Effects of compost, mycorrhiza, manure and fertilizer on some physical properties of a Chromoxerert soil

Effects of compost, mycorrhiza, manure and fertilizer on some physical properties of a Chromoxerert soil field experiment was conducted to explore the role of mycorrhizal inoculation and organic fertilizers on the alteration of physical properties of a semiarid Mediterranean soil (Entic Chromoxerert, Arik clayloam soil). From 1995 to 1999, wheat (Triticum aestivum L.), pepper (Capsicum annuum L.), maize (Zea mays L.

Effects of compost, mycorrhiza, manure and fertilizer

on some physical properties of a Chromoxerert soil

I Celika,∗, I Ortasa, S Kilicb

aDepartment of Soil Science, Faculty of Agriculture, Cukurova University, Adana, Turkey

bDepartment of Soil Science, Faculty of Agriculture, Mustafa Kemal University, Antakya, Turkey

Received 20 September 2002; received in revised form 27 January 2004; accepted 2 February 2004

Abstract

Addition of organic materials of various origins to soil has been one of the most common rehabilitation practices to im-prove soil physical properties Mycorrhiza has been known to play a significant role in forming stable soil aggregates In this study, a 5-year field experiment was conducted to explore the role of mycorrhizal inoculation and organic fertilizers on the alteration of physical properties of a semi-arid Mediterranean soil (Entic Chromoxerert, Arik clay-loam soil) From 1995

to 1999, wheat (Triticum aestivum L.), pepper (Capsicum annuum L.), maize (Zea mays L.) and wheat were sequentially

planted with one of five fertilizers: (1) control, (2) inorganic (160–26–83 kg N–P–K ha−1), (3) compost at 25 t ha−1, (4) farm

manure at 25 t ha−1and (5) mycorrhiza-inoculated compost at 10 t ha−1 Soil physical properties were significantly affected

by organic fertilizers For soil depths of 0–15 and 15–30 cm, mean weight diameter (MWD) was highest under the manure treatment while total porosity and saturated hydraulic conductivity were highest under the compost treatment For a soil depth

of 0–15 cm, the compost and manure-treated plots significantly decreased soil bulk density and increased soil organic matter concentration compared with other treatments Compost and manure treatments increased available water content (AWC) of soils by 86 and 56%, respectively The effect of inorganic fertilizer treatment on most soil physical properties was insignificant (P > 0.05) compared with the control Mycorrhizal inoculation + compost was more effective in improving soil physical

properties than the inorganic treatment Organic fertilizer sources were shown to have major positive effects on soil physical properties

© 2004 Elsevier B.V All rights reserved

Keywords: Soil aggregation; Soil physical properties; Soil organic matter; Compost; Manure; Mineral fertilization; Mycorrhiza

1 Introduction

It has been shown that addition of organic

mat-ter improved soil properties such as aggregation,

water-holding capacity, hydraulic conductivity, bulk

density, the degree of compaction, fertility and

resis-tance to water and wind erosion (Carter and Stewart,

∗Corresponding author Tel.:+90-322-338-6084;

fax: +90-322-338-6643.

E-mail address: icelik@mail.cu.edu.tr (I Celik).

1996; Zebarth et al., 1999; Franzluebbers, 2002) Generally, crop residues, manures, turfs, forest under story leaf falls, and compost from organic wastes have been used to increase soil organic matter (SOM) content and accordingly to improve soil physical properties in croplands (Stratton et al., 1995) Generally, fertile soils have a relatively high struc-ture stability index and percentage Improvement in soil aggregation by organic matter addition positively affects the germination of seeds, and the growth and development of plant roots and shoots (Van Noordwijk 0167-1987/$ – see front matter © 2004 Elsevier B.V All rights reserved.

doi:10.1016/j.still.2004.02.012

et al., 1993) Plant roots, root hair, mycorrhizae and

fungal hyphae play a significant role by binding

agents within and between aggregates (Tisdall, 1994;

Ortas, 2002) In the rhizosphere, mycorrhizal

hy-phae may contribute further to the aggregating effect

as they grow into small pores and bind soil

parti-cles together (Miller and Jastrow, 1990).Sutton and

Sheppard (1976)found that aggregation of sand-dune

soil by mycorrhiza treatment was five times greater

than that of sandy soil particles without mycorrhiza

treatment Bearden and Petersen (2000) reported

that mycorrhiza played a significant role in the

for-mation of aggregates and aggregate stability of a

Vertisol

Recent studies have shown that soil particles are

bound not only by mycorrhiza hyphae but also by

mycorrhizal polysaccharide (Tisdall, 1994; Smith

and Read, 1997) Water-stable soil aggregates were

correlated positively with root and arbiscular

myc-orrhizae soil mycelium development (Bethlenfalvay

et al., 1999) Mycorrhiza have also benefited soil

ecology, soil rehabilitation, and erosion control by

stimulating soil aggregation (Abbott et al., 1992;

Ortas, 2002) Recently, a strong correlation was shown

between aggregate stability and glomalin, a

glycopro-tein produced by hyphae of arbuscular mycorrhizal

fungi (Wright and Upadhyaya, 1998) Schreiner

and Bethlenfalvay (1995) reviewed the effect of

mycorrhizal fungi on aggregate formation and soil

structure

Since soil management systems influence soil

phys-ical fertility, it is important to determine the effect

of long-term organic and inorganic fertilizer

amend-ments on soil physical properties such as aggregation,

porosity and water-holding capacity In the related

lit-erature, effects of separately applied organic matter on

soil properties were studied In this study, combined

effects of organic manure and mycorrhiza were

in-vestigated Therefore, the objective of this study was

to assess if long-term organic fertilization and

myc-Table 1

Selected physical and chemical properties of soil

Soil depth (cm) Clay (%) Silt (%) Sand (%) Organic matter (%) CaCO3 (%) pH (1:2.5) Total salt (%)

orrhizal inoculation could improve some soil physical properties under semi-arid Mediterranean soil condi-tions

2 Materials and methods

2.1 Study area

The field study was carried out at the Agricultural Experimental Station of Çukurova University, Adana,

in southern Turkey, where the prevailing climate is Mediterranean with a long-term mean annual temper-ature of 18–19◦C During the experiment from 1995

to 1999 the annual mean temperature was 18.6◦C, and

relative humidity was 66% Long-term mean annual precipitation is around 650 mm, about 75% of which falls during the winter and spring (November–May), but during the experiment from 1995 to 1999 the an-nual mean precipitation was 622 mm Long-term mean annual potential evapotranspiration is 1500 mm per year (Aydin and Huwe, 1993)

The experiment was carried out on an Arik clay-loam soil, which was classified as an Entic Chromoxerert (Soil Survey Staff, 1994) Some se-lected properties of the soil at the beginning of the experiment in 1995 are given inTable 1

2.2 Preparation of compost and mycorrhizal inoculum

Compost used in the experiment was prepared ac-cording to the method described byRynk (1992) The compost was made from a mixture of grasses, stub-bles and plant leaves with equal ratio for 8 months under atmospheric conditions The inoculum (mixture

of sand+ soil + spores + hyphae) was produced in

pots using sorghum (Sorghum bicolor L.) host plants

(Ortas, 1996) Before sowing the sorghum seeds, a cocktail mycorrhizal inoculum was mixed with the

compost material Approximately 1000 spores/plant

were calculated for the total number of plants per

hectare

2.3 Field experiment

The study was conducted in 15 plots in a

randomized-block design with three replications,

dur-ing 1995–1999 The plot dimensions were 10 m wide

and 20 m long

The treatments were (1) control (CO); (2)

traditional N–P–K fertilizers (160 kg N ha−1 as

(NH4)2SO4, 83 kg K ha−1as K2SO4, and 26 kg P ha−1

as 3Ca(H2PO4)2·H2O) (F); (3) compost at 25 t ha−1

(C25); (4) farm manure (cattle) at 25 t ha−1 (M25)

and (5) mycorrhiza-inoculated compost at 10 t ha−1

(C10+MZ) The sequence of annual crops since 1995

was wheat (Triticum aestivum L.), pepper (Capsicum

annuum L.), maize (Zea mays L.) and wheat.

For each plot, a moldboard plough to 30 cm depth

was used for soil tillage after each harvesting time

An-nually, the organic fertilizers (M25, C25, C10+ MZ)

were homogenously spread out on the soil surface

in September and incorporated with a discharrow to

a depth of 12–15 cm Field cultivation to a depth of

20–22 cm was made to prepare a smooth seedbed

be-fore sowing Similar procedures were followed for the

control and fertilizer plots

2.4 Soil sampling and analyses

Before soil sampling, each plot was divided into

two equal subplots Disturbed and undisturbed soil

samples were taken from the center of each subplot

at depths of 0–15 and 15–30 cm in June 1999,

imme-diately after the harvest of the last wheat crop For

aggregate analysis, approximately 3 kg disturbed soil

samples were taken The samples were air-dried

and sieved through 4 and 8 mm sieves Undisturbed

Table 2

Physical and chemical properties of compost and manure used in the experiment

Material Organic matter

(g kg −1) pH (1:2.5) Electrical conductivity(1:2.5) (dS m−1) Total (g kg

−1)

soil samples were taken by using a steel cylinder

of 100 cm3 volume (5 cm in diameter, and 5 cm in height) Bulk density, total porosity, saturated hy-draulic conductivity and field capacity were deter-mined from undisturbed soil samples Organic matter concentration and wilting point were determined us-ing disturbed soil samples sieved through a 2 mm meshed utensil Dry bulk density was measured by the core method (Blake and Hartge, 1986), porosity was determined according to Danielson and Sutherland (1986), saturated hydraulic conductivity was deter-mined by the falling-head method (Klute and Dirksen,

1986) and particle size distribution was determined

by the Bouyoucos hydrometer method (Bouyoucos,

1962) Organic matter concentration, calcium carbon-ate, pH, and total salt were all determined according

to Page et al (1982) Some properties of the com-post and manure were determined according toPage

et al (1982)and data are given inTable 2 Plant roots were collected at the end of the wheat harvest in June

1999 for measurement of mycorrhizal root infection Mycorrhizal roots were stained according to Koske and Gemma (1989), and examined for the presence and degree of mycorrhizal infection (Gioannetti and Mosse, 1980)

Water retention capacity at −33 kPa (field capac-ity) was measured in the undisturbed soil samples and

at−1500 kPa (permanent wilting point) in disturbed samples Available water content (AWC) was then de-termined taking the difference between water retained

at−33 and −1500 kPa (Klute, 1986) Total porosity was determined in undisturbed water-saturated sam-ples of 100 cm3assuming no air trapped in the pores and its validity checked using dry bulk density and average particle density (2.65 g cm−3) values

Micro-porosity (consisting of pores with equivalent radius

<4.5 ␮m) was determined from the volumetric

wa-ter content, using a pressure membrane apparatus at field capacity Macroporosity (consisting of pores with

equivalent radius >4.5␮m) was calculated as the

dif-ference between total porosity and microporosity

A wet sieving method was used to determine the

mean weight diameter (MWD) as an index of soil

aggregation The wet sieving method ofKemper and

Rosenau (1986)was used with a set of sieves of 4, 2,

1, and 0.5 mm diameters After the soil samples were

passed through an 8 mm sieve, approximately 50 g of

the soil was put on the first sieve of the set and

gen-tly moistened to avoid a sudden rupture of aggregates

Once the soil had been moistened, the set was sieved

in distilled water at 30 oscillations per minute With

10 min of oscillation, the soil remaining on each sieve

was dried, and then sand and aggregates were

sepa-rated (Gee and Bauder, 1986) The mean weight

di-ameter was calculated as follows:

i=1

X i W i

where MWD is the mean weight diameter of water

stable aggregates, X i is the mean diameter of each

size fraction (mm) and W i is the proportion of the

total sample mass in the corresponding size fraction

after the mass of stones deducted (upon dispersion and

passing through the same sieve)

2.5 Statistical analysis

Data were analyzed using the Statistical Analysis

System (SAS, 1988) One-way analysis of variance

for each depth (0–15 and 15–30 cm) was performed

to find the effects of treatments on soil physical

prop-erties, and the least significance difference test was

used to establish if differences in the treatments were

significant atP ≤ 0.05.

3 Results and discussions

3.1 Porosity

Soil porosity was significantly (P < 0.05) affected

by the treatments and was the highest in the

com-post treatment Mycorrhiza-inoculated comcom-post and

fertilizer treatments had similar effects on total soil

porosity, while the effect of manure treatment was

less pronounced than that of compost (Fig 1) For the

soil depth of 0–15 cm, when compared with the con-trol plots, compost increased total porosity by 24%, while manure increased total porosity by about 18% (Fig 1a)

For the soil depth of 15–30 cm, the highest total porosity of 0.521 cm3cm−3 was obtained with

com-post; whereas the lowest values were from the con-trol (0.396 cm3cm−3) and fertilizer (0.403 cm3cm−3)

treated plots (Fig 1b)

The organic treatments had positive effects on mi-croporosity compared with control and fertilizer treat-ments at each soil depth Similar results were found by

Aggelides and Londra (2000)who determined that or-ganic compost application considerably improved soil physical properties by increasing total porosity and changing distribution of pore sizes in loamy and clay textured soils.Marinari et al (2000) also found that total soil porosity increased with organic fertilizers and compost, depending on the amount of materials applied

3.2 Dry bulk density, organic matter, and saturated hydraulic conductivity

Statistically significant lower bulk density (P <

0.05) was found in compost (1.17 g cm−3) and manure

(1.24 g cm−3) plots at a depth of 0–15 cm compared

with fertilizer (1.47 g cm−3) and control (1.46 g cm−3)

treatments (Fig 2a) At a depth of 15–30 cm, con-trol (1.60 g cm−3) and fertilizer (1.58 g cm−3)

treat-ments had greater values than the compost treatment (1.27 g cm−3) (Fig 2b) In all cases, bulk density at

0–15 cm was lower than at 15–30 cm This may be due

to higher soil organic matter concentration in the top layer (Paul and Clark, 1996; Nyakatawa et al., 2001) and higher compaction in the sub-surface layer due to cultivation and mass of the soil above (Ghuman and Sur, 2001) Bulk density depends on soil structure and

is an indicator of soil compaction, aeration and de-velopment ease of roots, especially in soils with high clay contents

Similarly, soil organic matter concentration was higher in the compost and manure plots than other treatments (Fig 2a and b) Soil organic matter con-centration at 0–15 cm was higher than at 15–30 cm Addition of organic fertilizers had a mild positive effect at a depth of 0–15 cm compared with control and fertilizer treatments, but no effect at a depth

Fig 1 Effect of treatments on soil porosity at depth of 0–15 cm (a) and 15–30 cm (b) CO: control, F: mineral fertilizer (N–P–K), C25: compost, M25: manure, C10 + MZ: compost + mycorrhizae inoculation Means for treatments in the same porosity class and soil depth followed by the same letter are not significantly different (P ≤ 0.05).

of 15–30 cm Mean temperature was high during

the dominant precipitation period (November–May),

which may have stimulated decomposition of organic

matter

Bulk density decreased with increasing organic

mat-ter sources such as compost, manure and mycorrhizal

inoculation Although it was not clearly observed in

the mycorrhizal treatment, the organic matter

amend-ments generally increased soil organic matter

concen-tration leading to a decrease in bulk density These

results are supported by other studies (Zebarth et al.,

1999; Aggelides and Londra, 2000)

Saturated hydraulic conductivity was higher under

compost and manure than under control and

fertil-izer treatments, due to the possible stimulating effect

on soil aggregation At a depth of 0–15 cm compared

to the control, compost increased saturated hydraulic

conductivity from 0.80 to 2.62 cm h−1(Fig 2a) At a

depth of 15–30 cm, saturated hydraulic conductivity

was 0.76 cm h−1 for the control and 1.78 cm h−1 for

the compost treatment (Fig 2b)

One of the reasons for the different effects of

treat-ments on saturated hydraulic conductivity may be

related to soil porosity, in particular macroporosity, where soils with high macroporosity generally give higher saturated hydraulic conductivity values Thus, the compost and manure treatments increased hy-draulic conductivity significantly with an increase in porosity (Figs 1 and 2) The concurrent increase in total soil porosity and hydraulic conductivity due to organic materials added into the soil is also supported

by other studies (Mathers and Stewart, 1980) Accord-ing to Franzluebbers (2002), soil organic matter is a key attribute of soil quality that impacts soil aggrega-tion and accordingly increases water infiltraaggrega-tion Soil compaction commonly results in a decline in macrop-orosity, higher susceptibility to erosion, and decreased hydraulic conductivity (Spaans et al., 1989)

3.3 Aggregation

Soil aggregation, represented by MWD, was sig-nificantly (P < 0.05) affected by the treatments At

a depth of 0–15 cm, the highest value of MWD was found for the organically amended treatments, while the lowest MWD occurred in control and fertilizer

Fig 2 Effect of treatments on soil organic matter content, dry bulk density and saturated hydraulic conductivity at depth of 0–15 cm (a) and 15–30 cm (b) CO: control, F: mineral fertilizer (N–P–K), C25: compost, M25: manure, C10 +MZ: compost+mycorrhizae inoculation Means for treatments in the same soil property and soil depth followed by the same letter are not significantly different (P ≤ 0.05).

treated plots (Fig 3a) At a depth of 15–30 cm, the

highest value of MWD was measured with manure

treatment (0.37 mm), and the lowest for the control

and fertilizer treatment (Fig 3b)

Fig 3 Effect of treatments on soil aggregation as measured by mean weight diameter at depth of 0–15 cm (a) and 15–30 cm (b) CO: control, F: mineral fertilizer (N–P–K), C25: compost, F25: manure, C10 + MZ: compost + mycorrhizae inoculation Means for treatments

in the same soil depth followed by the same letter are not significantly different (P ≤ 0.05).

Although the amount of compost applied to the soil was less in the mycorrhiza-inoculated compost than the compost application itself, mycorrhizal addition had the same effect on soil aggregation.Schreiner and

Bethlenfalvay (1995), Bearden and Petersen (2000)

and Miller (2000)showed a strong effect of

mycor-rhizal fungi on aggregate formation and soil structure

Bethlenfalvay et al (1999)reported that water-stable

soil aggregates were positively correlated with root

and mycorrhiza infection Furthermore, the work of

Wright and Upadhyaya (1998)showed that there is a

strong correlation between aggregate stability and

glo-malin, a glycoprotein produced by hyphae of

arbuscu-lar mycorrhizal fungi Mycorrhizal fungi were stated

to be a powerful component in soil environments and

soil sustainability especially for soil quality (Ortas,

2002)

The control treatment had the lowest mycorrhizal

infection (16%), and the mycorrhizal treatment had

the highest root colonization (56%) Fertilizer, manure

and compost had 23, 31 and 35% root infections,

re-spectively Since glomalin and hypha were not

mea-sured, it was not valid to make any comment on their

effect on soil aggregation Treatments with higher

my-corrhizal root infections corresponded to treatments

with higher soil aggregation

The fertilizer treatment did not have any effect on

soil aggregation compared with the control at each

depth (Fig 3a and b) Although the highest soil

or-Fig 4 Effect of treatments on soil water characteristics at depth of 0–15 cm (a) and 15–30 cm (b) CO: control, F: mineral fertilizer (N–P–K), C25: compost, M25: manure, C10 + MZ: compost + mycorrhizae inoculation Means for treatments in the same soil property and soil depth followed by the same letter are not significantly different (P ≤ 0.05).

ganic matter concentration was found in the compost treatment, the highest soil aggregation value was found in the manure treatment.Albiach et al (2001)

stated that compost application increased soil organic matter concentration but did not affect soil aggre-gate stability Kenneth and Jones (1988) argued that the increase in aggregate stability due to municipal waste compost was not significant and occurred in

a transient state Other studies indicated that short application duration of waste compost might account for this sort of response together with the addition of organic material increasing soil organic matter con-centration and in turn, aggregate stability (Pikul and Allmaras, 1986; Tisdall, 1991, 1994; Aggelides and Londra, 2000; Nyamangara et al., 2001) Similarly,

Aoyama et al (1999) showed that manure only and

a combination of manure+ N–P–K fertilizers caused significant increases in soil organic matter storage and the formation of water-stable aggregates, but N–P–K fertilizers alone did not affect these properties

3.4 Water retention capacity

The effect of organic treatments on water holding capacity was significant (P < 0.05) The compost

treatment resulted in the highest values in both field

capacity and AWC Our study also indicated that

com-post and manure treatments had a significant effect

on field capacity and AWC compared with fertilizer

treatment

In 0–15 cm depth, the highest AWC was

mea-sured with compost and manure applications and

the lowest AWC was for the control treatment

At a depth of 15–30 cm, the highest AWC was

0.173 cm3cm−3 in the compost treatment and the

lowest was 0.09 cm3cm−3 in the control treatment

(Fig 4a and b)

The effects of compost and manure on AWC were

related to increases in microporosity and

macroporos-ity Water retention capacity of soils with high porosity

was higher than the soils with low porosity.Aggelides

and Londra (2000)determined that porosity and water

retention capacity of loamy and clay soils increased

with application of compost.Nyamangara et al (2001)

determined that cattle manure application improved

soil water retention capacity However, Haynes and

Naidu (1998) concluded from a range of data that,

since water content at both field capacity and wilting

point was generally increased by additions of manure

applications, AWC was not greatly changed

4 Conclusions

Soil physical properties can be greatly affected by

the additions of organic amendments

Mycorrhiza-inoculated compost had equivalent effects on

poros-ity, organic matter, hydraulic conductivporos-ity, and MWD

as did other organic amendments applied at higher

rates The reason for this effect, despite the relatively

small amount of compost in the mixture, is due to

role of mycorrhiza on soil structure formation

High SOM concentration and soil porosity were

positively correlated with high hydraulic conductivity

and water retention capacity To a significant degree

soil bulk density decreased with organic amendments

The treatments that significantly increased SOM

con-centration were also the ones that decreased bulk

density Although the positive effect of SOM on soil

aggregation is well known, this study did not identify

a strong relationship between these two properties

However, it is suggested that organic materials should

be prepared from the lignin-rich materials to have

long lasting effect in soil This study indicates the eco-logical importance of organic materials, even when applied annually in relatively moderate quantities, for the improvement of soil physical properties

Acknowledgements

The authors would like to thank the Çukurova Uni-versity Research Fund for providing financial support-ing for project number ZF/2000/15 We also would like to thank Dr F Evrendilek, Prof Dr M Aydin,

Dr G Erpul and Dr A Tuli for their review of the manuscript

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