Positive ions that are available in soils absorb on grain surfaces. The total sum of cations that can be absorbed bij a soil/sediment at a certain PH is defined by the cation-exchange capacity (CEC, in meq g-1: mol equivalents per gram). The uptake of cations is an important parameter in agriculture and the larger the CEC, the more cations can be absorbed to the soil. The CEC depends highly on the pH of soil and sediments, where the CEC decreases with decreasing PH (increasing acidity). The exchange of ions on sediments occurs commonly fast on geological time scales, but the kinetics of adsorption in natural environments is still poorly understood. The strength of the bonding between the cations and the sediments varies from weak Van der Waals bondings (physical adsorption) to strong chemical bonds. The CEC is widely used for agricultural assessment because it is a measure of general soil fertility as well as an indicator of structural stability because CED is capabel of enhancing development of shrinkage cracks. The list below shows the CEC for different types of minerals. The data indicate that the CEC can vary over 2 orders of magnitude for various types of , minerals and can vary one order of magnitude within one soil type. Cation exchange capacity for different types of sediment (Eisma, 1992; Locher and de Bakker, 1990):

Cation exchange capacity.

The Nature and Properties of Soils

Effect of the direct use of biomass in agricultural soil on heavy metals __ activation or immobilization

Assessment of organic amendments for improving coastal saline soil

Published in Agron. J. 104:1672–1678 (2012) Posted online 13 Sept. 2012. doi:10.2134/agronj2012.0153 Copyright © 2012 by the American Society of Agronomy, 5585 Guilford Road, Madison, WI 53711. All rights reserved. No part of this periodical may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. C one of the most important grain crops worldwide, is highly responsive to early P absorption (Miller, 2000) and P deficiency is a major constraint for its production in many low-input agro-ecosystems (Bayuelo-Jiménez et al., 2011). Phosphorus is an essential macronutrient that often limits plant growth due to its low bioavailability in soils. Enhanced P absorption depends on the extent to which roots are able to increase soil available P interception or to mobilize P from less soluble sources. Plant attributes determining the mobilization and absorption of P include root attributes, mycorrhizal associations, and rhizosphere conditions (Lambers et al., 2006). Most of these attributes can be modified by cropping practices, such as P fertilization and tillage (Hu et al., 2009; Jing et al., 2010; Miller, 2000). Repeated mineral P applications to soil increase soil P saturation level and general P fertility (Deubel et al., 2011), and this higher soil P fertility inhibits AM fungal development (Lekberg et al., 2008; Mathimaran et al., 2007; Treseder and Allen, 2002). In addition, P fertilization has been found to increase corn root length and mass (Ibrikci et al., 2009), stimulate root branching (Jing et al., 2010), and induce fine root proliferation in the fertilized soil zone (Jing et al., 2010). Beauregard et al. (2010) pointed out that tillage could modify the physical, chemical, and biological properties of a soil. Especially, the modifications in soil penetration resistance and air capacity may change soil functionality and P fertilizer requirement (Acton and Gregorich, 1995; Deubel et al., 2011). Normally, compared to no till, tillage tended to decrease AM fungal colonization in roots (Alguacil et al., 2008; Duan et al., 2010; Jasper et al., 1989; Kabir et al., 1997; McGonigle and Miller, 1996; Roldan et al., 2007) since tillage could destroy AM fungal propagules (Schalamuk and Cabello, 2010). Jansa et al. (2002, 2003) pointed out that tillage could cause a shift in AM fungal diversity. Reduced soil disturbance could favor AM fungal species richness (Boddington and Dodd, 2000), and the abundance of non-Glomus AM fungi (Jansa et al., 2002), such as Scutellospora spp. (Jansa et al., 2006). With regard to the influence of tillage on corn roots, the results are sometimes conflicting, perhaps as a result of differing conditions of the soil environment. Specifically, tillage can reduce (Hilfiker and Lowery, 1988), increase (Mosaddeghi et al., 2009; Qin et al., 2005), or have no effect (Raczkowski, 1989) on corn root length density. In addition, Qin et al. (2006) found that tillage could decrease average root diameter in corn. It was reported that corn P absorption could be modified by tillage or by P fertilization (Amusan et al., 2011; Chassot and Richner, 2002). Some studies conducted under controlled conditions indicated that the tillage-induced decrease in corn P absorption was due, at least in part, to the negative effects of tillage on the effectiveness of mycorrhizal symbiosis (Gavito and Miller, 1998; Miller, 2000). However, under field conditions, the reasons why tillage modifies corn P absorption remain unclear. Therefore, our study was performed in a long-term experiment site, which was established at an Agriculture and ABSTRACT Phosphorus deficiency is a major constraint for corn (Zea mays L.) production. Cropping practices, such as tillage, modify corn P absorption, but the underlying mechanism must be assessed. A study was conducted at a long-term (18-yr) experimental site in Quebec, Canada, to evaluate the effects of tillage and P fertilization on arbuscular mycorrhizal (AM) fungi, soil properties, root attributes, corn growth, and corn P concentration. Soil (0–10 cm) and plant samples were collected at the 8 to 10 leaf stage from plots under moldboard plow (MP) and no till (NT) fertilized with 0, 17.5, or 35 kg P ha–1. Tillage increased soil bulk density, vesicular colonization, shoot and root biomass, root surface area, average diameter, volume, total root length density, and the percentage of medium-sized roots; it decreased total soil C and N concentrations, specific root length, percentage of fine roots, and arbuscular and total AM fungal colonization. Phosphorus fertilization reduced total AM fungal colonization, enhanced soil Mehlich-3 P level, total root length density, and the percentage of fine roots. Corn shoot and root P concentrations, reduced by tillage, were positively correlated with the percentage of fine roots and arbuscular colonization, but negatively correlated with vesicular colonization and the percentage of medium-sized roots. Overall, P fertilization reduced total AM fungal colonization and increased root length density, and tillage decreased arbuscular development in roots and fine root growth in soil resulting in the low corn P concentration.

Growth of Corn Roots and Associated Arbuscular Mycorrhizae Are Affected by Long-Term Tillage and Phosphorus Fertilization

Identification of a sustainable integrated soil fertility management option in the tropics will not only salvage the degraded soils but also enhances the attainment of the goal of food security. This study was conducted in 2004 and 2005 on a degraded tropical Alfisol in south western Nigeria to evaluate the effect of legume residue, poultry manure and inorganic fertilizers on maize yield, nutrient uptake and soil properties. The treatments consisted of two rates of poultry manure (0 and 5 t ha−1), three rates of N fertilizer (0, 50 and 100 kg N ha−1 applied as urea), three rates of P fertilizer (0, 30 and 60 kg P ha−1 applied as single super phosphate) and two soybean treatments (with or without incorporation of legume residue) in various combinations as a factorial experiment in Randomized Complete Block design with three replicates. Results showed that poultry manure alone led to significant increase in maize yield (60%) and soil organic matter (45%). In contrast, legume residue incorporation gave significantly lower increase in yield (7%) and soil organic matter (11%). However, the combined application of poultry manure and legume incorporation led to 72% increase in maize yield as opposed to 63 and 10% increase recorded when manure alone or legume alone were incorporated, respectively. Optimal maize yield was achieved when manure application was integrated with P fertilizer application. The interaction of P fertilizer and legume incorporation indicated that soil phosphorus and maize P concentration were significantly increased with the application of the P fertilizer and legume incorporation. Hence, the application of P fertilizer alone is most likely to be economical compared with its integration with legume incorporation.

Effect of the integrated use of legume residue, poultry manure and inorganic fertilizers on maize yield, nutrient uptake and soil properties

Organic manures are known to be rich sources of both macro and micro nutrients of the crop. They also help in improving the physical status of the soil. Pot experiments were carried out to determine the effects of poultry manure on some soil chemical properties pH, organic C, available P, exchangeable Ca, Mg, K, Na, and Effective Cation Exchange Capacity i.e. ECEC) and dry matter yields, plant heights, concentrations of N, P and K in plant tissues of soybean plants. Five soil samples collected from research farms in Federal University of Agriculture, Abeokuta (FUNAAB), Odeda, Ayetoro, Ibadan, Ikenne in South Western Nigeria, were used for the screen house pot experiment. Treatments consisted of five rates of poultry manure (0, 2.5, 5.0, 7.5 and 10 t ha) and 100 kg ha of NPK 20:10:10 fertilizer as basal application. The pot experiments were conducted at the Research Farm of FUNAAB. Experimental design was Completely Randomised Design (CRD) with three replicate. Soybean (TGx 1448-2E) was grown for three consecutive cycles of seven weeks per cycle and both soil and plant samples were collected and analysed. Application of Original Research Article Soremi et al.; JAERI, 11(3): 1-10, 2017; Article no.JAERI.32419 2 poultry manure significantly increased organic carbon, exchangeable bases and effective cation exchange capacity in the soils, concentrations of N, P and K in plant tissue. The study concluded that application of poultry manure increased available nutrients, increased nutrient uptake and improved dry matter yield in soybean.

Effects of Poultry Manure on Some Soil Chemical Properties and Nutrient Bioavailability to Soybean

Field experiments were conducted at the Federal University of Agriculture Abeokuta, Nigeria to evaluate the changes in crop microenvironment, growth and yield performance of intercropping okra, pepper and pumpkin with cassava. The vegetables were planted sole and in mixtures with three cassava cultivars: Idileru, Odongbo and TMS30572. Intercropping reduced weed dry weight and soil temperature but increased soil moisture content, light interception and number of earthworm casts. Cassava/pumpkin intercrop increased soil moisture content, light interception and number of earthworm casts but reduced soil temperatures and weed dry weight compared with cassava/okra and cassava/pepper intercrops. Vegetative characters and fruit yields of okra, pepper and pumpkin were not affected by intercropping. Leaf area index (LAI) of intercropped cassava with pumpkin was reduced but not with okra and pepper. Land equivalent ratio was higher in cassava/okra and cassava/pepper than in cassava/pumpkin intercrop. Cassava/vegeta...

Soil temperature and moisture content changes with growth and yield of cassava/vegetable intercrops

Availability of soil phosphorus (P) is a function of its dynamics and can be improved by using organic amendments. Experiments were carried out to determine the effect of poultry manure (PM) on soil P fractions and bioavailability to soybean (Glycine max). Soils from ten farmers’ fields in Southwest Nigeria, were used for incubation and pot experiments. Treatments were five rates of PM (0, 2.5, 5.0, 7.5 and 10 t ha−1). Triplicate units in incubation and pot experiments were arranged in Completely Randomised Design. Soybean was grown for three consecutive growth cycles of seven weeks each and soil samples were analysed for Saloid P, Al-P, Fe-P, Ca-P, occluded P, reductant soluble P, and residual P. Results indicated that Fe-P was the dominant active inorganic P in the soils while residual P was the dominant inactive inorganic-P in most of the soils. In the pot experiment, application of poultry manure significantly increased organic P in the soils in the first growth cycle, but decreased slightly i...

https://tandfonline.com/doi/pdf/10.1080/09542299.2017.1287549

Speciation and dynamics of phosphorus in some organically amended soils of southwestern Nigeria

Soil contamination with heavy metals is of great concern worldwide because of its negative effects on human health and environment. The objective of this study was to evaluate the influence of poultry manure on cadmium (Cd) adsorption characteristics in soils from ten different land uses and to determine the effects of Cd adsorption on soil properties. Laboratory experiments were carried out using Cd concentrations ranging from 0 to 160 mg Cd L−1 and poultry manure rates ranging from 0 to 8% w/w basis. Results showed that all the soils exhibited varying capacity to adsorb Cd with values ranging from 28.78 to 130.2 mgkg−1; 126.2 to 153.5 mgkg−1 and 126.2 to 156.1 mgkg−1 for 0%, 4% and 8% poultry manure at 160 mgkg−1 initial Cd concentrations, respectively. Lowest Cd adsorbed (28.78 mgkg−1) was recorded in samples from 6 months fallow and highest (156.1 mgkg−1) from vegetable field. On the average, capacity to adsorb Cd was 72.1%, 99.7% and 95.3% with 0%, 4% and 8% applied poultry manure, respective...

J. G. Bodunde

Papers

Effect of the integrated use of legume residue, poultry manure and inorganic fertilizers on maize yield, nutrient uptake and soil properties

Effects of Poultry Manure on Some Soil Chemical Properties and Nutrient Bioavailability to Soybean

Soil temperature and moisture content changes with growth and yield of cassava/vegetable intercrops

Speciation and dynamics of phosphorus in some organically amended soils of southwestern Nigeria

Cadmium adsorption as influenced by poultry manure addition in soils of South-Western Nigeria