Energy efficiency of field crops depending on the nitrogen fertilization based on IOSDV long-term field experiment and opportunities.

Transcription

1 Energy efficiency of field crops depending on the nitrogen fertilization based on IOSDV long-term field experiment and opportunities of IOSDV field experiment for energy analysis Helis Rossner Alar Astover

2 IOSDV(Der Internationale Organische Stickstoffdauerdüngungversuch) IOSDV was established 1956 as a co-operation network under International Union of Soil Sciencesoil-fertility working-group. 22 field experiments in 11 European countries The main idea: study the yield response to the nitrogen fertilization changes in soil condition

3 IOSDV in Estonia IOSDV Tartu field experiment ineerikaexperimental station is established in 1989(prof. emer. Paul Kuldkepp) Crop rotation: spring wheat spring barley potato Soil: sandyloam Fragi- Stagnic- Albeluvisol by WRB ca 5,9 % Estonian soils (ca 70 % of those are arable (Kokk, 1995)

4 Factors Organic fertilisers 1 -Without organic fert. 2 -Farmyard manure -40 t/ha for potato 3 -Alternative organic fertilisers (beet leaves, straw, recultivation substance from oil shale semi-coke, red clover, residual from biogas and paper pulp production) Mineral fertilisers N rates 0, 40, 80, 120, 160 kg/ha Field I Field II Field III

5 Nitrogen crop response curves Quadratic equation (polynom) -Y=a0+a1x±a2x 2 Optimization nitrogen fert - Nopt=a1 /2a2x agronomic, economic, energy. t/ha 5 4,5 4 3,5 Spring wheat yield response to mineral N y = -0,00010x 2 + 0,02669x + 2,00397 R² = 0,98979 Max profit Max yield 3 2,5 2 Max energy ratio Yield, t/ha 1,5 NKT Necon. Nagr N kg/ha

6 Energy parameters ENERGY GAIN(ES) OUTPUT - INPUT ENERGY RATIO(KT) OUTPUT/INPUT COMPLEX INDEX Relative importance of every single plot compared to the best plot value was found for ES and KT and then summarized. Combines energy ratio and energy gain (max value=2)

7 Method of energy balancing -Hülsbergen et al. (2001)

8 Energy equivalents Energy Unit equivalent Reference Diesel MJ kg -1 39,6 Reinhardt (1993) Fertilizers N (min. fert.) MJ kg -1 35,3 Appl (1997) (32,2-45) N (org. fert.) 0,43*Nmin Schilling(1987) P (min. org. fert.) MJ kg -1 36,2 Kaltschmitt ja Reinhardt (1997) K (min. org. fert.) MJ kg -1 11,2 Kaltschmitt ja Reinhardt (1997) Plant protection agents Green (1987) Herbicides MJ kg Fungicides MJ kg Insecticides MJ kg Seed Kalk et al.(1995) Spring wheat MJ kg -1 5,5 Spring barley MJ kg -1 5,5 Potato MJ kg -1 1,3 Machinery MJ kg Kalk, Hülsbergen (1996) Transport MJ t -1 km -1 6,03 Müller (1989)

9 Results

10 Energy inputfor cereals

11 Energy inputfor potato GJ/ha - without organic fert; + manure 40 t/ha Transport Machinery Plant protection NPK* Seed Potatoe+ Potatoe+ Potatoe+ Potatoe+ Potatoe- Potatoe- Potatoe- Potatoe- Potatoe- Potatoe+ Diesel N kg/ha

12 Spring wheat energy yield, GJ/ha GJ/ha without organic fert. GJ/ha manure first year aftereffect 120 Vertical lines - U95% Straw, GJ/ha Grain, GJ/ha Straw, GJ/ha Grain, GJ/ha kg N/ha N kg/ha

13 Barley energy yield, GJ/ha GJ/ha 100 without org. fert GJ/ha 100 manure second year aftereffect Straw, GJ/ha Grain, GJ/ha Straw, GJ/ha Grain, GJ/ha N kg/ha kg N ha

14 Potato energy yield, GJ/ha GJ/ha 120 without organic fertilizers manure 40 t/ha kg N/ha

15 Energy gain (output-input) GJ/ha Spring wheat grain - Spring wheat grain+straw N kg/ha GJ/ha Barley grain - Barley grain+straw N kg/ha Grain+straw higher energy gain values Considering grain energy gain is similar for both cereals (different on low N rates) Optimal N rates depend on crop Nopt similar to Nagr

16 Energy ratio (output/input) KT Spring wheat grain - Spring wheat grain+straw N kg/ha KT Barley - Barley (grain+straw) N kg/ha Lower for barley differences decreased with N rate increase. Straw increased the energy ratio, more for wheat. Lower Nopt norms than for optimizing energy gain.

17 ESvs KT ES-GJ/ha ,4 Wheat 54 GJ/ha KT N kg/ha Energy gain (ES)- Energy ratio (KT)- Max net energy yield (energy gain) vs min pressure to the environment (energy ratio)

18 Energy gain, energy ratio COMPLEX INDEX Wheat KT; ES-GJ/ha Koond 60 9, GJ/ha Energy gain (ES) Energy ratio (KT) Complex index 3 (Koond)- 10 1, N kg/ha

19 Optimum N rate, kg/ha Spring wheat (+ by-products) Barley (+ by-products) Agronomy Energy gain (ES) Energy ratio (KT) COMPLEX INDEX (Koond)

20 Effect of manure Energy ratio calculated at optimum N rate Energy ratio (KT) Without organic fert. Manure Crop rotation (potato-spring wheat-barley) 10,2 8,4

21 Conclusion Results depend on used methodics. They are specific to the experimental site (soil conditions and used agrotechnology). Energy parameters depend on crop. For cereals better energy parameters were gained using mineral fertilizers on the backround of organic! New complex index fertilizers recomendations consider both important characteristics -maximizing net energy yield and minimizing pollution to the environment!

22 Further opportunities of IOSDV field experiment for energy analysis

23 Soil fertility and productivity In some cases energy ratio is the highest at low-input crop production practices But problems can arise with Soil quality and fertility (how to estimate?) Long-term productivity (yield level) Yield quality Only long-term trends are meaningful! Work Package Upkeeping the production capacity of fields

24 Organic fertilizers

25 Mineral fertilizers

26 Annual change rate (%) in grain yield over 18 years % per year Spring wheat 2,5 2,0 1,5 1,0 0,5 0,0-0,5-1,0-1,5-2,0 Without organic fertilizers Manure first year aftereffect N0 N40 N80 N120 N160

27 Annual change rate (%) in grain yield over 18 years % per year Barley 3,0 2,5 2,0 1,5 1,0 0,5 0,0-0,5-1,0-1,5-2,0 Without organic fertilizers Manure second year after-effect N0 N40 N80 N120 N160

28 Trends in barley yield (rotation without organic fertilisers) t/ha +4% % I...II rotation V...VI rotation 0.0 N0 N120

29 Annual change rate (%) in potato yield over 18 years % per year Potato 3,5 3,0 2,5 2,0 1,5 1,0 0,5 0,0-0,5-1,0 Without organic fertilizers Manure 40 t/ha N0 N40 N80 N120 N160

30 Alternative fertilizers Beet leaves + straw Recultivation substance from oil shale semicoke Biogas digestate Aspen pulp mill waste

31 Potato yield in t/ha a, b, c a, b, c a, b, c a, b, c Org. väetiste variandid ilma sõnnik alternatiivne 20 a, c a 15 Solid biogas digestate (pig slurry) 10 a, b, c 10, 15 or 20 t/ha 5 0 N0 N40 N80 N120 N160 MKL 10 MKL 15 MKL 20 Equal effect compared with traditional dairy manure (ca 40 t/ha) to the yield Energy analysis is still missing

32 Barley yield in t/ha without org fert 4 manure after-effect pulp mill after-effect N0 N40 N80 N120 N160 Control pulp mill 40 t pulp mill + clinker dust 20 t pulp mill + clinker dust 40 t

33 Other examples

34 Probability of energy ratio for rye (blue line in graph) ENPOS Plant Production seminar

35 Astover et al. 2006

36 Need for improved methods Energy input for organic fertilizers Usually equal based on nutrient contents with mineral fertilizers but what could be alternative approach? Other inputs that should be considered grain drying etc. Energy eqvivalents for complex fertilizers?

37 Econometric methods efficiency Applicable also for energy analysis but still rarely used The non-parametric method Data Envelopment Analysis (DEA) DEA uses mathematical programming to produce a linear best practice frontier over the data and then calculates efficiency measures relative to this frontier. The objective of DEA is to determine the relative efficiency of each farm (decision unit).

38 Farm energy efficiency, DEA approach Chauhan et al. 2006

39 Farm energy efficiency, DEA approach Chauhan et al. 2006

40 Thank You for Attention!