Nitrogen Surplus—A Unified Indicator for Water Pollution in Europe?
Abstract
:1. Introduction
1.1. Nitrogen Budgets and Relation to Water Quality
1.2. Nitrogen Surpluses as a Result of Budgets and as Indicators for Measures and Policies
1.3. Nitrogen Budgets for Investigating Farm Performance and as Tool for Farm Advice
2. Materials and Methods
2.1. Theoretical Framework
2.1.1. Budget Type
2.1.2. Level of Application of Budget
2.2. Survey on Nitrogen Budgets at the Farm Level
- The type and elements of fertilization plans and budgets used at the farm and plot levels,
- The type and elements of budgets used at the regional or national levels,
- The legally binding procedures in connection with the use of fertilization plans and budgets,
- The informative value of budgets, according to budget type, and
- The barriers in the use/implementation of budgets according to the individual experience and the experience in the FAIRWAY case studies.
3. Results
3.1. Prevalence of Fertilization Planning and Budgeting at the Farm Level
3.2. Results on Fertilization Planning
3.2.1. Factors Considered in Fertilization Planning
3.2.2. Impact of Technical Progress on Nitrogen Requirement of Crop
3.2.3. Factors Used to Estimate Plant-Available Nitrogen in Manure and Other Organic Fertilizers
3.2.4. Emission Factors for Nitrogen
3.2.5. The Plant Availability of Nitrogen in Manure
3.3. Elements of Soil Surface Budgets
3.4. Elements of Farm Budgets
3.5. Comparison of Budgets in Different Countries
3.5.1. Germany
3.5.2. Switzerland
3.5.3. The Netherlands
- A farm with a high individual herd NUE produces less N in manure, and thus reduces the need for N-export;
- A farm with a high individual herd NUE consumes less feedstuff;
- A high NUE with respect to soil indicates a low farm N surplus;
- A high NUE of grassland indicates a high N yield;
- A high N input goes along with a lower NUE;
- A high NUE, in turn, results in substantial savings for the farmer (expenses for fertilizer, feedstuff and for manure export) [46].
3.5.4. Romania
4. Discussion
4.1. Prevalence of N Fertilization Planning and N Budgeting at the Farm Level
4.2. Need for the Standardization of Data Collection
4.2.1. Nitrogen Concentration in Different Manure Types
4.2.2. Analyses and Measurements versus Standard Data and Estimations
4.3. Detection of “Hidden” Surpluses Using N Budgets
4.3.1. Nitrogen Losses during Housing and Storage and during/after Manure Application
4.3.2. The Plant Availability of Nitrogen in Organic Fertilizers and Soil Conditioners
4.4. Evaluation of the Presented Budget Types
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Conflicts of Interest
References
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Country | Fertilization Plan (y/n) | Legally Bound (y/n) | N Budgets (y/n) | Legally Bound (y/n) |
---|---|---|---|---|
B (Flan) | (y) | (y)(1) | (y) | (y)(2) |
CH | (y) | (y)(3) | y | y |
DK | y | y | N(4) | - |
FR | y | (y)(5) | n | - |
GE | y | y | y | y |
NL | y | (y)(6) | y | n |
PT | (y) | (y)(5) | n | - |
IE | y | (y)(7) | n | - |
RO | y | y | y | y |
Sl | y | y | (y)(8) | - |
UK-NI | y | y | n | - |
N emissions From Stables and Storages | Availability of Applied N in Soil for Crops | N Emissions during/after Organic Fertilizer Application | ||
---|---|---|---|---|
% of N excretion | % of applied N | % of N excretion | % of applied N | |
B (Flan)(1) | y | y | n | n |
CH | y | y | n | n |
DK | y(4) | y(3,4) | n | n |
FR | n | n.a.(2) | n | n |
GE | y | y | y(5) | y(6) |
IE | n | y | n | n |
NL | y | y | n(7) | y(8) |
PT | n | y | n | y |
RO | y | y | y | n |
Sl | y | y | n | y |
UK-NI | n | y | n | n |
Crop Available % of Total Nitrogen (=Manure N Efficiency) | ||||||||
---|---|---|---|---|---|---|---|---|
Cattle | Pigs | Layer | Broiler | Sheep | ||||
Country | Slurry | Solid | Slurry | Solid | Slurry | Solid | ||
AT | 50 | 5/15 | 65 | 5/15 | 60 | 30 | 30 | |
B(Flan) | 60 60 | 60 30 | 60 60 | 30 30 | 60 60 | 30 30 | 30 30 | 30 30 |
BG | 20–35 | 20 | 40–45 | 20 | 40–50 | 40–50 | 40–50 | |
CH(1) | 45 | 20 | 50 | 35 | 35 | 35 | 30 | |
CZ | 60 | 40 | 60 | 40 | 60 | 40 | 40 | 40 |
DK(2) | 70 | 65 | 75 | 65 | 70 | 65 | 65 | 65 |
EE | 50 | 25 | 50 | 25 | 50 | 25 | 25 | 25 |
GE(2) | 50 60 | 25 35 | 60 70 | 30/40 40 | 60 70 | 60 70 | 25 35 | |
FR | 45 | 10/15 | 60 | 20/30 | 45 | 45 | 35 | 10 |
GR | 20–35 | 10 | 20–45 | 10 | 20–30 | 20–30 | 20–30 | 10 |
IE | 40 | 30 40 | 50 | 50 50 | 50 | 50 50 | 50 50 | 30 40 |
IT(3) | 24–62 | 24–62 | 28–73 | 28–73 | 32–84 | 32–84 | 32–84 | |
LV | 50 | 25 | 50 | 25 | 30 | 25 | 25 | |
LT | 35 | 35 | 35 | |||||
LU | 25–50 | 30–50 | 30–60 | 30–50 | 50 | 50 | ||
NL | 60/40 | 40/25 | 60–70 | 55 | 60/70 | 55 | 55 | |
PL | 50–60 | 30 | 50–60 | 30 | 50–60 | 30 | 30 | 30 |
PT | 55–75 60 | 30–60 20 | 50–80 80 | 40–60 | 50–70 | 40–60 90 | 40–60 90 | 40–60 |
RO | 50 | 30 | 50 | 30 | 30 | 50 | ||
SE | 40–50 | 36–41 | 57 | 47 | 48 | 47/57 | ||
SI | 50 75–85 | 30 50–70 | 50 75–85 | 30 50–70 | 30 75–85 | 50 50–70 | 50/ 50–70 | |
SK | 50 | 30 | 50 | 30 | 30 | 50 | 50 | |
UK | 20/35 | 10 | 25/50 | 10 | 20/35 | 20/30 | 10 | |
UK-NI | 38 | 30 30 | 50 50 | 30 | 30 30 | 30 |
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Klages, S.; Heidecke, C.; Osterburg, B.; Bailey, J.; Calciu, I.; Casey, C.; Dalgaard, T.; Frick, H.; Glavan, M.; D’Haene, K.; et al. Nitrogen Surplus—A Unified Indicator for Water Pollution in Europe? Water 2020, 12, 1197. https://doi.org/10.3390/w12041197
Klages S, Heidecke C, Osterburg B, Bailey J, Calciu I, Casey C, Dalgaard T, Frick H, Glavan M, D’Haene K, et al. Nitrogen Surplus—A Unified Indicator for Water Pollution in Europe? Water. 2020; 12(4):1197. https://doi.org/10.3390/w12041197
Chicago/Turabian StyleKlages, Susanne, Claudia Heidecke, Bernhard Osterburg, John Bailey, Irina Calciu, Clare Casey, Tommy Dalgaard, Hanna Frick, Matjaž Glavan, Karoline D’Haene, and et al. 2020. "Nitrogen Surplus—A Unified Indicator for Water Pollution in Europe?" Water 12, no. 4: 1197. https://doi.org/10.3390/w12041197
APA StyleKlages, S., Heidecke, C., Osterburg, B., Bailey, J., Calciu, I., Casey, C., Dalgaard, T., Frick, H., Glavan, M., D’Haene, K., Hofman, G., Leitão, I. A., Surdyk, N., Verloop, K., & Velthof, G. (2020). Nitrogen Surplus—A Unified Indicator for Water Pollution in Europe? Water, 12(4), 1197. https://doi.org/10.3390/w12041197