Rapid land use changes have been observed in recent years in central Ethiopia. )e shift from natural ecosystem to artificialecosystem is the main direction of change. )erefore, this study was initiated to assess the effects of land use types on selected soilproperties inMeja watershed, central highlands of Ethiopia.)e randomized complete block design, including three adjacent landuse types as treatments with three replications and two soil depths (0–15 and 15–30 cm), was applied in this study. )ere weresignificant differences in some soil properties among the three land use types. Lower soil pH and electric conductivity wereobserved in cultivated land soils than Eucalyptus woodlots soils. )is has indicated the worsening soil conditions due to the shiftfrom Eucalyptus woodlots to cultivated land. Less decomposition rate of the Eucalyptus leaves and debris collection for fuel couldresult in lowest soil organic carbon at the upper layer of Eucalyptus woodlot soils. However, the highest soil organic carbon at thelower layer was observed in Eucalyptus woodlot soils. )e presence of highest soil potassium, cation exchange capacity, andexchangeable potassium in cultivated land soil was related to application of artificial fertilizers. Grassland soils have highestexchangeable sodium at the lower layer while highest soil carbon and sum cations at the upper layer, which can be related to thegrass root biomass return and less surface runoff on grassland. )ere was the highest exchangeable sodium percentage onEucalyptus woodlot soils at the upper layer; it can be due to the less surface nutrient movement and growth characteristics of thetree. )e soils in cultivated land was shifted to more acidic and less electric conductivity.)is shift can lead to soil qualitydeterioration that affects the productivity of the soils in the future.Nutrient leaching, application of artificial fertilizer, soil erosion,and continuous farming have affected the soil properties in cultivated land. )e presence of highest exchangeable sodiumpercentage and lowest sum of cations at the upper layer of soil in Eucalyptus woodlot should be noted for management anddecision makers. )e previous negative speculations on Eucalyptus woodlots which can be related with the soil texture, soilmoisture, bulk density, total nitrogen, exchangeable magnesium, calcium, and available sulfur should be avoided because therewere no significant differences observed among the three land use types in the study area. )e study recommends further studieson the effects of Eucalyptus on soil properties by comparing among different ages and species of Eucalyptus. Finally, planting ofEucalyptus on central highlands of Ethiopia should be supported by land use management decision.
1. Introduction
Land use, which is human driven activities on land, is one ofthe major characteristics of land [1]. Land use type coulddetermine the total production from the land and the statusof the producer. )e land use type could be determined bythe need of producer, the environmental condition (soil,climate, rainfall, altitude, etc.), socioeconomic status (land
lord, tiller, or peasant), and political (tenure, land policy, andownership) and cultural manners (beliefs, norms, and by-laws on the land) of the given area [2, 3]. )e aforemen-tioned factors could influence the owner to decide the type ofland use on their land. Among the factors that could in-fluence the user’s preference is the soil condition of the field.)e soil condition can be identified by analyzing the soilproperties and comparing with the standards.
HindawiApplied and Environmental Soil ScienceVolume 2020, Article ID 7026929, 9 pageshttps://doi.org/10.1155/2020/7026929
Rapid population growth is believed to influence the typeof land use and the rate of expansion of specific land use type[3, 4]. )is could affect the soil properties of a given landwhen it is changed from natural to artificial land use systemor vice versa. )e intensified agricultural land expansion onthe expense of the loss natural environment could also leadto severe land degradation. In the central highlands ofEthiopia, there is significant land use change from naturalecosystem to artificial ecosystem within five decades [5–7].Recently, Eucalyptus woodlot has joined the artificial eco-system with rapidly expanding on grassland, woodland,riverside wetlands, cultivated land, and degraded land in thecentral highlands of Ethiopia [6–10].
Eucalyptus, as economic and social problem relievingtree species, is expanding in the central highlands of Ethiopia[6, 7, 9, 11]. )e species was planted in the highlands ofEthiopia in the end of 19th century as the source of fuel woodfor the settlers of the newly established capital city ofEthiopia [12]. In some places, it has expanded to 18% within30 years with farmers’ demand [9, 10, 13]. Eucalyptus hasbenefited farmers with filling household fuelwood demand,improving income, and providing social and cultural valueand environmental benefits. [14–16]. However, many stilldid not accept its planting by raising concerns on its impactssuch as water consumption, nutrient competitiveness, soilerosion, and land degradation [10, 17–19].
Various studies have been done to quantify the effect ofland use types on soil properties in Ethiopia[3, 9, 11, 20–22]. Some have compared the natural forestand woodland with the artificial land uses [3, 20]. Fur-thermore, some studies have compared the effects of dif-ferent cultivated land along ages on soil properties [20, 21].)e effects of plantation forest and natural forest on soilproperties were also studied [23]. Some have compared theeffects of conserved areas, cultivated land, plantation, andnatural forest on soil properties. Zerfu et al., [24] havecompared the effect of Eucalyptus on soil properties beforeand after harvesting. Chanie et al. [10] have studied thevariation of soil properties along different distances fromEucalyptus tree. Some have compared the effect of Euca-lyptus along ages [25].
However, the effects of land use types, comparing theeffects of natural land use (grassland) and the artificial landuse (cultivated land and Eucalyptus woodlots) on soil, wereless studied in the central highlands of Ethiopia and else-where. )us, the farmers’ Eucalyptus planting trend is in-creasing with the expansion of natural and cultivated land.Currently, due to its social and economic benefits, it is difficultto hinder farmers to not plant Eucalyptus on their land[13, 26–28]. However, it is beneficial to understand the effectsof the land use types on soil properties to support generatingland use management options. )erefore, the objective of thisstudy was to assess the effects of land use types on selected soilproperties in the central highlands of Ethiopia.
2. Methods
2.1. Description of the Study Area. )e study was conductedat Meja watershed in West Shewa zone, Central Ethiopia. It
is found 110 km west of the capital, Addis Ababa (Figure 1).)e watershed is found in two districts: Jeldu and Dendi.)ewatershed is located within 9°07′ to 9°17′N and 38°02′ to38°07′E, with an altitude ranging from 2400 to 3200m abovemean sea level. )e watershed is also found in southernupper Blue Nile basin. )e total area of the watershed is10107 ha.
)e mean annual temperature ranges from 17°C to 25°C.)e rainfall is bimodal with the short rainy season fromFebruary to May and long rainy season from June to Sep-tember.)emean annual rainfall is 1400mm though there isvariation of rainfall amount along the altitude. )e agro-ecology of the site is grouped locally under Dega andWurch(cool highlands with sufficient rainfall, with some extremecool weather condition). Eucalyptus globulus is the mainexotic tree planted in the watershed. Very few places arecovered by small patches of natural forest; otherwise,bushlands are dominated the riversides, ridges, and steepslope. Scattered trees are still visible on cultivated land andgrassland. Acacia abyssinica, Hagenia abyssinica, and Bud-dleja polystachya are some of the indigenous trees andshrubs in the area. Eucalyptus globulus woodlots areabundant in the watershed replacing bush land, cultivatedland, and marginal grazing lands.
)e major river in the watershed is the Meja River, whichis one of the tributaries of the Nile River. )e Meja Riveroriginates at high altitude just near Galessa village in theDendi district. )e head waters are in a flat wide valley, whichis a wetland heavily utilized for livestock grazing in Galessa.Many tributaries drain into the Meja river from both the eastand west sides of the watershed. )e river flows throughoutthe year with high flow at July, August, and September. )esouthern upper Blue Nile, which includes the study area, isdominated by Vertisol. )e soil in the study area is classifiedunder Pellic Vertisol. )e textural class of the soil at uppersection of the watershed is dominated by clay loam and claysoil. )e lower section of the watershed has loam soil. )e soiltextural class of this study area is clay soil. )e soil pH valueranges from 4.9 to 5.9, which is moderately acidic soil. Soilerosion by water is common threat for sustainability ofcultivated land in the study area.
)e land use of the area is predominantly mixed crop-livestock-tree production system. Major crops grown in thearea are barley (Hordeum vulgare), wheat (Triticum vulgare),potato (Solanum tuberosum), andmaize (Zeamays). Livestockproduction (cattle, sheep, and horses) for various purposes isalso practiced. Eucalyptus plantations and woodlots areproduced mainly for sale in the study area. )e major cashsources for farmers in the watershed are from sale of potatoand Eucalyptus.)e estimated population of the study area is42000. )e estimated annual population growth is 2.5%.)eaverage number of people per household is 6 people. Land-holding size per household ranges from 0 to 4 hectares. Half ofthe population are youth in the study area.. Majority of thepopulation live in the rural area.
2.2. Experimental Design. )e comparison of the effectsdifferent land use types on selected soil properties was
2 Applied and Environmental Soil Science
studied by collecting soil samples from three different landuse types. )e experimental design for this study was ran-domized complete block design (RCBD) in which the landuse types were considered as treatments. )ree land usetypes, namely, Eucalyptus woodlot, cultivated land, andgrassland, were selected for comparison as treatments.Grassland was considered as control treatment in thestudy.)e three adjacent land use types, which shares similarbiophysical condition such as soil and slope, are grouped in ablock. . Four replications of each land use type were used inthe four different sites forming a total of twelve sample plots.
2.3. Soil Sampling. )e soil samples were collected only onetime from three land use types at four different sites in Mejawatershed, Jeldu district. From each site, three soil samplinglocations were systematically selected with having three ad-jacent land use types.)e three land use types within each sitehave similar topography and other conditions, which madethe local soil forming factors relatively uniform (Table 1). )esoil samples were collected at twelve points with four repli-cations of land use types in the study area. Plot with squaredimension (20m× 20m) was laid at the middle of each landuse types. )e pits were dug at four corners and center of theplots using auger, and two soil samples were taken from thepit at two soil depths (0–15 cm and 15–30 cm).
2.4. Soil LaboratoryAnalysis. )e collected soil samples werebulked to one composite sample with similar depth at eachplot of the land use types. Two composite soil samples werecollected from each land use types. In total, six compositesamples were collected from each site and twenty-fourcomposite samples were collected from the study site. )ecomposited sample that weighs one kilogram was taken,
properly labelled, and packed with plastic bags prior totransporting it to laboratory.
For bulk density and moisture analysis, two soil samplesat depths 0–10 cm and 20–30 cm were taken using coresampler (height� 10 cm and diameter� 7.2 cm) and theirweight was also measured directly at the field. )e soilsamples were collected in a labelled polyethylene bag, reg-istered, and transported to soil laboratory of water worksdesign and supervision enterprise at Addis Ababa, Ethiopia.All soil samples were air-dried at room temperature andsieved (mesh size 2mm).
Soil organic carbon (OC) was determined using theWalkley and Black method as stated in Nelson and Sommers[29]. Total nitrogen (TN) was estimated by the Kjeldhalmethod as used by Bremner [30]. )e soil texture was de-termined using the hydrometer method [31]. Soil pH wasdetermined by a pH meter. Electrical conductivity of the soilwas determined on the saturated paste. Bulk density wasdetermined by dividing the oven dry mass (105°C) by thevolume of the core. Exchangeable cations (Ca2+, K+, Mg2+,and Na+) were determined using 1M ammonium acetate atpH of 7.0 [32]. Cation exchange capacity (CEC) was calcu-lated by summing up the charge concentrations of Ca2+, K+,Mg2+, and Na+. Available potassium (K) was determined byflame photometer with dissolved 0.3728 g of dried KCl in onelitre of extracting solution [33]. Exchangeable sodium per-centage (ESP) was computed by dividing exchangeable so-dium by soil CEC and multiplying by 100. Available sulfur ofthe soil was extracted by the Mehlich-3 multinutrient ex-traction method [34]. Available phosphorus was determinedby the Bray 2 method [35].
2.5. Statistical Analysis. )e soil laboratory results wereanalyzed with Statistical Package for Social Sciences (SPSS)
0 410 820 1,640kilometers
0 245 490 980 kilometers
0 5 10 20 kilometers
Oromia region
Jeldu_woredaOromia region
Jeldu Woreda
Study siteJeldu_woredaSampling points
1 : 500,000
N
N
N
Figure 1: Map of the study area.
Applied and Environmental Soil Science 3
software version 20 [36]. )e data were tested for normalityprior to analysis. Analysis of variance (ANOVA) test was runusing the multivariate general linear model to test the effectsof land use type on dependent variables. Significant meanswere separated using least significant difference (LSD) at 5%significance level for pair wise comparison of means to assessthe mean differences of the land uses and depth levelsdepending on soil chemical properties.
3. Results
3.1. Soil pH, EC, Texture,Moisture, andBulkDensity. )e pH(H2O) of the soils in the three land use types is groupedunder strongly acidic (5.1–5.5) class. )ere was a significantdifference (p≤ 0.05) in soil pH among land use types in bothlayers (Table 2). )e pH of soils in grassland>Eucalyptuswoodlot> cultivated land in upper layer and the pH ofgrassland> cultivated land>Eucalyptus woodlot in thelower layer. )e soil EC of the study site ranges from0.75–0.92mS/cm; this could indicate that it is grouped intothe soil salinity class of nonsaline soil. )e EC of the soilscould depend on the amount of moisture present in the soil.)ere was a significant difference (p≤ 0.05) in soil ECamong land use types in the upper layer (Table 2). )egrassland soils had the highest EC value in the upper layer,while cultivated land soils had the lowest EC value in theupper layer as compared to others.
)ere was no significant difference (p≤ 0.05) in soilmoisture, texture, and bulk density among land use types inboth layers (Table 2). )e soils of the study area are groupedunder clay class according to USDA classification.)ere washighest soil moisture content in grassland at the upper layer,while the highest soil moisture content was observed ineucalyptus woodlot soil in the lower layer. Cultivated landhad the highest bulk density value in both layers, whilegrassland had the lowest bulk density in both layers ascompared to others.
3.2. Soil Organic Carbon, Total Nitrogen, Potassium, andAvailable S and P. )e results of soil organic C, total N,potassium, and available S and P are listed in Table 3. )erewas a significant difference (p≤ 0.05) in soil organic carboncontent among land use types in the upper layer (Table 3).
)e soil organic carbon content of grassland> cultivatedland> Eucalyptus woodlot in the upper layer. )e uppersurface of the soils in grassland contains higher soil organiccarbon than in the lower surface. )ere was higher soilorganic carbon deposition in the Eucalyptus woodlot soils atthe lower layer. However, there was less soil organic carbonon Eucalyptus woodlots in the upper surface as compared tothe other two land use types.
Soil potassium is classified as macronutrient that is anessential nutrient for plant growth. )ere was a significantdifference (p≤ 0.05) in soil potassium content among land usetypes in the lower layer (Table 3). Cultivated land soils hadhighest potassium content in the lower layer, while grasslandsoils had lowest potassium content in the lower layer. However,there was no significant difference in soil potassium contentamong land use types in the upper layer. )e soil CEC of thestudy site (21.1–31.6 meq/100 g) is rated as high based on itsvalue [37]. )ere was a significant difference (p≤ 0.05) in soilCEC among Eucalyptuswoodlot, cultivated land, and grasslandin the upper layer (Table 3). )e CEC of cultivatedland> grassland>Eucalyptuswoodlot in the upper layer.)erewas no significant difference (p≤ 0.05) in total nitrogen,available S, and available P among land use types in both layers(Table 3). Grassland had highest total nitrogen content in bothlayers, while Eucalyptus woodlot soils had total nitrogencontent in both layers. Cultivated land and eucalyptus had thehighest and lowest available S, respectively, in both layers.Eucalyptus woodlots had highest available P, while grasslandhad the lowest available P in both layers.
3.3. Soil Exchangeable Cations (Na, K, Ca, and MG), Sum ofCations, and ESP. )ere was a significant difference(p≤ 0.05) in soil exchangeable sodium among land use typesin the lower layer. )e exchangeable Na+ soils of grass-land> Eucalyptus woodlot> cultivated land in the lowerlayer (Table 4). )e exchangeable potassium level of thesoils in the study area could be grouped under low category(0.2–0.4 cmol (+)/kg of K+). )ere was a significant dif-ference (p≤ 0.05) in soil exchangeable potassium amongland use types in the lower layer (Table 4). Cultivated landsoils had the highest soil exchangeable potassium, whilegrassland soils had lowest soil exchangeable potassium in theupper layer. )e sum of cations is directly related with CEC
Table 1: Mean of biophysical conditions of the sampling plots.
Land usetypes
Moisturecontent (%)
Soiltemp.(°C)
Slopedegree(°)
Stonecover(cm)
Ground cover (count)Crowncover % Plant type Planting
2 meters apart, 4years old, 8 meterheight, and 10 cm
DBH
4 Applied and Environmental Soil Science
because it is one part of measurement to determine CEC. As itis listed above in Table 3, the CEC of the three land use typeswas significantly different among each other. )e sum ofcations value could be varied due to the presence of othercations and soil physical condition. )us, there was a sig-nificant difference (p≤ 0.05) in sum of cations of the soilsamong land use types in the upper layer. Grassland soils hadhighest sum of cations, while eucalyptus woodlot soils hadlowest sum of cations in the upper layer (Table 4).
)e soil exchangeable sodium percentage (ESP) of thestudy site ranges from 8.3% to 9.5%. If the ESP of the soil isless than 15%, the soil will not be sodic. In this case, thesoil of the study site was not sodic. )ere was a significantdifference (p≤ 0.05) in soil ESP among land use types in theupper layer (Table 4). Eucalyptus woodlot soils had highestESP, while grassland soils had the lowest ESP in the upperlayer.
)ere was no significant difference (p≤ 0.05) in soilexchangeable cations calcium and magnesium among landuse types in both layers (Table 4). Grassland soils had highestexchangeable calcium, while Eucalyptus woodlot soils hadlowest exchangeable calcium in both layers. Grassland soilshad highest exchangeable magnesium, while cultivated landsoils had lowest exchangeable magnesium in both layers ascompared to the others.
4. Discussion
4.1. Effects of Land Use Types on pH, EC, Texture, Moisture,and Bulk Density. )e soils in cultivated land were moreacidic than the other land use types in the upper layer. )iscan be due to application of ammonium-based fertilizers,erosion, and improper ploughing direction [38]. Differently,the pH of Eucalyptus woodlot soils was lower than that ofcultivated land and grassland soils in Ethiopia [3, 11, 39, 40].)e soil pH can influence the solubility and availability ofnutrients in the soil. )e soil pH can vary within shortdistance due to nitrification, root activity, and decompositionof organic matter. According to Chemeda et al. [41], the pH ofgrassland soils was higher than that of the soils in cultivatedland and forest land. But, Yimer et al. [42] have found that thepH of cultivated land soils was higher than that of the soils ingrassland and forest land. )e reason for lower soil pH in theEucalyptus woodlot can be due to frequent cation uptake andremoval of cations around the tree [11].
)e soil EC value was related with the soil pH in the upperlayer. )e EC level can affect the soil texture, CEC, organicmatter condition, and subsoil characteristics of the soils.Various studies have found higher EC in grassland soils ascompared to the soils in cultivated land and other land usetypes [43–45]. )e lower EC value in cultivated land soils can
Table 3: Mean (±SEM) of selected soil chemical properties across land uses and soil depths.
Land uses Depth (cm) OC (%) TN (%) K (meq/100 g) Available S (%) Available P (mg/kg) CEC (meq/100 g)
)e superscripts across a column in different letters represent that they are significantly different at p ≤ 0.05.
Applied and Environmental Soil Science 5
be related with the loss of exchangeable base from the soil dueto leaching and erosion as a result of continuous farming.
4.2. Effects of Land Use Types on Selected Important SoilNutrients. In several findings, grassland soils can accu-mulate higher soil carbon than other land use typesexcept natural forest [3, 45–47].)e decomposed humusfrom grassroots and above-ground biomass in the upperlayer of grassland soils could increase the carbon content.)e upper surface of the grassland soils contains highersoil carbon than the lower surface. It is due to thepresence of easily decomposing materials on the uppersurface than other land use types.
In the other case, the reason behind higher soil organiccarbon content in the cultivated land than Eucalyptuswoodlotswas due to fertilizer application and higher leaf decompositionof the cultivated crops. However, there was higher soil organiccarbon in Eucalyptus woodlot than the other two land uses inthe lower layer. )is could be due to slow decomposing rate ofEucalyptus leaves and debris collection for fuel wood that couldreduce the accumulation of organic matter under the treecanopy. Similar to this study, grassland soils had higher soilorganic carbon than cultivated land in other studies[41, 42, 45, 47]. )is is due to the presence of numerousamounts of grass root growth and biomass turnover rate; inaddition to this, less erosion and absence of tillage couldlead to higher accumulation of soil organic carbon in thegrassland soils. On contrary to the above, studies havefound higher soil organic carbon in Eucalyptus woodlotsoils than grassland and cultivated land soils in the upperlayer [3, 21, 40, 48]. In general, the soil organic carboncontent for the study site soils ranges from 2.47%–3.78%,which could be grouped under optimum status.
)e occurrence of higher potassium in the lower layer ofcultivated land soils can be related with the application offertilizers and the leaching of nutrient to the lower layer due toploughing [21]. Similar findings have observed significantlyhigher potassium content in the cultivated land soils ascompared to other land use types [45]. )e soil potassiumcontent of the study site rages from 0.16 to 41meq/100g, whichcould be considered as very low for plant growth on the soil.
)e higher CEC in the upper layer of cultivated land soilscan be related with the presence of higher exchangeablesodium and potassium in the soils that can be related to theapplication of fertilizer. Similarly, other findings have ob-served higher CEC in the cultivated land soils as compared toother land use types [3]. However, Chemeda et al. [41] andAdugna and Abegaz [22] have found higher CEC in grasslandsoils than cultivated land soils. CEC can be related with soilcarbon, clay content, and pH value of the soil. )e lower CECvalue in Eucalyptuswoodlot soils can be related with the lowersoils’ pH value (more acidic soil). )e other reason can bedepletion of exchangeable bases in Eucalyptus and grasslandsoils. Application of fertilizers, which can initiate the presenceof cations on cultivated land, can also affect the CEC ofcultivated land soils. )e value of CEC in upper layer ofcultivated land is smaller than that in the lower layer; thiscould be resulted due to exchangeable sodium leaching.
4.3. Effects of Land Use Types on Exchangeable Cations andESP. )e result has also indicated the inverse relation of soilexchangeable sodium with soil potassium in the similarlayer. )is can be also related with the application of fer-tilizers and nutrient movement to the lower layer. In ad-dition, it can be connected to the crop nutrient uptake fortheir growth.)is result matches with the finding of Seyoum[44] and Feyisa et al. [45] by the higher content of soilexchangeable sodium in grassland soils as compared to theother land use types. Other studies have observed higher soilexchangeable sodium in the lower layer of the cultivated landsoils as compared to the upper layer [43, 44]. )is is due toleaching of exchangeable cations, in this case, sodium.Similarly, on grassland soils, the nutrient loss can be reduceddue to lesser surface water movement. So, it was observed thehigher soil exchangeable sodium in grassland soils ascompared to cultivated land. However, other studies havefound higher soil exchangeable sodium in cultivated landsoils than grassland soils in both layers [21, 43].
)e aforementioned result about the soil exchangeablepotassium content has shown the direct relationship of thepresence of soil potassium and exchangeable potassium undersimilar land use type soils. )e presence of higher ex-changeable potassium in cultivated land soils can be related tothe type of fertilizers applied on the cultivated land soils.Oppositely, Lemma and Olsen [49] have found significantvariation between cultivated land and Eucalyptus woodlotsoils. )e result has indicated that there was higher soil ex-changeable potassium in the Eucalyptus woodlot soils thancultivated land soils [3]. However, other studies have alsofound higher soil exchangeable potassium in the cultivatedland soils as compared to other land use types [20–22].
)e sum of cations in grassland soils was higher ascompared to the other land use types. )is is due to lesssurface water movement in grassland and lesser con-sumption of these cations by grasses. Other findings havealso observed higher sum of cations in the grassland soils ascompared to the other land use types [45]. In the other case,the lower sum of cations in the Eucalyptus woodlot soils atupper layer was observed which is due to the root charac-teristics of the tree. )e Eucalyptus tree’s deep roots can alsoinfluence the downwardmovement of these cations from theupper layer so that lower value of cations was observed in theupper layer of Eucalyptus woodlot soils.
)e presence and absence of sodium in the soil can berelated to the plant growth characteristics and the nutrientmovement in the soil at surface layer. Here, it can be relatedto surface water movement and fertilizers application. Astudy has indicated that there was higher ESP in the cul-tivated land soil than grassland and other land use types [50].
5. Conclusions
Land use types can affect the soil properties and the presenceof essential nutrients in the soils. Central Ethiopia has ob-served significant change in land use as a result of expansionof cultivated land and Eucalyptuswoodlots. )e result of thisstudy has shown that there was a significant difference in soilproperties due to the effects of land use types in the study
6 Applied and Environmental Soil Science
area. )e soil pH and EC have shown significant differenceamong the three land uses types in the upper layer. Cul-tivated land soils have shown lower pH and EC than Eu-calyptus woodlot soils in the upper layer. )is is due to theapplication of ammonium base fertilizers, cation loss as aresult of leaching, and water erosion due to continuousfarming. )ere was a significant difference in soil organiccarbon among land use types with lowest in Eucalyptuswoodlots soils in upper layer. )e highest soil organiccarbon was observed in lower layer of the Eucalyptuswoodlot soils. )is could be due to less decomposing rate ofEucalyptus leaves and the collection of debris for fuel wood,which could reduce the accumulation of organic matter inEucalyptus woodlots. Grassland soils have highest soilorganic carbon in the upper layer as a result of highernumber of grass root growth and biomass turnover rate.Furthermore, there was a significant difference in soilpotassium, CEC, exchangeable sodium, exchangeable po-tassium, sum of cations, and ESP among land use types.)ere was the highest potassium value in cultivated landsoils as compared to others due to leaching of appliedfertilizers during soil sampling. Related with this, therewere highest CEC and exchangeable potassium in the upperlayer of cultivated land soils.)is can be related with ap-plication of fertilizer. However, exchangeable sodium washighest in grassland soils at lower layer. )is can be relatedwith leaching of nutrients from the upper layer.)e highestsum of cations was seen in grassland soils at the upper layer.)is can be related with less nutrient loss due to less surfacerunoff from the field.
)e highest ESP was observed in Eucalyptus woodlotsoil at the upper layer. )is is due to the less surface nu-trient movement and growth characteristics of the tree. Ingeneral, the study has observed important soil propertieswhich were significantly affected due to the effects of landuse types. Cultivated land soils were shifted to more acidicand lesser EC content soil, which could lead to less pro-ductive soil in the future. Nutrient leaching, application offertilizers, soil erosion, and continuous farming have af-fected the soil properties in cultivated land. )ese effectsshould be managed with proper and sustainable farmmanagement practices in order to avoid the degradation ofcultivated land soils from the study area. )e presence ofthe highest ESP and lowest sum of cations at the upper layerand lowest pH at the lower layer in Eucalyptuswoodlot soilsshould be noted for management and decision makers.)ere were no significant differences in soil texture, soilmoisture, bulk density, total nitrogen, exchangeablemagnesium, exchangeable calcium, available sulfur, andavailable phosphorus among the three land use types. )iscould avoid the negative rumors on Eucalyptus woodlots,which can be related with the aforementioned soil prop-erties in the study area.
)e study also recommended further studies on theeffects of Eucalyptus on soil properties by comparingamong different ages and species of Eucalyptus. Finally,planting of Eucalyptus on central highlands of Ethiopiashould be supported by proper land use managementdecision.
Abbreviations
ANOVA: Analysis of varianceCEC: Cation exchange capacityEC: Electrical conductivityESP: Exchangeable sodium percentagepH: Potential of hydrogenLSD: Least significant differenceRCBD: Randomized complete block designSPSS: Statistical Package for Social SciencesUSDA: United States Department of Agriculture.
Data Availability
)e data used to support the findings of this study areavailable from the corresponding author upon request.
Conflicts of Interest
)e author declares that there are no conflicts of interest.
Acknowledgments
)is study was funded by the International Foundation forScience (IFS) grant (no. L3-D-5826-1; 2015), and the authorrecognizes the support given by the organization.)e authoralso appreciates the support given by the Central EthiopiaEnvironment and Forestry Research Center in Ethiopia.
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