Organic Fertilization in Maize Cropping Systems: Measures to Reduce N Losses

A special issue of Agronomy (ISSN 2073-4395). This special issue belongs to the section "Innovative Cropping Systems".

Deadline for manuscript submissions: closed (15 December 2020) | Viewed by 42862

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Faculty of Agricultural Science & Landscape Architecture, University of Applied Science Osnabrück, 49090 Osnabrück, Germany
Interests: soil analysis; crop production; plant nutrition; soil sensing; fertilizer recommendation
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Special Issue Information

Dear colleagues,

Maize is one of the most important crops around the world. It is used as staple food for humans as well as a major source of both grain feed and silage fodder for livestock, widely used as a feedstock for the production of ethanol fuel and for methane production in biogas plants. Starch from maize can also be made into plastics and many other chemical products.

In many regions, organic fertilizers (e.g., products derived from human and animal excreta, composted materials, and crop residues) are a significant nutrient source in maize production systems. However, maize is a crop with a rather low growth rate during the early seedling stage after germination, and especially nitrogen losses from organic fertilizers might be substantial during this period. In many field situations, ammonia emissions to the atmosphere shortly after application of organic fertilizers and nitrate leaching after microbial mineralization/nitrification has occurred are obviously the most predominant processes. In recent decades, different approaches have been developed to minimize these losses and introduced into farm practice.

This Special Issue intends to give a broad overview focusing on pot and field experiments with maize where various technical measures (e.g., band application, injection) or usage of additives (e.g., acids, nitrification inhibitors) have been investigated to reduce any kind of N losses from applied organic fertilizers. Furthermore, review papers as well as opinion statements are welcome.

Prof. Dr. Hans-Werner Olfs
Guest Editor

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Keywords

  • maize
  • organic fertilizers
  • nitrification inhibitors
  • urease inhibitors
  • greenhouse gas emissions
  • ammonia volatilization
  • nitrate leaching
  • application techniques
  • liquid manures
  • biogas residues

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Published Papers (11 papers)

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Editorial

Jump to: Research, Review

4 pages, 195 KiB  
Editorial
Organic Fertilization in Maize Cropping Systems: Measures to Reduce N Losses
by Hans-Werner Olfs
Agronomy 2021, 11(4), 793; https://doi.org/10.3390/agronomy11040793 - 17 Apr 2021
Cited by 3 | Viewed by 2099
Abstract
Maize is one of the most important crops around the world [...] Full article

Research

Jump to: Editorial, Review

14 pages, 3525 KiB  
Article
Precision Injection of Dairy Sludge on Crop Yield and N and P Uptake in Juvenile and Mature No-Till Silage Corn
by Derek E. Hunt and Shabtai Bittman
Agronomy 2021, 11(2), 370; https://doi.org/10.3390/agronomy11020370 - 19 Feb 2021
Cited by 3 | Viewed by 2439
Abstract
Starter mineral fertilizer is used by famers to provide phosphorus (P) and nitrogen (N) to emerging corn (Zea mays) plants. Recent studies have shown that dairy slurry can replace mineral fertilizer provided it is precisely positioned close to the corn rows. [...] Read more.
Starter mineral fertilizer is used by famers to provide phosphorus (P) and nitrogen (N) to emerging corn (Zea mays) plants. Recent studies have shown that dairy slurry can replace mineral fertilizer provided it is precisely positioned close to the corn rows. This 5-year study examined the multi-year effect of precision injected sludge, the thick fraction separated from dairy slurry, on growth and nutrient uptake at the 6-leaf stage and final harvest of no-till corn. The sludge was first injected 15 cm deep and the corn planted < 10 cm from the sludge furrow at least 3 days later. Sludge provided sufficient P for both early growth and full season growth. At final harvest with equivalent total N and P rates (32P 250N treatments), fertilizer and sludge had similar maximum yields (17.9 and 17.4 t ha−1, respectively) and P uptake (26 and 25 kg ha−1, respectively) but fertilizer had higher N uptake than sludge (200 and 162 kg ha−1). N uptake and recovery N use efficiency was greater for sludge than fertilizer based on equivalent min.-N which suggests crop benefits in the sludge other than min-N and P. The study shows that precisely injected dairy sludge can obviate the need for starter mineral fertilizer, and this may help to alleviate P surpluses on dairy farms. This practice also provides a use on dairy farms for the separated solids fraction remaining after the thin fraction is decanted and applied as the primary N source to grass. Full article
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18 pages, 2019 KiB  
Article
N2O and NO Emissions as Affected by the Continuous Combined Application of Organic and Mineral N Fertilizer to a Soil on the North China Plain
by Deyan Liu, Heyang Sun, Xia Liao, Jiafa Luo, Stuart Lindsey, Junji Yuan, Tiehu He, Mohammad Zaman and Weixin Ding
Agronomy 2020, 10(12), 1965; https://doi.org/10.3390/agronomy10121965 - 14 Dec 2020
Cited by 18 | Viewed by 3336
Abstract
A field experiment was conducted to evaluate the influence of the continuous application of organic and mineral N fertilizer on N2O and NO emissions under maize and wheat rotation on the North China Plain. This study included eight treatments: no fertilizer [...] Read more.
A field experiment was conducted to evaluate the influence of the continuous application of organic and mineral N fertilizer on N2O and NO emissions under maize and wheat rotation on the North China Plain. This study included eight treatments: no fertilizer (control); mineral N fertilizer (Nmin) at a rate of 200 kg N ha−1 per season; 50% mineral fertilizer N plus 50% cattle manure N (50% CM), 50% chicken manure N (50% FC) or 50% pig manure N (50% FP); 75% mineral fertilizer N plus 25% cattle manure N (25% CM), 25% chicken manure N (25% FC) or 25% pig manure N (25% FP). The annual N2O and NO emissions were 2.71 and 0.39 kg N ha−1, respectively, under the Nmin treatment, with an emission factor of 0.50% for N2O and 0.07% for NO. Compared with the Nmin treatment, N2O emissions did not differ when 50% of the mineral N was replaced with manure N (50% CM, 50% FC and 50% FP), while annual NO emissions were significantly reduced by 49.0% and 27.8% under 50% FC and 50% FP, respectively. In contrast, annual N2O emissions decreased by 21–38% compared to the Nmin treatment when 25% of the mineral N was replaced with manure N (25% CM, 25% FC and 25% FP). Most of the reduction occurred during the maize season. The 25% CM, 25% FC and 25% FP treatments had no effect on NO emissions compared to the Nmin treatment. There was no obvious difference in annual N2O and NO emissions among the organic manures at the same application rate, probably due to their similar C/N ratio. Replacing a portion of the mineral fertilizer N with organic fertilizer N did not significantly affect crop grain yield, except for the 50% FC treatment in the wheat season. Overall, the results suggest that the combined application of 25% organic manure N plus 75% mineral fertilizer N had the most potential to mitigate N2O emissions while not affecting crop yield in the maize and wheat rotation system in this area of China. Full article
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15 pages, 1626 KiB  
Article
Acidified Animal Manure Products Combined with a Nitrification Inhibitor Can Serve as a Starter Fertilizer for Maize
by Iria Regueiro, Peter Siebert, Jingna Liu, Dorette Müller-Stöver and Lars Stoumann Jensen
Agronomy 2020, 10(12), 1941; https://doi.org/10.3390/agronomy10121941 - 10 Dec 2020
Cited by 16 | Viewed by 3467
Abstract
There is an urgent need for better management practices regarding livestock farm nutrient imbalances and for finding alternatives to the actual use of mineral fertilizers. Acidification of animal manure is a mitigation practice used to reduce ammonia emissions to the atmospheric environment during [...] Read more.
There is an urgent need for better management practices regarding livestock farm nutrient imbalances and for finding alternatives to the actual use of mineral fertilizers. Acidification of animal manure is a mitigation practice used to reduce ammonia emissions to the atmospheric environment during manure storage and land application. Acidification modifies manure physicochemical characteristics, among which soluble N and P significantly increase. The main objective of this study was to investigate if acidification and the addition of a nitrification inhibitor to manure and placement of the treated manure close to the seed can stimulate maize growth by enhancing nutrient availability, specially P and consequently plant P uptake, at early development stages without the use of mineral N and P as a starter fertilizer. Raw dairy slurry and solid fractions from dairy slurry and digestate from a biogas plant were acidified to pH 5.5 and applied with or without a nitrification inhibitor (DMPP, 3,4-dimethyl pyrazole phosphate) to maize in a pot experiment, where biomass productivity, nutrient uptake and soil P availability were examined. Acidification increased the water-extractable P fraction of all slurry and digestate organic residues (by 20–61% of total P) and consequently plant P uptake from solid fractions of both slurry and digestate compared to the untreated products (by 47–49%). However, higher plant biomass from acidification alone was only achieved for the slurry solid fraction, while the combination of acidification and DMPP also increased plant biomass in the digestate solids treatment (by 49%). We therefore conclude that the combination of acidification and a nitrification inhibitor can increase the starter fertilizer value of slurry and digestate products sufficiently to make them suitable as a maize starter fertilizer. Full article
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17 pages, 2202 KiB  
Article
Long-Term Fertilization Affects Soil Microbiota, Improves Yield and Benefits Soil
by Felix R. Kurzemann, Ulrich Plieger, Maraike Probst, Heide Spiegel, Taru Sandén, Margarita Ros and Heribert Insam
Agronomy 2020, 10(11), 1664; https://doi.org/10.3390/agronomy10111664 - 28 Oct 2020
Cited by 19 | Viewed by 4954
Abstract
Fertilization of soil is needed to fulfill the growing demand for livestock feed and human food requirements. However, fertilization has short and long-term impacts on the soil microbiota. These, in turn, may influence plant viability and growth. We investigated the soil microbiota of [...] Read more.
Fertilization of soil is needed to fulfill the growing demand for livestock feed and human food requirements. However, fertilization has short and long-term impacts on the soil microbiota. These, in turn, may influence plant viability and growth. We investigated the soil microbiota of a 27-year field trial, focusing on the influences of mineral nitrogen (N) fertilization, different composts and combinations of compost plus mineral N as soil amendments. Two N rates (0 and 80 kg per ha) and four different composts (urban organic waste compost (OWC) green waste compost (GC), farmyard manure (MC) compost and sewage sludge compost (SSC)) were used. Soil samples for this study were taken in 2018 after the growing season of maize. In addition to maize yield, the effects on soil physicochemical properties and the soil microbiota were analyzed. There was a trend for increased maize yields for all fertilizers; however, only the application of GC and SSC in combination with mineral N fertilizer showed significant effects. The different organic amendments influenced physicochemical soil properties. Phosphorus concentrations were three times higher in plots receiving SSC (≈312 mg kg−1) and SSC + N (≈297 mg kg−1) than control (≈89 mg kg−1) or mineral N fertilizer (≈97 mg kg−1) alone. Magnesium concentrations in plots treated with SSC (≈74 mg kg−1) were lower compared to soils treated with GC and MC, respectively (≈135 mg kg−1 and 126 mg kg−1). Bacteria exceeded the fungal community in terms of both richness and diversity. While the bacterial community composition differed significantly among the treatments, the fungal community composition was rather unaffected. Our conclusion is that composts produced from various substrates serve as valuable nutrient sources for plants and can partially substitute mineral N. In addition, composts increased soil microbial biomass and modulated the composition of the soil’s microbial community. Full article
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15 pages, 2590 KiB  
Article
Fertigation of Maize with Digestate Using Drip Irrigation and Pivot Systems
by Viviana Guido, Alberto Finzi, Omar Ferrari, Elisabetta Riva, Dolores Quílez, Eva Herrero and Giorgio Provolo
Agronomy 2020, 10(10), 1453; https://doi.org/10.3390/agronomy10101453 - 23 Sep 2020
Cited by 23 | Viewed by 4755
Abstract
Digestate is a nutrient-rich fertilizer and appropriate techniques are required for its application during the maize season to reduce losses and increase the nitrogen use efficiency (NUE). The performance of two different fertigation techniques (drip irrigation and pivot) were assessed using the digestate [...] Read more.
Digestate is a nutrient-rich fertilizer and appropriate techniques are required for its application during the maize season to reduce losses and increase the nitrogen use efficiency (NUE). The performance of two different fertigation techniques (drip irrigation and pivot) were assessed using the digestate liquid fraction. A two-year field test was carried out at two different sites in Lombardy, northern Italy. At each site, fertigation with pivot (P-F, site 1) or drip (D-F, site 2) systems was compared to reference fields where the same irrigation techniques without addition of digestate were used. During the two seasons, the performance of the fertigation systems, amount of fertilizers used, soil nitrogen content, yields, and nitrogen content of the harvested plants were monitored. The digestate application averaged 5 m3/ha per fertigation event with P-F and 4.9 m3/ha with D-F corresponding, respectively, to 28 and 23 kg N/ha. Both irrigation systems were suitable for fertigation provided that the digestate was adequately filtrated. Our results suggest that fertigation with digestate, if properly managed, can be applied during the growing season up to the full amount of nitrogen required by the crop. Full article
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16 pages, 1940 KiB  
Article
Long-Term Effect of Manure and Mineral Fertilizer Application Rate on Maize Yield and Accumulated Nutrients Use Efficiencies in North China Plain
by Fan Fan, Hongyan Zhang, Gabriela Alandia, Laichao Luo, Zhenling Cui, Xinsheng Niu, Ruili Liu, Xiaoning Zhang, Yu Zhang and Fusuo Zhang
Agronomy 2020, 10(9), 1329; https://doi.org/10.3390/agronomy10091329 - 4 Sep 2020
Cited by 7 | Viewed by 3331
Abstract
Overuse of mineral fertilizer has become common at the North China Plain. Simultaneously, more organic manure resources are available for smallholder farmers. In order to increase the use of organic manure and reduce mineral fertilizer applications, a 10-year fertilization experiment with maize took [...] Read more.
Overuse of mineral fertilizer has become common at the North China Plain. Simultaneously, more organic manure resources are available for smallholder farmers. In order to increase the use of organic manure and reduce mineral fertilizer applications, a 10-year fertilization experiment with maize took place between 2008 and 2017. We assessed the long-term effects of cattle manure (CM) application and a complete nutrient substitution with mineral fertilizer (MF) at four application levels (3, 6, 9 and 12 t ha−1 CM) on yield, macronutrients (N, P and K) use efficiencies and soil conditions. Results showed that maize yields from CM and MF treatments differed across time and were significantly different in the first year of the experiment to no significant differences with increasing experimental time. In addition, increased MF levels did not result in increased maize yields; this response was different with CM applications. The highest 10-year maize average yield was 7.7 t ha−1 obtained with 9 t ha−1 of CM. Our results also showed that at the lowest application level (3 t ha−1 CM), the partial factor productivity (PFP) and the agronomic efficiency (AE) of all macronutrients were significantly higher with MF than with CM applications. Nevertheless, these differences narrowed with increased fertilizer input levels. The MF and CM recovery efficiency (RE) of N, P and K performed differently. Generally, MF exhibited significantly higher N-RE than CM treatments. CM treatments had significantly higher P-RE, but no K-RE differences were found between CM and MF. Soil available N, P and K significantly increased when fertilizer levels raised. MF treatments exhibited similar levels of soil available N, but lower soil available P and K compared with CM treatments. Full article
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23 pages, 1280 KiB  
Article
Effect of Nitrification Inhibitors on N2O Emissions after Cattle Slurry Application
by Christina Herr, Thomas Mannheim, Torsten Müller and Reiner Ruser
Agronomy 2020, 10(8), 1174; https://doi.org/10.3390/agronomy10081174 - 11 Aug 2020
Cited by 20 | Viewed by 3693
Abstract
Cattle slurry injection (INJ) has shown to be an efficient measure to reduce ammonia (NH3) losses from soils but it might also significantly increase nitrous oxide (N2O) emissions, which can dominate the total greenhouse gas (GHG) release in silage [...] Read more.
Cattle slurry injection (INJ) has shown to be an efficient measure to reduce ammonia (NH3) losses from soils but it might also significantly increase nitrous oxide (N2O) emissions, which can dominate the total greenhouse gas (GHG) release in silage maize production (Zea mays L.). Nitrification inhibitors (NIs) are known for their potential to mitigate N2O. Therefore, we tested the effect of NIs added to cattle slurry before INJ on N2O fluxes from a Haplic Luvisol under silage maize in southwest Germany. We determined N2O fluxes at least weekly, with the closed chamber method over two full years. NIs differ in their chemical and physical behavior and we therefore tested a range of commercially available NIs: 3,4-dimethylpyrazole phosphate, 3,4-dimethylpyrazol succinic acid, a mixture of both, nitrapyrin, dicyandiamide, and 1,2,4 triazol and 3-methylpyrazol. Although not significant, INJ treatments with NI showed lower mean annual N2O emissions than the INJ treatment without NI in the 1st year. The emission reduction by NI of 46% in the 2nd year was statistically significant. In both years, we did not find any difference in N2O release, crop yield, or nitrogen removal between the different NI treatments. In the 1st year, which was extraordinary dry and warm, emission factors (EFs) for all INJ treatments were 4 to 8-fold higher than default EF from the IPCC. Even in the 2nd year, only three NI treatments reached EFs within the range provided by the IPCC. Direct N2O accounted for between 81 and 91% of the total GHG emission. Area- and yield-related GHG emission of the broadcast application with subsequent incorporation was in both years in the statistical class with lowest emission. In contrast, INJ with NIs showed similar GHG emissions in only one year, and consequently, incorporation was found to be the optimum management practice for livestock farmers in our study region. Full article
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14 pages, 2110 KiB  
Article
Substitution of Mineral Fertilizer with Organic Fertilizer in Maize Systems: A Meta-Analysis of Reduced Nitrogen and Carbon Emissions
by Zhibiao Wei, Hao Ying, Xiaowei Guo, Minghao Zhuang, Zhenling Cui and Fusuo Zhang
Agronomy 2020, 10(8), 1149; https://doi.org/10.3390/agronomy10081149 - 6 Aug 2020
Cited by 49 | Viewed by 7688
Abstract
Organic fertilizer is an effective substitute for mineral fertilizer that improves crop yield and is environmentally friendly. However, the effects of substitution often vary due to complicated interactions among the organic fertilizer substitution rate (Rs), total nutrient supply, and type of cropping system [...] Read more.
Organic fertilizer is an effective substitute for mineral fertilizer that improves crop yield and is environmentally friendly. However, the effects of substitution often vary due to complicated interactions among the organic fertilizer substitution rate (Rs), total nutrient supply, and type of cropping system used. We performed a meta-analysis of 133 maize studies, conducted worldwide, to assess maize yield and environmental performance with substitution of mineral fertilizer with organic fertilizer. At an equivalent nitrogen (N) rate, substituting mineral fertilizer with organic fertilizer increased maize yield by 4.22%, reduced NH3 volatilization by 64.8%, reduced N leaching and runoff by 26.9%, and increased CO2 emissions by 26.8%; however, it had no significant effect on N2O or CH4 emissions. Moreover, substitution with organic fertilizer increased the soil organic carbon sequestration rate by 925 kg C ha−1 yr−1 and decreased the global warming potential by 116 kg CO2 eq ha−1 compared with mineral fertilizer treatment. The net global warming potential after organic fertilizer substitution was −3507 kg CO2 eq ha−1, indicating a net carbon sink. Furthermore, the effect of organic fertilizer substitution varied with the fertilization rate, Rs, and treatment duration. Maize yield and nitrogen use efficiency tended to increase with increasing N application rate following substitution of mineral fertilizer with organic fertilizer. Full substitution reduced N losses more than partial substitution. Further analysis revealed that the yield-optimal Rs for organic N in maize production was 40–60%. Moreover, maize yield and nitrogen use efficiency were further increased after long-term (≥ 3 years) combined use of organic and mineral fertilizers. These findings suggest that rational use of organic and mineral fertilizers improves maize productivity, increases soil organic carbon sequestration, and reduces N and C losses. Full article
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14 pages, 1326 KiB  
Article
Integrated Soil–Crop System Management with Organic Fertilizer Achieves Sustainable High Maize Yield and Nitrogen Use Efficiency in Northeast China Based on an 11-Year Field Study
by Yin Wang, Yaqi Cao, Guozhong Feng, Xiaoyu Li, Lin Zhu, Shuoran Liu, Jeffrey A. Coulter and Qiang Gao
Agronomy 2020, 10(8), 1078; https://doi.org/10.3390/agronomy10081078 - 26 Jul 2020
Cited by 9 | Viewed by 2938
Abstract
To increase crop productivity while reducing environmental costs, an integrated soil–crop system management (ISSM) strategy was developed and successfully adopted in China. However, little information is available on the long-term ISSM effects on maize agronomic and environmental performance. Therefore, we evaluated the effects [...] Read more.
To increase crop productivity while reducing environmental costs, an integrated soil–crop system management (ISSM) strategy was developed and successfully adopted in China. However, little information is available on the long-term ISSM effects on maize agronomic and environmental performance. Therefore, we evaluated the effects of ISSM with combining inorganic and organic fertilizers on maize productivity, N use efficiency (NUE) and N balance and losses as compared with farmers’ practice (FP) and high-yielding practice (HY), based on an 11-year field experiment in Northeast China. Maize yield in ISSM (11.7–14.3 Mg ha−1) achieved 97.7% of that in HY and was increased by 27% relative to FP. The excellent yield performance in ISSM was mainly attributed to optimum plant population structure and yield components. Annual N surplus in ISSM was only 7 kg ha−1, which was considerably lower than that in FP (52 kg ha−1) and HY (109 kg ha−1). Consequently, ISSM obtained significantly lower N losses and greenhouse gases emissions and higher NUE. In contrast to FP, crop performance in ISSM showing better sustainability and inter-annual stability. In conclusion, ISSM is an effective strategy to achieve long-term sustainable high crop yields and NUE with less environmental costs in the intensive agricultural system. Full article
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Review

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19 pages, 1425 KiB  
Review
Optimization of the Nutrient Management of Silage Maize Cropping Systems in The Netherlands: A Review
by Gerard Velthof, Herman van Schooten and Wim van Dijk
Agronomy 2020, 10(12), 1861; https://doi.org/10.3390/agronomy10121861 - 26 Nov 2020
Cited by 5 | Viewed by 3053
Abstract
Silage maize is, after grassland, the second largest crop in the Netherlands. The amounts of nutrients applied to silage maize have greatly decreased since the 1980s because of the implementation of a series of environmental policies. The aim of this review paper was [...] Read more.
Silage maize is, after grassland, the second largest crop in the Netherlands. The amounts of nutrients applied to silage maize have greatly decreased since the 1980s because of the implementation of a series of environmental policies. The aim of this review paper was to provide an overview of the nutrient management of and losses from silage maize cropping systems in the Netherlands during recent decades based on a literature review and a time series of nitrogen (N) and phosphorus (P) uses, yields, surpluses, and losses. The total N input as slurry to silage maize on sandy soils decreased from up to 500 kg N/ha in 1985 to approximately 180 kg N/ha in recent years. This decrease was due to the implementation of legislation with maximum permissible P application rates in the 1980s and 1990s, maximum permissible N and P losses in the 1997–2005 period, and of maximum permissible N and P application rates from 2006 onwards. Implementation of low ammonia (NH3) emission application techniques of manure in the early 1990s greatly reduced NH3 emission. The relative decrease of N losses from silage maize on sandy soils in the 1995–2018 period was 70% for nitrate (NO3) leaching, 97% for NH3 emissions, 65% for nitrogen oxide (NO) emissions, and 32% for nitrous oxide (N2O) emissions. The P surplus on the soil balance of silage maize decreased from approximately 150 kg P2O5/ha in the 1980s to less than 10 kg P2O5/ha in recent years, showing that P inputs and outputs are currently coming close to a zero balance in silage maize cropping systems. Although the emissions from silage maize cultivation have greatly decreased, further improvements in nutrient management are needed. The water quality standards have still not been met and there are new challenges related to the mitigation of emissions of ammonia and greenhouse gases. Full article
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