scholarly journals Drivers of Organic Carbon Stocks in Different LULC History and Along Soil Depth for a 30 Years Image Time Series

2021 ◽  
Vol 13 (11) ◽  
pp. 2223
Author(s):  
Mahboobeh Tayebi ◽  
Jorge Tadeu Fim Rosas ◽  
Wanderson de Sousa Mendes ◽  
Raul Roberto Poppiel ◽  
Yaser Ostovari ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Land Use ◽  
Random Forest ◽  
Organic Carbon ◽  
Soil Properties ◽  
Soil Depth ◽  
Controlling Factors ◽  
Land Use History ◽  
The Impact ◽  
Soc Stocks

Soil organic carbon (SOC) stocks are a remarkable property for soil and environmental monitoring. The understanding of their dynamics in crop soils must go forward. The objective of this study was to determine the impact of temporal environmental controlling factors obtained by satellite images over the SOC stocks along soil depth, using machine learning algorithms. The work was carried out in São Paulo state (Brazil) in an area of 2577 km2. We obtained a dataset of boreholes with soil analyses from topsoil to subsoil (0–100 cm). Additionally, remote sensing covariates (30 years of land use history, vegetation indexes), soil properties (i.e., clay, sand, mineralogy), soil types (classification), geology, climate and relief information were used. All covariates were confronted with SOC stocks contents, to identify their impact. Afterwards, the abilities of the predictive models were tested by splitting soil samples into two random groups (70 for training and 30% for model testing). We observed that the mean values of SOC stocks decreased by increasing the depth in all land use and land cover (LULC) historical classes. The results indicated that the random forest with recursive features elimination (RFE) was an accurate technique for predicting SOC stocks and finding controlling factors. We also found that the soil properties (especially clay and CEC), terrain attributes, geology, bioclimatic parameters and land use history were the most critical factors in controlling the SOC stocks in all LULC history and soil depths. We concluded that random forest coupled with RFE could be a functional approach to detect, map and monitor SOC stocks using environmental and remote sensing data.

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

Agriculture ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 181 ◽  
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.

Deriving regional pedotransfer functions to estimate soil bulk density in Austria

2020 ◽  
Vol 71 (4) ◽  
pp. 241-252
Author(s):  
Cecilie Foldal ◽  
Robert Jandl ◽  
Andreas Bohner ◽  
Ambros Berger
Keyword(s):  
Land Use ◽  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Bulk Density ◽  
Linear Models ◽  
Soil Depth ◽  
Soil Bulk Density ◽  
Pedotransfer Functions ◽  
Undisturbed Soil ◽  
The Impact

Summary Soil bulk density is a required variable for quantifying stocks of elements in soils and is therefore instrumental for the evaluation of land-use related climate change mitigation measures. Our motivation was to derive a set of pedotransfer functions for soil bulk densities usable to accommodate different levels of data availabilities. We derived sets of linear equations for bulk density that are appropriate for different forms of land-use. After introducing uncertainty factors for measured parameters, we ran the linear models repeatedly in a Monte Carlo simulation in order to test the impact of inaccuracy. The reliability of the models was evaluated by a cross-validation. The single best predictor of soil bulk density is the content of soil organic carbon, yielding estimates with an adjusted R2 of approximately 0.5. A slight improvement of the estimate is possible when additionally, soil texture and soil depth are known. Residual analysis advocated the derivation of land-use specific models. Using transformed variables and assessing land-use specific pedotransfer functions, the determination coefficient (adjusted R2) of the multiple linear models ranged from 0.43 in cropland up to 0.65 for grassland soils. Compared to pedotransfer function, from the literature, the performance of the linear modes were similar but more accurate. Taking into account the likely inaccuracies when measuring soil organic carbon, the soil bulk density can be estimated with an accuracy of +/− 9 to 25% depending on land-use. We recommend measuring soil bulk density by standardized sampling of undisturbed soil cores, followed by post-processing of the samples in the lab by internationally harmonized protocols. Our pedotransfer functions are accurately and transparently presented, and derived from well-documented and high-quality soil data sets. We therefore consider them particularly useful in Austria, where the measured values for soil bulk densities are not available.

scholarly journals Effects of Different Land Use Types Managed By Smallholder Farmers on Soil Properties in Central Ethiopia

2021 ◽  
Author(s):  
Getahun Haile ◽  
Mulugeta Lemenih ◽  
Fisseha Itanna ◽  
Beyene Teklu ◽  
Getachew Agegnehu
Keyword(s):  
Land Use ◽  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Soil Properties ◽  
Total Nitrogen ◽  
Soil Depth ◽  
Chemical Properties ◽  
Grazing Land ◽  
Land Use Types ◽  
And Chemical Properties

Abstract Background Aim: Land use change causes a remarkable change in soil properties. The nature of change depends on multiple factors such as soil type, type and intensity of land use, climate, and the like. This study investigated the variation in soil physicochemical properties across five common land use practices i.e., enset system, farmland, and grazing-land (closed and open), and Eucalyptus woodlots practiced on originally same soil type and comparable topographic and climatic settings.Methods: A total of 105 disturbed and undisturbed soil samples [5 treatments (land use types) *7 replications (household)* 3 soil depth layers: 0–15cm, 15–30 cm, 30–45cm] were collected for selected soil chemical and physical analyses. Standard soil analytical procedures were followed in carrying out soil analysis. To meet the assumptions of normal distribution and homogeneity of variances, soil data on available phosphors were log-transformed before statistical analysis was undertaken and reported after back transformation. Two way analysis of variable were used to investigate the effects of land use and soil depth and their interaction on soil properties and when the analysis showed a significant difference (p <0.05) among land use and soil depth men separation were made using Turkey’s pairwise comparisons.Results: There were significant differences in physical and chemical properties of soil across land use and soil depth categories. Enset system had significantly higher pH, available phosphorus (P), exchangeable potassium (K+), soil organic carbon (SOC), and total nitrogen (TN) and their stocks than other land use types. Enset fields had higher SOC (78.4%) and soil TN (75%), and SOC and TN stocks of (66%) and (58%), respectively than cereal farmland. This study had also revealed a less expected finding of higher soil organic carbon and total nitrogen under Eucalyptus wood than farm land. Soil carbon and total nitrogen stocks showed a decreasing trend of enset system> closed grazing-land > eucalyptus woodlot > open grazing-land > farmland 0-45cm.Conclusion: Overall, some land use systems (e. g. enset agroforestry) improve the soil biophysical and chemical properties, while others such as cereal production degrade the soil. Hence appropriate land and soil management intervention should be promptly adapted to mitigating the continuous loss of nutrient from the dominantly practiced cereal farm land through maintaining crop residues, manure, crop rotation and scaling up agro-forestry system.

scholarly journals METHODOLOGICAL PROPOSAL FOR THE IDENTIFICATION OF MARGINAL LANDS WITH REMOTE SENSING-DERIVED PRODUCTS AND ANCILLARY DATA

2021 ◽  
Author(s):  
Jesús Torralba ◽  
Luis Á. Ruiz ◽  
Charalampos Georgiadis ◽  
Petros Patias ◽  
Rodrigo Gómez-Conejo ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Land Use ◽  
Land Cover ◽  
Soil Properties ◽  
Soil Texture ◽  
Soil Depth ◽  
Google Earth ◽  
Marginal Land ◽  
Ancillary Data ◽  
Marginal Lands

The concept of marginal land (ML) is dynamic and depends on various factors related to the environment, climate, scale,culture, and economic sector. The current methods for identifying ML are diverse, they employ multiple parameters andvariables derived from land use and land cover, and mostly reflect specific management purposes. A methodologicalapproach for the identification of marginal lands using remote sensing and ancillary data products and validated on samplesfrom four European countries (i.e., Germany, Spain, Greece, and Poland) is presented in this paper. The methodologyproposed combines land use and land cover data sets as excluding indicators (forest, croplands, protected areas,impervious areas, land-use change, water bodies, and permanent snow areas) and environmental constraints informationas marginality indicators: (i) physical soil properties, in terms of slope gradient, erosion, soil depth, soil texture, percentageof coarse soil texture fragments, etc.; (ii) climatic factors e.g. aridity index; (iii) chemical soil properties, including soil pH,cation exchange capacity, contaminants, and toxicity, among others. This provides a common vision of marginality thatintegrates a multidisciplinary approach. To determine the ML, we first analyzed the excluding indicators used to delimit theareas with defined land use. Then, thresholds were determined for each marginality indicator through which the landproductivity progressively decreases. Finally, the marginality indicator layers were combined in Google Earth Engine. Theresult was categorized into 3 levels of productivity of ML: high productivity, low productivity, and potentially unsuitable land.The results obtained indicate that the percentage of marginal land per country is 11.64% in Germany, 19.96% in Spain,18.76% in Greece, and 7.18% in Poland. The overall accuracies obtained per country were 60.61% for Germany, 88.87%for Spain, 71.52% for Greece, and 90.97% for Poland.

scholarly journals Spatial variability in soil organic carbon in a tropical montane landscape: associations between soil organic carbon and land use, soil properties, vegetation, and topography vary across plot to landscape scales

SOIL ◽  
2017 ◽  
Vol 3 (3) ◽  
pp. 123-137 ◽  
Author(s):  
Marleen de Blécourt ◽  
Marife D. Corre ◽  
Ekananda Paudel ◽  
Rhett D. Harrison ◽  
Rainer Brumme ◽  
...  
Keyword(s):  
Land Use ◽  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Soil Properties ◽  
Spatial Scales ◽  
Carbon Stocks ◽  
Land Use Types ◽  
Tea Plantations ◽  
Open Land ◽  
Soc Stocks

Abstract. Presently, the lack of data on soil organic carbon (SOC) stocks in relation to land-use types and biophysical characteristics prevents reliable estimates of ecosystem carbon stocks in montane landscapes of mainland SE Asia. Our study, conducted in a 10 000 ha landscape in Xishuangbanna, SW China, aimed at assessing the spatial variability in SOC concentrations and stocks, as well as the relationships of SOC with land-use types, soil properties, vegetation characteristics and topographical attributes at three spatial scales: (1) land-use types within a landscape (10 000 ha), (2) sampling plots (1 ha) nested within land-use types (plot distances ranging between 0.5 and 12 km), and (3) subplots (10 m radius) nested within sampling plots. We sampled 27 one-hectare plots – 10 plots in mature forests, 11 plots in regenerating or highly disturbed forests, and 6 plots in open land including tea plantations and grasslands. We used a sampling design with a hierarchical structure. The landscape was first classified according to land-use types. Within each land-use type, sampling plots were randomly selected, and within each plot we sampled within nine subplots. SOC concentrations and stocks did not differ significantly across the four land-use types. However, within the open-land category, SOC concentrations and stocks in grasslands were higher than in tea plantations (P < 0.01 for 0–0.15 m, P = 0.05 for 0.15–0.30 m, P = 0.06 for 0–0.9 m depth). The SOC stocks to a depth of 0.9 m were 177.6 ± 19.6 (SE) Mg C ha−1 in tea plantations, 199.5 ± 14.8 Mg C ha−1 in regenerating or highly disturbed forests, 228.6 ± 19.7 Mg C ha−1 in mature forests, and 236.2 ± 13.7 Mg C ha−1 in grasslands. In this montane landscape, variability within plots accounted for more than 50 % of the overall variance in SOC stocks to a depth of 0.9 m and the topsoil SOC concentrations. The relationships of SOC concentrations and stocks with land-use types, soil properties, vegetation characteristics, and topographical attributes varied across spatial scales. Variability in SOC within plots was determined by litter layer carbon stocks (P < 0.01 for 0–0.15 m and P = 0.03 for 0.15–0.30 and 0–0.9 m depth) and slope (P ≤ 0.01 for 0–0.15, 0.15–0.30, and 0–0.9 m depth) in open land, and by litter layer carbon stocks (P < 0.001 for 0–0.15, 0.15–0.30 and 0–0.9 m depth) and tree basal area (P < 0.001 for 0–0.15 m and P = 0.01 for 0–0.9 m depth) in forests. Variability in SOC among plots in open land was related to the differences in SOC concentrations and stocks between grasslands and tea plantations. In forests, the variability in SOC among plots was associated with elevation (P < 0.01 for 0–0.15 m and P = 0.09 for 0–0.9 m depth). The scale-dependent relationships between SOC and its controlling factors demonstrate that studies that aim to investigate the land-use effects on SOC need an appropriate sampling design reflecting the controlling factors of SOC so that land-use effects will not be masked by the variability between and within sampling plots.

scholarly journals Effects of Land Use Change on the Soil Organic Carbon and Selected Soil Properties in the Sultan Marshes, Turkey

2021 ◽  
Author(s):  
Selma Yaşar Korkanç ◽  
Mustafa Korkanç ◽  
Muhammet Hüseyin Mert ◽  
Abdurrahman Geçili ◽  
Yusuf Serengil
Keyword(s):  
Land Use ◽  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Soil Properties ◽  
Bulk Density ◽  
Carbon Stock ◽  
Soil Depth ◽  
Aggregate Stability ◽  
Carbon Stocks ◽  
Effects Of Land Use

Abstract This study aims the effects of land use changes on the carbon storage capacity and some soil properties of The Sultan Marshes was partially drained during the middle of the last century and converted to other land uses. Undisturbed soil sampling was performed in different land use types (rangelands, shrubs, marsh, agriculture, and dried lake area) in the wetland area at depths of 0-50 cm, and soil organic carbon (SOC), bulk density, and carbon stocks of soils for each land use type were calculated at 10 cm soil depth levels. Furthermore, disturbed soil samples were taken at two soil depths (0-20 cm and 20-40 cm), and the particle size distribution, pH, electrical conductivity (EC), aggregate stability and dispersion ratio (DR) properties of the soils were analyzed. Data were processed using ANOVA, Duncan’s test, and Pearson’s correlation analysis. The soil properties affected by land use change were SOC, carbon stock, pH, EC, aggregate stability, clay, silt, sand contents, and bulk density. SOC and carbon stocks were high in rangeland, marsh, and shrub land, while they were low in agriculture and drained lake areas. As the soil depth increased, SOC and carbon stock decreased. The organic carbon content of the soils exhibited positive relationships with aggregate stability, clay, and carbon stock, while it showed a negative correlation with bulk density, pH, and DR. The results showed that the drainage and conversion of the wetland caused a significant decrease in the carbon contents of the soils.

scholarly journals Global distribution of soil organic carbon – Part 2: Certainty of changes related to land use and climate

SOIL ◽  
2015 ◽  
Vol 1 (1) ◽  
pp. 367-380 ◽  
Author(s):  
M. Köchy ◽  
A. Don ◽  
M. K. van der Molen ◽  
A. Freibauer
Keyword(s):  
Land Use ◽  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Net Primary Productivity ◽  
Water Saturation ◽  
Controlling Factors ◽  
Soil C ◽  
Climate Effects ◽  
Global Soil ◽  
Soc Stocks

Abstract. Global biosphere models vary greatly in their projections of future changes of global soil organic carbon (SOC) stocks and aggregated global SOC masses in response to climate change. We estimated the certainty (likelihood) and quantity of increases and decreases on a half-degree grid. We assessed the effect of changes in controlling factors, including net primary productivity (NPP), litter quality, soil acidity, water saturation, depth of permafrost, land use, temperature, and aridity associated with probabilities (Bayesian network) on an embedded, temporally discrete, three-pool decomposition model. In principle, controlling factors were discretized into classes, where each class was associated with a probability and linked to an output variable. This creates a network of links that are ultimately linked to a set of equations for carbon (C) input and output to and from soil C pools. The probability-weighted results show that, globally, climate effects on NPP had the strongest impact on SOC stocks and the certainty of change after 75 years. Actual land use had the greatest effect locally because the assumed certainty of land use change per unit area was small. The probability-weighted contribution of climate to decomposition was greatest in the humid tropics because of greater absolute effects on decomposition fractions at higher temperatures. In contrast, climate effects on decomposition fractions were small in cold regions. Differences in decomposition rates between contemporary and future climate were greatest in arid subtropical regions because of projected strong increases in precipitation. Warming in boreal and arctic regions increased NPP, balancing or outweighing potential losses from thawing of permafrost. Across contrasting NPP scenarios, tropical mountain forests were identified as hotspots of future highly certain C losses. Global soil C mass will increase by 1% with a certainty of 75% if NPP increases due to carbon dioxide fertilization. At a certainty level of 75%, soil C mass will not change if CO2-induced increase of NPP is limited by nutrients.

Land use effects on the geochemical soil properties and their control on organic carbon in volcanic soils, near Bandung area (Indonesia)

2020 ◽  
Author(s):  
Sastrika Anindita ◽  
Peter Finke ◽  
Steven Sleutel
Keyword(s):  
Land Use ◽  
Organic Carbon ◽  
Soil Properties ◽  
Agricultural Land ◽  
Pine Forest ◽  
Land Uses ◽  
Volcanic Soils ◽  
Cultivation Period ◽  
Weathering Degree ◽  
The Impact

&lt;p&gt;Land use change can significantly influence both mineralogy and chemical soil properties. This conversion, particularly from forest to agricultural system occurs often in volcanic soils due to their favorable properties for food production. Under agriculture, minerals can weather faster than in natural vegetation and this also impacts soil functioning. We aim to assess the impact of land use on geochemical soil properties and soil organic carbon across soils of different age. This study was conducted in Mt. Tangkuban Perahu and Mt. Burangrang where the soils were derived from similar andesitic parent material and have different ages based on their lithology. Five sites were selected representing land uses that have been converted (pine forest and agricultural land) and one site of natural forest as the origin of land use. The results showed that land use management enhances the mineral transformation. Pine forest and agricultural sites displayed higher weathering degree than natural forests as indicated by higher clay content, iron crystallinity index and the presence of gibbsite. The weathering degree of soils in agricultural sites might result from the length of cultivation period and soil age. Land use conversion also altered chemical properties such as pH, CEC, basic cations, and the proportion of amorphous materials. Non-crystalline Al and Fe minerals as indicated by Al&lt;sub&gt;o&lt;/sub&gt;+1/2Fe&lt;sub&gt;o&lt;/sub&gt; were highly correlated with organic carbon and specific surface area (SSA) in the subsoils of all land uses. However, we did not see the accumulation of organic carbon in subsoils compared to topsoils as the amount of non-crystalline Al and Fe minerals increases with depth, especially in agricultural lands where the organic fertilizer input is very high. In addition, a significant proportion of carbon was stored in sand aggregate fractions in agricultural land which have longer cultivation period, while it was more readily found in silt and clay fractions in the site with shorter period.&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;

scholarly journals From the Ground Up: Prairies on Reclaimed Mine Land—Impacts on Soil and Vegetation

Land ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 455
Author(s):  
Rebecca M. Swab ◽  
Nicola Lorenz ◽  
Nathan R. Lee ◽  
Steven W. Culman ◽  
Richard P. Dick
Keyword(s):  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Soil Properties ◽  
Plant Community ◽  
Prairie Restoration ◽  
Native Plant ◽  
Soil Microbial ◽  
Prairie Restorations ◽  
Mine Lands ◽  
The Impact

After strip mining, soils typically suffer from compaction, low nutrient availability, loss of soil organic carbon, and a compromised soil microbial community. Prairie restorations can improve ecosystem services on former agricultural lands, but prairie restorations on mine lands are relatively under-studied. This study investigated the impact of prairie restoration on mine lands, focusing on the plant community and soil properties. In southeast Ohio, 305 ha within a ~2000 ha area of former mine land was converted to native prairie through herbicide and planting between 1999–2016. Soil and vegetation sampling occurred from 2016–2018. Plant community composition shifted with prairie age, with highest native cover in the oldest prairie areas. Prairie plants were more abundant in older prairies. The oldest prairies had significantly more soil fungal biomass and higher soil microbial biomass. However, many soil properties (e.g., soil nutrients, β-glucosoidase activity, and soil organic carbon), as well as plant species diversity and richness trended higher in prairies, but were not significantly different from baseline cool-season grasslands. Overall, restoration with prairie plant communities slowly shifted soil properties, but mining disturbance was still the most significant driver in controlling soil properties. Prairie restoration on reclaimed mine land was effective in establishing a native plant community, with the associated ecosystem benefits.

scholarly journals Dynamics of soil organic carbon in the steppes of Russia and Kazakhstan under past and future climate and land use

2021 ◽  
Vol 21 (3) ◽  
Author(s):  
Susanne Rolinski ◽  
Alexander V. Prishchepov ◽  
Georg Guggenberger ◽  
Norbert Bischoff ◽  
Irina Kurganova ◽  
...  
Keyword(s):  
Climate Change ◽  
Land Use ◽  
Organic Carbon ◽  
Land Use Change ◽  
Soil Organic Carbon ◽  
Arable Land ◽  
Future Climate ◽  
Future Climate Change ◽  
Climate Scenarios ◽  
The Impact

AbstractChanges in land use and climate are the main drivers of change in soil organic matter contents. We investigated the impact of the largest policy-induced land conversion to arable land, the Virgin Lands Campaign (VLC), from 1954 to 1963, of the massive cropland abandonment after 1990 and of climate change on soil organic carbon (SOC) stocks in steppes of Russia and Kazakhstan. We simulated carbon budgets from the pre-VLC period (1900) until 2100 using a dynamic vegetation model to assess the impacts of observed land-use change as well as future climate and land-use change scenarios. The simulations suggest for the entire VLC region (266 million hectares) that the historic cropland expansion resulted in emissions of 1.6⋅ 1015 g (= 1.6 Pg) carbon between 1950 and 1965 compared to 0.6 Pg in a scenario without the expansion. From 1990 to 2100, climate change alone is projected to cause emissions of about 1.8 (± 1.1) Pg carbon. Hypothetical recultivation of the cropland that has been abandoned after the fall of the Soviet Union until 2050 may cause emissions of 3.5 (± 0.9) Pg carbon until 2100, whereas the abandonment of all cropland until 2050 would lead to sequestration of 1.8 (± 1.2) Pg carbon. For the climate scenarios based on SRES (Special Report on Emission Scenarios) emission pathways, SOC declined only moderately for constant land use but substantially with further cropland expansion. The variation of SOC in response to the climate scenarios was smaller than that in response to the land-use scenarios. This suggests that the effects of land-use change on SOC dynamics may become as relevant as those of future climate change in the Eurasian steppes.

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