Influence Of Slope Aspects On Woodland Ecosystem Of Duhok - Dissertation Example

Influence of Slope Aspects on Soil and Vegetation Properties in Woodland Ecosystem of Duhok (Northern Iraq) Tutor Date Environmental conditions such as climatic conditions and landscape features that include position, gradient, topography and evolution, parent material and vegetation of any area affect its microclimate by altering the relative humidity, temperature and precipitation patterns of the area which are key in influencing the microbial activities of the soil, which determine the quality of organic content in the soils. (Tsui, Chen and Hsieh 2004, p.138). Studies have shown that position of a slope in an ecosystem affect the quality of organic material, soil chemistry and nutrient cycling, largely; it affects the soil quality than even the type of bedrock beneath the soil (Yimer, Sting and Adelkadir 2006, p.95). Research that has been conducted on influence of topographical features on soils in southern Italy clearly demonstrate that soils originating from the same parent material, with the same vegetative covering and climate, with the only difference being the position of the landscape produced different and varied micro climatic conditions (Chen, Hsieh, Jiang, Hsieh and Sun 1997, p.230). In the northern temperate climatic zone, the aspect of a slope was found to be a huge influencer of the microclimatic conditions of the area mainly influenced by the temperature levels (Coleman, Crossley and Hendrix 2004, p.312). This is because the amount of solar that an area experiences will determine the levels of temperature and water in the soil, the inherent characteristics of the soil will be affected (Fu, Liu, Ma and Zhu 2004, p.48). In the Pinus laricio forests of southern Italy, the north-facing slope receives higher insolation and as a result, there is low moisture content that is also connected to the scanty vegetative cover and insolating effects of small vegetation (Gong, Chen, Fu and Wei 2007, p.1). Differences in the soil microbial activities, differ with different type of plant species. These plant species depend on the soil moisture, root activities, temperature and organic matter that return to the soil through the litter that falls from the plants (Gong, Brueck, Giese, Zhang, Sattelmacher and Lin 2008, p.484). Studies have been carried out to determine the effects of climatic conditions on the soil and vegetation properties, however no studies have been carried to determine the influence of aspect in the soil and vegetation properties(Tewksbury and Lloyd 2001, p.426). Soils in the forest are an important source of nutrients and minerals for the plants including nitrogen, sodium, potassium, magnesium and phosphorous and in some instances even soil acidity influence the type of vegetation that is found in a certain place (Bennie, Hill, Baxter and Huntley 2006, p.359). Studies conducted in the lowland rainforest of Taiwan showed that the soil types greatly affected the type of vegetation that was growing there. Research on redundancy of soil on depth of 0-5cm ad 5-15 centimetres showed different characteristics on each of the sample site with the Monte Carlo test showing that there were huge variations in the soil properties such as pH and exchangeable calcium. These were significantly related to the aspect and slope position of the area where each study was collected (De Bello, Lepš and Sebastià 2006, p.802) In the south Italy pinus forest, it was found that the microbial activities was 3 times higher in the south facing slopes as compared to the north facing slopes, which indicated a certain simulating factor that was present in the south facing slope and lacking in the north facing slopes. These differences were maintained thought the year (Gonga, Brueck, Giese, Zhang, Sattelmacher and Lin 2008, p.486). In the Mediterranean, a research conducted to determine the influence of various environmental factors on the plant association pattern found out that the south facing slopes had a less diverse plant species as compared to the slope side that was facing the polar side, which had a wide variety of the plants (Badano, Cavieres, Molina-Montenegro and Quiroz 2005, p.100). Most of the plants species that were on the northern facing slope were those with drought resistant characteristics and this was attributed to the competition for light (Smith 2010, p.193). In Boise Idaho USA, a study to determine aspect influences on the water storage and retention capacity found that plants in the northern facing slope were also found to store more water. This was mainly due to the filtration of the small particles of silt, which was more concentrated on that side as the decaying of the bedrock was also quicker in that area (Rech, Reeces and Hendricks 2001, p.59). The porosity and density of the soils were higher on the northern facing slopes, this was attributed to the vegetation that was found on the polar facing slopes which was much diverse and had quality litter. The decomposition rate of the litter from the plants was relatively high compared to the southern facing slopes (Sharma, Suyal, Ghildiyal and Gairola 2010, p.80). Justification A lot of research has been conducted on the influences of various climatic and environmental factors on the type of vegetation and the type of soils found in certain areas of this region and the influence of pH, soil density, moisture content, soil texture, EC, calcium carbonate and nitrogen. However, there exists very scanty data of the influence of aspect of a slope on the soil properties and the type of vegetation that is found in a certain area, this therefore has necessitated an intensive study of the various environmental factors that affect the vegetation type and soil type in this area. No research has been done of the effects of the aspect of a slope has on properties of soil and vegetation in Duhok (northern Iraq) and this research will open up the area for further research which has been neglected by researcher. The climate around the areas of Duhok is mainly semi arid therefore not many types of vegetation grow there, conducting this research will help in understand the special features that the vegetation and soils in this area posses in relation to which side of a slope they are located that makes them adapted to the zone. In essence this will enable the environmental authorities in Iraq be able to plan appropriately and increase the vegetation cover of the area with suitable species based on aspect in order to avoid the environmental disasters that come with the reduction in vegetation cover (Allen and Schlesinger 2004, p.586). References Allen, A.S and Schlesinger, W.H. 2004 Nutrient limitations to soil microbial biomass and activity in loblolly pine forests, Soil Biol. Biochem. 36, p.581–589. Badano, E. I., Cavieres, L. A., Molina-Montenegro, M. A. and Quiroz, C. L. 2005 Slope aspect influences plant association patterns in the Mediterranean matorral of central Chile. J. Arid Environ 62, p.93–108. Bennie, J., Hill, M., Baxter, R. and Huntley, B. 2006 Influence of slope and aspect on long-term vegetation change in British chalk grasslands. J. Ecol.; 94, pp. 355–368. Chen, Z.S, Hsieh C.F, Jiang, F.Y, Hsieh, T.H and Sun, I.F. 1997.Relationships of soil properties to topography and vegetation in a subtropical rain forest in southern Taiwan. Plant Ecol. 132, p.229–241. Coleman, D.A, Crossley, D.A Jr and Hendrix, P.F. 2004. Fundamentals of soil ecology. 2nd ed. Burlington (MA): Elsevier. P.311–318. De Bello, F., Lepš, J. and Sebastià, M. T. 2006 Variations in species and functional plant diversity along climatic and grazing gradients. Ecography 29, p.801–810. Fu B.J, Liu S.L, Ma K.M and Zhu Y.G. 2004. Relationship between soils characteristics, topography and plant diversity in a heterogeneous deciduous broad-leaved forest near Beijing, China. Plant Soil. 261, p.47–54. Gong J, Chen LD, Fu BJ and Wei, W. 2007. 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