Temporal changes in soil organic carbon and aggregate-associated organic carbon after reclamation of abandoned, salinized farmland

SUMMARYA field experiment was conducted to quantify changes in soil aggregation and aggregate-associated soil organic carbon (SOC) concentration 1, 3, 5 and 10 years after abandoned, salinized land in the Manasi River Basin was reclaimed for cotton (Gossypium hirsutum L.). Results showed that reclamation significantly increased SOC concentrations and SOC stocks. Specifically, 10 years of cotton production increased SOC concentrations by 45% in the 0–60 cm depth and SOC stocks by 35%. The SOC concentrations and stocks decreased as soil depth increased. Reclamation time, season and soil depth had significant interaction effects on SOC. The SOC concentrations were significantly and positively correlated with available soil nitrogen and available soil phosphorus. Compared with abandoned farmland, macro-aggregate-associated (>250 µm) SOC concentrations in the 0–60 cm depth increased by 47% after 5 years of cotton production and by 53% after 10 years of cotton production. The contribution of macro-aggregate-associated SOC to total SOC in the 0–60 cm depth increased by 87% after 5 years of cotton production and by 69% after 10 years of cotton production. The findings indicate that soil aggregates were more stable after abandoned, salinized farmland was reclaimed for cotton production. Furthermore, cotton production can increase SOC concentrations and sequester C in this arid area.

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Soil Organic Carbon Depletion from Forests to Grasslands Conversion in Mexico: A Review

Agriculture ◽

10.3390/agriculture8110181 ◽

2018 ◽

Vol 8 (11) ◽

pp. 181 ◽

Cited By ~ 6

Author(s):

Deb Aryal ◽

Danilo Morales Ruiz ◽

César Tondopó Marroquín ◽

René Pinto Ruiz ◽

Francisco Guevara Hernández ◽

...

Keyword(s):

Land Use ◽

Organic Carbon ◽

Land Use Change ◽

Soil Organic Carbon ◽

Tropical Forests ◽

Soil Depth ◽

Carbon Stocks ◽

Soil Horizon ◽

Native Forests ◽

Soc Stocks

Land use change from forests to grazing lands is one of the important sources of greenhouse gas emissions in many parts of the tropics. The objective of this study was to analyze the extent of soil organic carbon (SOC) loss from the conversion of native forests to pasturelands in Mexico. We analyzed 66 sets of published research data with simultaneous measurements of soil organic carbon stocks between native forests and pasturelands in Mexico. We used a generalized linear mixed effect model to evaluate the effect of land use change (forest versus pasture), soil depth, and original native forest types. The model showed that there was a significant reduction in SOC stocks due to the conversion of native forests to pasturelands. The median loss of SOC ranged from 31.6% to 52.0% depending upon the soil depth. The highest loss was observed in tropical mangrove forests followed by highland tropical forests and humid tropical forests. Higher loss was detected in upper soil horizon (0–30 cm) compared to deeper horizons. The emissions of CO2 from SOC loss ranged from 46.7 to 165.5 Mg CO2 eq. ha−1 depending upon the type of original native forests. In this paper, we also discuss the effect that agroforestry practices such as silvopastoral arrangements and other management practices like rotational grazing, soil erosion control, and soil nutrient management can have in enhancing SOC stocks in tropical grasslands. The results on the degree of carbon loss can have strong implications in adopting appropriate management decisions that recover or retain carbon stocks in biomass and soils of tropical livestock production systems.

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Impacts of fire on soil organic carbon stocks in a grazed semi-arid tropical Australian savanna: accounting for landscape variability

The Rangeland Journal ◽

10.1071/rj14044 ◽

2014 ◽

Vol 36 (4) ◽

pp. 359 ◽

Cited By ~ 7

Author(s):

D. E. Allen ◽

P. M. Bloesch ◽

R. A. Cowley ◽

T. G. Orton ◽

J. E. Payne ◽

...

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Spatial Variability ◽

Management Practices ◽

Soil Depth ◽

Carbon Stocks ◽

Soil Organic Carbon Stocks ◽

Semi Arid ◽

Soc Stocks

Fire and grazing are commonplace in Australian tropical savannas and the effects of these management practices on soil organic carbon stocks (SOC) is not well understood. A long-term (20 years) experiment studying the effects of fire on a grazed semi-arid tropical savanna was used to increase this understanding. Treatments, including frequency of fire (every 2, 4 and 6 years), season of fire [early (June) vs late (October) dry season] and unburnt control plots, were imposed on Vertosol grassland and Calcarosol woodland sites, which were grazed. Additionally long-term enclosures [unburnt (except the Calcarosol in 2001) and ungrazed since 1973] on each soil type adjacent to each site were sampled, although not included in statistical analyses. SOC stocks were measured to a soil depth of 0.3 m using a wet oxidation method (to avoid interference by carbonates) and compared on an equivalent soil mass basis. Significant treatment differences in SOC stocks were tested for, while accounting for spatial background variation within each site. SOC stocks (0–0.3 m soil depth) ranged between 10.1 and 28.9 t ha–1 (Vertosol site) and 20.7 and 54.9 t ha–1 (Calcarosol site). There were no consistent effects of frequency or season of fire on SOC stocks, possibly reflecting the limited statistical power of the study and inherent spatial variability observed. Differences in the response to frequency and season of fire observed between these soils may have been due to differences in clay type, plant species composition and/or preferential grazing activity associated with fire management. There may also have been differences in C input between treatments and sites due to differences in the herbage mass and post-fire grazing activity on both sites and changed pasture composition, higher herbage fuel load, and a reduction in woody cover on the Vertosol site. This study demonstrated the importance of accounting for background spatial variability and treatment replication (in the absence of baseline values) when assessing SOC stocks in relation to management practices. Given the absence of baseline SOC values and the potentially long period required to obtain changes in SOC in rangelands, modelling of turnover of SOC in relation to background spatial variability would enable management scenarios to be considered in relation to landscape variation that may be unrelated to management. These considerations are important for reducing uncertainty in C-flux accounting and to provide accurate and cost-effective methods for land managers considering participation in the C economy.

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Isotope Analysis Reveals Differential Impacts of Artificial and Natural Afforestation On Soil Organic Carbon Dynamics in Abandoned Farmland

10.21203/rs.3.rs-238894/v2 ◽

2021 ◽

Author(s):

Dongrui Di ◽

Guangwei Huang

Keyword(s):

Land Use ◽

Organic Carbon ◽

Soil Organic Carbon ◽

Soil Aggregates ◽

Aggregate Size ◽

Plant Residues ◽

Significant Difference ◽

Land Use System ◽

Time Substitution ◽

Soc Stocks

Abstract Backgrounds A multitude of studies have applied different methods to study the dynamics of soil organic carbon (SOC), but the differential impact of artificial and natural afforestation on SOC dynamic are still poorly understood. Methods and aims We investigated the SOC dynamics following artificial and natural afforestation in Loess Plateau of China, characterizing soil structure and stoichiometry using stable isotope carbon and radiocarbon models. We aim to compare SOC dynamics, clarify SOC source under different afforestation, examine comparability of the study areas and find how soil aggregate size classes control SOC dynamics, finally to evaluate effect of reforestation project.Results The 0-10cm and 10-20 cm SOC stocks were significant higher than other two land-use system. At other depths, there is no significant difference among the three land-use system. Total top soil SOC stocks, C:N and C:P of differently sized soil aggregates significantly increased following afforestation. 13C results and Radiocarbon models indicated that the SOC decomposition rate and new SOC input rate were lower under natural afforestation than artificial afforestation. Conclusions Afforestation can accumulate SOC in top soils mainly resulting from in topsoil changing. SOC resource is mainly from macroaggregate formation provided by fresh plant residues. SOC loss from soil respiration was derived from microaggregates during afforestation. The“space-for-time substitution” method is suitable for comparability of the study areas.

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Revegetation pattern affecting accumulation of organic carbon and total nitrogen in reclaimed mine soils

10.7287/peerj.preprints.27936 ◽

2019 ◽

Author(s):

Ping P Zhang ◽

Yan L Zhang ◽

Jun C Jia ◽

Yong X Cui ◽

Xia Wang ◽

...

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Loess Plateau ◽

Total Nitrogen ◽

Land Reclamation ◽

Arid Area ◽

Mine Soils ◽

The Loess Plateau ◽

Mine Sites ◽

Soc Stocks

Selecting optimal revegetation patterns, i.e., patterns that are more effective for soil organic carbon (SOC) and total nitrogen (TN) accumulation is particularly important for mine land reclamation. However, there have been few evaluations of the effects of different revegetation patterns on the SOC and TN in reclaimed mine soils on the Loess Plateau, China. In this study, the SOC and TN stocks were investigated at reclaimed mine sites (RMSs), including artificially revegetated sites (ARSs) (arbors [Ar], bushes [Bu], arbor-bush mixtures [AB], and grasslands [Gr]) and a natural recovery site (NRS), as well as at undisturbed native sites (UNSs). Overall, the SOC and TN stocks in the RMSs were lower than those in the UNSs over 10–13 years after reclamation. Except for those in Ar, the SOC and TN stocks in the ARSs were significantly larger than those in the NRS. Compared with those in the NRS, the total SOC stocks in the 100 cm soil interval increased by 51.4%, 59.9%, and 109.9% for Bu, AB, and Gr, respectively, and the TN stocks increased by 33.1%, 35.1%, and 57.9%. The SOC stocks in the 0 – 100 cm soil interval decreased in the order of Gr (3.78 kg m –2) > AB (2.88 kg m–2) ≥ Bu (2.72 kg m–2), and the TN stocks exhibited a similar trend. These results suggest that grasslands were more favorable than woodlands for SOC and TN accumulation in this arid area, especially in Ar. Thus, in terms of the accumulation of SOC and TN, grassland planting is recommended as a revegetation pattern for areas with reclaimed mine soils.

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Stocks and Stoichiometry of Soil Organic Carbon, Total Nitrogen, and Total Phosphorus after Vegetation Restoration in the Loess Hilly Region, China

Forests ◽

10.3390/f10010027 ◽

2019 ◽

Vol 10 (1) ◽

pp. 27 ◽

Cited By ~ 12

Author(s):

Hongwei Xu ◽

Qing Qu ◽

Peng Li ◽

Ziqi Guo ◽

Entemake Wulan ◽

...

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Total Nitrogen ◽

Total Phosphorus ◽

Soil Depth ◽

Vegetation Restoration ◽

N:P Ratios ◽

Hilly Region ◽

Restoration Age ◽

Soc Stocks

The Loess Plateau is an important region for vegetation restoration in China; however, changes in soil organic carbon (SOC), soil nutrients, and stoichiometry after restoration in this vulnerable ecoregion are not well understood. Typical restoration types, including orchardland, grassland, shrubland, and forestland, were chosen to examine changes in the stocks and stoichiometry of SOC, soil total nitrogen (TN), and soil total phosphorus (TP) at different soil depths and recovery times. Results showed that SOC stocks first increased and then stabilized in orchardland, grassland, and shrubland at 0–30 cm depths, while in forestland, SOC stocks gradually increased. Soil TN stocks first increased and then decreased in orchardland, shrubland, and forestland with restoration age at 0–30 cm depths, while soil TP stocks showed little variation between restoration types; at the same time, the overall C:N, C:P, and N:P ratios increased with restoration age. In the later stages of restoration, the stocks of SOC and soil TN at 0–30 cm soil depths were still lower than those in natural grassland and natural forest. Additionally, the SOC, soil TN, and soil TP stocks and the C:N, C:P, and N:P ratios decreased with soil depth. The forestland had the highest rate of change in SOC and soil TN stocks, at 0–10 cm soil depth. These results indicate a complex response of SOC, soil TN, and soil TP stocks and stoichiometry to vegetation restoration, which could have important implications for understanding C, N, and P changes and nutrient limitations after vegetation restoration.

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Revegetation pattern affecting accumulation of organic carbon and total nitrogen in reclaimed mine soils

PeerJ ◽

10.7717/peerj.8563 ◽

2020 ◽

Vol 8 ◽

pp. e8563

Author(s):

Ping Ping Zhang ◽

Yan Le Zhang ◽

Jun Chao Jia ◽

Yong Xing Cui ◽

Xia Wang ◽

...

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Loess Plateau ◽

Total Nitrogen ◽

Land Reclamation ◽

Arid Area ◽

Mine Soils ◽

The Loess Plateau ◽

Mine Sites ◽

Soc Stocks

Selecting optimal revegetation patterns, i.e., patterns that are more effective for soil organic carbon (SOC) and total nitrogen (TN) accumulation, is particularly important for mine land reclamation. However, there have been few evaluations of the effects of different revegetation patterns on the SOC and TN in reclaimed mine soils on the Loess Plateau, China. In this study, the SOC and TN stocks were investigated at reclaimed mine sites (RMSs), including artificially revegetated sites (ARSs) (arbors (Ar), bushes (Bu), arbor-bush mixtures (AB), and grasslands (Gr)) and a natural recovery site (NRS), as well as at undisturbed native sites (UNSs). Overall, the SOC and TN stocks in the RMSs were lower than those in the UNSs over 10–13 years after reclamation. The SOC stocks in the RMSs and UNSs only differed in the top 0–20 cm of the soil (p < 0.05). Except for those in Ar, the SOC and TN stocks in the ARSs were significantly larger than those in the NRS (p < 0.05). Compared with those in the NRS, the total SOC stocks in the 100 cm soil interval increased by 51.4%, 59.9%, and 109.9% for Bu, AB, and Gr, respectively, and the TN stocks increased by 33.1%, 35.1%, and 57.9%. The SOC stocks in the 0–100 cm soil interval decreased in the order of Gr (3.78 kg m−2) > AB (2.88 kg m−2) ≥ Bu (2.72 kg m−2), and the TN stocks exhibited a similar trend. These results suggest that grasslands were more favorable than woodlands for SOC and TN accumulation in this arid area. Thus, in terms of the accumulation of SOC and TN, grassland planting is recommended as a revegetation pattern for areas with reclaimed mine soils.

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Revegetation pattern affecting accumulation of organic carbon and total nitrogen in reclaimed mine soils

10.7287/peerj.preprints.27936v1 ◽

2019 ◽

Author(s):

Ping P Zhang ◽

Yan L Zhang ◽

Jun C Jia ◽

Yong X Cui ◽

Xia Wang ◽

...

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Loess Plateau ◽

Total Nitrogen ◽

Land Reclamation ◽

Arid Area ◽

Mine Soils ◽

The Loess Plateau ◽

Mine Sites ◽

Soc Stocks

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Dynamics of Soil Organic Carbon and Labile Carbon Fractions in Soil Aggregates Affected by Different Tillage Managements

Sustainability ◽

10.3390/su13031541 ◽

2021 ◽

Vol 13 (3) ◽

pp. 1541

Author(s):

Xiaolin Shen ◽

Lili Wang ◽

Qichen Yang ◽

Weiming Xiu ◽

Gang Li ◽

...

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Soil Aggregates ◽

Aggregate Stability ◽

Soil Aggregate ◽

No Tillage ◽

Labile Carbon ◽

Carbon Fractions ◽

Soil Aggregate Stability ◽

Positive Effects

Our study aimed to provide a scientific basis for an appropriate tillage management of wheat-maize rotation system, which is beneficial to the sustainable development of agriculture in the fluvo-aquic soil areas in China. Four tillage treatments were investigated after maize harvest, including rotary tillage with straw returning (RT), deep ploughing with straw returning (DP), subsoiling with straw returning (SS), and no tillage with straw mulching (NT). We evaluated soil organic carbon (SOC), dissolved organic carbon (DOC), permanganate oxidizable carbon (POXC), microbial biomass carbon (MBC), and particulate organic carbon (POC) in bulk soil and soil aggregates with five particle sizes (>5 mm, 5–2 mm, 2–1 mm, 1–0.25 mm, and <0.25 mm) under different tillage managements. Results showed that compared with RT treatment, NT treatment not only increased soil aggregate stability, but also enhanced SOC, DOC, and POC contents, especially those in large size macroaggregates. DP treatment also showed positive effects on soil aggregate stability and labile carbon fractions (DOC and POXC). Consequently, we suggest that no tillage or deep ploughing, rather than rotary tillage, could be better tillage management considering carbon storage. Meanwhile, we implied that mass fractal dimension (Dm) and POXC could be effective indicators of soil quality, as affected by tillage managements.

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Spatial heterogeneity and environmental predictors of permafrost region soil organic carbon stocks

Science Advances ◽

10.1126/sciadv.aaz5236 ◽

2021 ◽

Vol 7 (9) ◽

pp. eaaz5236 ◽

Cited By ~ 1

Author(s):

Umakant Mishra ◽

Gustaf Hugelius ◽

Eitan Shelef ◽

Yuanhe Yang ◽

Jens Strauss ◽

...

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Spatial Heterogeneity ◽

Surface Air Temperature ◽

Spatially Explicit ◽

Soil Profiles ◽

Permafrost Region ◽

Environmental Predictors ◽

Soil Organic Carbon Stocks ◽

Soc Stocks

Large stocks of soil organic carbon (SOC) have accumulated in the Northern Hemisphere permafrost region, but their current amounts and future fate remain uncertain. By analyzing dataset combining >2700 soil profiles with environmental variables in a geospatial framework, we generated spatially explicit estimates of permafrost-region SOC stocks, quantified spatial heterogeneity, and identified key environmental predictors. We estimated that 1014−175+194 Pg C are stored in the top 3 m of permafrost region soils. The greatest uncertainties occurred in circumpolar toe-slope positions and in flat areas of the Tibetan region. We found that soil wetness index and elevation are the dominant topographic controllers and surface air temperature (circumpolar region) and precipitation (Tibetan region) are significant climatic controllers of SOC stocks. Our results provide first high-resolution geospatial assessment of permafrost region SOC stocks and their relationships with environmental factors, which are crucial for modeling the response of permafrost affected soils to changing climate.

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