Ethiopian Journal of Science and Sustainable Development

e-ISSN 2663-3205 Volume 10 (1), 2023

Journal Home Page: www.ejssd.astu.edu.et ASTU

Research Paper

Assessment of Soil Acidity and Determination of Lime Requirement under Different

Land Uses in Gumer District, Southern Ethiopia

Aliyu Nesru1, Achalu Chimdi2, Wondwosen Tena3

1Department of Natural Resources Management, Wolkite University, Wolkite, Ethiopia

2Department of Natural Resource Management, Ambo University, Ambo, Ethiopia
3Department of Plant Biology and Biodiversity Management, Addis Ababa University, Addis Ababa, Ethiopia

Article Info Abstract

Article History:

Received 02 June 2022

Received in revised form

18 November 2022

Accepted 28 December

2022

The study was initiated to assess the level of soil acidity and lime requirement of four types of

land uses (forest lands, grazing lands, cultivated lands, and Eucalyptus tree plantation) and in

replications from 0-20 cm soil depth. Lime requirement was evaluated by exchangeable acidity

and buffer solution methods. The data were analyzed by SAS software, version 9.1. The study

revealed that soils of cultivated and Eucalyptus lands were very strongly acidic with mean of

pH 4.8 and 5.0, whereas soils of grazing lands were strongly acidic with pH 5.5 and forest lands

were moderately acidic with pH 5.7and 5.6 in both kebeles, respectively. Meaningfully higher

pH, OM, TN, CEC, exchangeable Ca2+, and Mg2+ were noted under forest lands as compared

to the remaining land uses. However, meaningfully lower exchangeable acidity (EA) (1.06)

and percentage acid saturation (PAS) (5.18) were obtained in the forest lands than in the other

land uses. Significantly higher available P (2.54) was noted in the grazing land, followed by

natural forest (1.77) land for Berchernamocheya kebele, and higher available P was recorded

under forest (2.50), followed by grazing land (2.37) for Badnayegor kebele. Significantly

higher exchangeable K+ (1.29) and Na+ (0.63) were observed in grazing land for Badnayegor

and Berchernamocheya Kebeles, respectively. The results of the lime requirement revealed that

using the SMP buffer solution method recorded 4.1-11.3 t/ha while using the exchangeable

acidity method recorded 1.3-6.7 t/ha across the land uses for both kebeles. Based on lime

requirement determination methods, the amount of lime required highly varies among the land

uses. The investigation showed that soil acidification is a serious problem in the study areas.

Thus, integrated land management needs to be practiced to overcome the problem of soil

acidification and achieve sustainable agricultural production.

Keywords:

Land Uses,

Lime Requirement,

Soil Acidity,

Soil Properties,

1. Introduction

Different land uses have various influences on soil

deprivation on physicochemical properties (Alelgn et

al., 2021). Assessment of soil quality indicators related

to updated soil nutrient management practices is a

suitable and primary indicator for sustainable

agricultural land management (Agbede, 2010; Wang et

al., 2010). Such an assessment is used to understand

Corresponding author, e-mail: achaluchimdi@yahoo.com

https://doi.org/10.20372/ejssdastu:v10.i1.2023.512

nutrient availability in soils. This knowledge can

determine whether definite land uses are suitable for a

given crop production system or not (Wang et al., 2010).

Soil acidification is one of the fundamental chemical

soil degradation problems limiting crop production and

productivity in various parts of Ethiopian highlands

receiving high rainfall. The problem is also intensifying

http://www.ejssd.astu.edu/

Aliyu Nesru et al Ethiop.J.Sci.Sustain.Dev., Vol. 10 (1), 2023

in scope in most other Ethiopian highlands, severely

limiting crop production. For instance, in most barley,

wheat, and faba bean growing areas of central and

southern Ethiopian highlands, agriculturalists have

shifted to the production of acid-tolerant crops such as

oats rather than acid-sensitive crops (Wassie & Boke,

2009; Chimdi et al., 2012). Challenges of soil

acidification are mainly related to acid soil forming

exchangeable aluminum (Al3+) and exchangeable

Hydrogen (H+) and low availability of exchangeable

basic cations. In acidic soil areas, exchangeable bases

are easily removed through leaching and crop harvest

(Lenka et al., 2007; Ermias et al., 2016).

Most of the Ethiopian agricultural lands are affected

by soil acidity and need appropriate amendment options

including the application of liming material (Birhanu et

al., 2014; Behera & Shukla, 2015; Bikila, 2019; Mesfin

et al., 2020). Therefore, soil acidity is a serious concern

calling for urgent consideration in most Ethiopian

highlands because of its impact on crop yields and soil

fertility (Chimdi et al., 2012; Chimdi, 2014; Kidanu &

Chimdi, 2018). Even though soil acidity is recognized

as an issue requiring urgent thoughtfulness in most

Ethiopian highlands, there is very limited information

about the impact of land uses on the level of acidity and

the magnitude of lime required to neutralize soil acidity

and other acidity-associated soil physicochemical

properties in Gumer district. Hence, the current research

was initiated with the specific objective of assessing the

degree of soil acidification and the level of lime needed

to reclaim acidification under three land uses.

2. Materials and Methods

2.1.Description of the study area

The current investigation was undertaken in the

Gumer District of Gurage Zone, Southern Nations-

Nationalities, and People's Regional State. The district

is located 220 kilometers south of Addis Ababa on the

main road to Jimma, and 65 kilometers from Wolkite,

the capital of Gurage Zone (Figure 1). It is found at

7º8′4″- 8o00′6″ latitude North and 37º8′9″- 38º2′00″

longitudes East.

2.1.1. Topography and climate.

Topographically, the study district is composed of a

flat plain (7%), and average slope (35%), and the

extremely sloppy area covers 58% of the district. The

altitude of the study site ranges from 2,600 to 3,170 masl

and falls in the highland agro-climatic zone. According

to Ethiopian Meteorological Agency, the average

annual rainfall of the area is 1001- 1400 mm, with a

bimodal rainfall pattern. The main rainy season ranges

from June to September and the short rain period covers

the months from February to April. The genuine rainy

season ranges from June to the end of September. The

mean maximum and minimum annual temperature of

the study area varies between 17.5oC and 10.1oC,

respectively (National meteorological agency, 2017).

2.1.2. Farming system and soil types

Agriculture is the main source of revenue in the

Gumer District. The district comprises a largely

diversified farming system that includes field crop

production (which includes Enset, Eucalyptus tree,

barley, bean, pea, and wheat as the main economic

activities and livestock rearing (cattle, goat and sheep)

as the second most important economic activity in the

district. The major vegetables grown in the area are

potato, cabbage, garlic, onion, endive, beetroot, carrot,

and many more. The data obtained from FAO (1991)

shows the soil type in the district is mainly Cambisols

and Plinthosols.

2.1.3. Site selection and soil sampling technique

Purposive field surveillance and reconnaissance

survey and selection techniques were undertaken before

selecting the study site. Among the sixteen districts of

Gurage Zone, Gumer District was purposively selected;

this was because of susceptibility to land degradation

and soil acidity in most of the highland areas of the

district. The presence of representative land uses and

topographical situation were the criteria used to identify

the study site. Accordingly, cultivated land, eucalyptus

plantation land, natural forest land, and grazing land

were selected from Brchernamocheya and Badnayegor

kebeles and considered for the study. A soil sample was

collected from each land use with a random and uniform

collection of representative soils. Replication of nearly

1 kg representative soil from the top surface (0-20 cm)

of every land use was collected, dried, sieved, prepared,

labeled, and transported for laboratory analysis. By

doing so, 24 composite soil samples were collected from

the selected land uses of the two Kebeles.

Aliyu Nesru et al Ethiop.J.Sci.Sustain.Dev., Vol. 10 (1), 2023

Figure 1: Location map of the study area

Additionally, for the determination of soil bulk

density, undisturbed 24 soil samples were taken from

each land use in replication using a core sampler.

Conversely, soil samples were grounded to pass a 0.5-

mm size sieve for analysis of total N and OC. A

randomized complete block design was conducted with

three replications.

2.2. Soil Laboratory Analysis

The analysis of soil samples was carried out at

Wolkite Soil Laboratory Center using regular

laboratory procedures and methods for the

determination of lime requirement.

2.2.1. Evaluation of selected soil parameters

Soil texture was measured through the Bouyoucos

hydrometer method, which can be written (Day (1965).

Soil bulk density was determined using the core

sampler method. An average value of soil particle

density of 2.65g cm-3 was considered for the

calculation of total soil porosity. Total porosity was

estimated from bulk and particle densities as described

by Brady and Weil (2016).

Soil pH was measured using a digital pH meter as a

suspension of a 1:2.5 soil-water ratio (Van Reeuwijk,

2002). Cation exchange capacity (CEC) and

exchangeable bases were extracted by 1M of

NH4COCH3 at (pH 7) as described by Chapman

(1965). The extracts of exchangeable Ca2+ and Mg2+ as

well as Na+ and K+ were measured using atomic

absorption spectrophotometer flame photometer,

respectively (Chapman, 1965). The CEC was

determined from the displaced NH4
+ through

distillation followed by titration. Exchangeable acid

was determined by saturating the soil with 1N KCl

solution and titrating it with NaOH as described by

McLean (1965). A neutral 1N KCl solution was used

to leach exchangeable H+ and Al3+ ions from the soil.

After the determination of Organic carbon, using wet

digestion, soil organic matter was calculated from

organic carbon (OM=1.724 * %OC)as described by

Walkley & Black (1934). Soil Total N was measured

using the Kjeldahl digestion procedure as designated

by Jackson (1958). The available P was determined by

using the Olsen method (Olsen et al., 1954). Soil

percent base saturation (PBS) was calculated by taking

the ratio of the sum of basic exchangeable cations

(Ca2+, Mg2+, Na+, and K+) ions to CEC as a percentage.

Effective CEC, PBS, and PAS were calculated as

follows:

(1)

100*
)(.

CEC

ionsNaKMgCabaseEx
PBS




Aliyu Nesru et al Ethiop.J.Sci.Sustain.Dev., Vol. 10 (1), 2023

𝐸𝐶𝐸𝐶 = (𝐸𝑥. 𝑏𝑎𝑠𝑒𝑠(𝐶𝑎2+ + 𝑀𝑔2+ + 𝐾+ + 𝑁𝑎+)

+ 𝐸𝑥. 𝐴 (2)

100*
.

ECEC

acidityEx
PAS  (3)

𝐸𝑥. 𝐴 = (EX. H+ + Ex. Al3+) (4)

2.2.2. Methods used for lime requirement (LR)

determination

The methods that were used for the lime

requirement determination for this research were

exchangeable acidity with the unbuffered neutral salt

solution method and the SMP buffer solutions

method. Shoemaker, McLean, and Pratt buffer for the

lime requirement was employed using the buffer

solutions method as developed by Shoemaker,

McLean, and Pratt (SMP) buffer solution (Shoemaker

et al., 1961). The SMP buffer method measures the

change in pH of a buffer triggered by soil acidity and

alteration in buffer pH is a quantity of lime

requirement of soil. After determination of the

prepared buffer pH, soil samples were determined by

using SMP buffer solutions, at Wolkite Soil Testing

Center, and the lime requirement was assessed by

referring to a published table, linking buffer pH to

aimed pH.

2.2.3. Extraction of exchange acidity method

Exchange acid is the total exchangeable H+ and

Al3+ adsorbed on a soil exchange complex. The

exchangeable acidity above pH 5.5 is very low or

even absent since exchangeable acidity is present

appreciably only at pH < 5.5. The soil exchangeable

acidity was determined as designated by Shoemaker

et al. (1961). The mathematical model developed by

Kamprath (1984) was used to calculate LR

determination.

𝐿𝑅, 𝐶𝑎𝐶𝑂3 (
𝑘𝑔

ℎ𝑎
)

𝑐𝑚𝑜𝑙𝐸𝐴
𝐾𝑔𝑠𝑜𝑖𝑙

∗ 0.2𝑚 ∗ 1000𝑚2 ∗ 𝐵𝐷 (
𝑚𝑔
𝑚3

) ∗ 100

200
(5)

Where: EA = Exchangeable acidity and BD = Bulk

density

2.2.4. Data Analysis:

Data generated from laboratory analysis were subjected

to analysis of variance (ANOVA) using Statistical

Analysis System (1999) version 9.1.

3. Results and Discussion

3.1.Soil Physical Properties

The analytical result showed that all soil textures

changed highly significantly (p < 0.01) in Badnayegor

and Berchernamocheya kebeles except the silt portion in

Badnayegor kebele, which significantly (p < 0.05)

varied between land uses (Table 1). In all land uses of

Berchernamocheya kebele, a sand portion was high

(52.33- 32.33%) tailed by a silt portion (39.33 - 24.67%)

and a clay portion (28.83- 16.67%). However, in

Badnayegor kebele, sand, silt, and clay fractions ranged

from 55.67 - 41.0%, 36.33 to 26.0%, and 30.0% -

15.33% respectively, in all land uses (Table 1).

Relatively, the sand fraction was the largest proportion

in all land uses of the two kebeles.

The current finding is corroborated by the findings

of Abbasi et al., (2007) and Tessema (2008). The

authors state that the disparity of soil texture between

land uses implies the effects of land uses on soil

properties triggered by different utilization and

management system of land uses (Abbasi et al., 2007;

Tessema, 2008). In Berchernamocheya kebele, soil

textural class of cultivation land (CL), EL, GL, and NF

were loam, clay loam, sandy clay loam, and sandy loam,

whereas in Badnayegor kebele, textural class of

cultivation land (CL), EL, GL) and NF was sandy clay

loam, clay loam, sandy loam and loam (Table 1).

Changes in textural class among land uses resulted from

amendment in management practices and pedogenic

practices at the study area.

3.2.Soil bulk density and total porosity

The analysis of variance depicted that land uses

significantly (P < 0.01) affected bulk density (BD) in

both kebeles. Numerically, the highest BD was found

under the grazing lands (1.41 g/cm3 and 1.44 g/cm3)

followed by cultivated lands (1.38 g/cm3 and 1.34

g/cm3). However, the lowest value of BD (1.21g/ cm3

and 1.17 g/cm3) was detected under NF followed by the

soil under EL (1.28 g/cm3 and 1.18g/cm3) for

Berchernamocheya and Badnayegor kebeles,

respectively.

Aliyu Nesru et al Ethiop.J.Sci.Sustain.Dev., Vol. 10 (1), 2023

Table1. Mean values of selected soil physical properties

Land uses Berchernamocheya kebele Badnayegor kebele

Percentage (%) Percentage(%)

Sand Clay Silt Tx. C Sand Clay Silt Tx. C

CL 44.33a 21.0b 34.67ab L 46.33b 28.33a 25.33b SL

EL 32.33b 28.33a 39.33a CL 41.0c 30.0a 29.0ab CL

GL 47.0a 28.33a 24.67c SCL 55.67a 18.33b 26.0b SL

NF 52.33a 16.67c 31.0cb SL 48.33b 15.33b 36.33a L

LSD (0.05) 9.6 4.3 7.11 4.61 4.61 7.69

CV% 11.59 9.72 11.64 5.12 10.65 13.99

Land uses BD/gcm3 TP (%) BD/gcm3 TP (%)

CL 1.38a 48.05b 1.34a 49.56b

EL 1.28ab 51.69a 1.18b 55.59a

GL 1.41a 46.78b 1.44a 45.53b

NF 1.21b 54.47a 1.17b 55.97a

LSD (0.05) 0.14 5.31 0.13 19.03

CV% 4.08 4.04 5.51 5.15

cmol(+) kg-1 cmol(+) kg-1

Land uses pH (H2O) EA Ex. Al Ex. H PAS pH (H2O) EA Ex. Al Ex. H PAS

CL 4.80b 3.80ab 2.82a 0.98b 45.96a 5.0b 3.4ab 2.54b 0.86a 26.53a

EL 4.87b 5.25a 3.29a 1.96a 34.19a 4.93b 4.91a 3.91a 0.99 a 37.45a

GL 5.53a 2.04cb 1.06b 0.88b 9.69b 5.53a 2.27cb 1.29bc 0.97a 11.09b

NF 5.67a 1.06c 0.30b 0.76b 5.18b 5.63a 1.29c 0.27c 1.03a 6.24b

LSD (0.05) 0.27 1.96 1.58 0.73 12.73 0.27 1.52 1.35 0.77ns 12.41

CV% 2.71 24.2 24.78 26.0 18.46 2.68 27.23 25.79 22.51 13.79

Meq/100g soil Meq/100g soil

Ca Mg Na K Ca Mg Na K

CL 3.33b 0.69b 0.25b 0.23b 7.67cb 2.09b 0.09b 0.26c

EL 6.0b 3.33b 0.19b 0.44b 4.33c 3.0b 0.10b 0.73b

GL 10.0a 7.33a 0.63a 1.07a 9.0ab 7.67a 0.43a 1.29a

NF 11.0 a 7.33a 0.36b 0.99a 12.33a 6.0a 0.32a 0.74a

LSD (0.05) 3.92 3.01 0.26 0.52 3.77 2.54 0.17 0.32

CV% 27.45 14.27 19.45 20.71 24.00 17.75 18.29 17.71

N.B. The mean values in the table that are followed by the same letter are not significantly different from each other at P < 0.05,

GL= grazing land, CL= cultivation land, EL= Eucalyptus land, NF= Natural forest, CV= Coefficient of variation, LSD= least

significant difference, EA= exchangeable acidity, Ex. Al= exchangeable Al, Ex. H= exchangeable H, PAS=Percentage acid

saturation.

The possible reason why the BD was higher in GL

and CL as compared to NF and EL could be attributed

to the compaction effect of livestock during free

grazing, deforestation, and consequent tillage

practices that might have resulted in worsening soil

structure, which in turn leads to soil compaction

(Muche et al., 2015). The lowest soil OM available in

the cultivation land can also subsidize the highest BD.

In addition to this, the current finding is in line with

Wakene and Heluf (2003), who stated that the highest

BD detected in unrestricted land was caused by soil

compaction and deprivation of OM. According to

ratings by Hazelton and Murphy (2007), soil BD is

rated as very low (<1 g/cm3), low (1-1.3 g/cm3),

medium (1.3-1.6 g/cm3), high (1.6 -1.9 g/cm3) and

very high (>1.9 g/cm3).

Aliyu Nesru et al Ethiop.J.Sci.Sustain.Dev., Vol. 10 (1), 2023

Table 2. Mean values of selected soil chemical properties.

Land uses Berchernamocheya kebele Badnayegor kebele

Meq/100g soil Meq/100g soil

TEB ECEC CEC PBS TEB ECEC CEC PBS

CL 4.51c 8.31c 24.28c 18.57c 10.12b 13.52b 28.07b 36.22a

EL 9.96b 15.22b 30.03b 33.17b 8.17b 13.08b 32.67b 26.33a

GL 19.03a 21.08a 30.13b 63.16a 18.39a 20.66a 42.07a 43.71a

NF 19.65a 20.71a 35.0a 56.49a 19.39a 20.68a 43.27a 44.81a

LSD (0.05) 2.87 2.67 3.67 10.39 4.09 4.17 7.90 23.08ns

CV% 11.48 8.69 6.49 12.94 15.51 13.03 11.49 23.33

(mg kg-1) cmol(+) kg-1 (mgKg-1) cmol(+) kg-1

Land uses Av.P OC OM TN C: N Av. P OC OM TN C: N

CL 1.09c 1.35c 2.33c 0.14b 9.59ab 1.36b 1.40d 2.42d 0.20b 7.19b

EL 0.32d 2.17b 3.77b 0.24b 9.02ab 0.63b 2.47c 4.27c 0.21b 11.56a

GL 2.54a 1.55c 2.69c 0.21b 6.29b 2.37a 3.37b 5.78b 0.46a 7.37b

NF 1.77b 5.93a 10.2a 0.51a 11.71a 2.50a 5.47a 9.40 a 0.50a 10.9a

LSD (0.05) 0.59 0.57 0.99 0.11 4.07 0.80 0.45 0.78 0.05 1.93

CV% 18.05 10.94 11.12 20.79 17.02 17.81 7.55 7.59 8.24 11.08

Land uses BpH LRSMP t/ha LREA t/ha BpH LRSMP t/ha LREA t/ha

CL 5.63a 11.3a 5.1ab 5.73c 10.2a 4.55ab

EL 5.80a 9.7a 6.7a 5.80cb 9.5ab 5.72a

GL 6.17a 6.0a 2.8cb 6.10ab 6.6cb 3.29cb

NF 6.33a 4.7a 1.3c 6.40a 4.1c 1.5c

LSD (0.05) 0.74 7.1 2.58 0.33 3.02 1.9

CV% 4.73 24.15 17.41 2.92 21.1

N.B. Means within a column followed by the same letter are not significantly different from each other at P < 0.05, BpH = Buffer

pH, LRSMP= Lime requirement determination method as Shoemaker, McLean, and Pratt, LREA= Lime requirement

determination method by extraction of exchange acidity, Av. P= Available P, OC= Organic carbon, OM= Organic Matter, TN=

total N, PBS= percentage base saturation, CEC= Cation exchange capacity, TEB= total exchangeable bases, ECEC= effective

cation exchange capacity, ns = non-significant.

Soil total porosity (TP) is a signal of the degree of

compaction in the soil. Analysis of variance reveals

significant (P < 0.01) differences in TP among land uses

for Badnayegor and Berchernamocheya kebeles. The

highest TP (54.47% and 55.97%) was detected in

natural forest land followed by EL (51.69 and 55.59 %).

In contrast, the lowest mean values (46.78% and

45.53%) of TP were registered under grazing lands

followed by CL (48.05% and 49.56%) for

Berchernamocheya and Badnayegor kebeles,

respectively (Table 1). Alterations in TP among land

uses might be due to high soil OM and lowest BD of

natural forest lands and low OM content and high

compaction due to the flattening effect of livestock

during unrestricted foraging in grazing land. Factors that

affect BD have also a direct effect on TP.

The results of the current study are in agreement with

Gebrelibanos and Mohammed (2013), who asserted that

the high TP in the soil of natural forests is accredited to

higher OM, as TP is affected by the level of soil OM and

BD (Habtamu et al. 2014). According to the ranking of

FAO (2006), soil TP (< 2%) was classified as very

low,(5-10%) low, (10-15%) medium, (15-40%) high,

and ( > 40%) very high. Based on this rating, the TP of

Aliyu Nesru et al Ethiop.J.Sci.Sustain.Dev., Vol. 10 (1), 2023

all land uses was found to be very high (> 40%). Higher

TP implies better aggregation and provides good

aeration for microorganisms and an opportunity for crop

production.

3.3.Soil chemical parameters

Soil pH was highly significantly (P < 0.01) affected

by land uses. Comparison of the mean pH value of

cultivation and eucalyptus lands with grazing and

natural forest lands indicates statistically significant

differences in Berchernamocheya and Badnayegor

kebeles. However, there were no significant differences

between EL and CL as well as between GL and NF lands

of the two kebeles (Table 1). Relatively the highest

(5.67) and the lowest (4.8) pH were documented in the

natural forest and CL of Berchernamocheya kebele

respectively. On the other hand, relatively the highest

(5.63) and the lowest (4.93) pH were verified under the

natural forest and EL of Badnayegor kebele respectively

(Table 1). Low pH in CL and EL could be due to high

tillage frequency and high rates of annual rainfall that

resulted in different forms of soil erosion, removal of

plant residues after harvesting of plants, and leaching of

basic cations. The current findings are consistent with

previous findings that indicate soil pH was significantly

lower in the soil of CL when compared to uncultivated

soils (Malo et al., 2005). Consistent with the current

study, Gebeyaw (2015) also observed a significant

alteration in pH value among land uses and showed

lower pH in the soil of cultivation land. According to

Jones (2003), soil pH rated for Berchernamocheya

kebele, mean pH for CL, EL, GL, and NF were

respectively, 4.80, 4.87, 5.53, and 5.67 and the rating

ranged from very strong acid for CL to moderate acid

for NF. Similarly, for soil pH rating for Badnayegor

kebele, the mean pH value for CL, EL, GL, and NF was

respectively 5.0, 4.93, 5.53, and 5.63, and rating ranges

from very strongly acidic for CL to moderate acidic soil

for NF (Table 1).

3.4.Exchangeable acidity (EA) and Percent Acid

saturation (PAS)

The analysis of variance revealed EA and PAS

varied highly significantly (P < 0.01) through land uses

in both kebeles. The mean EA values for CL, EL GL,

and NF lands were (3.8, 5.25, 2.04, and 1.06 cmol(+) kg-

1), and (3.4, 4.91, 2.27, and 1.29 cmol (+) kg-1) for

Berchernamocheya and Badnayegor kebeles,

respectively (Table 1). The highest EA value was

attained from EL (5.25 cmol (+) kg-1) and (4.91 cmol (+)

kg-1) and the lowest EA value was acquired from NF

lands (1.06 cmol (+) kg-1) and (1.29 cmol (+) kg-1) for

Berchernamocheya & Badnayegor kebeles, respectively

(Table 1). The mean PAS values for cultivated land, EL,

GL, and NF land were (45.96, 34.19, 9.69, and 5.18

cmol (+) kg-1) and (26.53, 37.45, 11.09, and 6.24 cmol

(+) kg-1) for Berchernamocheya and Badnayegor

kebeles respectively (Table 1). The highest PAS value

was achieved from cultivation land the PAS (45.96 cmol

(+) kg-1) and the lowest (5.18 cmol (+) kg-1) value was

achieved from NF land of Berchernamocheya kebele.

Likewise, the highest PAS attained from EL (37.45

cmol (+) kg-1) and the lowest (6.24 cmol (+) kg-1) PAS

value was achieved from NF land of Badnayegor kebele.

3.5.Exchangeable bases

The analysis of variance depicted that mean values

of exchangeable cations (Ca2+, Mg2+, Na+, and K+) were

highly significantly (P < 0.01) different across land uses

for Badnayegor kebele while Ca2+ and Mg2+ and Na+

and K+ were highly significantly (P < 0.01 and P < 0.05

respectively) diverse for Berchernamocheya kebele. The

highest mean values of exchangeable bases Ca2+ and

Mg2+ (11.0 and 7.33) were recorded in the soil of NF

land and Na+ and K+ (0.63 and 1.07) were recorded in

the soil of GL. The lowest mean values of exchangeable

bases Ca2+, Mg2+, and K+ (3.33, 0.69, and 0.23) were

recorded in the soil of CL, and Na+ (0.19) was recorded

under eucalyptus land for Berchernamocheya kebele,

respectively. Similarly, the highest mean values of

exchangeable cations Ca2+ (12.33) in NF land and Mg2+,

Na+, and K+ (7.67, 0.43, and 1.29) were registered under

GL, whereas the lowest mean values of exchangeable

cation Ca2+ (4.33) were registered under Eucalyptus

land, and Mg2+, Na, and K+ (2.09, 0.09 and 0.26) were

recorded under CL for Badnayegor kebele respectively

(Table 1). The relatively high exchangeable (Ca2+ and

Mg2+) observed in soils of NF land might be due to the

presence of relatively higher soil OM and low exposure

to soil erosion under NF lands. However, lower

exchangeable Ca2+ and Mg2+ were observed in soils of

CL and EL soils, which resulted from lower pH and soil

OM as well as due to continuous removal of Ca2+ and

Mg2+ with crop harvest from topsoil. The present

Aliyu Nesru et al Ethiop.J.Sci.Sustain.Dev., Vol. 10 (1), 2023

finding was in covenant with Aboytu (2019) who

showed that soil acidification limits the availability of

essential nutrients from the top soils. The impact of high

soil acidification results in a deficiency of available Ca,

P, and Mo and domination of soluble Al, Mn, and other

acid-forming metallic ions (Getachew & Sommer,

2000).

3.6.Cation exchange capacity and percent base

saturation

The analysis of variance revealed that soil CEC was

highly significantly (P < 0.01) affected by land uses at

the two kebeles. Accordingly, the highest (35.0 cmol (+)

kg-1) CEC value was observed in NF soil, followed by

GL (30.13), while the lowest (24.28) in CL soil,

followed by EL (30.03) for Berchernamocheya kebele.

The highest (43.27) CEC value was observed in NF land

soil, followed by GL (42.07), whereas the lowest

(28.07) was recorded in CL, followed by EL (32.67) for

Badnayegor kebele (Table 2). A possible reason for the

highest and lowest CEC in NF land and CL respectively

might be due to high soil OM in FL land but low level

of OM and high leaching of basic cations from

cultivation land. This finding was in agreement with the

findings of Bore & Bedadi (2015), who stated that the

decline in soil properties is mainly due to the

transformation of native forest and range land into

cultivated land. According to Hazelton and Murphy

(2007), the CEC of soils in CL was medium (24.28) &

high (28.07) for Berchernamocheya and Badnayegor

kebeles respectively; CEC in EL soil was high for both

kebeles. High CEC was revealed in grazing land (30.03)

and NF land (35.0) for Berchernamocheya, and very high

CEC was confirmed in grazing land (42.07) & NF land

(43.27) for Badnayegor kebeles (Table 2).

The value of PBS showed a highly significant

(p<0.01) difference amongst land uses in

Berchernamocheya kebele. However, it showed an

insignificant (p > 0.05) difference among land uses in

Badnayegor kebele. Likewise, numerical variations

were observed among the four land uses. Relatively, the

highest PBS (63.24%) was observed in grazing land,

followed by NF land (56.49%), while the lowest PBS

(18.57%) was recorded in CL, followed by EL (33.17%)

in Berchernamocheya kebele. The reason for the high

PBS content in grazing land in this kebele is probably

due to the high total exchangeable bases (TEB) content

noted in GL, while the low PBS documented in CL is

probably due to the presence of a lower level of total

exchangeable bases (TEB) observed in CL, low pH

values and soil OM and removal of basic nutrients from

topsoil by erosion and crop harvest for the

Berchernamocheya kebele (Table 2). The findings of the

current study agree with the findings of Jobira (2018)

and Kedir (2015), who reported that the highest PBS

(57.87%) was measured in GL soil, whereas the lowest

(31.23%) was recorded in CL soil.

3.7.Soil organic matter, total N, C: N ratio and

available P

The analysis of variance showed that soil OM was

very highly significantly (P < 0.001) affected by land

uses in both kebeles. The highest (10.2 %) and (9.40%)

SOM were documented in the soil of NF land, while

relatively lowest (2.33 %) and (2.42%) SOM were

recorded in the soil of CL for Berchernamocheya and

Badnayegor kebeles, respectively. The mean value of

SOM increased from CL to GL, EL, and NF lands and

from CL to EL, GL, and NF land at Berchernamocheya

and Badnayegor kebeles, respectively (Table 2). The

highest soil OM recorded in the NF land is due to the

fall of plant biomass like leaves, barks, limbs, and other

remaining plants and low exposure to soil. Conversely,

the lower SOM of CL is probably due to the removal of

SOM through oxidation, which is resulted from the

mismanagement of cultivated land triggered by

intensive cultivation and soil erosion, which then leads

to the washout of soil OM. According to Tekalign et al.,

(1991), (< 0.86) OM is rated as very low, (0.86-2.59 %)

low, (2.59-5.17%) medium/moderate, and > (5.17%)

high. Based on this rating, the OM for CL, GL

Eucalyptus plantation land, and NF land in

Berchernamocheya kebele were 2.33%, 2.69%, 3.77%,

and 10.2% respectively. The mean values of SOM for

Badnayegor kebele were 2.42%, 4.27%, 5.78%, and

9.40% in CL, EP, GL, and NF land respectively. The

result indicated that SOM was low under CL of both

kebeles, medium under Eucalyptus and GL, and high

under NF lands of both kebeles (Table 2).

The total N was very highly significantly (P < 0.001)

affected by different land uses in both kebeles. The

highest mean values (0.51% and 0.50%) of the TN were

Aliyu Nesru et al Ethiop.J.Sci.Sustain.Dev., Vol. 10 (1), 2023

documented in NF lands, while the lowest (0.14% and

0.20%) were noted in CL of Berchernamocheya and

Badnayegor kebeles respectively (Table 2). This might

be due to comparatively high SOM content noted in

natural FL and low SOM content in CL as well as due

to land use change from natural FL to CL, which may

trigger the decline of TN content. This result is

congruent with the findings of (Dawit et al., 2002).

Based on the rating suggested by Barber (1984), the TN

content recorded in CL was low for both kebeles,

medium in grazing and EL lands in Berchernamocheya

kebele and eucalyptus land in Badnayegor kebele, and

very high in NF lands at both kebeles (Table 2). The

result of the C: N ratio showed significant (P<0.05) and

highly significant (P<0.01) variations amongst land uses

in Berchernamocheya and Badnayegor kebeles,

respectively (Table 2). The highest (11.71) C: N was

noted in NF land, followed by CL (9.59), while the

relatively lowest (6.29) C: N was documented in GL,

followed by EL (9.02) in Berchernamochya kebele.

Similarly, the highest (11.56) C: N was documented in

EL, followed by NF land (10.9), while the lowest (7.19)

C: N was observed in CL, followed by GL (7.37) in

Badnayegor kebele (Table 2). Low input of SOC,

removal of crop residues from CL, and overgrazing are

probably the reasons for a low level of C: N in CL and

GL, whereas higher C: N is probably due to higher

contents of soil OC and high plant biomass in natural

FL. Similarly, previous findings also stated that narrow

C: N at the surface soils of CL is probably due to higher

microbial activity in the surface 0-20 cm soil layer

(Chimdi, 2014). Based on the ratings by Hazelton and

Murphy (2007), we have found out that except for

natural FL, which was low C: N, for all the remaining

land, uses, the C: N was rated as very low at grazing and

CL in Berchernamocheya kebele, low at the EP land and

natural FL in Badnayegor kebele (Table 2).

Available P was highly significantly (P<0.01)

affected by land uses in both kebeles. Relatively, the soil

under grazing land was documented with the highest

available P (2.54 mg/kg), followed by NF land and CL

(1.77 and 1.09mg/kg) respectively; the lowest

(0.32mg/kg) was noted in EL in Berchernamocheya

kebele. On the other hand, the highest available P was

noted (2.50 mg/ kg) in NF land, followed by grazing and

CL (2.37 and 1.36 mg/kg) respectively, and the lowest

(0.63 mg/kg) was registered in EL in Badnayegor

kebele. This result agrees with the finding of Tessema

(2008), who reported that low available P in acid soils is

due to the inherently high P fixing capacity of the soil.

As rated by Barber (1984), the available P was

qualifying very low in all land uses in both kebeles;

however, it is numerically better in soils of NF land and

GL of both kebeles (Table 2).

3.8.Lime requirement(LR) determination with the

SMP buffer solution method

The amount of lime required by using the buffer

solution method of lime requirement determination

(LR_SMP) of the experimental soil was highly

significantly (P < 0.01) affected by land uses at

Badnayegor kebele; however, it is insignificantly affected

by land uses at Berchernamocheya kebele (Table 2).

Accordingly, the highest (10.2 t/ha) value of LR was noted

in CL soil, followed by EP land (9.5 t/ha), while the lowest

(4.1 t/ha) was documented in NF land soil, followed by GL

(6.6 t/ha) at Badnayegor kebele. A possible reason for the

highest quantity of LR verified in CL and EL is probably

due to lower OM content, low pH values, relative existence

of substantial quantity of Al and H ions, and low level of

basic nutrients. However, a lower quantity of LR was

documented in NF and GL soil is probably due to relatively

higher OM content, high pH (above 5.5), and high quantity

of basic nutrients. The quantity of lime requirement

determined by using buffer solution method of lime

requirement determination SMP methods to change the

current pH value of soils to targeted pH 6.5 was in line with

the finding, CL and GL required 14.0 - 15.90 ton/ha of lime

to change the soil from 5.13-6.5 by SMP buffer solution

method (Birhanu, 2008).

3.9.Lime requirement determination with

exchangeable acidity method

The mean values of LR evaluated using the extraction

of exchange acidity method were highly significantly (P <

0.01) affected by different land uses in both kebeles. The

study revealed the highest (6.7 and 5.72) t/ha mean value

of LR in EL soil, followed by CL (5.1 and 4.55) t/ha, and

the lowest (1.3 and 1.5) t/ha in NF land, followed by GL

(2.8 and 3.29) t/ha in Berchernamocheya and Badnayegor

kebeles, respectively (Table 2). A possible reason for the

difference in LR among land uses is probably due to high

Aliyu Nesru et al Ethiop.J.Sci.Sustain.Dev., Vol. 10 (1), 2023

OM, high pH values, and lower amount of exchangeable

acidic cation (Al+ and H+). Low acid saturation was

recorded in NF land and GL in the study area requires a

relatively low quantity of lime. However, soils under CL

and EL require a high quantity of lime probably due to low

OM content, lower pH values, a relatively higher quantity

of acidic cation (Al+ and H+), and high acid saturation. This

means that when the soils contain a substantial value of

acidic cations, a higher quantity of lime is required to

reclaim soil acidity (Desalegn et al., 2017).

3.10. Comparison of lime requirement

determination methods

Of the two lime requirement determination methods

stated above, lime requirement determination by using

the buffer solution method (LR_SMP) was

exaggerated (4.1 t/ha to 11.3 t/ha) across the land uses.

However, in lime requirement by using the extraction

of exchangeable acidity method, the quantity of lime

required ranged from 1.3 t/ha to 6.7 t/ha across land

uses for the study area. The quantity of lime required

by using the extraction of exchangeable acidity method

was very low for NF lands (1.3 t, 1.5 t) and GL (2.8 t,

3.29 t) as compared to the amount of lime required by

using the buffer solution method, where the quantity of

lime required for NF lands (4.7 t, 4.1 t) and grazing

lands (6.0 t, 6.6 t) was very high for Berchernamocheya

and Badnayegor kebeles respectively. Similarly, the

quantity of lime required by using the extraction of

exchangeable acidity method was very low for CL (5.1

t, 4.55 t) and EL (6.7 t, 5.72 t) as compared to the

quantity of lime required by using the buffer solution

method for CL (11.3 t, 10.2 t) and EL (9.7 t, 9.5 t), which

was very high for Berchernamocheya and Badnayegor

kebeles respectively (Table 2). Although lime requirement

can be determined both through SMP buffer and

exchangeable acidity methods, a more suitable method

should be identified by validating it under field conditions.

4. Conclusion

The assessment of soil acidity in four land uses

showed that very low soil pH (4.8 and 4.87), (5.0 and

4.93); and higher acid saturation (45.96% and 34.2%),

(26.53 and 37.45) were recorded in CL and EL for

Berchernamocheya and Badnayegor kebeles,

respectively. The findings of the study also indicated

overall variation and loss of soil fertility in CL and EL as

compared to NF land and GL. Accordingly, CL and EL

soils were also poor in macronutrient contents and fell

below TEB (from 4.51 to 13.52), CEC (from 24.28 to

32.67), and PBS (from18.57% to 33.17%). However,

relatively higher soil pH (>5.5) and lower acid saturation

(from 5.1% to 11.09%) in NF land and GL soils indicated

its suitability for better available nutrients. The TEB

ranged from (19.03 to 19.65); CEC from (30.13 to 43.27)

and PBS from (43.71% to 63.16%) were recorded in the

soil of NF land and GL. Based on the evaluation of lime

requirement under the four land uses, we have observed

that the quantity of lime required varies greatly among

land uses. This variation is probably due to low pH values

in CL and EL soils, which require a higher quantity of

lime than adjacent NF land and GL. Finally, this soil

acidity and reduction of basic cations lead to the

intensification of risks to agricultural productivity.

Immediate and integrated land management interventions

are required to overcome soil acidity, improve soil

productivity, and achieve viable agricultural crop

production. . Application of agricultural lime and organic

fertilizers is considered a dominant measure for such

acidified cultivated land. Finally, we recommended that

further studies are needed on lime recommendation rates

in the study area based on locational field experiments.

Acknowledgments

The authors would like to acknowledge Wolkite Town

Administration for financial support and Wolkite Soil

Testing Center for providing us with materials and

supporting us in soil analysis.

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