•Plaggic Anthrosols and reference soils have similar OC concentrations, radiocarbon age, and SOM composition.•OC in Plaggic Anthrosols is not explained by charred OM from historic plaggen ...amendments.•Sandy agricultural soils in NW and Central Europe accumulate organic matter beyond saturation levels based on organo-mineral associations.•Sandy Plaggic Anthrosols contain high concentrations of OC, likely from specific former vegetation, but stability under current conditions is uncertain.
Carbon sequestration in Plaggic Anthrosols is most often investigated by bulk soil carbon inventories, without considering the form in which the carbon is stored (e.g., particulate or mineral-associated organic matter (OM), its capacity, or its chemical composition). Here, we focus on the unusual high organic carbon (OC) accumulation in sandy Plaggic Anthrosols and adjacent reference soils under agricultural use. In these soils, the mineral fraction ≤20 µm which is commonly assumed to be the major factor for OC stabilization, are very low in mass proportion. Soil organic matter (SOM) physical fractionation was done to evaluate the quantity and quality of OC in the topsoil (Ap horizon). For the fraction ≤20 µm (medium and fine silt-, and clay-sized particles), we measured the concentration of OC and calculated its OC storage capacity and contribution. The OC of the fraction ≤20 µm was radiocarbon-dated and analyzed for its chemical composition by solid-state 13C NMR spectroscopy. The highly sandy (∼90 % sand and coarse silt) soils showed an accumulation of OC much higher than the conventionally calculated saturation level controlled by the proportion of the fraction ≤20 µm. Unexpectedly, Plaggic Anthrosols and the respective reference soils showed similar fractional OC concentrations, radiocarbon ages, and OM composition. The isolated fraction ≤20 µm contained, on average, 81 % of the total soil OC in only 9 % of the corresponding soil mass. All soil fractions ≤20 µm are characterized by a high mean OC concentration in the topsoil (reference soils: 226 ± 66.5 mg OC g−1, Plaggic Anthrosols: 202 ± 59.0 mg OC g−1) with a C/N ratio of 15 on average for both soils. The OM composition of the fraction ≤20 µm was specifically rich in alkyl-C, with unusually low proportions of O-alkyl-C and low contents of aryl-C. The radiocarbon concentration (F14C) indicated that topsoil OM of the ≤20 µm fraction is stored for long time periods with high mean conventional radiocarbon ages (14C) not only for Plaggic Anthrosols (F14C: 0.92 ± 0.04; 14C: 639 yBP) but also for the reference soils (F14C: 0.93 ± 0.04; 14C: 575 yBP) and received low inputs of OC derived from recent photosynthesis. Our data indicate the existence of specific SOM accumulation processes in the investigated sandy agricultural soils, resulting particularly large SOM stocks which cannot be explained by mechanistic association of OM with mineral surfaces. It is not clear, if this inherited OM is stable under present-day soil and management conditions.
We present SPAMS: Simple Parameterization for the Motion of Soils, a model to describe the motion of deformable soils in the Vadose zone, mainly peat and clay, herein called shallow soft soils. The ...SPAMS model estimates the reversible and irreversible vertical component of surface displacement to within sub-centimetre RMSE, using only four parameters: three scaling factors and an integration time. Requiring only meteorological data as an input, its lightweight nature and simple implementation make it a powerful tool when used as a first approximation in inverse problems like those encountered in remote sensing. It has been validated against in-situ data from five test sites in The Netherlands with different Holocene soil strata.
Death, judgement, heaven, and hell are the themes of a late medieval hymn manuscript associated with the Brethren of the Common Life at Zwolle. These same themes constitute the basis of penitential ...meditation in these circles. This book offers a new view on the spirituality of the Modern Devotion and its close connection with music.
The rise in life expectancy is one of the main processes of social change in the 19th century. In the Netherlands, regional differences in life expectancy, and their development, were huge. ...Therefore, studies on average life expectancy or studies, which examine the whole of the Netherlands do not fully capture the differential determinants of this process. This study focuses on social, economic, and geographic differences in life expectancy in 19th-century Overijssel using the Historical Sample of the Netherlands (HSN). Exploiting Cox regression, the influence of several factors on life expectancy are investigated. The article shows that birth cohort, urbanisation, and gender had an important relation with life expectancy in 19th-century Overijssel, while industrialisation, religion, and inheritance customs were not associated with age at death.
A new method is presented to estimate average diffuse aquifer recharge of water table aquifers in temperate climates using time series analysis of water table level fluctuations. An accurate estimate ...of the recharge caused by rainfall requires an accurate estimate of the influence of evaporation. In temperate climates, evaporation imprints a seasonal component in the water table fluctuations. As such, recharge is estimated from time series models fitted to observed heads under the additional constraint that the seasonal harmonic of the observed head is reproduced as the sum of the transformed seasonal harmonics present in precipitation, evaporation, and pumping. An explicit equation is presented, in terms of the model parameters, for the damping and phase shift of the response to the seasonal harmonic of the stresses. Taking into account the seasonal harmonic of the observed heads results in more reliable recharge estimates compared to standard time series analysis. The method is limited to systems that are sufficiently linear and that remain unaltered over the analysis period. Head fluctuations and stresses should contain a seasonal harmonic that can be estimated with accurately. Runoff must be negligible or quantifiable. The method is applied to measured heads obtained from piezometers situated on and around the ice‐pushed sand ridge of Salland in the Netherlands and compares well with recharge estimates based on the saturated zone chloride mass balance.
Key Points
A new approach to estimate average diffuse aquifer recharge from time series analysis of head fluctuations measured in piezometers
The seasonal harmonic of head fluctuations is used as constraint to identify the effect of evaporation accurately
The method results in average recharge estimates without the knowledge of aquifer parameters
The Soil Water Atmosphere Plant (SWAP) model simulates transport of water, solutes, and heat in the vadose zone in interaction with vegetation development. Special features of the model are generic ...crop growth, versatile top boundary conditions, macroporous flow, and interaction of soil water with groundwater and surface water. We discuss typical model applications that have appeared in recent scientific literature. New model developments are explained with respect to the numerical solution of Richards' equation, macroporous flow, evapotranspiration, and interactions with groundwater and surface water. We describe case studies on agricultural water productivity, regional nutrient management, and groundwater conservation by surface water management. Finally we envision model developments with respect to SWAP for the coming 5 to 10 yr.
A semi-quantitative risk assessment is presented for the storage of gas oil in depleted salt caverns in the Twente region, the Netherlands. It is based on a bow-tie model, in which an incident, ...leakage of gas oil from the storage system (cavern and wells), is evaluated by assessing its possible causes and effects. The causes are all the events that may lead to leakage from the storage system. The effects are the consequences of the leakage. It is considered that the most serious of the subsurface risks is contamination of the groundwater due to upward migration of the gas oil to the surface. A unique aspect of our risk assessment is the combination of causes and effects.
The effects of containment/failure are quantified at multiple time scales using a numerical flow model for multiphase flow through porous medium, based on the geohydrological properties of the subsurface of the Twente area. The probability of occurrence of loss of containment/failure (causes) is quantified semi-quantitatively, using the causal relationships between the causes and effects.
Modelling of the leakage shows that, as expected, leakage from the well above the hydrogeological base in the phreatic aquifer produces an immediate risk of contamination of the upper groundwater. However, leakage at a deeper level does not pose a risk of contamination of groundwater, because the low porosity and permeability of the geological layers prevent the upward migration of leaking gas oil. The semi-quantitative approach to the probability of failure finds that for multiple scenarios (e.g. well failure, unstable cavern, high pressure) and in the absence of human intervention, the probabilities of failure are medium to high. If human intervention is assumed, these probabilities of failure diminish considerably, especially those associated with the well. These findings are consistent with those from other hazard studies on storage in salt caverns.
The causes (probabilities of failure) and effects (modelling of leakage) together indicate that for most scenarios the risk is low when human intervention (e.g. monitoring of the well) is assumed.
Notwithstanding our conclusion that the risk of leakage associated with gas oil injection and storage in salt caverns is low, an extensive monitoring plan should be formulated to monitor the containment of the gas oil in the storage system and its long-term stability, to ensure timely human intervention that reduces the risk considerably.
•We assess the risk of storing gas oil in abandoned salt caverns in the Netherlands.•In the bow-tie concept both the causes and the consequences are considered.•Markov Chain analysis was used to quantify the risk.•The risk of groundwater contamination due to leakage from the salt cavern is low.•A major cause of accidents arising from subsurface storage is human error.
Monitoring shallow subsidence in cultivated peatlands van Asselen, Sanneke; Erkens, Gilles; de Graaf, Francis
Proceedings of the International Association of Hydrological Sciences,
04/2020, Letnik:
382
Journal Article, Conference Proceeding
Recenzirano
Odprti dostop
Accurate monitoring of shallow subsidence in cultivated
peatlands is a great challenge. Peat compaction by loading and peat
oxidation by groundwater level lowering are two important processes
...contributing to shallow subsidence in cultivated peatlands, causing an
overall increase in soil wetness over time and hence a lower soil-bearing
capacity and agricultural production. Peat oxidation also causes emission of
CO2 and other greenhouse gasses. Rigorous monitoring techniques are
urgently needed to spatially and temporally map the amount and rate of
subsidence and to monitor effects of measures to reduce subsidence and its
negative impacts on livestock farming and agriculture. Monitoring shallow
subsidence in peatlands is particularly challenging, because subsidence is a
slow and spatially complex process, with average rates in the order of mm yr−1 but with higher rates possibly occurring on shorter timescales.
The desired monitoring system must be able to capture this temporal and
spatial variability, and preferably the contribution of different processes
to total subsidence. The system needs to be applicable (technically- and
financially-speaking) at regional scales, without severely impacting daily
farming activities. To help design and test a subsidence monitoring system
for cultivated peatland areas, four methods to measure subsidence are
applied and assessed in a cultivated peatland in Overijssel (NL), namely
spirit levelling, extensometery, LiDAR, and InSAR. In this paper, we focus on
the levelling and extensometery methods and measurements. Subsidence was
measured since October 2018 at eight livestock farms once every three months
by levelling. In the same period, extensometers have measured vertical
movement of (sub)surface levels hourly at two livestock farms. In addition,
phreatic groundwater levels are continuously monitored. Preliminary results
show vertical movements (up and down) in the order of centimeters on the
timescale of weeks. These movements seem to be related to groundwater level
fluctuations, but also evapotranspiration is expected to contribute to
additional subsidence during the summer period. Because long term net
subsidence is a slow process, additional data collection is needed to assess
the different methods and the temporal and spatial fluctuations in
subsidence on longer timescales. This is vital information to design the
optimal method for monitoring subsidence in cultivated peatlands on large
spatial scales, and to help in selecting effective measures to reduce
subsidence and greenhouse gas emission in peatlands.
► We model nitrogen fluxes and the impact of agricultural measures in a province. ► We quantifies the efficiency of emission control measures in agriculture on the N deposition and critical N load ...exceedances in Natura 2000 sites. ► Most cost-efficient measures were low-emission application and low protein feeding.
This paper quantifies the efficiency of emission control measures in agriculture at landscape scale on the N deposition and critical N load exceedances in Natura 2000 sites. The model INITIATOR2 was run with spatially explicit farm data to predict atmospheric emissions of ammonia. These emissions were input of an atmospheric transport model to assess the N deposition in the Natura 2000 sites. Using the Dutch province of Overijssel as a case study, calculations for the year 2006 show that only 35% of the N deposition in the Natura 2000 sites were caused by agricultural NH3 emissions within the province. Comparatively most cost-efficient measures were low-emission application, followed by measures to reduce the protein content in feed. Relocating farms out of the Natura 2000 sites was very cost inefficient. Since critical N depositions of the Natura 2000 sites in Overijssel are largely exceeded in more than 90% of the area, the evaluated abatement measures were, however, not effective to reduce the area exceeding critical loads when only applied within the province Overijssel. Reductions of N deposition to a level below critical loads can only be achieved with the support of national and international emission reductions.
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