Effect of Integrated Use of Coffee Husk Compost and NPS Fertilizer on Soil Physicochemical Properties and Yield of Coffee

: Integrated application of inorganic and organic fertilizers is the main sources for replenishing plant nutrients in agricultural soils. However, selecting the optimum combination of these resources based on soil type and crop species is necessary. In this context, field experiment was conducted at Haru research center to assess the effect of coffee husk Compost and NPS Fertilizer on soil physicochemical properties and Yield of coffee in 2018/2019. The treatments were the different rates of both compost and NPS fertilizers laid out in randomized complete block design. Soil samples were taken before and after planting. Analytically determined soil physicochemical and agronomic data was subjected to analysis of variance using GLM procedures of the Statistical Analysis System Software (version 9.3). The results of the study showed that combined application of coffee husk compost and NPS fertilizers were improved soil moisture and total porosity over control, while, bulk density was decreased below the control. The alkalinity of applied compost caused increment of soil pH after treating the plots by coffee husk compost. Moreover, the application of coffee husk compost along with inorganic fertilizers increased the contents of organic matter, total nitrogen, available phosphorus, available sulfur, exchangeable basis and CEC. Combined application of coffee husk compost at (7.5 t ha ) and mineral 1 NPS fertilizer at (50 kg ha ) has better improved yield of coffee crop. The experimental yield of Manasibu 1 variety for present study from the station was 1.59 t ha . Therefore, based on the result of the study it can be 1 concluded that under condition of low soil pH of study area the availability of essential nutrients (e.g. P, N, K, Ca, Mg and Mo) are critically affected. This indicates that the strong acid pH values at Haru Research sub-center require more attention. Moreover, the low levels of CEC, organic carbon, total nitrogen and available P contents at study area soils confirm that soil fertility is among the constraints for sustainable coffee production in the Haru district. In response to this application of integrated NPS fertilizer and coffee husk compost with different rates improved soil physicochemical properties and coffee yield. Nevertheless, the potential coffee productivity in the area has not yet been exploited. Alleviating the soil fertility problems of the soils of study area through integrated application of local available coffee husk compost and blended NPS fertilizer could be one option. The study recommended that the use of 7.5 t ha coffee husk compost and 50 kg ha of NPS 1


INTRODUCTION worsened by continuous cropping, nutrients mining
Poor soil fertility is considered to be the major In order to improve the fertility status of the soil, constraint to increased food production in most acid soils nutrient replenishment should be done.This is always of Ethiopian high lands [1].These situations have done by applying chemical fertilizers.The use of inorganic and inadequate replacement of nutrients removed.
fertilizers believed to alleviate the problem of decline in blended fertilizers for coffee production need to be soil fertility; though it can increase crop productions for investigated as little information is available in the time being only.But coffee farm state plantation and local country.However, this research topic is still new in Haru farmers have used mainly chemical fertilizers for long time district.Such information is a particular important input which can cause degrading of soil.On the other hand, for coffee producing community and for land use planners high cost of inorganic fertilizers and other agrochemicals in planning land management practices for sustaining along with cost of transportation make their use the production and productivity of coffee at study area.uneconomical for most smallholder farmers [2].
So, there is a need to draw a mid-way between organic Similarly, Anteneh et al. [3] reported the timely and inorganic extremities that may improve soil unavailability of inorganic fertilizer and absence of credit physicochemical properties and sustain coffee crop system.To alleviate this problem of smallholder farmers yield without deteriorating soil fertility in Western with growing demands for sustainable agriculture the use Wollega; by considering the nutrient dynamics with of composting technology to excessively available coffee respect to agro ecological scenarios that would be helpful wastes (coffee husks) becoming inevitable for coffee for further amendment of nutritional status in most of the producing areas [4].coffee growing area.Keeping all these aspects in Coffee waste product is one of the wastes, producing consideration, this study was initiated to assess the effect during coffee crop production, that have been studied of combined application of coffee husk compost and NPS by recycling through conventional and vermicomposting blended fertilizers on selected soil physicochemical methods [5].The coffee crop production at Haru properties and yield of Coffee arabica in Haru research district producing a large amount of coffee-products center.(coffee husk), amounting to about 500, 000 tons per year are depositing without efficient use.However, when MATERIALS AND METHODS agricultural residues are deposited at higher doses, it could affect permeability and infiltration rate of the soils Description of the Study Area besides causing environmental pollution [6].Coffee husk Location and Area Coverage: The study was conducted is normally burnt or covered on the coffee field of local at Haru Agricultural Research Center which is located at farmers.Some farmers mix up coffee husk with manure, but a distance of 466 km from Addis Ababa within the Oromia this way showed less efficiency.Beside this, untreated National Regional State (ONRS).Haru Agricultural coffee husk will spread diseases and pets to next crop.
Research Sub-Center is found in Wara Baro Kebele Haru Currently there is a huge interest from regional and district in West Wollega Zone under Jimma Agricultural federal government to convert by products of coffee crop Research Center at latitude of 8°54'30''-9°5'30'' North and (for example coffee husk) into usable end products such longitude of 35°52'0''-36°8'0'' East.Haru district has 46, as compost [7].
451.91 ha total cultivable land and the total area of land Adding inorganic fertilizer alone is not sufficient to under cultivation at Haru Agricultural Research center is retain a sufficient soil fertility status level.Moreover, in about 76 hectares [10].degraded soil where there is little organic matter, yield response is limited, even if artificial fertilizers are being Climate and Topography: Haru agricultural research used [8].Beside this, coffee husk compost release sub-center is characterized by unimodal rainfall pattern nutrients very slowly to the plants.On other hand, with an average annual rainfall of 1700 mm.The rainy nutrient content of compost is low compared to in organic season starts in March and ends on October and dry fertilizers, so compost is usually applied at large rates.
season is November to ends on February.It has the mean Nevertheless, applying large quantity of such material is minimum and maximum temperature of 12.4 and 27.8°C, difficult in smallholder farmers.Hence, an integrated respectively [11].The center consists of sub-humid tepid approach, combining coffee husk compost and mineral to cool mid highland coffee agro-ecological zone with fertilizer is better strategy for coffee crop production [9].
altitude of 1750 meter.The topographic area of Haru However, the present blended fertilizer district is highly variable, which reflects the past recommendation did not consider the integrated soil geological and erosion process.It consists of topographic fertility management practices such as inclusion of patterns which include plateaus and steep hill slopes.organic sources.In this view, integrated nutrient More than 50% of coffee production at study area is management approaches involving coffee husk and NPS found on land with slopes greater than 16% [12].Soil Types and Geological Parent Materials: Most of x 1.2 m height was prepared.Often, several pits were dig coffee soils in the southwestern and southern region are next to each other, to allow turning from one pit into the classified as Nitisol, which are originated from highly next [17].weathered rock.Similarly, the dominant soil type in Pits were formed and filled up with the residues as per western Wollega Haru Research Sub-Center is also Nitisol composting procedures prepared by Cobo et al. [18].which was formed from weathered acidic volcanic rocks Next compost materials were stacked in pit to form a pile.parent materials [13].
The stacking was done in way to permit drainage and Population, Land Use and Farming System: The total to the top).A 20 cm layer of mixture was sprinkled with number of populations in Haru district is 93, 600 from water for adequate moisture content (50%).Sprinkle water these 12, 716 households are coffee producers (11,427 after each layer as required making the layers moist but Male and 1, 289 female).Haru district has 46, 451.91 ha not wet or soggy.Repeat the above step until your pile total cultivable land.Out of these the total land covered reaches the height of 120 cm.Forest soil was used to by coffee crop is 32, 931 ha [14].Traditional mixed crop introduce beneficial microorganisms for decomposition.livestock system that involves crop production and Cover the pit with broad leaves (like banana, enset) and animal husbandry is the predominant farming system in grasses.the study area.The main crops grown in the study area During compost processing at 21 days the materials are coffee, maize, sorghum and teff.The major livestock were mixed and turned to next pit [19].The compost was reared are cattle, poultry, sheep and goat.Inter crop, ready for use after three times turning (after 63 days) grazing and livestock production land use and traditional and after air drying [20].Good decomposition can be farming system are used in the Haru district.Oxen power detected by a pleasant odor, heat produced (this was is the main power source for ploughing and threshing even visible in the form of water vapor given off during activities in the study area. the turning of the pile), growth of white fungi on the Compost Materials and Preparation Procedures: Coffee volume and by the change in color of the materials to by products (coffee husk), farm yard manure (FYM), top brown.Finally, the composts prepared were air dried and soil, leguminous plant materials, fruit or vegetable wastes, incorporate compost to soil in the early spring at a depth stalk straw, leaves are materials that were used for of 2.5 cm-5 cm of compost into the top 7.5 cm-12.5 cm of compost preparation [15].High quality compost was soil.To determine the composition of the compost prepared from a mixture of 70% coffee pulp, 10% FYM, samples 10 g of samples were collected with four 10% leguminous plant materials and 10% top soil [16].
replicates from different spots in each pile for chemical Pit site that drain easily so the pile never site in a pool of analysis at Jimma Agricultural College of Agriculture and water was selected.Pit of the size 2 m length x 2 m width Veterinary Medicine Chemistry Research Laboratory.
ventilation (large size residues at bottom and fine residues decomposing organic material, earthy smell, reduction of  [21] and ATA [22], Soil Sampling and Preparation for Laboratory Analysis: respectively.The experiment consists of nine treatment In order to determine soil physicochemical properties, combinations and 27 experimental units (plots).The composite and undisturbed soil samples to a depth of following nine treatment combinations were evaluated.0-30 cm were randomly drawn from each experimental plot Site Selection, Field Management and Experimental composite soil sample, disturbed samples were randomly Procedures: Site selection, experimental lay out taken from five different spots across each plot from a measurement were done and plots were leveled and the depth of 0-30 cm to make one composite sample.At the land was prepared by digging the hole size of 60 cm x 60 same time, core samples from 0-30 cm depth layer were cm depth for coffee seedling transplantation.The total also collected to determine soil bulk density of each plot.experimental area and area of each plot were 0.324 ha and Soil samples were collected from the canopy of coffee 120 m , respectively.Spacing between plots and plants tree, where fertilization is usually applied [25].
2 were 3 m and 2 m, respectively.The number of stand The collected soil samples were bagged, labeled and plants per each row was 5; while per each plot were 30.
transported to the laboratory for preparation and analysis The soil samples before planting were taken to Jimma of soil properties.Sufficient amount of composite soil Agricultural Research Center laboratory for analyzes.
samples were air dried and ground to pass through a 2 mm Coffee seedling transplanting was done in 2015 using sieve in preparation for the analyses of the selected Manasibu coffee seed variety (high yielder than other physicochemical properties following standard laboratory varieties at the study area).After field transplanting of procedures [26].A portion of the disturbed soil samples coffee seedlings all agronomic practice such as hoeing, were taken and sieved using 0.5 mm diameter for the weeding and sucker pruning were done by adopting the determinations of organic matter and total nitrogen.recommended agronomic practices of coffee production.
Soil sample preparation and analysis was done at Jimma NPS blended fertilizer and compost were broad casted by Agricultural College of Agriculture and Veterinary hand and thoroughly mixed with top soil near to the area Medicine Chemistry Research Laboratory.The samples of the canopy of the coffee plant in march at beginning of were analyzed for soil texture, dry bulk density, particle rainy season [23].
density, gravimetric soil water content, pH, available P During the first year of coffee growth, no product and K, total N, organic carbon, exchangeable acidity, was yielded by coffee tree; rather the tree directed all of exchangeable basic cations (Ca2+, Mg2+, K+, Na+).its resources to develop a widely branched root system.At the end of second year, the coffee trees were partially Soil Physical Analysis: Particle size distribution was ripened and a low yield was earned, about 1.5 kg of fresh determined by the hydrometer method [27].After cherries per tree.Complete and formal yield earning was determining sand, silt and clay separates; the soil was started during the third year.At the end of third year, assigned to textural classes using the USDA soil yield and yield components were harvested and soils were textural triangle [28].Bulk density was determined using also taken from each plot and transported to Jimma the core method as described by Jamison et al. [29].
before planting and after harvesting [24].To collect Particle density ( p) was determined using pycnometer from compost samples extracted by ammonium acetate method following procedures described in Rao et al. [30].
(1N NH OAc) at pH 7.0.Exchangeable potassium and Total porosity was calculated from the values of bulk sodium were determined from extract using flame density and particle density using the method described photometer as described by Dzung et al. [45], while by Rowell [31].Soil moisture content was determined calcium and magnesium was determined by atomic using gravimetric method as described by Reynolds [32].
Chemical Analysis of Soil: Soil pH in water was Agronomic Data Collection: At Haru research center determined by the glass electrode pH meter [33] at 1:2.5 usually yield and growth parameters are collected when soils to water ratios.To determine organic carbon, wet coffee cherry is fully ripening or when it is ready for digestion method following the procedure of Walkley and picking.For coffee yields determination each cherry was Black [34] was employed.Total N content of the soil was picked at a time, collected in baskets and transferred to determined using the modified Kjeldahl procedure [35].
bags by site worker, after which it was weighed and The organic matter content of the soil was calculated by transported to wet processing.multiplying the organic carbon percentage by 1.724.

Relative amount of carbon to nitrogen was determined by
Statistical Analysis: Analytically determined soil taking the ratio of soil organic carbon to total nitrogen.physicochemical and yield data were subjected to Available P was extracted using Bray II [36].The P analysis of variance using GLM procedures of the extracted with this method was measured by Statistical Analysis System Software (version 9.3) [47].spectrophotometer following the procedures described Whenever the ANOVA detects significant differences by Murphy and Riley [37].Available sulfur (SO -S) was (P < 0.05) between treatments, mean separation was 4 determined using gravimetric determination following conducted using Fisher's Least Significant Difference test extraction with ammonium acetate (1N NH OAc) [38].[48].Simple correlation analyses were also conducted to 4 Furthermore, cation exchange capacity (CEC) and identify useful associations among key soil chemical exchangeable bases (Ca, Mg, K and Na) were determined parameters and coffee plant variables.from soil samples extracted by ammonium acetate (1N NH OAc) at pH 7.0.Exchangeable potassium and RESULTS AND DISCUSSION 4 sodium were determined from extract using flame photometer as described by Chapman [39] while calcium Physicochemical Properties of the Experimental Site Soil and magnesium was determined by atomic absorption Before Planting: The laboratory results of the selected spectrophotometer method [40].The Cation exchange physicochemical properties of the soil sample taken capacity was determined by the method described by before planting are presented in Table 2.The results Champan [41].Exchangeable acidity (exchangeable Al indicated that the soil has 37%, 24% and 39% sand, silt 3+ and H ions) was determined by saturating the soil and clay, respectively and could be categorized as clay + samples with potassium chloride solution and titrated loam textural class on the basis of Hillel [49] soil textural with sodium hydroxide as described by Mclean [42].
triangle.The particle density of the experimental area was The percent base saturation (PBS) of the soil samples was 2.65 g cm which might be due to dominance of quartz calculated by taking the ratio of the sum of the basic mineral.The result further revealed that soil pH of the exchangeable cations (Ca2+, Mg 2+ and Na+) to CEC as experimental site was 5.10 (Table 2), found in strongly percentage [43].
acidic ranges, on the basis of pH limit proposed by

Compost Sampling and Analysis:
To determine the plant growth is pH 5.50 to 6.50 [51].Nevertheless, this composition of the coffee husk compost, samples of 10 g finding showed that the pH of study area soils is out of was taken with four replicates per each pile for chemical this normal pH range.Under such condition the analysis.Compost samples was analyzed for the chemical availability of essential nutrients (for examples P, N, K, Ca, parameters such as pH, OC, total N, total P, K and sulfur Mg and Mo) are critically affected.Beside this, toxicity of contents as per standard procedures formulated by aluminum to plants greatly affects crop growth as well as Karltun et al. [44].Cation exchange capacity and nutrients absorption.Similarly, Abebe et al. [52] reported exchangeable bases (Ca, Mg, K and Na) were determined the effect of Al toxicity on crop growth at Haru area.According to the classification of soil total nitrogen (0.15%), Organic carbon (0.76%) and available P (1.04 ppm) (Table 2) suggested by Landon [53], the soils of study area are found in low range (Table 2).The average contents of basic cations (potassium (K), sodium (Na), magnesium (Mg) and calcium (Ca) in the soil were 0.02, 0.04, 2.33 and 4.56 cmol (+) kg , respectively 1 (Table 2).As per the rating set by FAO [54] the base cations of study area are classified as very low for K and Na, moderate for Mg and low for Ca.The low and very low values of basic cations at study area might be attributed to leaching of surface soils by excessive rainfall.Similarly, Kidanu and Achalu [55] reported the leaching of appreciable amounts of exchangeable basic ions like calcium (Ca), magnesium (Mg), sodium (Na) and potassium (K) from the surface of soil by excessive rainfall.
The CEC of the soil was (11.53 cmol (+) kg ) which 1 is found in low range according to Landon [56] (Table 2).The low CEC of the soil might be due to low organic matter content and high soil acidity.Soils with a low value of CEC generally have a low fertility status and a low resistance to changes in soil chemistry that could be caused by land management practices.This finding is in agreement with Amini and Mohammad [57] who reported low CEC due to low organic matter of study area soils.The C: N ratio of the study area soil was 11.61 (Table 2) and this value indicates that soil organic reserve of the area is well decomposed and mineral N can be released for coffee plant use.This finding is in agreement with Tesfaye et al. [58] who reported that C: N ratio less than Chemical Composition of Compost: Chemical composition of the compost utilized as organic source in the study area are presented in (Table 3).The results of the analysis revealed that the compost contained the mean organic carbon and total nitrogen contents of 12.48% and 1.76%, respectively, with a resultant narrow C: N ratio of about 11.73 (Table 3).The narrow carbon to nitrogen ratio in the organic nutrient source indicates that the compost is well decomposed and matured [59].The average pH (1:2.5 H O) reading of the compost was 8.96, which is alkaline in 2 reaction.The concentration of total P in the compost was 47.75 ppm.In addition to this, the average concentrations of the exchangeable bases of compost were 22.45, 9.55, 4.31 and 0.83 cmol (+) kg ) for Ca, K, Mg and Na, 1 respectively.Similarly, CEC of the compost was 41.62 (cmol (+) kg ) (Table 3). 1

Effect of Compost and NPS Fertilizer on Soil Physicochemical Properties after Planting Effect of Compost and NPS Fertilizer on Soil Physical
Properties: Bulk density, moisture content and total porosity of the post-harvest soil were presented in (Table 4).

Bulk Density:
The mean soil bulk density showed significant (P < 0.05) variation among the different treatments applied (Table 4).The maximum bulk density (1.24g.cm ) was obtained in control plots, while, the 3 lowest bulk density (1.16g.cm ) was recorded in plots 3 with 10 t coffee husks compost ha .The relatively 1 lowest bulk density recorded for plots with 10 t coffee husks compost ha might be due to organic matter effect 1 which can be evidenced by negative correlation (r = -0.30) between bulk density and organic matter (Table 7).

Similarly, Tesfaye et al.
[60] reported the inverse production.Soil organic matter was significantly (P < 0.05) relationship between soil bulk density and organic matter affected by application of NPS fertilizer and coffee content.

Porosity:
The different rates of NPS fertilizer and coffee the control treatment (Table 5).The highest soil husk compost significantly (p < 0.05) affected total organic matter (6.99%) was recorded from application porosity of soil.The maximum porosity (56.10%) was of 10 t ha coffee husk compost.Whereas, the lowest obtained from application of 10 t coffee husk compost soil organic matter (2.73%) was recorded from control ha .The minimum total porosity (53.00%) of soil was plots.The increase in soil organic matter following 1 recorded in control plot (Table 4).The highest value of application of compost might be attributed to the high total porosity from full doze of coffee husk compost ha content of organic matter in the coffee husk compost 1 might be due to corresponded higher organic matter (Table 2).In line with this, finding Tesfaye et al. [65] contents and lower bulk density values of this plot.The also reported increase in soil organic matter following finding is in agreement with Tamado and Mitiku [61] who application of filter cake compost, filter cake and vinasse reported that the highest total porosity was obtained from to soils.relatively highest FYM.
Soil Moisture Content: Soil moisture content was (P < 0.05) affected by the treatments (Table 5).The significantly (P < 0.05) affected by the different treatments highest soil total nitrogen (0.35%) was recorded applied.The maximum soil moisture content (45.60%) was from application of 10 t coffee husk compost ha .The obtained from application of 10 t coffee husk ha while, lowest soil total nitrogen (0.14%) was obtained from the 1 the minimum soil moisture content was recorded in control control plots.The highest soil total nitrogen recorded plots (39.60%) (Table 4).The maximum soil moisture from 10 t coffee husk compost ha might be due to content might be due to the presence of organic matter releasing of N from organic matter as a result of supplied to soil in optimum amount to increase soil mineralization.This can be confirmed from highly moisture content.Similarly, Islam et al. [62] reported significant positive correlation (r = 0.99) between total increment in soil water content as a result of application nitrogen and organic matter (Table 7).This finding is in of FYM.
agreement with Argaw [66] who reported direct

Effect of Compost and NPS Fertilizer on Soil Chemical carbon (OC) content. Properties Soil pH: Soil pH is the most important master chemical soil
Soil Available Phosphorus: Soil available phosphorus parameter and it reflects the overall chemical status of the soil and influences a whole range of chemical and biological processes occurring in the soils [63].Soil pH was significantly (P < 0.05) and highly affected by applied NPS and coffee husk compost (Table 5).The highest soil pH (5.58) was recorded from application of 10 t coffee husk compost ha alone followed by the application of 1 100 kg NPS ha (5.11).While, the lowest soil pH (4.92) 1 was obtained from control plot (Table 5).The result revealed improvement in soil pH by 11.82% (4.92 to 5.58) (Table 5).The increment of soil pH might be ascribed to the alkalinity of applied compost as noted from its high pH value (Table 3).Similarly, increase in soil pH due to the application of composts with high pH value was also reported by Kasongo et al. [64].
Soil Organic Matter: The use of organic materials is an important component for sustainable agricultural with various levels increased soil organic matter over 1 Soil Total Nitrogen: Total soil nitrogen was significant 1 1 association between total N content of a soil and organic was significantly (P < 0.05) affected by NPS fertilizer and coffee husk compost (Table 5).Application of 10 t ha 1 coffee husk compost gave highest available phosphorus (11.24 ppm), while, the lowest soil available phosphorus (3.56 ppm) was obtained from the control plot (Table 5).The available phosphorus recorded for compost applied plot is beyond the critical level of available P (8 mg kg ) for Ethiopian soils reported by Tekalign and 1 Haque [67].The highest available phosphorus for compost plots might be due to increased soil pH as a result of coffee husk compost rates applied than applied inorganic fertilizer.The finding is in agreement with Anwar [68] who suggested increase in available P contents as result of applied coffee husk compost.Similar study by Nduka et al.
[69] also reported that coffee husk compost could release organic substances that can form complex with ions of Fe and Al in soil solution consequently prevents phosphorus fixation.LSD = least significant difference; CV = coefficient of variation; numbers followed by the same letter in the same column are not significantly different at 5% probability level.Soil Available Sulfur: Soil available sulfur was soil pH, that reduce exchangeable acidity and significantly (P < 0.05) affected by the different treatments negatively correlated with pH (r = -0.85**)(Table 7).(Table 5).Application of 75 kg NPS ha + 5 t coffee Similarly, other researchers were reported that Soil 1 husk compost ha gave highest record (9.68 ppm) pH progressively increased while the exchangeable 1 followed by 9.41 ppm from 50 kg NPS ha +7.5 t coffee acidity decreased with increased rates of compost and 1 husk compost ha (Table 5).While, the lowest value lime [71].
1 (6.84 ppm) was recorded in control plots.This could be one indication that moderate applications of coffee Cation Exchange Capacity: The cation exchangeable husk compost and NPS fertilizer supply adequate soil capacity of the soil was showed significant (P < 0.05) sulfur levels to soil.The values of Sulfur gained from the difference with the application of NPS fertilizer and coffee treatments are consistent with recommendation by husk compost (Table 6).Maximum CEC (17.26) cmol (+) Tisdale et al. [70] which stated concentrations of 3 to 5 kg ) was obtained from application of 10 t coffee husk ppm or more SO in the soil solution is adequate for the compost ha (Table 6).While, the least CEC (10.80 cmol 4 -2 growth of many plant species.(+) kg ) of soil was gained from control plots (Table 6).
Exchangeable Acidity: The exchangeable acidity was lowest CEC of this experiment are classified as significant (P < 0.05) and affected by different between medium and low range, respectively.The increase in treatments (Table 5).The highest soil exchangeable CEC over the control might be due to the increase in OM acidity values were recorded from both application of contents and available nutrients with the applied organic 100 kg NPS ha alone (2.30 cmol (+) kg ) as well as fertilizers.This can be evidenced with positive and from the control (2.30 cmol (+) kg ) (Table 5).While, the significant correlation (r = 0.66**) between CEC and 1 least exchangeable acidity was gained from the treatment organic carbon (Table 7).Similarly, Samuel et al.
[72] of 25 kg NPS ha + 10 t coffee husk compost ha reported direct correlation between organic matter and 1 1 (1.81 cmol (+) kg ).This might be due to an increment of cation exchange capacity.As per the rating set by Landon [56], the highest and  Exchangeable Bases: The exchangeable calcium showed over the control might be due to exchangeable K released to soil through mineralization from coffee husk compost. of NPS and coffee husk compost (Table 6).Highest In line with this, Kasongo et al.
[75] reported increase in exchangeable calcium (11.10) (cmol (+) kg ) result was soil exchangeable K as a result of coffee husk compost 1 recorded from the application of 10 t coffee husk applied to tropical acid soils.compost ha , while, the lowest value (7.15 (cmol (+) The soil exchangeable sodium showed significant 1 kg ) was obtained from the control plots (Table 6).
(P < 0.05) difference with the application of NPS and 1 This increment might be due to Ca availability from coffee husk compost (Table 6).The highest soil 2+ compost applied to soil.Similarly, Asha and Devanna [73] exchangeable sodium value (0.056 cmol (+) kg ) was reported higher exchangeable Ca content supplied to obtained from 10 t ha followed by (0.053 cmol (+) kg ) 2+ soil as a result of releasing from mineralization of the from application of 100 kg ha NPS fertilizer.The lowest compost.
soil exchangeable sodium (0.039 cmol (+) kg ) was from The soil exchangeable magnesium also showed control plots.The increment of exchangeable Na over significant (P < 0.05) difference with the different the control by 10 t decomposed coffee husk ha might be treatments (Table 6).The maximum mean soil due to added (Na ) from decomposed coffee husk to soil.exchangeable magnesium (2.46

cmol (+) kg ) was
This finding is in agreement with Chaves et al. [76] who 1 recorded from the application of 10 t coffee husk reported the increment of exchangeable Na from compost ha .While the lowest exchangeable Mg value application of compost to soils.
(2.24 cmol (+) kg ) was obtained from control (Table 6). 1 This increment might be due to increase in Mg Effect of Coffee Husk Compost and NPS Fertilizer on 2+ availability through increasing pH as a result of the Yield of Coffee: The effect of NPS fertilizer and alkalinity of applied compost.This finding is in decomposed coffee husk rates showed significant agreement with Samake [74] who reported increase in (p < 0.05) difference on yields of coffee (Figure 2).The Mg in the soil as a result of applied manure and highest 1.59 t ha mean yield was obtained with the 2+ improved soil pH.application of fertilizers combined from application of 50 The soil exchangeable potassium showed significant kg NPS ha + 7.5 t coffee husk compost ha followed by (P < 0.05) difference with the application of NPS and mean 1.48 t ha clean coffee yield recorded from decomposed coffee husk to soil (Table 6).The maximum application of 75 kg NPS ha + 5 t coffee husk compost mean soil exchangeable potassium (0.94%) was recorded ha .The lowest 0.56 t ha yield was obtained from the from the application of 10 t coffee husk compost ha control without any fertilizer amendment (Figure 2).The 1 followed by 0.89% from application of 25 kg NPS ha combination of coffee husk compost at 7.5 t ha and 1 + 10 t coffee husk compost ha rate on soil.The lowest mineral NPS fertilizer at 50 kg ha application were the 1 exchangeable K value (0.42%) was obtained from highest promise for coffee yields and about 64.70% coffee + control plots (Table 6).The increase in exchangeable K yield increase over the control.The highest yield from compost integrated with NPS decreased due to application of organic fertilizer and fertilizer plot over the control might be attributed to showed a negative correlation (r = -0.22)with coffee yield extraction of large quantity of mineral nutrients of coffee (Table 7).This indicates that incorporating combination crop from sufficient available nutrients supplied to soil by of coffee husk compost and blended NPS fertilizers in the compost and blended fertilizers.Similarly, Chemura et al.
soil not only improved the nutrient status, but also [77] stated that incorporation of organic and inorganic resulted in good physical conditions of the topsoil and fertilizers improved soil physical property and nutrient thus, significantly favored optimum shoot and root availability that may have a direct effect on coffee crop growth parameters and thus, enhanced nutrient use growth and yield attributes.Combined applications of efficiency by the coffee crop with ultimate increased coffee husk compost and NPS chemical fertilizers are more coffee yield and coffee crop productions.Similarly, effective than sole application of coffee husk compost or Wairegi et al. [78] also reported that coffee yields can NPS blended fertilizers for sustainable coffee productivity only be enhanced and sustained by the addition of enhancement.
integrated form of compost and mineral fertilizers.Moreover, there was significant positive correlation among coffee yield and soil OC, total N and available CONCLUSIONS AND RECOMMENDATIONS P contents (r = 0.63**, 0.62**, 0.83**), respectively.The positive correlations among coffee yield and soil total The results of this study showed that the soil has N, available P and OC status indicates that the soil categorized as clay loam textural class.Soil pH (5.1) of nutrient status may affects coffee yield and yield the experimental site was out of normal range for coffee components directly.However, soil bulk density crop production.Fertility limiting factors such as soil organic carbon (0.76%), total nitrogen (0.15%), available REFERENCES P (1.04 ppm) and CEC (11.53 cmol (+) kg ) of the soil were 1 found in low range.The field study result revealed that combined application of coffee husk compost and NPS fertilizers were improved soil moisture and total porosity over control, while, bulk density was decreased below the control.Applying combined form of coffee husk compost at 7.5 t ha and mineral NPS fertilizer at 50 kg ha gave coffee yield of 1.59 t ha .
1 Therefore, based on the result of the study it can be concluded that under condition of low soil pH of study area the availability of essential nutrients (e.g.P, N, K, Ca, Mg and Mo) are critically affected.Beside this, toxicity of aluminum to plants greatly affects crop growth as well as nutrients absorption.This indicates that the strong acid pH values at Haru area require more attention.Moreover, the low levels of CEC, organic carbon, total nitrogen and available P contents at study area soils confirms that soil fertility is among the constraints for sustainable coffee production in the Haru district.In response to this application of integrated NPS fertilizer and coffee husk compost with different rates improved soil physicochemical properties and yield coffee crop.Nevertheless, the potential coffee productivity in the area has not yet been exploited.Alleviating the soil fertility problems of the soils of study area through integrated application of local available coffee husk compost and blended NPS fertilizer could be one option to reduce the yield gap.
Recommendation: Based on the findings and conclusions of this study the following recommendations are given: Soil management practices that can increase low soil fertility status and soil pH are important at Haru area.This study suggested that the use of 7.5 t ha coffee 1 husk compost and 50 kg ha of NPS fertilizer can be 1 the best alternative integrated soil fertility management option in place of the sole application of inorganic fertilizers at study area tentatively.Nevertheless, in order to give conclusive recommendation further research studies are needed for more soil types and coffee crop varieties.
Effect of Integrated Use of Coffee Husk Compost and NPS Fertilizer on Soil Physicochemical Properties and Yield of Coffee (Coffea arabica L.) at Haru Research Center, Western Ethiopia Gemechu Chali and Tesfaye Wakgari

Fig. 1 :
Fig. 1: Location map of study area (Arc GIS, 2018) capacity; C: N = carbon to nitrogen ration; pH = power of hydrogen exchange capacity: Ca = Calcium: Mg: Magnesium: K = Potassium: Na = Sodium: PBS= Percent of Base Saturation, Numbers Followed by same letter in the same column are not significantly different at 5 % probability level

1 Fig. 2 :
Fig. 2: Effects of compost and NPS fertilizer on coffee yields

Table 1 :
Treatment combinations and their ratesTreatmentTreatment combinations (coffee husk compost in t ha + NPS in kg ha , respectively)

Table 3 :
Mean values of compost chemical properties

Table 4 :
Effect of compost and NPS Fertilizer on selected soil physical properties

Table 5 :
Mean value of some soil chemical properties as affected by NPS and compost of coffee husk EA= Exchangeable acidity; TN= total nitrogen; Ava.p= available phosphorous; Ava.S= Available sulfur; Mean values within a row or column followed by the same letter(s) are not significantly different from each other at P 0.05.

Table 6 :
Mean value of soil CEC, exchangeable bases (Ca, Mg, K and Na) and PBS as affected by NPS and compost

Table 7 :
Pearson correlation coefficients among some soil chemical properties, yield and Growth parameters