Abdel-Razik et al., 1988a,b; Heneidy, 1992; Heneidy and El-Darrier, 1995).

In Egypt, the Mediterranean desert (west area of Alexandria city) vegetationally and floristically is considered one of its richest parts (Ayyad, 1978). This area especially the area around Matruh has an important role in the development and rehabitation programs. Also, this area is relatively rich in livestock number and grazing activity. Therefore, measurements of the biomass or standing crop has been of the interest to range workers for sometimes because herbivores depend directly upon plant phytomass for their food (Milner and Hughes, 1970).

Native vegetation, especially browse species (shrubs and sub-shrubs), in the Mediterranean arid zone are very important in the grazing system. The main economic value of browse species is grazing. Some of them have very high grazing value in terms of forage yield, season of production and forage quality. Productivity in rain-fed conditions may conveniently be assessed via the Rain-Use Efficiency factor (RUE) which is the quotient of the overall aerial phytomass production in kg DM ha-1 y-1 divided by the annual rainfall in mm (Le Houérou, 1984). The present study is endeavour to evaluate the biomass and primary production of the rangeland species especially shrubby ones; besides the evaluation of the accessible parts of the rangeland species in different sites; in addition to estimation and highlighting the Rain Use Efficiency and carrying capacity of the pasture.

Materials and Methods

Study area: The study area is located in the west of Matruh. It lies between meridians 31o 20- N and 26o 35- E. The area is a system of 3 main wadis :wadi Naghamish, wadi El-Garawla and wadi El-Zarek, which extend about 30 km southwards into the inland plateau with a width of about 10 km. This area has large variation in its topography and habitat types. The bioclimatic map of UNESCO (1977) designates its climate as arid with mild winters and warm summers. However, the amount of rainfall exceeds 250 mm in some areas, while it hardly exceeds 50 mm in others, with a mean annual of about 150 mm. The monthly average temperature ranges between 13.2oC in January and 26oC in August (Ayyad, 1978).

Standing crop phytomass and accessible parts: Thirty two sites were selected to cover the variation in physiognomy and phsiography of the study area. One hundred and twenty-eight randomized stands (each 100 m2) were distributed in all sites. Homogeneity of a stand was judged according to edaphic and physiographic features. The direct harvest method was used for phytomass determination according to Moore and Chapman (1986). All above-ground parts of different life-forms of the most common palatable species were excavated in each stand and directly weighed in the field. Representative individuals of each species were collected in each stand during two seasons, spring and summer (representing the wet and dry season), for standing crop phytomass determination and also to determine the vegetative and accessible parts (available parts) depending upon the morphology and configuration of the plant species (Heneidy, 1992). Carrying capacity was calculated according to Heneidy (1992). Nomenclature and identification were carried out according to Täckholm (1974) and the Latin names of species were updated following Boulos (1995).

Statistical analysis: Simple Linear correlation coefficient was applied (Snedecor and Cochran, 1968) to assess the relationships between primary and accessible production and Rain Use Efficiency (RUE) and carrying capacity (CC) besides Primary Production (P) to Rain Variability Ratio (P/RVR). Then Coefficient of Variation (CV) was also applied to predict variations in production at different sites (Le Houérou, 1988).


The common life-forms in the study area (Table 1) indicated that the woody species (browse species) were the most common (total 81 species). The total above-ground biomass (TAG), vegetative and accessible parts of different life-forms at 32 sites during the two seasons are represented in Table 2. The maximum above- ground biomass of shrubby species was attained at site 32 during spring (3607 kg ha-1), while the minimum was at site 13 (65.5 kg ha-1.). On the other hand, the sub-shrubs have two peaks of maximum biomass, the first one (mainly for Gymnocarpos decandrum and Salsola tetrandra) was attained at site 32 during spring (1113 kg ha-1), while the second (mainly Salsola tetrandra) was at site 10 (1090 kg ha-1). The minimum above- ground phytomass of sub-shrubs was attained for site 1 (3.4 kg ha-1) during summer. Herbs were recorded at all sites during spring except site 19. The maximum above-ground biomass of herbs was recorded at site 3 (908 kg ha-1), while the minimum was recorded for site 12 during the two seasons. The maximum biomass of annuals was recorded at site 12 (238 kg ha-1), while the minimum was recorded for site 20 (36 kg ha-1) during their growing season. The accessible biomass depends upon the life-forms and mostly on the configuration or architecture of the plant species. The percentages of accessible biomass of shrubby species for grazing during spring ranges from 20 to 49% at site 32 and site 26 respectively, while during summer it ranges from 19% at site 11 to 51% at site 7. Accessible percentage of biomass of sub-shrubs ranges from 89% (site 7) to 32% (site 21) during spring, while it ranges from 8.7% (site 9) to 15.3% (site 15) during summer. On the other hand, for herbs the percentage of accessible biomass mostly reached 100% from the above-ground biomass. For annuals the whole individuals may be accessible for grazing.

The total above-ground biomass (kg dry wt. ha-1) and the net primary production (kg dry wt. ha-1 yr B1) of the rangeland species are shown in Table 3. The highest total above-ground biomass of the perennials was attained at site 32 (4739 kg ha-1 during the wet season and 1411 kg ha-1 during the dry season), where, the contribution of shrubs and sub-shrubs was 75 and 23% respectively.

Table 1:
List of the common plant species in the Matruh area during their growing season

On the other hand, the lowest total above- ground biomass was attained at site 16 (455 and 337 kg ha-1 during the wet and dry season respectively). Perennial herbs play an essential role, especially during the wet season. Their contribution reaches up to 63% of the total above-ground biomass at site 3. The highest contribution of the annual species appears at site 13 (281 kg dry wt. ha-1 yr-1). The maximum of the net primary production for perennials was attained at site 32 (3328 kg dry wt. ha-1 yr-1), while the minimum was at site 5 (90 kg dry wt. ha-1 yr-1).

The accessible biomass (kg ha-1) and accessible production (kg ha-1 yr-1) of perennial and annual species for different sites are represented in Table 4. The highest accessible biomass for perennials was attained at site 32 (1273 kg ha-1) during the wet season, while the lowest is in site 27 (190 kg ha-1). On the other hand, during the dry season the highest accessible biomass was attained at site 3 and the lowest at site 1 (613 and 110 kg ha-1 respectively). Annuals attained their maximum at site 13 and the minimum at site 20 (281, 36 kg ha-1 respectively) during the growing season. The maximum accessible production for perennial species was attained at site 32 and the minimum was found at site 27 (938 and 10 kg ha-1 yr-1 respectively). On the other hand, the maximum of total accessible production for the pasture is attained in site 32 (999 kg ha-1 yr-1 ). The amount of rainfall ranged between 59.9±13 mm in the flat plateau habitat to 107.3±9.2 mm in the saline depression habitat (Table 6).

Table 2:
Total above-ground (TAG.), vegetative (Veg.) and accessible, (Acc.), biomass (kg ha-1) for different life-forms during spring and summer seasons at 32 sites of Matruh area

Table 3:
The total above-ground biomass (kg d.wt ha-1), the net primary production (kg d.wt ha-1 y-1 ) and Rain Use Efficiency (RUE) of different sites for perennial and annual species in Matruh area

The highest total above-ground phytomass of the vegetation was produced in the rocky ridge during the perennials was 86% while the lowest was in the saline depression (675 ± 22.9 kg ha-1) where the contribution of perennials was 91% (Table 5). However, the highest accessible parts were produced in the non-saline depression 864 ± 35 and 400 ± 64.3 kg ha-1 during wet and dry seasons respectively.

The primary productivity of the pasture in different habitats ranged from 169 ± 5.3 to 1083 ± 674 kg ha-1 y-1 in habitats of the saline depression and rocky ridges respectively (Table 6). The accessible production level reached its maximum in the habitats of rocky ridge (499±165 kg ha-1 y-1) while the minimum is attained in the saline depression (149.5±1.8 kg ha-1 y-1).


For biologists and rangers, it is very important to have knowledge about the production of rangeland species for range management. Measurement of plant biomass or productivity has been of interest to range workers and ecologists for some times because herbivores depend directly upon plant biomass for their food (Milner and Hughes, 1970). On the other hand, any ecological argument in land use planning in arid rangelands should be based on a thorough knowledge of the harvestable primary productivity. Study of the vegetation of study area (Heneidy, 2002) indicated that it consists of 39 perennial species and 43 annuals. The grazeable (mostly new-growth) phytomass is either accessible or non-accessible to the grazing animals due to morphological configuration of the plant. A portion of the accessible phytomass is actually grazed by grazing animals and another portion is left over (Heneidy, 1992).

The present study revealed that the study area was vegetatively rich and the woody species were the most abundant life-forms. The woody species were considered the skeletal part of the grazing system in arid ecosystem (Abdel BRazik et al., 1988a). The grazing system represented 60 to 80% of the utilization land of North Africa in terms of economic output (Le Houèrou, 1993). In the study area most of the land is used as grazing land.

Most perennial species exhibited their greatest vegetative activity during winter and spring and they were less active or dormant during summer. This observation agrees with that noticed by Abdel-Razik et al. (1988a) at Omayed in the northwestern region.

Table 4:
Accessible biomass (kg ha-1) net primary production (kg ha-1 y-1), Rain use efficiency (RUE) and Carrying capacity (CC) of different sites for perennial and annual species in Matruh area

Table 5:
Total above-ground (TAG) biomass and accessible biomass (mean ± standard error (SE ) kg ha-1) in different habitats during the two seasons

Table 6:
The net primary production (NPP), accessible production (mean ± SE as kg ha-1 y-1 mm-1) and rain use efficiency (RUE) of different habitats

However, some shrubs and sub-shrubs were active throughout the whole year. These species were more conservative in the use of their own resources, especially soil moisture and developed a root system that was capable of exploiting soil moisture and minerals from a large volume of soil and at depth that was permanently wet, which in-turn enabled them to extend their activities even under conditions of moisture stress Ayyad et al. (1983). This behaviur of plant species occurred in some species in the study area. This type of species played an important role in sustainable production of the natural forage of the pasture.

The study area can be divided into 5 habitats (Heneidy, 2002) according to soil type and soil characters: the rocky plateau, the flat plateau, the rocky ridge, the non-saline depression and the saline depression. (Noy-Meir, 1973) suggested that the bulk of primary standing biomass of the community in semi-arid regions was made up of woody life-forms. This means that accessible parts do not depend upon the primary above-ground phytomass, but depend upon the configuration and morphological shape of the species and their life-forms (Heneidy, 1992). Grevstad and Klepetka (1992) recorded that the production level of herbivores may depend more upon plant architecture than on the particular species of natural enemies present.

The annual average of the primary production in present study was 590 ± 117 kg ha-1 y-1, while the accessible production was 410 ± 39 kg ha-1 y-1, compared with that of the woody steeps in arid zones which ranged from 300 to 600 kg ha-1 y-1 (Le Houérou, 1972). On the other hand, the value obtained in the present study was less than that obtained by Abdel-Razik et al. (1988a) and Heneidy (1992) at Omayed in the coastal region (668 and 720 kg ha-1 respectively). However, the average of annual forage yield in the saline depression habitat in coastal region was 1560 kg ha-1 (Heneidy and Bidak 1996) which is three times higher than that value recorded in the present study.

The RUE factor is the quotient of annual primary production by annual rainfall. RUE decreased when aridity increased together with the rate of useful rains and as potential evapotranspiration increased. But it also strongly depends on soil condition and, more than anything, on vegetation condition particularly the dynamic status. It thus greatly relies on human and animal impact on the ecosystems. The RUE is a good indicator of ecosystem productivity (Le Houérou, 1984).

The average of accessible dry matter production per mm rainfall ranged from 1.4 to 7.5 kgha-1 y-1 in the habitats of flat plateau and the saline depression respectively. The average RUE was 5.1 kg ha-1 y-1 mm-1 for accessible production while for primary production was 10 kg ha-1 y-1 mm-1. In comparison, the average of the grazeable dry matter production per mm rainfall at Omayed area was 4.8 kg ha-1 y-1 (Abdel-Razik et al., 1988a) while that average of RUE was 10.4 kg ha-1 y-1 mm-1 at salt marshes in the coastal region (Heneidy and Bidak 1996). Actual RUE figures throughout the arid zones of the world may vary from less than 0.5 in depleted sub-deseric ecosystems to over 10 in highly productive and well managed stepped (Le Houérou, 1984).

Generally, the great variations in the productivity levels in different sites are due to the variations in soil, climate, vegetative types and grazing pressure. Consequently coefficient of variation (CV) was taken as 107.3 ± 9.2 mm in the saline depression habitat. Calculated CV of the primary production (1.2) indicated that there was a great variation between sites. This variation did not depend on rainfall and only may hide other factors as mentioned above (e.g. life-forms, soil condition, topography and human impact etc). This result agrees with those obtained by Le Houérou (1988) who assessed that variability in primary production does not depend only on rainfall, but also on ecosystem dynamics, soil surface condition and texture. For accessible production, CV is lower (e.g. slight variation between different sites and also in the relative variation in the amount of rainfall at different sites. The average of the primary, production and accessible production ± SE on one hand and RUE, carrying capacity (CC), Coefficient of Variation (CV), Production to Rain Variability Ratio (P/RVR) on the other hand, has been summarized below.

1 = Primary production (kgd.wt.ha-1 y-1) ± S.E
2 = Accessible production (kgd.wt.ha-1 y-1) ± S.E
3 = Rainfall (mm) ± S.E

The average of primary dry matter production was 590 ± 117. This figure does not include the amount eaten during the grazing season, which could increase the primary annual production. This would imply a maximum safe carrying capacity. Rain Use Efficiency for primary production and accessible part was 8.7 and 5.1 kg ha-1 y-1 mm-1 respectively. Carrying capacity ranged from 0.5 to 4.4 ha head-1 and the mean ± SE was 1.7 ± 0.17 ha head-1. The variability of annual production was 1.2 times that of the variability of annual precipitation. Production to Rain Variability Ratio (P/RVR) averages 2.4 world-wide in primary production than in accessible. Conversely, P/RVR increases when rainfall decreases and with ecosystem degradation. Finally natural vegetation is affected by rainfall variability in its composition, structures, morphology, ecophysiological adaptation and physiological processes. RUE decreases with rainfall and with the depletion status of the ecosystem (biomass, permanent ground cover, organic matter, microbial activity), (Le Houérou, 1988).

Linear correlation coefficient showed that there was highly inversely significant correlation (at 0.01 probability level) between accessible production and CC (r = -0.83**) and significant correlation (at 0.05 probability level) between accessible production and RUE (r = 0.45*).

The relatively high annual production of the range land under study as compared with the average production of North Africa (which varies between 200 ton ha-1 y-1) (Le Houérou, 1975 and Sarson and Salmon, 1977) may be attributed to the fact that its vegetation is composed mainly of perennials that can exploit moisture substantial at deep layers of the soil. It is represents a good production level if compared with the production level at Omayed area 80 km west of Alexandria (Heneidy, 1992). However, this area needs more studies and a good plan for improvement as rangeland within the carrying capacity of the ecosystem, for a sustainable development.


The author wish to thank to Professor El-Rayis, O. A. and Prof. M. S. Abdel-Razik for their careful revision of the manuscript. I would like to express my deep appreciation to Prof. F. Abdel-Khader, for facilitating during the field work.

1:  Abdel-Razik, M., M.A. Ayyad and S.Z. Heneidy, 1988. Preference of grazing mammals for forage species and their nutritive value in a Mediterranean desert ecosystem (Egypt). J. Arid Environ., 15: 297-300.

2:  Abdel-Razik, M., M.A. Ayyad and S.Z. Heneidy, 1988. Phytomass and mineral composition in range biomass of a Mediterranean arid ecosystem (Egypt). Ecol. Plant, 9: 359-370.

3:  Ayyad, M.A., 1978. A preliminary assessment of the effect of protection on the vegetation of the Mediterranean desert ecosystems. Tackholmia, 9: 85-101.

4:  Ayyad, M.A., M. Abdel-Razik and N. Ghali, 1983. On the phenology of desert species of Western Mediterranean coastal region of Egypt. Int. J. Ecol. Environ. Sci., 9: 169-183.

5:  Boulos, L., 1995. Flora of Egypt: Checklist. Al-Hadara Publishing, Cairo, Egypt, pp: 287.

6:  Grevstad, F.S. and B.W. Klepetka, 1992. The influence of plant architecture on the foraging efficiencies of a suite of ladybird beetle feeding on aphids. Oecologia, 92: 399-404.
CrossRef  |  

7:  Heneidy, S.Z., 1992. An Ecological Study of the Grazing Systems of Marist, Egypt. UNESCO, Paris, pp: 51.

8:  Heneidy, S.Z., 2002. Role of indicator range species as browsing forage and effective nutritive source, in Matruh area, a mediterranean coastal region, NW-Egypt. J. Biol. Sci., 2: 136-142.
CrossRef  |  Direct Link  |  

9:  Heneidy, S.Z. and L.M. Bidak, 1996. Halophytes as a forage source in the Western Mediterranean coastal region of Egypt. Desert Inst. Bull. Egypt, 2: 283-304.

10:  Heneidy, S.Z. and S.M. El-Darier, 1995. Some ecological and socio-economic aspects of Bedouins in Mariut rangelands, Egypt. J. Union Arab Biologists Bot. Cairo, 2: 121-136.

11:  Hodgkinson, K.C. and G.N. Harrington, 1985. The case for prescribed burning to control shrubs in eastern semi-arid woodlands. Aust. Rangeland J., 7: 64-74.

12:  Le Houerou, H.N., 1984. Rain Use Efficiency: A Unifying Concept in Arid-Land Ecology. Academic Press Inc., London, pp: 213-247.

13:  Le Houerou, H.N., 1993. Grazing Lands of the Mediterranean Basin. In: Natural grassland, Eastern Hemisphere and Resume: Ecosystem of the World, Corpland, R.T. (Ed.). Vol. 8, Elsevier Science Publisher, Amsterdam, pp: 171-196.

14:  Milner, C. and R. Hughes, 1970. Methods for the Management of Primary Production of Grassland. IBP Handbook, Moscow, pp: 70.

15:  Noy-Meir, I., 1973. Desert ecosystems: Environment and producers. Ann. Rev. Ecol. Syst., 4: 25-51.
CrossRef  |  Direct Link  |  

16:  Sarson, M. and P. Salmon, 1977. Eleuage, Paturage et donnees de bass pour un amenayment sylvo-pastural dans la Zone No. 2. MOR 73/016, Rabat FOA/MIN. Agric. Ref. Agric.

17:  Snedecor, G.W. and W.G. Cochran, 1968. Statistical Methods. 6th Edn., Iowa State University Press, Ames, IA., USA.

18:  Tackholm, V., 1974. Student's Flora of Egypt. Cairo University Press, Cairo, Egypt, Pages: 888.

19:  Tueller, P.T., 1988. Vegetation Applications for Rangeland Analysis and Management. Kluwer Academic Publisher, Dordercht, pp: 642.

20:  UNESCO., 1977. Map of the World Distribution of Arid Regions. MAB., Paris.

21:  Le Houerou, H.N., 1972. Continental Aspects of Shrubs Distribution Utilization and Potentils Africa the Mediterranean Region. In: Wildland Shrubs their Biology and Utilization, McKell, C.M., J.P.B. Blaisdell and J.P. Goodin (Eds.). USDA, UK.

22:  Le Houerou, H.N., 1975. The natural pastures of North Africa types productivity and development. Proceedings of the International Symposium on Range Survey and Mapping in Tropical Africa, Bamako. Addis Ababa, ILCA.

23:  Le Houerou, H.N., 1980. The Role of Browse in the Sahelian and Sudanian Zones. In: Browse in Africa, Le Houerou, H.N. (Ed.). ILCA, Addis Ababa, pp: 491.

24:  Le Houerou, H.N., 1988. Interannual variability of rainfall and its ecological and managerial consequences on natural vegetation crops and livestock. Proceedings of the 5th International on Mediterranean Ecosystems, July 15-21, IUBS., Paris, pp: 323-346.

25:  Moore, P.D. and S.B. Chapman, 1986. Methods in Plant Ecology. Blackwell Scientific Publications, Oxford, pp: 550.

©  2021 Science Alert. All Rights Reserved