Wheat yield and soil properties reveal legacy effects of artificial erosion and amendments on a dryland Dark Brown Chernozem

Abstract

Erosion leads to substantial loss of soil productivity. To abate such decline, amendments such as manure or fertilizer have been successfully employed. However, the longevities of erosion and soil amendment legacy effects are not well quantified. In 1957, a Dark Brown Chernozem soil at Lethbridge, AB, was land-levelled, creating three degrees of topsoil removal or erosion: noneroded, moderate erosion, or severe erosion. Two amendment studies (1980–1985 and 1987–1991) were superimposed on the erosion treatments. Both studies were cropped to spring wheat (Triticum aestivum L.) from 1993–2010 to examine legacy effects of erosion and soil amendments on wheat yield and soil properties. Without amendment, mean wheat yield under moderate erosion was 40% of the noneroded treatment, whereas severe erosion was 34% of the noneroded treatment, 36–42 yr (1993–1999) after erosion. Under moderate or severe erosion, the restorative power of manure diminished substantially in the first 10–15 yr following cessation of addition, but then levelled off resulting in wheat yields up to 35% higher than equivalent nonamended treatments. Legacy effects of erosion (54 yr) and amendment (27–31 yr) on soil organic carbon and total nitrogen were also observed.

Short‐term legacy effects of feedlot manure application on soil mesofauna

“…This was consistent with previous findings on this same field experiment that found shortterm legacy effects on water-extractable organic C (Miller, Owen, Hao, Drury, & Chanasyk, 2019c), soil macronutrient supply (Miller et al, 2019a), and earthworms (Miller et al, 2017). Long-term legacy effects of feedlot manure have also been reported for various soil properties (Benke et al, 2008;Eghball et al, 2004;Hao et al, 2008;Indraratne et al, 2009;Larney & Olson, 2018;Larney et al, 2011Larney et al, , 2016Zhang et al, 2018). McLauchlan (2006) reported that the length of time for which organic amendments are applied to the soil is much shorter than the duration of elevated SOC and that the longevity of the legacy depends on the magnitude of the alteration.…”

“…Discontinuation of long-term application of feedlot manure to cropland may result in short-term, unquantified legacy effects on soil mesofauna. Soil mesofauna such as Acari (mites) and Collembola (springtails) can enhance microbial activity, control decomposition of organic matter, increase soil respiration and nutrient mineralization, increase carbon (C) sequestration, improve Larney, Janzen, & Olson, 2011, 2016Larney & Olson, 2018;Zhang et al, 2018). Legacy effects of manure on soil persist because of gradual decomposition of soil organic matter and slow release of nutrients and from greater inputs of crop residues from higher yields, especially during the years that manure was applied (Larney, Li, Janzen, Angers, & Olson, 2016).…”

“…Discontinuation of long-term application of feedlot manure to cropland may result in short-term, unquantified legacy effects on soil mesofauna. Soil mesofauna such as Acari (mites) and Collembola (springtails) can enhance microbial activity, control decomposition of organic matter, increase soil respiration and nutrient mineralization, increase carbon (C) sequestration, improve Larney, Janzen, & Olson, 2011, 2016Larney & Olson, 2018;Zhang et al, 2018).…”

Assessing Impacts on the Natural Resource Soil in Life Cycle Assessment: Methods for Compaction and Water Erosion

“…Long-term experiments (16 years) showed short-term losses for soil removal of 15 and 20 cm and seemingly permanent losses for all removal depths . Even longer-term data for similar experiments at the same site shows that legacy effects erosion were still measurable on wheat yield 53 years after soil removal . For all these experiments, soil was removed to depths of 5–20 cm, corresponding to 750–3000 t ha –1 soil loss (assuming a bulk density of 1.5 t m –3 ).…”

Assessing legacy effects of a 12‐year irrigated cropping systems study with a post‐hoc bioassay

“…The objective was to use dry bean as a post‐hoc field bioassay, to capture and assess the legacy effects of 12 yr of CONV vs. CONS soil management and crop rotation histories. Legacy effects (Larney & Olson, 2018) or soil memory (Janzen, 2016) describe the persistence of past land use actions that have now ceased. Field bioassays have been used to assess legacy effects of other long‐term studies.…”