Long-term feedbacks result in the recovery of the CO2 sink in a remnant peatland following water table lowering

2020 ◽  
Author(s):  
Joshua Ratcliffe ◽  
David Campbell ◽  
Louis Schipper ◽  
Aaron Wall ◽  
Beverley Clarkson
Keyword(s):  
Water Table ◽  
Carbon Sink ◽  
Ecosystem Respiration ◽  
Chemical Properties ◽  
Sink Strength ◽  
Raised Bogs ◽  
Time Periods ◽  
The Stability ◽  
Pristine Site

<p>Peatland biological, physical and chemical properties change over time in response to the long-term water table position. Such changes complicate predicting the response of peatland carbon stocks to sustained drying. Here we use Eddy Covariance measurements of CO<sub>2</sub> exchange to study the effect of sustained water table lowering on peatland carbon dynamics. We compare measurements from a near-pristine peatland with those of a drying remnant, both raised bogs dominated by <em>Empodisma robustum</em> (Restionaceae), across two different time periods separated by a 16-year interval. We found that the remnant bog was initially a source of CO<sub>2 </sub>following water table lowering. However, the CO<sub>2</sub> sink recovered and strengthened after the 16-year interval between measurements. The increase in CO<sub>2 </sub>sink strength in the remnant bog was primarily due to increased photosynthetic uptake of CO<sub>2</sub>, which exceeded that of the near-pristine site in both time periods. Additionally we found the loss of CO<sub>2 </sub>via ecosystem respiration to have declined with time, however, ecosystem respiration remained elevated compared to the near-pristine site. These trends of increasing photosynthesis and declining ecosystem respiration resulted in the CO<sub>2 </sub>sink in the dry bog reaching half the sink strength of the near-pristine bog. We consider two factors to have been key for the recovery of the CO<sub>2</sub> sink in the remnant bog. These were 1) resilience of the peat-forming plant community to water-table change and 2) the expansion of ericoid shrubs. Our results demonstrate that the peatland carbon sink can recover from drying over a multi-decadal timescale, but questions remain as to the long-term trajectory of dry bogs and the stability of carbon fixed after water table lowering.</p>

scholarly journals From sink to source: long-term (2002-2019) trends and anomalies in net ecosystem exchange of CO2 from a Scottish temperate peatland.

2020 ◽  
Author(s):  
Karen Hei-Laan Yeung ◽  
Carole Helfter ◽  
Neil Mullinger ◽  
Mhairi Coyle ◽  
Eiko Nemitz
Keyword(s):  
Water Table ◽  
Ecosystem Respiration ◽  
Net Ecosystem Exchange ◽  
Growing Season ◽  
Water Table Depth ◽  
Sink Strength ◽  
Summer Drought ◽  
C Cycle ◽  
Dry Spell

<p>Peatlands North of 45˚ represent one of the largest terrestrial carbon (C) stores. They play an important role in the global C-cycle, and their ability to sequester carbon is controlled by multiple, often competing, factors including precipitation, temperature and phenology. Land-atmosphere exchange of carbon dioxide (CO<sub>2</sub>) is dynamic, and exhibits marked seasonal and inter-annual variations which can effect the overall carbon sink strength in both the short- and long-term.</p><p>Due to increased incidences of climate anomalies in recent years, long-term datasets are essential to disambiguate natural variability in Net Ecosystem Exchange (NEE) from shorter-term fluctuations. This is particularly important at high latitudes (>45˚N) where the majority of global peatlands are found. With increasing pressure from stressors such as climate and land-use change, it has been predicted that with a ca. 3<sup>o</sup>C global temperature rise by 2100, UK peatlands could become a net source of C.</p><p>NEE of CO<sub>2</sub> has been measured using the eddy-covariance (EC) method at Auchencorth Moss (55°47’32 N, 3°14’35 W, 267 m a.s.l.), a temperate, lowland, ombrotrophic peatland in central Scotland, continuously since 2002. Alongside EC data, we present a range of meteorological parameters measured at site including soil temperature, total solar and photosynthetically active radiation (PAR), rainfall, and, since April 2007, half-hourly water table depth readings. The length of record and range of measurements make this dataset an important resource as one of the longest term records of CO<sub>2</sub> fluxes from a temperate peatland.</p><p>Although seasonal cycles of gross primary productivity (GPP) were highly variable between years, the site was a consistent CO<sub>2</sub> sink for the period 2002-2012. However, net annual losses of CO<sub>2</sub> have been recorded on several occasions since 2013. Whilst NEE tends to be positively correlated with the length of growing season, anomalies in winter weather also explain some of the variability in CO<sub>2</sub> sink strength the following summer.</p><p>Additionally, water table depth (WTD) plays a crucial role, affecting both GPP and ecosystem respiration (R<sub>eco</sub>). Relatively dry summers in recent years have contributed to shifting the balance between R<sub>eco</sub> and GPP: prolonged periods of low WTD were typically accompanied by an increase in R<sub>eco</sub>, and a decrease in GPP, hence weakening the overall CO<sub>2</sub> sink strength. Extreme events such as drought periods and cold winter temperatures can have significant and complex effects on NEE, particularly when such meteorological anomalies co-occur. For example, a positive annual NEE occurred in 2003 when Europe experienced heatwave and summer drought. More recently, an unusually long spell of snow lasting until the end of March delayed the onset of the 2018 growing season by up to 1.5 months compared to previous years. This was followed by a prolonged dry spell in summer 2018, which weakened GPP, increased R<sub>eco</sub> and led to a net annual loss of 47.4 ton CO<sub>2</sub>-C km<sup>-2</sup>. It is clear that the role of Northern peatlands within the carbon cycle is being modified, driven by changes in climate at both local and global scales.</p>

scholarly journals Insights into CO2 simulations from the Irish Blackwater peatland using ECOSSE model

2020 ◽  
Author(s):  
Alina Premrov ◽  
David Wilson ◽  
Matthew Saunders ◽  
Jagadeesh Yeluripati ◽  
Florence Renou-Wilson
Keyword(s):  
Potential Evapotranspiration ◽  
Carbon Sink ◽  
Ecosystem Respiration ◽  
Research Programme ◽  
Soil Parameters ◽  
Climate Data ◽  
Raised Bog ◽  
Raised Bogs ◽  
Bare Peat

<p><strong>Abstract</strong></p><p>Non-degraded peatlands are known to be important carbon sink; however, if they are exposed to anthropogenic changes they can act as carbon source. This study forms a part of the larger AUGER project (http://www.ucd.ie/auger). It uses the ECOSSE process-based model to predict CO<sub>2</sub> emissions [heterotrophic respiration (Rh)] associated with different peatland management (Smith et al., 2010). The work aims to provide preliminary insights into CO<sub>2</sub> modelling procedures for drained and rewetted sites from Blackwater, the former Irish raised bog. After drainage in 1950’s (due to peat-extraction) and cessation of draining in 1999, the landscape developed drained ‘Bare Peat’ (BP), and rewetted ‘Reeds’ (R) and ‘Sedges’ (S) sites (Renou-Wilson et al., 2019). Modelling of CO<sub>2</sub> from these sites was done using ECOSSE-v.6.2b model (‘site-specific’ mode) with water-table (WT) module (Smith et al., 2010), and default peatland vegetation parameters. The other model-input parameters (including soil respiration, WT and other soil parameters) were obtained from measurements reported in Renou-Wilson et al. (2019). Simulations on drained BP site were run starting from 1950 and on rewetted R and S sites starting from 1999 (which is the year of cessation of drainage). The climate data inputs (2010-2017) were obtained from ICHEC (EPA_Climate-WRF, 2019). The long-term average climate data for model spin-up were obtained from Met Éireann (2012) with potential evapotranspiration estimated by Thornthwaite (1948) method. Daily ecosystem respiration (Reco) data for May/June 2011 to Aug 2011 obtained from raw CO<sub>2</sub> flux measurements (Renou-Wilson et al., 2019) were used. For vegetated sites Rh was estimated from Reco using method explained in Abdalla et al. (2014). Daily CO<sub>2</sub> simulations were compared to Reco for BP site (r<sup>2</sup> =0.20) and to Rh for R site (r<sup>2</sup> = 0.35) and S site (r<sup>2</sup> = 0.55). The preliminary results showed some underestimation of simulated CO<sub>2 </sub>indicating the need for further modelling refinements for satisfactory results. The results from BP site further indicated on the importance of including long-term drainage period (i.e. from 1950 on) because avoiding this step resulted in a large overestimation of predicted CO<sub>2</sub>.</p><p> </p><p><strong>Acknowledgements</strong></p><p>AUGER project is funded under the Irish EPA Research programme 2014-2020.</p><p> </p><p><strong>Literature</strong></p><p>Abdalla, M., et al. 2014. Simulation of CO<sub>2</sub> and attribution analysis at six European peatland sites using the ECOSSE Model. Water Air Soil Pollut 225:2182.</p><p>EPA_Climate-WRF (2019). ERDDAPv.1.82. ICHEC. https://erddap.ichec.ie/erddap/files/EPA_Climate/WRF/</p><p>Met Éireann. 2012. 30 year averages. Met Éireann - The Irish Meteorological Service, Ireland.</p><p>Renou-Wilson, F., et. al. 2019. Rewetting degraded peatlands for climate and biodiversity benefits: Results from two raised bogs. Ecol. Eng. 127:547-560.</p><p>Smith, J., et al. 2010. ECOSSE. User Manual.</p><p>Thornthwaite, C.W. 1948. An approach toward a rational classification of climate. Geog. Review 38, 55-94.</p>

scholarly journals Biochar from co-pyrolysis of urban organic wastes—investigation of carbon sink potential using ATR-FTIR and TGA

2020 ◽  
Author(s):  
Rahul Ramesh Nair ◽  
Moni M Mondal ◽  
Dirk Weichgrebe
Keyword(s):  
Waste Treatment ◽  
Wastewater Treatment Plants ◽  
Carbon Sink ◽  
Chemical Properties ◽  
Treatment Temperature ◽  
Organic Wastes ◽  
Solid Waste Treatment ◽  
The Stability ◽  
Recalcitrance Index

Abstract Urban organic wastes (UOW) strain the infrastructures for solid waste treatment (SWT) in emerging economies. This study investigated biochar gained from three major UOW sources in India—banana peduncles (BP), a fibrous waste, from fruit markets; sewage sludge (SS) from wastewater treatment plants; and anaerobic digestate (AD) from food and market waste processing facilities—in terms of its potential to sequester and become long-term carbon sink in soils. Herein, the chemical properties (using ATR-FTIR) and thermal oxidative stability (using TGA) of biochars derived from these UOW and their three blends were examined. Biochar from SS and AD and the blends were found to possess more ash content, Cl, and alkali and alkaline earth metals (AAEM) than that from BP. The conventional recalcitrance index (R50) could not quantify and compare the stability of these mineral- and ash-rich biochars. Hence, a modified thermal oxidative recalcitrance index (TORi) is proposed. All the biochar from blends prepared at highest treatment temperature of 650 °C shows similar aromaticity. However, biochar from blend of 50% SS, 30%BP, and 20% AD exhibits the highest recalcitrance (TORi = 0.193) to become a long-term carbon sink in soil. More than aromaticity, the influence of Si, Fe, and AAEM on the biochar matrix affects its recalcitrance. Variations in the structural properties and recalcitrance of biochars from blends are attributable to the synergy among their constituents SS, AD, and BP. The determined TORi confirms the potential of biochar from the blends of UOW as a long-term carbon sink.

scholarly journals Drivers of long-term variability in CO<sub>2</sub> net ecosystem exchange in a temperate peatland

2014 ◽  
Vol 11 (10) ◽  
pp. 14981-15018 ◽  
Author(s):  
C. Helfter ◽  
C. Campbell ◽  
K. J. Dinsmore ◽  
J. Drewer ◽  
M. Coyle ◽  
...  
Keyword(s):  
Carbon Sink ◽  
Ecosystem Respiration ◽  
Net Ecosystem Exchange ◽  
Growing Season ◽  
Sink Strength ◽  
Co2 Uptake ◽  
Annual Variability ◽  
Dormant Season ◽  
Carbon Dioxide Co2

Abstract. Land–atmosphere exchange of carbon dioxide (CO2) in peatlands exhibits marked seasonal and inter-annual variability, which subsequently affects the carbon sink strength of catchments across multiple temporal scales. Long-term studies are needed to fully capture the natural variability and therefore identify the key hydrometeorological drivers in the net ecosystem exchange (NEE) of CO2. NEE has been measured continuously by eddy-covariance at Auchencorth Moss, a temperate lowland peatland in central Scotland, since 2002. Hence this is one of the longest peatland NEE studies to date. For 11 yr, the site was a consistent, yet variable, atmospheric CO2 sink ranging from −5.2 to −135.9 g CO2-C m−2 yr−1 (mean of −64.1 ± 33.6 g CO2-C m−2 yr−1). Inter-annual variability in NEE was positively correlated to the length of the growing season. Mean winter air temperature explained 87% of the inter-annual variability in the sink strength of the following summer, indicating a phenological memory-effect. Plant productivity exhibited a marked hysteresis with respect to photosynthetically active radiation (PAR) over the growing season, indicative of two separate growth regimes. Ecosystem respiration (Reco) and gross primary productivity (GPP) were closely correlated (ratio 0.74), suggesting that autotrophic processes were dominant. Whilst the site was wet most of the year (water table depth <5 cm) there were indications that heterotrophic respiration was enhanced by drought, which also depressed GPP. NEE was compared to 5 other peatland sites which have published long-term NEE records. The CO2 uptake rate during the growing season was comparable to 3 other European sites, however the emission rate during the dormant season was significantly higher.

Impacts of long-term warming and enhanced nitrogen and sulfur deposition on carbon sink potential in a boreal peatland

2021 ◽  
Author(s):  
Tuula Larmola ◽  
Liisa Maanavilja ◽  
Heikki Kiheri ◽  
Mats Nilsson ◽  
Matthias Peichl
Keyword(s):  
Global Change ◽  
Wet Deposition ◽  
Carbon Sink ◽  
Ecosystem Respiration ◽  
N Deposition ◽  
Ecosystem Responses ◽  
Gross Photosynthesis ◽  
Poor Fen ◽  
The Individual

&lt;p&gt;In order to assess peatland carbon sink potential under multiple global change perturbations, we examined the individual and combined effects of long-term warming and enhanced nitrogen (N) and sulfur (S) deposition on ecosystem CO&lt;sub&gt;2 &lt;/sub&gt;exchange at one of the longest-running experiments on peatlands, Deger&amp;#246; Stormyr poor fen, Sweden. The site has been treated with NH&lt;sub&gt;4&lt;/sub&gt;NO&lt;sub&gt;3&lt;/sub&gt; (15 times ambient annual wet deposition), Na&lt;sub&gt;2&lt;/sub&gt;SO&lt;sub&gt;4&lt;/sub&gt; (6 times ambient annual wet deposition) and elevated temperature (air +3.6 C) for 23 years. Gross photosynthesis, ecosystem respiration and net CO&lt;sub&gt;2&lt;/sub&gt; exchange were measured weekly during June-August using chambers. After 23 years, two of the experimental perturbations: N addition and warming individually reduced net CO&lt;sub&gt;2&lt;/sub&gt; uptake potential down to 0.3-0.4 fold compared to the control mainly due to lower gross photosynthesis. Under S only treatment ecosystem CO&lt;sub&gt;2&lt;/sub&gt; fluxes were largely unaltered. In contrast, the combination of S and N deposition and warming led to a more pronounced effect and close to zero net CO&lt;sub&gt;2&lt;/sub&gt; uptake potential or net C source. Our study emphasizes the value of the long-term multifactor experiments in examining the ecosystem responses: simultaneous perturbations can have nonadditive interactions that cannot be predicted based on individual responses and thus, must be studied in combination when evaluating feedback mechanisms to ecosystem C sink potential under global change.&lt;/p&gt;

scholarly journals Stability analysis of roadway embankments supported by stone columns with the presence of water table under short-term and long-term conditions

2018 ◽  
Vol 162 ◽  
pp. 01013 ◽  
Author(s):  
Shaymaa Tareq Kadhim ◽  
Ziad Bashar Fouad
Keyword(s):  
Water Table ◽  
Factor Of Safety ◽  
Soft Soil ◽  
Stone Columns ◽  
Stone Column ◽  
Stability Factor ◽  
Short Term ◽  
Long Term Conditions ◽  
The Stability

Use of stone column technique to improve soft foundation soils under roadway embankments has proven to increase the bearing capacity and reduce the potential settlement. The potential contribution of stone columns to the stability of roadway embankments against general (i.e. deep-seated) failure needs to be thoroughly investigated. Therefore, a two-dimensional finite difference model implemented by FLAC/SLOPE 7.0 software, was employed in this study to assess the stability of a roadway embankment fill built on a soft soil deposit improved by stone column technique. The stability factor of safety was obtained numerically under both short-term and long-term conditions with the presence of water table. Two methods were adopted to convert the three-dimensional model into plane strain condition: column wall and equivalent improved ground methods. The effect of various parameters was studied to evaluate their influence on the factor of safety against embankment instability. For instance, the column diameter, columns’ spacing, soft soil properties for short-term and long-term conditions, and the height and friction angle of the embankment fill. The results of this study are developed in several design charts.

scholarly journals Long-term stability of clinically relevant chemistry analytes in pleural and peritoneal fluid

2020 ◽  
Vol 30 (2) ◽  
pp. 234-241
Author(s):  
Lara Milevoj Kopcinovic ◽  
Marija Brcic ◽  
Jelena Culej ◽  
Marijana Miler ◽  
Nora Nikolac Gabaj ◽  
...  
Keyword(s):  
Peritoneal Fluid ◽  
Room Temperature ◽  
Storage Period ◽  
Total Proteins ◽  
Long Term Stability ◽  
Time Periods ◽  
The Stability ◽  
Stability Limits ◽  
Storage Temperatures

Introduction: Our aim was to investigate the stability of clinically relevant analytes in pleural and peritoneal fluids stored in variable time periods and variable storage temperatures prior to analysis. Materials and methods: Baseline total proteins (TP), albumin (ALB), lactate dehydrogenase (LD), cholesterol (CHOL), triglycerides (TRIG), creatinine (CREA), urea, glucose and amylase (AMY) were measured using standard methods in residual samples from 29 pleural and 12 peritoneal fluids referred to our laboratory. Aliquots were stored for 6 hours at room temperature (RT); 3, 7, 14 and 30 days at - 20°C. At the end of each storage period, all analytes were re-measured. Deviations were calculated and compared to stability limits (SL). Results: Pleural fluid TP and CHOL did not differ in the observed storage periods (P = 0.265 and P = 0.170, respectively). Statistically significant differences were found for ALB, LD, TRIG, CREA, urea, glucose and AMY. Peritoneal fluid TP, ALB, TRIG, urea and AMY were not statistically different after storage, contrary to LD, CHOL, CREA and glucose. Deviations for TP, ALB, CHOL, TRIG, CREA, urea and AMY in all storage periods tested for both serous fluids were within the SL. Deviations exceeding SL were observed for LD and glucose when stored for 3 and 7 days at - 20°C, respectively. Conclusions: TP, ALB, CHOL, TRIG, CREA, urea and AMY are stable in serous samples stored up to 6 hours at RT and/or 30 days at - 20°C. Glucose is stable up to 6 hours at RT and 3 days at - 20°C. The stability of LD in is limited to 6 hours at RT.

Net ecosystem exchange of CO2 and ecosystem respiration in two bogs in Estonia along disturbance gradient

2021 ◽  
Author(s):  
Martin Maddison ◽  
Gert Veber ◽  
Ain Kull
Keyword(s):  
Climate Change ◽  
Water Level ◽  
Water Table ◽  
Air Temperature ◽  
Ecosystem Respiration ◽  
Net Ecosystem Exchange ◽  
Growing Period ◽  
Disturbance Gradient ◽  
Study Sites

&lt;p&gt;Northern peatlands are important terrestrial carbon (C) stores, but their ability to sequestrate C is at delicate balance affected by management and also by climate change. The climate change causes less snow pack and warmer winters with faster water table drop in spring and drier summers in most boreal areas. Due to those changes natural peatlands may become C source instead of sink.&lt;/p&gt;&lt;p&gt;This study presents ecosystem respiration (ER) over five-year period and the annual estimates of net ecosystem exchange (NEE) of CO&lt;sub&gt;2&lt;/sub&gt; in Umbusi and Laukasoo in Estonia along disturbance gradient from drained to natural ombrotrophic bog. Both study sites locate next to the active cutaway peatlands. There were four CO&lt;sub&gt;2&lt;/sub&gt; flux measurements plots with three measurements points at different distance from the drainage ditch (10, 50, 100 and 200 m in Umbusi; 3, 40, 50, 125 m in Laukasoo) to form a water table depth and soil moisture gradient on both study sites. ER was measured using opaque static chamber throughout of the year in period 2012-2016. A vented and thermostated transparent plastic chamber with removable opaque cover was used for CO&lt;sub&gt;2&lt;/sub&gt; exchange measurements. NEE measurements occurred biweekly from April to December in 2015, totally were done 648 measurements. NEE was derived from modelling of ER and gross primary production with temperature, photosynthetically active radiation, water level and days of year (as phenological phase) as driving variables.&lt;/p&gt;&lt;p&gt;Annual mean NEE at four different distance from the ditch toward undisturbed area in Umbusi and Laukasoo were 0.37, 0.28, 0.15, 0.08 and 0.44, 0.34, 0.04, 0.21 kg C m&lt;sup&gt;-2&lt;/sup&gt; y&lt;sup&gt;-1&lt;/sup&gt;, respectively. Although mean NEE was positive for all plots on both sites, there were also negative annual NEE values in some points in undisturbed plots (100 and 200 m from the ditch in Umbusi and 50 and 125 m in Laukasoo).&lt;/p&gt;&lt;p&gt;Average water level at four different distance from the ditch toward undisturbed area in Umbusi and Laukasoo during growing period (from the beginning of May to the end of October) in 2015 were -94, -45, -22, -22 and -124, -33, -21, -22 cm, respectively. Monthly mean air temperature and sum of precipitation were not different from the long-term measurements in studied growing period in 2015 while winter was significantly warmer.&lt;/p&gt;&lt;p&gt;Modelled ER remained high for cold period because of higher air temperature in 2015. Due to higher respiration rate from non-frozen peat layer in cold season, more CO&lt;sub&gt;2&lt;/sub&gt; was released back to atmosphere and annually less C was accumulated. Monthly mean air temperature for cold period was 3.5 &amp;#186;C warmer than the long-term average.&lt;/p&gt;

Minerals control phosphorus solubility in long-term-cultivated calcareous soils

Soil Research ◽  
2017 ◽  
Vol 55 (2) ◽  
pp. 182 ◽  
Author(s):  
Mohsen Jalali ◽  
Mahdi Jalali
Keyword(s):  
Crop Production ◽  
Calcareous Soils ◽  
Chemical Properties ◽  
Dicalcium Phosphate ◽  
Equilibration Time ◽  
Soil P ◽  
Wide Range ◽  
The Stability ◽  
Physical And Chemical

Little information is available on phosphorus (P) solubility in long-term cultivated calcareous soils. Improved characterisation of P-containing minerals and soil P species in calcareous soils leads to better management of crop production, water quality and soil quality. In this study, we investigated the solubility relationships of P for 20 surface-soil samples from Hamedan, western Iran, with a wide range of physical and chemical properties. Two equilibration times (0.5 and 168h) were used to evaluate the effect of equilibration times on P activities. We observed up to 67% decrease in mean P concentration when equilibration time was increased from 0.5 to 168h. Solubility diagrams support the stability of hydroxyapatite with 0.5h equilibration and hydroxyapatite and β-tricalcium phosphate with 168h equilibration. Geochemical modelling predicted that dicalcium phosphate, dicalcium phosphate dihydrate and magnesium-P minerals would be unstable and thus would gradually dissolve and supply P in solution in these calcareous soils. The information obtained can be used to predict the behaviour of P and its availability for agricultural crops in calcareous soils.

scholarly journals Long-Term Effects of the Use of Organic Amendments and Crop Rotation on Soil Properties in Southeast Spain

Agronomy ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2363
Author(s):  
Antonio Sánchez-Navarro ◽  
Juan Sánchez-Martínez ◽  
Eva María Barba-Corbalán ◽  
Magdalena Valverde-Pérez ◽  
Aldara Girona-Ruíz ◽  
...  
Keyword(s):  
Crop Rotation ◽  
Carbon Sink ◽  
Organic Amendments ◽  
Chemical Properties ◽  
Soil Management ◽  
Degradation Process ◽  
Long Term Effects ◽  
Forage Maize ◽  
Maize Cultivation

The evolution of soil chemical properties over 20 years was monitored to assess the effects of the change in soil management from a rainfed to an irrigated model and the use of organic amendments and crop rotation. Intensive agriculture has been the activity that has caused most degradation and contamination of this soil. Long-term monitoring of the soil profile made it possible to assess its response to the application of sustainable agricultural techniques intended to offset these effects. Three profiles of the same soil were studied—P1 (1998), P2 (2003), P3 (2017)—to show the evolution in time and space. An incipient degradation process was detected in the first five years, verified by increases in salinity (2.3 dS m−1), exchangeable Na (0.5 g kg−1), and TN (1.3 g kg−1) in P2 in comparison with P1 (1.0, 0.2, and 1.1, respectively). There was also leaching towards the deep horizons for TN (0.4, 0.9, and 0.7 g kg−1 for P1, P2, and P3, respectively), and for assimilable elements such as P (1.1, 6.4, and 3.8), Fe (2.0, 2.1, and 5.6), Mn (0.3, 6.5, and 1.9), Zn (0.3, 0.5, and 0.9), and Cu (0.5, 0.6, and 1.3) (all mg kg−1, for P1, P2, and P3, respectively). Between 2004 and 2017, organic amendments (sheep manure) were reduced by 50%, crop rotation was intensified, and green fertilization and forage maize cultivation were included. As a result, P3 showed an improvement in comparison with P2, with decreases in EC (1.4 dS m−1), exchangeable Na (0.2 g kg−1), and TN (0.8 g kg−1). The change in soil management enhanced some soil functions (carbon sink and chemical fertility) and attenuated soil degradation.

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