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.

Soil & Tillage Research 78 (2004) 59–67 Effects of compost, mycorrhiza, manure and fertilizer on some physical properties of a Chromoxerert soil I Celik a,∗ , I Ortas a , S Kilic b a b Department of Soil Science, Faculty of Agriculture, Cukurova University, Adana, Turkey Department of Soil Science, Faculty of Agriculture, Mustafa Kemal University, Antakya, Turkey Received 20 September 2002; received in revised form 27 January 2004; accepted February 2004 Abstract Addition of organic materials of various origins to soil has been one of the most common rehabilitation practices to improve 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−1 and (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 Introduction It has been shown that addition of organic matter improved soil properties such as aggregation, water-holding capacity, hydraulic conductivity, bulk density, the degree of compaction, fertility and resistance 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 structure 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 60 I Celik et al / Soil & Tillage Research 78 (2004) 59–67 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 hyphae may contribute further to the aggregating effect as they grow into small pores and bind soil particles 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 formation 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 mycorrhizae 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 glycoprotein 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 physical fertility, it is important to determine the effect of long-term organic and inorganic fertilizer amendments on soil physical properties such as aggregation, porosity and water-holding capacity In the related literature, effects of separately applied organic matter on soil properties were studied In this study, combined effects of organic manure and mycorrhiza were investigated Therefore, the objective of this study was to assess if long-term organic fertilization and myc- orrhizal inoculation could improve some soil physical properties under semi-arid Mediterranean soil conditions 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 temperature 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 annual 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 selected properties of the soil at the beginning of the experiment in 1995 are given in Table 2.2 Preparation of compost and mycorrhizal inoculum Compost used in the experiment was prepared according to the method described by Rynk (1992) The compost was made from a mixture of grasses, stubbles and plant leaves with equal ratio for 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 Table Selected physical and chemical properties of soil Soil depth (cm) Clay (%) Silt (%) Sand (%) Organic matter (%) CaCO3 (%) pH (1:2.5) Total salt (%) 0–15 15–30 36 38 35 37 29 25 1.6 1.4 30 33 7.6 7.8 0.06 0.06 I Celik et al / Soil & Tillage Research 78 (2004) 59–67 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, during 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 )2 SO4 , 83 kg K ha−1 as K2 SO4 , and 26 kg P ha−1 as 3Ca(H2 PO4 )2 ·H2 O) (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 Annually, 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 before 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, immediately after the harvest of the last wheat crop For aggregate analysis, approximately kg disturbed soil samples were taken The samples were air-dried and sieved through and mm sieves Undisturbed 61 soil samples were taken by using a steel cylinder of 100 cm3 volume (5 cm in diameter, and cm in height) Bulk density, total porosity, saturated hydraulic conductivity and field capacity were determined from undisturbed soil samples Organic matter concentration and wilting point were determined using disturbed soil samples sieved through a 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 determined 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 carbonate, pH, and total salt were all determined according to Page et al (1982) Some properties of the compost and manure were determined according to Page et al (1982) and data are given in Table 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 capacity) was measured in the undisturbed soil samples and at −1500 kPa (permanent wilting point) in disturbed samples Available water content (AWC) was then determined taking the difference between water retained at −33 and −1500 kPa (Klute, 1986) Total porosity was determined in undisturbed water-saturated samples of 100 cm3 assuming no air trapped in the pores and its validity checked using dry bulk density and average particle density (2.65 g cm−3 ) values Microporosity (consisting of pores with equivalent radius 4.5 ␮m) was calculated as the difference 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 of Kemper 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 mm sieve, approximately 50 g of the soil was put on the first sieve of the set and gently 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 of oscillation, the soil remaining on each sieve was dried, and then sand and aggregates were separated (Gee and Bauder, 1986) The mean weight diameter was calculated as follows: n MWD = Xi Wi i=1 where MWD is the mean weight diameter of water stable aggregates, Xi is the mean diameter of each size fraction (mm) and Wi 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 properties, and the least significance difference test was used to establish if differences in the treatments were significant at P ≤ 0.05 Results and discussions 3.1 Porosity Soil porosity was significantly (P < 0.05) affected by the treatments and was the highest in the compost treatment Mycorrhiza-inoculated compost 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 control 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 cm3 cm−3 was obtained with compost; whereas the lowest values were from the control (0.396 cm3 cm−3 ) and fertilizer (0.403 cm3 cm−3 ) treated plots (Fig 1b) The organic treatments had positive effects on microporosity compared with control and fertilizer treatments at each soil depth Similar results were found by Aggelides and Londra (2000) who determined that organic 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, control (1.60 g cm−3 ) and fertilizer (1.58 g cm−3 ) treatments 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 development 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 concentration 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 I Celik et al / Soil & Tillage Research 78 (2004) 59–67 63 Fig 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 matter sources such as compost, manure and mycorrhizal inoculation Although it was not clearly observed in the mycorrhizal treatment, the organic matter amendments generally increased soil organic matter concentration 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 fertilizer 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 treatments 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 hydraulic conductivity significantly with an increase in porosity (Figs 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) According to Franzluebbers (2002), soil organic matter is a key attribute of soil quality that impacts soil aggregation and accordingly increases water infiltration Soil compaction commonly results in a decline in macroporosity, higher susceptibility to erosion, and decreased hydraulic conductivity (Spaans et al., 1989) 3.3 Aggregation Soil aggregation, represented by MWD, was significantly (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 64 I Celik et al / Soil & Tillage Research 78 (2004) 59–67 Fig 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) 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 Fig 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) I Celik et al / Soil & Tillage Research 78 (2004) 59–67 Bethlenfalvay (1995), Bearden and Petersen (2000) and Miller (2000) showed a strong effect of mycorrhizal 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 glomalin, a glycoprotein produced by hyphae of arbuscular 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, respectively Since glomalin and hypha were not measured, it was not valid to make any comment on their effect on soil aggregation Treatments with higher mycorrhizal 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- 65 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 aggregate 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 concentration 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 Fig 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) 66 I Celik et al / Soil & Tillage Research 78 (2004) 59–67 treatment resulted in the highest values in both field capacity and AWC Our study also indicated that compost 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 measured 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 cm3 cm−3 in the compost treatment and the lowest was 0.09 cm3 cm−3 in the control treatment (Fig 4a and b) The effects of compost and manure on AWC were related to increases in microporosity and macroporosity 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 Conclusions Soil physical properties can be greatly affected by the additions of organic amendments Mycorrhizainoculated compost had equivalent effects on porosity, organic matter, hydraulic conductivity, 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 concentration 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 ecological 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 University Research Fund for providing financial supporting 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 References Abbott, L.K., Robson, A.D., Jasper, D., Gazey, C., 1992 What is the role 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Soil Sci 79, 501–504  ... 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. .. 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... 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