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The global food system is a main source of nitrous oxide (N2O), estimated at 4.1–4.4 Tg N2O-N for 2010. Here, we review this source and assess its mitigation potential. Five mitigation strategies were explored and compared to a ‘business as usual’ (BAU) scenario: firstly, improved crop production; secondly, improved animal production; thirdly, improved manure management; fourthly improved food utilization; and finally, less animal-derived protein in diets. In the BAU scenario, emissions increased to 6.4 Tg for 2030 and 7.5 Tg for 2050. Emission reduction strategies could potentially reduce emissions to 4.1 Tg in 2030 and to 3.3 Tg in 2050, but there is considerable uncertainty in these estimates. In conclusion, packages of coherent strategies may offset the projected increases in N2O emissions from the global food system.

A series of environmental policies have been implemented in the European Union (EU) to decrease nitrogen (N) emissions from agriculture. The Nitrates Directive (ND) is one of the main policies; it aims to reduce nitrate leaching from agriculture through a number of measures. A study was carried out to quantify the effects of the ND in the EU-27 on the leaching and runoff of nitrate (NO3(-)) to groundwater and surface waters, and on the emissions of ammonia (NH3), nitrous oxide (N2O), nitrogen oxides (NO(x)) and dinitrogen (N2) to the atmosphere. We formulated a scenario with and a scenario without implementation of the ND. The model MITERRA-Europe was used to calculate N emissions on a regional level in the EU-27 for the period 2000-2008. The calculated total N loss from agriculture in the EU-27 was 13 Mton N in 2008, with 53% as N2, 22% as NO3, 21% as NH3, 3% as N2O, and 1% as NO(x). The N emissions and leaching in the EU-27 slightly decreased in the period 2000-2008. Total emissions in the EU in 2008 were smaller with implementation of the ND than without the ND, by 3% for NH3, 6% for N2O, 9% for NO(x), and 16% for N leaching and runoff in 2008. However, regional differences were large. The lower emissions with ND were mainly due to the lower N inputs by fertilizers and manures. In conclusion, implementation of the ND decreased both N leaching losses to ground and surface waters, and gaseous emissions to the atmosphere. It is expected that the ND will result in a further decrease in N emissions in EU-27 in the near future, because the implementation of the measures for the ND is expected to become more strict.

SUMMARYNitrogen (N) is an essential element for plants and animals. Due to large inputs of mineral fertilizer, crop yields and livestock production in Europe have increased markedly over the last century, but as a consequence losses of reactive N to air, soil and water have intensified as well. Two different models (CAPRI and MITERRA) were used to quantify the N flows in agriculture in the European Union (EU27), at country-level and for EU27 agriculture as a whole, differentiated into 12 main food categories. The results showed that the N footprint, defined as the total N losses to the environment per unit of product, varies widely between different food categories, with substantially higher values for livestock products and the highest values for beef (c. 500 g N/kg beef), as compared to vegetable products. The lowest N footprint of c. 2 g N/kg product was calculated for sugar beet, fruits and vegetables, and potatoes. The losses of reactive N were dominated by N leaching and run-off, and ammonia volatilization, with 0·83 and 0·88 due to consumption of livestock products. The N investment factors, defined as the quantity of new reactive N required to produce one unit of N in the product varied between 1·2 kg N/kg N in product for pulses to 15–20 kg N for beef.

Agricultural intensification is known to impact the soil biota community. In a previous study, the impact of agricultural intensification on total abundances and functional group structure of major soil biota groups were measured. In this study we address the effects of conversion of extensively managed grassland to arable land on taxonomic diversity at genus and species level of four major soil biota groups (predatory mites, earthworms, enchytraeids, nematodes and bacteria). Vice versa , the effect of agricultural de-intensification (re-establishment of grassland on former arable land) on soil biota taxonomic diversity was also studied. Conversion of an extensively managed grassland to arable land had detrimental effects on taxonomic richness and diversity across taxonomic groups in the short-term, with largest effects on soil biota with larger body size. Effects of arable management were detrimental shortly after conversion. Restoration of grassland resulted in establishment of a species-rich community of nematodes (with partly different species), and recovery of the earthworm community. Predatory mite species were less successful in re-establishing and negative effects on enchytraeid species persisted. When combining the results of Postma-Blaauw et al. (2010) with the present study, we conclude that agricultural intensification resulted in a reduction in abundance and taxonomic diversity of nematodes and bacteria, whereas functional group structure of these groups was little affected. In contrast, predatory mites and earthworms were affected both in functional group structure and in taxonomic diversity. We conclude that agricultural intensification affects total abundances and taxonomic diversity of soil biota in agricultural land, but not necessarily the functional group diversity. Reduced taxonomic diversity may result in reduced resilience to stress, whereas reduced total abundances of microbiota may affect ecosystem functions such as nutrient mineralization.

The acetylene inhibition technique (AIT) is commonly used for the determination of soil denitrification potential (SDP). However, the results obtained with this technique have intrinsic uncertainties. This study aimed at quantifying these uncertainties. A silt loam topsoil from an experimental station was incubated under standard conditions for SDP measurements, with and without acetylene additions. Changes in the concentrations of N2O and N2 in the headspace of incubation vials were monitored during the incubation, using a robotized sampling and analyzing system. Our results showed that the AIT did not completely inhibit the reduction of N2O to N2. As much as 11.7% of the produced N2O was reduced into N2 in the presence of acetylene. We conclude that SDP has to be corrected when determined by the AIT. The procedures used in this study will allow the estimation of correction factors, possibly as function of soil type and environmental conditions.

Catchment riparian areas are considered key zones to target mitigation measures aimed at interrupting the movement of diffuse substances from agricultural land to surface waters. Hence, unfertilized buffer strips have become a widely studied and implemented “edge of field” mitigation measure assumed to provide an effective physical barrier against nitrogen (N), phosphorus (P), and sediment transfer. To ease the legislative process, these buffers are often narrow mandatory strips along streams and rivers, across different riparian soil water conditions, between bordering land uses of differing pollution burdens, and without prescribed buffer management. It would be easy to criticize such regulation for not providing the opportunity for riparian ecosystems to maximize their provision for a wider range of ecosystem goods and services. The scientific basis for judging the best course of action in designing and placing buffers to enhance their multifunctionality has slowly increased over the last five years. This collection of papers aims to add to this body of knowledge by giving examples of studies related to riparian buffer management and assessment throughout Europe. This introductory paper summarizes discussion sessions and 13 selected papers from a workshop held in Ballater, UK, highlighting research on riparian buffers brought together under the EU COST Action 869 knowledge exchange program. The themes addressed are (i) evidence of catchment- to national-scale effectiveness, (ii) ecological functioning linking terrestrial and aquatic habitats, (iii) modeling tools for assessment of effectiveness and costs, and (iv) process understanding enabling management and manipulation to enhance pollutant retention in buffers. The combined understanding led us to consider four principle key questions to challenge buffer strip research and policy.

Coastal and freshwater eutrophication continues to accelerate at sites around the world despite intense efforts to control agricultural P loss using traditional conservation and nutrient management strategies. To achieve required reductions in nonpoint P over the next decade, new tools will be needed to address P transfers from soils and applied P sources. Innovative remediation practices are being developed to remove nonpoint P sources from surface water and groundwater using P sorbing materials (PSMs) derived from natural, synthetic, and industrial sources. A wide array of technologies has been conceived, ranging from amendments that immobilize P in soils and manures to filters that remove P from agricultural drainage waters. This collection of papers summarizes theoretical modeling, laboratory, field, and economic assessments of P removal technologies. Modeling and laboratory studies demonstrate the importance of evaluating P removal technologies under controlled conditions before field deployment, and field studies highlight several challenges to P removal that may be unanticipated in the laboratory, including limited P retention by filters during storms, as well as clogging of filters due to sedimentation. Despite the potential of P removal technologies to improve water quality, gaps in our knowledge remain, and additional studies are needed to characterize the long-term performance of these technologies, as well as to more fully understand their costs and benefits in the context of whole-farm- and watershed-scale P management.

Effectgerichte maatregelen voor vegetaties richten zich doorgaans op het herstel van abiotische factoren in de bodem, zoals nutriënten- en waterhuishouding en tegengaan van verzuring. Lang niet altijd heeft dat het gewenste effect. Het is aannemelijk dat deze milieustress ook tot verstoring van het bodemleven kan leiden. De vraag is in hoeverre een goed functionerend bodemleven van belang is voor het herstel van de vegetatie. Het onderzoek richtte zich op blauwgraslanden en heischrale graslanden, vanwege hun gevoeligheid voor milieustress.

To reduce P losses from agricultural soils to surface water, mitigation options have to be implemented at a local scale. For a cost-effective implementation of these measures, an instrument to identify critical areas for P leaching is indispensable. In many countries, P-index methods are used to identify areas at risk for P losses to surface water. In flat areas, where losses by leaching are dominant, these methods have their limitations because leaching is often not described in detail. PLEASE is a simple mechanistic model designed to simulate P losses by leaching at the field scale using a limited amount of local field data. In this study, PLEASE was applied to 17 lowland sites in Denmark and 14 lowland sites in the Netherlands. Results showed that the simple model simulated measured fluxes and concentrations in water from pipe drains, suction cups, and groundwater quite well. The modeling efficiency ranged from 0.92 for modeling total-P fluxes to 0.36 for modeling concentrations in groundwater. Poor results were obtained for heavy clay soils and eutrophic peat soils, where fluxes and concentrations were strongly underestimated by the model. The poor performance for the heavy clay soil can be explained by the transport of P through macropores to the drain pipes and the underestimation of overland flow on this heavy-textured soil. In the eutrophic peat soils, fluxes were underestimated due to the release of P from deep soil layers.

Nog steeds wordt mest in Nederland verwerkt en vervoerd als afvalproduct, net als bijvoorbeeld bermmaaisel en snoeihout. Die markt zal echter snel veranderen. De komende jaren zal de grondstoffenschaarste toenemen. Het effect is dat veel stoffen die nu nog gelden als afval straks een waardevolle grondstof zullen zijn. Tegelijk zal ook de landbouw daarvoor gaan produceren.

BACKGROUND: An apparently large disparity still exists between developed and developing countries in historical trends of the amounts of nitrogen (N) fertilizers consumed, and the same situation holds true in China. The situation of either N overuse or underuse has become one of the major limiting factors in agricultural production and economic development in China. The issue of food security in N-poor regions has been given the greatest attention internationally. Balanced and appropriate use of N fertilizer for enriching soil fertility is an effective step in preventing soil degradation, ensuring food security, and further contributing to poverty alleviation and rural economic development in the N-poor regions. RESULTS: Based on the China Statistical Yearbook (2007), there could be scope for improvement of N use efficiency (NUE) in N-rich regions by reducing N fertilizer input to an optimal level (=180 kg N ha-1), and also potential for increasing yield in the N-poor regions by further increasing N fertilizer supply (up to 116 kg N ha-1). For the N-rich regions, the average estimated potential of N saving and NUE increase could be about 15% and 23%, respectively, while for the N-poor regions the average estimated potential for yield increase could be 21% on a regional scale, when N input is increased by 13%. CONCLUSION: The study suggests that to achieve the goals of regional yield improvement, it is necessary to readjust and optimize regional distribution of N fertilizer use between the N-poor and N-rich regions in China, in combination with other nutrient management practices.

Niet-kerende grondbewerking geniet een toenemende interesse, omdat het bodemstructuur, organische stof en het vochtvasthoudend vermogen van de bodem kan verhogen. Hierdoor kan erosie van de bodem beperkt worden. Minder ploegen spaart bovendien energie en arbeid en heeft een positief effect op de CO2-vastlegging in organische stof en reductie van emissies (broeikasgassen en mineralen). Minder ploegen draagt daarom bij aan duurzamer bodembeheer voor de teler en de maatschappij.

Direct nitrous oxide (N2O) emissions from fertilized soils are generally estimated using emission factors. However, the emission factors for N2O emission of applied slurry are not well quantified. The effect of slurry application technique on N2O emission was quantified in field experiments in the Netherlands in order to derive N2O emission factors for (shallow) injected and surface-applied cattle and pig slurries. Fluxes of N2O were measured using a closed flux chamber technique and a photo-acoustic infra-red gasmonitor. Fluxes of N2O were measured 64–83 times on grassland on sandy and clay soils and maize land on sandy soil, in the period 2007–2009. There were large differences in total N2O emission between the years, and differences between treatments were not consistent over the years and sites. The average emission factor of all treatments and years (n = 35) was 0.9% of the N applied, which is close to the default IPCC emission factor of 1%. However, the range in emission was large, i.e. from -0.2% to 7.0%. The average emission factor for grassland was 1.7% of the N applied for calcium ammonium nitrate (CAN), 0.4% for shallow injected cattle slurry, and 0.1% for surface-applied cattle slurry. For maize land, the average emission factor for CAN was 0.1% of the N applied, for injected cattle slurry 0.9% and for surface-applied cattle slurry 0.4%. The emission factors for pig slurry applied to maize land were higher than for cattle slurry; 3.6% for injected pig slurry and 0.9% for surface-applied pig slurry. Increasing the N application rate on maize land resulted in higher emission factors for CAN, injected cattle slurry, and injected pig slurry. Concluding, on both grassland and maize land (shallow) injection of slurry increased the average emission factor of N2O in comparison to surface application. Differentiation of N2O emission factors which takes specific factors into account, such as N type and rate and application technique, can improve the quantification of N2O emission from agricultural soils and is needed to derive most efficient options for mitigation.

European Union policy on soil threats and soil protection has prioritized new research to address global soil threats. This research draws on the methodology of Critical Zone Observatories (CZOs) to focus a critical mass of international, multidisciplinary expertise at specific field sites. These CZOs were selected as part of an experimental design to study soil processes and ecosystem function along a hypothesized soil life cycle—from incipient soil formation where new parent material is being deposited, to highly degraded soils that have experienced millennia of intensive land use. Further CZOs have been selected to broaden the range of soil environments and data sets to test soil process models that represent the stages of the soil life cycle. The scientific methodology for this research focuses on the central role of soil structure and soil aggregate formation and stability in soil processes. Research methods include detailed analysis and mathematical modeling of soil properties related to aggregate formation and their relation to key processes of reactive transport, nutrient transformation, and C and food web dynamics in soil ecosystems. Within this program of research, quantification of soil processes across an international network of CZOs is focused on understanding soil ecosystem services including their quantitative monetary valuation within the soil life cycle. Further experimental design at the global scale is enabled by this type of international CZO network. One example is a proposed experiment to study soil ecosystem services along planetary-scale environmental gradients. This would allow scientists to gain insight into the responses of soil processes to increasing human pressures on Earth's critical zone that arise through rapidly changing land use and climate.

In het Nederlandse oppervlaktewater zijn de fosfaatconcentraties vaak te hoog en vormt eutrofiëring een groot probleem. Fosfaatuitspoeling uit landbouwgronden draagt flink bij aan de totale fosfaatbelasting van het oppervlaktewater. Met brongerichte maatregelen, zoals evenwichtsbemesting, zal in sommige delen van het landelijk gebied de hoofddoelstelling van de Kaderrichtlijn Water niet worden gerealiseerd. Hiervoor zijn aanvullende maatregelen nodig, die kunnen bijdragen aan het verbeteren van de chemische waterkwaliteit. We hebben de effectiviteit getest van een drainagebuis omhuld met ijzerzand om fosfaatuitspoeling te verminderen. Deze veldproef is uitgevoerd op een duinzandgrond in het bloembollengebied. Het gemiddelde zuiveringsrendement van de omhulde drainagebuis bedraagt 94 procent. Het omhullen van drainagebuizen met ijzerzand lijkt een veelbelovende maatregel voor het verminderen van fosfaatuitspoeling

Emissions of nitrous oxide (N2O) from managed and grazed grasslands on peat soils are amongst the highest emissions in the world per unit of surface of agriculturally managed soil. According to the IPCC methodology, the direct N2O emissions from managed organic soils is the sum of N2O emissions derived from N input, including fertilizers, urine and dung of grazing cattle, and a constant ‘background’ N2O emission from decomposition of organic matter that depends on agro-climatic zone. In this paper we questioned the constant nature of this background emission from peat soils by monitoring N2O emissions, groundwater levels, N inputs and soil NO3 −–N contents from 4 grazed and fertilized grassland fields on managed organic peat soil. Two fields had a relatively low groundwater level (‘dry’ fields) and two fields had a relatively high groundwater level (‘wet’ fields). To measure the background N2O emission, unfertilized sub-plots were installed in each field. Measurements were performed monthly and after selected management events for 2 years (2008–2009). On the managed fields average cumulative emission equaled 21 ± 2 kg N ha−1y−1 for the ‘dry’ fields and 14 ± 3 kg N ha−1y−1 for the ‘wet’ fields. On the unfertilized sub-plots emissions equaled 4 ± 0.6 kg N ha−1y−1 for the ‘dry’ fields and 1 ± 0.7 kg N ha−1y−1 for the ‘wet’ fields, which is below the currently used estimates. Background emissions were closely correlated with groundwater level (R 2 = 0.73) and accounted for approximately 22% of the cumulative N2O emission for the dry fields and for approximately 10% of the cumulative N2O emissions from the wet fields. The results of this study demonstrate that the accuracy of estimating direct N2O emissions from peat soils can be improved by approximately 20% by applying a background emission of N2O that depends on annual average groundwater level rather than applying a constant value.

Rainfed crop production in northern China is constrained by low and variable rainfall, and by improper management practices. This study explored both the impact of long-term rainfall variability and the long-term effects of various combinations of maize stover, cattle manure and mineral fertiliser (NP) applications on maize (Zea mays L.) yields and water use efficiency (WUE) under reduced tillage practices, at Shouyang Dryland Farming Experimental Station in northern China from 1993 onwards. The experiment was set up according to an incomplete, optimal design, with 3 factors at five levels and 12 treatments including a control with two replications. Grain yields were greatly influenced by the amount of rain during the growing season, and by soil water at sowing. Annual mean grain yields ranged from 3 to 10 t ha-1 and treatment mean yields from 4.2 to 7.2 t ha-1. The WUE ranged from 40 in treatments with balanced nutrient inputs in dry (weather/or soil) years to 6.5 kg ha-1 mm-1 for the control treatments in wet years. The WUE averaged over the 15-year period ranged from 11 to 19 kg ha-1 mm-1. Balanced combination of stover (3000–6000 kg), manure (1500–6000 kg) and N fertiliser (105 kg) gave the highest yield and hence WUE. It is suggested that 100 kg N per ha should be a best choice, to be adapted according to availability of stover and manure. Possible management options under variable rainfall conditions to alleviate occurring moisture stress for crops must be tailored to the rainfall pattern. The potentials of split applications, targeted to the need of the growing crop (response nutrient management), should be explored to further improve grain yield and WUE.

A European Union (EU-27) wide N2O emission estimate for the agricultural sector is presented, using the INTEGRATOR model, combined with detailed GIS-based environmental data and farming data. INTEGRATOR links various modules, calculating NH3, NOx, N2O, CO2, and CH4 emissions from housing and manure storage systems, agricultural and non-agricultural soils and surface waters, while accounting for the interaction between agricultural and non-agricultural systems through an emission-deposition model for NH3 and NOx. This study is limited to N2O emissions from housing and manure storage systems and agricultural soils. All emissions are based on N2O emission factors which depend on environment (weather and soil conditions), land use (grassland, arable land, crop residues), and management (type of manure and fertilizer, etc). We assessed the plausibility by a comparison of calculated present nitrous oxide emissions at country level with those derived by more simple emission factor approaches and detailed ecosystem models. The model was used to assess the impact of various farming practice packages to mitigate N2O emissions. For the agricultural sector of the EU-27, a total N2O emission of 347 kton N2O-N is calculated for the year 2000, which is comparable to other estimates. The overall achievable reduction in N2O emissions with the evaluated mitigation measures is about 25%. For the EU-27, the most effective measures are balanced fertilization and maximum manure application, but this is highly variable per country.

De mondiale emissies van CO2 zijn de afgelopen jaren substantieel gestegen. Een afbuiging van deze trend lijkt noodzakelijk, wil de concentratie in de atmosfeer niet te hoog oplopen. De internationale gemeenschap probeert die te realiseren door stevige reductiedoelstellingen vast te stellen voor de komende tien tot dertig jaar. De inspanningen zijn gericht op terugdringen van emissies, compensatie van de uitstoot door afvang en opslag van CO2 en de omschakeling naar een duurzame energievoorziening.

The Netherlands has a high cumulative mean phosphorus (P) balance. In the 20th century, cumulative mean P surpluses were ca. 4500 kg P2O5/ha. The annual surpluses have levelled off because of manure application limits from 1984 onwards. We report the effect of soil type, land use, and manure policy on changes in soil P of fields in the Netherlands during the 20th century. We used data (> 5 million soil P tests) from the soil analysis laboratory BLGG AgroXpertus. Our results show that soil P has increased on average to fairly high and high ratings. Differences between regions and between land use have remained high from the first records in the 1930s; on arable land the increase continued until the end of our study period while on grassland no changes are evident in the last decades. In general regions with high livestock density have high soil P status. Soil P increased in the order bulbfields

The relationships between potential laboratory indices for plant‐available nitrogen (N) and the plant N uptake in a pot experiment with ryegrass were assessed for 13 mineral soils and 2 peat soils. The methods included aerobic soil incubation, soil incubation in a bioreactor, hot potassium chloride (KCl)–extractable mineral N, 0.01 M calcium chloride (CaCl2)–extractable N, and N loss at heating. The indices for total plant‐available N accounted for 63–93% of the variance in N uptake in a statistical analysis with all soils (n = 15) and 27–89% for the mineral soils (n = 13). Most indices were not a direct quantitative measure of the plant N uptake. The N mineralization indices accounted for 57–86% of the variance in N mineralization for all soils and 5–50% for the mineral soils. Hot KCl‐extractable mineral N and 0.01 M CaCl2–extractable N were the most promising rapid indices for plant‐available N.

Biotic soil parameters have so far seldom played a role in practical soil assessment and management of grasslands. However, the ongoing reduction of external inputs in agriculture would imply an increasing reliance on ecosystem self-regulating processes. Since soil biota play an important role in these processes and in the provision of ecosystem services, biological soil parameters should be an integral part of soil assessment. The general objective of the current study is to investigate to what extent biotic soil parameters provide additional value in soil quality assessment of grassland on sandy soils. We measured abiotic and biotic soil parameters together with process parameters underlying ecosystem services in 20 permanent production grasslands. Cross-validated stepwise regression was used to identify abiotic and biotic soil parameters that explained the soil ecosystem services soil structure maintenance, water regulation, supply of nutrients, and grassland production, respectively. Process parameters underlying the ecosystem service soil structure maintenance such as bulk density and the percentage of sub-angular blocky elements were mainly influenced by SOM and its qualities. The correlations between penetration resistance at 0–10 cm and the percentage of soil crumbs with earthworms suggested a relationship to earthworm activity. Parameters underlying the service of water regulation showed no clear relationship to biotic soil parameters. Water infiltration rate in the field was explained by the penetration resistance at 10–20 cm. Process parameters underlying the service of nutrients’ supply such as the potentially mineralizable C and N were mainly determined by soil total N. The potential C and N mineralization were more related to biotic soil parameters, whereby each parameter was the other’s antithesis. The grassland production without N fertilization viz. the nitrogen supply capacity of the soil measured as N yield, was mainly explained by soil organic matter (SOM) and soil moisture, and to a lesser extent by soil total N. One gram of SOM per kg of dry soil corresponded to 3.21 kg N yield ha −1 , on top of a constant of 15.4 kg N ha −1 . The currently applied calculations in the Dutch grassland fertilization recommendation, underestimated in 85% of the production grasslands, the measured nitrogen supply capacity of the soil by on average 42 kg N ha −1 (31%). This legitimizes additional research to improve the currently applied recommendations for sandy soils. The response of N yield to N fertilization ranged from 35 to 102%. This wide range emphasizes the importance of a better recommendation base to target N fertilizer. The response of N yield to N fertilization was predicted by the total number of enchytraeids, the underlying mechanism of which needs further investigation on different soil types. This knowledge can be important for the optimal use of fertilizer and its consequences for environmental quality.

Greenhouse gas emissions are highly variable in spaceand time. This variability hampers measurements ofgreenhouse gas emissions and hinders the use of landuse and management as mitigation options. We give anoverview of explaining factors of temporal and spatialvariability of greenhouse gas emissions from Dutchlandscapes.CO2 fluxes have a regular annual temporal variability.Temporal variability of N2O emission is characterizedby low background emissions and high peaks that arerelated to precipitation and manure application, whiletemporal variability of CH4 fluxes is very irregular. Spatialvariability of CO2 can be explained using the croptype in agricultural land or the tree species in forests.Spatial variability of N2O and CH4 is strongly influencedby groundwater and management intensity. Additionally,at the landscape scale there is a significant greenhousegas emission from ditches and open water. Thetemporal variability has to be considered in the designof measurement campaigns, while the insight in factorsexplaining the spatial variability of greenhouse gasemissions can help to improve landscape scale estimatesof greenhouse gas emissions and guide managementdecisions for mitigation.

Onderzocht is of mitigatie mogelijk terug te dringen is in de veenweidegebieden en of het door de vastlegging van koolstof in bossen te verhogen is. Daarnaast is bepaald wat de effecten zijn van het Nederlandse landgebruik in de toekomst (scenario's) op de broeikasemissies

The global demand for agricultural products, including food, is rapidly increasing due to population growth and shifts in consumption patterns. The required increase in agricultural production is predominantly to be achieved in countries with relatively low agricultural production levels at present. These are mainly developing countries and countries in transition, the so-called non-Annex I countries of the UNFCCC. However, intensification of agricultural production systems is currently closely linked to high emissions of greenhouse gases notably nitrous oxide (N2O) and methane (CH4). In this paper the relations between population growth, agricultural development and emissions of N2O and CH4 were assessed for 10 non-Annex I countries, viz. China, India, Vietnam, Brazil, Argentina, Mexico, Mongolia, Nigeria, Tanzania and South Africa. We combined FAO data on agricultural production levels, CENSUS data on population statistics and EDGAR data on N2O and CH4 emissions. The projected trends in agricultural production indicate that emissions of N2O and CH4 are expected to increase rapidly in the coming years and will level off from 2040 onwards. The results confirm the positive relation between population increase and increased emissions from agricultural activities for most countries. However, for some countries (South Africa, China and Mexico) this relation was weak or absent. Although numerous factors (e.g. changes in international trade) may have scattered the relation and we were unable to explain this decoupling, it suggests that population growth can be possible without additional emissions. The variation between the different countries and farming systems is however large and mitigation measures at farm-level should be tailored to the wide diversity in environmental conditions, regional customs and farming systems. (C) 2009 Elsevier Ltd. All rights reserved.

This paper presents the results of a survey of stakeholder and scientific expert judgments regarding the impacts of climate change on water management in The Netherlands in 2001. The main methodological findings were put into broader perspective by discussing the role of stakeholder and scientific expert judgment in the context of the Dutch national research programme 'Climate changes Spatial Planning' (CcSP) in the period 2001-2007. We focus on flood risks, and impacts on freshwater resources because they were mentioned most in the 2001 survey. For the flood risks, a high degree of consensus amongst stakeholders and scientific experts was discovered about knowledge, values and aims involved. This was not the case for the impacts of climate change on freshwater resources. The approach, chosen in 2001, enabled the researchers to explore the different opinions regarding the impacts of climate change. It appeared, however, very difficult to prioritize available adaptation options and to formulate cross-sectoral adaptation strategies. Within the CcSP programme, initiated after the 2001 survey, it can be observed that stakeholders become more involved in expert judgements about climate change impacts and adaptation strategies. The interaction between scientists and stakeholders is gradually shifting from a collaborative/consultative approach towards a real participatory approach in the research and design process of combined regional and sectoral adaptation strategies

This study aimed at examining effective sample treatments and spectral processing for an alternate method of soil nitrate determination using the attenuated total reflectance (ATR) of Fourier transform infrared (FTIR) spectroscopy. Prior to FTIR measurements, soil samples were prepared as paste to enhance adhesion between the ATR crystal and sample. The similar nitrate peak heights of soil pastes and their supernatants indicated that the nitrate in the liquid portion of the soil paste mainly responded to the FTIR signal. Using a 0.01-M CaSO4 solution for the soil paste, which has no interference bands in the characteristic spectra of the analyte, increased the concentration of the nitrates to be measured. Second-order derivatives were used in the prediction model to minimize the interference effects and enhance the performance. The second-order derivative spectra contained a unique nitrate peak in a range of 1,400-1,200 cm(-1) without interference of carbonate. A partial least square regression model using second-order derivative spectra performed well (R (2) = 0.995, root mean square error (RMSE) = 23.5, ratio of prediction to deviation (RPD) = 13.8) on laboratory samples. Prediction results were also good for a test set of agricultural field soils with a CaCO3 concentration of 6% to 8% (R (2) = 0.97, RMSE = 18.6, RPD = 3.5). Application of the prediction model based on soil paste samples to nitrate stock solution resulted in an increased RMSE (62.3); however, validation measures were still satisfactory (R (2) = 0.99, RPD = 3.0)

For the purpose of feeding value, drought resistance and nitrogen utilization, other grasses (e.g. Festuca arundinacea and Dactylis glomerata) than the currently widely used perennial rye grass (Lolium perenne) are introduced in dairy farming, either as a monoculture or in a mixture. To study the effect of these grasses on yield and soil chemical and biological quality, the three species were sown in a field experiment in monoculture and in two mixtures. Within two growing seasons, the grass species tested under high soil fertility conditions did not show significant effects on most of the tested soil biological parameters. Only for the mixture of L. perenne and D. glomerata a higher soil NO3− and mineral N content were most probably related to a higher bacterial activity, possibly induced by dying roots of L. perenne. This was the likely cause of the high aboveground dry matter yield of this mixture. The N-efficiencies of the monocultures of L. perenne, F. arundinacea and D. glomerata were not different when only considering the aboveground biomass. In L. perenne and F. arundinacea the total N in root biomass was higher while under D. glomerata the NO3− in the soil was higher. The lower fraction of mineral N to total N for L. perenne, F. arundinacea and the mixture of the two suggests that their organic matter build-up/mineralization ratio was higher than for D. glomerata. Furthermore, the mixture of L. perenne and F. arundinacea showed significantly lower soil mineral N levels than the monocultures of each. We conclude that grassland systems with a mixture of L. perenne and F. arundinacea are more sustainable than the monocultures of each, in terms of reduction of nitrogen losses and the build-up of soil organic matter. D. glomerata should only be used in a mixture in which the companion grass(es) are maintained.

An important but little understood aspect of bioenergy production is its overall impact on soil carbon (C) and nitrogen (N) cycling. Increased energy production from biomass will inevitably lead to higher input of its by-products to the soil as amendments or fertilizers. However, it is still unclear how these by-products will influence microbial transformation processes in soil, and thereby its greenhouse gas (GHG) balance and organic C stocks. In this study, we assess C and N dynamics and GHG emissions following application of different bioenergy by-products to soil. Ten by-products were selected from different bioenergy chains: anaerobic digestion (manure digestates), first generation biofuel by-products (rapeseed meal, distilled dried grains with solubles), second-generation biofuel by-products (nonfermentables from hydrolysis of different lignocellulosic materials) and pyrolysis (biochars). These by-products were added at a constant N rate (150 kg N ha-1) to a sandy soil and incubated at 20 °C. After 60 days, >80% of applied C had been emitted as CO2 in the first-generation biofuel residue treatments. For second-generation biofuel residues this was approximately 60%, and for digestates 40%. Biochars were the most stable residues with the lowest CO2 loss (between 0.5% and 5.8% of total added C). Regarding N2O emissions, addition of first-generation biofuel residues led to the highest total N2O emissions (between 2.5% and 6.0% of applied N). Second-generation biofuel residues emitted between 1.0% and 2.0% of applied N, with the original feedstock material resulting in similar N2O emissions and higher C mineralization rates. Anaerobic digestates resulted in emissions

Only 0·20–0·70 of the fertilizer-nitrogen (N) applied to grassland is taken up in herbage in the harvest directly following application. Residual effects at subsequent harvests can be large but are poorly quantified, and rarely taken into account in current management practices. An increased understanding of N-use efficiency per harvest can improve operational management. This study systematically assessed the residual effects of previously applied N fertilizer on N uptake, dry matter (DM) yield and soil mineral-N (SMN) during the whole of the growing season. It is based on field experiments conducted on peat and mineral soils in 1991–1994. Statistical models were derived for SMN, N uptake and DM yield as a function of previously and freshly applied N fertilizer. There were clear residual effects of previously applied N in later cuts. They were relatively greater at higher levels of N fertilizer. On peat soils, 0·15–0·25 of the N applied was recovered as SMN. On mineral soils the proportion was maximally 0·08. There was a clear relationship between SMN and N uptake in the subsequent cut on mineral soils but not on peat soils. The value of SMN as a tool to adjust fertilizer-N application rates was hence found to be limited. There were clear relationships between the amount of previously applied N and the N uptake in subsequent cuts, on both soil types and over the whole of the growing season. It was concluded that the total amount of previously applied N is a useful indicator for adjusting N-fertilizer application rates

Nederland is verplicht om in het kader van het Kyoto protocol elk jaar broeikasgasemissie aan de UNFCCC te rapporteren. De huidige rapportage is niet zozeer gebaseerd op directe metingen maar op inventarisaties. Emissiebronnen en -putten worden vastgesteld en vermenigvuldigd met emissiefactoren die bepaald zijn voor Nederland. Dit artikel schetst een raamwerk voor verificatie van de nationale rapportages en geeft elementen aan die voor verbetering op termijn kunnen zorgen.

Verschillende meetinstrumenten en technieken worden ingezet om de dynamiek van deze uitwisseling in ruimte en tijd in beeld te krijgen. De metingen moeten vertellen wat de netto broeikasgasbalans van het landschap is en hoe deze zal reageren op een veranderend klimaat

Agriculture is a main contributor of diffuse emissions of N and P to the environment. For N the main loss pathways are NH3-volatilization, leaching to ground and surface water and N-2(O) emissions. Currently, imposing restraints on farm inputs are used as policy tool to decrease N and P leaching to ground water and to surface water, and the same measure is suggested to combat emissions of N2O. The response, however, to these measures largely depends on the soil type. In this study nutrient flows of three dairy farms in The Netherlands with comparable intensity on sand, peat and clay soils were monitored for at least 2 years. The first aim was to provide quantitative data on current nutrient loss pathways. The second aim was to explore the responses in partitioning of the nutrient loss pathways when farm inputs were altered. Mean denitrification rates ranged from 103 kg N ha(-1) year(-1) for the sandy soil to 170 kg N ha(-1) year(-1) for the peat soil and leaching to surface water was about 73 kg N ha(-1) year(-1) for the sandy soil, 15 kg N ha(-1) year(-1) for the clay soil and 38 kg N ha(-1) year(-1) for the peat soil. For P, leaching to surface water ranged from 2 kg P ha(-1) year(-1) for the sandy site to 5 kg P ha(-1) year(-1) for the peat site. The sandy soil was most responsive to changes in N surpluses on leaching to surface water, followed by the peat soil and least responsive was the clay soil. For P, a similar sequence was found. This article demonstrates that similar reductions of N and P inputs result in different responses in N and P loss pathways for different soil types. These differences should be taken into account when evaluating measures to improve environmental performance of (dairy) farms

There is some debate about the likelihood that soil organic carbon (SOC) contents of agricultural land decreases because of global warming and governmental restrictions on animal manure application rates in some countries. Here, we report on changes in the mean SOC contents of the top soils (0–5 cm) of grassland and the top soil (0–25 cm) of arable land in the Netherlands during the period 1984–2004, using a data base with ~ 2 million results of SOC determinations from farmers' fields. The analyses were made for all agricultural land on mineral soils and for agricultural land in 9 regions with distinct differences in mean soil textures and SOC contents (marine and riverine clay, peaty clays, reclaimed peat soils, and Aeolian sand and loess), and land uses (arable land and permanent grassland). Except for the regions with peaty clay and reclaimed peat soils, samples with SOC > 125 g/kg were designated as peat and peaty soils and excluded from the analyses. Mean SOC content of soils under arable land in 2003 ranged from 13 to 22 g/kg for sand, loess and clay soils to 59 g/kg for reclaimed peat soils. Mean SOC content of soils under permanent grassland in 2003 ranged from 22 to 56 g/kg for sand and clay soils. The difference in mean SOC contents between grassland and arable land is in part related to the difference in sampling depth. Mean SOC contents of all mineral soils under grasslands and arable land tended to increase annually by 0.10 and 0.08 g/kg, respectively. We observed large differences in mean trends between regions. Regions with relatively low SOC contents tended to accrue C by up to 0.37 g/kg/year, while regions with relatively high SOC contents (e.g., peaty clays) tended to lose C by up to 0.98 g/kg/year. In conclusion, mean SOC contents of the top part of mineral soils of agricultural land in most regions in the Netherlands tended to increase slightly during the period 1984–2004. This result contrasts with reports from e.g., United Kingdom and Belgium that suggest decreasing C stocks in arable land possibly due to changes in land use and climate.

Global society faces serious “phosphorus challenges” given the scarcity, essentiality, unequal global distribution and, at the same time, regional excess of phosphorus (P). Phosphorus flow studies can be used to analyze these challenges, providing insight into how society (re)uses and loses phosphorus, identifying potential solutions. Phosphorus flows were analyzed in detail for EU-27 and its Member States. To quantify food system and non-food flows, country specific data and historical context were considered. The sectors covered were crop production (CP), animal production (AP), food processing (FP), non-food production (NF) and consumption (HC). The results show that the EU-27 imported 2392 Gg P in 2005, half of which accumulated in agricultural soils (924 Gg) and half was lost as waste (1217 Gg). Net accumulation was 4.9 kg P/ha/year ranging between + 23.2 (Belgium) and - 2.8 (Slovakia). From the system losses, 54% was lost from HC in diverse waste flows and 28% from FP, mainly through incinerated slaughter residues. The largest HC losses (655 Gg) were wastewater (55%), food waste (27%), and pet excreta (11%). Phosphorus recycling rates were 73% in AP, 29% in FP, 21% in HC and ~ 0% in NF. The phosphorus use efficiencies showed that, relative to sector input, about 70% was taken up by crops (CP), 24% was retained in animals (AP), 52% was contained in food products (FP), 76% was stored in non-food materials (NF), and 21% was recycled (HC). Although wide-ranging variation between countries, generally phosphorus use in EU-27 was characterized by relatively (1) large dependency on (primary) imports, (2) long-term accumulation in agricultural soils, especially in west European countries, (3) leaky losses throughout entire society, especially emissions to the environment and sequestered waste, (4) little recycling with the exception of manure, and (5) low use efficiencies, because of aforementioned issues, providing ample opportunities for improvement.

Nederland wil klimaatbestendig worden. De discussie gaat vooral over waterbeheer en waterbeleid als instrumenten om onze samenleving aan te passen aan het veranderende klimaat. De voorgestelde maatregelen zijn daarmee sterk gericht op het watersysteem van Nederland. Maar ook de Nederlandse bodem biedt mogelijkheden voor het beheersen van de gevolgen van klimaatverandering. In dit artikel geven experts van relevante kennis- en onderzoeksinstituten enkele voorbeelden.

Ecosysteemdiensten - meestal gedefinieerd als de voordelen die de mens geniet van ecosystemen - combineert twee werelden: milieu en economie. Het concept bestaat inmiddels al meer dan twintig jaar, maar was tot dusver nog maar weinig bekend. Dat is nu aan het veranderen. Wat hebben ecosysteemdiensten te bieden? Is het een tijdelijke hype of begin van een nieuw tijdperk in het milieudenken? En wat betekent dat dan voor het bodembeheer?

Wereldwijd wordt steeds sterker gepleit voor een verschuiving naar duurzame ontwikkeling. De bewustwording hiertoe werd al lang geleden ingezet door onder andere Rachel Carson in het boek Silent Spring (1962) en de Club van Rome in haar rapport Limits to Growth (1972). In het streven naar verduurzaming van onze activiteiten is recentelijk een nieuw concept naar voren gebracht: Cradle to Cradle (C2C). Vooral in Nederland heeft dit concept veel politici, wetenschappers, ondernemers en het publiek ertoe gebracht na te denken over de praktijk van C2C. Het gaat om vragen als: hoe we producten ontwerpen, produceren, gebruiken en vervolgens opnieuw gebruiken in plaats van ze te dumpen of te vernietigen. Met onder meer projecten rondom de stad Almere, de ontwikkeling van een Happy Shrimp Farm en de opzet van de Floriade door de gemeente Venlo heeft het concept snel ingang gevonden. Het blijkt echter niet gemakkelijk te zijn om in de praktijk de toepassing van C2C op industriële productieprocessen te realiseren.

Wereldwijd neemt de soortenrijkdom af. Dat kan hele ecosystemen ontwrichten. Ook de boer is gebaat bij een grote biodiversiteit, op en vooral in zijn grond.

Wordt de landbouw onevenredig hard getroffen in die gebieden in Nederland waar aan de nitraatconcentratie in het grondwater wordt voldaan? Die vraag probeerden Alterra en de Universiteit Utrecht te beantwoorden in een studie naar de mogelijkheden die de Nitraatrichtlijn biedt om de aanwijzing van nitraatuitspoelingsgevoelige gebieden (kwetsbare zones) en bijbehorende nitraatactieprogramma's te differentiëren naar de landbouw- en milieukundige omstandigheden in de verschillende regio's. Het doel hierachter is een betere aansluiting te krijgen bij de gebiedsgerichte uitwerking van de Kaderrichtlijn Water. De resultaten zijn gebaseerd op literatuurstudie, brainstormsessies, interviews en een bijeenkomst met actoren uit het veld. Een verdere differentiatie is technisch mogelijk via aanwijzing van specifieke kwetsbare zones en het uitzonderen van andere gebieden. Verwacht wordt echter dat het uit te zonderen areaal beperkt zal zijn. Meer perspectief bied een verdergaande (gebiedsgerichte) differentiatie van gebruiksnormen die van toepassing zijn op de aangewezen kwetsbare zones. Nitraatactieprogramma's zijn verder te 'harmoniseren' met stroomgebiedsplannen van de Kaderrichtlijn Water, maar dienen wel als zodanig herkenbaar in stand te blijven.

Bodem beïnvloedt landgebruik maar het landgebruik zelf heeft ook effect op de bodem. Dit leidt tot een continue interactie tussen bodemgebruik, bodemkwaliteit en bodemfuncties. Recente veranderingen in landgebruik in Nederland en consequenties op bodemkwaliteit en bodemfuncties tonen de noodzaak voor een meer dynamische benadering van het begrip bodemkwaliteit aan

This report provides a complete description and background information of the Dutch National System for Greenhouse gas Reporting of the LULUCF sector and the Dutch LULUCF submission under the Kyoto Protocol for the 2013 submission of The Netherlands. The 2013 submission reports greenhouse gas emissions over the year 2011. It includes detailed description of the methodologies used to calculate activity data and emissions and it gives the full text of the NIR-II for KP-LULUCF, as well as a description of the table-by-table methodologies, choices and motivations. In 2011 afforestation and reforestation activities produced a sink of 458.66 Gg CO2 equivalents while deforestation caused an emission of 838.67 Gg CO2 equivalents. These values were based on changes in above-and belowground biomass, dead wood, litter and soil (mineral as well as organic), and agricultural lime application on deforested areas.

As energy crop production on European croplands expands, driven by accelerating consumption of bioenergy, there is a pressing need to evaluate the environmental impacts associated with this production. The present study considers on-going yield increases as a means of boosting agricultural output which results in a limited need to convert nature areas and grasslands to additional cropland. For nine land-use variants, the study evaluates cumulative greenhouse gas emissions, net organic carbon fluxes from the soil, and abated emissions achieved by replacing fossil fuels for transport with biofuels. The main finding is that, in European agriculture, it is possible to combine large-scale biomass production with food production sustained at current levels, with limited direct or indirect land-use changes and while accomplishing significant net greenhouse gas mitigation. Maintaining the current (business as usual) agricultural system results in 4.9 GtCO2-eq. of cumulative emissions by 2030. Intensifi ed food production and energy crop production on freed cropland combined with mitigation measure implementation signifi cantly reduces cumulative emissions for the annual crop groups of oil, starch and sugarbeet to 1.9, 1.5 and 2.1 GtCO2-eq., respectively. By 2030, perennial energy crop production can mitigate cumulative emissions to a large extent, reaching negative emissions (i.e. net sequestration) for grass and wood crops of –3.3 and –4.5 GtCO2-eq., respectively. For the variants compared to the baseline, nitrous oxide emissions will increase modestly due to higher fertilizer-application rates, though at improved effi ciencies per unit crop quantity produced. Emission mitigation results partly from the temporary increase in SOC sequestration though mainly from replacement of fossil resources by biomass resources. The results indicate that research and policy efforts aimed at further increasing productivity can raise the output from existing European croplands while being able to reduce or mitigate emissions significantly.

Western diets are characterised by a high intake of meat, dairy products and eggs, causing an intake of saturated fat and red meat in quantities that exceed dietary recommendations. The associated livestock production requires large areas of land and lead to high nitrogen and greenhouse gas emission levels. Although several studies have examined the potential impact of dietary changes on greenhouse gas emissions and land use, those on health, the agricultural system and other environmental aspects (such as nitrogen emissions) have only been studied to a limited extent. By using biophysical models and methods, we examined the large-scale consequences in the European Union of replacing 25-50% of animal-derived foods with plant-based foods on a dietary energy basis, assuming corresponding changes in production. We tested the effects of these alternative diets and found that halving the consumption of meat, dairy products and eggs in the European Union would achieve a 40% reduction in nitrogen emissions, 25-40% reduction in greenhouse gas emissions and 23% per capita less use of cropland for food production. In addition, the dietary changes would also lower health risks. The European Union would become a net exporter of cereals, while the use of soymeal would be reduced by 75%. The nitrogen use efficiency (NUE) of the food system would increase from the current 18% to between 41% and 47%, depending on choices made regarding land use. As agriculture is the major source of nitrogen pollution, this is expected to result in a significant improvement in both air and water quality in the EU. The resulting 40% reduction in the intake of saturated fat would lead to a reduction in cardiovascular mortality. These diet-led changes in food production patterns would have a large economic impact on livestock farmers and associated supply-chain actors, such as the feed industry and meat-processing sector. © 2014 The Authors.

This report provides a complete description and background information of the Dutch National System for Greenhouse gas Reporting of the LULUCF sector and the Dutch LULUCF submission under the Kyoto Protocol for the 2013 submission of The Netherlands. The 2013 submission reports greenhouse gas emissions over the year 2011. It includes detailed description of the methodologies used to calculate activity data and emissions and it gives the full text of the NIR-II for KP-LULUCF, as well as a description of the table-by-table methodologies, choices and motivations. In 2011 afforestation and reforestation activities produced a sink of 458.66 Gg CO2 equivalents while deforestation caused an emission of 838.67 Gg CO2 equivalents. These values were based on changes in above-and belowground biomass, dead wood, litter and soil (mineral as well as organic), and agricultural lime application on deforested areas.

This project responds to the mismatch between on the one hand a growing demand for biomass on the Dutch and EU energy markets with a limited biomass potential and on the other hand large amounts of biomass and biomass potential currently underutilised in Ukraine. Ukraine itself is seen as a very promising location for sustainable biomass production but is also plagued by economic depression, land degradation, depopulation and high cost for natural gas. The Ukrainian company Phytofuel and the Belgian company Tuzetka recognized the opportunity. Together with Wageningen UR in The Netherlands they started the first experiments with switchgrass and also initiated pelletisation of straw and assessed the opportunity to use available reed stands in the Poltava region. The project aimed to: develop a sustainable business model for pelletizing biomass residues and biomass crops in Ukraine for domestic and NL energy markets; test sustainability of underutilized biomass use and energy crop production on marginal land while avoiding indirect Land Use Changes (iLUC).