Subscribe Now Subscribe Today
Research Article
 

Acacia nilotica and Medicago sativa, Suitable Plants for Agro-Forestry in Southern Coasts of Iran



Mohammad Hassan Emtehani and Masoud Tabari
 
Facebook Twitter Digg Reddit Linkedin StumbleUpon E-mail
ABSTRACT

Habitats of the multipurpose tree, Acacia nilotica, were identified along the coastline of the Persian Gulf and Oman Sea, south of Iran. Four sites were randomly chosen and in each one, vegetation as well as climatic and soil characteristics were studied. Likewise, biometry of Acacia trees was conducted and compared in the sites. The fodder values in leaf and fruit of Acacia were determined and compared with those of in foliage of Medicago sativa being managed under an agro-forestry system. By analyzing data it was revealed that the biggest trees were found in Dashteyari region and the smallest in Bamani region (both in the Oman Sea coast). Values in most of nutritional elements were higher in foliage of Medicago than in leaf and fruit of Acacia, respectively. From this investigation it is concluded that in south of Iran where the site is favorable for Acacia plantation, cultivation of Medicago or other adaptable crops together with Acacia can be developed as agro-forestry systems (such as undercropping and intercropping) if water is available.

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

 
  How to cite this article:

Mohammad Hassan Emtehani and Masoud Tabari, 2007. Acacia nilotica and Medicago sativa, Suitable Plants for Agro-Forestry in Southern Coasts of Iran . Pakistan Journal of Biological Sciences, 10: 1713-1717.

DOI: 10.3923/pjbs.2007.1713.1717

URL: https://scialert.net/abstract/?doi=pjbs.2007.1713.1717

INTRODUCTION

One of the main tenets of agro-forestry is that trees maintain soil fertility (Palm, 1995). Accumulation of organic matter and conservation of nutrients under trees in agro-forestry systems are well documented (Nair, 1993; Young, 1997; Pandey et al., 2000). The nutrients generated by trees can be ex-ploited within production system, either simultaneously, as in intercropping, or sequentially, as in rotational fallow systems (Rhoades, 1997). However, nutrients generated by trees generally do not support growth of intercrops in simultaneous system (Puri and Bangarwa, 1992; Pandey et al., 1999).

Acacia nilotica is a multipurpose tree (Pandey and Sharma, 2003). It is a leguminous species spreading, depending on site with other Acacia genus as A. ehrenbergiana, A. albida and genus of Prosopis, in southern coasts and islands of Iran (Persian Gulf and Oman Sea). It is a severely light demanding tree with circular large crown (Sabeti, 1984). The tree individuals in particular in and around villages are maintained by residents (Djavanshir, 1998). Its natural habitats often occur in floodway and the local where the periodical or seasonal floods are gathered (Emtehani, 1998). Its foliage is directly or indirectly used by livestock and the wood is favorable for building-ship industries and particularly for boat (Shah-Beygi, 1992). The tree is socially accepted because it provides fuel, fodder, gum and local medicine to farmers. Nitrogen fixing ability of the tree makes it one of the most preferred species for agricultural fields (Puri et al., 1994). Tree builds up nutrients under its canopy and forms islands of nutrients in the fields (Pandey et al., 2000). However, the understorey crops are unable to utilize these nutrients due to limited light (Pandey et al., 1999). To those reasons, in these regions some plantations of Acacia nilotica together with other crops are observed as various agro-forestry systems. One of the main common crops growing as undercropping with Acacia is Medicago sativa. Generally there is not any report showing the suitable suite for Acacia nilotica plantation and its incorporation with Medicago sativa in southern coasts of Iran and islands Persian Gulf and Oman Sea.

To this reason, in this research stations of Acacia nilotica together with Medicago sativa are studied in southern coasts of Iran. The inventory for growth of Acacia is the main objective of this study. This, in fact, can assign the best Acacia sites in the investigated regions and propose the most suitable sites for its plantation development in future. The other principal goal is to determine the fodder values for livestock by comparing nutritional values of Acacia and Medicago. It is hypothesized that the sites benefiting the Oman Sea climate may produce bigger Acacias. Likewise, foliage of Medicago has higher nutritional elements than that of Acacia.

MATERIALS AND METHODS

In order to carry out the research after identifying the Acacia nilotica habitats in 2003, four main stations with situations illustrated in Fig. 1 and the characteristics given in Table 1 were randomly chosen along the coastline of Persian Gulf and Oman Sea, south of Iran. The data collected from the nearest meteorological station, showing a warm xeric climate with precipitation of 125-200 mm/year and a mean minimum absolute temperature of 3-8°C (Table 1). The main tree and shrub species accompanying with Acacia nilotica were specified in each station (Table 2).

The soil chemical-physical properties were assigned by digging a profile in each site (Table 3). The soils were identified with moderate texture, non-acidic pH and limestone bed. Biometry of all trees and shrubs, including diameter at breast height (d.b.h.), height and crown diameter, was made by 100% sampling. Nutrient of leaf and fruit of Acacia in Bamani region was compared with foliage of Medicago sativa growing as undercropping with Acacias. Data was examined by one-way analysis of variance (ANOVA) and tested for significance at 95% confidence limits with Tukey-HSD and t-tests.


Table 1: Geographical situation and climatic census of the study sites in southern coasts of Iran

Fig. 1: Location of the investigation sites (showed in circular) in Persian Gulf and Oman Sea coasts, south of Iran (A = Chahemoslem, B = Gaspirkartan, C = Bamani and D = Dashteyari)

Table 2:

Main tree and shrub species accompanying with Acacia nilotica in southern coasts of Iran


Table 3: Soil properties of Acacia nilotica sites in southern coasts of Iran

RESULTS

In the four investigated sites the means of diameter at breast height (d.b.h.), height and crown diameter of Acacia trees were 27.2 cm, 8.3 m and 8.7 m, respectively (Table 4). The biggest d.b.h. (35.5 cm) allocated to Dashteyari and the smallest one (17.7 m) to Bamany. The greatest height (11 m) was recorded in Dashteyari and the shortest height was noted in Bamani. Crown diameter was biggest (11.3 m) in Gaspirkarten and shortest (6.5 m) in Bamani. Generally the biggest trees were found in Dashteyari and then in Gaspirkartan and the smallest in Bamani.

The amount of protein, lignin and ash, N, P, K and Mg was higher in foliage of Medicago than leaf and fruit of Acacia (Table 5). By contrast, amount of fat, NFE, TDN, Ca, Fe and Br was lower in foliage of Medicago than leaf and fruit of Acacia.


Table 4:

Biometry of Acacia nilotica trees in the experimental sites of southern coasts of Iran

-Means, followed by different letter(s) in column differ significantly (p<0.05) among sites, using Tukey's test


Table 5:

The comparison of nutrient values in leaf and fruit of Acacia and foliage of Medicago in Bamani (Oman Sea coast)

-Different letter(s) in row are significantly different (p<0.05), using Tukey's test, *Data is not accessible, ©Different letter(s) in row are significantly different (p<0.05), using t-test

However, most of the nutritional values for Acacia were greater in leaf than fruit. As a whole, no significant differences could be detected in Mg of leaf and fruit of Acacia and in Mn, Zn of leaf of Acacia and foliage of Medicago.

DISCUSSION

The results reveal that the Acacias growing in Dashteyari and Gaspirkartan benefit from a greater d.b.h. and height compared to other two sites. The Acacias of Bamani have the smallest d.b.h. and height among the investigated sites. Gaspirkartan produces the largest and Bamani the smallest crown diameter for this species. However the biggest trees are observed in Dashteyari and the smallest in Bamani, situated in Oman sea coast.

The values in nutrient elements are mostly higher in foliage of Medicago than leaf and fruit of Acacia. In Acacia it is often greater in leaf than fruit. Similarly, protein and TDN in leaf of Acacia is bigger than its fruit, showing a higher nutrient value for the leaf in comparison with the fruit. Likewise, compared to foliage of Medicago, the lower rate of ash and lignin in leaf is a positive value for Acacia. Generally, it can be confirmed that integration of Acacia and Medicago in the warm xeric plains of south of Iran increases biomass and nutrient of crops and the villagers' income, as well (Emtehani, 2003).

This is while that the best places in order to plantation development and agro-forestry practices may be mainly suggested for Dashteyari and then for Gaspirkartan in the Oman Sea coasts. It can be also declared that Acacia growth will be enhanced when cultivated as an agroforestry system along with Medicago, particularly in well-irrigated and manured fields (Djazirei, 1987, 2001). In reality, such a method will promote more closely nutrient cycling than only agricultural system (Sreemannarayana, 2003) applied with Medicago. This technique not only improves the rehabilitation of deforested areas but also solves the unemployment problems and progresses the cultural-economical-social conditions in the region (Agha-Zamani, 1987).

Regarding the above-mentioned, we found the biggest Acacias in Oman Sea coasts and high nutrient in leaf of Medicago in the investigated sites, however it is proposed that the sites suitable for Acacia nilotica, in south of Iran (particularly the southern coasts of country and islands of Persian Gulf and Oman Sea), where the environment is suitable from viewpoint of water and soil, cultivation of Acacia along with Medicago or other adaptable crops should be developed by different agro-forestry systems, including undercropping and intercropping. Of course such as old traditional practice, canopy management of the tree can not be followed by farmers but the trees can be cut and sell ≥ 12-year-old after completion of the rotation cycle. In reality, crop yields will increase when trees are cut or coppiced in agro-forestry system (Tilander et al., 1995; Szott et al., 1999).

REFERENCES
1:  Agha-Zamani, J., 1987. Review on afforestation and restoration of tropical forests in coastal band of South of Iran. Proceedings of the Symposium of the Restoration and Afforestation Development of the Coasts and Islands of the Persian Gulf and Oman Sea, Forests and Ranges Organization of Iran.

2:  Djazirei, M.H., 1987. Opinions about afforestation and restoration of the tropical forests in coastal band of South of Iran. Proceedings of the Symposium of the Restoration and Afforestation Development of the Coasts and Islands of the Persian Gulf and Oman Sea, Forests and Ranges Organization of Iran.

3:  Djavanshir, K., 1998. Vegetation of Bashagard Region. Tehran University Publishers, Tehran, Iran, pp: 364.

4:  Djazirei, M.H., 2001. Afforestation in Dry Regions. Tehran University Publishers, Tehran, Iran, pp: 450.

5:  Emtehani, M.H., 1998. Ecological study of the native leguminous trees and shrubs in south of Iran. Ph.D. Thesis. Islamic Liberal University of Tehran, pp: 490.

6:  Emtehani, M.H., 2003. Native Acacia Species in Iran. Yazd University Publishers, Iran, pp: 120.

7:  Nair, P.K.R., 1993. An Introduction to Agro-forestry. Kluwer Academic Publishers, Dordrecht, The Netherlands, pp: 499.

8:  Pandey, C.B., K.S. Pandya, D. Pandey and R.B. Sharma, 1999. Growth and productivity of rice (Oryza sativa) as affected by Acacia nilotica in a traditional agro-forestry system. Trop. Ecol., 40: 109-117.
Direct Link  |  

9:  Pandey, C.B., A.K. Singh and D.K. Sharma, 2000. Soil properties under Acacia nilotica trees in a traditional agro-forestry system in central India. Agrofor. Syst., 49: 53-61.
Direct Link  |  

10:  Pandey, C.B. and D.K. Sharma, 2003. Residual effect of nitrogen on rice productivity following tree removal of Acacia nilotica in a traditional agro-forestry system in central India. Agric. Ecosyst. Environ., 96: 133-139.
Direct Link  |  

11:  Puri, S. and K.S. Bangarwa, 1992. Effects of trees on the yield of irrigated wheat crop in semi arid regions. Agro-For. Syst., 20: 229-241.
Direct Link  |  

12:  Puri, S., S. Singh and A. Kumar, 1994. Growth and productivity of crops in association with an Acacia nilotica tree belt. J. Arid Environ., 27: 37-48.
Direct Link  |  

13:  Rhoades, C.C., 1996. Single-tree influence on soil properties in agroforestry: Lessons from natural forest and savanna ecosystems. Agro-For. Syst., 35: 71-94.
Direct Link  |  

14:  Sabeti, H., 1984. Forests, Trees and Shrubs of Iran. Yazd University Publishers, Iran, pp: 875.

15:  Shah-Beygi, B., 1992. Management and planning to improve the boat industry. Study of Boat Industry in Gheshm, Full Report of the Boat Industry in Southern Coasts and Islands of Iran. Free Region of Gheshm.

16:  Sreemannarayana, B., 2003. Role of Agro-forestry in Soil Fertility. In: Agro-forestry: Potentials and Opportunities, Pathak, P.S. and R. Newaj (Eds.). Agrobios (India) and Indian Society of Agroforestry, India, pp: 65-78..

17:  Szott, L.T., C.A. Palm and R.J. Buresh, 1999. Ecosystem fertility and fallow function in the humid and subhumid tropics. Agrofor. Syst., 47: 163-196.
CrossRef  |  Direct Link  |  

18:  Tilander, Y., G. Ouedraogo and F. Yougma, 1995. Impact of tree coppicing on tree-crop competition in parkland and alley farming systems in semiarid Burkina Faso. Agro-for. Syst., 30: 363-378.
Direct Link  |  

19:  Young, A., 1997. Agro-forestry for Soil Management. CAB International, Wallingford, UK.

20:  Palm, C.A., 1995. Contributions of Agroforestry trees to nutrient requirements of inter cropped plants. Agrofor. Syst., 30: 105-124.
CrossRef  |  Direct Link  |  

©  2021 Science Alert. All Rights Reserved