Organic Soil Amendment and Tillage Affect Soil Quality and Plant Performance in Simulated Residential Landscapes

Abstract

<jats:p>The urban soil environment is usually not conducive to healthy root growth and function, leading to problems with plant establishment, growth, and aesthetic quality. The objective of this study was to determine if the addition of compost with or without the application of shallow tillage or aeration will improve soil physical and chemical properties and plant growth compared with an unamended control in simulated new residential landscapes. Twenty-four mixed landscape plots were established in a randomized complete block design to simulate new residential landscapes. Each plot was constructed using 10 cm of subsoil fill material over a compacted field soil and planted with <jats:italic>Stenotaphrum secundatum</jats:italic> and mixed ornamental plant species. Composted dairy manure solids were applied as an organic soil amendment at a depth of 5 cm (≈256 Mg·ha<jats:sup>−1</jats:sup>) in combination with two mechanical soil treatments (tillage to 15 cm and plug aeration) for a total of five soil management treatments plus an untreated control. Soil physical and chemical properties, plant growth, and quality and plant tissue nutrient concentrations were assessed periodically to determine the effect of soil treatment on soil and plant quality. Applications of compost to soils significantly reduced soil bulk density and pH and increased soil organic matter, electrical conductivity, and Mehlich-1 phosphorus and potassium concentrations. All ornamental plant species, with the exception of <jats:italic>Raphiolepis indica</jats:italic> (L.) Lindl. ex Ker Gawl., exhibited more growth when grown in soils amended with composted dairy manure solids. In most instances, plant tissue nitrogen and phosphorus concentrations were higher for plants grown in soils receiving compost. Results of our study suggested that the addition of composted dairy manure solids to soils can improve soil properties and enhance plant growth in residential landscapes when sandy fill soils are used. In contrast, shallow tillage and aeration had little effect on soil properties or plant growth.</jats:p>

Influence of Organic and Inorganic Soil Amendments on Soil pH and Macronutrients

“…The findings of this study agrees with those of Goyal et al [13] who reported an increase in the total soil nitrogen after application of both the organic and inorganic amendments in the cropping field. Both organic and inorganic amendments contributes to an increased supply of key mineral nutrients like nitrogen hence making them available in the soils as reported by Loper et al [14]. This study results also agree with findings of Wuest and Gollany (CM) treatment led to the highest increase of N (recording 0.40 %).…”

Below ground matters: Urban soil rehabilitation increases tree canopy and speeds establishment

“…Soil organic amendments are commonly recommended for improving highly disturbed urban 432 soils and are particularly recommended for reducing soil compaction (Cogger, 2005;Saebø and 433 Ferrini, 2006;Larney and Angers, 2012;Sloan et al, 2012). While organic soil amendments 434 immediately decrease ρ b through a bulk dilution of mineral soil with organic material (Bassuk and Rivenshield, 2007;Loper et al, 2010), the persistence of this effect has been questioned. In 436 the Arlington study, the small decreases in ρ b were likely due to this dilution effect, as aggregate formation usually takes longer than the 13 months between installation and sampling (Wick et al, 438 2009a).…”

Soil Physicochemical Properties Variation in Black Soil after the Long-term Application of Different Organic Amendments

“…This was due to the liming and buffering effect of CACO3 in cow manure [47,48]. Moreover, the nature of amendments affects the pH, thus if the applied amendment has a low pH, it will affect the pH of the soil and vice versa [49]. The high pH in the organic amended fields could have been due to any of the under mentioned mechanisms or combinations; proton consumption during the removal of carboxyl groups from the organic acids anions which occur during decomposition [50], proton consumption by functional groups associated with the organic materials [51] and the release of hydroxide ions from local anaerobic microsites during reduction reactions [52].…”