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This Note advocates for the elimination or amendment of the current Dutch Nitrogen Policy. The objective is to provide Dutch farmers with more realistic goals and an extended timeframe to effectively reduce nitrogen emissions on their farms, fostering land improvement and promoting sustainable agricultural practices. In the event of government resistance to these changes, this Note also presents alternative proposals aimed at assisting both farmers and the government in addressing the issue of excess manure and ammonia. These proposals involve repurposing excess manure and ammonia for the use in generating alternative green energy, which can enhance self-sufficiency on farms, produce electricity, and serve as a potential fuel source for future vehicles., I. INTRODUCTION 180 II. MODERNIZATION OF DUTCH FARMING: AN EXAMINATION OF DUTCH HISTORY AND INFLUENTIAL CASES CONTRIBUTING TO PARLIAMENT'S GHG EMISSION REDUCTION LEGISLATION 183 A. FARM MODERNIZATION PRIOR TO 1950 [...]

Context. An appropriate use of the fertiliser technology may lead to a more efficient N absorption and to the reduction of economic and environmental costs. Aims. This study sought to quantify [N.sub.2]O emissions generated from soil and the residual nitrate (N[O.sub.3.sup.-]) up to 2m depth in field conditions in a maize crop under supplementary irrigation and fertilised with two nitrogen (N) sources (UAN and urea) at increasing N rates (0, 80, 160 and 250 kg N [ha.sup.-1]) in the Semi-arid Argentine Pampas. Methods. Throughout the crop cycle, emissions were monitored daily with static chambers during the first week after fertilisation; then sampling frequency was gradually reduced until the end of the experiment. Key results. There were no yield responses to the use of different sources and N rates. Crop N uptake saturated at 80 kg N [ha.sup.-1], reaching 300-310 kg N [ha.sup.-1]. Residual N[O.sub.3.sup.-] increased significantly with the highest rates of N fertiliser. Total [N.sub.2]O emissions differed significantly only among fertiliser rates. The [N.sub.2]O emissions were lower at 80 than at 160 and 250 kg N [ha.sup.-1]. Conclusions. The [N.sub.2]O emissions measured were lower than those calculated by the IPCC, even when only direct emissions were considered. No grain yield increase was observed due to N fertilisation, with a non-limiting supply of N-N[O.sub.3.sup.-] at the beginning of the crop cycle and of N from mineralisation. Implications. This excess of N can generate negative environmental effects due to higher emissions of [N.sub.2]O and residual N-N[O.sub.3.sup.-] that can be leached. Keywords: Argentinean Pampas, environmental effects, greenhouse gases, irrigation, maize yield, nitrate leaching, UAN, urea., Introduction About 80% of cereal and oilseed production in Argentina comes from the Pampean region, mostly soybean, maize and wheat crops (Klein and Vidal Luna 2021). In 2019, maize production [...]

Context. Predicting the nitrogen (N) mineralisation from soil organic matter is a key aid to fertiliser decision-making and improving the N fertiliser use efficiency of a crop. Aims and methods. Field experiments were conducted to assess the amount of inorganic N derived from soil organic matter mineralisation over two seasons (2017-2018 and 2018-2019) across treatments differing in irrigation frequency and amount. During both seasons, the plant line soil in each treatment was sequentially sampled at each irrigation event. Key results. There was an effect of the soil water deficit on the measured accumulated soil inorganic N derived from mineralisation in both measurement years. It was observed that soil inorganic N accumulated in the plant line rather than in other hillside and furrow positions for all soil moisture deficit treatments in both years. In 2017-2018, N accumulated in the plant was significantly greater than the measured accumulated inorganic N (0-300 mm). Conclusions and implications. The sequential soil sampling approach was challenging in irrigated systems and we propose a hybrid measurement of pre-season available soil N and/or plant N uptake in nil N fertiliser plots as a means of estimating N derived from soil organic matter mineralisation. Keywords: cotton, nitrogen mineralisation, vertosol furrow irrigation., Introduction Nitrogen (N) fertiliser use efficiency research in the Australian cotton industry has shown that only 30-60% of the synthetic fertiliser N applied prior to sowing is taken up by [...]

Synchronising nitrogen (N) fertiliser inputs and crop N demand is a major goal in intensive agriculture. However, assessing how much and in which form N arrives at the root surfaces remains a major challenge. Microdialysis has been introduced as a suitable technique to face this challenge and, in this study, we applied microdialysis to assess in situ diffusive N fluxes in a temperate agricultural field. Additionally, soil N concentrations were estimated by water extractions to compare different approaches for measuring plant-available N. Concentrations and diffusive fluxes of N did not correlate and differed significantly regarding the relative contribution of different N forms to total N. Nitrate was the dominant N form (~80%) in water extracts while diffusive fluxes of N[O.sub.3.sup.-], N[H.sub.4.sup.+] and free amino acids were similar (38%, 34% and 28%, respectively). Extractable N and diffusive N fluxes varied strongly across the entire field, with a higher variability at smaller scales. Our results suggest that diffusive N fluxes are affected by a complex network of abiotic and biotic factors, either directly controlling diffusion or indirectly by affecting soil N production and consumption rates. We therefore recommend that future efforts should be directed into including such factors in more complex modelling approaches to assess plant-available N in agricultural fields. Keywords: agriculture, amino acids, corn (Zea mays), inorganic nitrogen, microdialysis, nitrogen fertiliser, soil diffusive fluxes, soil extraction., Introduction In agricultural ecosystems, a key objective for improving the nutrient use efficiency of crops is to closely match soil nitrogen (N) supply with the plants' N demand (Matson et [...]

The intensive application of inorganic nitrogen underlies marked increases in crop production, but imposes detrimental effects on ecosystems.sup.1,2: it is therefore crucial for future sustainable agriculture to improve the nitrogen-use efficiency of crop plants. Here we report the genetic basis of nitrogen-use efficiency associated with adaptation to local soils in rice (Oryza sativa L.). Using a panel of diverse rice germplasm collected from different ecogeographical regions, we performed a genome-wide association study on the tillering response to nitrogen--the trait that is most closely correlated with nitrogen-use efficiency in rice--and identified OsTCP19 as a modulator of this tillering response through its transcriptional response to nitrogen and its targeting to the tiller-promoting gene DWARF AND LOW-TILLERING (DLT).sup.3,4. A 29-bp insertion and/or deletion in the OsTCP19 promoter confers a differential transcriptional response and variation in the tillering response to nitrogen among rice varieties. The allele of OsTCP19 associated with a high tillering response to nitrogen is prevalent in wild rice populations, but has largely been lost in modern cultivars: this loss correlates with increased local soil nitrogen content, which suggests that it might have contributed to geographical adaptation in rice. Introgression of the allele associated with a high tillering response into modern rice cultivars boosts grain yield and nitrogen-use efficiency under low or moderate levels of nitrogen, which demonstrates substantial potential for rice breeding and the amelioration of negative environment effects by reducing the application of nitrogen to crops. OsTCP19 is a modulator of the tillering response to nitrogen in rice, and introgression of an allele of OsTCP19 associated with a high tillering response into modern rice cultivars markedly improves their nitrogen-use efficiency., Author(s): Yongqiang Liu [sup.1] [sup.2] , Hongru Wang [sup.1] , Zhimin Jiang [sup.1] , Wei Wang [sup.1] , Ruineng Xu [sup.3] [sup.4] , Qihui Wang [sup.5] , Zhihua Zhang [sup.1] [...]

Herbivores impact soil biogeochemical processes, often increasing nutrient cycling rates under high nutrient availability and decreasing nutrient cycling rates under low nutrient availability. These patterns are far from universal, and interactions between habitat fertility and herbivore effects are under continuing investigation. By sampling inside and outside a network of deer exclosures, we determined deer browsing effects on temperate forest soil nitrogen (N) and carbon (C) cycling along a gradient of soil and litter C-N ratios across our network of sites. Deer browsing increased net N mineralization rates in high nutrient environments and decreased N mineralization rates in low nutrient environments, whereas browsing decreased C[O.sub.2] respiration rates in high nutrient environments and increased C[O.sub.2] respiration rates in low nutrient environments. Differences in deer browsing effects on soil processes could be explained by plant responses to herbivory across gradients of resource availability. To our knowledge, our study is one of the first to show that deer browsing can have significant effects on net N mineralization and C respiration in temperate forest soils and that the direction and magnitude of deer browsing effects on soil N and C cycling vary across fertility gradients. Key words: soil biogeochemistry, herbivory, deer browsing, nitrogen, nutrient cycles. Les herbivores ont un impact sur les processus biogeochimiques du sol: ils augmentent souvent le taux de recyclage des nutriments lorsque ceux-ci sont tres disponibles et le reduisent lorsqu'ils sont peu disponibles. Ces patrons sont loin d'etre universels et les etudes sur les interactions entre la fertilite de l'habitat et les effets des herbivores se poursuivent. En echantillonnant a l'interieur et a l'exterieur d'un reseau d'exclos pour le chevreuil, nous avons determine les effets du broutage par les chevreuils sur le recyclage de l'azote (N) et du carbone (C) dans le sol de la foret temperee le long d'un gradient de rapports C-N dans le sol et la litiere dans notre reseau de stations. Le broutage des chevreuils a augmente le taux de mineralisation nette de N dans les milieux riches en nutriments et reduit le taux de mineralisation de N dans les milieux pauvres en nutriments, tandis qu'il a diminue le taux de respiration du C[O.sub.2] dans les milieux riches en nutriments et augmente le taux de respiration du C[O.sub.2] dans les milieux pauvres en nutriments. Les differences dans les effets du broutage sur les processus du sol pourraient s'expliquer par les reponses des plants au broutage en fonction des gradients de disponibilite des ressources. A notre connaissance, notre etude est une des premieres a montrer que le broutage du chevreuil peut avoir des effets significatifs sur la mineralisation nette de N et la respiration du C dans les sols de la foret temperee et que la direction et l'ampleur des effets du broutage des chevreuils sur le recyclage de N et C varient en fonction des gradients de fertilite. [Traduit par la Redaction] Mots-cles: biogeochimie du sol, herbivore, broutage du chevreuil, azote, cycles des nutriments., Introduction Herbivores are known to have strong effects on ecosystem processes such as primary production (Milchunas and Lauenroth 1993), fire regimes (Van Langevelde et al. 2003; Holdo et al. 2009), [...]

This paper explores the importance of the N loss pathways relative to the immobilisation and soil mineral N supply during a cotton season. Despite using an agronomic practice of splitting urea application to reduce losses and an optimal rate (232 kg urea-N [ha.sup.-1]) for the experiment, the average fertiliser recovery was 32%, which indicates that soil N mineralisation is a key source of N for irrigated cotton production systems. A large amount of the fertiliser (62 kgN[ha.sup.-1]) was immobilised in the soil at the end of the season and during the season the soil supplied 159 kg N [ha.sup.-1] to the plant via mineralisation. During the season, large N losses occurred from the field via the atmospheric, deep drainage and surface run-off pathways (143 kgN[ha.sup.-1]). The losses occurred directly after fertilisation, predominantly at the start of the season when the majority of the urea fertiliser was applied (180 kg urea-N [ha.sup.-1]). This indicates that the fonn, placement and timing of the fertiliser did not synchronise with soil and crop N dynamics and irrigation practice. Over the course of the measurement season, based on the N inputs, losses and storage budget, a 42kgN[ha.sup.-1] soil deficit was observed. Further longer term work is required to quantify the magnitude and significance of the soil N stock across different systems., Introduction Synthetic nitrogen fertiliser is a critical component in modern agriculture and underpins the green revolution. As a result, the production and consumption of synthetic nitrogen fertiliser has grown exponentially [...]

Laboratory incubation studies were used to investigate whether and how variability of different plant litters modifies the mobility of nitrogen in soil. Fallen plant foliage from native New Zealand plants of diverse fibre and nutrient content were selected, with C:N ratios ranging from 14 to 102. Different litters provided substantially different inputs of macro- and micronutrients to soil that affected the mobility ofN. Both fibre content and C :N ratios were influential. A primary effect of litter addition to soil was modification of pH, largely attributable to calcium enrichment. Nitrate in soil was reduced by up to 85% following litter amendments. Incorporation of five native plant litters into soil significantly suppressed emissions of nitrous oxide. We interpret these findings in the context of plant residues from naturalistic planting on the borders of farm paddocks that may play a role in tightening the N cycle and restricting spillover of nitrogen pollutants to the wider environment. Additional keywords: agrobiodiversity, agroecology, nitrate, nitrous oxide, soil amelioration., Introduction Plant litter input and its decomposition modifies the physical, chemical and biological properties of soil, protecting soil from erosion (Marshall et al. 1996; Li el al. 2014), mediating soil [...]

Abstract: The Sandhill Fen reclamation watershed, commissioned by Syncrude Canada Ltd., is the first attempt to reclaim a self-sustaining peat-forming wetland on a previously mined area. Here, we quantified net [...]

The potential for elevated nitrous oxide ([N.sub.2]O) losses is high in subtropical cereal cropping systems in northeast Australia, where the fertiliser nitrogen (N) input is one single application at or before planting. The use of urea coated with the nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) has been reported to substantially decrease [N.sub.2]O emissions and increase crop yields in humid, high-intensity rainfall environments. However, it is still uncertain whether this product is similarly effective in contrasting soil types in the cropping region of north-east Australia. In this study the grain yield response of sorghum (Sorghum bicolor L. Moench) to rates of fertiliser N applied as urea or urea coated with DMPP were compared in crops grown on a Vertisol and an Oxisol in southern Queensland. Seasonal [N.sub.2]O emissions were monitored on selected treatments for the duration of the cropping season and the early stages of a subsequent fallow period using a fully automated high-frequency greenhouse gas measuring system. On each soil the tested treatments included an unfertilised control (0 kg N [ha.sup.-1]) and two fertilised treatments chosen on the basis of delivering at least 90% of seasonal potential grain yield (160 and 120 kg N [ha.sup.-1] on the Vertisol and Oxisol respectively) or at a common (suboptimal) rate at each site (80 kg N [ha.sup.-1]). During this study DMPP had a similar impact at both sites, clearly inhibiting nitrification for up to 8 weeks after fertiliser application. Despite the relatively dry seasonal conditions during most of the monitoring period, DMPP was effective in abating [N.sub.2]O emissions on both soils and on average reduced seasonal [N.sub.2]O emissions by 60% compared with conventional urea at fertiliser N rates equivalent to those producing 90% of site maximum grain yield. The significant abatement of [N.sub.2]O emissions observed with DMPP, however, did not translate into significant yield gains or improvements in agronomic efficiencies of fertiliser N use. These results may be due to the relatively dry growing season conditions before the bulk of crop N acquisition, which limited the exposure of fertiliser N to large losses due to leaching and denitrification. Additional keywords: automated greenhouse gas measuring system, denitrification, nitrogen response., Introduction Vertisols and Oxisols are among the main soil types in subtropical regions (Buol and Eswaran 1999; Syers et al. 2001) and contribute significant amounts of global cereal production (Sant' [...]

Nitrogen (N) fertiliser is a major source of atmospheric nitrous oxide ([N.sub.2]O), and over recent years there has been growing evidence for a non-linear, exponential relationship between N fertiliser application rate and [N.sub.2]O emissions. However, there is still a high level of uncertainty around the relationship of N fertiliser rate and [N.sub.2]O emissions for many cropping systems. We conducted year-round measurements of [N.sub.2]O emission and lint yield in four N-rate treatments (0, 90, 180 and 270 kg N [ha.sup.-1]) in a cotton-fallow rotation on a black vertosol in Australia. We observed a non- linear exponential response of [N.sub.2]O emissions to increasing N fertiliser rates with cumulative annual [N.sub.2]O emissions of 0.55, 0.67, 1.07 and 1.89 kg N [ha.sup.-1] for the four respective N fertiliser rates, but no N response to yield occurred above 180 kg N [ha.sup.-1]. The annual [N.sub.2]O emission factors induced by N fertiliser were 0.13, 0.29 and 0.50% for the 90, 180 and 270 kg N [ha.sup.-1] treatments respectively, significantly lower than the IPCC Tier 1 default value of 1.0%. This nonlinear response suggests that an exponential [N.sub.2]O emissions model may be more appropriate for estimating emission of [N.sub.2]O from soils cultivated to cotton in Australia. It also demonstrates that improved agricultural N-management practices can be adopted in cotton to substantially reduce [N.sub.2]O emissions without affecting yield. Received 20 November 2014, accepted 8 October 2015, published online 6 July 2016, Introduction Nitrous oxide ([N.sub.2]O) contributes to the greenhouse effect due to its high global warming potential (nearly 300 times greater than carbon dioxide over a 100-year horizon) and is also [...]

In organic farming winter cereals, as cover crops, provide nutrients, when they return to soil as crop residues. The fate of N deriving from two decomposing [sup.15]N-labelled winter cereals, with or without the supply of an organic N fertiliser, was studied in a field experiment. The stabilisation of residues N in soil aggregates and the portion lost from the system were also evaluated. Barley or triticale residues were incubated alone or with hydrolysed leather (L) in mesocosms over one year. The residues derived N was measured in soil and in soil aggregate size fractions >250 µm (macroaggregates, macro); 53-250 µm (microaggregates, micro); Additional keywords: [sup.15]N-labelled crop residues; N release; N losses; Organic N fertilizer; Soil aggregate fractions., Introduction Organic farming systems rely on ecologically based practices and the fundamental components and natural processes of ecosystems. Soil organism activities, nutrient cycling and species distribution and competition are used [...]

The application of wastes from the wine-distillery industry as source of organic matter and nutrients could be a good option of agricultural management. This study is focused on soil nitrogen (N) mineralisation after addition of compost derived from this industry at different doses (7, 13 and 20 t [ha.sup.-1]). An aerobic soil incubation in controlled conditions was carried out to study N mineralisation from the soil-compost mixture as well as isolating the compost from the soil. The data were fitted to a non-linear regression obtaining low values of potentially mineralisable N ([N.sub.0]) and constants of mineralisation (k) (from 81 to 104 m g [kg.sup.-1] and from 0.008 to 0.013 L [day.sup.-1] for the soil-compost mixtures, and from 42 to 71 mg [kg.sup.-1] and from 0.009 to 0.015 L [day.sup.-1] for the increasing doses of compost) which indicates that it is a mature compost very resistant to mineralisation. Nitrogen mineralised (NM) in the field during two growing seasons (2011 and 2012) of a melon crop was calculated through a N balance, taking into account N inputs and outputs in the soil-plant system. NM in the unamended plots accounted to 31 k g [ha.sup.-1] and 24 kg [ha.sup.-1] in 2011 and 2012, respectively, and increased proportionally to the dose of compost applied until 113 kg [ha.sup.-1] and 98 k g/ha in the consecutive years. The constants of mineralisation obtained in the laboratory were adjusted by field temperatures to predict NM in the field and a general overestimation was observed. The best estimates were obtained when considering the mixture of soil and compost, which reflects the important role of the soil to evaluate N mineralisation caused by the addition of organic wastes., Introduction Spain is the third largest wine producer in the world, producing more than 3 million tons of wine each year (FAO 2012). During the winemaking process, solid residues (e.g. [...]

Patterned ground is a characteristic landscape form in arid zones across the globe and is caused by the redistribution of runoff. The vegetation is concentrated in groves, which receive runoff water from the bare soil surface of the intergroves. Despite many soil chemical and physical investigations, biogeochemical cycles are not described for this landscape form. This study focuses on the distinct features of the nitrogen (N) and carbon (C) cycle in intergrove and grove areas of chenopod pattern-ground soils of the Australian rangelands. The N concentration of grove soils is low compared with the intergrove soil because of a close link between the N cycle in the topsoil and the plant primary production. In grove soils, denitrification including emission of [N.sub.2]O dominated the N cycle, whereas in intergrove soils, abiotic [N.sub.2]O uptake is the sole fate of atmospheric [N.sub.2]O. The intergrove soils appear to be generally poor in bacterial quantity and diversity, and lacking denitrification by bacteria, which has an impact on the C cycle as well. Production of C[O.sub.2] and consumption of C[H.sub.4] were substantially lower than grove soils. There was partitioning ofkcy biogeochemical processes between the intergrove and grove soils, which results in a spatially decoupled soil N and C cycle in arid chenopod, pattern-ground ecosystems. Received 24 July 2014, accepted 19 September 2014, published online 27 January 2015, Introduction Shrub-steppe covers 7.5% (451 000 [km.sup.2]) of Australia's arid and semi-arid rangelands, and is dominated by various annual and perennial species of the family Chenopodiaceae (Leigh 1972). These chenopod [...]

Forest fertilization with nitrogen (N) has several benefits to society such as increased wood production and carbon sequestration. There are, however, concerns about N leakage, particularly following clear-cutting. The forest-floor vegetation may increase the N retention of forest ecosystems; however, very few studies have quantified the amount of vegetation required. We studied the relationship between vegetation cover and risk of N leakage, estimated by the amounts of ammonium-N and nitrate-N retained on ion-exchange capsules in the soil, during 4 years following the clear-cutting and harvesting of logging residues in a previously fertilized forest in southern Sweden. Previous fertilization increased the amount of nitrate-N captured on the capsules, whereas the amount of ammonium-N decreased. The vascular vegetation cover increased from almost zero to approximately 25% independent of fertilization. The amount of ammonium-N and nitrate-N retained on the capsules was already reduced by 50%-75% at 20% vegetation cover, and by 30%-40% cover, it approached zero, independent of the number of years since clear-cutting. The vegetation may impede tree-seedling establishment, implying a trade-off between seedling growth and N-retention capacity. However, our results indicate that maximum N retention may be achieved at a relatively low vegetation cover, which could be accomplished with less intrusive scarification methods than currently used. Key words: nutrient leakage, nitrogen, forest fertilization, ground vegetation, immobilization. La fertilisation forestiere avec de l'azote (N) procure de nombreux benefices a la societe, notamment une augmentation de la production de bois et de la sequestration de carbone. Cependant, le lessivage de N suscite des inquietudes, particulierement a la suite d'une coupe totale. La vegetation au sol peut augmenter la retention de N dans les ecosystemes forestiers, mais tres peu d'etudes ont evalue la quantite de vegetation necessaire pour y arriver. Nous avons etudie la relation entre la couverture de vegetation et le risque de lessivage de N; cette relation a ete estimee en fonction des quantites de N sous forme d'ammonium et de nitrate retenues sur des capsules d'echange ionique inserees dans le sol au cours des quatre annees suivant une coupe totale avec enlevement des residus de coupe dans des forets prealablement fertilisees du sud de la Suede. La fertilisation a augmente la quantite de nitrate captee par les capsules, alors que la quantite d'ammonium a decru. La couverture des plantes vasculaires est passee de pres de zero a environ 25% et ce, independamment de la fertilisation. Les quantites d'ammonium et de nitrate retenues sur les capsules ont ete reduites de 50%-75% avec une couverture de vegetation de 20%; lorsque la couverture atteignait 30%-40%, les quantites etaient presque nulles, independamment du temps ecoule depuis la coupe totale. La vegetation au sol peut nuire a l'etablissement des semis d'arbres, ce qui signifie qu'on doit faire un compromis entre la croissance des semis et la capacite de retention de N. Cependant, nos resultats indiquent qu'on peut obtenir une retention maximale de N avec une couverture de vegetation relativement faible, ce qui peut etre accompli par l'utilisation de methodes de scarifiage moins intrusives que les methodes courantes. [Traduit par la Redaction] Mots-cles : lessivage d'elements nutritifs, azote, fertilisation forestiere, vegetation au sol, immobilisation., Introduction The limitation of nutrient losses to ground and surface water is a prerequisite for the sustainable utilization of forest soils and the avoidance of eutrophication (Binkley et al. 1999). [...]