Plant-assisted bioremediation: Soil recovery and energy from biomass

AbstractNortheastern Thailand relies on agriculture as a major economic activity, and has used high levels of agrochemicals due to low facility, and salty sandy soil. To support soil recovery and sustainable agriculture, local farmers have used organic fertilizers from farmed animal feces. However, knowledge about these animal fecal manures remains minimal restricting their optimal use. Specifically, while bacteria are important for soil and plant growth, an abundance and a diversity of bacterial composition in these animal fecal manures have not been reported to allow selection and adjustment for a more effective organic fertilizer. This study thereby utilized metagenomics combined with 16S rRNA gene quantitative PCR (qPCR) and sequencing to analyze quantitative microbiota profiles in association with nutrients (N, P, K), organic matters, and the other physiochemical properties, of the commonly used earthworm manure and other manures from livestock animals (including breed and feeding diet variations) in the region. Unlike the other manures, the earthworm manure demonstrated more favorable nutrient profiles and physiochemical properties for forming fertile soil. Despite low total microbial biomass, the microbiota were enriched with maximal OTUs and Chao richness, and no plant pathogenic bacteria were found based on the VFDB database. The microbial metabolic potentials supported functions to promote crop growth, such as C, N and P cyclings, xenobiotic degradation, and synthesis of bioactive compounds. Pearson’s correlation analyses indicated that the quantitative microbiota of the earthworm manure were clustered in the same direction as N, and conductivity, salinity, and water content were essential to control the microbiota of animal manures.

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Earthworms as an Ecological Indicator of Soil Recovery after Mechanized Logging Operations in Mixed Beech Forests

Forests ◽

10.3390/f12010018 ◽

2020 ◽

Vol 12 (1) ◽

pp. 18

Author(s):

Hadi Sohrabi ◽

Meghdad Jourgholami ◽

Mohammad Jafari ◽

Farzam Tavankar ◽

Rachele Venanzi ◽

...

Keyword(s):

Soil Properties ◽

Soil Depth ◽

Biological Properties ◽

Economic Benefits ◽

Ecological Indicator ◽

Traffic Intensity ◽

Soil Biological Properties ◽

Density And Biomass ◽

Soil Recovery ◽

The Impact

Soil damage caused by logging operations conducted to obtain and maximize economic benefits has been established as having long-term effects on forest soil quality and productivity. However, a comprehensive study of the impact of logging operations on earthworms as a criterion for soil recovery has never been conducted in the Hyrcanian forests of Iran. The aim of this study was to determine the changes in soil biological properties (earthworm density and biomass) and its recovery process under the influence of traffic intensity, slope and soil depth in various intervals according to age after logging operations. Soil properties were compared among abandoned skid trails with different ages (i.e., 3, 10, 20, and 25 years) and an undisturbed area. The results showed that earthworm density and biomass in the high traffic intensity and slope class of 20–30% at the 10–20 cm depth of the soil had the lowest value compared to the other treatments. Twenty-five years after the logging operations, the earthworm density at soil depth of 0–10 and 10–20 cm was 28.4% (0.48 ind. m−2) and 38.6% (0.35 ind. m−2), which were less than those of the undisturbed area, respectively. Meanwhile, the earthworm biomass at a soil depth of 0–10 and 10–20 cm was 30.5% (2.05 mg m−2) and 40.5% (1.54 mg m−2) less than the values of the undisturbed area, respectively. The earthworm density and biomass were positively correlated with total porosity, organic carbon and nitrogen content, while negatively correlated with soil bulk density and C/N ratio. According to the results, 25 years after logging operations, the earthworm density and biomass on the skid trails were recovered, but they were significantly different with the undisturbed area. Therefore, full recovery of soil biological properties (i.e., earthworm density and biomass) takes more than 25 years. The conclusions of our study reveal that the effects of logging operations on soil properties are of great significance, and our understanding of the mechanism of soil change and recovery demand that harvesting operations be extensively and properly implemented.

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Evaluation of Leaf Litter Mulching and Incorporation on Skid Trails for the Recovery of Soil Physico-Chemical and Biological Properties of Mixed Broadleaved Forests

Land ◽

10.3390/land10060625 ◽

2021 ◽

Vol 10 (6) ◽

pp. 625

Author(s):

Meghdad Jourgholami ◽

Azadeh Khoramizadeh ◽

Angela Lo Monaco ◽

Rachele Venanzi ◽

Francesco Latterini ◽

...

Keyword(s):

Soil Properties ◽

Soil Compaction ◽

Biological Properties ◽

Soil Protection ◽

Natural Soil ◽

Compacted Soils ◽

Beneficial Effects ◽

Physico Chemical ◽

Forest Logging ◽

Soil Recovery

Engineering applications can be used to mitigate the adverse effects of soil compaction and amend compacted soils. Previous literature has highlighted the beneficial effects of interventions such as litter mulching and incorporation on skid trails. However, little is known about the effectiveness of these alternatives in restoring forest soil quality after forest logging. The objective of this study was to properly elucidate the effects of the above mentioned soil protection methods, litter incorporation before skidding (LI) and litter mulching after skidding (LM), on the recovery of compacted soil’s physico-chemical and biological properties on skid trails over a 2-year period in the Hyrcanian forests of Iran to identify the best option for restoration intervention. The litter used in both methods consisted of dried leaves of the hornbeam and maple tree in three intensities of 3, 6, and 9 Mg ha−1. The results showed that the application of both methods (LI and LM) significantly improved the soil properties when compared to the untreated skid trail. Results showed that the recovery values of soil properties in the LI treatments were significantly higher than those of the LM. The recovery values of soil properties by 6 and 9 Mg ha−1 were significantly higher than those of 3 Mg ha−1, while the differences were not significant between 6 and 9 Mg ha−1. Our findings showed that soil properties were partially recovered (70–80%) over a 2-year period from treatment, compared to untreated, but the full recovery of soil properties required more time to return to the pre-harvest value. Overall, the results of this study demonstrated that the application of soil protection methods accelerates the process of recovering soil properties much faster than natural soil recovery, which can take more than 20 years in these forests.

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The Microbial Community of Landfill Soils and the Influence of Landfill Gas on Soil Recovery and Revegetation

Contaminated Soil ’90 ◽

10.1007/978-94-011-3270-1_69 ◽

1990 ◽

pp. 315-316

Author(s):

Sharon D. Wigfull ◽

Paul Birch

Keyword(s):

Microbial Community ◽

Landfill Gas ◽

Soil Recovery

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Fate of applied urea 15N in a soil-maize system as affected by urease inhibitor and nitrification inhibitor

Plant Soil and Environment ◽

10.17221/129/2009-pse ◽

2010 ◽

Vol 56 (No. 1) ◽

pp. 8-15 ◽

Cited By ~ 16

Author(s):

L. Zhang ◽

Z. Wu ◽

Y. Jiang ◽

L. Chen ◽

Y. Song ◽

...

Keyword(s):

Nitrification Inhibitor ◽

Maize Yield ◽

Application Rate ◽

Environmental Benefits ◽

N Recovery ◽

Urease Inhibitor ◽

N Application ◽

Maize Production ◽

Normal Maize ◽

Soil Recovery

A micro-plot field experiment with reduced urea 15N application was conducted to study the effects of urease inhibitor NBPT (N-(n-butyl) thiophosphoric triamide) and nitrification inhibitor DMPP(3,4-dimethyl-1H-pyrazolium dihydrogen) on the fate of applied urea 15N; it aimed to find an efficient way to reduce the urea N application rate while improving the agronomic and environmental benefits. Five treatments were installed, i.e., 180 kg N/ha (N1, conventional application rate), 126 kg N/ha (N2, reduced to 70% conventional application rate), N2 + NBPT, N2 + DMPP, and N2 + NBPT + DMPP. Compared with treatment N1, all the other treatments had a significantly higher total 15N recovery by both soil and plant (P < 0.05 48.20, 41.39, 37.69, 38.85 and 34.83% soil recovery for N2 + NBPT + DMPP, N2 + DMPP, N2 + NBPT, N2 and N1treatment, respectively; and 42.68, 40.86, 40.25, 37.18 and 36.30% plant recovery for N2 + NBPT + DMPP, N2 + DMPP, N2 + NBPT, N2, and N1 treatment, respectively). In the plant 15N recovery, the 15N absorbed in grain/stem was highest in treatment N2 + NBPT + DMPP. The maize biomass and the maize yield had a slight increase in treatment N2 + NBPT + DMPP, compared with those in treatment N1. In sum, for the maize production in study area, N2 + NBPT + DMPP application method would be a feasible way to ensure the normal maize yield while improving yield quality, saving urea fertilizer, and protecting the environment.

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Evolution of the Residual Pollution in Soils after Bioremediation Treatments

Applied Sciences ◽

10.3390/app10031006 ◽

2020 ◽

Vol 10 (3) ◽

pp. 1006 ◽

Cited By ~ 2

Author(s):

Rocío Pastor-Jáuregui ◽

Mario Paniagua-López ◽

Javier Martínez-Garzón ◽

Francisco Martín-Peinado ◽

Manuel Sierra-Aragón

Keyword(s):

Lactuca Sativa ◽

Root Elongation ◽

Total Concentration ◽

Potential Toxicity ◽

Affected Area ◽

X Ray ◽

Lactuca Sativa L ◽

Caco3 Content ◽

Soil Recovery ◽

Potential Mobility

This study is focused on one of the most important spills that ever happened in Europe, the Aznalcóllar’s mine spill. The extensive application of phytostabilization in the area led to the implementation of the Guadiamar Green Corridor (GGC). Soil physicochemical properties were analyzed and the total concentration of Pb, As, Zn and Cu was measured by X-ray fluorescence (XRF); bioassay using Lactuca sativa L. was applied to assess potential toxicity. Two decades after the accident, some soils affected by residual contamination continue to appear in the area. According to regulatory levels, Pb and As concentrations are exceeded in around 13%and 70%, respectively, in the uppermost part of the soils (first 10 cm). The change in soil properties after bioremediation treatment positively promoted the reduction in the potential mobility of pollutants by the increase in pH, CaCO3 content and organic carbon. Anyway, the bioassay with Lactuca sativa, indicated that around 25% of the soils showed toxicity by the reduction of the root elongation in relation to the control samples. Our results indicate that monitoring of the GGC is still needed, together with the application of soil recovery measures to reduce the potential toxicity in some sectors of the affected area.

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Impacts of Skidding Traffic Intensity on Soil Disturbance, Soil Recovery, and Aspen Regeneration in North Central Minnesota

Northern Journal of Applied Forestry ◽

10.1093/njaf/24.3.177 ◽

2007 ◽

Vol 24 (3) ◽

pp. 177-183 ◽

Cited By ~ 39

Author(s):

Eric K. Zenner ◽

Jeremiah T. Fauskee ◽

Alaina L. Berger ◽

Klaus J. Puettmann

Keyword(s):

Populus Tremuloides ◽

Soil Surface ◽

Soil Disturbance ◽

Quaking Aspen ◽

Partial Recovery ◽

Traffic Intensity ◽

Basal Diameter ◽

Disturbance Gradient ◽

Soil Recovery ◽

Number Of Passes

Abstract We investigated the effects of different levels of ground-based skidding traffic intensity on soil disturbance, characterized by resistance to penetration (RP) within the top 15 cm of soil, as well as soil recovery, regeneration, and early growth of quaking aspen (Populus tremuloides Michx.) suckers 3 years after a clearcut with reserves summer harvest. Equipment traffic was confined to a network of skid trails, and a GPS was used to determine the number of skidder passes at each of 30 sampling points that were preestablished along an anticipated disturbance gradient ranging from landings to skid trails to areas off skid trails. Thirty-one percent of the harvest area was affected by skid traffic, and up to 603 passes were recorded for a plot. RP increased nonlinearly with the number of passes and reached highest levels at the soil surface. Three years after harvest, soils showed partial recovery in the upper 10-cm layer, with full recovery of the surface layer (0–5 cm depth) when affected by 4 or fewer passes. The deepest layer (10–15 cm), however, showed little recovery since harvest. Sucker density, height, and basal diameter of all suckers and height, basal diameter, and dbh of the tallest suckers were significantly reduced with increasing traffic intensity but were not related to increases in RP. Predicted reduction of sucker density was approximately one-third after 10 passes; reductions of height, basal diameter, and dbh were between 1.5 and 2.5% at 10 passes and 3.5 and 6.5% at 25 passes. Because skidding traffic affected only a limited portion of the stand, the productivity of the future aspen stand was not severely impaired, at least in the very short term.

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Soil recovery and reclamation of mined lands

Soils and Landscape Restoration ◽

10.1016/b978-0-12-813193-0.00006-0 ◽

2021 ◽

pp. 161-191

Author(s):

Jan Frouz

Keyword(s):

Soil Recovery

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Evaluating Soil–Root Interaction of Hybrid Larch Seedlings Planted under Soil Compaction and Nitrogen Loading

Forests ◽

10.3390/f11090947 ◽

2020 ◽

Vol 11 (9) ◽

pp. 947

Author(s):

Tetsuto Sugai ◽

Satoko Yokoyama ◽

Yutaka Tamai ◽

Hirotaka Mori ◽

Enrico Marchi ◽

...

Keyword(s):

Root Development ◽

Soil Compaction ◽

Fine Root ◽

Morphological Changes ◽

Nitrogen Loading ◽

Hybrid Larch ◽

Soil Hardness ◽

Hardness Change ◽

N Loading ◽

Soil Recovery

Although compacted soil can be recovered through root development of planted seedlings, the relationship between root morphologies and soil physical properties remain unclear. We investigated the impacts of soil compaction on planted hybrid larch F1 (Larix gmelinii var. japonica×L. kaempferi, hereafter F1) seedlings with/without N loading. We assumed that N loading might increase the fine root proportion of F1 seedlings under soil compaction, resulting in less effects of root development on soil recovery. We established experimental site with different levels of soil compaction and N loading, where two-year-old F1 seedlings were planted. We used a hardness change index (HCI) to quantify a degree of soil hardness change at each depth. We evaluated root morphological responses to soil compaction and N loading, focusing on ectomycorrhizal symbiosis. High soil hardness reduced the total dry mass of F1 seedlings by more than 30%. Significant positive correlations were found between HCI and root proportion, which indicated that F1 seedling could enhance soil recovery via root development. The reduction of fine root density and its proportion due to soil compaction was observed, while these responses were contrasting under N loading. Nevertheless, the relationships between HCI and root proportion were not changed by N loading. The relative abundance of the larch-specific ectomycorrhizal fungi under soil compaction was increased by N loading. We concluded that the root development of F1 seedling accelerates soil recovery, where N loading could induce root morphological changes under soil compaction, resulting in the persistent relationship between root development and soil recovery.

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