Crop rotation implications in water balance through land use change scenarios using SWAT model David Rivas-Tabares, Ana María Tarquis, Bárbara Willaarts, Ángel de Miguel September 21 th, 2018
Outline I. Case Study II. Crop rotation strategy (SWAT model set-up) III. Model application IV. Model results V. Discussion VI. Conclusions
Flow gauge Case study
Land use maps Stakeholders Mapping activity Cega-Eresma-Adaja LSH LBA LSP 4
Land use dynamics (HRU level) HRUs Land Use Distribution LSP 41% 3.5% 24% 19% 12.6% LBA 57% 4.4%7.3% 19% 12.6% LSH 33% 2.6% 2.6% 19% 12.6% BASE 58% 2.6%8% 19% 12.6% 0% 20% 40% 60% 80% 100% RAINFED IRRI FALLOW GRASSLAND AND SHRUBS FOREST URBAN WATER
HRUs Selection (simplification) TOTAL HRUs (224) STATIC HRUs (203) 1). 0-5 ha (111) 2). 5-100 ha (80) 3). Fixed HRUs (12) DYNAMIC HRUs 41% >100ha (21) 59% 1% 9% 31% Urban/ transport.(4) 12% 69% 1). Barley (6) 2). Wheat (5) 3). Grassland & Shrubs (4) 4). Sunflower (2) 30% 13% 8% 7% Actual Forest (6) 18% 5). Other Cereals (2) 2% Actual Horticulture(2) 1% 6). Hay (1) 7). Vineyard (1) 0.5% 0.4%
Baseline Crop Rotation Simplified schema 1 14% 16 HRUs ( 12,448 ha) Aggregated Pattern Type Year 1 Year 2 Year 3 Year 4 Year 5 1 Cereal/Forrage Cereal/Forrage Barley Sunflower Barley 2 Barley Sunflower Wheat Barley/ Other Cereal Barley/ Other Cereal 3 Other Cereals Legumes Sunflower Wheat Barley 4 Sunflower Barley Sunflower Cereal Cereal 5 Cereal Cereal Other cereal Sunflower/Legumes Sunflower/Legumes Monocrop Barley Wheat Barley Wheat Barley Cereals: Barley and wheat Monocrop 25% HRU 2004_2005* 2005_2006* 2006_2007* 2007_2008* 2008_2009* 2009_2010* 2010_2011* 2011_2012* 2012_2013* 2013_2014* 1 AGRC PEAS SUNF WWHT BARL AGRC PEAS SUNF WWHT BARL 2 BARL SUNF WWHT AGRC AGRC BARL SUNF WWHT AGRC AGRC 3 HAY BARL BARL SUNF BARL HAY BARL BARL SUNF BARL 4 SUNF BARL SUNF WWHT BARL SUNF BARL SUNF WWHT BARL 5 WWHT BARL AGRC PEAS BARL WWHT BARL AGRC PEAS BARL 6 AGRC PEAS SUNF WWHT BARL AGRC PEAS SUNF WWHT BARL 7 BARL SUNF WWHT BARL BARL BARL SUNF WWHT BARL BARL 8 SUNF BARL WWHT SUNF BARL SUNF BARL WWHT SUNF BARL 9 WWHT BARL BARL WWHT SUNF WWHT BARL BARL WWHT SUNF 10 BARL AGRC SUNF WWHT PEAS BARL AGRC SUNF WWHT PEAS 11 WWHT BARL BARL SUNF BARL WWHT BARL BARL SUNF BARL 12 BARL WWHT BARL BARL WWHT BARL WWHT BARL BARL WWHT 13 WWHT WWHT SUNF WWHT BARL WWHT WWHT SUNF WWHT BARL 14 BARL BARL AGRC PEAS SUNF BARL BARL AGRC PEAS SUNF 15 WWHT AGRC PEAS WWHT SUNF WWHT AGRC PEAS WWHT SUNF 16 BARL HAY BARL AGRC SUNF BARL HAY BARL AGRC SUNF 5 20% 4 13% 3 4% 2 24%
Scenarios LU Reference Maps 224 HRUs 224 HRUs 224 HRUs 224 HRUs
Hydrological years Rotation scheme template Sept 5 1 Jul 4 2 3 Apr
HRU 1 Baseline Crop Rotation Timeline Schema 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 AGRC PEAS SUNF WWHT BARL AGRC PEAS SUNF WWHT BARL BARL SUNF WWHT AGRC AGRC BARL SUNF WWHT AGRC AGRC HAY BARL BARL SUNF BARL HAY BARL BARL SUNF BARL SUNF BARL SUNF WWHT BARL SUNF BARL SUNF WWHT BARL WWHT BARL AGRC PEAS BARL WWHT BARL AGRC PEAS BARL AGRC PEAS SUNF WWHT BARL AGRC PEAS SUNF WWHT BARL BARL SUNF WWHT BARL BARL BARL SUNF WWHT BARL BARL SUNF BARL WWHT SUNF BARL SUNF BARL WWHT SUNF BARL WWHT BARL BARL WWHT SUNF WWHT BARL BARL WWHT SUNF BARL AGRC SUNF WWHT PEAS BARL AGRC SUNF WWHT PEAS WWHT BARL BARL SUNF BARL WWHT BARL BARL SUNF BARL BARL WWHT BARL BARL WWHT BARL WWHT BARL BARL WWHT WWHT WWHT SUNF WWHT BARL WWHT WWHT SUNF WWHT BARL BARL BARL AGRC PEAS SUNF BARL BARL AGRC PEAS SUNF WWHT AGRC PEAS WWHT SUNF WWHT AGRC PEAS WWHT SUNF BARL HAY BARL AGRC SUNF BARL HAY BARL AGRC SUNF
LSH Crop Rotation Schema LSH HRU area distribution [%] LU(baseline) 1 2 3 4 5 6 Area [ha] AGRC 2 5 496 BARL RNGE RNGE RNGE RNGE RNGE RNGE 7174 HAY RNGE 118 SUNF 1 RNGE 1591 WWHT 12 13 14 15 16 3070 Total 12448 HRU 2004_2005* 2005_2006* 2006_2007* 2007_2008* 2008_2009* 2009_2010* 2010_2011* 2011_2012* 2012_2013* 2013_2014* 1 BARL SUNF WWHT AGRC AGRC BARL SUNF WWHT AGRC AGRC 2 WWHT BARL AGRC PEAS BARL WWHT BARL AGRC PEAS BARL 3 RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE 4 RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE 5 RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE 6 RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE 7 RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE 8 RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE 9 RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE 10 AGRC PEAS SUNF WWHT BARL AGRC PEAS SUNF WWHT BARL 11 RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE 12 BARL WWHT BARL BARL WWHT BARL WWHT BARL BARL WWHT 13 WWHT WWHT SUNF WWHT BARL WWHT WWHT SUNF WWHT BARL 14 BARL BARL AGRC PEAS SUNF BARL BARL AGRC PEAS SUNF 15 WWHT AGRC PEAS WWHT SUNF WWHT AGRC PEAS WWHT SUNF 16 BARL HAY BARL AGRC SUNF BARL HAY BARL AGRC SUNF
LBA Crop Rotation Schema LSH HRU area distribution [%] LU(baseline) 1 2 3 4 5 6 Area [ha] AGRC 2 3 496 BARL 9 7 9 7 HORT 7 7174 HAY WWHI 118 SUNF 8 8 1591 WWHT 12 13 14 15 16 3070 Total 12448 HRU 2004_2005* 2005_2006* 2006_2007* 2007_2008* 2008_2009* 2009_2010* 2010_2011* 2011_2012* 2012_2013* 2013_2014* 1 BARL SUNF WWHT AGRC AGRC BARL SUNF WWHT AGRC AGRC 2 HAY BARL BARL SUNF BARL HAY BARL BARL SUNF BARL 3 WWHT BARL BARL WWHT SUNF WWHT BARL BARL WWHT SUNF 4 BARL SUNF WWHT BARL BARL BARL SUNF WWHT BARL BARL 5 WWHT BARL BARL WWHT SUNF WWHT BARL BARL WWHT SUNF 6 BARL SUNF WWHT BARL BARL BARL SUNF WWHT BARL BARL 7 HORT HORT HORT HORT HORT HORT HORT HORT HORT HORT 8 BARL SUNF WWHT BARL BARL BARL SUNF WWHT BARL BARL 9 WWHI BARI BARI WWHI BARI WWHI BARI BARI WWHI BARI 10 SUNF BARL WWHT SUNF BARL SUNF BARL WWHT SUNF BARL 11 SUNF BARL WWHT SUNF BARL SUNF BARL WWHT SUNF BARL 12 BARL WWHT BARL BARL WWHT BARL WWHT BARL BARL WWHT 13 WWHT WWHT SUNF WWHT BARL WWHT WWHT SUNF WWHT BARL 14 BARL BARL AGRC PEAS SUNF BARL BARL AGRC PEAS SUNF 15 WWHT AGRC PEAS WWHT SUNF WWHT AGRC PEAS WWHT SUNF 16 BARL HAY BARL AGRC SUNF BARL HAY BARL AGRC SUNF
LSP Crop Rotation Schema LSH HRU area distribution [%] LU(baseline) 1 2 3 4 5 6 Area [ha] AGRC RNGE RNGE 496 BARL 7 RNGE 7 7 7 7 7174 HAY HORT 118 SUNF 8 RNGE 1591 WWHT 12 13 14 15 16 3070 Total 12448 HRU 2004_2005* 2005_2006* 2006_2007* 2007_2008* 2008_2009* 2009_2010* 2010_2011* 2011_2012* 2012_2013* 2013_2014* 1 RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE 2 RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE 3 BARL SUNF WWHT BARL BARL BARL SUNF WWHT BARL BARL 4 RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE 5 BARL SUNF WWHT BARL BARL BARL SUNF WWHT BARL BARL 6 BARL SUNF WWHT BARL BARL BARL SUNF WWHT BARL BARL 7 BARL SUNF WWHT BARL BARL BARL SUNF WWHT BARL BARL 8 BARL SUNF WWHT BARL BARL BARL SUNF WWHT BARL BARL 9 HORT HORT HORT HORT HORT HORT HORT HORT HORT HORT 10 SUNF BARL WWHT SUNF BARL SUNF BARL WWHT SUNF BARL 11 RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE RNGE 12 BARL WWHT BARL BARL WWHT BARL WWHT BARL BARL WWHT 13 WWHT WWHT SUNF WWHT BARL WWHT WWHT SUNF WWHT BARL 14 BARL BARL AGRC PEAS SUNF BARL BARL AGRC PEAS SUNF 15 WWHT AGRC PEAS WWHT SUNF WWHT AGRC PEAS WWHT SUNF 16 BARL HAY BARL AGRC SUNF BARL HAY BARL AGRC SUNF
Calibration Process Calibration Daily time step Flow Yield Yearly Barley Wheat 1. CN2 2. Alpha_BF 3. GW_DELAY 4. GWQMN 5. SOL_AWC 6. SOL_Z 7. SURLAG 8. CANMX 9. SHALLST Parameters 10. REVAPMN 11. RCHRG_DP 12. ESCO 13. EPCO 14. LAT_TIME 15. EVRCH 16. GW_REVAP 17. PLAPS 18. HRU_SLP 19. OV_N 20. SLSUBBSN 21. CH_K1 22. CH_K2 23. CH_N1 24. CH_N2 25. SLSOIL
Baseline Flow Calibration C.R. Objective function (maximize): Nash-Sutcliffe (1970) STATISTIC SUMMARY Variable FLOW_OUT_1 p-factor 1.00 r-factor 0.38 R2 0.99 NS 0.99 br2 0.9642 MSE 0.011 SSQR 0.0032 PBIAS -2.5 KGE 0.96 RSR 0.11 MNS 0.95 VOL_FR 0.98 Parameter_Name Fitted_Value Min_value Max_value 1:V GW_REVAP.gw 0.024050 0.015 0.025 2:V ESCO.hru 0.956500 0.9 1 3:R SOL_AWC(..).sol 0.041500-0.05 0.05 4:R CN2.mgt -0.016675-0.1 0.065 5:R REVAPMN.gw -0.024800-0.08 0.08 6:R ALPHA_BF.gw -0.013800-0.06 0.06 7:R SOL_Z(..).sol -0.076000-0.4 0.4 Type of change: v_ value replaced by a given value r_ means an existing value is multiplied by (1+ a given value)
Flow Validation C.R. Variable STATISTIC SUMMARY FLOW_OUT_1 p-factor 0.86 r-factor 0.40 R2 0.96 NS 0.95 br2 0.941 MSE 0.035 SSQR 0.0028 PBIAS -4.1 KGE 0.95 RSR 0.21 MNS 0.85 VOL_FR 0.96
250 200 [mm/month] 150 100 50 0 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sept Rain [mm/month] PET [mm/month] ET [mm/month] 14 12 12.55 11.83 [mm/month] 10 8 6 4 2 0 9.34 9.63 9.15 8.36 8.03 7.22 6.76 5.6 5.81 4.9 4.4 4.60 3.95 4.11 3.72 3.21 3.25 2.46 2.71 1.9 2.18 1.95 2.19 1.6 1.59 1.4 0.90 1.19 1.49 0.32 0.42 0.29 0.32 0.27 0.32 0.32 0.4 0.3 0.6 0.76 0.03 0.12 0.09 0.27 0.1 0.01 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sept Lat Q [mm/month] Surf Q [mm/month] Gw Flow [mm/month] Water Yield [mm/month]
Scenario Analysis C.R. results (with calibration parameter value transfer) Scenario Water Balance variation C.R. with respect to Baseline 2% 1.5% 1.7% 1% 0% 0.3% 0.0% 0.7% 0.8% -1% -0.3% -0.2% -0.5% -0.6% -2% -3% -4% -3.5% LSH LBA LSP -3.0% Evapotranspiration[mm/yr] Flow Out [mm/yr] Soil Storage [mm/yr] DA recharge [mm/yr] Scenario Precipitation [mm/yr] Evapotranspiration [mm/yr] Flow Out [mm/yr] Soil Storage [mm/yr] DA recharge [mm/yr] Baseline 435.6 341.2 70.39 20.4 3.61 LSH 435.6 340.1 71.48 20.35 3.67 LBA 435.6 342.3 70.03 19.68 3.59 LSP 435.6 341.3 70.87 19.79 3.64
Water Provision Results Scenario Precipitation Evapotranspiration Total Flow Out Soil Storage Irrigation* DA recharge [hm 3 /yr] [hm 3 /yr] [hm 3 /yr] [hm 3 /yr] [hm 3 /yr] [hm 3 /yr] Baseline 105.68 82.87 16.88 5.06 0.97 0.87 LSH 105.68 82.60 17.14 5.05 0.97 0.88 LBA 105.68 83.11 16.76 4.94 1.09 0.86 LSP 105.68 82.87 16.98 4.95 1.07 0.87 * Irrigation volume is included in Evapotranspiration volume. Table. 2. System Water Flows with SWAT model. 15% 10% LSH LBA LSP 12.3% 9.4% 5% 0% -5% -0.3% 1.5% -0.1% 1.7% -0.9% 0.3% 0.0% 0.6% -0.7% -0.6% -2.4% -2.1% 0.6% Evapotranspiration [m3/yr] Flow Out [m3/yr] Soil Storage [m3/yr] DA recharge [m3/yr] Irrigation [m3/yr] Fig. 4. Scenario Water Balance variation with respect to Baseline. Scenario Evapotranspiration Total Flow Out Soil Storage DA recharge Total variation [hm 3 /yr] [hm 3 /yr] [hm 3 /yr] [hm 3 /yr] [hm 3 /yr] LSH + 0.27 + 0.26-0.10-0.10 + 0.53 LBA - 0.24-0.12-0.12-0.01-0.49 LSP 0.00-0.10-0.11 0.00-0.21 21 Table. 3. Total Volume Water Balance variation with respect to Baseline.
10 Years Water Provision Results Scenario Precipitation Evapotranspiration Total Flow Out Soil Storage & DA recharge [mm]/[hm 3 ] [mm]/[hm 3 ] [mm]/[hm 3 ] SA[mm]/[hm 3 ] [mm]/[hm 3 ] Baseline 4343 / 1054 3166,09 / 768,09 663,29 / 160,91 480,15 / 116,88 33,47 / 8,12 LSH 4343 / 1054 3175,61 / 770,40 656,16 / 159,18 478.29 / 116,43 32,94 / 7,99 LBA 4343 / 1054 3174,85 / 770.22 653,39 / 158,51 481,94 / 117,31 32,82 / 7,96 LSP 4343 / 1054 3175,47 / 770,36 655, 86 / 159,11 544,62 / 116,54 32,95 / 7,99 0.50% 0.00% -0.50% -1.00% -1.50% -2.00% -2.50% 0.30% LSH LBA LSP 0.28% 0.37% 0.30% -0.39% -0.29% -1.08% -1.12% -1.60% -1.49% -1.97% Evapotranspiration Total Flow Out Soil Storage & SA DA recharge -1.60% hm3 3 2 1 0-1 -2-3 LSH LBA LSP 2.31 2.13 2.27-1.73-0.45-2.40 0.43-0.13-0.16-0.34-0.13 Evapotranspiration [hm3] Total Flow Out [hm3] Soil Storage & SA[hm3] DA recharge [hm3] -1.80 22
Q95 Q90 DRBA limit Low Flow Baseline: Q95 (percentil 5) and Q90 (percentil 10) Volume[hm3] 1.40 1.20 1.00 0.80 0.60 0.40 0.20 0.00 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sept Q95 Q90 DRBA limit LSP: Q95 (percentil 5) and Q90 (percentil 10) Volume[hm3] 1.40 1.20 1.00 0.80 0.60 0.40 0.20 0.00 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sept
Low Flow LBA: Q95 (percentil 5) and Q90 (percentil 10) Volume[hm3] 1.40 1.20 1.00 0.80 0.60 0.40 0.20 0.00 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sept Q95 Q90 DRBA limit LSH: Q95 (percentil 5) and Q90 (percentil 10) Volume[hm3] 1.40 1.20 1.00 0.80 0.60 0.40 0.20 0.00 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sept Q95 Q90 DRBA limit
Low Flow Q95 (percentil 5) 6.0% 4.0% 2.0% 0.0% -2.0% -4.0% -6.0% -8.0% Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sept Q95_LSH Q95_ LBA Q95_LSP Q90 (percentil 10) 6.0% 4.0% 2.0% 0.0% -2.0% -4.0% -6.0% -8.0% -10.0% -12.0% Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sept Q90_LSH Q90_ LBA Q90_LSP
Economic Analysis 50% 40% 30% 20% 10% 0% -10% -20% -30% Warm-Up Agricultural economy variation with respect to Baseline (C.R.) DRY NORMAL WET WET DRY WET DRY DRY WET NORMAL 2003-2004 2004-2005 2005-2006 2006-2007 2007-2008 2008-2009 2009-2010 2010-2011 2011-2012 2012-2013 2013-2014 LSH LBA LSP 25% 20% 15% 10% 5% Total Variation in 10 years (2004-2014) (C.R.) 4.15% 19.43% Scenario TOTAL_SCENARIO (2004-2014) Baseline 110 944 624 LSH 107 125 983 LBA 115 551 296 LSP 132 499 658 0% -5% -3.44% LSH LBA LSP
Conclusions C.R. setup in SWAT its important to obtain more realistic models. C.R. scenarios could provide further insights to optimize land use change and rotational crop patterns in a more sustainable way. Water balance components in sub-arid areas are sensitive to C.R. due of low flow during spring-summer periods. Irrigation schemas have to be reformulated in this subbasin facing to CC and to achieve a good ecological status. Fallow land use its important in subarid watersheds
Thanks! Ana Tarquis Bárbara Willaarts Angel de Miguel David Rivas