عنوان مقاله [English]
Harvesting of self-growing plants, like acanthus; from the down slopes of mountainous regions often causes disturbances to the appearance of the slopes if it is mowed intensively.
These soil disturbances often occur with spring showers that accelerate soil erosion. On the other hand, the harvesting is inevitable because of acanthus clinical and sustenance uses and earning a livelihood for many local people who make a living with such crop in the harvesting seasons. So, as the spring season starts, the harvest of self growing plants becomes a usual phenomenon on the slopes in lower altitudes. The harvest of rooting plants as acanthus is in a way that makes pits on the ground and this may be agent of erosion when spring rain falls; specially, precipitation contact with plant germination in Iran. So, in this study, it has been tried to elucidate if the harvesting of acanthus makes erosion at every situation or reaching to erosion threshold needs to increase number of the harvesting in area unit as well as other location with more gradient and other characteristics.
In this survey has been taken into consideration the sediment producing in 16 plots with and without acanthus in the Viece Mountain, near Kermanshah city. Whereas, gradients and orientation are factors that play roles on erosion, in this research too, others aims purpose to study roles of acanthus harvesting on the different gradients and orientations on erosion acceleration. In this reason, these plots established on the four different slopes and two different aspects. The amount of sediment has been measured from plots in 9 time precipitation when it falls on late winter and early spring in 2007. Factor analyze and two ways ANOVA were the techniques that used for data analyzing.
Discussion and Results
A Max. shower including 46.8 mm produced 5.8 L. runoff and 0.69 g/m2 sediment on a slope with 40% gradient and a Min. rainfall with 1.4 mm precipitation set in motion only 0.175L runoff and 0.00153 g/m2 sediment from control plots on 15% slope.
Threshold of Acanthus Harvesting to Sediment Produce
Two ways ANOVAon obtained data shows that there is a significant difference between rainfall, slopes, aspects and erosion, that is, erosion have been deference on variety of showers, slopes and aspects. So, these results show that data have correctly been collected.
Using Factor Analysis method show that despite of a significant difference in the sediment producing on the different rainfall, gradient and precipitation times, there aren’t any significant difference of sediment producing between plots with and without acanthus plants(F1,71=0.944, P>0.05). The statistical analysis continued and limited to only days when harvesting occur. It illustrated that erosion don’t occur when acanthus harvesting become 2 - 4 per m2 as Kermanshah region, but erosion may be get a significant level on regions where more harvesting acanthus occur.
This study is carried out at a region where slopes were not acute and the number of acanthus at area unit were less, whereas, there are a lot of regions at Kermanshah province and even other neighbor provinces where slopes are more acute and acanthus grow up more per unit area . So, harvesting from these regions may increase probability of erosion occurrence as the results of this study show that the amount of significant level goes up when the study is limited to only harvesting times.
Keywords: Acanthus, Sediment yield, Erosion, Kermanshah.
1. Ahmadian S.H., Safaie M. and Jafari B (2005). Comparison soil erosion at dry farm, abounded dry farms, pasture and forest areas of Kasilan catchment – Mazadaran, Proceedings of 3rd Erosion and Sediment National Conference, Soil Conservation and Watershed Management Research Center.
2. Ateraf H., Telveri A (2005). The study of vegetation cover and cattle grazing management on soil erosion at losses pasture in Meraveh-Tepeh, Proceedings of 3rd Erosion and Sediment National Conference, Soil Conservation and Watershed Management Research Center.
3. Ayed, G. M, Adam, M. A (2010). The impact of vegetative cover type on runoff and soil erosion under different land uses, Catena, 81.
4. Gaskin,S and Rtta, G (2001). The role of cryptogams in runoff and erosion control on Bariland in the Nepal hill of the southern Himalaya ; Earth Surface Processes and Landforms; Vol 26.
5. Ghodoosi J., Tavekoli M., Khelkhali S. A., Soltani M. J (2006). Assessing effect of rangeland exclusion on control and reduction of soil erosion rate and sediment yield, Pajouhesh & Sazandegi , No 73.
6. Isabirye M. ,Ruysschaert G., Van linden L., Poesen J. ,Magunda M.K. , Deckers J (2006). Soil losses due to cassava and sweet potato harvesting:A case study from low input traditional agriculture, Soil & Tillage Research, 92.
7. Jabbari I (2006). Statistical Methods in Environmental and Geographical sciences, Publication of Razi University, 2nd Edition.
8. Kosmos, C, Gdanalatos, N. and Gerontidis, G (2000). Effect of land parameters on vegetation performance and degree of erosion under Mediterranean condition; Catena; Vol. 40.
9. Lo´pez-Berm´udez F., Romero-D´ıaz A, Mart´ınez-Fernandez J. and Mart´ınez-Fernandez J, (1998). Vegetation and soil erosion under a semi-arid Mediterranean climate: a case study from Murcia (spain) , Geomorphology, Vol 24.
10. Nunes , A. N., A.C. D, Almeida , C.A, Coelho (2011). Impacts of land use and cover type on runoff and soil erosion in a marginal area of Portugal, Applied Geography, 31.
11. Okhovet, M. H (2001). We come to Know Acanthus well, Damdar, 92.
12. Pour Nesrollah M.R., Alidoust M (2005). The study on provender plantation effect on decrease of runoff and soil conservation in country of Roodser, Proceedings of 3rd Erosion and Sediment National Conference, Soil Conservation and Watershed Management Research Center.
13. Rahmati, Arabkhedri M., Ardekani J, Khlkhali A (2004). The effect of grazing rate and slope on runoff and soil loss, Pajouhesh & Sazandegi.
14. Refahi H (1998).Water erosion and conservation, Tehran university publication, Second edition.
15. Ruysschaert G., Poesen J. , Notebaert B., Verstraeten G., Govers G (2008). Spatial and long-term variability of soil loss due to crop harvesting and the importance relative to water erosion: A case study from Belgium, Ecosystems and Environment, 126.
16. Ruysschaert G., Poesen J., Verstraeten G., Govers G (2004). Soil loss due to crop harvesting: significance and determining factors. Prog. Phys.Geogr. 28 (4).
Ruysschaert G., Poesen J. , Verstraeten G., Govers G (2006). Soil losses due to mechanized potato harvesting, Soil & Tillage Research , 86.
18. Sadeghi H. R., Raesian R. and Razevi S. L (2005). The comparison of runoff and sediment producing on abounded plantation and poor pastures, Proceedings of 3rd Erosion and Sediment National Conference, Soil Conservation and Watershed Management Research Center.
19. Sokooti, R., Ghaemian N., Jeferi A. and Ahmedi A(2005). The study of postural lands changing to dry farm on erosion and sediment producing, Proceedings of 3rd Erosion and Sediment National Conference, Soil Conservation and Watershed Management Research Center.
20. Stot,T. , Leeks G., Marks, S. and Sawyer, A (2001). Environmentally sensitive plot-scale timber harvesting: impacts on suspended sediment, bed load and bank erosion dynamics, Journal of Environmental Management.
21. Tavekoli M., Mohemedi y., Piri A (2005). The effect of pasturing plans on prevention of soil erosion in Eilam province. Proceedings of 3rd Erosion and Sediment National Conference, Soil Conservation and Watershed Management Research Center.
22. Zergeri, A., Medical plants (1999). Tehran university publication, 5th edition, 3rd Volume.