Study of pulse crops biodiversity in agroecosystems of Iran

Document Type : مقالات پژوهشی

Authors

Ferdowsi University of Mashhad

Abstract

Introduction
In recent years due to problems associated with intensive agricultural systems, the role of legumes in the sustainability of cropping systems has been accelerated (Draper, 2006). Currently, one of the challenges of energy intensive agricultural systems is monoculture, which is associated with low biological diversity (Carmine, 2007). Iran has been considered as the area with low agricultural diversity and dominance of few crops particularly cereals in the main cropping systems (Nassiri Mahallati et al., 2003). The most common index of plant diversity is the SHANNON index. In agroecosystems, a Shannon index of 3 is rare (Meng et al., 1999). Researchers evaluated agrobiodiversity of agricultural systems at species, variety and cropping systems in a comprehensive survey for Iran and they found that the diversity at all levels have been declining due to introduction of new agricultural technology (Koocheki et al., 2005). They found that for wheat and rice which are the main cereal crops with high variety richness the SHANNON index ranges from 1.5 to 1.7. The aim of present study was to evaluate biodiversity of pulse crops in Iran and the future trends of yield, acreage and production.
Materials and Methods
In this survey, the status of pulse crops in different provinces of the country from 1983 to 2003 was evaluated. These crops were bean (Phaseolus vulgaris), chickpea (Cicer arietinum) and lentil (Lense culinaris). Other species of this category were classified as other pulse crops. The SHANNON index (H) was calculated based on the cultivated area (Smale et al., 2003):
For evaluating of the trends in biodiversity, cultivated area, production and yield, time series were used by the following formula:
Yt = f (t) + et (1)
Where, Yt is the variable at the time of t, f(t) is a function which describes Y on the bases of time and et is the prediction error of the time of t. Prediction of trend was calculated by direct method (Patchet, 1982) and the first year of data was considered as starting point. In this study, based on the type of time series, double dynamic mean and WINTERS method were used for the future prediction. In the WINTERS method, prediction is made on the bases of harmonized mean from time series data, in such a way that the highest weight is given to the nearest data and the weight of data is decreased with aversions from the present time.
Results and Discussion
The diversity index under rainfed condition showed an increasing trend whereas the reverse is true for the diversity index under irrigated condition. The diversity index for the whole pulse crops (rainfed plus irrigated) was inconsistent, but an increasing trend was observed from 1983 to 2003 and a decreasing trend was observed afterwards. The decreasing trend was also true for the prediction towards the year 2021. Similar trend as for the period 1983 to 2003 is expected up to the year 2021.
The acreage and yield for irrigated has been increased for bean, whereas for chickpea, the rainfed acreage has been increased. The lentil was similar to chickpea. The acreage of the other pulse crops showed a slightly increasing trend from 1983 to 2003. This rise is due, in part, to an increase in the irrigated acreage. This trend is likely to increase slightly over the coming years and is likely it will show a consistent trend afterwards. The yield of other pulse crops decreased from 1983 to 2003. This reduction is due to a reduction under rainfed conditions. The yield of other pulse will decreased until 2021.
The same trend is shown for production. Although production of bean has shown an increase, this increase is mainly due to an increase under irrigated condition, whereas the rise in lentil and chickpea is due to rainfed production. The same trend is expected up to the year 2021 for these crops. The production of the other pulse crops showed a slight decreasing trend from 1983 to 2003. This decreasing is due to a decreasing under irrigated and rainfed conditions. The trend will show increase for a few time and it will show a consistent trend afterwards.
Only the yield for bean has an increasing trend and this is associated with this fact that bean has been under irrigated conditions. No increase is shown for other crops which are produced under rainfed condition. Therefore, it may be concluded that the production increase for bean is mainly due to yield and acreage increase, whereas for other pulse crops, the production increase is due to increasing in the acreage, because the yield showed somewhat the decreasing trend during these years. Prediction of diversity index of rainfed pulse crops up to the year 2021 indicates an increase of 1.22 folds compared to the year 2003. However diversity index for irrigated and irrigated plus rainfed showed a reduction of 0.88 and 0.9 folds, respectively. The magnitude of the change of production, yield and acreage for different pulse crops is shown. It is apparent that the prediction of production for the bean up to the year 2021, under rainfed, irrigated and rainfed plus irrigated will be increased by 2.96, 1.60 and 1.95 folds compared with the year 2003. These values for the yield of bean under similar conditions are 1.59, 1.03 and 1.22 folds, respectively and also for the acreage will be 1.88, 1.58 and 1.59 folds, respectively.
Acreage for the chickpea and lentil for rainfed, irrigated and irrigated plus rainfed will be 2.47, 0.37, 2.41 and 2.63, 1.31, 2.54 folds, respectively. These values for other pulse crops will be 4.96, 1.49 and 2.01 folds, respectively. An increasing trend of the yield has been reported for the future for different crops (Khush, 1999; Rosegrant et al., 2001). Borlog (2000) has stated that yield growth which is associated with genetic improvement and the use of chemical fertilizers, pesticides and irrigation systems, will be continued, in the future.
We can predict that the rate of acreage and production of pulse crops in Iran, specially three important crops, bean, chickpea and lentil will increase until 2021. However, under rainfed conditions, it is likely that the yields, particularly of chickpea and lentil will stabilize.
Conclusions
This study was conducted to evaluate the trends in biodiversity, cultivated area, production and yield of pulse crops in different provinces of Iran from 1983 to 2003. Time series formula was used for such evaluation. The diversity indices studied under irrigated and rainfed conditions. It seems the results can be useful for policy makers, scientists and food industry to improve food security in country.

Keywords


1. Bagheri, A., Nezami, A., and Porsa, H. 2005. Analysis on approaches of pulse crop research in Iran. Approaches of the First National Symposium of Pulses Crop. Agricultural Researches Magazine of Iran 4(1): 1-13. (In Persian).
2. Bagheri, A., Nezami, A., and Soltani, M. 2000. Improvement of cool season pulse crops for tolerance against stresses. Agriculture Education and General Researches Organization Press, 445 p. (In Persian).
3. Bell, M.A., and Fischer, R.A. 1994. Using yield prediction models to assess yield gains- a study for wheat. Field Crops Research 36: 161-166.
4. Blackmore, B.S., and Godwin, R. 2003. The analysis of spatial and temporal trends in yield map data over six years. Biosystems Engineering 84: 455-466.
5. Borlaug, N.E. 2000. Ending world hunger; the promise of biotechnology and the threat of antiscience zealotry. Plant Physiology 124: 487-490.
6. Carmine, C., Curci, M., Pellegrino, A., Ricciuti, P., Tursi, N., and Ruggiero, P. 2007. Soil microbial dynamics and genetic diversity in soil under monoculture wheat grown in different long-term management systems. Soil Biology and Biochemistry 39(6): 1391-1400.
7. Draper, P. 2006. Cool Season Pulse Crops Suitable for Rotation with Rice. Australian Nuffield Farming Scholars Association, Sponsored by RIRDC.
8. ESA, 1997. Human Alteration of the Global Nitrogen Cycle: Causes and Consequences. Issues in Ecology, No 1.
9. FAO, 1994. Production Yearbooks on Agriculture. Statistical Series 125. (48) Rome, Italy.
10. FAO, 2013. FAO Production Year Book (58). Rome, Italy.
11. FAO, 2013. Pulse: past trends and future prospects. In: Food Legumes for Nutritional Security and Sustainable Agriculture. 4th International Food Legumes Research Conference (IFLRC-IV). 18-22 October. New Delhi, India.
12. Hanke, J.E., and Reitsch, A.G. 1995. Business Forecasting. Prentice Hall, Englewood Cliffs.
13. Khush, G.S. 1999. Green revolution: preparing for the 21st century. Genome 42: 646-655.
14. Koocheki, A. 2006. Agrobiodiversity of field crops in Iran. Collection of Articles on Science, Agriculture, Veterinary, Engineering, Name-Ye Farhangestan-e Olom, Iran. (In Persian).
15. Koocheki, A., Nassiri Mahallati, M., Jahanbin, M., and Zarea, A. 2005. Crop varieties diversity of Iran. Biaban 9(1): 49-66.
16. Meng, E.C., Smal, M., Rozelle, S., Ruifa, H., and Huang, J. 1999. The cost of wheat diversity in China. American Agricultural Economics Association Annual Meeting, August 8-11, Nashvilsle, Tennessee.
17. Monti, A., and Venturi, G. 2003. Comparison of the energy performance of fiber sorghum, sweet sorghum and wheat monocultures in northern Italy. European Journal of Agronomy 19(1): 35-43.
18. Murgan, A.E. 1988. Ecological Diversity and its Measurement. London: Co room Helm.
19. Nassiri Mahallati, M., Koocheki, A., and Mazaheri, D. 2003. Crop species diversity of Iran. Biaban 10(1): 32-50.
20. Nezami, A., Bagheri, A., Kafi, M., Mahmoodi, A., and Khodadadi, A. 2005. Evaluation of legumes cultivation as fallow substitution crop in area of rainfed wheat in north Khorasan. Agricultural Science and Industries 19(1): 191-204.
21. Patchet, S.I. 1982. Statistical Methods for Managers and Administrators. Van Nostrand Reinhold Company, New York.
22. Rosegrant, M., Paisner, M., Meijer, S., and Witcover, J. 2001. Global food projections to 2020: emerging trends and alternative future. International Food Policy Research Institute, Washington, D.C.
23. Saxena, M.C. 1993. The challenge of developing biotic and abiotic stress resistance in cool season food legumes. In: K.B. Singh and M.C. Saxena (Eds.). Breeding for Stress Tolerance in Cool-Season Legumes. John Wiley & Sons, New York, p. 3-14.
24. Smale, E.M., Brennan, J.P., and Hu, R. 2003. Determinants of spatial diversity in modern wheat: examples from Australia and China. Agricultural Economics 28: 13-26.
25. Stocking, M. 2001. Agrodiversity: A positive means of addressing land degradation and sustainable rural livelihoods. In: A.J. Conacher and D. Kluwer (Eds.). Land Degradation. Academic Publishers, p: 1-16.
26. Swift, M.J., and Anderson, J.M. 1993. Biodiversity and ecosystem function in agroecosystems. In: E. Schultze and H.A. Mooney (Eds.). Biodiversity and Ecosystem Function. Springer, New York, p. 57-83.
27. Tilman, D. 1987. Secondary succession and the pattern of plant dominance along experimental nitrogen gradients. Ecological Monographs 57: 189-214.
28. Walker, G.K. 1989. Model for operational forecasting of western Canada wheat yield. Agricultural & Forest Meteorology 44: 339-351.
CAPTCHA Image