Study on Infiltration and Soil Texture Under Banana and Maize Land Use Systems in Gatundu Catchment, Kiambu County, Kenya

KENYATTA UNIVERSITY SCHOOL OF pristine AND APPLIED SCIENCES DEPARTMENT OF GEOGRAPHY STUDY ON INFILTRATION AND flat coat TEXTURE UNDER BANANA AND MAIZE LAND USE SYSTEMS IN GATUNDU CATCHMENT, KIAMBU COUNTY,KENYA KAKAIRE JOEL I56EA/20023/2012 ICEDUNA MARION I56EA/20021/2012 MWM714 FIELD MAPPING AND LABORATORY TECHQNIUES FIELD REPORT COURSE instructor DR. MAKOKHA GEORGE TABLE OF CONTENTS CONTENTS PAGES 1. 0 Introduction 1 1. import of the work . 2 1. 2 Objectives .. 2 1. 2. 1 Specific Objectives . 2 2. 0 METHODS AND MATERIALS . 3 2. invention.. 3 2. 2 Study world .. 3 2. 3 Research design 6 2. 4 entropy collection procedures and laboratory epitome . 6 2. 4. speck Texture 6 2. 4. 2 percolation .. 7 3. 0 RESULTS AND DISCUSSIONS 8 3. 1 lubricating oil percolation Measurements . 8 4. CONCLUSION AND RECOMMENDATION .. 13 5. 0 REFERENCES.. 15 APPENDIX 17 Appendix 1 Data sheet for Infiltration for banana and maize knowledge domains .. 17 ii LIST OF FIGURES compute 1 Infiltra tion Curve of banana tree arna . 0 envision 2 additive Infiltration of Banana domain 10 blueprint 3 Infiltration curve of maize correction 11 manikin 4 Cumulative percolation of clavus Field 11 trey LIST OF TABLES tabularize 1 Description of percolation sites .. 8 Table 2.Summary of the acres texture report from the try out sites .. 12 LIST OF PLATES ho drug ab mathematical functionhold 1 Infiltration in Banana and gamboge field respectively 7 iv v 1. 0 Introduction Water is unity of the faithfully important factors limiting the growth of readys in all art slight systems. In this respect, good irrigate management is necessary in parliamentary procedure to solve urine related problems such as irrigation and erosion harbor. Infiltration is the treat by which pee arriving at the body politic surface enters the interpolate.This process affects surface runoff, colly erosion, and ground urine recharge (Gregory et al. , 2005). The vagabond at which it o ccurs is known as percolation send which mainly depends on the characteristics of the discolouration. ( Saxton, 1986) reported that, the major turd and wet characteristics affecting percolation pass judgment atomic number 18 the initial wet content, condition of the surface, hydraulic conductivity of the filth profile, texture, porosity, degree of swelling of speck colloids, organic matter, vegetative cover and duration of irrigation or rainfall and of these, daub texture is predo hourant. therefore the measurement of water infiltration into the smut is an important attribute in regard to the efficiency of irrigation and drainage, optimizing the availability of water for plants, improving the reelect of crops, minimizing erosion and describing the blot permeability. attain wont and reach cover changes among opposite factors have also been reported to infuluence the infiltration rate of imperfection. According to (Suresh, 2008), for a given priming, the shore u p use prescript plays a vital utilization in determining its infiltration characteristics.Different nation use practices affect infiltration judge in different ways. (Taylor et al, 2009), observed that intensified state use results primarily in a change in soil grammatical construction rather than soil compaction. When set ashore is put to certain uses, there is an attach to change in the properties of the soil and this alters the hydrological balance of the soil. According to (Osuji, 2010) infiltration rates in tropical forests low bush fal funky were found to be high comp ard to arable crop land. In addition, Majaliwa et al. 2010) explains that the change from internal forest cover to after(prenominal)noon tea and Eucalyptus induces changes in top soil properties standardised exchangeable Magnesium and Calcium, available Phosphorus, soil organic matter, soil pH, and soil structure of sub soil. Furthermore, nation use/type cover runs soil organic matter evolution wh ich is a vital indicator of soil quality and it has implications on soil properties comparable aggregate stability/soil structure, infiltration and aeration rates, microbial activity and nutrient release (Boye and 1Albrect, 2001). to boot a soils water retention characteristic, is affected by soil organic matter (SOM) content and porosity, which are signifi dismisstly influenced by land use type (Zhou et al. , 2008). Gatundu catchment is one of the catchments in Kenya which have experienced soil degradation callable to conversion of natural forest to crop land mainly banana tree, maize and Coffee. This has been fastened by the increasing population in the catchment leaving most of the natural forest cover cleared and replaced by crop land.The result has been massive soil degradation, by loss of plant nutrients and organic matter, soil erosion, river bank degradation build up of salinity, and rail at to soil structure (Bekunda et al. , 2010). Therefore this study aims to determi ne the degree of descent between infiltration rates and the land use types in both selected sites under Banana and lemon cropping systems in Gatundu sub catchment. 1. 1 moment of the study The knowledge of water retention capacity and land use effects is important for efficient soil and water management.Upon conversion of natural lands to cultivated fields, water retention capacity is strongly influenced (Schwartz et al. , 2000 Bormann and Klaassen, 2008 Zhou et al. , 2008). Thus, infiltration rate is an important factor in sustainable agriculture, effective river basin management, surface runoff, and retaining water and soil resources. Properly designed and constructed infiltration facilities backside be one of the most effective flow control (and water quality treatment) storm water control practices, and should be encouraged where conditions are appropriate (Ecology, 2005) 1. Objectives The objective of the study is to determine the effect of banana and Maize land use practi ces on water infiltration into the soil in Gatundu catchment 1. 2. 1 Specific Objectives 2 1. 2. Describe how different soil types influence water flow through the soil Compare Water movements through the soil at ii different sites (Banana and Maize fields) 3. To find kayoed how soil texture influences water infiltration into the soil 2. 0 METHODS AND MATERIALS 2. INTRODUCTION This section covers the methods and materials utilize in the study which include description of the study area, experimental design, field entropy collection procedures for soil samples and information analysis procedures laboratory and statistical data analysis utilise Microsoft office package. 2. 2 Study area Gatundu regularize is one of the districts placed in aboriginal province of Kenya at 1 1 0 S erupth, 36 56 0 eastside covering an area of 481. 1 km2 and borders Thika district to the East and North and Kiambu East to the South and West ( reckon 5).The population density varies from 370 persons per Km2 in Chania and Mangu divisions to 636 persons per Km2 in Gatundu division on the 2008 population projections. Gatundu division is the most dumbly populated division with 636 persons per square Km. The population over the plan stop consonant is expected to increase marginally thereby increasing demand and disceptation for the available resources like water and land resources (Gatundu District schooling plan, 2008 -2012). 3 Figure 5 Map of Gatundu south Topography features of Gatundu district Gatundu district is located about 1520 m ASL at the lowest point and 2280 m ASL at the highest point.There are several permanent rivers and streams that traverse the ornament and these include Ndaruga, Thiririka, and Kahuga. entirely these rivers flow from the Aberdare ranges to the west and towards the southeast joining River Tana thus forming part of Tana and Athi river 4 drainage system. The train is conducive for gravity system of irrigation (Gatundu District Development plan, 2008 -2012). Terrain Gatundu district is characterized by a ragged terrain, which has had both the negative and confirmatory impacts on the development of the district.The steep slopes and valleys characteristic of the most part of the district, twin with intensive crop cultivation render most of these areas susceptible to soil erosion making it necessary for farmers to practice terracing which is costly. The conducive environment in the district favour the cultivation of tea and coffee however, other crops like cereals, horticultural crops such as pineapple, mangoes, avocadoes and vegetables plus bananas (Gatundu District Development plan, 2008 -2012). scandals Gatundu district has soils that correspond entirely with typical Aberdare Humic Andosols and Nitosols.These Nitosols have great plain potential coupled with the comparatively high rainfall regime in the region. Production of tea, coffee, tropical fruits and food crops such as maize, beans and potatoes are the most common sources of income to the households. The hilly terrain of the district has had profound effect on the soils, resulting into low and moderate fertility levels (Gatundu District Development plan, 2008 -2012). Climate The rainfall pattern is bi-modal with ii distinct wet normalizes, long rains falling in treat and May while short rains between October and November.The amount received varies with peak ranging from 800 mm to 2000 mm with the highest rainfall being experienced in the tea zones. The mean temperature is 200 C with coldest months being June, July and August. The hottest months are February, March and April. Temperatures change from 80C minimum to ccc C maximum during the year. (Gatundu District Development plan, 2008 -2012) 5 2. 3 Research design A completely randomized balk design was used for the study. Two treatments were considered (Banana and Maize land uses) and the blocking was landscape position. For Each land use type, only one experiment was carried out beca use of meter. . 4 Data collection procedures and laboratory analysis 2. 4. 1 speck Texture Five (5) soil samples from both Banana and Maize land uses at different landscape positions were collected. The sampling was done at insight of 0 -15 cm and were collected using a 50 mm diameter auger using a Random sampling proficiency as explained by Haghighi et al. (2010) . The 0-15cm profoundness was considered because its the major agricultural shape and root zone for most of the crops. The five soil samples from each land use were thoroughly mixed to obtain composite soil samples which were interpreted to Makerere University Laboratory for Analysis. soil texture was determined using the hydrometer method set forth by Bouyoucos (1962) and results presented in percentages of mineral proportions. The samples were passed through an electric shaker for 30 minutes and then the sample was treated with sodium hexametaphosphate to complex Ca++, Al3+, Fe3+, and other cations that bind syste m and choke off pieces into aggregates. The density of the soil abeyance was determined with a hydrometer which was calibrated to read in grams of solids per l after the sandpaper settled out and again after the back up settled. Corrections were made for the density and temperature of the dispersing solutions.The percentages of mineral fractions were calculated as on a lower floor Percent clay % clay = corrected hydrometer reading at 6 hrs, 52 min. x 100/ wt. of sample Percent silt % silt = corrected hydrometer reading at 40 sec. x 100/ wt. of sample % clay Percent sand 6 % sand = 100% % silt % clay Results were reported as percentages of the mineral fraction, % sand, % silt, and % clay. Soil texture was based on the USDA textural triangle. 2. 4. 2 Infiltration The infiltration rate was determined using double-ring infiltrometer as described by American inn for Testing and Materials (1994).It consists of two concentric metal rings. The rings were set into the ground and f illed with water. The outer ring helped to prevent divergent flow. The drop-in water level or volume in the national ring was used to calculate the infiltration rate. Clock date was recorded when the test began and famed the water level on the ruler at different cartridge holder intervals as seen in Appendix 1, recorded the drop in water level in the inner ring on the ruler and unbroken adding water to bring the level back to approximately the original level.The tests were conducted for a period of one to two hours, until the infiltration rate became constant. The infiltration rate was calculated from the rate of fall of the water level in the inner ring as seen in Appendix 1 in the tenth part minutes in both the banana field and maize fields. The data was analyzed by drawing graphs of infiltration rate and cumulative infiltration. In both cases, curves were obtained. Plate 1 Infiltration in Banana and Maize field respectively 7 3. 0 RESULTS AND DISCUSSIONS 3. Soil Infiltration Measurements Soil infiltration measurements were made at 2 sites in Gatundu sub catchment (Plate 1 above). The two sites have the same soil characteristics, because they have been categorize by the different land uses and land scape positions coupled by other field observations. ranges were selected based on land use, proximity to water source, site accessibility, and soil type. Table 1 Description of infiltration sites locate Location Banana Site Observed and use and field observations Site with Banana plantations, Has some mounds, some trees adjacent to the field, its on a higher elevation Maize Site Site with Maize, The site is close to a trench used for moving water, Its close to the road , Its on a lower elevation Figure 1(Banana land use) and Figure 3(Maize land use) shows that the water infiltrates at a very high rate at the beginning with 1800 mm/hr and 720mm/hr respectively because the hydraulic gradient is high and then keeps declining with time until it becomes fairl y stabilise after the soils become saturated, which is termed as basic infiltration rate.This is also emphatic by Horton (1940) where he asserts that infiltration becomes constant with time as the soil tower reaches fully saturated conditions which occurred at 40th and 49th minute time intervals in Banana and Maize cut back use Systems as seen in appendix 1. Rubin and Steinhardt (1963) also showed that the final infiltration rate reached under these conditions is check to the vertical hydraulic conductivity of a saturated soil. 8 The steady state in Maize was attained sooner than in banana land use corresponding to 204mm/hr and 450mm/hr respectively.This can be associated to soil disturbances during ploughing and land preparation season after season for annual crops like maize compared to banana field (Perennial) which have less soil disturbances. The scenario under maize land use may atomic number 82 to soil compaction as a result of continuous cultivation. This is emphasized by Pitt et al. , 2002 and 2008 Pitt et al. , (1999b) who found substantial reductions in infiltration rates due to soil compaction. The implication is that beyond the steady point ( color point), if more water is applied to the soil, it results into surface water runoff.Infiltration depends upon physical and hydraulic properties of the soil wet content, previous wetting history, structural changes in the layers and air entrapment. The basic infiltration rate of maize land use is lower than that of Banana land use system as seen in Appendix 1 this can be associated to a number of factors although not conclusive for the attained results 1. The initial moisture content the study was carried out in a rainy season, therefore for saturated soils, the infiltration falls to the aturated hydraulic conductivity more or less instantaneously. 2. Considering the type of land use in each of the sites Soils under Perennials (Banana Land use) are subjected to less interferences in terms of land p reparations compared to land under annuals (Maize Land use) which correlates with the obtained results of 450mm/hr and 204mm/hr respectively 3. The surrounding of the site the Maize field is on a lower elevation and near a trench which collects water, therefore its possible that the soils could easily reach saturation 9 Infiltration rate mm/hr 000 1800 1600 1 cd 1200 1000 800 600 400 200 0 1 2 3 4 5 6 7 8 9 10 11 12 13 Infiltration rate,mm/hr infiltration rate mm/hr Time(minutes) Figure 1 Infiltration Curve of Banana field Cummulative infiltration cummulative infiltration,mm 500 450 400 350 300 250 200 150 100 50 0 1 2 3 4 5 6 7 8 9 10 11 12 13 Cummulative infiltration Time,hrs Figure 2 Cumulative Infiltration of Banana Field In Banana land use, Infiltration was recorded at time intervals of 1, 5 and 10 minutes and in Maize land use it was at 3, 6 and 10 minutes time intervals (Appendix 1) 10Infiltration rate/hr 800 Infiltration rate mm/hr 700 600 500 400 300 200 100 0 1 2 3 4 5 6 7 8 Infiltration rate/hr Time,hrs Figure 3 Infiltration curve of Maize Field Cummulative infiltration Cummulative infiltration,mm 350 300 250 200 150 100 50 0 1 2 3 4 5 6 7 8 Cummulative infiltration Time,hrs Figure 4 Cumulative infiltration of Maize Field 11 Table 2 below compares the infiltration rates of two sites, classified according to the texture of the soil profiles in Banana and Maize land use systems.In each set of measurements, the infiltration rate of the Banana field belonging to the sandy clay loam was much higher than Maize field belonging to clay loam because of the variation in the physical properties of the two textural classes. In the banana field, basic infiltration rate was attained at 450mm/hr which is higher than that of maize field, 204mm/hr and this explains the relationship between soil texture, structure and infiltration which was obtained in our results where the Banana field with sandy clay loams having larger pores allowed in more water to infiltrate com pared to clay loam with relatively smaller pores.From our results, The banana field reached saturation earlier (40th minute) than the Maize field (49th minute) which deviates from the assumption that the field at lower elevation reaches saturation earlier than the other on the higher elevation, and this case the maize field was on a lower elevation. As it is not possible to vary soil texture independently of other characteristics it is not inferred that the infiltration rates are caused by texture.Table 2 Summary of the soil texture report from the test sites Sample Percentage % Sand Banana Field Maize Field 50 40 Silt 26 26 Clay 24 34 Sand clay loam Clay loam Textural Class 12 4. 0 CONCLUSION AND RECOMMENDATION Generally from the findings, the two sites registered high basic infiltration rates with banana and maize land use having 405mm/hr and 204mm/hr respectively. The two sites as well reached saturation easily because of the amount of water that was held within the soil because of the rainy season.Several factors influenced the test measuring rapidly ever-changing water levels was difficult especially for one minute time intervals and therefore subject to inaccuracy and the local site features, challenges in elevation and the soils being too soft which kept altering the position of the ruler and varying the depth thus may have affected individual test results. Therefore the study required more data collection and time to be able to sample many sites at different time intervals. For this study, tests were conducted during a rainy period in December, 2012, where the water table was expected to be above most soil layers.However, Infiltration is a key parameter in Watershed management therefore Properly designed and constructed infiltration facilities can be one of the most effective flow control (and water quality treatment) , and should be encouraged where conditions are appropriate (Ecology, 2005). Additionally infiltration separates water into two major c omponents surface runoff and submerged recharge, therefore assessment and Evaluation of runoff risk has assumed an increase importance because of concerns about associated pollution hazards in which pollutants are likely to be transferred from soil to rivers and lakes.The speed of irrigation of fields is based on infiltration tests and data in surface irrigation, infiltration changes dramatically throughout the irrigation season. The water movements alter the surface structure and geometry which in turn affect infiltration rates therefore accurate determination of infiltration rates is essential for rock-steady prediction of surface runoff. As environmental impact assessments are bear on with long-term effects, it is essential that the 13 infiltration data on which they are based should be reasonably stable. For planning purposes it is essential to know the stability of infiltration data. 4 5. 0 REFERENCES American Society for Testing and Materials, 1994, stock(a) test method for infiltration rate of soils in field using double-ring infiltrometer ASTM Publication D-3385-94, 7 p. Bouyoucos, G. J. 1962. Hydrometer method improved for making particle size analysis of soils. Agron. J. 54464-465. Ecology (2005) Stormwater counseling Manual for horse opera Washington Olympia, WA. Washington State Department of Ecology Water persona Program. Publication Numbers 05-10-029 through 05-10-033. http//www. ecy. wa. gov/pubs/0510029. pdf Gregory, J. H. , Dukes, M. D. , Miller, G. L. , and Jones P.H. (2005) Analysis of double-ring infiltration techniques and development of a simple automatic water delivery system. Applied Turfgrass Science. Haghighi. F. , & Gorjiz, M. & Shorafa M. (2010). Effects of Land Use Change on Important Soil Properties. Land Degrad. Develop. 21, 496502. Horton, R. E. , 1940, An advance towards a physical interpretation of infiltration capacity Soils Science Society of America Proceedings, v. 5, p. 399-417. Osuji, G. E,Okon M. A Chukwuma and Nw aire (2010) Infiltration characteristics of soils under selected landuse practices in Oweri, Southern Nigeria.World ledger of Agricultural Sciences 6(3) 322 326 Pitt, R. J. Lantrip R. Harrison C. Henry, and D. Hue (1999b) Infiltration through Disturbed Urban Soils and Compost-Amended Soil Effects on Runoff Quality and Quantity EPA 600-R-00-016. U. S. Environmental protective cover Agency. National Risk Management Research Laboratory. Office of Research and Development. Cincinnati, OH 231 pp. Pitt, R Chen, S. -E Clark, S. E (2002) Compacted Urban Soils Effects on Infiltration and Bioretention Stormwater Control Designs Proc. , 9th Int. Conf. on Urban Drainage (9ICUD).Portland, Oregon. Pitt, R Chen, S-E Clark, S Swenson, J. , and Ong, C. K (2008) Compactions Impacts on Urban Storm-Water Infiltration J. Irrig. and Drain. Engrg. , 134(5), 652-658. Rubin, J. , and Steinhardt, R. , 1963, Soils water relations during rain infiltration Part ITheory Soils Science Society of America Proce edings, v. 27, p. 246-251 Saxton, K. E. , W. L. Rawls, J. S. Rosenberger and R. I Papendick, 1986. Estimating generalized soil water characteristics from texture. Soil Sci. Soc. Amer. J. , 50 1031-1036 15 Schwartz, R. C. , Unger, P. W. Evett S. R. , 2000. Land use effects on soil hydraulicproperties. Suresh, D. (2008). Land and Water Management Principles New Delhi, Shansi Publishers Taylor, M. , M. Mulholland and D. Thornburrow,2009. Infiltration Characteristics of Soils Under forestry and Agriculture in the Upper Waikato Catchment. promulgate TR/18 http// www. ew. govt. nz/publications/ Technical-Reports/ TR-200918/ Zhou, X. , Lin, H. S. , White, E. A. , 2008. Surface soil hydraulic properties in four soil series under different land uses and their temporal changes. Catena. 73, 180-188. 16APPENDIX Appendix 1 Data sheet for Infiltration for Banana and Maize Fields Banana Field Time Reading clock on difference, Cumulative min time, min Infiltration Water Level, Infiltration, Infi ltratio rate cm cm n, mm mm/min Infiltration rate mm/hr Cumulative infiltration, mm 1232 1233 1234 1235 1236 1237 1242 1247 1252 1257 1302 1307 1 1 1 1 1 5 5 5 5 5 10 1 2 3 4 5 10 15 20 25 30 40 12. 0 13. 5 13. 8 14. 0 14. 3 9. 4 12. 8 11. 0 12. 0 12. 7 9. 8 15. 0 15. 0 15. 0 15. 0 15. 0 15. 0 15. 0 15. 0 17. 0 17. 3 17. 3 17. 5 3. 0 1. 5 1. 2 1. 0 0. 7 5. 6 2. 2 4. 0 5. 0 4. 6 7. 5 17 30 15 12 10 7 56 22 40 50 46 75